Sample records for postulated core melt

  1. Containment response to postulated core meltdown accidents in the fast flux test facility

    Microsoft Academic Search

    R. D. Gasser; W. T. Pratt

    1980-01-01

    An assessment is made of the containment margin available in the Fast Flux Test Facility to mitigate the consequences of a postulated failure of in-vessel post-accident heat removal following a hypothetical core disruptive accident. The consequences of a number of assumed meltdown configurations (both in-vessel and ex-vessel) are assessed using the CACECO (CAvty, CEll, COntainment) containment analysis computer code together

  2. The Annular Core Research Reactor (ACRR) postulated limiting event initial and building source terms

    SciTech Connect

    Restrepo, L F

    1992-08-01

    As part of the update of the Safety analysis Report (SAR) for the Annular Core Research Reactor (ACRR), operational limiting events under the category of inadvertent withdrawal of an experiment while at power or during a power pulse were determined to be the most limiting event(s) for this reactor. This report provides a summary of the assumptions, modeling, and results in evaluation of: Reactivity and thermal hydraulics analysis to determine the amount of fuel melt or fuel damage ratios; The reactor inventories following the limiting event; A literature review of post NUREG-0772 release fraction experiment results on severe fuel damages; Decontamination factors due to in-pool transport; and In-building transport modeling and building source term analysis.

  3. Melting of subducted basalt at the core-mantle boundary.

    PubMed

    Andrault, Denis; Pesce, Giacomo; Bouhifd, Mohamed Ali; Bolfan-Casanova, Nathalie; Hénot, Jean-Marc; Mezouar, Mohamed

    2014-05-23

    The geological materials in Earth's lowermost mantle control the characteristics and interpretation of seismic ultra-low velocity zones at the base of the core-mantle boundary. Partial melting of the bulk lower mantle is often advocated as the cause, but this does not explain the nonubiquitous character of these regional seismic features. We explored the melting properties of mid-oceanic ridge basalt (MORB), which can reach the lowermost mantle after subduction of oceanic crust. At a pressure representative of the core-mantle boundary (135 gigapascals), the onset of melting occurs at ~3800 kelvin, which is ~350 kelvin below the mantle solidus. The SiO2-rich liquid generated either remains trapped in the MORB material or solidifies after reacting with the surrounding MgO-rich mantle, remixing subducted MORB with the lowermost mantle. PMID:24855266

  4. Inner Core Melting and Freezing: Where and How (Invited)

    NASA Astrophysics Data System (ADS)

    Cormier, V. F.

    2010-12-01

    Combined sesimology, geodynamic, and geodynamo modeling can test several hypotheses for the mechanisms of growth of Earth’s inner core exhibited by hemispherical lateral variations in its upper 600 km. Weak backscattered PKiKP in the equatorial eastern hemisphere can be made consistent with either a hypothesis of freezing or melting. In a melting hypothesis, the eastern hemisphere is older with possibly larger crystals or smaller elastic contrasts across grain boundaries providing weaker backscatter to the coda of PKiKP. By viscolasticity, partial melt or high homologous temperatures might then explain the lower Q of transmitted PKIKP in the eastern hemisphere. Alternatively, an eastern hemisphere that grows radially outward might have crystals stretched in the vertical direction. By scattering, this hypothesis can simultaneously explain weak backscattered PKiKP coda and high attenuation of transmitted PKIKP from the loss of backscattered energy at angles perpendicular to the vertically oriented crystals. Pseudospectral synthesis that combines texture and viscoelasticity can help discriminate between these two mechanisms. Geodynamic and geodynamo modeling can assist in this discrimination: (1) by predicting flow patterns in outer core, including their influence on spatial spectrum of the non-dipole field and the stability of a layer of reduced gradient in compressional velocity near the inner core boundary; (2) by predicting the deformation in the uppermost solid inner core, including its effect on elastic and attenuation anisotropy.

  5. Dissipative melting as a mechanism for core formation

    NASA Astrophysics Data System (ADS)

    Turcotte, D. L.; Emerman, S. H.

    1983-11-01

    Cosmochemical studies strongly favor a near-homogeneous accretion of the earth. These studies also show that core segregation probably occurred within the first 100,000 years of earth history. Mechanisms of core formation have received relatively little attention. The principal purpose of this paper is to examine dissipative melting as a possible mechanism for core segregation. For a large iron body migrating through the mantle, the potential energy lost by the body is dissipated by frictional heating. If the body has a radius greater than about 30 km, the frictional heating is sufficient to melt a path through which the body can fall. If the iron body is liquid (as expected) with a low viscosity, it would penetrate the mantle as a diapir. The problem of an immiscible liquid body melting its way through a solid is solved, and a family of diapir shapes is obtained. It is found that dissipative heating may be a viable mechanism for core segregation if sufficiently large bodies of liquid iron can form.

  6. Melting curves and entropy of melting of iron under Earth's core conditions

    NASA Astrophysics Data System (ADS)

    Zhang, Wen-Jin; Liu, Zhi-Yong; Liu, Zhong-Li; Cai, Ling-Cang

    2015-07-01

    The melting curves of iron are determined up to 365 GPa via molecular dynamic (MD) simulations combining with the embedded atom model (EAM) potential developed by Ackland et al. We simulated the melting with three approaches, the hysteresis, two-phase and recently modified Z methods. All three techniques can produce satisfying results, consistent well with most of static compression measurements and shock experiments. Hence, we recommend that these three techniques and this EAM potential are reliable techniques and potential for simulating melting properties of iron. Fitting the well-known Simon equation to our two-phase data we yield the analytical melting curve for iron: 1825(1 + P/57.723)0.654, which gives a melting point at the inner core boundary of 6345 K, very close to the recent diamond anvil cell (DAC) extrapolated value and other ab initio calculations. Furthermore, the analyses of our entropy of melting and solid-liquid interfacial energy ?sl indicate that at high pressure, the entropy of fusion shows weak pressure effect. The ?sl increases monotonically with pressure, and can be described as a second-order polynomial relation.

  7. Reevaluation of the reconstruction of summer temperatures from melt features in Belukha ice cores, Siberian Altai

    Microsoft Academic Search

    Sachiko Okamoto; Koji Fujita; Hideki Narita; Jun Uetake; Nozomu Takeuchi; Takayuki Miyake; Fumio Nakazawa; Vladimir B. Aizen; Stanislav A. Nikitin; Masayoshi Nakawo

    2011-01-01

    In a previous study, past summer temperatures were reconstructed from melt features in the Belukha ice core, Siberian Altai. We evaluated the climatic representativeness of net accumulation and melt features by comparing two Belukha ice cores retrieved at neighboring sites by different institutions and dated by different methods. Melt features in both cores showed a significant correlation, but the trends

  8. The adiabatic gradient and the melting point gradient in the core of the earth

    Microsoft Academic Search

    G. Higgins; G. C. Kennedy

    1971-01-01

    The melting gradient and the adiabatic gradient throughout the core of the earth are compared. The temperature of melting of iron at pressures equivalent to the inner core-outer core boundary is estimated to be circa 4250øC with a melting point gradient of approximately 500 ø through the outer core. The adiabatic gradient through the outer core is estimated to be

  9. Termination of light-water reactor core-melt accidents with a chemical core catcher: the core-melt source reduction system (COMSORS)

    SciTech Connect

    Forsberg, C.W.; Parker, G.W.; Rudolph, J.C.; Osborne-Lee, I.W. [Oak Ridge National Lab., TN (United States); Kenton, M.A. [Dames and Moore, Westmont, IL (United States)

    1996-09-01

    The Core-Melt Source Reduction System (COMSORS) is a new approach to terminate light-water reactor core melt accidents and ensure containment integrity. A special dissolution glass is placed under the reactor vessel. If core debris is released onto the glass, the glass melts and the debris dissolves into the molten glass, thus creating a homogeneous molten glass. The molten glass, with dissolved core debris, spreads into a wide pool, distributing the heat for removal by radiation to the reactor cavity above or by transfer to water on top of the molten glass. Expected equilibrium glass temperatures are approximately 600 degrees C. The creation of a low-temperature, homogeneous molten glass with known geometry permits cooling of the glass without threatening containment integrity. This report describes the technology, initial experiments to measure key glass properties, and modeling of COMSORS operations.

  10. Seismic velocity decrement ratios for regions of partial melt near the core-mantle boundary

    Microsoft Academic Search

    James G. Berryman

    1999-01-01

    For regions of partial melt in the lower mantle, both compressional and shear wave ve- locities decrease monotonically with increasing melt volume fraction. It has been ob- served that regions close to the core-mantle boundary thought to contain partial melt have a velocity decrement ratio (relative change in shear velocity over relative change of com- pressional velocity) of about 3.

  11. Reevaluation of past summer temperature reconstruction by melt features in Belukha ice cores, Russian Altai

    Microsoft Academic Search

    S. Okamoto; K. Fujita; H. Narita; J. Uetake; N. Takeuchi; T. Miyake; F. Nakazawa; V. Aizen; S. Nikitin; M. Nakawo

    2009-01-01

    Past summer temperature has been reconstructed by melt features in Belukha ice core in a previous study. We evaluated a climatic representativeness of isotope, net accumulation and melt feature by comparing two Belukha ice cores retrieved by different institutions and dated by different methods. We find a significant correlation between seasonal changes in stable isotope in precipitation and air temperature.

  12. Examination of offsite radiological emergency measures for nuclear reactor accidents involving core melt. [PWR

    Microsoft Academic Search

    D. C. Aldrich; P. E. McGrath; N. C. Rasmussen

    1978-01-01

    Evacuation, sheltering followed by population relocation, and iodine prophylaxis are evaluated as offsite public protective measures in response to nuclear reactor accidents involving core-melt. Evaluations were conducted using a modified version of the Reactor Safety Study consequence model. Models representing each measure were developed and are discussed. Potential PWR core-melt radioactive material releases are separated into two categories, ''Melt-through'' and

  13. Temperatures in Earth's Core Based on Melting and Phase Transformation Experiments on Iron

    Microsoft Academic Search

    S. K. Saxena; G. Shen; P. Lazor

    1994-01-01

    Experiments on melting and phase transformations on iron in a laser-heated, diamondanvil cell to a pressure of 150 gigapascals (approximately 1.5 million atmospheres) show that iron melts at the central core pressure of 363.85 gigapascals at 6350 ± 350 kelvin. The central core temperature corresponding to the upper temperature of iron melting is 6150 kelvin. The pressure dependence of iron

  14. Ex-Vessel Core Melt Modeling Comparison between MELTSPREAD-CORQUENCH and MELCOR 2.1

    SciTech Connect

    Robb, Kevin R [ORNL; Farmer, Mitchell [Argonne National Laboratory (ANL); Francis, Matthew W [ORNL

    2014-03-01

    System-level code analyses by both United States and international researchers predict major core melting, bottom head failure, and corium-concrete interaction for Fukushima Daiichi Unit 1 (1F1). Although system codes such as MELCOR and MAAP are capable of capturing a wide range of accident phenomena, they currently do not contain detailed models for evaluating some ex-vessel core melt behavior. However, specialized codes containing more detailed modeling are available for melt spreading such as MELTSPREAD as well as long-term molten corium-concrete interaction (MCCI) and debris coolability such as CORQUENCH. In a preceding study, Enhanced Ex-Vessel Analysis for Fukushima Daiichi Unit 1: Melt Spreading and Core-Concrete Interaction Analyses with MELTSPREAD and CORQUENCH, the MELTSPREAD-CORQUENCH codes predicted the 1F1 core melt readily cooled in contrast to predictions by MELCOR. The user community has taken notice and is in the process of updating their systems codes; specifically MAAP and MELCOR, to improve and reduce conservatism in their ex-vessel core melt models. This report investigates why the MELCOR v2.1 code, compared to the MELTSPREAD and CORQUENCH 3.03 codes, yield differing predictions of ex-vessel melt progression. To accomplish this, the differences in the treatment of the ex-vessel melt with respect to melt spreading and long-term coolability are examined. The differences in modeling approaches are summarized, and a comparison of example code predictions is provided.

  15. Temperatures in the earth's core from melting-point measurements of iron at high static pressures

    Microsoft Academic Search

    R. Boehler

    1993-01-01

    The most reliable method for determining the temperature gradient at the earth's core is the estimation of Fe and Fe-rich compounds' melting temperature at the pressure of the inner core boundary. Attention is presently given to melting-point measurements on Fe and Fe-O compounds at up to 2 Mbar. An extrapolation of these results to 3.3 Mbar yields an inner core

  16. Melting induced stratification above the Earth's inner core due to convective translation

    E-print Network

    Boyer, Edmond

    Melting induced stratification above the Earth's inner core due to convective translation Thierry but that the observed seismic velocities can be explained by a stratification in light elements (and temperature). However, the stratification mechanism by crystallization and melting of crystals at different depths

  17. Examination of offsite radiological emergency protective measures for nuclear reactor accidents involving core melt

    E-print Network

    Aldrich, David C.

    1979-01-01

    Evacuation, sheltering followed by population relocation, and iodine prophylaxis are evaluated as offsite public protective measures in response to nuclear reactor accidents involving core-melt. Evaluations were conducted ...

  18. Convection at the melting point: A thermal history of the earth's core

    Microsoft Academic Search

    Willem V. R. Malkus

    1972-01-01

    Higgins and Kennedy (1971) concluded that the Earth's fluid core has a stable stratification if it is at its melting point. Busse (1972) and Elsasser suggested as an alternative that a hydrostatic-isentropic distribution of particulate solid can produce neutral stability in a partially molten core. Here this suggestion is quantified and a determination is made of the efficiency of the

  19. Shock temperatures and melting of iron at Earth core conditions

    Microsoft Academic Search

    C. S. Yoo; N. C. Holmes; M. Ross; D. J. Webb; C. Pike

    1993-01-01

    The temperature of shock compressed iron has been measured to 340 GPa, using well characterized iron films sputtered on transparent diamond substrates and a 1 ns time-resolved optical method. We find a knee on the ([ital P],[ital T]) iron Hugoniot indicating melting at 6350 K and 235 GPa and at 6720 K and 300 GPa. An extrapolation yields an iron

  20. Crystallization of ion clouds in octupole traps: Structural transitions, core melting, and scaling laws

    SciTech Connect

    Calvo, F.; Champenois, C.; Yurtsever, E. [LASIM, Universite Claude Bernard Lyon 1 and CNRS, UMR 5579, 43 Boulevard du 11 Novembre 1918, F69622 Villeurbanne Cedex (France); PIIM, UMR 6633, Universite de Provence and CNRS, Campus Universitaire de Saint-Jerome C21, F13397 Marseille Cedex 20 (France); Koc University, Rumelifeneriyolu, Sariyer, Istanbul 34450 (Turkey)

    2009-12-15

    The stable structures and melting properties of ion clouds in isotropic octupole traps are investigated using a combination of semianalytical and numerical models, with a particular emphasis at finite-size scaling effects. Small-size clouds are found to be hollow and arranged in shells corresponding approximately to the solutions of the Thomson problem. The shell structure is lost in clusters containing more than a few thousands of ions, the inner parts of the cloud becoming soft and amorphous. While melting is triggered in the core shells, the melting temperature follows the rule expected for three-dimensional dense particles, with a depression scaling linearly with the inverse radius.

  1. Chemical Convention in the Lunar Core from Melting Experiments on the Ironsulfur System

    SciTech Connect

    Li, J.; Liu, J.; Chen, B.; Li, Z.; Wang, Y. (Michigan); (UC)

    2012-03-26

    By reanalyzing Apollo lunar seismograms using array-processing methods, a recent study suggests that the Moon has a solid inner core and a fluid outer core, much like the Earth. The volume fraction of the lunar inner core is 38%, compared with 4% for the Earth. The pressure at the Moon's core-mantle boundary is 4.8 GPa, and that at the ICB is 5.2 GPa. The partially molten state of the lunar core provides constraints on the thermal and chemical states of the Moon: The temperature at the inner core boundary (ICB) corresponds to the liquidus of the outer core composition, and the mass fraction of the solid core allows us to infer the bulk composition of the core from an estimated thermal profile. Moreover, knowledge on the extent of core solidification can be used to evaluate the role of chemical convection in the origin of early lunar core dynamo. Sulfur is considered an antifreeze component in the lunar core. Here we investigate the melting behavior of the Fe-S system at the pressure conditions of the lunar core, using the multi-anvil apparatus and synchrotron and laboratory-based analytical methods. Our goal is to understand compositionally driven convection in the lunar core and assess its role in generating an internal magnetic field in the early history of the Moon.

  2. Melt spreading code assessment, modifications, and application to the EPR core catcher design.

    SciTech Connect

    Farmer, M. T .; Nuclear Engineering Division

    2009-03-30

    The Evolutionary Power Reactor (EPR) is under consideration by various utilities in the United States to provide base load electrical production, and as a result the design is undergoing a certification review by the U.S. Nuclear Regulatory Commission (NRC). The severe accident design philosophy for this reactor is based upon the fact that the projected power rating results in a narrow margin for in-vessel melt retention by external cooling of the reactor vessel. As a result, the design addresses ex-vessel core melt stabilization using a mitigation strategy that includes: (1) an external core melt retention system to temporarily hold core melt released from the vessel; (2) a layer of 'sacrificial' material that is admixed with the melt while in the core melt retention system; (3) a melt plug in the lower part of the retention system that, when failed, provides a pathway for the mixture to spread to a large core spreading chamber; and finally, (4) cooling and stabilization of the spread melt by controlled top and bottom flooding. The overall concept is illustrated in Figure 1.1. The melt spreading process relies heavily on inertial flow of a low-viscosity admixed melt to a segmented spreading chamber, and assumes that the melt mass will be distributed to a uniform height in the chamber. The spreading phenomenon thus needs to be modeled properly in order to adequately assess the EPR design. The MELTSPREAD code, developed at Argonne National Laboratory, can model segmented, and both uniform and nonuniform spreading. The NRC is thus utilizing MELTSPREAD to evaluate melt spreading in the EPR design. MELTSPREAD was originally developed to support resolution of the Mark I containment shell vulnerability issue. Following closure of this issue, development of MELTSPREAD ceased in the early 1990's, at which time the melt spreading database upon which the code had been validated was rather limited. In particular, the database that was utilized for initial validation consisted of: (1) comparison to an analytical solution for the dam break problem, (2) water spreading tests in a 1/10 linear scale model of the Mark I containment by Theofanous et al., and (3) steel spreading tests by Suzuki et al. that were also conducted in a geometry similar to the Mark I. The objective of this work was to utilize the MELTSPREAD code to check the assumption of uniform melt spreading in the EPR core catcher design. As a starting point for the project, the code was validated against the worldwide melt spreading database that emerged after the code was originally written in the very early 1990's. As part of this exercise, the code was extensively modified and upgraded to incorporate findings from these various analytical and experiment programs. In terms of expanding the ability of the code to analyze various melt simulant experiments, the options to input user-specified melt and/or substrate material properties was added. The ability to perform invisicid and/or adiabatic spreading analysis was also added so that comparisons with analytical solutions and isothermal spreading tests could be carried out. In terms of refining the capability to carry out reactor material melt spreading analyses, the code was upgraded with a new melt viscosity model; the capability was added to treat situations in which solid fraction buildup between the liquidus-solidus is non-linear; and finally, the ability to treat an interfacial heat transfer resistance between the melt and substrate was incorporated. This last set of changes substantially improved the predictive capability of the code in terms of addressing reactor material melt spreading tests. Aside from improvements and upgrades, a method was developed to fit the model to the various melt spreading tests in a manner that allowed uncertainties in the model predictions to be statistically characterized. With these results, a sensitivity study was performed to investigate the assumption of uniform spreading in the EPR core catcher that addressed parametric variations in: (1) melt pour mass, (2) melt composition, (3) me

  3. Svalbard summer melting, continentality, and sea ice extent from the Lomonosovfonna ice core

    Microsoft Academic Search

    Aslak Grinsted; John C. Moore; Veijo Pohjola; Tõnu Martma; Elisabeth Isaksson

    2006-01-01

    We develop a continentality proxy (1600-1930) based on amplitudes of the annual signal in oxygen isotopes in an ice core. We show via modeling that by using 5 and 15 year average amplitudes the effects of diffusion and varying layer thickness can be minimized, such that amplitudes then reflect real seasonal changes in delta18O under the influence of melt. A

  4. Svalbard summer melting, continentality, and sea ice extent from the Lomonosovfonna ice core

    Microsoft Academic Search

    Aslak Grinsted; John C. Moore; Veijo Pohjola; Tõnu Martma; Elisabeth Isaksson

    2006-01-01

    We develop a continentality proxy (1600–1930) based on amplitudes of the annual signal in oxygen isotopes in an ice core. We show via modeling that by using 5 and 15 year average amplitudes the effects of diffusion and varying layer thickness can be minimized, such that amplitudes then reflect real seasonal changes in ?18O under the influence of melt. A

  5. Possible reasons of shock melt deficiency in the Bosumtwi drill cores

    Microsoft Academic Search

    N. Artemieva

    2007-01-01

    Pre-drilling numerical modeling of the Bosumtwi impact event predicted a 200 m thick coherent melt layer, as well as abundant highly shocked target material within the central part of the crater structure. However, these predictions are in disagreement with data from drill core obtained in 2004-2005. Here I provide a brief overview of previous results and discuss possible reasons behind

  6. Near-Melting Condition of the Inner Core Boundary Revealed from Antipodal Seismic Waves

    NASA Astrophysics Data System (ADS)

    Cormier, V. F.; Attanayake, J.; de Silva, S. M. S.; Miller, M. S.; Thomas, C.

    2014-12-01

    First-principles calculations1 have suggested that the inner core's low shear velocity (3.5 km/sec) is a consequence of its temperature being very close to its melting temperature throughout its volume. Near the inner core's freezing or melting boundary, the shear modulus could possibly approach zero. A test of this is made from observations of the amplitude of PKIIKP waves at antipodal (>175o) ranges. These underside reflections are very sensitive to the S velocity beneath the inner core boundary due to energy subtracted from PKIIKP by converted S energy. This sensitivity is exploited by modeling PKIIKP waveforms observed by a transportable array in Morocco, which recorded many high-quality antipodal waveforms from Tonga. Differences in the in the sampling of the upper inner core between PKIIKP arriving from the short (<180o) and long (>180o) distances make it feasible to investigate lateral differences in the elastic and anelastic states of uppermost inner core from the amplitude and frequency content of the waveforms. In computational experiments, we show that a zero or small shear modulus in the uppermost inner core is the most effective way of matching large amplitude PKIIKP's observed from antipodal paths from Tonga to Morocco. The correlation of this bright spot in the PKIIKP reflection with a thin zone of low P velocity identified from multi-pathed PKIKP waves sampling a portion of the equatorial eastern hemisphere2suggests that at least this region of the inner core is near its melting temperature. Waveform modeling of PKIKP and PKIIKP from the combined effects of viscoelasticity and forward scattering is performed to determine whether this region of low shear modulus is consistent with freezing or melting. 1Martorell, B., L. Vocadlo, J.P. Brodholt, and I.G.Wood, (2013) Science, 342 (6157), doi: 10.1126/science.1243651. 2Stroujkova, A., and V.F. Cormier (2004), J. Geophys. Res., 109(B10), doi:10.1029/2004JB002976.

  7. Effect of Hydrogen and Carbon on the Melting Temperature of the Core

    NASA Astrophysics Data System (ADS)

    Nakajima, Y.; Sakamaki, K.; Takahashi, E.; Fukai, Y.; Suzuki, T.; Funakoshi, K.

    2007-12-01

    The temperature of the Earth's outer core has been discussed based on the melting temperature of Fe- O-S alloys (e.g., Boehler, 1996). Although hydrogen and carbon are the possible candidates of the core component, their effects on the melting temperature of iron at high-pressures are unclear. Using a Kawai-type multi-anvil apparatus at SPring-8 synchrotron, we carried out a series of melting experiments on FeH and Fe3C up to 20 and 28 GPa, respectively. In the experiments on FeH, Fe sponge mixed with MgO was packed into a NaCl container with a hydrogen source, LiAlH4 (e.g., Fukai et al., 1989). During heating under high-pressures, hydrogenation of iron was observed by volume change. The phase boundary between ?'-phase (low-temperature phase) and ?-phase (high-temperature phase) of iron-hydride was determined using both cooling and heating experiments. Hydrogen concentrations in the ?-FeHx and ?'-FeHx were calculated based on the excess volume data from that of pure iron. It is found that ?-FeHx and ?'-FeHx synthesized in our experiments at pressures between 10 and 20 GPa are nearly stoichiometric FeH. Melting temperature of the ?-FeH was determined by the abrupt change in the X-ray diffraction patterns (crystalline to amorphous). The melting temperatures were determined to be 1473, 1473, 1493, 1573 and 1593 K at 10, 11.5, 15, 18 and 20 GPa, respectively. In the experiments using Fe3C, the synthesized Fe3C powder was encapsulated in a MgO container. In the diffraction sequences during heating, the peaks of Fe3C disappeared, and the new peaks identified as those of Fe7C3 were observed with halo caused by liquid. Finally, the Fe7C3 peaks disappeared, and only the halo pattern was observed. Based on these observations, the incongruent melting of Fe3C to Fe7C3 and liquid is estimated to occur at 1823 and 1923 K at 19.7 and 27.0 GPa, respectively. The liquidus temperatures of the Fe3C composition are found to be at 2098 and 2198 K at 19.5 and 26.8 GPa, respectively. The melting temperatures of Fe3C determined by our experiments are >700 K lower than that of the previous estimation based on thermodynamic calculation (Wood, 1993). Our experimental results show a possibility that the hydrogen and carbon lower the melting temperature of iron (outer core) dramatically. The melting temperatures of ?-FeH and Fe3C at 20 GPa are already 500 K lower than that of pure iron estimated by Anderson and Isaak (2000). Extrapolating our experimental melting curves for FeH and Fe3C to core pressures using Lindemann's melting law, we obtained the melting temperatures to be ~2600 and ~2900 K at the core-mantle boundary (CMB), respectively. In the presence of both hydrogen and carbon, melting temperature of the Earth's outer core could be >1500 K lower than that of the previous estimates, implying that the temperature gap at CMB could be much smaller than the current estimates.

  8. Silicate melt inclusions and glasses in lunar soil fragments from the Luna 16 core sample

    USGS Publications Warehouse

    Roedder, E.; Weiblen, P.W.

    1972-01-01

    More than 2000 fragments were studied microscopically, and electron microprobe analyses were made of 39 selected areas, from a few square mm of polished surface, through 75- to 425-??m fragments of lunar soil from two samples of the Luna 16 core. The silicate melt inclusions and glasses differ in important details from those observed earlier in the Apollo samples. Melt inclusions in olivine contain epitaxially oriented daughter crystals, but also show a similar epitaxy around the outside of the crystals not observed in previous lunar samples. Melt inclusions in ilmenite suggest trapping at successive stages in a differentiation sequence. There is abundant evidence for late-stage silicate liquid immiscibility, with melt compositions similar but not identical to those from Apollo 11 and 12. A comparison of the alkali ratio of any given bulk rock analysis with that of its late-stage, high-silica melt shows gross differences for different rocks. This is pertinent to understanding late-stage differentiation processes. Glass fragments and spherules exhibit a wide range of crystallization textures, reflecting their wide range of compositions and cooling histories. No significant differences were found between the two portions of core examined (Zones A and D). ?? 1972.

  9. Properties of liquid iron along the melting line up to Earth-core pressures.

    PubMed

    Fomin, Yu D; Ryzhov, V N; Brazhkin, V V

    2013-07-17

    We report a molecular dynamics study of the transport coefficients and the infinite frequency shear modulus of liquid iron at high temperatures and high pressures. We observe a simultaneous rise of both the shear viscosity and the diffusion coefficient along the melting line and estimate whether liquid iron can vitrify under Earth-core conditions. We show that in the conditions of the model studied in our work iron demonstrates a moderate increase of viscosity along the melting line. It is also demonstrated that at the limit of high temperatures and high pressures the liquid iron behaves similarly to the soft sphere system with exponent n ? 4.6. PMID:23756492

  10. The melting curve of Ni to 125 GPa: implications for Earth's Fe rich core alloy

    NASA Astrophysics Data System (ADS)

    Lord, O. T.; Wood, I. G.; Dobson, D. P.; Vocadlo, L.; Thomson, A. R.; Wann, E.; Wang, W.; Edgington, A.; Morard, G.; Mezouar, N.; Walter, M. J.

    2014-12-01

    The melting curve of Ni has been determined to 125 GPa using laser-heated diamond anvil cell (LH-DAC) experiments and two melting criteria: the appearance of liquid diffuse scattering (LDS) during in situ X-ray diffraction (XRD) and simultaneous plateaux in temperature vs. laser power functions [1]. Our melting curve (Fig. 1) is in good agreement with most theoretical studies [e.g. 2] and the available shock wave data (Fig. 2). It is, however, dramatically steeper than the previous off-line LH-DAC studies in which the determination of melting was based on the visual observation of motion aided by the laser speckle method [e.g. 3]. We estimate the melting point of Ni at the inner-core boundary (ICB; 330 GPa) to be 5800±700 K (2?), ~2500 K higher than the estimate based on the laser speckle method [3] and within error of Fe (6230±500 K) as determined in a similar in situ LH-DAC study [4]. We find that laser speckle based melting curves coincide with the onset of rapid sub-solidus recrystallization, suggesting that visual observations of motion may have misinterpreted dynamic recrystallization as melt convection. Our new melting curve suggests that the reduction in ICB temperature due to the alloying of Ni with Fe is likely to be significantly smaller than would be expected had the earlier experimental Ni melting studies been correct. We have applied our methodology to a range of other transition metals (Mo, Ti, V, Cu). In the case of Mo, Ti and V the melting curves are in good agreement with the shock compression and theoretical melting studies but hotter and steeper than those based on the laser speckle method, as with Ni. Cu is an exception in which all studies agree, including those employing the laser speckle method. These results go a long way toward resolving the the long-standing controversy over the phase diagrams of the transition metals as determined from static LH-DAC studies on the one hand, and theoretical and dynamic compression studies on the other. [1] Lord et al. (2014) Phys Earth Planet Inter [2] Pozzo M, Alfè D (2013) Phys Rev B, 88:024111 [3] Errandonea et al. (2001) Phys Rev B, 63:132104 [4] Anzellini et al. (2013) Science, 340:464-466

  11. The structure of melting mushy zones, with implications for Earth's inner core (Invited)

    NASA Astrophysics Data System (ADS)

    Bergman, M. I.; Huguet, L.; Alboussiere, T.

    2013-12-01

    Seismologists have inferred hemispherical differences in the isotropic wavespeed, the elastic anisotropy, the attenuation, and the attenuation anisotropy of Earth's inner core. One hypothesis for these hemispherical differences involves an east-west translation of the inner core, with enhanced solidification on one side and melting on the other. Another hypothesis is that long term mantle control over outer core convection can lead to hemispherical variations in solidification that could even result in melting in some regions of the inner core boundary. It has also been hypothesized that the inner core is growing dendritically, resulting in an inner core that has the structure of a mushy zone (albeit one with a high solid fraction). It would therefore be helpful to understand how the structure of a melting mushy zone might look in comparison with one that is solidifying, in an effort to help interpret the seismic inferences. We have carried out experiments on the solidification of ammonium chloride from an aqueous solution, yielding a mushy zone. The experiments run in a centrifuge, in order to reach a more realistic ratio of convective velocity to phase change rate, expected to be very large at the boundary of the inner core. Hypergravity thus increases the experimental solid fraction of the mush. So far the maximum gravity we have achieved is 200 g. A Peltier cell provides cooling at one end of the cell, and after the mushy zone has grown we turn on a heater at the other end. Probes monitor the temperature along the height of the cell. As ammonium chloride in the mushy zone melts it produces more dense fluid, which results in convection in the mushy zone, a greater ammonium chloride concentration deeper in the mushy zone, and hence enhanced solidification there. This thus changes the solid fraction profile from that during solidification, which may be observable in the lab experiments using ultrasonic transducers and post-mortem under a microscope. The melting may also change the propagation of chimney convection. It remains unclear whether these changes will be observable seismically.

  12. The WAIS Melt Monitor: An automated ice core melting system for meltwater sample handling and the collection of high resolution microparticle size distribution data

    NASA Astrophysics Data System (ADS)

    Breton, D. J.; Koffman, B. G.; Kreutz, K. J.; Hamilton, G. S.

    2010-12-01

    Paleoclimate data are often extracted from ice cores by careful geochemical analysis of meltwater samples. The analysis of the microparticles found in ice cores can also yield unique clues about atmospheric dust loading and transport, dust provenance and past environmental conditions. Determination of microparticle concentration, size distribution and chemical makeup as a function of depth is especially difficult because the particle size measurement either consumes or contaminates the meltwater, preventing further geochemical analysis. Here we describe a microcontroller-based ice core melting system which allows the collection of separate microparticle and chemistry samples from the same depth intervals in the ice core, while logging and accurately depth-tagging real-time electrical conductivity and particle size distribution data. This system was designed specifically to support microparticle analysis of the WAIS Divide WDC06A deep ice core, but many of the subsystems are applicable to more general ice core melting operations. Major system components include: a rotary encoder to measure ice core melt displacement with 0.1 millimeter accuracy, a meltwater tracking system to assign core depths to conductivity, particle and sample vial data, an optical debubbler level control system to protect the Abakus laser particle counter from damage due to air bubbles, a Rabbit 3700 microcontroller which communicates with a host PC, collects encoder and optical sensor data and autonomously operates Gilson peristaltic pumps and fraction collectors to provide automatic sample handling, melt monitor control software operating on a standard PC allowing the user to control and view the status of the system, data logging software operating on the same PC to collect data from the melting, electrical conductivity and microparticle measurement systems. Because microparticle samples can easily be contaminated, we use optical air bubble sensors and high resolution ice core density profiles to guide the melting process. The combination of these data allow us to analyze melt head performance, minimize outer-to-inner fraction contamination and avoid melt head flooding. The WAIS Melt Monitor system allows the collection of real-time, sub-annual microparticle and electrical conductivity data while producing and storing enough sample for traditional Coulter-Counter particle measurements as well long term acid leaching of bioactive metals (e.g., Fe, Co, Cd, Cu, Zn) prior to chemical analysis.

  13. Estimates of early containment loads from core melt accidents. Draft report for comment

    SciTech Connect

    none,

    1985-12-01

    The thermal-hydraulic processes and corium debris-material interactions that can result from core melting in a severe accident have been studied to evaluate the potential effect of such phenomena on containment integrity. Pressure and temperature loads associated with representative accident sequences have been estimated for the six various LWR containment types used within the United States. Summaries distilling the analyses are presented and an interpretation of the results provided. 13 refs., 68 figs., 39 tabs.

  14. Hot-melt extruded ethylcellulose cylinders containing a HPMC–Gelucire® core for sustained drug delivery

    Microsoft Academic Search

    E Mehuys; C Vervaet; J. P Remon

    2004-01-01

    The objective of the study was to develop a sustained release system consisting of a hot-melt extruded ethylcellulose pipe surrounding a drug-containing hydroxypropyl methylcellulose (HPMC)–Gelucire® 44\\/14 core, yielding a monolithic matrix system applicable in the domain of sustained drug release. The influence of HPMC substitution type and viscosity grade was investigated through dissolution testing and erosion studies. All sustained release

  15. Can random pinning change the melting scenario of two-dimensional core-softened potential system?

    E-print Network

    E. N. Tsiok; D. E. Dudalov; Yu. D. Fomin; V. N. Ryzhov

    2015-07-07

    In experiments the two-dimensional systems are realized mainly on solid substrates which introduce quenched disorder due to some inherent defects. The defects of substrates influence the melting scenario of the systems and have to be taken into account in the interpretation of the experimental results. We present the results of the molecular dynamics simulations of the two dimensional system with the core-softened potential in which a small fraction of the particles is pinned, inducing quenched disorder.The potentials of this type are widely used for the qualitative description of the systems with the water-like anomalies. In our previous publications it was shown that the system demonstrates an anomalous melting scenario: at low densities the system melts through two continuous transition in accordance with the Kosterlitz-Thouless-Halperin-Nelson-Young (KTHNY) theory with the intermediate hexatic phase, while at high densities the conventional first order melting transition takes place. We find that the well-known disorder-induced widening of the hexatic phase occurs at low densities, while at high density part of the phase diagram random pinning transforms the first-order melting into two transitions: the continuous KTHNY-like solid-hexatic transition and first-order hexatic-isotropic liquid transition.

  16. Sulfur Saturation Limits in Silicate Melts and their Implications for Core Formation Scenarios for Terrestrial Planets

    NASA Technical Reports Server (NTRS)

    Holzheid, Astrid; Grove, Timothy L.

    2002-01-01

    This study explores the controls of temperature, pressure, and silicate melt composition on S solubility in silicate liquids. The solubility of S in FeO-containing silicate melts in equilibrium with metal sulfide increases significantly with increasing temperature but decreases with increasing pressure. The silicate melt structure also exercises a control on S solubility. Increasing the degree of polymerization of the silicate melt structure lowers the S solubility in the silicate liquid. The new set of experimental data is used to expand the model of Mavrogenes and O'Neill(1999) for S solubility in silicate liquids by incorporating the influence of the silicate melt structure. The expected S solubility in the ascending magma is calculated using the expanded model. Because the negative pressure dependence of S solubility is more influential than the positive temperature dependence, decompression and adiabatic ascent of a formerly S-saturated silicate magma will lead to S undersaturation. A primitive magma that is S-saturated in its source region will, therefore, become S-undersaturated as it ascends to shallower depth. In order to precipitate magmatic sulfides, the magma must first cool and undergo fractional crystallization to reach S saturation. The S content in a metallic liquid that is in equilibrium with a magma ocean that contains approx. 200 ppm S (i.e., Earth's bulk mantle S content) ranges from 5.5 to 12 wt% S. This range of S values encompasses the amount of S (9 to 12 wt%) that would be present in the outer core if S is the light element. Thus, the Earth's proto-mantle could be in equilibrium (in terms of the preserved S abundance) with a core-forming metallic phase.

  17. Sulfur Saturation Limits in Silicate Melts and their Implications for Core Formation Scenarios for Terrestrial Planets

    NASA Technical Reports Server (NTRS)

    Holzheid, Astrid; Grove, Timothy L.

    2003-01-01

    This study explores the controls of temperature, pressure, and silicate melt composition on S solubility in silicate liquids. The solubility of S in FeO-containing silicate melts in equilibrium with metal sulfide increases significantly with increasing temperature but decreases with increasing pressure. The silicate melt structure also exercises a control on S solubility. Increasing the degree of polymerization of the silicate melt structure lowers the S solubility in the silicate liquid. The new set of experimental data is used to expand the model of Mavrogenes and O Neill (1999) for S solubility in silicate liquids by incorporating the influence of the silicate melt structure. The expected S solubility in the ascending magma is calculated using the expanded model. Because the negative pressure dependence of S solubility is more influential than the positive temperature dependence, decompression and adiabatic ascent of a formerly S-saturated silicate magma will lead to S undersaturation. A primitive magma that is S-saturated in its source region will, therefore, become S-undersaturated as it ascends to shallower depth. In order to precipitate magmatic sulfides, the magma must first cool and undergo fractional crystallization to reach S saturation. The S content in a metallic liquid that is in equilibrium with a magma ocean that contains -200 ppm S (Le., Earth s bulk mantle S content) ranges from 5.5 to 12 wt% S. This range of S values encompasses the amount of S (9 to 12 wt%) that would be present in the outer core if S is the light element. Thus, the Earth s proto-mantle could be in equilibrium (in terms of the preserved S abundance) with a core-forming metallic phase.

  18. Chemical Convection in the Lunar Core from Melting Experiments on the Fe-Ni-S System

    NASA Astrophysics Data System (ADS)

    Liu, J.; Chen, B.; Wang, Y.; Jing, Z.; Li, Z.; Li, J.

    2012-12-01

    The thermal and chemical states of the lunar interior are directly related to the origin and evolution of the Moon. Recent seismic study suggested the lunar core is partially molten, consisting of a liquid outer shell and a solid inner sphere (Weber et al., 2011). The volume fraction of the lunar inner core is 38%, which is much higher than that for the Earth (~ 4%). This volume fraction can be used to establish the relation between the bulk composition of the lunar core and its temperature profile if the liquidi of relevant compositions at lunar inner core boundary (ICB) pressure (~ 5.1 GPa) are known. Moreover, knowledge on the extent of core solidification can be used to evaluate the role of compositional convection in the origin of early lunar core dynamo (Stegman et al., 2003). We have conducted melting experiments at 5.1 GPa and 900-1600 °C for the Fe-rich portion of Fe-Ni-S system, using the multi-anvil apparatus and synchrotron and laboratory-based analytical methods. Our data show that in the iron-rich portion of the Fe-S binary system, the liquidus curve reflects nearly ideal mixing between iron and FeS end-members. In contrast, the liquidus curve of the Fe-Ni-S ternary contains two inflection points with a turning point at a sulfur content of 10 wt.%, resulting from a departure from ideal solution behavior. Given that the compositional buoyancy force scales with the slope of the liquidus curve at the ICB pressure and temperature, the contribution of compositional convection to sustain the early lunar dynamo can be estimated from our data: for a simplified model of Fe-S binary core, the role of chemical convection was probably negligible in the early history of the Moon and would have remained nearly constant since the inception of the inner core. The lunar core, however, likely contains nickel, the turning points in liquidus curve of the Fe-Ni-S ternary system may lead to dynamo initiation if the sulfur content of the bulk lunar core is less than 10 wt.% or cessation if the bulk lunar core contains more than 10 wt.% sulfur. References Stegman, D.R., Jellinek, A.M., Zatman, S.A., Baumgardner, J.R., and Richards, M.A. (2003) An early lunar core dynamo driven by thermochemical mantle convection. Nature, 421(6919), 143-146. Weber, R.C., Lin, P.Y., Garnero, E.J., Williams, Q., and Lognonne, P. (2011) Seismic Detection of the Lunar Core. Science, 331(6015), 309-312.

  19. Comparison of the effect of hazard and response/fragility uncertainties on core melt probability uncertainty

    SciTech Connect

    Mensing, R.W.

    1985-01-01

    This report proposes a method for comparing the effects of the uncertainty in probabilistic risk analysis (PRA) input parameters on the uncertainty in the predicted risks. The proposed method is applied to compare the effect of uncertainties in the descriptions of (1) the seismic hazard at a nuclear power plant site and (2) random variations in plant subsystem responses and component fragility on the uncertainty in the predicted probability of core melt. The PRA used is that developed by the Seismic Safety Margins Research Program.

  20. Diverse melting modes and structural collapse of hollow bimetallic core-shell nanoparticles: a perspective from molecular dynamics simulations.

    PubMed

    Huang, Rao; Shao, Gui-Fang; Zeng, Xiang-Ming; Wen, Yu-Hua

    2014-01-01

    Introducing hollow structures into metallic nanoparticles has become a promising route to improve their catalytic performances. A fundamental understanding of thermal stability of these novel nanostructures is of significance for their syntheses and applications. In this article, molecular dynamics simulations have been employed to offer insights into the thermodynamic evolution of hollow bimetallic core-shell nanoparticles. Our investigation reveals that for hollow Pt-core/Au-shell nanoparticle, premelting originates at the exterior surface, and a typical two-stage melting behavior is exhibited, similar to the solid ones. However, since the interior surface provides facilitation for the premelting initiating at the core, the two-stage melting is also observed in hollow Au-core/Pt-shell nanoparticle, remarkably different from the solid one. Furthermore, the collapse of hollow structure is accompanied with the overall melting of the hollow Pt-core/Au-shell nanoparticle while it occurs prior to that of the hollow Au-core/Pt-shell nanoparticle and leads to the formation of a liquid-core/solid-shell structure, although both of them finally transform into a mixing alloy with Au-dominated surface. Additionally, the existence of stacking faults in the hollow Pt-core/Au-shell nanoparticle distinctly lowers its melting point. This study could be of great importance to the design and development of novel nanocatalysts with both high activity and excellent stability. PMID:25394424

  1. Interpretation of experimental results from the CORA core melt progression experiments

    SciTech Connect

    Hohorst, J.K.; Allison, C.M.

    1991-01-01

    Data obtained from the CORA bundle heatup and melting experiments, performed at Kernforschungszentrum, Karlsruhe, Germany, are being analyzed at the Idaho National Engineering Laboratory. The analysis is being performed as part of a systematic review of core melt progression experiments for the United States Nuclear Regulatory Commission to (a) develop an improved understanding of important phenomena occurring during a severe accident, (b) to validate existing severe accident models, and (c) where necessary, develop improved models. An assessment of the variations in damage progression behavior because of variations in test parameters (a) bundle design and size, (b) system pressure, (c) slow cooling of the damaged bundles in argon versus rapid quenching in water, and (d) bundle inlet temperatures and flow rates is provided in the paper. The influence of uncertainties in important test conditions is also discussed. Specific results presented include (a) bundle temperature, (b) the onset and movement of the oxidation front within the bundle, (c) fuel rod ballooning and rod failure, and (d) melt relocation and associated material interactions between bundle components and structures. 12 refs., 16 figs., 2 tabs.

  2. Nickel and helium evidence for melt above the core-mantle boundary.

    PubMed

    Herzberg, Claude; Asimow, Paul D; Ionov, Dmitri A; Vidito, Chris; Jackson, Matthew G; Geist, Dennis

    2013-01-17

    High (3)He/(4)He ratios in some basalts have generally been interpreted as originating in an incompletely degassed lower-mantle source. This helium source may have been isolated at the core-mantle boundary region since Earth's accretion. Alternatively, it may have taken part in whole-mantle convection and crust production over the age of the Earth; if so, it is now either a primitive refugium at the core-mantle boundary or is distributed throughout the lower mantle. Here we constrain the problem using lavas from Baffin Island, West Greenland, the Ontong Java Plateau, Isla Gorgona and Fernandina (Galapagos). Olivine phenocryst compositions show that these lavas originated from a peridotite source that was about 20 per cent higher in nickel content than in the modern mid-ocean-ridge basalt source. Where data are available, these lavas also have high (3)He/(4)He. We propose that a less-degassed nickel-rich source formed by core-mantle interaction during the crystallization of a melt-rich layer or basal magma ocean, and that this source continues to be sampled by mantle plumes. The spatial distribution of this source may be constrained by nickel partitioning experiments at the pressures of the core-mantle boundary. PMID:23302797

  3. Partitioning of Moderately Siderophile Elements Among Olivine, Silicate Melt, and Sulfide Melt: Constraints on Core Formation in the Earth and Mars

    NASA Technical Reports Server (NTRS)

    Gaetani, Glenn A.; Grove, Timothy L.

    1997-01-01

    This study investigates the effects of Variations in the fugacities of oxygen and sulfur on the partitioning of first series transition metals (V, Cr, Mn, Fe, Co, Ni. and Cu) and W among coexisting sulfide melt, silicate melt, and olivine. Experiments were performed at 1 atm pressure, 1350 C, with the fugacities of oxygen and sulfur controlled by mixing CO2, CO, and SO2 gases. Starting compositions consisted of a CaO-MgO-Al2O3-SiO2-FeO-Na2O analog for a barred olivine chondrule from an ordinary chondrite and a synthetic komatiite. The f(sub O2)/f(sub S2), conditions ranged from log of f(sub O2) = -7.9 to - 10.6, with log of f(sub S2) values ranging from - 1.0 to -2.5. Our experimental results demonstrate that the f(sub O2)/f(sub S2) dependencies of sulfide melt/silicate melt partition coefficients for the first series transition metals arc proportional to their valence states. The f(sub O2)/f(sub S2) dependencies for the partitioning of Fe, Co, Ni, and Cu are weaker than predicted on the basis of their valence states. Variations in conditions have no significant effect on olivine/melt partitioning other than those resulting from f(sub O2)-induced changes in the valence state of a given element. The strong f(sub O2)/f(sub S2) dependence for the olivine/silicate melt partitioning of V is attributable to a change of valence state, from 4+ to 3+, with decreasing f(sub O2). Our experimentally determined partition coefficients are used to develop models for the segregation of sulfide and metal from the silicate portion of the early Earth and the Shergottite parent body (Mars). We find that the influence of S is not sufficient to explain the overabundance of siderophile and chalcophile elements that remained in the mantle of the Earth following core formation. Important constraints on core formation in Mars are provided by our experimental determination of the partitioning of Cu between silicate and sulfide melts. When combined with existing estimates for siderophile element abundances in the Martian mantle and a mass balance constraint from Fe, the experiments allow a determination of the mass of the Martian core (approx. 17 to 22 wt% of the planet) and its S content (approx.0.4 wt%). These modeling results indicate that Mars is depleted in S, and that its core is solid.

  4. Constraints on core formation from molybdenum solubility in silicate melts at high pressure

    NASA Astrophysics Data System (ADS)

    Burkemper, Laura K.; Agee, Carl B.; Garcia, Kody A.

    2012-06-01

    We report results from 43 new molybdenum solubility experiments performed in order to test molybdenum's compatibility with the magma ocean hypothesis for core formation. A Walker-type multi-anvil press was used for all experiments and we investigated the pressure range of 2.5-12 GPa and temperature range of 1585-2200 °C. Eight different silicate compositions were also employed. Our data show that increasing temperature causes solubility to increase, whereas pressure has a negligible effect over the range investigated here. In general, increasing silicate melt polymerization causes solubility to decrease; however, the effect of silicate composition is best addressed by looking at the effects of individual oxides versus a universal melt parameter such as NBO/T (ratio of non-bridging oxygens to tetrahedrally coordinated oxygens). From our solubility data, we calculated metal-silicate partition coefficients at infinite iron dilution. Parameterization of our data plus data from the literature shows that there is no discrepancy between partition coefficients determined directly from experiments and those calculated from solubility data, so long as all variables are taken into account, i.e. changes in metal phase composition. Additionally, most of the experiments in the literature were conducted at pressures below 2 GPa, therefore the addition of our high pressure data set makes extrapolations to deep magma ocean conditions more accurate. We determined that the observed mantle abundance of Mo can be explained by both single-stage and multi-stage magma ocean models. Previous siderophile element studies have suggested a wide range of possible single-stage core formation conditions, from 10 to 60 GPa along the peridotite liquidus. Our results narrowed this range by constraining the P-T conditions to 40-54 GPa and 3050-3400 K. Our results also further constrained the multi-stage core formation models by limiting the depth of metal-silicate equilibration during the final impacts of accretion to 31-42% of the core-mantle boundary depth.

  5. Melting behavior of the iron-sulfur system and chemical convection in iron-rich planetary cores

    SciTech Connect

    Li, J.; Chen, B. (UIUC)

    2009-03-26

    We present experimental data on the high-pressure melting behavior of the Fe-S system from a synchrotron x-ray radiography study using the large volume press, with implications for the role of chemical convection in sulfur-bearing planetary cores. At present, Earth, Mercury and Ganymede are the only three solid bodies in the Solar System that possess intrinsic global magnetic fields. Dynamo simulation reveal that chemical buoyancy force associated with the formation of a solid inner core is critical for sustaining the Earth's magnetic field. Fluid motions in Mercury and Ganymede may be partially driven by chemical buoyancy force as well. The style of chemical convection and its influence on the thermal and chemical state and evolution of iron-rich cores are determined in part by the melting behavior of potential core-forming materials. Sulfur is widely accepted as a candidate light element in iron-rich planetary cores. In order to understand the role of chemical convection in sulfur-bearing cores, we studied the high-pressure melting behavior of Fe-S mixtures containing 9 wt% sulfur using the synchrotron x-ray radiographic method in a large volume press.

  6. Melting of iron close to Earth's inner core boundary conditions detected by XANES spectroscopy in laser shock experiment

    NASA Astrophysics Data System (ADS)

    Morard, G.; Harmand, M.; Ravasio, A.; Mazevet, S.; Bouchet, J.; Denoeud, A.; Dorchies, F.; Fourment, C.; Galtier, E.; Gaudin, J.; Guyot, F. J.; Koenig, M.; Miyanishi, K.; Musella, R.; Nagler, B.; Lee, H. J.; Nakatsutsumi, M.; Ozaki, N.; Recoules, V.; Toleikis, S.; Vinci, T.; Zastrau, U.; Feng, Y.; Zhu, D.; Benuzzi, A.

    2014-12-01

    When modeling the Earth's interior, essential features lie in our knowledge of iron and iron alloys physical properties at extreme pressures and temperatures. While the density profile of the Earth's interior is rather well constrained from seismic data, the temperature at the boundary between the solid inner core and liquid outer core (ICB, Inner Core Boundary), where the pressure is estimated to be of 330GPa, remains up to now largely uncertain. It corresponds to the melting temperature of an iron alloy containing a small but unconstrained amount of impurities [1]. As a reference, the melting temperature of pure iron at ICB pressure condition is thus one of the most important parameters of earth and planetary interiors physics. For that reason, measuring the iron melting curve at conditions corresponding to the Earth Inner Core Boundary (ICB) under pressure of 330GPa has eluded scientists for several decades. Here we used X-ray Absorption Near Edge Structure (XANES) spectroscopy with ultrafast X-ray Free Electron Laser (XFEL) sources coupled to a laser shock experiment, to detect the state of iron along the shock Hugoniot up to 420GPa (+/- 50) and 10800K (+/- 1390). Our results allows to put an upper constrain on the high pressure-melting curve of iron by detecting well beyond recent diamond-anvil cell measurements performed at 150GPa [2]. [1] J.P. Poirier, Phys. Earth Planet. Int. 85, 319 (1994). [2] S. Anzellini et al., Science 340, 464 (2013).

  7. Melting phase relation of FeH x up to 20 GPa: Implication for the temperature of the Earth's core

    NASA Astrophysics Data System (ADS)

    Sakamaki, K.; Takahashi, E.; Nakajima, Y.; Nishihara, Y.; Funakoshi, K.; Suzuki, T.; Fukai, Y.

    2009-05-01

    High-pressure and high-temperature X-ray diffraction experiments on FeH x up to 20 GPa and 1598 K were performed using a Kawai-type multi-anvil apparatus, SPEED-MkII, installed at BL04B1 beam line of SPring-8 synchrotron facility. Iron powder was packed in a container made of NaCl, a very efficient sealing material for hydrogen under high pressure, together with a hydrogen source, LiAlH 4. The temperature of hydrogenation, transition of iron hydride phases, and melting of ?-FeH x were all determined in situ in the pressure range between 10 and 20 GPa. Hydrogen concentration in both ?'- and ?-FeH x phases reached x = 1.0 above 10 GPa. Melting temperatures of ?-FeH were determined to be 1473, 1448 ± 25, 1538 ± 15, 1548 ± 25 and 1585 ± 13 K at 10, 11.5, 15, 18 and 20 GPa, respectively. These temperatures are nearly 700 K lower than that of pure iron under the corresponding pressures. The Clapeyron-slope (d T/d P slope) of the melting curve of ?-FeH is 13 K/GPa, which is significantly smaller than those of other possible core constituents (Fe, FeO, FeS). By extrapolating the ?'-? phase boundary linearly and the melting curve of ?-FeH based on Lindemann's melting law, the triple point of ?'- and ?-FeH and iron hydride melt is located at P = 60 GPa and T = 2000 K. Beyond the triple point, an attempt to construct a melting curve of ?'-FeH by the Lindemann's law using estimated thermal equation of state of ?'-FeH was unsuccessful. Therefore, we decided, instead, to extrapolate the melting curve of ?-FeH beyond the triple point to 135 GPa yielding the melting temperature of FeH ˜ 2600 K at core mantle boundary (CMB). Based on these results, we propose that the temperature of the Earth's outer core could be much lower than current estimates, if the Earth's outer core incorporated significant amounts of hydrogen.

  8. Simulant Melt Experiments on Performance of the In-Vessel Core Catcher

    SciTech Connect

    Kyoung-Ho Kang; Rae-Joon Park; Sang-Baik Kim; K. Y. Suh; F. B. Cheung; J. L. Rempe

    2007-09-01

    In order to enhance the feasibility of in-vessel retention (IVR) of molten core material during a severe accident for high-power reactors, an in-vessel core catcher (IVCC) was designed and evaluated as part of a joint United States-Korean International Nuclear Energy Research Initiative (INERI). The proposed IVCC is expected to increase the thermal margin for success of IVR by providing an “engineered gap” for heat transfer from materials that relocate during a severe accident and potentially serving as a sacrificial material under a severe accident. In this study, LAVA-GAP experiments were performed to investigate the thermal and mechanical performance of the IVCC using the alumina melt as simulant. The LAVAGAP experiments aim to examine the feasibility and sustainability of the IVCC under the various test conditions using 1/8th scale hemispherical test sections. As a feasibility test of the proposed IVCC in this INERI project, the effects of IVCC base steel materials, internal coating materials, and gap size between the IVCC and the vessel lower head were examined. The test results indicated that the internally coated IVCC has high thermal performance compared with the uncoated IVCC. In terms of integrity of the base steel, carbon steel is superior to stainless steel and the effect of bond coat is found to be trivial for the tests performed in this study. The thermal load is mitigated via boiling heat removal in the gap between the IVCC and the vessel lower head. The current test results imply that gaps less than 10mm are not enough to guarantee effective cooling induced by water ingression and steam venting there through. Selection of endurable material and pertinent gap size is needed to implement the proposed IVCC concept into advanced reactor designs.

  9. Ice Core Evidence of Recent Changes in Summer Melt Intensity of the Southern Greenland Ice Sheet

    Microsoft Academic Search

    S. B. Das; M. A. Fahnestock; J. McConnell; E. Hanna; K. Steffen; J. E. Box

    2004-01-01

    Knowledge of past Greenland Ice Sheet surface melting extent and intensity, and associated climatic controls, is critical to understanding the current and future mass balance of the ice sheet. Surface melting is greatest along the margins of the Greenland Ice Sheet, but leaves no simple record of past patterns or intensity at low elevations. This makes it difficult to place

  10. Rapid, dynamic segregation of core forming melts: Results from in-situ High Pressure- High Temperature X-ray Tomography

    NASA Astrophysics Data System (ADS)

    Watson, H. C.; Yu, T.; Wang, Y.

    2011-12-01

    The timing and mechanisms of core formation in the Earth, as well as in Earth-forming planetesimals is a problem of significant importance in our understanding of the early evolution of terrestrial planets . W-Hf isotopic signatures in meteorites indicate that core formation in small pre-differentiated planetesimals was relatively rapid, and occurred over the span of a few million years. This time scale is difficult to achieve by percolative flow of the metallic phase through a silicate matrix in textural equilibrium. It has been suggested that during this active time in the early solar system, dynamic processes such as impacts may have caused significant deformation in the differentiating planetesimals, which could lead to much higher permeability of the core forming melts. Here, we have measured the change in permeability of core forming melts in a silicate matrix due to deformation. Mixtures of San Carlos olivine and FeS close to the equilibrium percolation threshold (~5 vol%FeS) were pre-synthesized to achieve an equilibrium microstructure, and then loaded into the rotational Drickamer apparatus at GSE-CARS, sector 13-BMD, at the Advanced Photon Source (Argonne National Laboratory). The samples were subsequently pressed to ~2GPa, and heated to 1100°C. Alternating cycles of rotation to collect X-ray tomography images, and twisting to deform the sample were conducted until the sample had been twisted by 1080°. Qualitative and quantitative analyses were performed on the resulting 3-dimensional x-ray tomographic images to evaluate the effect of shear deformation on permeability and migration velocity. Lattice-Boltzmann simulations were conducted, and show a marked increase in the permeability with increasing deformation, which would allow for much more rapid core formation in planetesimals.

  11. Uranium partitioning between liquid iron and silicate melt at high pressures: implications for uranium solubility in planetary cores

    E-print Network

    Bao, X; Gagnon, J E; Fryer, B J; Bao, Xuezhao; Secco, Richard A.; Gagnon, Joel E.; Fryer, Brian J.

    2006-01-01

    We have investigated the partitioning of U between silicate melt and Fe liquid at pressures of 3.0 to14.5 GPa and temperatures of 1660 to 2500 oC. The solubility of U in liquid Fe is in the range of 0.6 to 800 ppm and increases with temperature (T) and pressure (P). When P = or > 7 GPa and T > Tmelt of the silicate phase (olivine), the U concentration in Fe is 3 to 5 times greater than for run products where T Tmelt of the silicate phase), then > 2.4 ppb U could have entered the core. Alternatively, if a core with same composition formed by percolation (T alloy with Fe directly. If Si concentration in the Fe phase can be used as an indicator of oxygen fugaci...

  12. Uranium partitioning between liquid iron and silicate melt at high pressures: implications for uranium solubility in planetary cores

    E-print Network

    Xuezhao Bao; Richard A. Secco; Joel E. Gagnon; Brian J. Fryer

    2006-06-29

    We have investigated the partitioning of U between silicate melt and Fe liquid at pressures of 3.0 to14.5 GPa and temperatures of 1660 to 2500 oC. The solubility of U in liquid Fe is in the range of 0.6 to 800 ppm and increases with temperature (T) and pressure (P). When P = or > 7 GPa and T > Tmelt of the silicate phase (olivine), the U concentration in Fe is 3 to 5 times greater than for run products where T Tmelt of the silicate phase), then > 2.4 ppb U could have entered the core. Alternatively, if a core with same composition formed by percolation (T < Tmelt of the silicate phase), then based on the experimental results indicating DU increases with increasing P, 1 to 4 ppb U may have entered the core. The concentration of Si in liquid Fe also increases with pressure. The concentration of Ca is < 0.44 wt % for most samples and no relation with U concentration is found, which indicates that U may alloy with Fe directly. If Si concentration in the Fe phase can be used as an indicator of oxygen fugacity, then the increase in Si and U with pressure suggests a pressure dependent decrease in oxygen fugacity. This supports U (and possibly also Si) inclusion in the the core of Earth at the time of core formation. The implications for radioactive heating in the planetary cores are briefly discussed. Keywords: Uranium; partition coefficients; high pressure; dynamos; planetary cores; heat sources, LA-ICP-MS.

  13. Creep rupture behavior of a PWR lower head in a core-melt accident

    SciTech Connect

    Jeong, Kwang Jin; Lim, Dong Cheol; Hwang, Il Soon [Seoul National Univ. (Korea, Republic of)

    1997-12-01

    Although the Three Mile Island unit 2 (TMI-2) vessel did not fail, code analyses in support of the Organization for Economic Cooperation and Development/Nuclear Energy Agency TMI-2 Vessel Investigation Project generally predicted creep rupture for these conditions. This fueled speculation that there might be some inherent mechanism not previously recognized that could delay or prevent lower head failure. The most widely held belief is that the relocated melt did not adhere to the lower head; consequently, there should be gaps between the inside surface of the vessel and the relocated melt. These gaps, perhaps widened by temperature-induced creep of the lower head, provide a channel for water intrusion and subsequent quenching of the head, preventing its creep rupture. Therefore, from both accident assessment and accident mitigation considerations, there is a need to understand the mechanism of lower head creep and rupture.

  14. Melt-grafting for the synthesis of core-shell nanoparticles with ultra-high dispersant density.

    PubMed

    Zirbs, Ronald; Lassenberger, Andrea; Vonderhaid, Iris; Kurzhals, Steffen; Reimhult, Erik

    2015-07-01

    Superparamagnetic iron oxide nanoparticles (NPs) are used in a rapidly expanding number of applications in e.g. the biomedical field, for which brushes of biocompatible polymers such as poly(ethylene glycol) (PEG) have to be densely grafted to the core. Grafting of such shells to monodisperse iron oxide NPs has remained a challenge mainly due to the conflicting requirements to replace the ligand shell of as-synthesized NPs with irreversibly bound PEG dispersants. We introduce a general two-step method to graft PEG dispersants from a melt to iron oxide NPs first functionalized with nitrodopamine (NDA). This method yields uniquely dense spherical PEG-brushes (?3 chains per nm(2) of PEG(5 kDa)) compared to existing methods, and remarkably colloidally stable NPs also under challenging conditions. PMID:26061616

  15. Crystallization Processes in Mercury's Core Inferred from In-situ High-Pressure Melting Experiments in the Fe-S-Si-C System

    NASA Astrophysics Data System (ADS)

    Martin, A. M.; Van Orman, J. A.; Hauck, S. A., II; Sun, N.; Yu, T.; Wang, Y.

    2014-12-01

    Based upon the high pressure melting temperatures in the Fe-FeS system, an iron "snow" process has been suggested to occur in Mercury's core. However, recent results from the MESSENGER mission indicate very reducing conditions in Mercury, under which a substantial amount of silicon should also dissolve into the core. The presence of Si can significantly modify the chemical and physical properties of Mercury's core (e.g., phase relations, crystallization, density). Moreover, up to 4 wt% C could have been incorporated into the core during the planet formation. In order to test the iron snow hypothesis in a system that is likely to be closer to the actual core composition, we performed in situ high-pressure, high-temperature experiments in the Fe-FeS-Fe2Si-Fe3C system using a multi-anvil press on a synchrotron (Advanced Photon Source, Argonne). To observe low degree eutectic melting, we separated the samples in two parts: (1) an iron rod presaturated with Si and C and (2) a mixture of FeS, Fe2Si and Fe3C. Eutectic melting temperature and phase relations were determined at various pressures between 4.5 and 15.5 GPa using energy dispersive X-ray diffraction and imaging. Temperature was quenched soon after melting in order to preserve the eutectic melt composition. The X-ray images, diffraction spectra and back-scattered electron images of the recovered samples show that eutectic melting occurs in the range of 800 - 900°C in all our experiments. These temperatures are close to the eutectic temperatures in the Fe-FeS-Fe3C system, indicating that Si does not change the eutectic temperatures significantly. Melting therefore occurs at much lower temperature than suggested for the Fe-S-Si system at similar pressures. This difference may be explained by the presence of C and by the higher silicon content in our starting composition. Our experimental setup may also be more suitable for detecting the low degrees of melting in metallic systems. Such low eutectic melting temperatures imply that the iron "snow" process may still be valid even if silicon and carbon are present in Mercury's core.

  16. Melt-grafting for the synthesis of core-shell nanoparticles with ultra-high dispersant density

    NASA Astrophysics Data System (ADS)

    Zirbs, Ronald; Lassenberger, Andrea; Vonderhaid, Iris; Kurzhals, Steffen; Reimhult, Erik

    2015-06-01

    Superparamagnetic iron oxide nanoparticles (NPs) are used in a rapidly expanding number of applications in e.g. the biomedical field, for which brushes of biocompatible polymers such as poly(ethylene glycol) (PEG) have to be densely grafted to the core. Grafting of such shells to monodisperse iron oxide NPs has remained a challenge mainly due to the conflicting requirements to replace the ligand shell of as-synthesized NPs with irreversibly bound PEG dispersants. We introduce a general two-step method to graft PEG dispersants from a melt to iron oxide NPs first functionalized with nitrodopamine (NDA). This method yields uniquely dense spherical PEG-brushes (~3 chains per nm2 of PEG(5 kDa)) compared to existing methods, and remarkably colloidally stable NPs also under challenging conditions.Superparamagnetic iron oxide nanoparticles (NPs) are used in a rapidly expanding number of applications in e.g. the biomedical field, for which brushes of biocompatible polymers such as poly(ethylene glycol) (PEG) have to be densely grafted to the core. Grafting of such shells to monodisperse iron oxide NPs has remained a challenge mainly due to the conflicting requirements to replace the ligand shell of as-synthesized NPs with irreversibly bound PEG dispersants. We introduce a general two-step method to graft PEG dispersants from a melt to iron oxide NPs first functionalized with nitrodopamine (NDA). This method yields uniquely dense spherical PEG-brushes (~3 chains per nm2 of PEG(5 kDa)) compared to existing methods, and remarkably colloidally stable NPs also under challenging conditions. Electronic supplementary information (ESI) available: The ESI contains details on additional synthetic protocols and characterization. See DOI: 10.1039/c5nr02313k

  17. Molecular dynamics simulations on the melting, crystallization, and energetic reaction behaviors of Al/Cu core-shell nanoparticles

    NASA Astrophysics Data System (ADS)

    Cheng, Xin-Lu; Zhang, Jin-Ping; Zhang, Hong; Zhao, Feng

    2013-08-01

    Using molecular dynamics simulations combined with the embedded atom method potential, we investigate the heating, cooling, and energetic reacting of core-shell structured Al-Cu nanoparticles. The thermodynamic properties and structure evolution during continuous heating and cooling processes are also investigated through the characterization of the total potential energy distribution, mean-square-distance and radial distribution function. Some behaviors related to nanometer scale Cu/Al functional particles are derived that two-way diffusion of Al and Cu atoms, glass phase formation for the fast cooling rate, and the crystal phase formation for the low cooling rate. Two-way atomic diffusion occurs first and causes the melting and alloying. In the final alloying structure, Cu and Al atoms mixed very well except for the outmost shell which has more Al atoms. For the investigation of the thermal stability and energetic reaction properties, our study show that a localized alloying reaction between the Al core and Cu shell is very slow when the initial temperature is lower than 600 K. But a two-stage reaction may occur when the initial temperature is 700 K. The reaction rate is determined by the solid-state diffusion of Al atoms in the Cu shell at the first stage, yet the reaction rate is much faster at the second stage, due to the alloying reaction between the liquid Al core and the Cu shell. At higher temperatures such as 800 K and 900 K, the alloying reaction occurs directly between the liquid Al core and the Cu shell.

  18. Martorell, B; Vocadlo, L; Brodholt, J; Wood, IG (2013); Strong pre-melting effect in the elastic properties of hcp-Fe under inner-core conditions, Science 342:6157; 466-468.

    E-print Network

    Crawford, Ian

    2013-01-01

    of Fe may soften dramatically and non-linearly very near to its melting point (Tm), as has been observed shown to decrease by more than 50% at temperatures within about 1% of its melting point (13,14). According to ab initio simulations, the melting point of pure Fe at the conditions of the inner core

  19. Basal Melt Under the Interior of the Greenland Ice Sheet: Comparison of Models, Deep Ice Cores, and Radar Observations

    NASA Astrophysics Data System (ADS)

    Rezvanbehbahani, S.; Stearns, L. A.; van der Veen, C. J.

    2014-12-01

    Basal ice temperature is a critical boundary condition for ice sheet models. It modulates the basal melt rate and sliding conditions, and also affects the ice hardness which alters the deformational velocity. Therefore, in order to obtain reliable estimates on the future mass loss of the ice sheets using numerical models, basal ice temperature is of paramount importance. In this study, the basal temperature and basal melt rate under the Greenland Ice Sheet are estimated using the Robin temperature solution. The analytical Robin solution is obtained by solving the heat conservation equation for steady state conditions, assuming that advection and diffusion are significant only in the vertical direction. In this study, the sensitivity of the basal temperature obtained from the Robin solution to changes in input parameters, including changes in atmospheric conditions, ice thickness, and geothermal heat flux is tested. Although the Robin solution is frequently used in glaciology, there has been no quantitative study to estimate the effect of neglecting the horizontal advection on basal temperatures in regions of higher velocity. Here, a two-dimensional model is applied to quantify the effect of horizontal heat advection on basal temperatures. Overall, horizontal heat advection lowers the basal temperature except in regions where surface mass balance gradients are negative along the flow. Comparing the results from the 2D temperature model to the Robin solution along multiple flowlines of the Greenland Ice Sheet suggest that the horizontal heat advection alters the basal temperatures by less than 3°C up to 30-45% of the flow distance away from the ice divide; at greater distances this difference increases rapidly. All simulations using the Robin solution predict substantial basal melting under the northeast drainage basin of the ice sheet. Our 2D model results also show that because of the negative surface mass balance gradient, horizontal heat advection increases the basal temperatures in the northeast basin. Our obtained map of basal melting area matches well with the radar detected basal water under the north and northeast drainage basins. However, low basal temperatures estimated at the Camp Century ice core location in the northwest of the ice sheet is in contrast with the radar observations.

  20. High Pressure Melting, Phase Diagrams, and Equations of State in the Fe-FeSi System with Application to Earth's Core

    NASA Astrophysics Data System (ADS)

    Fischer, R. A.; Campbell, A. J.; Reaman, D. M.; Heinz, D. L.; Dera, P. K.; Prakapenka, V.

    2012-12-01

    The Earth's core is comprised mostly of iron, with some nickel and several weight percent of one or more light elements. The light element(s) dictate phase relations, structure, and dynamic behaviour, so it is crucial to evaluate various candidates at conditions of planetary interiors. We present results on high P-T phase diagrams and equations of state in the Fe-FeSi system with application to the structure and composition of Earth's core. X-ray diffraction measurements were performed on stoichiometric FeSi and on Fe-Si alloys containing 9 and 16 wt% silicon in a laser-heated diamond anvil cell at the APS, NSLS, and ALS. Pressures were determined from the lattice parameter of KBr. We have investigated the phase diagram of Fe-9Si to 100 GPa and over 3000 K. Our melting curve agrees with previous results on similar alloys [1,2], as demonstrated using multiple methods of detecting melting. Our subsolidus results are similar to those of Lin et al. [3], though we find the B2 structure instead of bcc, and a shallower slope for the hcp+B2 to fcc+B2 boundary. We studied phase relations of Fe-16Si to over 135 GPa, finding agreement with previous melting curves [2,4]. Below 45 GPa, this alloy has the D0_3 structure. At high pressures, Fe-16Si breaks down into a mixture of B2 and hcp phases, with this mixture stable to pressures of the Earth's outer core. This is the first study on the B2 phase of FeSi with in situ X-ray diffraction at high pressures and temperatures. We report a wide B2+B20 two-phase field in FeSi, with complete conversion to the B2 structure by ~42 GPa. A melting experiment on FeSi agrees with the results of Lord et al. [5]. We have synthesized our results with previous studies to construct T-X and P-X phase diagrams, and we have determined thermal equations of state of each alloy. Our measured densities can be used to constrain the maximum amount of silicon in the Earth's outer core by comparison to the equation of state of hcp-Fe [6] and the seismologically-determined density. Assuming a core-mantle boundary (CMB) temperature of 4000 +/- 500 K and a 1-2% density decrease upon melting, the amount of silicon in the outer core required to match PREM at the CMB is 11.3 +/- 1.5 weight percent, under the simplifying assumption of a purely Fe-Ni-Si outer core. The minimum temperature of an Fe-Si outer core is 4380 K, based on the eutectic melting point of Fe-FeSi alloys, and silicon is shown not to significantly depress the melting point of iron at core conditions. At the highest pressures reached, only the hcp and B2 structures are seen in the Fe-FeSi system. We predict that alloys containing more than ~4-8 wt% Si will convert to an hcp+B2 mixture and later to the hcp structure with increasing pressure, and that an iron-silicon alloy in the Earth's inner core would most likely be a mixture of hcp and B2 phases. [1] Kuwayama and Hirose (2004) Am Mineral 89, 273-276 [2] Morard et al. (2011) PCM 38, 767-776 [3] Lin et al (2002) Science 295, 313-315 [4] Asanuma et al. (2010) PCM 37, 353-359 [5] Lord et al. (2010) JGR 115, B06208 [6] Dewaele et al. (2006) PRL 97, 215504

  1. REVIEWS OF TOPICAL PROBLEMS: Viscosity measurements on metal melts at high pressure and viscosity calculations for the earth's core

    Microsoft Academic Search

    Vladimir N. Mineev; Aleksandr I. Funtikov

    2004-01-01

    A review is given of experimental and calculated data on the viscosity of iron-based melts on the melting curve. The interest in these data originates in the division of opinion on whether viscosity increases rather moderately or considerably in the high-pressure range. This disagreement is especially pronounced in the interpretation of the values of molten iron and its compounds in

  2. Crustal structure and melt supply variability in the presence of oceanic core complex formation: The Mid-Atlantic Ridge at 13°N

    NASA Astrophysics Data System (ADS)

    Mallows, C.; Searle, R. C.

    2009-12-01

    The section of the Mid-Atlantic Ridge (MAR) between the Fifteen Twenty and Marathon Fracture Zones exhibits a diverse morphology. In one instance, the seafloor displays a terrain typical of that which fits a traditional model of robust magmatism and linear abyssal hill formation. However, temporal and spatial variation in melt supply to the ridge creates oceanic detachment terrains, where plate separation is accommodated predominantly on long-lived (~1 Ma) detachment faults. Lower-crustal and upper-mantle rocks are transported to the seafloor, forming oceanic core complexes (OCCs). Although widely studied, little is still known about the precise mechanisms by which OCCs initiate, evolve and subsequently terminate. Numerical models predict that OCC formation occurs at a critical melt supply value. Here, we present the results of a deep-towed geophysical and shipboard gravimetry survey, with the aims of placing constraints on the relationship between OCC formation and melt supply, and also to characterise the regional crustal structure. Our high-resolution, deep-towed sidescan sonar data suggest that OCCs actively form without any adjacent seafloor volcanism, which is in contrast to the modelling work of others which suggests that OCCs must form along with some degree of melting persistent throughout. Older, off-axis core complexes co-exist with extensive evidence for renewed magmatism in the axial valley. In some instances surficial volcanism is observed cutting across detachment surfaces, which may act as the temporal control on OCC formation. Furthermore, sidescan sonar data have been carefully mapped so as to illustrate the fault patterns that occur on the tectonic plate conjugate to that of OCC extension (which is characterised by strain partitioning onto a high amount of small offset faults). Crustal thickness variation derived from sea-level gravity measurements are also used to assess the controls on OCC formation, with the youngest OCCs in the region apparently being formed between discrete, localised zones of robust melt supply.

  3. Special relativity: two postulates or one?

    NASA Astrophysics Data System (ADS)

    Eckhard, David; Panin, Alexander

    2006-10-01

    In current physics textbooks special relativity is derived from Einstein's two postulates: 1.The laws of physics are the same in all inertial frames. 2. The speed of light is the same as measured in all inertial frames. Because the speed of light is also the proportionality constant in the strength of electromagnetic interactions, and is among three fundamental constants (c, h, G) governing laws of physics, then the second postulate is the consequence of the first one (indeed, otherwise Coulomb law and all e/m phenomena would be reference frame dependent). Therefore, should not SR be reduced to one postulate only? Details of this discussion are presented.

  4. Thermodynamics of melting relations in the system Fe-FeO: implications for the oxygen content in the Earth's outer core

    NASA Astrophysics Data System (ADS)

    Komabayashi, T.

    2012-12-01

    Thermodynamics of melting relations in the system Fe-FeO was investigated to the outer core-inner core boundary (ICB) pressure from a self-consistent thermodynamic database for Fe and FeO phases which was evaluated from the latest static high-pressure and -temperature experiments. With the ideal solution model assumed for liquids at the ICB pressure condition, the eutectic temperature is 3680 K, which contradicts the results of the DAC experiments showing a solid assemblage Fe+FeO was stable up to 4200 K. Then, non-ideality of mixing for liquids was assessed to make the eutectic temperature consistent with the experiments. The new solution model predicts that the eutectic composition is about Fe-3.5 wt.%O, almost constant under the core pressures, which compositions would put the limit of the oxygen content in the core because the density of solid FeO is too small to match the inner core density. From the Gibbs free energy for the Fe-FeO liquids, I calculated the density, sound velocity, and adiabatic temperature gradient of a hypothetical oxygen-bearing outer core. Under deep outer core conditions, the addition of oxygen reduces the compressional wave velocity of pure iron liquid, moving it away from seismologically constrained values. An O-rich bulk outer core model is thus exclusive. On the other hand, at the top of the outer core, the addition of oxygen does not significantly change the velocity of iron liquids, which could not explain the low velocity layer with a thickness 60-70 km observed there.

  5. A MELCOR Application to Two Light Water Reactor Nuclear Power Plant Core Melt Scenarios with Assumed Cavity Flooding Action

    Microsoft Academic Search

    Francisco Martin-Fuertes; Juan Manuel Martin-Valdepenas; Jose Mira; Maria Jesus Sanchez

    2003-01-01

    The MELCOR 1.8.4 code Bottom Head package has been applied to simulate two reactor cavity flooding scenarios for when the corium material relocates to the lower-plenum region in postulated severe accidents. The applications were preceded by a review of two main physical models, which highly impacted the results. A model comparison to available bibliography models was done, which allowed some

  6. MELPROG-POW/MOD1: A two-dimensional, mechanistic code for analysis of reactor core melt progression and vessel attack under severe accident conditions

    SciTech Connect

    Dosanjh, S.S. (ed.)

    1989-05-01

    The US Nuclear regulatory Commission has made the development of mechanistic models for severe accident progression a major priority. The purpose of these models is to provide detailed, best-estimate, coupled analyses of all the major phenomena involved in the reactor vessel and coolant system in the course of the accident. To meet this objective, the MELPROG computer code is being developed. This report describes the two-dimensional, pressurized water reactor (PWR) version of the MELPROG computer code, MELPROG/PWR-MOD1. Preliminary BWR work is described in this report. MELPROG is coupled to the TRAC-PF-1 RCS thermal-hydraulics code to provide an integrated analysis of the behavior of core, vessel, and reactor coolant systems during severe accidents. MELPROG treats core degradation and loss of geometry, debris formation, core melting, attack on supporting structures, slumping, melt/water interactions and vessel failure. The key element in MELPROG is the use of detailed modeling for the entire damage progression and failure sequence. Emphasis is also placed on the rates of hydrogen, steam and fission product formation, and transport to containment during the accident.

  7. Overview of Special Relativity Einstein's Two Postulates

    E-print Network

    Hart, Gus

    Overview of Special Relativity Einstein's Two Postulates Relativistic mechanics modify Newton vectors: antisymmetric tensor (4-d) 3 #12;Galilean versus Special Relativity Galilean Relativity Special transformations Relativistic equations for mechanics Principle of relativity: the laws of physics apply in all

  8. Lorentzian quantum reality: postulates and toy models.

    PubMed

    Kent, Adrian

    2015-08-01

    We describe postulates for a novel realist version of relativistic quantum theory or quantum field theory in Minkowski space and other background space-times, and illustrate their application with toy models. PMID:26124245

  9. Lorentzian Quantum Reality: Postulates and Toy Models

    E-print Network

    Adrian Kent

    2014-11-11

    We describe postulates for a novel realist version of relativistic quantum theory or quantum field theory in Minkowski space or other background spacetimes with suitable asymptotic properties. We illustrate their application in toy models.

  10. Petrology of impactites from El'gygytgyn crater: Breccias in ICDP-drill core 1C, glassy impact melt rocks and spherules

    NASA Astrophysics Data System (ADS)

    Wittmann, Axel; Goderis, Steven; Claeys, Philippe; Vanhaecke, Frank; Deutsch, Alexander; Adolph, Leonie

    2013-07-01

    AbstractEl'gygytgyn is a 18 km diameter, 3.6 Ma old impact crater in NE Siberia. International Continental Scientific Drilling Program—El'gygytgyn hole 1C was drilled on the frozen crater lake, 2.3 km from the crater center to a final depth of 517 m below the lake floor. Petrographic and geochemical analyses of 26 drill <span class="hlt">core</span> samples, three impact <span class="hlt">melt</span> rocks from the surface, and seven glass spherules from surface deposits outside the crater are used to characterize the impactite inventory at El'gygytgyn. The bottom 98 m of hole 1C intersected monomict brecciated, unshocked, rhyolitic ignimbrite with minor intercalations of polymict breccia and mafic inclusions. These lithologies are overlain by 89 m of polymict breccia whose components occasionally exhibit scarce, low-degree shock metamorphic features. This unit is succeeded by 10 m of suevite that contains about 1 vol% glassy impact <span class="hlt">melt</span> shards <1 cm in size and a low amount of shock metamorphosed lithic clasts. The suevite is capped by a reworked fallout deposit that constitutes a transition over 4 m into lacustrine sedimentation. A higher abundance of shock metamorphosed lithic clasts, and glass spherules, some with Ni-rich spinel and admixture of an ultramafic component, characterize this unit. We tentatively interpret this impactite section as allochthonous breccia in the vicinity of El'gygytgyn's central ring uplift. The geochemical compositions of seven glass spherules from terrace deposits 2 km outside the crater and eight spherules from the reworked fallout deposit in hole 1C show far greater variability than the composition of impact <span class="hlt">melt</span> shards and impact <span class="hlt">melt</span> rocks. Some of these spherules also show strong enrichments in siderophile elements.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.springerlink.com/index/eytrbbxmd3ev5hqn.pdf"><span id="translatedtitle">Timescales of <span class="hlt">melt</span> generation and the thermal evolution of the Himalayan metamorphic <span class="hlt">core</span>, Everest region, eastern Nepal</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Karen Viskupic; Kip V. Hodges; Samuel A Bowring</p> <p>2005-01-01</p> <p>In the Everest region of the Nepalese Himalaya, 40Ar\\/39Ar and U-Pb geochronology provide evidence for a complex thermal history marked by multiple episodes of granite intrusion. The oldest mobilized <span class="hlt">melt</span> formed syn-deformational granitic sills that have U-Pb crystallization ages of 21.33±0.03 and 21.80±0.05 Ma. Preserved in these same granites is a record of earlier magmatic crystallization of xenotime, zircon and monazite</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/821220"><span id="translatedtitle"><span class="hlt">Melt</span> fracture revisited</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Greenberg, J. M.</p> <p>2003-07-16</p> <p>In a previous paper the author and Demay advanced a model to explain the <span class="hlt">melt</span> fracture instability observed when molten linear polymer <span class="hlt">melts</span> are extruded in a capillary rheometer operating under the controlled condition that the inlet flow rate was held constant. The model <span class="hlt">postulated</span> that the <span class="hlt">melts</span> were a slightly compressible viscous fluid and allowed for slipping of the <span class="hlt">melt</span> at the wall. The novel feature of that model was the use of an empirical switch law which governed the amount of wall slip. The model successfully accounted for the oscillatory behavior of the exit flow rate, typically referred to as the <span class="hlt">melt</span> fracture instability, but did not simultaneously yield the fine scale spatial oscillations in the <span class="hlt">melt</span> typically referred to as shark skin. In this note a new model is advanced which simultaneously explains the <span class="hlt">melt</span> fracture instability and shark skin phenomena. The model <span class="hlt">postulates</span> that the polymer is a slightly compressible linearly viscous fluid but assumes no slip boundary conditions at the capillary wall. In simple shear the shear stress {tau}and strain rate d are assumed to be related by d = F{tau} where F ranges between F{sub 2} and F{sub 1} > F{sub 2}. A strain rate dependent yield function is introduced and this function governs whether F evolves towards F{sub 2} or F{sub 1}. This model accounts for the empirical observation that at high shears polymers align and slide more easily than at low shears and explains both the <span class="hlt">melt</span> fracture and shark skin phenomena.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFM.T11B4546W"><span id="translatedtitle">Nanometer quartz grains and rapid cooling <span class="hlt">melt</span> in fault gouge during earthquake process - observed from the WFSD-1 drilling <span class="hlt">core</span> sample</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, H.; Li, H.; Janssen, C.; Wirth, R.</p> <p>2014-12-01</p> <p>Drilling into active faults is an effective way to get data and materials at depth that help to understand the material properties, physical mechanisms and healing processes of the faults. The Wenchuan earthquake fault scientific drilling project (WFSD) was conducted immediately after the 2008 Wenchuan earthquake (Mw 7.9). The first borehole of the project (WFSD-1) penetrates the Yingxiu-Beichuan fault with a final depth of 1201.15 m and meet the principal slip zone (PSZ) of Wenchuan earthquake at depth of 589.2 m. About 183.3 m-thick fault rocks are recognized in the WFSD-1 drilling <span class="hlt">core</span> from 575.7 to 759 m-depth, which was confirmed as the Yingxiu-Beichuan fault zone with a real thickness of about 100 m due to the borehole inclination of 11°. In this research we got samples from WFSD-1 drilling <span class="hlt">core</span> at the depth of 732.4-732.8 m, in which black gouge, gray gouge, fine-grained fault breccia and coarse-grained fault breccia layers can be distinguished clearly. Slickensides were developed in the surface of the black gouge layer. The protolith of this segment is sandstone. Based on detailed microstructural analysis using electron optical microscope, scanning electron microscope (SEM) and transmission electron microscope (TEM). An about 1 mm-thick amorphous material layer containing small quartz grains was observed. Circles with different densities were observed in the amorphous material indicate a <span class="hlt">melt</span>-origin. Cracks are developed in the amorphous material, which are suggested to be caused by general volume reduction as a result of rapid cooling contraction. TEM-EDX analysis of the amorphous material indicates mainly feldspar composition, implying the <span class="hlt">melting</span> temperature was >1230?, while quartz grains did not <span class="hlt">melt</span> indicating a temperature <1700?. Nano-scale quartz grains were observed in a very small layer showing a different structure at the edge of the amorphous layer, indicating that nano quartz grains were formed by the comminution during earthquake, which is very important in earthquake energy budgets calculation. These microstructural analysis results reveal that the amorphous layer may formed by rapid cooling of the frictional <span class="hlt">melt</span> material caused by high-velocity slip during a large earthquake, and fluid flow may played an important role in the rapid cooling process.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/26454382"><span id="translatedtitle">Low energy nuclear reaction polyplasmon <span class="hlt">postulate</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>John L. Russell</p> <p>2008-01-01</p> <p>An explanation is proposed for the nuclear reactions that occur in the electrolysis class of LENR processes. The proposed explanation <span class="hlt">postulates</span> that a proton, or deuteron, dissolved in the hydrogen bearing metal cathode, absorbs its associated atomic electron to become a short lived state of the neutron with the resulting neutrino in a singular wave function centered on the neutron.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFMMR13B1673X"><span id="translatedtitle">Ringwoodite rim around olivine <span class="hlt">core</span> in shock-induced <span class="hlt">melt</span> veins of Antarctic chondrite : Mechanisms of transformation and Fe-Mg diffusion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xie, Z.; Li, X.; Sharp, T. G.; de Carli, P. S.</p> <p>2009-12-01</p> <p>Introduction: High-pressure minerals, produced by shock metamorphism, are common in and around <span class="hlt">melt</span> veins in highly shocked chondrites. The shock duration can be constrained by using transformation kinetics, such as the crystallization rate of the <span class="hlt">melt</span>-vein matrix[1-2], or growth rate of the high-pressure minerals [3-4], or using elements diffusion rate between two minerals [5]. Using transformation kinetics to constrain shock duration de-pend on the details of the transformation mechanism. For example, growth of topotaxial ringwoodite in olivine with coherent interfaces is slower than growth of inclusions with incoherent interfaces [4-5]. Similarly, diffusion-controlled growth, where rates are determined by long-range diffusion, is generally much slower than interface-controlled growth, which is only dependent on diffusion across the interface [6-8]. The occurrences of the high-pressure mineral rims were recently reported in shock-induced <span class="hlt">melt</span> veins in several heavily shocked (S6) chondrites, ALH78003, Peace River and GRV052049 [9-11]. Here we report EMAP and Raman results of the ringwoodite rims around olivine <span class="hlt">cores</span> in shock veins of the Antarctic chondrites GRV 022321, and to elucidate the mechanisms of transformation and Mg-Fe diffusion of the olivine to ringwoodite. Results: GRV022321 has a network of black veins which enclose abundant host-rock fragments. The enclosed fragments have sizes ranging from 5 µm to 30 µm, with a brighter rim up to several µm wide and a dark <span class="hlt">core</span> in reflected light and BSE image. The Raman data reveal that the rim mineral is ringwoodite signature, and the <span class="hlt">core</span> minerals are dominated by olivine and mixed minor ringwoodite. EMAP data confirm that the ringwoodite in rim is richer in faylite (Fa) than the olivine <span class="hlt">core</span>. The Fa values range from 50 to 10 with the outer rim having highest Fa value, and the inside darker area with a lower value. Discussion: The occurrence of the rounded shape grains with smooth edges embedded in the fine matrix in shock-induced <span class="hlt">melt</span> veins suggest that they are enclosed host-rock fragments and that the ringwoodite in the rim was transformed by solid-state transformation from previous olivine. The variable extent of transformation is likely a result of temperature variations during shock, with the hottest outer olivine forming the ringwoodite rim. The outer hotter ringwoodite attract more Fe than inside cooler olivine, and Mg-Fe diffusion occurs in rapid transformation at high pressure and temperature over up to 10 µm distance. The sample is unique because we can test and double check different shock duration constraints in future work. References: [1] Langenhorst and Poirier (2000) EPSL 184, 37-55. [2] Xie, Z. et al. (2006) GCA, 70. 504-515. [3] Ohtani et al. (2004) EPSL 227(3-4), 505-515. [4] Xie and Sharp (2007), EPLS, 433-445. [5] Beck, et al. (2005) Nature 435, 1071-1074. [6] Kerschhofer et al. (1996) Science 274 (5284), 79-81. [7] Kerschhofer et al. (2000) PEPI 121, 59-76. [8] Sharp and DeCarli (2006) MESS II, 653-677. [9] Ohtani et al. (2006), Shock Waves, 16:45-52. [10] Miyahara et al. (2008) Proceedings. of NAS 105,8542-8547. [11] Feng et al. (2007), MAPS 42, A45.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53484611"><span id="translatedtitle"><span class="hlt">Melting</span> of Fe and Fe120Si8 at the Earth's <span class="hlt">Core</span> Pressures by ab Initio Molecular Dynamics</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>A. B. Belonoshko; A. Rosengren; L. Burakovsky; D. L. Preston; B. Johansson</p> <p>2008-01-01</p> <p>The solid Earth's inner <span class="hlt">core</span> (IC) consists mainly of iron likely alloyed with some light elements. At low temperature iron is stable in hexagonal close packed (hcp) phase up to very high pressures. However, there is an accumulating evidence that under pressures (~ 364 GPa) and temperatures (above 6000 K) in the Earth's IC iron, either pure or alloyed with</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/21529045"><span id="translatedtitle"><span class="hlt">Postulates</span> for measures of genuine multipartite correlations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bennett, Charles H. [IBM T. J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Grudka, Andrzej [Institute of Theoretical Physics and Astrophysics, University of Gdansk, PL-80-952 Gdansk (Poland); Faculty of Physics, Adam Mickiewicz University, PL-61-614 Poznan (Poland); Horodecki, Michal; Horodecki, Ryszard [Institute of Theoretical Physics and Astrophysics, University of Gdansk, PL-80-952 Gdansk (Poland); Horodecki, Pawel [Faculty of Applied Physics and Mathematics, Technical University of Gdansk, PL-80-952 Gdansk (Poland)</p> <p>2011-01-15</p> <p>A lot of research has been done on multipartite correlations, but the problem of satisfactorily defining genuine multipartite correlations--those not trivially reducible to lower partite correlations--remains unsolved. In this paper we propose three reasonable <span class="hlt">postulates</span> which each measure or indicator of genuine multipartite correlations (or genuine multipartite entanglement) should satisfy. We also introduce the concept of degree of correlations, which gives partial characterization of multipartite correlations. Then, we show that covariance does not satisfy two <span class="hlt">postulates</span> and hence it cannot be used as an indicator of genuine multipartite correlations. Finally, we propose a candidate for a measure of genuine multipartite correlations based on the work that can be drawn from a local heat bath by means of a multipartite state.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=USGSPUBS&redirectUrl=http://pubs.er.usgs.gov/publication/70035249"><span id="translatedtitle">Megablocks and <span class="hlt">melt</span> pockets in the Chesapeake Bay impact structure constrained by magnetic field measurements and properties of the Eyreville and Cape Charles <span class="hlt">cores</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Shah, A.K.; Daniels, D.L.; Kontny, A.; Brozena, J.</p> <p>2009-01-01</p> <p>We use magnetic susceptibility and remanent magnetization measurements of the Eyreville and Cape Charles <span class="hlt">cores</span> in combination with new and previously collected magnetic field data in order to constrain structural features within the inner basin of the Chesapeake Bay impact structure. The Eyreville <span class="hlt">core</span> shows the first evidence of several-hundred-meter-thick basement-derived megablocks that have been transported possibly kilometers from their pre-impact location. The magnetic anomaly map of the structure exhibits numerous short-wavelength (<2 km) variations that indicate the presence of magnetic sources within the crater fill. With <span class="hlt">core</span> magnetic properties and seismic reflection and refraction results as constraints, forward models of the magnetic field show that these sources may represent basementderived megablocks that are a few hundred meters thick or <span class="hlt">melt</span> bodies that are a few dozen meters thick. Larger-scale magnetic field properties suggest that these bodies overlie deeper, pre-impact basement contacts between materials with different magnetic properties such as gneiss and schist or gneiss and granite. The distribution of the short-wavelength magnetic anomalies in combination with observations of small-scale (1-2 mGal) gravity field variations suggest that basement-derived megablocks are preferentially distributed on the eastern side of the inner crater, not far from the Eyreville <span class="hlt">core</span>, at depths of around 1-2 km. A scenario where additional basement-derived blocks between 2 and 3 km depth are distributed throughout the inner basin-and are composed of more magnetic materials, such as granite and schist, toward the east over a large-scale magnetic anomaly high and less magnetic materials, such as gneiss, toward the west where the magnetic anomaly is lower-provides a good model fi t to the observed magnetic anomalies in a manner that is consistent with both gravity and seismic-refraction data. ?? 2009 The Geological Society of America.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/21160621"><span id="translatedtitle">Blind Benchmark Calculations for <span class="hlt">Melt</span> Spreading in the ECOSTAR Project</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Spengler, C.; Allelein, H.J. [Gesellschaft fuer Anlagen- und Reaktorsicherheit, Schwertnergasse 1, 50667 Cologne (Germany); Foit, J.J.; Alsmeyer, H. [Forschungszentrum Karlsruhe, P.O. Box 36 40, 76021 Karlsruhe (Germany); Spindler, B.; Veteau, J.M. [CEA, 17, rue des Martyrs, 38054 Grenoble (France); Artnik, J.; Fischer, M. [Framatome ANP, P.O. Box 32 20, 91050 Erlangen (Germany)</p> <p>2004-07-01</p> <p>The Project ECOSTAR (5. EC Framework Programme) on Ex-Vessel <span class="hlt">Core</span> <span class="hlt">Melt</span> Stabilisation Research is oriented towards the analysis and mitigation of severe accident sequences that could occur in the ex-vessel phase of a <span class="hlt">postulated</span> <span class="hlt">core</span> <span class="hlt">melt</span> accident. Spreading of the corium <span class="hlt">melt</span> on the available basement surface is an important process, which defines the initial conditions for concrete attack and for the efficiency of cooling in case of water contact, respectively. The transfer and spreading of the <span class="hlt">melt</span> on the basement is one of the major issues in ECOSTAR. This is addressed here by a spreading code benchmark involving a large-scale spreading experiment that is used for the validation of the existing spreading codes. The corium <span class="hlt">melt</span> is simulated by a mixture of Al{sub 2}O{sub 3}, SiO{sub 2}, CaO and FeO with a sufficiently wide freezing interval. In the 3-dim benchmark test ECOKATS-1 170 litres of oxide <span class="hlt">melt</span> are poured onto a 3 m by 4 m concrete surface with a low flow rate of about 2 l/s. From the results of an additional 2-dim channel experiment some basic rheological data (e.g. initial viscosity) are obtained in order to minimise the uncertainty in material properties of the <span class="hlt">melt</span>. The participating spreading codes CORFLOW (Framatome ANP/FZK), LAVA (GRS), and THEMA (CEA) differ from each other by their focus of modelling and the assumptions made to simplify the relevant transport equations. In a first step both experiments (3-dim/2-dim) are calculated blindly by the participating codes. This serves for an overall assessment of the codes capabilities to predict the spreading of a <span class="hlt">melt</span> with rather unknown material properties. In a second step the 3-dim experiment ECOKATS-1 is recalculated by the codes with the more precise knowledge of the rheological behaviour of the oxide <span class="hlt">melt</span> in the 2-dim experiment. This, in addition, serves for the validation of the codes' capabilities to predict the spreading of a <span class="hlt">melt</span> with well-known material properties. Based on the benchmark results and taking the specific validation process for each of the three codes applied into account, it is recommended that the spreading issue for reactor safety research be considered closed. (authors)</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www-com.physik.hu-berlin.de/~fjeger/Cosmolect1-4.pdf"><span id="translatedtitle">Special Relativity in a Nutshell Basic <span class="hlt">Postulates</span>: Einstein 1905</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Peters, Achim</p> <p></p> <p>COSMOLOGY Special Relativity in a Nutshell Basic <span class="hlt">Postulates</span>: Einstein 1905 All observers moving Lect. 4 R 138 #12;COSMOLOGY Special Relativity in a Nutshell Basic <span class="hlt">Postulates</span>: Einstein 1905 All;COSMOLOGY Special Relativity in a Nutshell Basic <span class="hlt">Postulates</span>: Einstein 1905 All observers moving uniformly</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://web.mnstate.edu/jasperse/Chem355/Melting%20Range.doc.pdf"><span id="translatedtitle"><span class="hlt">Melting</span> Range 3 <span class="hlt">Melting</span> Range</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Jasperse, Craig P.</p> <p></p> <p>. At the chemical level, it is impossible to "raise" the <span class="hlt">melting</span> point of an already pure substance. It's <span class="hlt">melting</span> point can be depressed by contamination, but not raised. Practical: If the <span class="hlt">melting</span> point for an unknown. But if the resulting <span class="hlt">melting</span> point gets higher, the original sample was obviously impure.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1203.4516v2"><span id="translatedtitle">Information-theoretic <span class="hlt">postulates</span> for quantum theory</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Markus P. Mueller; Lluis Masanes</p> <p>2013-04-23</p> <p>Why are the laws of physics formulated in terms of complex Hilbert spaces? Are there natural and consistent modifications of quantum theory that could be tested experimentally? This book chapter gives a self-contained and accessible summary of our paper [New J. Phys. 13, 063001, 2011] addressing these questions, presenting the main ideas, but dropping many technical details. We show that the formalism of quantum theory can be reconstructed from four natural <span class="hlt">postulates</span>, which do not refer to the mathematical formalism, but only to the information-theoretic content of the physical theory. Our starting point is to assume that there exist physical events (such as measurement outcomes) that happen probabilistically, yielding the mathematical framework of "convex state spaces". Then, quantum theory can be reconstructed by assuming that (i) global states are determined by correlations between local measurements, (ii) systems that carry the same amount of information have equivalent state spaces, (iii) reversible time evolution can map every pure state to every other, and (iv) positivity of probabilities is the only restriction on the possible measurements.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1305.3129v1"><span id="translatedtitle">Simple derivation from <span class="hlt">postulates</span> of generalized vacuum Maxwell equations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Chun Wa Wong</p> <p>2013-05-11</p> <p>The two <span class="hlt">postulates</span> of special relativity plus the <span class="hlt">postulates</span> of conserved charges, both electric and magnetic, and a resulting linear system are sufficient for the derivation of the generalized vacuum Maxwell equations with both charges. The derivative admits another set of Maxwell equations for charges that are the opposite-parity partners of the usual electric and magnetic charges. These new charges and their photons are parts of the parallel universe of dark matter.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/24664915"><span id="translatedtitle"><span class="hlt">Melting</span> in super-earths.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Stixrude, Lars</p> <p>2014-04-28</p> <p>We examine the possible extent of <span class="hlt">melting</span> in rock-iron super-earths, focusing on those in the habitable zone. We consider the energetics of accretion and <span class="hlt">core</span> formation, the timescale of cooling and its dependence on viscosity and partial <span class="hlt">melting</span>, thermal regulation via the temperature dependence of viscosity, and the <span class="hlt">melting</span> curves of rock and iron components at the ultra-high pressures characteristic of super-earths. We find that the efficiency of kinetic energy deposition during accretion increases with planetary mass; considering the likely role of giant impacts and <span class="hlt">core</span> formation, we find that super-earths probably complete their accretionary phase in an entirely molten state. Considerations of thermal regulation lead us to propose model temperature profiles of super-earths that are controlled by silicate <span class="hlt">melting</span>. We estimate <span class="hlt">melting</span> curves of iron and rock components up to the extreme pressures characteristic of super-earth interiors based on existing experimental and ab initio results and scaling laws. We construct super-earth thermal models by solving the equations of mass conservation and hydrostatic equilibrium, together with equations of state of rock and iron components. We set the potential temperature at the <span class="hlt">core</span>-mantle boundary and at the surface to the local silicate <span class="hlt">melting</span> temperature. We find that ancient (?4?Gyr) super-earths may be partially molten at the top and bottom of their mantles, and that mantle convection is sufficiently vigorous to sustain dynamo action over the whole range of super-earth masses. PMID:24664915</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.springerlink.com/index/mq1861v48485h3l3.pdf"><span id="translatedtitle"><span class="hlt">Melting</span> relationships in the system Fe-Feo at high pressures: Implications for the composition and formation of the earth's <span class="hlt">core</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Takumi Kato; A. E. Ringwood</p> <p>1989-01-01</p> <p>A reconnaissance investigation has been carried out on <span class="hlt">melting</span> relationships in the system Fe-FeO at pressures up to 25 GPa\\u000a and temperatures up to 2200 C using an MA-8 apparatus. Limited studies were also made of the Co-CoO and Ni-NiO systems. In\\u000a the system FeFeO, the rapid exsolution of FeO from liquids during quenching causes some difficulties in interpretation of</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/0905.4398v1"><span id="translatedtitle">Von Neumann and Luders <span class="hlt">postulates</span> and quantum information theory</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Andrei Khrennikov</p> <p>2009-05-27</p> <p>This note is devoted to some foundational aspects of quantum mechanics (QM) related to quantum information (QI) theory, especially quantum teleportation and ``one way quantum computing.'' We emphasize the role of the projection <span class="hlt">postulate</span> (determining post-measurement states) in QI and the difference between its L\\"uders and von Neumann versions. These projection <span class="hlt">postulates</span> differ crucially in the case of observables with degenerate spectra. Such observables play the fundamental role in operations with entangled states: any measurement on one subsystem is represented by an observable with degenerate spectrum in the Hilbert space of a composite system. If von Neumann was right and L\\"uders was wrong the canonical schemes of quantum teleportation and ``one way quantum computing'' would not work. Surprisingly, we found that, in fact, von Neumann's description of measurements via refinement implies (under natural assumptions) L\\"uders projection <span class="hlt">postulate</span>. It seems that this important observation was missed during last 70 years. This result closed the problem of the proper use of the projection <span class="hlt">postulate</span> in quantum information theory. One can proceed with L\\"uders <span class="hlt">postulate</span> (as people in quantum information really do).</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1999PhRvB..60..141J"><span id="translatedtitle"><span class="hlt">Melting</span> of Pb clusters without free surfaces</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jin, Z. H.; Sheng, H. W.; Lu, K.</p> <p>1999-07-01</p> <p><span class="hlt">Melting</span> behaviors of Pb clusters without free surfaces have been studied using molecular dynamics and the Sutton-Chen (SC) potential. Two Pb clusters (PbN, with N=201 and 249) are selected and each of them has been embedded in the <span class="hlt">core</span> of an Al4033 cubo-octahedron, but with different orientation relationship with Al coatings. For the Pb201 cluster, where a parallel cube-cube relationship exists with the Al lattice, semicoherent interfaces can be formed and the <span class="hlt">core</span> can be superheated up to 750 K, in comparing to the equilibrium <span class="hlt">melting</span> point of 615+/-10 K for bulk Pb predicted using the SC potential. On further elevating the temperature, a simultaneous <span class="hlt">melting</span> of both the Pb <span class="hlt">core</span> and the outer Al coating will occur. For the Pb249 cluster without a parallel orientation relationship with Al, no effective semicoherent interface can be formed, and the <span class="hlt">core</span> premelts at about 500 K without breaking the crystalline structure of Al shells. The <span class="hlt">melting</span> point of the Pb inclusions can be predicted using thermodynamic relations. For different Pb-Al interfaces, two <span class="hlt">melting</span> mechanisms exist: one is the homogeneous <span class="hlt">melting</span> which leads to a <span class="hlt">melting</span> point elevation and the other is the heterogeneous <span class="hlt">melting</span> which can induce a <span class="hlt">melting</span> point depression.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/14825130"><span id="translatedtitle">Climatic signal of ice <span class="hlt">melt</span> features in southern Greenland</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Michael M. Herron; Susan L. Herron; Chester C. Langway</p> <p>1981-01-01</p> <p>The stratigraphie record of <span class="hlt">melt</span> features in intermediate depth polar ice <span class="hlt">cores</span> has provided valuable data on past summer climate1-3. The thermal drilling technique used in previous studies precluded extending this record beyond a few hundred years. Recently, however, a 901-m deep ice <span class="hlt">core</span> was mechanically drilled in southern Greenland. The excellent <span class="hlt">core</span> quality and improved techniques for measuring <span class="hlt">melt</span></p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.michaelbeeson.com/research/papers/ParallelIndependence.pdf"><span id="translatedtitle">The Parallel <span class="hlt">Postulate</span> in Constructive Geometry Michael Beeson</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Beeson, Michael</p> <p></p> <p>logic. We developed an axiomatization ECG (Euclidean Constructive Geometry) whose axioms and proofsThe Parallel <span class="hlt">Postulate</span> in Constructive Geometry Michael Beeson June 29, 2011 Abstract Euclidean reasoning about the results of those constructions. A consideration of the relation of the Euclidean</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=ERIC&redirectUrl=http://eric.ed.gov/?q=special+AND+relativity&pg=6&id=ED141089"><span id="translatedtitle">A Conceptual Derivation of Einstein's <span class="hlt">Postulates</span> of Special Relativity.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Bearden, Thomas E.</p> <p></p> <p>This document presents a discussion and conceptual derivation of Einstein's <span class="hlt">postulates</span> of special relativity. The perceptron approach appears to be a fundamentally new manner of regarding physical phenomena and it is hoped that physicists will interest themselves in the concept. (Author)</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/21650006"><span id="translatedtitle">[Pelletization of <span class="hlt">melts</span> and liquids].</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rabisková, Miloslava</p> <p>2011-04-01</p> <p>During the second half of the last century, pelletization methods based on wetting were developed, e.g. agglomeration in coating pans, pelletization plates or fluid-bed equipment, layering of the drug in solution or suspension on inactive spherical <span class="hlt">cores</span>, extrusion/spheronization and later on also rotoagglomeration in rotogranulators or rotoprocessors. These technologies have become a requisite part of industrial production of solid dosage forms. At present, numerous experimental papers deal with pellet preparation from <span class="hlt">melts</span> and liquids. These new pelletization methods are the topic of the present article. Pellet preparation from <span class="hlt">melts</span> is represented by three methods, i.e. fluid hot <span class="hlt">melt</span> agglomeration, hot <span class="hlt">melt</span> extrusion, and freeze pelletization. Jet cutting and cryopelletization are the techniques dealing with pellet preparation from liquids. PMID:21650006</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1110.1857v2"><span id="translatedtitle">OPERA data and The Equivalence <span class="hlt">Postulate</span> of Quantum Mechanics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Alon E. Faraggi</p> <p>2011-10-24</p> <p>An interpretation of the recent results reported by the OPERA collaboration is that neutrinos propagation in vacuum exceeds the speed of light. It has been further been suggested that this interpretation can be attributed to the variation of the particle speed arising from the Relativistic Quantum Hamilton Jacobi Equation. I show that this is in general not the case. I derive an expression for the quantum correction to the instantaneous relativistic velocity in the framework of the relativistic quantum Hamilton-Jacobi equation, which is derived from the equivalence <span class="hlt">postulate</span> of quantum mechanics. While the quantum correction does indicate deviations from the classical energy--momentum relation, it does not necessarily lead to superluminal speeds. The quantum correction found herein has a non-trivial dependence on the energy and mass of the particle, as well as on distance travelled. I speculate on other possible observational consequences of the equivalence <span class="hlt">postulate</span> approach.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013LPICo1737.3028G"><span id="translatedtitle">Onaping Formation, Ries Suevite and <span class="hlt">Melt</span>-Fuel-Coolant-Interaction (MFCI)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grieve, R. A. F.; Osinski, G. R.; Chanou, A.</p> <p>2013-08-01</p> <p>The Sudbury Onaping Formation and the Ries suevite Ries have been <span class="hlt">postulated</span> to form as the result of <span class="hlt">melt</span>-fuel-coolant-interaction (MFCI), i.e., by the explosive interaction between impact <span class="hlt">melt</span> and water. Both interpretations canot be correct.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/25453077"><span id="translatedtitle">Hidden carbon in Earth's inner <span class="hlt">core</span> revealed by shear softening in dense Fe7C3.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Bin; Li, Zeyu; Zhang, Dongzhou; Liu, Jiachao; Hu, Michael Y; Zhao, Jiyong; Bi, Wenli; Alp, E Ercan; Xiao, Yuming; Chow, Paul; Li, Jie</p> <p>2014-12-16</p> <p>Earth's inner <span class="hlt">core</span> is known to consist of crystalline iron alloyed with a small amount of nickel and lighter elements, but the shear wave (S wave) travels through the inner <span class="hlt">core</span> at about half the speed expected for most iron-rich alloys under relevant pressures. The anomalously low S-wave velocity (vS) has been attributed to the presence of liquid, hence questioning the solidity of the inner <span class="hlt">core</span>. Here we report new experimental data up to <span class="hlt">core</span> pressures on iron carbide Fe7C3, a candidate component of the inner <span class="hlt">core</span>, showing that its sound velocities dropped significantly near the end of a pressure-induced spin-pairing transition, which took place gradually between 10 GPa and 53 GPa. Following the transition, the sound velocities increased with density at an exceptionally low rate. Extrapolating the data to the inner <span class="hlt">core</span> pressure and accounting for the temperature effect, we found that low-spin Fe7C3 can reproduce the observed vS of the inner <span class="hlt">core</span>, thus eliminating the need to invoke partial <span class="hlt">melting</span> or a <span class="hlt">postulated</span> large temperature effect. The model of a carbon-rich inner <span class="hlt">core</span> may be consistent with existing constraints on the Earth's carbon budget and would imply that as much as two thirds of the planet's carbon is hidden in its center sphere. PMID:25453077</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19760003076&hterms=Melting+point&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2528Melting%2Bpoint%2529"><span id="translatedtitle">Skylab M551 metals <span class="hlt">melting</span> experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Poorman, R. M.</p> <p>1975-01-01</p> <p>The objectives of the M551 Metals <span class="hlt">Melting</span> Experiment were to: (1) study behavior of molten metal, (2) characterize metals <span class="hlt">melted</span> and solidified in the low gravity space environment compared to one-gravity of earth, and (3) determine feasibility of joining metals in space. The experiment used the electron beam (EB) and chamber of the M512 apparatus to make a dwell puddle and a <span class="hlt">melt</span> in a rotating disc of varying thickness. Hence, the EB performed cut-through, full and partial penetration <span class="hlt">melts</span>, in addition to a resolidified button. The three disc materials were aluminum 2219-T87, 304 stainless steel, and pure tantalum to provide a wide range of density and <span class="hlt">melting</span> conditions. Observations to date include the proof that EB welding, cutting, and <span class="hlt">melting</span> can be done successfully in low gravity. Earlier, some welding authorities had <span class="hlt">postulated</span> that without gravity the EB would force the molten puddle out of contact. However, the experiment proved that surface tension forces predominate. From the viewpoint of cast-solidification, small, equiaxed grains in Skylab specimens compared to large, elongated grains in ground based specimens were observed. The former are thought to be associated with constitutional supercooling and nucleation where the latter are associated with dendritic solidification. In further support of the more equiaxed grain growth in Skylab, symmetric subgrain patterns were frequently observed where there was much less symmetry in ground based specimens.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1306.6736v1"><span id="translatedtitle">Aharonov--Bohm effect, electrodynamics <span class="hlt">postulates</span>, and Lorentz condition</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>V. B. Bobrov; S. A. Trigger; G. J. F. van Heijst; P. P. J. M. Schram</p> <p>2013-06-28</p> <p>The problem of the relation between the Ahronov-Bohm effect and traditional <span class="hlt">postulates</span> of electrodynamics, which claim that only electric and magnetic fields are observable, is resolved by denial of the statement about validity of the Maxwell equations for microscopic fields. We proceed from the idea that the Maxwell equations, as the generalization of experimental data, are valid only for averaged values. We show that microscopic electrodynamics should be based on <span class="hlt">postulation</span> of the d'Alembert equations for four-vector of the electromagnetic field potential. The Lorentz condition is valid only for the averages and provides the implementation of the Maxwell equations for averages. This concept eliminates the problem of electromagnetic field quantization and provides the correctness of all known results of quantum electrodynamics. Therefore, the "virtuality" of the longitudinal and scalar photons has a formal mathematical character, conditioned by the Maxwell equations for averaged fields. The longitudinal and scalar photons provide not only the Coulomb interaction of charged particles, but also allow the electrical Aharonov-Bohm effect.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60430908"><span id="translatedtitle">Observation of the polymer <span class="hlt">melt</span> flow in injection molding process using co-injection molding technique</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>S. C. Chen; K. F. Hsu; J. S. Huang</p> <p>2009-01-01</p> <p>Studies of the polymer <span class="hlt">melt</span> flow in injection molding process have been carried out by co-injection molding technique using alternating sequence of transparent and colored PMMA resin. Simulations are also developed to predict the <span class="hlt">melt</span> front advancements for both skin and <span class="hlt">core</span> <span class="hlt">melts</span>. Fountain flow effect is evident in all case studies. During the packing process, the polymer <span class="hlt">melt</span> flows</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53385690"><span id="translatedtitle">Yaxcopoil-1 Impact <span class="hlt">Melt</span> Breccias: Silicate <span class="hlt">Melt</span> Clasts Among Dolomite <span class="hlt">Melt</span> and Implications for Deposition</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>M. J. Nelson; H. E. Newsom</p> <p>2006-01-01</p> <p>Microprobe and XRD results suggest Chicxulub Yax-1 <span class="hlt">melt</span> breccia consists of silicate <span class="hlt">melt</span> clasts with K-rich rims amongst quenched dolomite <span class="hlt">melt</span>. A depositional model includes brecciation of silicate <span class="hlt">melt</span> by seawater and infilling by dolomite <span class="hlt">melt</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PMC&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4273394"><span id="translatedtitle">Hidden carbon in Earth’s inner <span class="hlt">core</span> revealed by shear softening in dense Fe7C3</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Li, Zeyu; Zhang, Dongzhou; Liu, Jiachao; Hu, Michael Y.; Zhao, Jiyong; Bi, Wenli; Alp, E. Ercan; Xiao, Yuming; Chow, Paul; Li, Jie</p> <p>2014-01-01</p> <p>Earth’s inner <span class="hlt">core</span> is known to consist of crystalline iron alloyed with a small amount of nickel and lighter elements, but the shear wave (S wave) travels through the inner <span class="hlt">core</span> at about half the speed expected for most iron-rich alloys under relevant pressures. The anomalously low S-wave velocity (vS) has been attributed to the presence of liquid, hence questioning the solidity of the inner <span class="hlt">core</span>. Here we report new experimental data up to <span class="hlt">core</span> pressures on iron carbide Fe7C3, a candidate component of the inner <span class="hlt">core</span>, showing that its sound velocities dropped significantly near the end of a pressure-induced spin-pairing transition, which took place gradually between 10 GPa and 53 GPa. Following the transition, the sound velocities increased with density at an exceptionally low rate. Extrapolating the data to the inner <span class="hlt">core</span> pressure and accounting for the temperature effect, we found that low-spin Fe7C3 can reproduce the observed vS of the inner <span class="hlt">core</span>, thus eliminating the need to invoke partial <span class="hlt">melting</span> or a <span class="hlt">postulated</span> large temperature effect. The model of a carbon-rich inner <span class="hlt">core</span> may be consistent with existing constraints on the Earth's carbon budget and would imply that as much as two thirds of the planet's carbon is hidden in its center sphere. PMID:25453077</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/22039564"><span id="translatedtitle">Reconstruction of intra-bundle fission density profile during a <span class="hlt">postulated</span> LOCA in a CANDU reactor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ilas, D. [Oak Ridge National Laboratory (United States); Rahnema, F. [Georgia Inst. of Technology (United States); Nuclear and Radiological Engineering/Medical Physics Programs, George W. Woodruff School, Georgia Inst. of Technology, Atlanta, GA 30332-0405 (United States); Serghiuta, D. [Canadian Nuclear Safety Commission (Canada); Sarsour, H.; Turinsky, P. J. [North Carolina State Univ. (United States); Stamm'ler, R. [Studsvik Scandpower AS (Norway)</p> <p>2006-07-01</p> <p>In this paper, results related to the reconstruction of intra-bundle fission density profile for a 37-pin CANDU-6 bundle with the highest enthalpy deposition during a <span class="hlt">postulated</span> large LOCA stagnation break in a Bruce B <span class="hlt">core</span> are presented. Bruce B is a nuclear power plant in Kincardine, Ontario (Canada)), on the shores of Lake Huron with 4 CANDU reactors that are rated at about 750 MWe. The reconstruction of the fuel pin fission densities is based on steady-state, three-dimensional simulations with the Monte Carlo code MCNP for a subset of 27 out of 69 time steps during the first two seconds of the power pulse predicted for the fuel bundle at <span class="hlt">core</span> location V13/8. Two-group cross section data libraries are generated for MCNP at each time step by the lattice depletion neutron transport code HELIOS-1.7. To include the effect of the surrounding <span class="hlt">core</span> environment, the calculations are performed with time-dependent albedo boundary conditions inferred from a full <span class="hlt">core</span> simulation of the transient by the nodal diffusion code NESTLE with HELIOS homogenized cross-sections. It is found that the local peaking factor (LPF) in the outer ring varies during the transient, but never exceeds its value before the transient. Inclusion of the <span class="hlt">core</span> environment increases the LPF in the outer ring. For the analyzed case, the increase is 0.72% with a relative error of 0.01% for the LPF before the transient and 0.55% (with a relative error of 0.01%) for the maximum average LPF during the transient. The latter is based on only four selected transient time points. Note that the immediate environment of the 'hot bundle' does not contain any reactivity devices or other perturbing factors. As a result, the increases observed in the LPF in the outer ring may not be representative of the situations in which 'other' <span class="hlt">core</span> environment perturbing factors are present. To determine the effect of these factors on the LPF, further analyses of a bundle in the proximity of control devices should be carried out. (authors)</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2003EJPh...24..301C"><span id="translatedtitle">A dual first-<span class="hlt">postulate</span> basis for special relativity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Coleman, Brian</p> <p>2003-05-01</p> <p>An overlooked straightforward application of velocity reciprocity to a triplet of inertial frames in collinear motion identifies the ratio of their cyclic relative velocities' sum to the negative product as a cosmic invariant - whose inverse square root corresponds to a universal limit speed. A logical indeterminacy of the ratio equation establishes the repeatedly observed unchanged speed of stellar light as one instance of this universal limit speed. This formally renders the second <span class="hlt">postulate</span> redundant. The ratio equation furthermore enables the limit speed to be quantified - in principle - independently of a limit speed signal. Assuming negligible gravitational fields, two deep-space vehicles in non-collinear motion could measure with only a single clock the limit speed against the speed of light - without requiring these speeds to be identical. Moreover, the cosmic invariant (from dynamics, equal to the mass-to-energy ratio) emerges explicitly as a function of signal response time ratios between three collinear vehicles, multiplied by the inverse square of the velocity of whatever arbitrary signal might be used.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.riken.jp/~/media/riken/pr/publications/riken_research/2013/rr201304.pdf"><span id="translatedtitle">RIKENRESEARCH <span class="hlt">Melting</span> point</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Fukai, Tomoki</p> <p></p> <p>RIKENRESEARCH <span class="hlt">Melting</span> point APRIL VOLUME NUMBER #12;©2013RIKEN 900 MHz NMR facility in Yokohama #12 RESEARCH HIGHLIGHTS 6 <span class="hlt">Melting</span> back and forth 7 Silicon's double magic 8 Watching bioactive molecules</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014CRGeo.346..101D"><span id="translatedtitle">F-layer formation in the outer <span class="hlt">core</span> with asymmetric inner <span class="hlt">core</span> growth</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Deguen, Renaud; Olson, Peter; Reynolds, Evan</p> <p>2014-05-01</p> <p>Numerical calculations of thermochemical convection in a rotating, electrically conducting fluid sphere with heterogeneous boundary conditions are used to model effects of asymmetric inner <span class="hlt">core</span> growth. With heterogeneous inner <span class="hlt">core</span> growth but no <span class="hlt">melting</span>, outer <span class="hlt">core</span> flow consists of intense convection where inner <span class="hlt">core</span> buoyancy release is high, weak convection where inner <span class="hlt">core</span> buoyancy release is low, and large scale, mostly westward flow in the form of spiraling gyres. With localized inner <span class="hlt">core</span> <span class="hlt">melting</span>, outer <span class="hlt">core</span> flow includes a gravity current of dense fluid that spreads over the inner <span class="hlt">core</span> boundary, analogous to the seismic F-layer. An analytical model for gravity currents on a sphere connects the structure of the dense layer to the distribution of inner <span class="hlt">core</span> <span class="hlt">melting</span> and solidification. Predictions for F-layer formation by asymmetric inner <span class="hlt">core</span> growth include large-scale asymmetric gyres below the <span class="hlt">core</span>-mantle boundary and eccentricity of the geomagnetic field.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/56755141"><span id="translatedtitle">Pressure <span class="hlt">melting</span> of ice</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Thomas A. Weber; Frank H. Stillinger</p> <p>1984-01-01</p> <p>A 250-molecule ice Ih crystallite has been <span class="hlt">melted</span> at a pressure of about 2 kbars using molecular dynamics computer simulation. The ST2 potential has been used to represent molecular interactions. <span class="hlt">Melting</span> was observed to begin at the crystallite surface and to proceed inward until the entire crystal was converted to an amorphous droplet. The <span class="hlt">melting</span> point was found to be</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19850024765&hterms=earth+core&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dearth%2Bcore"><span id="translatedtitle">A model for <span class="hlt">core</span> formation in the early Earth</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jones, J. H.; Drake, M. J.</p> <p>1985-01-01</p> <p>Two basic types exogenous models were proposed to account for siderophile and chalcophile element abundances in the Earth's upper mantle. The first model requires that the Earth be depleted in volatiles and that, after a <span class="hlt">core</span> formation event which extracted the most siderophile elements into the <span class="hlt">core</span>, additional noble siderophile elements (Pt, Ir, Au) were added as a late veneer and mixed into the mantle. The second model <span class="hlt">postulates</span> a reduced Earth with approximately CI elemental abundances in which a primary <span class="hlt">core</span> forming event depleted all siderophile elements in the mantle. The plausibility of models which require fine scale mixing of chondritic material into the upper mantle is analyzed. Mixing in liquids is more efficient, but large degrees of silicate partial <span class="hlt">melting</span> will facilitate the separation of magma from residual solids. Any external events affecting the upper mantle of the Earth should also be evident in the Moon; but siderophile and chalcophile element abundance patterns inferred for the mantles of the Earth and Moon differ. There appear to be significant physical difficulties associated with chondritic veneer models.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2002iaf..confE.255H"><span id="translatedtitle">Economic Analysis of a <span class="hlt">Postulated</span> space Tourism Transportation System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hill, Allan S.</p> <p>2002-01-01</p> <p>Design concepts and associated costs were defined for a family of launch vehicles supporting a space tourism endeavor requiring the weekly transport of space tourists to and from an Earth- orbiting facility. The stated business goal for the Space Tourist Transportation System (STTS) element of the proposed commercial space venture was to transport and return ~50 passengers a week to LEO at a cost of roughly 50 K per seat commencing in 2005. This paper summarizes the economic analyses conducted within a broader Systems Engineering study of the <span class="hlt">postulated</span> concept. Parametric costs were derived using TransCostSystems' (TCS) Cost Engineering Handbook, version 7. Costs were developed as a function of critical system characteristics and selected business scenarios. Various economic strategies directed toward achieving a cost of ~50 K per seat were identified and examined. The study indicated that with a `nominal' business scenario, the initial cost for developing and producing a fully reusable, 2-stage STTS element for a baseline of 46-passengers was about 15.5 B assuming a plausible `commercialization factor' of 0.333. The associated per-seat ticket cost was ~890 K, more than an order of magnitude higher than desired. If the system is enlarged to 104 passengers for better efficiency, the STTS initial cost for the nominal business scenario is increased to about 19.8 B and the per-seat ticket cost is reduced to ~530 K. It was concluded that achieving the desired ticket cost of 50 K per seat is not feasible unless the size of the STTS, and therefore of the entire system, is substantially increased. However, for the specified operational characteristics, it was shown that a system capacity of thousands of passengers per week is required. This implies an extremely high total system development cost, which is not very realistic as a commercial venture, especially in the proposed time frame. These results suggested that ambitious commercial space ventures may have to rely on sizeable government subsidies for economic viability. For example, in this study a hypothesized government subsidy of half the STTS development cost reduced the per-seat ticket cost by about 35%. A number of other business scenarios were also investigated, including `expensing' the entire program initial cost. These analyses showed that even greater government participation, additional aggressive business strategies and/or very low commercialization factors (in the range of 1/9 to 1/30) must be implemented or attained to achieve the desired per-seat cost of 50 K per passenger with reasonably sized vehicles.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/17763046"><span id="translatedtitle"><span class="hlt">Postulated</span> carbon tetrachloride mode of action: a review.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Manibusan, Mary K; Odin, Marc; Eastmond, David A</p> <p>2007-01-01</p> <p>Under the 2005 U.S. EPA Guidelines for Carcinogen Risk Assessment (1), evaluations of carcinogens rely on mode of action data to better inform dose response assessments. A reassessment of carbon tetrachloride, a model hepatotoxicant and carcinogen, provides an opportunity to incorporate into the assessment biologically relevant mode of action data on its carcinogenesis. Mechanistic studies provide evidence that metabolism of carbon tetrachloride via CYP2E1 to highly reactive free radical metabolites plays a critical role in the <span class="hlt">postulated</span> mode of action. The primary metabolites, trichloromethyl and trichloromethyl peroxy free radicals, are highly reactive and are capable of covalently binding locally to cellular macromolecules, with preference for fatty acids from membrane phospholipids. The free radicals initiate lipid peroxidation by attacking polyunsaturated fatty acids in membranes, setting off a free radical chain reaction sequence. Lipid peroxidation is known to cause membrane disruption, resulting in the loss of membrane integrity and leakage of microsomal enzymes. By-products of lipid peroxidation include reactive aldehydes that can form protein and DNA adducts and may contribute to hepatotoxicity and carcinogenicity, respectively. Natural antioxidants, including glutathione, are capable of quenching the lipid peroxidation reaction. When glutathione and other antioxidants are depleted, however, opportunities for lipid peroxidation are enhanced. Weakened cellular membranes allow sufficient leakage of calcium into the cytosol to disrupt intracellular calcium homeostasis. High calcium levels in the cytosol activate calcium-dependent proteases and phospholipases that further increase the breakdown of the membranes. Similarly, the increase in intracellular calcium can activate endonucleases that can cause chromosomal damage and also contribute to cell death. Sustained cell regeneration and proliferation following cell death may increase the likelihood of unrepaired spontaneous, lipid peroxidation- or endonuclease-derived mutations that can lead to cancer. Based on this body of scientific evidence, doses that do not cause sustained cytotoxicity and regenerative cell proliferation would subsequently be protective of liver tumors if this is the primary mode of action. To fulfill the mode of action framework, additional research may be necessary to determine alternative mode(s) of action for liver tumors formed via carbon tetrachloride exposure. PMID:17763046</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.geol.umd.edu/~ajc/Papers/CampbellPEPI2007preprint.pdf"><span id="translatedtitle">Partial <span class="hlt">Melting</span> in the Iron-Sulfur System at High1 Pressure: A Synchrotron X-ray Diffraction Study2</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Campbell, Andrew</p> <p></p> <p>bound was established at 80 GPa. The28 accuracy of the <span class="hlt">melting</span> point measured in these studies52 <span class="hlt">melting</span> point depression at the pressure of the inner <span class="hlt">core</span> / outer <span class="hlt">core</span> boundary (13653 GPa1 Partial <span class="hlt">Melting</span> in the Iron-Sulfur System at High1 Pressure: A Synchrotron X-ray Diffraction</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2012AGUFMMR11B2476L"><span id="translatedtitle"><span class="hlt">Melting</span> in the Fe-Ni system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lord, O. T.; Walter, M. J.; Vocadlo, L.; Wood, I. G.; Dobson, D. P.</p> <p>2012-12-01</p> <p>The <span class="hlt">melting</span> temperature of the Fe-rich <span class="hlt">core</span> alloy at the inner <span class="hlt">core</span> boundary (ICB) condition of 330 GPa is a key geophysical parameter because it represents an anchor point on the geotherm. An accurate knowledge of the <span class="hlt">melting</span> curves of candidate alloys is therefore highly desirable. In spite of this, there is still considerable uncertainty in the <span class="hlt">melting</span> point even of pure Fe at these conditions; estimates range from as low as 4850K based on one laser heated diamond anvil cell (LHDAC) study [1] to as high as 6900K based on recent quantum Monte Carlo calculations [2]. In reality we expect that the bulk <span class="hlt">core</span> alloy may contain 5-10 wt% Ni (based on cosmochemical and meteoritic arguments) and up to 10 wt% of an as yet undetermined mix of light elements (with Si, S, C and O being the most likely candidates). While some recent studies have looked at the effects of light elements on the <span class="hlt">melting</span> curve of Fe [e.g.: 3,4] with some of these studies including a small amount of Ni in their starting material, to date there has been no systematic study of <span class="hlt">melting</span> temperatures in the Fe-Ni system. To address this issue, we have embarked upon just such a study. Using the LHDAC we have determined the <span class="hlt">melting</span> curve of the pure Ni end-member to 180 GPa, and that of pure Fe to 50 GPa, using perturbations in the power vs. temperature function as the <span class="hlt">melting</span> criterion [5]. Ar or NaCl were employed as pressure media while temperature was measured using standard spectroradiometric techniques [6]. In the case of Ni, perturbations were observed for both the sample and the Ar medium, allowing us to determine the <span class="hlt">melting</span> curve of Ar and Ni simultaneously. Our results thus far for Ni and Ar agree closely with all of the available data, while extending the <span class="hlt">melting</span> curves by a factor of two in pressure. In the case of Fe, our current dataset is also in good agreement with previous studies [2,7]. The agreement of all three <span class="hlt">melting</span> curves with the literature data as well as other materials previously tested [see 5] gives us confidence in the accuracy of our techniques. In the case of Ni, we observe no change in slope, strongly suggesting that Ni remains in the fcc structure to inner <span class="hlt">core</span> conditions, as opposed to Fe, which converts to the hcp structure at 60-100 GPa. Below this pressure, the Fe and Ni <span class="hlt">melting</span> curves are nearly indistinguishable, but above it the Fe <span class="hlt">melting</span> curve becomes much steeper, such that by 330 GPa, the difference between the two is 1500-3600K depending on which iron <span class="hlt">melting</span> curve is chosen from the literature [1,2]. The addition of Ni to Fe expands the fcc field and pushes the fcc-hcp-liquid triple point to higher pressures [e.g.: 8] delaying the point at which the <span class="hlt">melting</span> curve begins to steepen, which could lead to a significant <span class="hlt">melting</span> point depression at the ICB. We hope to present additional data at the meeting to test this hypothesis, including further data on pure Fe, as well as one or more intermediate alloy compositions (up to 200 GPa). [1] Boehler, R. (1993). Nature 363, 534-536 [2] Alfè, D. & Sola, E. (2009). PRL 103, 078501 [3] Morard, G. et al. (2011). PCM 38, 767-776. [4] Asanuma, H. et al. (2010). PCM 37, 353-359. [5] Lord, O. T. et al. (2010). JGR 115, B06208. [6] Walter, M. J. & Koga, K. T. (2004). PEPI. 143-144, 541-558. [7] Shen, G. et al. (1998). GRL 25, 373-376. [8] Kuwayama, Y. et al. (2008). EPSL, 273, 379-385.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.utdallas.edu/~son051000/chem3322/postulates.pdf"><span id="translatedtitle">The <span class="hlt">Postulates</span> of Quantum Mechanics (from Quantum Mechanics by Claude Cohen-Tannoudji, Bernard Diu, and</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Nielsen, Steven O.</p> <p></p> <p>The <span class="hlt">Postulates</span> of Quantum Mechanics (from Quantum Mechanics by Claude Cohen-Tannoudji, Bernard Diu, and Franck Lalo¨e) Introduction The <span class="hlt">postulates</span> of quantum mechanics are the theory. Their physical content to the following questions: (i) How is the state of a quantum mechanical system at a given time described</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.math.ust.hk/~makchen/Math3425/Chap6part2.pdf"><span id="translatedtitle">6.2. Pure death processes 6.2.1. <span class="hlt">Postulates</span> of pure death processes.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Chen, Kani</p> <p></p> <p>45 6.2. Pure death processes 6.2.1. <span class="hlt">Postulates</span> of pure death processes. {X(t) : t [0, )} is called a pure death process with parameters µ0 = 0, µ1, ..., µN , and state space {0, 1, ..., N are equivalent, but <span class="hlt">Postulate</span> 2 is incomplete and cannot be considered as a definition for pure death process. 6</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53487357"><span id="translatedtitle">Seismic velocity decrement ratios for regions of partial <span class="hlt">melt</span> in the lower mantle</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>James G. Berryman</p> <p>2000-01-01</p> <p>For regions of partial <span class="hlt">melt</span> in the lower mantle, both compressional and shear wave velocities decrease monotonically with increasing <span class="hlt">melt</span> volume fraction. Those regions close to the <span class="hlt">core</span>-mantle boundary thought to contain partial <span class="hlt">melt</span> have a velocity decrement ratio (relative change in shear velocity over relative change of compressional velocity) of about 3. Arguments based on effective medium theories have</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.gps.caltech.edu/~jackson/pdf/Jackson_etal2013_EPSL.pdf"><span id="translatedtitle"><span class="hlt">Melting</span> of compressed iron by monitoring atomic dynamics Jennifer M. Jackson a,e,n</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Jackson, Jennifer M.</p> <p></p> <p>compression measurement and considering thermal pressure, we find the <span class="hlt">melting</span> point of iron to be TM ¼30257115 K at P¼8275 GPa. When compared with previously reported <span class="hlt">melting</span> points for iron using static). More specifically, the <span class="hlt">melting</span> point of iron at the boundary between the liquid outer <span class="hlt">core</span> and solid</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015JESS..tmp...53A"><span id="translatedtitle">First-order theory for Earth's inner-<span class="hlt">core</span> anisotropy due to super-rotation and Ramachandran interaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arulsamy, Andrew Das</p> <p>2015-06-01</p> <p>Solidification mechanism at the Lehmann (inner <span class="hlt">core</span>) boundary are <span class="hlt">postulated</span> on the basis of Ramachandran interaction by taking the fluctuating inner <span class="hlt">core</span> super-rotation into account. The <span class="hlt">postulates</span> are found to be consistent with compressional or P-wave velocity obtained from seismic data analysis. We justify these <span class="hlt">postulates</span> to be physically sound and precise, and show that the fluctuating inner <span class="hlt">core</span> super-rotation causes significant changes to the strength of Fe-Fe Ramachandran interaction, which then leads to the observed asymmetric and anisotropic inner <span class="hlt">core</span>. Our <span class="hlt">postulates</span> also reliably explain that the depth-dependent anisotropic P-wave attenuation close to inner <span class="hlt">core</span> surface (to about 100 km deep) is due to phonon excitation probability and different atomic orientation. We also discuss the consistency of our <span class="hlt">postulates</span> with respect to asymmetric inner <span class="hlt">core</span> anisotropy (between western and eastern inner <span class="hlt">core</span> hemispheres).</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/10185682"><span id="translatedtitle">The rock <span class="hlt">melting</span> approach to drilling</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cort, G.E.; Goff, S.J.; Rowley, J.C.; Neudecker, J.W. Jr.; Dreesen, D.S.; Winchester, W.</p> <p>1993-09-01</p> <p>During the early and mid-1970`s the Los Alamos National Laboratory demonstrated practical applications of drilling and <span class="hlt">coring</span> using an electrically-heated graphite, tungsten, or molybdenum penetrator that <span class="hlt">melts</span> a hole as it is slowly pushed through the rock or soil. The molten material consolidates into a rugged glass lining that prevents hole collapse; minimizes the potential for cross-flow, lost circulation, or the release of hazardous materials without casing operations; and produces no cuttings in porous or low density (<1.7 g/cc) formations. Because there are no drilling fluids required, the rock <span class="hlt">melting</span> approach reduces waste handling, treatment and disposal. Drilling by rock <span class="hlt">melting</span> has been demonstrated to depths up to 30 m in caliche, clay, alluvium, cobbles, sand, basalt, granite, and other materials. Penetrating large cobbles without debris removal was achieved by thermal stress fracturing and lateral extrusion of portions of the rock <span class="hlt">melt</span> into the resulting cracks. Both horizontal and vertical holes in a variety of diameters were drilled in these materials using modular, self-contained field units that operate in remote areas. Because the penetrator does not need to rotate, steering by several simple approaches is considered quite feasible. <span class="hlt">Melting</span> is ideal for obtaining <span class="hlt">core</span> samples in alluvium and other poorly consolidated soils since the formed-in-place glass liner stabilizes the hole, encapsulates volatile or hazardous material, and recovers an undisturbed <span class="hlt">core</span>. Because of the relatively low thermal conductivity of rock and soil materials, the heat-affected zone beyond the <span class="hlt">melt</span> layer is very small, <1 inch thick. Los Alamos has begun to update the technology and this paper will report on the current status of applications and designs for improved drills.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015EGUGA..1712702W"><span id="translatedtitle"><span class="hlt">Melt</span> emplacement induced stresses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wallner, Herbert; Schmeling, Harro</p> <p>2015-04-01</p> <p>Transport of <span class="hlt">melt</span> into and through the lithosphere has an essential influence on it's state, evolution and properties. Rock deformation, physically seen as viscous flow, acts on a long time scale compared with the rapid ascent of <span class="hlt">melt</span> originating in the asthenosphere. In our numerical models the short time scale transfer of <span class="hlt">melt</span> is replaced by <span class="hlt">melt</span> extraction and emplacement at a given depth zone above the source region. New findings reveal probably consequential stresses in the high viscous lithosphere. Thermo-mechanical physics of visco-plastic flow is approximated by Finite Difference Method with markers in an Eulerian formulation in two dimensions. The equations of conservation of mass, momentum and energy are solved for a multi component and two phase system: fluid and matrix. The full compaction formulation is used. The high Prandtl number approximation is applied, elasticity is neglected, and rheology is temperature-, stress- and depth-dependent. In consideration of depletion and enrichment <span class="hlt">melting</span> and solidification are controlled by a simplified linear binary solid solution model. Extraction and emplacement of <span class="hlt">melt</span> is accounted for. A continental rift scenario serves to define a model comprising asthenosphere and lithosphere under extensional conditions. A temperature anomaly generates deep <span class="hlt">melt</span> intruding the lithosphere on its way up. We focus on the early phase of <span class="hlt">melting</span>, forming a first plume and releasing some <span class="hlt">melt</span>. Above a fraction limit <span class="hlt">melt</span> extraction induces underpressure at its origin region attracting ambient <span class="hlt">melt</span> and contracting the matrix. A <span class="hlt">melt</span> fraction minimum develops in the inital batch. In the emplacement zone above sudden dilatation, immediate freezing, increase of enrichment and heating takes place. The dilatation of the rock matrix generates relative high stresses if it's viscosity is high. The behaviour is not intuitively comprehensible. Results are compared with numerical solutions of Compaction Boussinesq Approximation.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014LPICo1800.5374H"><span id="translatedtitle"><span class="hlt">Melting</span> of Cosmic Spherules</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huber, M. S.; Goderis, S.; Debaille, V.; Claeys, P.</p> <p>2014-09-01</p> <p>Critical steps in the physical processes occurring during micrometeorite <span class="hlt">melting</span>, based on observations of CT scans of numerous cosmic spherules and micrometeorites, will be presented with supporting visualizations.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.springerlink.com/index/lc4p1jj9e07y270y.pdf"><span id="translatedtitle">Constrained inversion of rheological data to molecular weight distribution for polymer <span class="hlt">melts</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Franco Cocchini; Maria Rossella Nobile</p> <p>2003-01-01</p> <p>In this paper an inverse method for converting linear viscoelastic properties of polymer <span class="hlt">melts</span> into molecular weight distribution (MWD) is presented. It relies on the use of the double reptation mixing rule and the Generalized Exponential function (GEX) describing the MWD; i.e. an a priori knowledge of the nature of the solution is <span class="hlt">postulated</span> following previous attempts (Nobile et al.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/26638728"><span id="translatedtitle">Ash <span class="hlt">melting</span> treatment by rotating type surface <span class="hlt">melting</span> furnace</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Sei-ichi Abe; Fumiaki Kambayashi; Masaharu Okada</p> <p>1996-01-01</p> <p>Results of <span class="hlt">melting</span> treatment of fly ash from municipal solid waste incinerators are described, and safety and an effective use of slag discharged from the <span class="hlt">melting</span> treatment are studied. The fly ash has an average particle size of 22 ?m and a <span class="hlt">melting</span> fluidity point of 1280–1330°C and was able to be <span class="hlt">melted</span> by using a Kubota <span class="hlt">melting</span> furnace without</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/cond-mat/0004011v1"><span id="translatedtitle"><span class="hlt">Melting</span> as a String-Mediated Phase Transition</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Leonid Burakovsky; Dean L. Preston; Richard R. Silbar</p> <p>2000-04-03</p> <p>We present a theory of the <span class="hlt">melting</span> of elemental solids as a dislocation-mediated phase transition. We model dislocations near <span class="hlt">melt</span> as non-interacting closed strings on a lattice. In this framework we derive simple expressions for the <span class="hlt">melting</span> temperature and latent heat of fusion that depend on the dislocation density at <span class="hlt">melt</span>. We use experimental data for more than half the elements in the Periodic Table to determine the dislocation density from both relations. <span class="hlt">Melting</span> temperatures yield a dislocation density of (0.61\\pm 0.20) b^{-2}, in good agreement with the density obtained from latent heats, (0.66\\pm 0.11) b^{-2}, where b is the length of the smallest perfect-dislocation Burgers vector. <span class="hlt">Melting</span> corresponds to the situation where, on average, half of the atoms are within a dislocation <span class="hlt">core</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53260750"><span id="translatedtitle">Chemical Potential Enhanced Mass Transport as Mechanism for Initial <span class="hlt">Melt</span> Migration in Metapelites</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>A. W. Wohlers; L. B. Baumgartner; C. H. Hauzenberger</p> <p>2003-01-01</p> <p>Experimental studies of <span class="hlt">melt</span> segregation models for volatile phase-absent <span class="hlt">melting</span> concluded that deformation and volume change due to hydrate breakdown are the driving force for <span class="hlt">melt</span> migration. Volume increases can lead to micro crack formation, and additional deformation facilitates <span class="hlt">melt</span> extraction. We performed cold-seal experiments on fine-grained (10--100 mum) high-grade contact meta-pelite <span class="hlt">cores</span> (3mm diameter; andalusite-cordierite-biotite zone) at P =</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.earth.ox.ac.uk/__data/assets/pdf_file/0004/20857/AH2.pdf"><span id="translatedtitle">Project EARTH-13-AH2: Planetary <span class="hlt">core</span> formation new isotopic constraints Supervisors: Alex Halliday, Kathrin Abraham, Jane Barling, Pierre Bonnand,</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>the mechanisms of <span class="hlt">core</span> growth are under constrained with models varying between <span class="hlt">melt</span> percolation, diapirism degrees of tendency to enter the <span class="hlt">core</span>, including vanadium, chromium, nickel, germanium, molybdenum</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.cvm.uiuc.edu/~r-hess/manuscp/z00CrismanToxSci.pdf"><span id="translatedtitle"><span class="hlt">Postulated</span> Human Sperm Count Decline May Involve Historic Elimination of Juvenile Iodine Deficiency: A New Hypothesis</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Hess, Rex A.</p> <p></p> <p><span class="hlt">Postulated</span> Human Sperm Count Decline May Involve Historic Elimination of Juvenile Iodine Deficiency deficiency. In a one-generation rat reproduction study, dams were fed an iodine sufficient (control, 200 ppb I) or deficient (low iodine diet [LID],</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1994CoMP..118..157W"><span id="translatedtitle">Compressibility of titanosilicate <span class="hlt">melts</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Webb, Sharon L.; Dingwell, Donald B.</p> <p>1994-06-01</p> <p>The effect of composition on the relaxed adiabatic bulk modulus (K0) of a range of alkali- and alkaline earth-titanosilicate [X{2/n/n+}TiSiO5 (X=Li, Na, K, Rb, Cs, Ca, Sr, Ba)] <span class="hlt">melts</span> has been investigated. The relaxed bulk moduli of these <span class="hlt">melts</span> have been measured using ultrasonic interferometric methods at frequencies of 3, 5 and 7 MHz in the temperature range of 950 to 1600°C (0.02 Pa s < ?s < 5 Pa s). The bulk moduli of these <span class="hlt">melts</span> decrease with increasing cation size from Li to Cs and Ca to Ba, and with increasing temperature. The bulk moduli of the Li-, Na-, Ca- and Ba-bearing metasilicate <span class="hlt">melts</span> decrease with the addition of both TiO2 and SiO2 whereas those of the K-, Rb- and Cs-bearing <span class="hlt">melts</span> increase. Linear fits to the bulk modulus versus volume fraction of TiO2 do not converge to a common compressibility of the TiO2 component, indicating that the structural role of TiO2 in these <span class="hlt">melts</span> is dependent on the identity of the cation. This proposition is supported by a number of other property data for these and related <span class="hlt">melt</span> compositions including heat capacity and density, as well as structural inferences from X-ray absorption spectroscopy (XANES). The compositional dependence of the compressibility of the TiO2 component in these <span class="hlt">melts</span> explains the difficulty incurred in previous attempts to incorporate TiO2 in calculation schemes for <span class="hlt">melt</span> compressibility. The empirical relationship K?V-4/3 for isostructural materials has been used to evaluate the compressibility-related structural changes occurring in these <span class="hlt">melts</span>. The alkali metasilicate and disilicate <span class="hlt">melts</span> are isostructural, independent of the cation. The addition of Ti to the metasilicate composition (i.e. X2TiSiO5), however, results in a series of <span class="hlt">melts</span> which are not isostructural. The alkaline-earth metasilicate and disilicate compositions are not isostructural, but the addition of Ti to the metasilicate compositions (i.e. XTiSiO5) would appear, on the basis of modulus-volume systematics, to result in the <span class="hlt">melts</span> becoming isostructural with respect to compressibility.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/10102825"><span id="translatedtitle">MACCS usage at Rocky Flats Plant for consequence analysis of <span class="hlt">postulated</span> accidents</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Foppe, T.L.; Peterson, V.L.</p> <p>1993-10-01</p> <p>The MELCOR Accident Consequence Code System (MACCS) has been applied to the radiological consequence assessment of potential accidents from a non-reactor nuclear facility. MACCS has been used in a variety of applications to evaluate radiological dose and health effects to the public from <span class="hlt">postulated</span> plutonium releases and from <span class="hlt">postulated</span> criticalities. These applications were conducted to support deterministic and probabilistic accident analyses for safety analyses for safety analysis reports, radiological sabotage studies, and other regulatory requests.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://plantpathology.uark.edu/PlantDiseasePaper.pdf"><span id="translatedtitle">A Computer Program to Improve the Efficiency and Accuracy of <span class="hlt">Postulating</span> Race-Specific Resistance Genes</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Yeshi A. Wamishe; Kevin C. Thompson; Eugene A. Milus</p> <p>2004-01-01</p> <p>Wamishe, Y. A., Thompson, K. C., and Milus, E. A. 2004. A computer program to improve the efficiency and accuracy of <span class="hlt">postulating</span> race-specific resistance genes. Plant Dis. 88:545-549. Gene <span class="hlt">postulation</span> has been the most widely used technique to determine the presence of particu- lar rust resistance genes in lines of small grains. It applies the principles of gene-for-gene speci- ficity</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://oaktrust.library.tamu.edu//handle/1969.1/ETD-TAMU-1975-THESIS-W732"><span id="translatedtitle">Analysis of population radiation dose from a <span class="hlt">postulated</span> nuclear power plant complex </span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Williford, John Michael</p> <p>1975-01-01</p> <p>ANALYSIS OF POPULATION RADIATION DOSE FROM A <span class="hlt">POSTULATED</span> NUCLEAR POWER PLANT COMPLEX A Thesis by JOHN MICHAEL WILLIFORD Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1975 Majoi Subject: Nuclear Engineering/Health Physics ANALYSIS OF POPULATION RADIATION DOSE FROM A <span class="hlt">POSTULATED</span> NUCLEAR POWER PLANT COMPLEX A Thesis by JOHN MICHAEL WILLIFORD Approved as to style and ntent by: Dr. R. D...</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/10104198"><span id="translatedtitle">Dislocation theory of <span class="hlt">melting</span> for iron, revisited</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Poirier, J.P. [Inst., de Physique du Globe de Paris (France); Shankland, T.J. [Los Alamos National Lab., NM (United States)</p> <p>1993-11-01</p> <p><span class="hlt">Melting</span> point T{sub m} of iron at conditions of the Earth`s inner <span class="hlt">core</span> boundary (ICB) has been calculated from dislocation theory of <span class="hlt">melting</span> in metals. Monte Carlo calculations were used to estimate uncertainties introduced by uncertainty in the geophysical parameters that are used in the calculations. These calculations take into account the effects of pressure at ICB conditions and of possible freezing point depression resulting from dilution of pure iron in the outer <span class="hlt">core</span>. With this approach T{sub m} of pure {var_epsilon}-Fe at a pressure of 330 GPa and without freezing point depression is 6160 {plus_minus} 250 K; for a 1000 K freezing point depression it is 6110 K. T{sub m} of pure {gamma}-Fe is 6060 K, a value that is not significantly different. A possible {alpha}{prime} phase would <span class="hlt">melt</span> at 5600 K. These values agree with calculated shock wave determinations of T{sub m}. Although calculated T{sub m} of the pure phase is little affected by assumptions about the extent of freezing point depression, the estimated temperature of the inner <span class="hlt">core</span> boundary is lower by the breezing point depression, perhaps 500--1000 K less than T{sub m} of a pure phase.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/55507899"><span id="translatedtitle">Elasticity of Polydimethylsiloxane <span class="hlt">Melts</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>N. J. Mills</p> <p>1968-01-01</p> <p>THE observation of Mieras and Van Rijn1 that the steady shear flow compliance of polymer <span class="hlt">melts</span> is dependent only on the width of the molecular weight distribution, characterized by Mmacr z\\/Mmacr w, is in accord with our similar measurements on polydimethylsiloxane <span class="hlt">melts</span>. The shear stress p12 and first normal stress difference p11-p22 were measured with a Weissenberg cone and plate</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6213539"><span id="translatedtitle">Development of a fuel-rod simulator and small-diameter thermocouples for high-temperature, high-heat-flux tests in the Gas-Cooled Fast Reactor <span class="hlt">Core</span> Flow Test Loop</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>McCulloch, R.W.; MacPherson, R.E.</p> <p>1983-03-01</p> <p>The <span class="hlt">Core</span> Flow Test Loop was constructed to perform many of the safety, <span class="hlt">core</span> design, and mechanical interaction tests in support of the Gas-Cooled Fast Reactor (GCFR) using electrically heated fuel rod simulators (FRSs). Operation includes many off-normal or <span class="hlt">postulated</span> accident sequences including transient, high-power, and high-temperature operation. The FRS was developed to survive: (1) hundreds of hours of operation at 200 W/cm/sup 2/, 1000/sup 0/C cladding temperature, and (2) 40 h at 40 W/cm/sup 2/, 1200/sup 0/C cladding temperature. Six 0.5-mm type K sheathed thermocouples were placed inside the FRS cladding to measure steady-state and transient temperatures through clad <span class="hlt">melting</span> at 1370/sup 0/C.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1987srto.rept.....L"><span id="translatedtitle">Special relativity theory (one-dimensional case) without the <span class="hlt">postulate</span> on the equality of directions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lyakhovitskij, V. N.</p> <p></p> <p>The consequences of giving up the <span class="hlt">postulate</span> on the equality of positive and negative x axis directions are shown and analyzed for one-dimensional motion of inertial systems. The logic foundations of the theory, except the above <span class="hlt">postulate</span>, coincide with those conventional a lead in particular (in the assumption of equality of positive and negative x axis directions) to the development of standard special relativity theory. The giving up of the above <span class="hlt">postulate</span> results in the conclusion of the possibility of existence of different maximum velocities a and b, corresponding to motions in positive and negative x axis directions. The relativistic factor and the method of velocity composition, due to dependence on a and b, differ from those conventional, but transfer into them on the assumption of equality of directions along the x axis.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015ApPhA.118...23H"><span id="translatedtitle">Superconducting tin <span class="hlt">core</span> fiber</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Homa, Daniel; Liang, Yongxuan; Hill, Cary; Kaur, Gurbinder; Pickrell, Gary</p> <p>2015-01-01</p> <p>In this study, we demonstrated superconductivity in a fiber with a tin <span class="hlt">core</span> and fused silica cladding. The fibers were fabricated via a modified <span class="hlt">melt</span>-draw technique and maintained <span class="hlt">core</span> diameters ranging from 50-300 microns and overall diameters of 125-800 microns. Superconductivity of this fiber design was validated via the traditional four-probe test method in a bath of liquid helium at temperatures on the order of 3.8 K. The synthesis route and fiber design are perquisites to ongoing research dedicated all-fiber optoelectronics and the relationships between superconductivity and the material structures, as well as corresponding fabrication techniques.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2011Litho.125..641N"><span id="translatedtitle">High-pressure partial <span class="hlt">melting</span> and <span class="hlt">melt</span> loss in felsic granulites in the Kutná Hora complex, Bohemian Massif (Czech Republic)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nahodilová, Radmila; Faryad, Shah Wali; Dolejš, David; Tropper, Peter; Konzett, Jürgen</p> <p>2011-07-01</p> <p>Felsic granulites from the Kutná Hora complex in the Moldanubian zone of central Europe preserve mineral assemblage that records transition from early eclogite to granulite facies conditions, and exhibits leucocratic banding, which is interpreted as an evidence for <span class="hlt">melt</span> loss during the decompression path. The granulites are layered and consist of variable proportions of quartz, ternary feldspar, garnet, biotite, kyanite, and rutile. In the mesocratic layers, garnet grains show relatively high Ca contents corresponding to 28-41 mol% grossular end member. They have remarkably flat compositional profiles in their <span class="hlt">cores</span> but their rims exhibit an increase in pyrope and a decrease in grossular and almandine components. In contrast, garnets from the leucocratic layers have relatively low Ca contents (15-26 mol% grossular) that further decrease towards the rims. In addition to modeling of pressure-temperature pseudosections, compositions of garnet <span class="hlt">core</span> composition, garnet rim-ternary feldspar-kyanite-quartz equilibrium, ternary feldspar composition, and the garnet-biotite equilibrium provide five constraints that were used to reconstruct the pressure-temperature path from eclogite through the granulite and amphibolite facies. In both layers, garnet <span class="hlt">cores</span> grew during omphacite breakdown and phengite dehydration <span class="hlt">melting</span> at 940 °C and 2.6 GPa. Subsequent decompression heating to 1020 °C and 2.1 GPa produced Ca- and Fe-poor garnet rims due to the formation of Ca-bearing ternary feldspar and partial <span class="hlt">melt</span>. In both the mesocratic and leucocratic layer, the maximum <span class="hlt">melt</span> productivity was 26 and 18 vol.%, respectively, at peak temperature constrained by the maximum whole-rock H2O budget, ~ 1.05-0.75 wt.%, prior to the <span class="hlt">melting</span>. The preservation of prograde garnet-rich assemblages required nearly complete <span class="hlt">melt</span> loss (15-25 vol.%), interpreted to have occurred at 1000-1020 °C and 2.2-2.4 GPa by garnet mode isopleths, followed by crystallization of small amounts of residual <span class="hlt">melt</span> at 760 °C and 1.0 GPa. Phase formation and <span class="hlt">melt</span> productivity were independently determined by experiments in the piston-cylinder apparatus at 850-1100 °C and 1.7-2.1 GPa. Both the thermodynamic calculations and phase equilibrium experiments suggest that the partial <span class="hlt">melt</span> was produced by the dehydration <span class="hlt">melting</span>: muscovite + quartz = <span class="hlt">melt</span> + K-feldspar + kyanite. The presence of partial <span class="hlt">melt</span> facilitated attainment of mineral equilibria at peak temperature thus eliminating any potential relics of early high-pressure phases such as phengite or omphacite. By contrast, adjacent mafic granulites and eclogites, which apparently share the same metamorphic path but have not undergone partial <span class="hlt">melting</span> commonly preserve relics or inclusions of eclogite-facies mineral assemblages.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://itsisu.diy.concord.org/activities/1465"><span id="translatedtitle">Concord Consortium: <span class="hlt">Melting</span> Ice</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p></p> <p>2011-05-17</p> <p>This activity combines a hands-on lab with a computer simulation, as students investigate and graph the changing temperature of a <span class="hlt">melting</span> ice cube. In the first step, learners use a sensor to monitor temperature as ice <span class="hlt">melts</span> in a cup of water. In the second step, the ice cube is <span class="hlt">melted</span> in a cup of salt water. Interactive graphs allow easy plotting of Temperature vs. Time. The activity concludes with a simulation of the atomic structure of a hot liquid and a cold liquid. Click "Withdraw the Barrier" and watch the changing kinetic energy of the cold liquid particles as they mix with the hot liquid. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015EGUGA..1714597R"><span id="translatedtitle">Mercury's thermal evolution and <span class="hlt">core</span> crystallization regime</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rivoldini, Attilio; Dumberry, Mathieu; Van Hoolst, Tim; Steinle-Neumann, Gerd</p> <p>2015-04-01</p> <p>Unlike the Earth, where the liquid <span class="hlt">core</span> isentrope is less steep than the <span class="hlt">core</span> <span class="hlt">melting</span> temperature, at the lower pressures inside Mercury's <span class="hlt">core</span> the isentrope can be steepper than the <span class="hlt">melting</span> temperature. As a consequence, upon cooling, the isentrope may first cross the <span class="hlt">melting</span> temperature near the <span class="hlt">core</span> mantle boundary and produce iron-rich snow that sinks under gravity and produces buoyant upwellings of iron depleted fluid. Similar to bottom up crystallization, top down crystallization is expected to generate sufficient buoyancy flux to drive magnetic field generation by compositional convection. In this study we model Mercury's thermal evolution by taking into account the formation of iron-rich snow to assess when the conditions for internally magnetic field can be satisfied. We employ a thermodynamic consistent description of the iron high pressure phase diagram and thermoelastic properties of iron alloys as well as the most recent data about the thermal conductivity of <span class="hlt">core</span> materials.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20060024602&hterms=Viscosity&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DViscosity"><span id="translatedtitle">Viscosity Measurement for Tellurium <span class="hlt">Melt</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lin, Bochuan; Li, Chao; Ban, Heng; Scripa, Rosalia N.; Su, Ching-Hua; Lehoczky, Sandor L.</p> <p>2006-01-01</p> <p>The viscosity of high temperature Te <span class="hlt">melt</span> was measured using a new technique in which a rotating magnetic field was applied to the <span class="hlt">melt</span> sealed in a suspended ampoule, and the torque exerted by rotating <span class="hlt">melt</span> flow on the ampoule wall was measured. Governing equations for the coupled <span class="hlt">melt</span> flow and ampoule torsional oscillation were solved, and the viscosity was extracted from the experimental data by numerical fitting. The computational result showed good agreement with experimental data. The <span class="hlt">melt</span> velocity transient initiated by the rotating magnetic field reached a stable condition quickly, allowing the viscosity and electrical conductivity of the <span class="hlt">melt</span> to be determined in a short period.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1403.4147v4"><span id="translatedtitle">Higher-order interference and single-system <span class="hlt">postulates</span> characterizing quantum theory</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Howard Barnum; Markus P. Mueller; Cozmin Ududec</p> <p>2015-01-03</p> <p>We present a new characterization of quantum theory in terms of simple physical principles that is different from previous ones in two important respects: first, it only refers to properties of single systems without any assumptions on the composition of many systems; and second, it is closer to experiment by having absence of higher-order interference as a <span class="hlt">postulate</span>, which is currently the subject of experimental investigation. We give three <span class="hlt">postulates</span> -- no higher-order interference, classical decomposability of states, and strong symmetry -- and prove that the only non-classical operational probabilistic theories satisfying them are real, complex, and quaternionic quantum theory, together with 3-level octonionic quantum theory and ball state spaces of arbitrary dimension. Then we show that adding observability of energy as a fourth <span class="hlt">postulate</span> yields complex quantum theory as the unique solution, relating the emergence of the complex numbers to the possibility of Hamiltonian dynamics. We also show that there may be interesting non-quantum theories satisfying only the first two of our <span class="hlt">postulates</span>, which would allow for higher-order interference in experiments while still respecting the contextuality analogue of the local orthogonality principle.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/24264777"><span id="translatedtitle">Fitting Straight Lines with Replicated Observations by Linear Regression: The Least Squares <span class="hlt">Postulates</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Ana Sayago; Maravillas Boccio; Agustin Asuero</p> <p>2004-01-01</p> <p>The results obtained by statistical techniques are valid if the assumed conditions are satisfied. Fitting straight lines with replicated observations by linear regression is considered in this article paying special attention to the compliance of the least squares <span class="hlt">postulates</span>. Normality, robustness, independence, abscissa free from error, and proper weights are contemplated sequentially in this article. A detailed consideration of multiple</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.springerlink.com/index/q6q880846m271495.pdf"><span id="translatedtitle">Irrational thinking in humans: An evolutionary proposal for Ellis' genetic <span class="hlt">postulate</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>William J. Ruth</p> <p>1992-01-01</p> <p>An evolutionary proposal is outlined for Ellis' genetic <span class="hlt">postulate</span> for irrational thinking in the human species. Evolutionary bases are explored for demanding and grandiose thought constructs (cognitive products) which are either learned and\\/or created during one's lifetime due to a genetic potential to think irrationally (cognitive processes). Demandingness and grandiosity are emphasized because they serve as primary cognitive tendencies in</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://geoffmcfadden.com/McFadden_Lab/Mcfadden_Papers/1994/McFadden_JCS_94.pdf"><span id="translatedtitle">INTRODUCTION Cryptomonad algae are <span class="hlt">postulated</span> to be a chimaera of two</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>McFadden, Geoff</p> <p></p> <p>INTRODUCTION Cryptomonad algae are <span class="hlt">postulated</span> to be a chimaera of two different eukaryotic cells incorporating cryptomonad endosymbiont gene sequences ally them loosely with red algae (Douglas et al., 1991a that the endosymbiont was an early evolutionary intermediate that pre-dates the red algae (Cavalier-Smith, 1992</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=ERIC&redirectUrl=http://files.eric.ed.gov/fulltext/ED141090.pdf"><span id="translatedtitle">A <span class="hlt">Postulated</span> Mechanism That Leads to Materialization and Dematerialization of Matter and to Antigravity.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Bearden, Thomas E.</p> <p></p> <p>This document presents a discussion of the <span class="hlt">postulated</span> mechanism that leads to the materialization and dematerialization of matter and to antigravity. The mechanism also explains why an orbital electron does not radiate energy, in contradiction to classical electromagnetic theory. One of the paradoxes of special relativity is explained. A new model…</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=ERIC&redirectUrl=http://eric.ed.gov/?q=agar+AND+agar&pg=2&id=EJ558809"><span id="translatedtitle">Fun Microbiology: Using a Plant Pathogenic Fungus To Demonstrate Koch's <span class="hlt">Postulates</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Mitchell, James K.; Orsted, Kathy M.; Warnes, Carl E.</p> <p>1997-01-01</p> <p>Describes an experiment using a plant pathogenic fungus in which students learn to follow aseptic techniques, grow and produce spores of a fungus, use a hemacytometer for enumerating spores, prepare serial dilutions, grow and inoculate plants, isolate a pure culture using agar streak plates, and demonstrate the four steps of Koch's <span class="hlt">postulates</span>.…</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.plantsciences.ucdavis.edu/vankessel/publications/clough_et_al.pdf"><span id="translatedtitle">Conventional wisdom <span class="hlt">postulates</span> that leaching losses of N from agriculture systems are dominated by NO3</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>van Kessel, Chris</p> <p></p> <p>for drinking water quality. The extent of DON losses increased with increasing precipitation/irrigation, higher water collection. Total N leaching losses were calculated to be 50 kg N ha­1 yr­1 . The authors393 Conventional wisdom <span class="hlt">postulates</span> that leaching losses of N from agriculture systems are dominated</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://cs.uiowa.edu/~psriniva/Papers/biolink04.pdf"><span id="translatedtitle">Mining MEDLINE: <span class="hlt">Postulating</span> a Beneficial Role for Curcumin Longa in Retinal Diseases</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Srinivasan, Padmini</p> <p></p> <p>Mining MEDLINE: <span class="hlt">Postulating</span> a Beneficial Role for Curcumin Longa in Retinal Diseases Padmini supporting the suggested connection between curcumin and retinal diseases. In particular, curcumin influ, the evidence suggests that curcumin may have a beneficial and therapeutic role in the context of these dis</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/5447416"><span id="translatedtitle">Invariance of the Tetrad <span class="hlt">Postulate</span> as a Fundamental Principle of Unified Field Theory</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Myron W. Evans</p> <p>2008-01-01</p> <p>The tetrad <span class="hlt">postulate</span> is proven to be an invariant of the general coordi- nate transformation in Cartan Riemann geometry. In Einstein Cartan Evans (ECE) unified field theory this inference implies that the ECE Lemma and wave equation are covariant in such a way that only the tetrad eigenfunction changes upon general coordinate transformation. The phase of the eigen- function therefore</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19720034094&hterms=Andrade&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DAndrade"><span id="translatedtitle">Viscosity of the earth's <span class="hlt">core</span>.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gans, R. F.</p> <p>1972-01-01</p> <p>Calculation of the viscosity of the <span class="hlt">core</span> at the boundary of the inner and outer <span class="hlt">core</span>. It is assumed that this boundary is a <span class="hlt">melting</span> transition and the viscosity limits of the Andrade (1934,1952) hypothesis (3.7 to 18.5 cp) are adopted. The corresponding kinematic viscosities are such that the precessional system explored by Malkus (1968) would be unstable. Whether it would be sufficiently unstable to overcome a severely subadiabatic temperature gradient cannot be determined.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20060038287&hterms=thermoacoustic&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dthermoacoustic"><span id="translatedtitle">Thermoacoustic Streaming and Ultrasonic Processing of Low <span class="hlt">Melting</span> <span class="hlt">Melts</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Trinh, E. H.</p> <p>1997-01-01</p> <p>Ultrasonic levitation allows the processing of low <span class="hlt">melting</span> materials both in 1 G as well as in microgravity. The free suspension of the <span class="hlt">melts</span> also facilitates undercooling, permitting the measurements of the physical properties of the metastable liquids.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19940031640&hterms=sulfide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsulfide"><span id="translatedtitle">Preliminary results of sulfide <span class="hlt">melt</span>/silicate wetting experiments in a partially <span class="hlt">melted</span> ordinary chondrite</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jurewicz, Stephen R.; Jones, John H.</p> <p>1994-01-01</p> <p>Recently, mechanisms for <span class="hlt">core</span> formation in planetary bodies have received considerable attention. Most current theories emphasize the need for large degrees of silicate partial <span class="hlt">melting</span> to facilitate the coalescence and sinking of sulfide-metal liquid blebs through a low strength semi-crystalline silicate mush. This scenario is based upon observations that sulfide-metal liquid tends to form circular blebs in partially molten meteorites during laboratory experiments. However, recent experimental work by Herpfer and Larimer indicates that some sulfide-Fe liquids have wetting angles at and slightly below 60 deg in an olivine aggregate, implying an interconnected <span class="hlt">melt</span> structure at any <span class="hlt">melt</span> fraction. Such <span class="hlt">melt</span> interconnectivity provides a means for gravitational compaction and extraction of the majority of a sulfide liquid phase in small planetary bodies without invoking large degrees of silicate partial <span class="hlt">melting</span>. Because of the important ramifications of these results, we conducted a series of experiments using H-chondrite starting material in order to evaluate sulfide-liquid/silicate wetting behavior in a more complex natural system.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://serc.carleton.edu/eet/greenlandmelt/index.html"><span id="translatedtitle">Is Greenland <span class="hlt">Melting</span>?</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p>Betsy Youngman</p> <p></p> <p>Data-centric activity where students explore the connections between an observable change in the cryosphere and its potential impact in the hydrosphere and atmosphere. Students analyze the <span class="hlt">melt</span> extents on the Greenland ice sheet from 1992-2003. Students also learn about how scientists collect the data.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://www.nbclearn.com/climate/cuecard/52577"><span id="translatedtitle"><span class="hlt">Melting</span> Mountain Glaciers</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p>NBC Learn</p> <p>2010-10-07</p> <p>The world's glaciers are shrinking at alarming rates, and many scientists believe it is due to changes in climate. Dr. Lonnie Thompson of Ohio State University and Dr. Douglas Hardy of UMass-Amherst discuss glaciers and how they <span class="hlt">melt</span>, and pay special attention to Africa's tallest mountain, Mt. Kilimanjaro. "Changing Planet" is produced in partnership with the National Science Foundation.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/19391864"><span id="translatedtitle">Maxwell's macroscopic equations, the energy-momentum <span class="hlt">postulates</span>, and the Lorentz law of force.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mansuripur, Masud; Zakharian, Armis R</p> <p>2009-02-01</p> <p>We argue that the classical theory of electromagnetism is based on Maxwell's macroscopic equations, an energy <span class="hlt">postulate</span>, a momentum <span class="hlt">postulate</span>, and a generalized form of the Lorentz law of force. These seven <span class="hlt">postulates</span> constitute the foundation of a complete and consistent theory, thus eliminating the need for actual (i.e., physical) models of polarization P and magnetization M , these being the distinguishing features of Maxwell's macroscopic equations. In the proposed formulation, P(r,t) and M(r,t) are arbitrary functions of space and time, their physical properties being embedded in the seven <span class="hlt">postulates</span> of the theory. The <span class="hlt">postulates</span> are self-consistent, comply with the requirements of the special theory of relativity, and satisfy the laws of conservation of energy, linear momentum, and angular momentum. One advantage of the proposed formulation is that it sidesteps the long-standing Abraham-Minkowski controversy surrounding the electromagnetic momentum inside a material medium by simply "assigning" the Abraham momentum density E(r,t)xH(r,t)/c2 to the electromagnetic field. This well-defined momentum is thus taken to be universal as it does not depend on whether the field is propagating or evanescent, and whether or not the host medium is homogeneous, transparent, isotropic, dispersive, magnetic, linear, etc. In other words, the local and instantaneous momentum density is uniquely and unambiguously specified at each and every point of the material system in terms of the E and H fields residing at that point. Any variation with time of the total electromagnetic momentum of a closed system results in a force exerted on the material media within the system in accordance with the generalized Lorentz law. PMID:19391864</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/48939010"><span id="translatedtitle">Sulfur's impact on <span class="hlt">core</span> evolution and magnetic field generation on Ganymede</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Steven A. Hauck; Jonathan M. Aurnou; Andrew J. Dombard</p> <p>2006-01-01</p> <p>Analysis of the <span class="hlt">melting</span> relationships of potential <span class="hlt">core</span> forming materials in Ganymede indicate that fluid motions, a requirement for a dynamo origin for the satellite's magnetic field, may be driven, in part, either by iron (Fe) “snow” forming below the <span class="hlt">core</span>-mantle boundary or solid iron sulfide (FeS) floating upward from the deep <span class="hlt">core</span>. Eutectic <span class="hlt">melting</span> temperatures and eutectic sulfur contents</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.geoscienze.unipd.it/docs/ditoro/Nielsen_et_al_JGR2008.pdf"><span id="translatedtitle">Frictional <span class="hlt">melt</span> and seismic slip</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>S. Nielsen; G. Di Toro; T. Hirose; T. Shimamoto</p> <p>2008-01-01</p> <p>Frictional <span class="hlt">melt</span> is implied in a variety of processes such as seismic slip, ice skating, and meteorite combustion. A steady state can be reached when <span class="hlt">melt</span> is continuously produced and extruded from the sliding interface, as shown recently in a number of laboratory rock friction experiments. A thin, low-viscosity, high-temperature <span class="hlt">melt</span> layer is formed resulting in low shear resistance. A</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014E%26PSL.408..226L"><span id="translatedtitle">The <span class="hlt">melting</span> curve of Ni to 1 Mbar</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lord, Oliver T.; Wood, Ian G.; Dobson, David P.; Vo?adlo, Lidunka; Wang, Weiwei; Thomson, Andrew R.; Wann, Elizabeth T. H.; Morard, Guillaume; Mezouar, Mohamed; Walter, Michael J.</p> <p>2014-12-01</p> <p>The <span class="hlt">melting</span> curve of Ni has been determined to 125 GPa using laser-heated diamond anvil cell (LH-DAC) experiments in which two <span class="hlt">melting</span> criteria were used: firstly, the appearance of liquid diffuse scattering (LDS) during in situ X-ray diffraction (XRD) and secondly, plateaux in temperature vs. laser power functions in both in situ and off-line experiments. Our new <span class="hlt">melting</span> curve, defined by a Simon-Glatzel fit to the data where TM (K) =[ (PM/18.78±10.20 + 1) ] 1 / 2.42 ± 0.66 × 1726, is in good agreement with the majority of the theoretical studies on Ni <span class="hlt">melting</span> and matches closely the available shock wave <span class="hlt">melting</span> data. It is however dramatically steeper than the previous off-line LH-DAC studies in which determination of <span class="hlt">melting</span> was based on the visual observation of motion aided by the laser speckle method. We estimate the <span class="hlt">melting</span> point (TM) of Ni at the inner-<span class="hlt">core</span> boundary (ICB) pressure of 330 GPa to be TM = 5800 ± 700 K (2 ?), within error of the value for Fe of TM = 6230 ± 500 K determined in a recent in situ LH-DAC study by similar methods to those employed here. This similarity suggests that the alloying of 5-10 wt.% Ni with the Fe-rich <span class="hlt">core</span> alloy is unlikely to have any significant effect on the temperature of the ICB, though this is dependent on the details of the topology of the Fe-Ni binary phase diagram at <span class="hlt">core</span> pressures. Our <span class="hlt">melting</span> temperature for Ni at 330 GPa is ?2500 K higher than that found in previous experimental studies employing the laser speckle method. We find that those earlier <span class="hlt">melting</span> curves coincide with the onset of rapid sub-solidus recrystallization, suggesting that visual observations of motion may have misinterpreted dynamic recrystallization as convective motion of a <span class="hlt">melt</span>. This finding has significant implications for our understanding of the high-pressure <span class="hlt">melting</span> behaviour of a number of other transition metals.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/3575433"><span id="translatedtitle">Physics of Iron at Earth's <span class="hlt">Core</span> Conditions</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>A. Laio; S. Bernard; G. L. Chiarotti; S. Scandolo; E. Tosatti</p> <p>2000-01-01</p> <p>The bulk properties of iron at the pressure and temperature conditions of Earth's <span class="hlt">core</span> were determined by a method that combines first-principles and classical molecular dynamic simulations. The theory indicates that (i) the iron <span class="hlt">melting</span> temperature at inner-<span class="hlt">core</span> boundary (ICB) pressure (330 gigapascals) is 5400 (+\\/-400) kelvin; (ii) liquid iron at ICB conditions is about 6% denser than Earth's outer</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014EGUGA..1613578S"><span id="translatedtitle">Phenocrystal variations in <span class="hlt">melt</span> rocks from Tenoumer impact crater, Mauretania: indicators for varying target contribution and <span class="hlt">melt</span> mixing.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schultze, Dina; Jourdan, Fred; Hecht, Lutz; Reimold, Uwe</p> <p>2014-05-01</p> <p>Impact <span class="hlt">melt</span> rocks from the relatively small (1.9 km in diameter) Tenoumer impact crater (Mauretania) show heterogeneities regarding whole rock chemistry, lithoclast components, their shock deformation degree, amount of vesiculation (<span class="hlt">melt</span> degassing), and contribution of carbonate <span class="hlt">melt</span> phases mingled into silicate <span class="hlt">melt</span> matrix. These heterogeneities have two main reasons: First, due to the restricted size of the impact crater there was probably no coherent <span class="hlt">melt</span> pool where a homogeneous mixture of the target rocks could be achieved. Therefore, impact <span class="hlt">melting</span> of target lithologies resulted in locally different, often incomplete mixing of <span class="hlt">melts</span> from chemically very diverse target rocks. Second, <span class="hlt">melt</span> rock heterogeneity occurs at the thin section scale and is due to fast cooling during and after the dynamic ejection and emplacement process. The overall period of crystal growth has been extremely short, so that chemical equilibration of the phases could not be achieved. <span class="hlt">Melt</span> mixing processes involved in impact <span class="hlt">melt</span> formation are, thus, recorded in non-equilibrium growth features. Mixing processes between chemically different <span class="hlt">melt</span> phases and the formation of hybrid <span class="hlt">melts</span> can be observed in the case of Tenoumer impact <span class="hlt">melts</span> on a millimeter scale. Due to extreme cooling rates, different mixing stages are preserved in the varied parageneses and mineral chemistry of phenocrysts. Different silicate <span class="hlt">melt</span> matrices show different phenocryst parageneses in response to slight variation of whole-rock chemistry and, thus, represents a useful indicator of precursor rock contribution to different impact <span class="hlt">melts</span>. Basalt-andesitic (Mg,Fe-rich) <span class="hlt">melt</span> matrices are after all composed of up to 20 vol% of forsterite-rich olivine-microphenocrysts. Decreasing Fe,Mg-amounts of <span class="hlt">melt</span> matrix results in decreasing modal abundance of olivine, which shows progressively higher fayalite composition. These observations correlate with changing amounts of felsic and basic lithoclasts (granite, granitic gneiss, and gabbro). Different pyroxene generations occur including significant compositional zonation with widely variable CaO, MgO and FeO contents (En7-80, Wo4-50, Fs9-41). Pyroxene evolution (<span class="hlt">core</span>-rim-zonation) changes from En-Di to Di-Hd as CaO content of the <span class="hlt">melt</span> matrix oversteps 9 wt%. Strong variations in CaO content that do not correlate with increasing MgO and FeO contents are interpreted as incorporation of CaO from carbonate <span class="hlt">melts</span> into the silicate <span class="hlt">melt</span> phase. The presents of intermingled carbonate <span class="hlt">melt</span> schlieren support this hypothesis. New 40Ar/39Ar dating on three of the studied <span class="hlt">melt</span> rock samples resulted in a - preferred - age of 1.57 ± 0.14 Ma for the Tenoumer impact event. This impact age is significantly different from previous dating results of 21 ± 10 ka and 2.5 ± 0.5 Ma.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFMDI13B4270P"><span id="translatedtitle">Experimental Investigations of the Deep Earth's Mantle <span class="hlt">Melting</span> Properties</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pesce, G.; Andrault, D.; Manthilake, G. M.; Bolfan-Casanova, N.; Novella, D.; Chantel, J.; Guignot, N.</p> <p>2014-12-01</p> <p>Studying the <span class="hlt">melting</span> properties of the mantle is fundamental to understand the global dynamics of our planet. Already in the early stages of its history, Earth experienced extensive <span class="hlt">melting</span> events leading to the formation of a magma ocean, due to the massive energy released by large-scale meteoritic impacts, radiogenic decay and <span class="hlt">core</span>-mantle gravitational segregation. Partial <span class="hlt">melting</span> however still plays a key role in today's mantle's dynamics. Seismic observations have in fact highlighted the presence of anomalies in the upper mantle, atop the 410 km discontinuity. These regions, called ultra-low velocity zones, show a significant reduction in shear wave velocity, compatible with the presence of partial <span class="hlt">melting</span>. We studied the <span class="hlt">melting</span> properties of the mantle using in situ X-ray diffraction experiments and electrical conductivity measurements at high pressure and high temperature. Both technics are very sensitive to the presence of liquid in the sample. They provide accurate information not only on the evolution with pressure of the solidus temperature, but also on the degree of partial <span class="hlt">melting</span> with increasing temperature. Our samples consisted of a synthetic CI chondrite glass, a "proxy" composition for the primitive mantle after <span class="hlt">core</span> segregation. Pressures up to 25 GPa (upper/lower mantle limit, at 670 km depth) were generated by the multi-anvil press. Our results suggest that previous studies overestimated by ~300 K the solidus temperature, probably due to a lack of resolution in determining low degrees of partial <span class="hlt">melting</span> in their experimental procedure, compared to the in situexperiments presented here. Our results imply that partial <span class="hlt">melting</span> could happen more frequently than initially expected, particularly in mantle regions where incompatible elements and volatiles are concentrated.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1202.2747v2"><span id="translatedtitle">Evolution of the CPT Invariance into a Basic <span class="hlt">Postulate</span> in Physics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Guang-jiong Ni; Suqing Chen; Jianjun Xu</p> <p>2012-07-23</p> <p>Einstein-Podolsky-Rosen's paper in 1935 is discussed in parallel with an EPR experiment on $K^0\\bar{K}^0$ system in 1998, yielding a strong hint of distinction in both wave-function and operators between particle and antiparticle at the level of quantum mechanics (QM). Then it is proposed that the CPT invariance in particle physics leads naturally to a basic <span class="hlt">postulate</span> that the (newly defined) space-time inversion (${\\bf x}\\to -{\\bf x},t\\to -t$) is equivalent to the transformation between particle and its antiparticle. The evolution of this <span class="hlt">postulate</span> from nonrelativistic QM via relativistic QM till the quantum field theory is discussed in some detail. The Klein paradox for both Klein-Gordon equation and Dirac equation is also discussed. Keywords: CPT invariance, Antiparticle, Quantum mechanics, Quantum field theory</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/19223256"><span id="translatedtitle">Post-traumatic pseudolipomas--a review and <span class="hlt">postulated</span> mechanisms of their development.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Galea, Laurence A; Penington, Anthony J; Morrison, Wayne A</p> <p>2009-06-01</p> <p>Post-traumatic pseudolipomas develop in areas of the body that have been subjected to acute, severe, blunt trauma and chronic trauma. This study aimed to review the literature for reports of post-traumatic pseudolipomas on Medline and identify the possible mechanisms of their development. In the literature, 124 such cases were identified relating to case reports and case series; of these, 98 occurred in females and 26 in males. The majority of the cases occurred secondary to severe, acute, blunt trauma. The initial <span class="hlt">postulated</span> mechanisms for development of post-traumatic pseudolipomas were anatomically and mechanically based. Recently, it was shown that there is a close relationship between inflammation and adipogenesis. Blunt trauma results in an inflammatory process. We <span class="hlt">postulate</span> that post-traumatic pseudolipoma development occurs as a result of inflammatory triggers and an optimal local milieu at the site of development by making an analogy to an in vivo murine tissue engineering model for neo-adipogenesis. PMID:19223256</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6434146"><span id="translatedtitle">SAS4A: A computer model for the analysis of hypothetical <span class="hlt">core</span> disruptive accidents in liquid metal reactors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tentner, A.M.; Birgersson, G.; Cahalan, J.E.; Dunn, F.E.; Kalimullah; Miles, K.J.</p> <p>1987-01-01</p> <p>To ensure that the public health and safety are protected under any accident conditions in a Liquid Metal Fast Breeder Reactor (LMFBR), many accidents are analyzed for their potential consequences. The SAS4A code system, described in this paper, provides such an analysis capability, including the ability to analyze low probability events such as the Hypothetical <span class="hlt">Core</span> Disruptive Accidents (HCDAs). The SAS4A code system has been designed to simulate all the events that occur in a LMFBR <span class="hlt">core</span> during the initiating phase of a Hypothetical <span class="hlt">Core</span> Disruptive Accident. During such <span class="hlt">postulated</span> accident scenarios as the Loss-of-Flow and Transient Overpower events, a large number of interrelated physical phenomena occur during a relatively short time. These phenomena include transient heat transfer and hydrodynamic events, coolant boiling and fuel and cladding <span class="hlt">melting</span> and relocation. During to the strong neutronic feedback present in a nuclear reactor, these events can significantly influence the reactor power. The SAS4A code system is used in the safety analysis of nuclear reactors, in order to estimate the energetic potential of very low probability accidents. The results of SAS4A simulations are also used by reactor designers in order to build safer reactors and eliminate the possibility of any accident which could endanger the public safety.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1993alab.reptX....W"><span id="translatedtitle"><span class="hlt">Melt</span> spinning study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Workman, Gary L.; Rathz, Thomas</p> <p>1993-04-01</p> <p>Containerless processing of materials provides an excellent opportunity to study nucleation phenomena and produce unique materials, primarily through the formation of metastable phases and deep undercoolings. Deep undercoolings can be readily achieved in falling drops of molten material. Extended solute solubilities and greatly refined microstructures can also be obtained in containerless processing experiments. The Drop Tube Facility at Marshall Space Flight Center has played an important role in enhancing that area of research. Previous experiments performed in the Drop Tube with refractory metals has shown very interesting microstructural changes associated with deep undercoolings. It is apparent also that the microstructure of the deep undercooled species may be changing due to the release of the latent heat of fusion during recalescence. For scientific purposes, it is important to be able to differentiate between the microstructures of the two types of metallic species. A review of the literature shows that although significant advances have been made with respect to the engineering aspects of rapid solidification phenomena, there is still much to be learned in terms of understanding the basic phenomena. The two major ways in which rapid solidification processing provides improved structures and hence improved properties are: (1) production of refined structures such as fine dendrites and eutectics, and (2) production of new alloy compositions, microstructures, and phases through extended solid solubility, new phase reaction sequences, and the formation of metallic-glass microstructures. The objective of this work has been to determine the optimal methodology required to extract this excess energy without affecting the thermo-physical parameters of the under-cooled <span class="hlt">melt</span>. In normal containerless processing experiments recalescence occurs as the <span class="hlt">melt</span> returns toward the <span class="hlt">melting</span> point in order to solidify. A new type of experiment is sought in which the resultant microstructure of the undercooled species is frozen in without going through the <span class="hlt">melting</span> point regime and subsequent near equilibrium solidification of the remaining liquid. This experimental approach entails the design of an appropriate <span class="hlt">melt</span> spinning system which is compatible with Drop Tube operations and processing constraints. That work is the goal of this study.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.ma.utexas.edu/users/gilbert/M333L/chp3.pdf"><span id="translatedtitle">NON-EUCLIDEAN GEOMETRIES In the previous chapter we began by adding Euclid's Fifth <span class="hlt">Postulate</span> to his five common</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>1 Chapter 3 NON-EUCLIDEAN GEOMETRIES In the previous chapter we began by adding Euclid's Fifth-dimensional canvas. Both Euclidean and hyperbolic geometry can be realized in this way, as later sections will show <span class="hlt">Postulate</span> to his five common notions and first four <span class="hlt">postulates</span>. This produced the familiar geometry</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/55835157"><span id="translatedtitle">Impact <span class="hlt">melt</span> volume estimates in small-to-medium sized craters on the Moon from the Lunar Orbiter Laser Altimeter (LOLA) and Lunar Reconnaissance Orbiter Camera (LROC)</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>O. S. Barnouin; K. D. Seelos; A. McGovern; B. W. Denevi; M. T. Zuber; D. E. Smith; M. S. Robinson; G. A. Neumann; E. Mazarico; M. H. Torrence</p> <p>2010-01-01</p> <p>Direct measurements of the volume of <span class="hlt">melt</span> generated during cratering have only been possible using data acquired at terrestrial craters. These measurements are usually the result of areal mapping efforts, drill <span class="hlt">core</span> investigations, and assessments of the amount of erosion a crater and its <span class="hlt">melt</span> sheet might have undergone. Good data for <span class="hlt">melt</span> volume are needed to further test and</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6947672"><span id="translatedtitle">Correlation for downward <span class="hlt">melt</span> penetration into a miscible low-density substrate</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fang, L.J.; Cheung, F.B.; Pedersen, D.R.; Linehan, J.H.</p> <p>1984-01-01</p> <p>Downward penetration of a sacrificial bed material or a concrete basemat structure by an overlying layer of <span class="hlt">core</span> <span class="hlt">melt</span> resulting from a hypothetical <span class="hlt">core</span> disruptive accident has been a major issue in post accident heat removal studies. One characteristic feature of this problem is that the solid substrate, when molten, is miscible with and lighter than the <span class="hlt">core</span> <span class="hlt">melt</span> so that the rate of penetration is strongly dependent upon the motion of natural convection in the <span class="hlt">melt</span> layer driven by the density difference between the <span class="hlt">core</span> <span class="hlt">melt</span> and the molten substrate. This fundamentally interesting and technologically important problem has been investigated by a number of researchers. Significantly different <span class="hlt">melting</span> rates, however, were observed in these studies. Questions concerning the occurrence of flow transition and its effect on <span class="hlt">melt</span> penetration remain to be answered. To promote the understanding of the phenomena and to strengthen the data base of <span class="hlt">melt</span> penetration, simulation experiments were conducted using various kinds of salt solutions (KI, NaCl, CaCl/sub 2/, and MgCl/sub 2/ solutions) as the working fluid and an air-bubble-free ice slab as the solid substrate.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2000GeoRL..27..421B"><span id="translatedtitle">Seismic velocity decrement ratios for regions of partial <span class="hlt">melt</span> in the lower mantle</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Berryman, James G.</p> <p>2000-02-01</p> <p>For regions of partial <span class="hlt">melt</span> in the lower mantle, both compressional and shear wave velocities decrease monotonically with increasing <span class="hlt">melt</span> volume fraction. Those regions close to the <span class="hlt">core</span>-mantle boundary thought to contain partial <span class="hlt">melt</span> have a velocity decrement ratio (relative change in shear velocity over relative change of compressional velocity) of about 3. Arguments based on effective medium theories have been given to show that such high values of this ratio are predicted for partial <span class="hlt">melt</span> systems. The present work confirms the value of 3 near the <span class="hlt">core</span>-mantle boundary. It is shown, furthermore, that this velocity decrement ratio can be estimated without detailed knowledge of, or assumptions about, the microstructure of the partial <span class="hlt">melt</span> system by using Gassmann’s equation of poroelasticity together with some reasonable assumptions about the change (or lack of change) of the density and bulk modulus for lower mantle pressure and temperature conditions.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/945774"><span id="translatedtitle"><span class="hlt">Melting</span> of Ice under Pressure</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Schwegler, E; Sharma, M; Gygi, F; Galli, G</p> <p>2008-07-31</p> <p>The <span class="hlt">melting</span> of ice under pressure is investigated with a series of first principles molecular dynamics simulations. In particular, a two-phase approach is used to determine the <span class="hlt">melting</span> temperature of the ice-VII phase in the range of 10 to 50 GPa. Our computed <span class="hlt">melting</span> temperatures are consistent with existing diamond anvil cell experiments. We find that for pressures between 10 to 40 GPa, ice <span class="hlt">melts</span> as a molecular solid. For pressures above {approx}45 GPa there is a sharp increase in the slope of the <span class="hlt">melting</span> curve due to the presence of molecular dissociation and proton diffusion in the solid, prior to <span class="hlt">melting</span>. The onset of significant proton diffusion in ice-VII as a function of increasing temperature is found to be gradual and bears many similarities to that of a type-II superionic solid.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20050182087&hterms=Melting+point&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3D%2528Melting%2Bpoint%2529"><span id="translatedtitle"><span class="hlt">Melting</span> in Martian Snowbanks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zent, A. P.; Sutter, B.</p> <p>2005-01-01</p> <p>Precipitation as snow is an emerging paradigm for understanding water flow on Mars, which gracefully resolves many outstanding uncertainties in climatic and geomorphic interpretation. Snowfall does not require a powerful global greenhouse to effect global precipitation. It has long been assumed that global average temperatures greater than 273K are required to sustain liquid water at the surface via rainfall and runoff. Unfortunately, the best greenhouse models to date predict global mean surface temperatures early in Mars' history that differ little from today's, unless exceptional conditions are invoked. Snowfall however, can occur at temperatures less than 273K; all that is required is saturation of the atmosphere. At global temperatures lower than 273K, H2O would have been injected into the atmosphere by impacts and volcanic eruptions during the Noachian, and by obliquity-driven climate oscillations more recently. Snow cover can accumulate for a considerable period, and be available for <span class="hlt">melting</span> during local spring and summer, unless sublimation rates are sufficient to remove the entire snowpack. We decided to explore the physics that controls the <span class="hlt">melting</span> of snow in the high-latitude regions of Mars to understand the frequency and drainage of snowmelt in the high martian latitudes.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/124475"><span id="translatedtitle">Numerical simulation and experimental verification of <span class="hlt">melt</span> front advancements in coinjection molding process</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chen, S.C.; Hsu, K.F. [Chung Yuan Univ., Chung-Li (Taiwan, Province of China). Mechanical Engineering Dept.</p> <p>1995-10-01</p> <p>Experimental studies of polymer <span class="hlt">melt</span> flow in the mold filling stage of the coinjection molding process have been carried out using sequential injection of transparent and colored polystyrene resin. Simulations are also developed to predict the <span class="hlt">melt</span> front advancements of both skin and <span class="hlt">core</span> <span class="hlt">melts</span>. A control volume/finite element method employed within each grid layer of the gapwise direction is applied to trace the <span class="hlt">melt</span> front advancements for both skin and <span class="hlt">core</span> materials. Numerical simulations show reasonably good consistency with experimental results in both skin and <span class="hlt">core</span> material distribution. However, the simulation accuracy can be improved further if edge effect is taken into account using the shape factor as a geometrical correction.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014EPJD...68..292V"><span id="translatedtitle">Molecular dynamics simulations of the <span class="hlt">melting</span> of KCl nanoparticles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Van Sang, Le; Thi Thuy Huong, Ta; Nguyen Tue Minh, Le</p> <p>2014-10-01</p> <p>Molecular dynamics (MD) simulations are used to investigate the thermodynamic properties and structural changes of KCl spherical nanoparticles at various sizes (1064, 1736, 2800, 3648, 4224 and 5832 ions) upon heating. The <span class="hlt">melting</span> temperature is dependent on both the size and shape of KCl models, and the behaviour of the first order phase transition is also found in the present work. The surface <span class="hlt">melting</span> found here is different from the <span class="hlt">melting</span> phenomena of KCl models or other alkali halides studied in the past. In the premelting stage, a mixed phase containing liquid and solid ions covers the surface of nanoparticles. The only peak of heat capacity spreads out a significant segment of temperature, probably exhibiting both heterogeneous <span class="hlt">melting</span> on the surface and homogeneous <span class="hlt">melting</span> in the <span class="hlt">core</span>. The coexistence of two <span class="hlt">melting</span> mechanisms, homogeneous and heterogeneous ones, in our model is unlike those considered previously. We also found that the critical Lindemann ratio of the KCl nanoparticle becomes much more stable when the size of the nanoparticle is of the order of thousands of ions. A picture of the structural evolution upon heating is studied in more detail via the radial distribution function (RDF) and coordination numbers. Our results are in a good agreement with previous MD simulations and experimental observations.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2007AmJPh..75..713D"><span id="translatedtitle">Test of the second <span class="hlt">postulate</span> of special relativity using positron annihilation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dryzek, Jerzy; Singleton, Douglas</p> <p>2007-08-01</p> <p>An experiment to directly test the second <span class="hlt">postulate</span> of special relativity is described. The speed of photons, resulting from the annihilation of either thermal positrons or in-flight positrons (moving with relativistic velocity), is measured using two complementary variations of the same basic experiment. For both at rest and moving positrons the constancy of the speed of light was confirmed to an accuracy of approximately 1%. This apparatus can be used in an advanced undergraduate laboratory and also used to place limits on alternative theories to special relativity that have transformations other than the Lorentz transformation.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1992Metic..27R.284R"><span id="translatedtitle">A Distinct Poikilitic Impact <span class="hlt">Melt</span> Rock from the Apollo 17 Landing Site that is not from the Serenitatis <span class="hlt">Melt</span> Sheet</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ryder, G.</p> <p>1992-07-01</p> <p>A poikilitic impact <span class="hlt">melt</span> rock fragment in a sample from Boulder 1, Station 2, is distinct and important: 1) no such poikilitic- textured <span class="hlt">melt</span> rock has been observed in Boulder 1 before; 2) although superficially similar to typical coarse samples of the Serenitatis <span class="hlt">melt</span> sheet, it is chemically and petrographically distinct from them. It extends the known range of significant low-K Fra Mauro impact <span class="hlt">melt</span> rock compositions that potentially can provide us with information about lunar crustal components and structure. Lunar sample 72255 is a fine-grained aphanitic <span class="hlt">melt</span> representing Boulder 1 on the South Massif. It contains many clasts, including granitic fragments, but more typically fine basaltic-composition impact <span class="hlt">melts</span>, feldspathic breccias, and granulitic impactites. The aphanitic <span class="hlt">melt</span> groundmass of 72255 is distinct in composition from typical Serenitatis impact <span class="hlt">melt</span> samples, but even if it formed in a distinct event, the relative ages are radiometrically indistinguishable (at present). The discovery of a poikilitic impact <span class="hlt">melt</span> rock fragment during new investigations of 72255 at first led me to conclude that Boulder 1 contained fragments of the Serenitatis <span class="hlt">melt</span> sheet, hence must be slightly younger. However, a closer inspection and analysis reveals that this fragment is distinct from the Serenitatis <span class="hlt">melt</span> sheet samples, thus stratigraphy cannot be inferred from it. The distinction of the fragment instead gives it a different potential significance, that of furthering our understanding of crustal components. The fragment was observed in saw-cut faces as a sharply defined pale brown clast embedded in the groundmass. It was about 7 mm in diameter, although not all was exposed. The fragment was crystalline, with dark brown pyroxenes, white plagioclases, and a pale yellow minor phase. Its texture and the presence of small vugs suggested an igneous rock, and it was chipped for chemical and thin section studies. The thin section revealed a clast-bearing impact <span class="hlt">melt</span> rock with pyroxene oikocrysts, plagioclase chadacrysts, and ilmenite chains, very similar to Apollo 15, 16, and 17 coarser poikilitic impact <span class="hlt">melt</span> samples. The chemistry of its mineral phases (both clasts and groundmass) is identical with Apollo 17 poikilitic boulder samples, e.g., pigeonite oikocrysts with a range of En82- 70. It does contain rather more high-Ca pyroxene oikocrysts than do the poikilitic boulders: pig/cpx of 2 rather than about 4. The oikocrysts, about a millimeter across, contain many plagioclase chadacrysts. They are normally zoned outward from their <span class="hlt">cores</span>, with superimposed normal zoning toward each plagioclase chadacryst. The clasts are dominantly plagioclases, with some olivine and rare lithic fragments such as a feldspathic granulite. A small amount of olivine may have crystallized from the <span class="hlt">melt</span>, but none forms oikocrysts. The INAA shows the <span class="hlt">melt</span> rock fragment to be a little higher in Ca and a little lower in Fe than the poikilitic boulders. The main difference is the much lower abundance of all large ion lithophile elements in the new clast, e.g., Sm 8 ppm cf. 15 ppm in the poikilitic boulders. This result was confirmed by analysis of both a second chip and a second analysis of the first chip. The difference is far too great to result merely from a larger clast content in the new fragment; the chemistry suggests an entirely separate impact event, not a phase of Serenitatis. The higher modal clinopyroxene suggests the same. The <span class="hlt">melt</span> rock fragment is also distinct from the few other unique Apollo 17 <span class="hlt">melts</span>, such as 76055, or any of the Apollo 15 and 16 poikilitic <span class="hlt">melts</span>. It extends the range of known low-K Fra Mauro samples, and gives us more potential to understand both the lunar crust, and Boulder 1. Its investigation will continue with more complete mineralogical and chemical data, an age determination, and a detailed comparison with all other known poikilitic <span class="hlt">melt</span> samples.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/5705341"><span id="translatedtitle">Assessment of value-impact associated with the elimination of <span class="hlt">postulated</span> pipe ruptures from the design basis for nuclear power plants</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Holman, G.S.; Chou, C.K.</p> <p>1985-03-29</p> <p>The US Nuclear Regulatory Commission is proposing to amend the regulations that currently require that the design basis for nuclear power plants include the <span class="hlt">postulation</span> of dynamic effects from loss of coolant accidents up to and including the double-ended rupture of the largest pipe in the reactor coolant system. Proposed modifications would allow analyses to serve as a sufficient basis for excluding dynamic effects, including but not necessarily limited to pipe whip and jet impingement, associated with specific pipe ruptures. Only dynamic effects would be impacted; current design requirements for containment sizing and discharge capacity of emergency <span class="hlt">core</span> cooling systems would remain unchanged. This report presents a detailed analysis of value-impact associated with the proposed amendment for PWR reactor coolant loop piping and for BWR recirculation loop piping. The effect of extending application of the proposed rule change to other piping systems is also assessed in a less quantitative manner.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19780057183&hterms=mines+canada&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmines%2Bcanada"><span id="translatedtitle">Manicouagan impact <span class="hlt">melt</span>, Quebec. II - Chemical interrelations with basement and formational processes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Grieve, R. A. F.; Floran, R. J.</p> <p>1978-01-01</p> <p>The basement rocks of Manicouagan exhibit a wide compositional range (40-72% SiO2). Least squares mixing calculations indicate that the average composition of the Manicouagan <span class="hlt">melt</span> sheet can be modeled for 9 major and 11 trace elements by a mixture of 4.5% anorthosite, 55.5% mafic gneiss, and 40.0% tan gneiss with a granitic-granodioritic composition. The underrepresentation of anorthosite relative to its present distribution is considered. The homogeneous composition of the <span class="hlt">melt</span> (57.75 + or - 1.21% SiO2) relative to that of the <span class="hlt">postulated</span> target is explained in a model outlining the dynamic conditions existing during the formation of the <span class="hlt">melt</span> and its accompanying movement into the excavated cavity.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/21062315"><span id="translatedtitle">An Improved Method for <span class="hlt">Postulating</span> Fabrication Flaws in Reactor Pressure Vessels for Structural Integrity Evaluation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Simonen, F.A. [Pacific Northwest National Laboratory, P.O. Box 999 Richland, WA 99352 (United States); Dickson, T.L. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States)</p> <p>2002-07-01</p> <p>This paper presents an improved model for <span class="hlt">postulating</span> fabrication flaws in reactor pressure vessels (RPVs) and for the treatment of measured flaw data by probabilistic fracture mechanics (PFM) codes that are used for structural integrity evaluations. The model used to develop the current pressurized thermal shock (PTS) regulations conservatively <span class="hlt">postulated</span> that all fabrication flaws were inner-surface breaking flaws. To reduce conservatisms and uncertainties in flaw-related inputs, the United States Nuclear Regulatory Commission (USNRC) has supported research at Pacific Northwest National Laboratory (PNNL) that has resulted in data on fabrication flaws from non-destructive and destructive examinations of actual RPV material. Statistical distributions have been developed to characterize the number and sizes of flaws in the various material regions of a vessel. The regions include the main seam welds, repair welds, base metal of plates and forgings, and the cladding that is applied to the inner surface of the vessel. Flaws are also characterized as being located within the interior of these regions or along the weld fusion lines that join the regions. Flaws are taken that occur at random locations relative to the embrittled inner region of the vessel. The probabilistic fracture mechanics model associates each of the simulated flaw types with the fracture properties of the region being addressed. (authors)</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/physics/0512036v1"><span id="translatedtitle">Attempt at clarification of Einstein's <span class="hlt">postulate</span> of constancy of light velocity</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Wang Guowen</p> <p>2005-12-05</p> <p>We have realized that under Lorentz transformations the tick number of a moving common clock remains unchanged, that is, the hand of the clock never runs slow, but the time interval between its two consecutive ticks contracts, so the relative time has to be recorded by using the tau-clocks required by the transformations, instead of unreal slowing clocks. Thus it is argued that using rest common clocks or the equivalent the measured velocity of light emitted by a moving source, which is quasi-velocity of foreign light, is dependent of the source velocity. Nevertheless, the velocity of foreign light that should be measured by using tau-clocks is independent of the source velocity. The velocity of native light emitted by a rest source obeys the <span class="hlt">postulate</span> of relativity in accordance with both Maxwell equations and the result of Michelson-Morley experiment. On the other hand, the velocity of foreign light obeys both Ritz's emission theory except the Lorentz factor and the <span class="hlt">postulate</span> of constancy of light velocity if measured by using tau-clocks. Thus the emission theory does not conflict with special relativity. The present argument leads to a logical consequence that the so-called positive conclusions from experiments testing constancy of the velocity of light emitted by moving sources if using common clocks or the equivalent, instead of tau-clocks, exactly contradicts Lorentz transformations.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/22711937"><span id="translatedtitle">Investigation of reactions <span class="hlt">postulated</span> to occur during inhibition of ribonucleotide reductases by 2'-azido-2'-deoxynucleotides.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dang, Thao P; Sobczak, Adam J; Mebel, Alexander M; Chatgilialoglu, Chryssostomos; Wnuk, Stanislaw F</p> <p>2012-07-01</p> <p>Model 3'-azido-3'-deoxynucleosides with thiol or vicinal dithiol substituents at C2' or C5' were synthesized to study reactions <span class="hlt">postulated</span> to occur during inhibition of ribonucleotide reductases by 2'-azido-2'-deoxynucleotides. Esterification of 5'-(tert-butyldiphenylsilyl)-3'-azido-3'-deoxyadenosine and 3'-azido-3'-deoxythymidine (AZT) with 2,3-S-isopropylidene-2,3-dimercaptopropanoic acid or N-Boc-S-trityl-L-cysteine and deprotection gave 3'-azido-3'-deoxy-2'-O-(2,3-dimercaptopropanoyl or cysteinyl)adenosine and the 3'-azido-3'-deoxy-5'-O-(2,3-dimercaptopropanoyl or cysteinyl)thymidine analogs. Density functional calculations predicted that intramolecular reactions between generated thiyl radicals and an azido group on such model compounds would be exothermic by 33.6-41.2 kcal/mol and have low energy barriers of 10.4-13.5 kcal/mol. Reduction of the azido group occurred to give 3'-amino-3'-deoxythymidine, which was <span class="hlt">postulated</span> to occur with thiyl radicals generated by treatment of 3'-azido-3'-deoxy-5'-O-(2,3-dimercaptopropanoyl)thymidine with 2,2'-azobis-(2-methyl-2-propionamidine) dihydrochloride. Gamma radiolysis of N(2)O-saturated aqueous solutions of AZT and cysteine produced 3'-amino-3'-deoxythymidine and thymine most likely by both radical and ionic processes. PMID:22711937</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.research.ed.ac.uk/portal/files/11336250/Crystal_Melt_Redacted.pdf"><span id="translatedtitle">Edinburgh Research Explorer Crystal<span class="hlt">Melt</span> Relationships and the Record of Deep Mixing and</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Millar, Andrew J.</p> <p></p> <p>macrocrysts are made up of three distinct domains: high-anorthite <span class="hlt">cores</span>, oscillatory zoned mantles and low-anorthite are in equilibrium with the carrier liquid erupted at the surface. High- anorthite <span class="hlt">cores</span> are more primitive than any to the carrier liquid. High-anorthite crystals may have grown from depleted, high-Ca/Na <span class="hlt">melts</span> of the shallow</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2012E%26PSL.335...48O"><span id="translatedtitle">The Manicouagan impact <span class="hlt">melt</span> sheet: Evidence for isotopic homogenization with limited assimilation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>O'Connell-Cooper, Catherine D.; Dickin, Alan P.; Spray, John G.</p> <p>2012-06-01</p> <p>The Rb-Sr, Pb-Pb and Sm-Nd isotope chemistry of impact-generated <span class="hlt">melt</span> and target rocks has been determined from the 214 Ma, ˜90 km rim-diameter, Manicouagan impact structure of Canada. Fifty-seven samples were obtained from 8 field sites and 11 drill <span class="hlt">core</span> sites across the impact <span class="hlt">melt</span> sheet, located on the 55 km-diameter central island (Île René-Levasseur). The results reveal that the impact <span class="hlt">melt</span>, though locally differentiated via fractional crystallization, was isotopically homogenized during its formation following its derivation primarily from charnockites and mesocratic gneisses. The isotopic signatures of the target rocks indicate that the protolith for the <span class="hlt">melt</span> was the Proterozoic Manicouagan Imbricate Zone, and that the underlying Archean Gagnon Terrane was not involved in <span class="hlt">melt</span> production, or its subsequent modification via assimilation, despite impact <span class="hlt">melt</span> resting on Archean lithologies in the southwest sector of the <span class="hlt">melt</span> sheet. Limited assimilation of the footwall in this sector is attributed to the relatively rapid cooling of a thinner peripheral <span class="hlt">melt</span> body (<100 m), primarily through contact with cooler footwall and clasts. Assimilation at the base of the thicker (up to 1.4 km thick) <span class="hlt">melt</span> sections, near the center of the structure is attributed to secondary <span class="hlt">melting</span> of centrally uplifted anorthosite, which locally modified the original isotopic signature.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://homepages.uni-tuebingen.de/wolfgang.siebel/pdffiles/mantle_6.pdf"><span id="translatedtitle">How does the mantle <span class="hlt">melt</span>?How does the mantle <span class="hlt">melt</span>? 1) Increase the temperature</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Siebel, Wolfgang</p> <p></p> <p>: ­ Decompression <span class="hlt">melting</span> · Passive asthenospheric upwelling at mid- ocean ridges · Rising plume head at "hot spotsHow does the mantle <span class="hlt">melt</span>?How does the mantle <span class="hlt">melt</span>? 1) Increase the temperature <span class="hlt">Melting</span> by raising the temperature<span class="hlt">Melting</span> by raising the temperature Solidus: Temperature of <span class="hlt">melting</span>, increases with depth (P) #12</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://phycomp.technion.ac.il/~phsorkin/thesis/thesis.ps.gz"><span id="translatedtitle">POINT DEFECTS, LATTICE STRUCTURE AND <span class="hlt">MELTING</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Adler, Joan</p> <p></p> <p>POINT DEFECTS, LATTICE STRUCTURE AND <span class="hlt">MELTING</span> SLAVA SORKIN #12; POINT DEFECTS, LATTICE STRUCTURE . . . . . . . . . . . . . . . . . . . . 12 1.5 <span class="hlt">Melting</span> theories based on point defects . . . . . . . . . . . . . . . . 14 1.6 Cooperative of vanadium . . . . . . . . . . . . . . . . . . . . . . 55 4.2 Bulk <span class="hlt">melting</span> and point defects</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/20709817"><span id="translatedtitle">Bulk nanostructured alloys prepared by flux <span class="hlt">melting</span> and <span class="hlt">melt</span> solidification</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Shen, T.D.; Schwarz, R.B.; Zhang, X. [Materials Science and Technology Division, Los Alamos National Laboratory, MS G755, MST-8, Los Alamos, New Mexico 87545 (United States); Department of Mechanical Engineering, Texas A and M University, College Station, Texas 77843 (United States)</p> <p>2005-10-03</p> <p>We have prepared bulk nanostructured Ag{sub 60}Cu{sub 40} alloys by a flux-<span class="hlt">melting</span> and <span class="hlt">melt</span>-solidification technique. The flux purifies the <span class="hlt">melts</span>, leading to a large undercooling and nanometer-sized microstructure. The as-prepared alloys are composed of nanolayered Ag and Cu within micrometer-sized grains. The bulk nanostructured alloys have an ultimate tensile strength of approximately 560 MPa, similar yield strength in tension and compression, elongation of 7% in tension, strain hardening exponent of 0.1, and relatively high mechanical and thermal stability up to 400 deg. C.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19930038731&hterms=hugoniot&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dhugoniot"><span id="translatedtitle"><span class="hlt">Core</span> formation by giant impacts</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tonks, W. B.; Melosh, H. J.</p> <p>1992-01-01</p> <p>The present model for the timing and mechanisms of planetary <span class="hlt">core</span> formation argues that once a planet reaches a certain minimum mass, the large impacts that are typical of late accretion can trigger <span class="hlt">core</span> formation. This model circumvents the difficulties posed by the large-scale segregation of molten iron into diapirs, and the displacement of the cold, elastic interior of the planet by the iron. The analytical <span class="hlt">melting</span> model used is based on the Hugoniot equations, the empirical relationship for the decline of particle velocity with distance, and the linear shock-particle velocity relationship.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/6917971"><span id="translatedtitle">Fire characteristics of <span class="hlt">cored</span> composite materials for marine use</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Nicholas A. Dembsey; Jonathan R. Barnett</p> <p>1998-01-01</p> <p>This paper presents results from Cone Calorimeter testing of two types of <span class="hlt">cored</span> composite materials used in shipbuilding: a GRP\\/Balsa-<span class="hlt">cored</span> sandwich and a GRP\\/PVC foam-<span class="hlt">cored</span> sandwich. The observed phenomena of delamination, <span class="hlt">melting</span> and charring of the <span class="hlt">core</span> materials, and edge effects are discussed in the context of how they affect test results. The “standard” ignition data analysis method specified in</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1208.0493v2"><span id="translatedtitle">Existence of an information unit as a <span class="hlt">postulate</span> of quantum theory</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lluis Masanes; Markus P. Mueller; Remigiusz Augusiak; David Perez-Garcia</p> <p>2013-10-22</p> <p>Does information play a significant role in the foundations of physics? Information is the abstraction that allows us to refer to the states of systems when we choose to ignore the systems themselves. This is only possible in very particular frameworks, like in classical or quantum theory, or more generally, whenever there exists an information unit such that the state of any system can be reversibly encoded in a sufficient number of such units. In this work we show how the abstract formalism of quantum theory can be deduced solely from the existence of an information unit with suitable properties, together with two further natural assumptions: the continuity and reversibility of dynamics, and the possibility of characterizing the state of a composite system by local measurements. This constitutes a new set of <span class="hlt">postulates</span> for quantum theory with a simple and direct physical meaning, like the ones of special relativity or thermodynamics, and it articulates a strong connection between physics and information.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1989LNP...332..408L"><span id="translatedtitle">Fritz Zwicky's <span class="hlt">Postulate</span> of Freedom from Prejudice Considered from the Standpoint of the Theory of Knowledge</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lutz, Markus</p> <p></p> <p>What can we say about unprejudiced thinking as <span class="hlt">postulated</span> by Ritz Zwicky? Freedom from prejudice in opposition to stamped by theory. How does knowledge come about? Through sense perception and thought. The phenomenon is always mediated by organs, respectively by technical instruments. Which conclusion can we draw from this fact? Is the organ of knowledge by which we know nature a part of nature? Can the dialectic materialism explain the processes of human consciousness? What is the fundamental difference between think and perceive? Has human consciousness only a share in nature or also in the spiritual world? The role of the observer in the Copenhagen interpretation. Is the quantum theory applicable to psychic phenomena?</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/799417"><span id="translatedtitle">Estimation of Downstream Cesium Concentrations Following a <span class="hlt">Postulated</span> PAR Pond Dam Break</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chen, K.F.</p> <p>2002-07-08</p> <p>Following a <span class="hlt">postulated</span> PAR Pond dam break, some of the PAR Pond sediment including the cesium could be eroded and be transported downstream to the Savannah River through the Lower Three Runs Creek. Studies showed that most of the eroded sediment including the cesium would deposit in the Lower Three Runs Creek and the remainder would discharge to the Savannah River from the mouth of Lower Three Runs Creek. A WASP5 model was developed to simulate the eroded sediment and cesium transport from the Lower Three Runs Creek mouth to the Atlantic coast. The dissolved cesium concentrations at the Highway 301 bridge and near the City of Savannah Industrial and Domestic Water Supply Plant are 30 and 27 pCi/l, respectively. The concentrations at both locations are less than the U. S. Environmental Protection Agency drinking water standard of 200 pCi/l.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/24062431"><span id="translatedtitle">Existence of an information unit as a <span class="hlt">postulate</span> of quantum theory.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Masanes, Lluís; Müller, Markus P; Augusiak, Remigiusz; Pérez-García, David</p> <p>2013-10-01</p> <p>Does information play a significant role in the foundations of physics? Information is the abstraction that allows us to refer to the states of systems when we choose to ignore the systems themselves. This is only possible in very particular frameworks, like in classical or quantum theory, or more generally, whenever there exists an information unit such that the state of any system can be reversibly encoded in a sufficient number of such units. In this work, we show how the abstract formalism of quantum theory can be deduced solely from the existence of an information unit with suitable properties, together with two further natural assumptions: the continuity and reversibility of dynamics, and the possibility of characterizing the state of a composite system by local measurements. This constitutes a set of <span class="hlt">postulates</span> for quantum theory with a simple and direct physical meaning, like the ones of special relativity or thermodynamics, and it articulates a strong connection between physics and information. PMID:24062431</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.eng.tau.ac.il/~jerby/Jerby_Basalt_Ampere-2013_Proc_PDF.pdf"><span id="translatedtitle">International Conference on Microwave and High Frequency Heating, AMPERE-2013 Nottingham, UK, September 2013 Basalt <span class="hlt">Melting</span> by Localized-Microwave</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Jerby, Eli</p> <p></p> <p>, September 2013 255 Basalt <span class="hlt">Melting</span> by Localized-Microwave Thermal-Runaway Instability E. Jerby*, Y. Meir, M an experimental and theoretical study of the thermal-runaway instability induced by localized microwaves in basalt stones. This effect leads to the inner <span class="hlt">melting</span> of the basalt <span class="hlt">core</span>, and further to its eruption similarly</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.T33D..07S"><span id="translatedtitle">Secular evolution of partial <span class="hlt">melting</span> and <span class="hlt">melt</span> stagnation during the formation of Godzilla Mullion, Philippine Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Snow, J. E.; Ohara, Y.; Harigane, Y.; Michibayashi, K.; Hellebrand, E.; von der Handt, A.; Loocke, M.; Ishii, T.</p> <p>2009-12-01</p> <p>Godzilla Mullion is a large-scale low angle detachment fault (or OCC, Oceanic <span class="hlt">Core</span> Complex) formed during backarc spreading in the Parece Vela Rift behind the Mariana arc system. Detachment spreading occurred during the time interval 15-12 Ma, before the Parece Vela Rift became extinct and the locus of back arc spreading in the system shifted to the East, to the Mariana Trough. During this time, the spreading rate varied from ~70-88 mm/year to zero (at extinction). The decline in the spreading rate, should have had profound effects on the thermal structure of the lithosphere in the rift, including include progressive thickening, decreasing degree of partial <span class="hlt">melting</span>, and increasing <span class="hlt">melt</span> stagnation. We have combined our preliminary data on mantle peridotite mineral chemistry to form a preliminary test of this hypothesis based on mantle peridotites from (currently) 10 sampling stations along the mullion from the cruises CSS33, KR03-01, KH07-02 and YK09-05. This test is for now based primarily on abyssal peridotite spinel chemistry (Dick and Bullen, 1982; Dick 1989). We can distinguish three distinct regions within the mullion based on spinel chemistry: (1) The Distal GM region, including sites KR03-01-D6, KH07-02-D17 and KH07-02-D7. These have a moderately depleted character, with minimum Cr-numbers between 30 and 40, and few samples with high TiO2 (an indicator of <span class="hlt">melt</span> impregnation). (2) The Medial GM region, including stations KH07-02-D6, KR03-01-D7, KH07-02-D21 and YK09-05-6K#1142. These have a more fertile character, with minimum Cr-numbers between 14 and 22, and with the exception of KH07-02-21 (which may belong to the next group) little evidence of <span class="hlt">melt</span> stagnation. (3) The Proximal GM region, including sites KR0301-D9 and D10 and CSS33-D1. These spinels show abundant evidence for <span class="hlt">melt</span> reaction, including plagioclase pseudomorphs (See abstract by Loocke et al., this session) and pervasively elevated TiO2 contents and Cr-numbers in the spinels. We can interpret these variations in the framework of a declining magmatic system as described above. The Distal GM represents the mantle of a robust magmatic system underlying and feeding normal abyssal hill topography to the SW of the GM breakaway. The Medial GM represents mantle that has a lowered <span class="hlt">melt</span> productivity, but has not yet switched from thin-lithospheric, eruptive magmatism to active <span class="hlt">melt</span> stagnation. The proximal GM region represents mantle from near the end of Parece Vela Rift spreading, in which the lithosphere has thickened sufficiently to trap some or most of the <span class="hlt">melts</span> arising from the <span class="hlt">melting</span> zone, resulting in Cr-numbers that are elevated once again along with pervasive TiO2 enrichments thought to be typical of extensive <span class="hlt">melt</span> stagnation.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1987JGR....92.9135C"><span id="translatedtitle">Polar basal <span class="hlt">melting</span> on Mars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clifford, S. M.</p> <p>1987-08-01</p> <p>The potential importance of basal <span class="hlt">melting</span> on Mars is illustrated through the discussion of four examples: (1) the origin of the major polar reentrants, (2) the removal and storage of an ancient Martian ice sheet, (3) the mass balance of the polar terrains, and (4) the possibility of basal <span class="hlt">melting</span> at temperate latitudes. This analysis suggests that the process of basal <span class="hlt">melting</span> may play a key role in understanding the evolution of the Martian polar terrains and the long-term climatic behavior of water on Mars.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=DOE-PATENT-XML&redirectUrl=http://www.osti.gov/doepatents/biblio/867989"><span id="translatedtitle">Nuclear reactor <span class="hlt">melt</span>-retention structure to mitigate direct containment heating</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Tutu, Narinder K. (Manorville, NY); Ginsberg, Theodore (East Setauket, NY); Klages, John R. (Mattituck, NY)</p> <p>1991-01-01</p> <p>A light water nuclear reactor <span class="hlt">melt</span>-retention structure to mitigate the extent of direct containment heating of the reactor containment building. The structure includes a retention chamber for retaining molten <span class="hlt">core</span> material away from the upper regions of the reactor containment building when a severe accident causes the bottom of the pressure vessel of the reactor to fail and discharge such molten material under high pressure through the reactor cavity into the retention chamber. In combination with the <span class="hlt">melt</span>-retention chamber there is provided a passageway that includes molten <span class="hlt">core</span> droplet deflector vanes and has gas vent means in its upper surface, which means are operable to deflect molten <span class="hlt">core</span> droplets into the retention chamber while allowing high pressure steam and gases to be vented into the upper regions of the containment building. A plurality of platforms are mounted within the passageway and the <span class="hlt">melt</span>-retention structure to direct the flow of molten <span class="hlt">core</span> material and help retain it within the <span class="hlt">melt</span>-retention chamber. In addition, ribs are mounted at spaced positions on the floor of the <span class="hlt">melt</span>-retention chamber, and grid means are positioned at the entrance side of the retention chamber. The grid means develop gas back pressure that helps separate the molten <span class="hlt">core</span> droplets from discharged high pressure steam and gases, thereby forcing the steam and gases to vent into the upper regions of the reactor containment building.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2008AGUFM.T42B..05B"><span id="translatedtitle">Postcumulus Processes in Oceanic-Type Olivine-Rich Cumulates: the Role of <span class="hlt">Melt</span> Entrapment vs. <span class="hlt">Melt</span>-Rock Interaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borghini, G.; Rampone, E.</p> <p>2008-12-01</p> <p>Evaluation of postcumulus processes in cumulate rocks can provide insights on the mechanisms and scales of <span class="hlt">melt</span> migration and interaction within the crust, thus contributing to define crustal accretion models. Here we present a microstructural-geochemical study on MORB-type primitive olivine-rich cumulates intruded in the Erro-Tobbio (ET) mantle peridotites (Voltri Massif, Ligurian Alps, Italy), an on-land analogue of (ultra-) slow spreading settings. Postcumulus crystallization is indicated by the occurrence of accessory interstitial minerals (Ti- pargasite, opx , Fe-Ti oxides), and by chemical zoning in intercumulus clinopyroxene related to its textural occurence, i.e. marked REE, Ti, Zr enrichment at almost constant Mg-numbers (88-90) and LREE depletion, from <span class="hlt">core</span> to rim of coarse anhedral clinopyroxene, to thin vermicular cpx grains. Interstitial pargasites have high Nb, Zr, REE contents although preserving "primitive" major element compositions (Mgvalue = 0.86-0.89) and LREE depletion. Significant trace element enrichment at almost constant LREE fractionation in interstitial clinopyroxenes and Ti-rich pargasites argue against the infiltration of exotic evolved <span class="hlt">melts</span> and indicate that interstitial minerals were mainly related to close-system trapped <span class="hlt">melt</span> crystallization. Geochemical modeling shows that crystallization of less than 5% trapped <span class="hlt">melt</span> is sufficient to produce the REE enrichments observed in cpx. The progressive increase in (REE-Zr-Ti) abundances from <span class="hlt">core</span> to rim of large clinopyroxene grains is accounted by an "in-situ" fractional crystallization process. Anomalous Zr enrichment is observed in thin (< 400 µm) interstitial and vermicular clinopyroxenes and pargasitic amphiboles, representing the very last <span class="hlt">melt</span> fraction (reasonably < 2%). At this final crystallization stage, the low residual porosity likely inhibited large-scale <span class="hlt">melt</span> migration. AFC modeling indicates that the high Zr/Nd ratios in cpx could be related to small-scale migration and interaction between residual, evolved, low <span class="hlt">melt</span> fractions and the olivine cumulus matrix, consistent with textural evidence of lobate contacts between vermicular clinopyroxenes and cumulus olivine, indicative of partial olivine resorption. Our study points that small amount of <span class="hlt">melt</span> trapped in an olivine-rich matrix can induce significant trace element enrichment in minerals. Such an evidence argue against large-scale residual <span class="hlt">melt</span> migration, this latter being controlled by porosity and permeability of the crystal mush, and indicates that compaction was very efficient. This could have been favoured by the interplay of different factors, i.e. slow cooling rates and low thermal gradients, and synkinematic deformation (Natland and Dick, 2001, J. V. G. Res, 110, 191-233). The ET cumulates could thus represent the base of a stack of cumulates (3-5 Kb intrusion depth) from which differentiated <span class="hlt">melts</span> migrated upwards and crystallized at shallower lithospheric environments. Overall, this indicates that different <span class="hlt">melt</span> transport and interaction processes may act during crust accretion at very slow spreading settings, e.g. low <span class="hlt">melt</span> fraction entrapment of indigenous <span class="hlt">melts</span> in compaction-dominated deep-seated gabbroic intrusions vs. migration of exotic evolved <span class="hlt">melts</span> through uppermost crustal levels.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/26598631"><span id="translatedtitle">Liquid entrainment by an expanding <span class="hlt">core</span> disruptive accident bubble—a Kelvin\\/Helmholtz phenomenon</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Michael Epstein; Hans K. Fauske; Shigenobu Kubo; Toshio Nakamura; Kazuya Koyama</p> <p>2001-01-01</p> <p>The final stage of a <span class="hlt">postulated</span> energetic <span class="hlt">core</span> disruptive accident (CDA) in a liquid metal fast breeder reactor is believed to involve the expansion of a high-pressure <span class="hlt">core</span>-material bubble against the overlying pool of sodium. Some of the sodium will be entrained by the CDA bubble which may influence the mechanical energy available for damage to the reactor vessel. The</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2007GeCoA..71.3616K"><span id="translatedtitle">Searching for parental kimberlite <span class="hlt">melt</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kopylova, M. G.; Matveev, S.; Raudsepp, M.</p> <p>2007-07-01</p> <p>Constraining the composition of primitive kimberlite magma is not trivial. This study reconstructs a kimberlite <span class="hlt">melt</span> composition using vesicular, quenched kimberlite found at the contact of a thin hypabyssal dyke. We examined the 4 mm selvage of the dyke where the most elongate shapes of the smallest calcite laths suggest the strongest undercooling. The analyzed bulk compositions of several 0.09-1.1 mm 2 areas of the kimberlite free from macrocrysts were considered to be representative of the <span class="hlt">melt</span>. The bulk analyses conducted with a new "chemical point-counting" technique were supplemented by modal estimates, studies of mineral compositions, and FTIR analysis of olivine phenocrysts. The <span class="hlt">melt</span> was estimated to contain 26-29.5 wt% SiO 2, ˜7 wt% of FeO T, 25.7-28.7 wt% MgO, 11.3-15 wt% CaO, 8.3-11.3 wt% CO 2, and 7.6-9.4 wt% H 2O. Like many other estimates of primitive kimberlite magma, the <span class="hlt">melt</span> is too magnesian (Mg# = 0.87) to be in equilibrium with the mantle and thus cannot be primary. The observed dyke contact and the chemistry of the <span class="hlt">melt</span> implies it is highly fluid ( ? = 10 1-10 3 Pa s at 1100-1000 °C) and depolymerized (NBO/T = 2.3-3.2), but entrains with 40-50% of olivine crystals increasing its viscosity. The olivine phenocrysts contain 190-350 ppm of water suggesting crystallization from a low SiO 2 magma ( a below the olivine-orthopyroxene equilibrium) at 30-50 kb. Crystallization continued until the final emplacement at depths of few hundred meters which led to progressively more Ca- and CO 2-rich residual liquids. The <span class="hlt">melt</span> crystallised phlogopite (6-10%), monticellite (replaced by serpentine, ˜10%), calcite rich in Sr, Mg and Fe (19-27%), serpentine (29-31%) and minor amounts of apatite, ulvöspinel-magnetite, picroilmenite and perovskite. The observed content of H 2O can be fully dissolved in the primitive <span class="hlt">melt</span> at pressures greater than 0.8-1.2 kbar, whereas the amount of primary CO 2 in the kimberlite exceeds CO 2 soluble in the primitive kimberlite <span class="hlt">melt</span>. A mechanism for retaining CO 2 in the <span class="hlt">melt</span> may require a separate fluid phase accompanying kimberlite ascent and later dissolution in residual carbonatitic <span class="hlt">melt</span>. Deep fragmentation of the <span class="hlt">melt</span> as a result of volatile supersaturation is not inevitable if kimberlite magma has an opportunity to evolve.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/18562280"><span id="translatedtitle">Evidence for fractional crystallization of wadsleyite and ringwoodite from olivine <span class="hlt">melts</span> in chondrules entrained in shock-<span class="hlt">melt</span> veins.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Miyahara, Masaaki; El Goresy, Ahmed; Ohtani, Eiji; Nagase, Toshiro; Nishijima, Masahiko; Vashaei, Zahra; Ferroir, Tristan; Gillet, Philippe; Dubrovinsky, Leonid; Simionovici, Alexandre</p> <p>2008-06-24</p> <p>Peace River is one of the few shocked members of the L-chondrites clan that contains both high-pressure polymorphs of olivine, ringwoodite and wadsleyite, in diverse textures and settings in fragments entrained in shock-<span class="hlt">melt</span> veins. Among these settings are complete olivine porphyritic chondrules. We encountered few squeezed and flattened olivine porphyritic chondrules entrained in shock-<span class="hlt">melt</span> veins of this meteorite with novel textures and composition. The former chemically unzoned (Fa(24-26)) olivine porphyritic crystals are heavily flattened and display a concentric intergrowth with Mg-rich wadsleyite of a very narrow compositional range (Fa(6)-Fa(10)) in the <span class="hlt">core</span>. Wadsleyite <span class="hlt">core</span> is surrounded by a Mg-poor and chemically stark zoned ringwoodite (Fa(28)-Fa(38)) belt. The wadsleyite-ringwoodite interface denotes a compositional gap of up to 32 mol % fayalite. A transmission electron microscopy study of focused ion beam slices in both regions indicates that the wadsleyite <span class="hlt">core</span> and ringwoodite belt consist of granoblastic-like intergrowth of polygonal crystallites of both ringwoodite and wadsleyite, with wadsleyite crystallites dominating in the <span class="hlt">core</span> and ringwoodite crystallites dominating in the belt. Texture and compositions of both high-pressure polymorphs are strongly suggestive of formation by a fractional crystallization of the olivine <span class="hlt">melt</span> of a narrow composition (Fa(24-26)), starting with Mg-rich wadsleyite followed by the Mg-poor ringwoodite from a shock-induced <span class="hlt">melt</span> of olivine composition (Fa(24-26)). Our findings could erase the possibility of the resulting unrealistic time scales of the high-pressure regime reported recently from other shocked L-6 chondrites. PMID:18562280</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PMC&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2438373"><span id="translatedtitle">Evidence for fractional crystallization of wadsleyite and ringwoodite from olivine <span class="hlt">melts</span> in chondrules entrained in shock-<span class="hlt">melt</span> veins</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Miyahara, Masaaki; El Goresy, Ahmed; Ohtani, Eiji; Nagase, Toshiro; Nishijima, Masahiko; Vashaei, Zahra; Ferroir, Tristan; Gillet, Philippe; Dubrovinsky, Leonid; Simionovici, Alexandre</p> <p>2008-01-01</p> <p>Peace River is one of the few shocked members of the L-chondrites clan that contains both high-pressure polymorphs of olivine, ringwoodite and wadsleyite, in diverse textures and settings in fragments entrained in shock-<span class="hlt">melt</span> veins. Among these settings are complete olivine porphyritic chondrules. We encountered few squeezed and flattened olivine porphyritic chondrules entrained in shock-<span class="hlt">melt</span> veins of this meteorite with novel textures and composition. The former chemically unzoned (Fa24–26) olivine porphyritic crystals are heavily flattened and display a concentric intergrowth with Mg-rich wadsleyite of a very narrow compositional range (Fa6–Fa10) in the <span class="hlt">core</span>. Wadsleyite <span class="hlt">core</span> is surrounded by a Mg-poor and chemically stark zoned ringwoodite (Fa28–Fa38) belt. The wadsleyite–ringwoodite interface denotes a compositional gap of up to 32 mol % fayalite. A transmission electron microscopy study of focused ion beam slices in both regions indicates that the wadsleyite <span class="hlt">core</span> and ringwoodite belt consist of granoblastic-like intergrowth of polygonal crystallites of both ringwoodite and wadsleyite, with wadsleyite crystallites dominating in the <span class="hlt">core</span> and ringwoodite crystallites dominating in the belt. Texture and compositions of both high-pressure polymorphs are strongly suggestive of formation by a fractional crystallization of the olivine <span class="hlt">melt</span> of a narrow composition (Fa24–26), starting with Mg-rich wadsleyite followed by the Mg-poor ringwoodite from a shock-induced <span class="hlt">melt</span> of olivine composition (Fa24–26). Our findings could erase the possibility of the resulting unrealistic time scales of the high-pressure regime reported recently from other shocked L-6 chondrites. PMID:18562280</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/940312"><span id="translatedtitle">Scaleable Clean Aluminum <span class="hlt">Melting</span> Systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Han, Q.; Das, S.K. (Secat, Inc.)</p> <p>2008-02-15</p> <p>The project entitled 'Scaleable Clean Aluminum <span class="hlt">Melting</span> Systems' was a Cooperative Research and Development Agreements (CRADAs) between Oak Ridge National Laboratory (ORNL) and Secat Inc. The three-year project was initially funded for the first year and was then canceled due to funding cuts at the DOE headquarters. The limited funds allowed the research team to visit industrial sites and investigate the status of using immersion heaters for aluminum <span class="hlt">melting</span> applications. Primary concepts were proposed on the design of furnaces using immersion heaters for <span class="hlt">melting</span>. The proposed project can continue if the funding agency resumes the funds to this research. The objective of this project was to develop and demonstrate integrated, retrofitable technologies for clean <span class="hlt">melting</span> systems for aluminum in both the Metal Casting and integrated aluminum processing industries. The scope focused on immersion heating coupled with metal circulation systems that provide significant opportunity for energy savings as well as reduction of <span class="hlt">melt</span> loss in the form of dross. The project aimed at the development and integration of technologies that would enable significant reduction in the energy consumption and environmental impacts of <span class="hlt">melting</span> aluminum through substitution of immersion heating for the conventional radiant burner methods used in reverberatory furnaces. Specifically, the program would couple heater improvements with furnace modeling that would enable cost-effective retrofits to a range of existing furnace sizes, reducing the economic barrier to application.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.2447K"><span id="translatedtitle">Frictional <span class="hlt">melting</span> and stick-slip behavior in volcanic conduits</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kendrick, Jackie Evan; Lavallee, Yan; Hirose, Takehiro; di Toro, Giulio; Hornby, Adrian Jakob; Hess, Kai-Uwe; Dingwell, Donald Bruce</p> <p>2013-04-01</p> <p>Dome-building eruptions have catastrophic potential, with dome collapse leading to devastating pyroclastic flows with almost no precursory warning. During dome growth, the driving forces of the buoyant magma may be superseded by controls along conduit margins; where brittle fracture and sliding can lead to formation of lubricating cataclasite and gouge. Under extreme friction, pseudotachylyte may form at the conduit margin. Understanding the conduit margin processes is vital to understanding the continuation of an eruption and we <span class="hlt">postulate</span> that pseudotachylyte generation could be the underlying cause of stick-slip motion and associated seismic "drumbeats", which are so commonly observed at dome-building volcanoes. This view is supported by field evidence in the form of pseudotachylytes identified in lava dome products at Soufrière Hills (Montserrat) and Mount St. Helens (USA). Both eruptions were characterised by repetitive, periodic seismicity and lava spine extrusion of highly viscous magma. High velocity rotary shear (HVR) experiments demonstrate the propensity for <span class="hlt">melting</span> of the andesitic and dacitic material (from Soufrière Hills and Mount St. Helens respectively) at upper conduit stress conditions (<10 MPa). Starting from room temperature, frictional <span class="hlt">melting</span> of the magmas occurs in under 1 s (<< 1 m) at 1.5 m/s (a speed that is achievable during stick-slip motion). At lower velocities <span class="hlt">melting</span> occurs comparatively later due to dissipation of heat from the slip zone (e.g. 8-15 m at 0.1 m/s). Hence, given the ease with which <span class="hlt">melting</span> is achieved in volcanic rocks, and considering the high ambient temperatures in volcanic conduits, frictional <span class="hlt">melting</span> may thus be an inevitable consequence of viscous magma ascent. The shear resistance of the slip zone during the experiment is also monitored. Frictional <span class="hlt">melting</span> induces a higher resistance to sliding than rock on rock, and viscous processes control the slip zone properties. Variable-rate HVR experiments which mimic rapid velocity fluctuations in stick-slip behavior demonstrate velocity-weakening behavior of <span class="hlt">melt</span>, with a tendency for unstable slip. During ascent, magma may slip and undergo <span class="hlt">melting</span> along the conduit margin. In the process the shear resistance of the slip zone is increased, acting as a viscous brake halting slip (the "stick" of stick-slip motion). Sufficient buoyancy-driven pressures from ascending magma below eventually overcome resistance to produce a rapid slip event (the "slip") along the <span class="hlt">melt</span>-bearing slip zone, which is temporarily lubricated due to velocity-weakening. New magma below experiences the same slip event more slowly (as the magma decompresses) to produce a viscous brake and the process is repeated. This allows a fixed spatial locus that explains the repetitive drumbeat seismicity and the occurrence of "families" of similar seismic events. We conclude that stick-slip motion in volcanic conduits is a self-driving, frictional-<span class="hlt">melt</span>-regulated force common to many dome building volcanoes.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1995Metic..30R.533L"><span id="translatedtitle"><span class="hlt">Core</span> Formation in Asteroid-sized Bodies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Larimer, J. W.</p> <p>1995-09-01</p> <p>Iron meteorites are generally thought to be fragments of asteroid <span class="hlt">cores</span>. The mechanism by which <span class="hlt">cores</span> might form via <span class="hlt">melting</span> and gravitational segregation in internally heated chondritic parent bodies has been modeled. Physical and chemical data drawn from experiments have been used in the modeling. Experimentally determined dihedral angles between silicates and metallic <span class="hlt">melts</span> of appropriate composition are used to understand the fluid dynamics of the process. Experimentally measured distribution coefficients are used to track the variation in composition as the <span class="hlt">cores</span> evolve. In bodies with FeS and FeNi metal contents and S/Fe ratios similar to those observed in E, H and L chondrites, segregation will begin when the temperature at the center reaches the Fe-FeS eutectic, about 1000 degrees C. In a body with less total FeS + metal, such the LL body, or in a body with a S/Fe ratio substantially lower than chondritic, somewhat higher temperatures will be required to initiate segregation because the volume fraction of <span class="hlt">melt</span> will be too small (< 5%) to allow interconnection. When the <span class="hlt">melt</span> becomes interconnected, the segregation process can be described by using Darcy's Law [1]. The rate of <span class="hlt">melt</span> segregation as inferred from either theoretical estimates or experimental observations is sufficiently rapid that segregation will proceed as rapidly as <span class="hlt">melt</span> forms. The rate controlling factor will thus be the rate at which the 1000 degrees C isotherm migrates upward through the body. As the 1000 degrees C isotherm migrates, each increment of new <span class="hlt">melt</span> will have the composition of the eutectic. At greater depths, where the temperature is now higher than the eutectic, larger fractions of FeNi metal will <span class="hlt">melt</span>. Although more metal in the <span class="hlt">melt</span> increases the surface tension, this effect is offset by a temperature effect which simultaneously decreases the surface tension. In addition, since the volume fraction of <span class="hlt">melt</span> with the eutectic composition increases as a function of R^3, the effective <span class="hlt">melting</span> point of the metal + sulfide inside the 1000 degrees C isotherm will approach the eutectic, where the surface tension effects are minimized. The region of the body inside this 1000 degrees C isotherm therefore will be swept clean of its metal as well as its sulfide. References: [1] Turcott D. L. and Schubert G. (1982) Geodynamics.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.V33A2029Z"><span id="translatedtitle">Quantitative characterization of 3-dimensional <span class="hlt">melt</span> distribution in partially molten olivine-basalt aggregates using X-ray synchrotron microtomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhu, W.; Gaetani, G. A.; Fusseis, F.</p> <p>2009-12-01</p> <p>Quantitative knowledge of the distribution of small amounts of silicate <span class="hlt">melt</span> in peridotite and of its influence on permeability are critical to our understanding of <span class="hlt">melt</span> migration and segregation processes in the upper mantle. Estimates for the permeability of partially molten rock require 3D <span class="hlt">melt</span> distribution at the grain-scale. Existing studies of <span class="hlt">melt</span> distribution, carried out on 2D slices through experimental charges, have produced divergent models for <span class="hlt">melt</span> distribution at small <span class="hlt">melt</span> fractions. While some studies conclude that small amounts of <span class="hlt">melt</span> are distributed primarily along triple junctions [e.g., Wark et al., 2003], others predict an important role for <span class="hlt">melt</span> distribution along grain boundaries at low <span class="hlt">melt</span> fractions [e.g., Faul 1997]. Using X-ray synchrotron microtomography, we have obtained the first high quality non-destructive imaging of 3D <span class="hlt">melt</span> distribution in olivine-basalt aggregates. Textually equilibrated partially molten samples consisting of magnesian olivine plus 2, 5, 10, or 20% primitive basalt were synthesized at 1.5 GPa and 1350°C in experiments lasting 264-336 hours. Microtomographic images of <span class="hlt">melt</span> distribution were obtained on cylindrical <span class="hlt">cores</span>, 1 mm in diameter, at a spatial resolution of 1 micron. Textual information such as <span class="hlt">melt</span> channel size, dihedral angle and channel connectivity was then quantified using AVIZO and MATLAB. Our results indicate that as <span class="hlt">melt</span> fraction decreases, <span class="hlt">melt</span> becomes increasingly distributed along 3 grain junctions, in agreement with theoretical predictions. We do not find significant amounts of <span class="hlt">melt</span> along grain boundaries at low <span class="hlt">melt</span> fractions. We found that the true dihedral angle ranges from 50 to 70°, in agreements with results using 2D microcopy. Comparison between the samples provides a quantitative characterization of how <span class="hlt">melt</span> fraction affects <span class="hlt">melt</span> distribution including connectivity. The geometrical data have been incorporated into our network model to obtain macroscale transport properties for partially molten dunite. Results from this tomographic study thus provide constraints on rates of <span class="hlt">melt</span> migration and <span class="hlt">melt</span> extraction within the partially molten regions beneath ocean ridges. Fig 1. <span class="hlt">Melt</span> channels in an olivine-basalt sample with 10 vol% <span class="hlt">melt</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/24027022"><span id="translatedtitle"><span class="hlt">Melting</span> Point, Density, and Reactivity of Metals</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Michael Laing</p> <p>2001-01-01</p> <p>The density and <span class="hlt">melting</span> point of a metal, taken together, can give a useful qualitative guide to the chemical reactivity of the metal. A high density and high <span class="hlt">melting</span> point indicate a low reactivity; conversely, low density and low <span class="hlt">melting</span> point indicate high reactivity. The <span class="hlt">melting</span> point is allied to the heat of sublimation; the density gives a guide to</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://phycomp.technion.ac.il/~phsorkin/thesis/thesis.pdf"><span id="translatedtitle">POINT DEFECTS, LATTICE STRUCTURE AND <span class="hlt">MELTING</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Adler, Joan</p> <p></p> <p>POINT DEFECTS, LATTICE STRUCTURE AND <span class="hlt">MELTING</span> SLAVA SORKIN #12;POINT DEFECTS, LATTICE STRUCTURE) near the <span class="hlt">melting</span> point and this leads to break-down of the long-range crystalline order and <span class="hlt">melting</span> of the mechanism of <span class="hlt">melting</span> transition, and especially to investigate the r^ole of point defects and the surface</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://phycomp.technion.ac.il/~pavelba/Thesis/RelatedFiles/thesis.pdf"><span id="translatedtitle"><span class="hlt">MELTING</span> IN HCP LATTICES PAVEL BAVLI</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Adler, Joan</p> <p></p> <p>- havior of the Gibbs free energy near the <span class="hlt">melting</span> point. . . . . . . . . 4 1.2 A general scheme showing<span class="hlt">MELTING</span> IN HCP LATTICES PAVEL BAVLI #12;<span class="hlt">MELTING</span> IN HCP LATTICES RESEARCH THESIS SUBMITTED IS GRATEFULLY ACKNOWLEDGED #12;Contents Abstract xvii List of symbols 1 1 Introduction 3 2 Bulk <span class="hlt">melting</span> 10 2</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015EGUGA..17.8670V"><span id="translatedtitle">Quantifying <span class="hlt">melting</span> and mobilistaion of interstitial <span class="hlt">melts</span> in crystal mushes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Veksler, Ilya; Dobson, Katherine; Hess, Kai-Uwe; Ertel-Ingrisch, Werner; Humphreys, Madeleine</p> <p>2015-04-01</p> <p>The deformation of crystals mushes and separation of <span class="hlt">melts</span> and crystals in is critical to understanding the development of physical and chemical heterogeneity in magma chambers and has been invoked as an eruption trigger mechanism. Here we investigate the behaviour of the <span class="hlt">melt</span> in the well characterised, classic crystal mush system of the Skaergaard intrusion by combining experimental petrology and the non-destructive 3D imaging methods. Starting materials for partial <span class="hlt">melting</span> experiments were four samples from the upper Middle Zone of the Layered Series. Cylinders, 15 mm in diameter and 20 mm in length, were drilled out of the rock samples, placed in alumina crucibles and held for 5 days in electric furnaces at atmospheric pressure and 1050-1100 °C. Redox conditions set by the CO-CO2 gas mixture were kept close to those of the FMQ buffer. We then use spatially registered 3D x-ray computed tomography images, collected before and after the experiment, to determine the volume and distribution of the crystal framework and interstitial phases, and the volume, distribution and connectivity the interstitial phases that undergo <span class="hlt">melting</span> and extraction while at elevated temperature. Image analysis has allowed us to quantify these physical changes with high spatial resolution. Our work is a first step towards quantitative understanding of the <span class="hlt">melt</span> mobilisation and migration processes operating in notionally locked crystal rich magmatic systems.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2005AGUFM.C51B0298H"><span id="translatedtitle">Digital Imaging of Ice <span class="hlt">Cores</span>: Early Results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hargreaves, G.; McGwire, K.; Taylor, K.; Alley, R. B.; Dupont, T. K.; Reusch, D. B.</p> <p>2005-12-01</p> <p>Ice <span class="hlt">core</span> science addresses fundamental questions of human interest related to global warming, abrupt climate change, biogeochemical cycling and more, and directly informs policymakers. The National Ice <span class="hlt">Core</span> Laboratory (NICL) in Denver, Colorado, is currently developing a high-resolution optical scanning system for laboratory curation in order to expand the accessibility of ice <span class="hlt">core</span> data sets through creation of a digital archive of ice <span class="hlt">core</span> images. Additional goals of this project include development of internet-based search and retrieval capabilities from this digital archive; development of a digital image analysis system specifically for ice <span class="hlt">core</span> studies; integration of digital optical data with other dating methods and testing of the image processing tools in scientific investigations. By providing permanent online digital archives of <span class="hlt">core</span> quality, it will allow improved selection of samples, and documentation of possible <span class="hlt">core</span>-quality artifacts for all U.S. ice <span class="hlt">core</span> scientists. This project will allow any researcher to examine the <span class="hlt">core</span> in similar detail to the few investigators who were fortunate enough to observe it before modifications from sampling and storage. This re-examination can be done decades later by anyone at any location, which is not possible now because only the interpretation of the original observer is recorded. Integration of this digital optical examination into ice <span class="hlt">core</span> analysis will speed discovery, allow collaborative interpretation, and enhance consistency of analysis to improve ice <span class="hlt">core</span> dating, identification of <span class="hlt">melt</span> layers, location of flow disturbances, and more. Here we report on the current status of, and latest results from, these development efforts, including examples of images from the GISP2 (Greenland Ice Sheet Project Two) ice <span class="hlt">core</span>. Preliminary work on this <span class="hlt">core</span> shows that the imaging system successfully and accurately captures numerous features readily recognized by (trained) human observers, such as layering from changes in dust content and seasonal variability, dips and folds (including boudins), and <span class="hlt">melt</span> layers.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19920019348&hterms=solubility&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolubility"><span id="translatedtitle">Experimental determination of the solubility of iridium in silicate <span class="hlt">melts</span>: Preliminary results</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Borisov, Alexander; Dingwell, Donald B.; Oneill, Hugh ST.C.; Palme, Herbert</p> <p>1992-01-01</p> <p>Little is known of the geochemical behavior of iridium. Normally this element is taken to be chalcophile and/or siderophile so that during planetary differentiation processes, e.g., <span class="hlt">core</span> formation, iridium is extracted from silicate phases into metallic phases. Experimental determination of the metal/silicate partition coefficient of iridium is difficult simply because it is so large. Also there are no data on the solubility behavior of iridium in silicate <span class="hlt">melts</span>. With information on the solubility of iridium in silicate <span class="hlt">melts</span> it is possible, in combination with experimental data for Fe-Ir alloys, to calculate the partition coefficient between a metallic phase and a silicate <span class="hlt">melt</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2000JCli...13.4229H"><span id="translatedtitle"><span class="hlt">Postulated</span> Feedbacks of Deciduous Forest Phenology on Seasonal Climate Patterns in the Western Canadian Interior.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hogg, E. H.; Price, D. T.; Black, T. A.</p> <p>2000-12-01</p> <p>A large portion of the western Canadian interior exhibits a distinctive seasonal pattern in long-term mean surface temperatures characterized by anomalously warmer conditions in spring and autumn than would be expected from a sinusoidal model. The anomaly is greatest over the southern boreal forest of western Canada, where trembling aspen (Populus tremuloides Michx.)-a deciduous, broad-leaved species-is an important component. In this region, mean temperatures are 2°-3°C warmer in April and October but nearly 2°C cooler in June and July, relative to a best-fitting sinusoidal function. Another feature of the climate in this region is that average precipitation is low (15-30 mm month1) from October to April but increases sharply during the summer growing season (50-100 mm month1 from June to August). Eddy correlation and sap flow measurements in a boreal aspen forest indicate profound seasonal changes in transpiration and energy partitioning associated with the deciduous nature of the forest canopy. Latent heat (water vapor) flux reaches a maximum during the summer period when leaves are present, while sensible heat flux is highest in early spring when the forest is leafless. Thus, it is <span class="hlt">postulated</span> that feedbacks of leaf phenology of aspen forests, which occupy a large area of the western Canadian interior, may contribute significantly to the distinctive seasonal patterns of mean temperature and precipitation that occur in this region.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/math-ph/0411085v12"><span id="translatedtitle">An Ambiguous Statement Called 'Tetrad <span class="hlt">Postulate</span>' and the Correct Field Equations Satisfied by the Tetrad Fields</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Waldyr A. Rodrigues Jr.; Quintino A. Gomes de Souza</p> <p>2008-01-06</p> <p>The names tetrad, tetrads, cotetrads, have been used with many different meanings in the physical literature, not all of them, equivalent from the mathematical point of view. In this paper we introduce unambiguous definitions for each one of those terms, and show how the old miscellanea made many authors to introduce in their formalism an ambiguous statement called `tetrad <span class="hlt">postulate</span>', which has been source of many misunderstandings, as we show explicitly examining examples found in the literature. Since formulating Einstein's field equations intrinsically in terms of cotetrad fields theta^{a}, a = 0,1,2,3 is an worth enterprise, we derive the equation of motion of each theta^{a} using modern mathematical tools (the Clifford bundle formalism and the theory of the square of the Dirac operator). Indeed, we identify (giving all details and theorems) from the square of the Dirac operator some noticeable mathematical objects, namely, the Ricci, Einstein, covariant D'Alembertian and the Hodge Laplacian operators, which permit to show that each theta^{a} satisfies a well defined wave equation. Also, we present for completeness a detailed derivation of the cotetrad wave equations from a variational principal. We compare the cotetrad wave equation satisfied by each theta^{a} with some others appearing in the literature, and which are unfortunately in error.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/5712896"><span id="translatedtitle">Closed-system <span class="hlt">postulates</span> for predicting waste-package performance in a geological repository</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pigford, T.H.; Chambre, P.L.</p> <p>1986-03-01</p> <p>In a recent paper we reviewed the need for reliable theory and experiment in making long-term predictions of waste performance in a geologic repository. We discussed uncertainties in <span class="hlt">postulated</span> techniques of applying closed-system laboratory leach data to predicting the dissolution of waste solids in a geologic repository, and we discussed the use of mass-transfer analysis to unify theory and experiment and to provide a clear theoretical basis for long-term prediction. Comments on our recent paper by Drs. P.B. Macedo and C.J. Montrose provide a welcome opportunity to clarify several issues related to predicting waste performance. Their comments help illustrate the need for reliable and sound theories for predicting waste performance in the long-term future, and they help focus the fundamental differences between waste dissolution in laboratory leach experiments and dissolution in a repository. To aid better understanding and resolution of the differences between mass transfer in the closed systems considered by Macedo et al. and others and mass transfer in the open systems of waste repositories considered in our mass transfer analysis, we comment here in some detail.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PMC&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2174837"><span id="translatedtitle">Analysis of a Schnute <span class="hlt">postulate</span>-based unified growth mode for model selection in evolutionary computations</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bentil, D.E.; Osei, B.M.; Ellingwood, C.D.; Hoffmann, J.P.</p> <p>2007-01-01</p> <p>In order to evaluate the feasibility of a combined evolutionary algorithm-information theoretic approach to select the best model from a set of candidate invasive species models in ecology, and/or to evolve the most parsimonious model from a suite of competing models by comparing their relative performance, it is prudent to use a unified model that covers a myriad of situations. Using Schnute’s <span class="hlt">postulates</span> as a starting point, we present a single, unified model for growth that can be successfully utilized for model selection in evolutionary computations. Depending on the parameter settings, the unified equation can describe several growth mechanisms. Such a generalized model mechanism, which encompasses a suite of competing models, can be successfully implemented in evolutionary computational algorithms to evolve the most parsimonious model that best fits ground truth data. We have done exactly this by testing the effectiveness of our reaction-diffusion-advection (RDA) model in an evolutionary computation model selection algorithm. The algorithm was validated (with success) against field data sets of the Zebra mussel invasion of Lake Champlain in the United States. PMID:17197072</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFM.V13B2033B"><span id="translatedtitle">Cracks preserve kimberlite <span class="hlt">melt</span> composition</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brett, R. C.; Vigouroux-Caillibot, N.; Donovan, J. J.; Russell, K.</p> <p>2009-12-01</p> <p>The chemical composition of kimberlite <span class="hlt">melts</span> has previously been estimated by measuring aphanitic intrusive rocks (deposit composition) or by partial <span class="hlt">melting</span> experiments on carbonated lherzolites (source composition). Pervasively altered, degassed and contaminated material preclude the determination of the primitive <span class="hlt">melt</span> composition. Here we present data on <span class="hlt">melt</span> compositions trapped in unaltered olivine cracks that have been healed and overgrown prior to shallow level emplacement. During the ascent of kimberlite magma the prograding crack tip samples mantle peridotite xenoliths. Xenoliths rapidly disaggregate over the first few kilometers of transport producing a population of olivine xenocrysts that are released to the fluid-rich <span class="hlt">melt</span>. Rapid ascent of the kimberlite magma causes depressurization and creates internal elastic stresses in the olivine crystals that can only be alleviated by volumetric expansion or brittle failure. On the time scales operative during kimberlite ascent volume expansion is negligible and brittle failure occurs. Small wetting angles between the fluid-rich <span class="hlt">melt</span> and olivine allow infiltration of the <span class="hlt">melt</span> into the crack. These very thin cracks (<5 µm) heal rapidly and preserve primary kimberlitic material en route to the surface. We use the electron microprobe with a focused beam (interaction volume less than 2 µm) to analyze the small volumes of material found in the healed cracks of the olivine. We analyzed for 18 elements including oxygen, which we obtained by utilizing a non-linear time dependent intensity acquisition and empirically determined mass absorption coefficients. By accurately knowing the amount of oxygen in a sample, we assign oxygen molecules to all other analyzed elements (e.g. MgO, Al2O3) and the remaining oxygen is assigned to hydrogen and carbon. The analysis total is used as a constraint on the proportion of each species. Mg/Ca ratios of the cracks vary from 0.6-5 indicating a compositional continuum between alkali-poor, carbonate-rich <span class="hlt">melt</span> and Mg-rich silicate <span class="hlt">melt</span>. OH/CO2 ratios (0-7) and other volatiles (S, F, Cl) are variable and do not correlate with any of the other major elements, consistent with a variably degassed fluid phase. Element associations indicated that Ca, Ni, Ba and Sr co-vary and are inversely related to Mg, Si, Fe, (and several other minor elements). In summary, crack-filling material is Ca and Mg-rich (up to 55 wt.% CaO+MgO), silica-poor (11-32 wt.% SiO2) and are volatile rich ( up to 28 wt.%).</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20000094472&hterms=migration&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmigration"><span id="translatedtitle">Partial <span class="hlt">Melting</span> of the Indarch (EH4) Meteorite : A Textural, Chemical and Phase Relations View of <span class="hlt">Melting</span> and <span class="hlt">Melt</span> Migration</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McCoy, Timothy J.; Dickinson, Tamara L.; Lofgren, Gary E.</p> <p>2000-01-01</p> <p>To Test whether Aubrites can be formed by <span class="hlt">melting</span> of enstatite Chondrites and to understand igneous processes at very low oxygen fugacities, we have conducted partial <span class="hlt">melting</span> experiments on the Indarch (EH4) chondrite at 1000-1500 C. Silicate <span class="hlt">melting</span> begins at 1000 C. Substantial <span class="hlt">melt</span> migration occurs at 1300-1400 C and metal migrates out of the silicate change at 1450 C and approx. 50% silicate partial <span class="hlt">melting</span>. As a group, our experiments contain three immiscible metallic <span class="hlt">melts</span> 9Si-, and C-rich), two immiscible sulfide <span class="hlt">melts</span>(Fe-and FeMgMnCa-rich) and Silicate <span class="hlt">melt</span>. Our partial <span class="hlt">melting</span> experiments on the Indarch (EH4) enstatite Chondrite suggest that igneous processes at low fO2 exhibit serveral unique features. The complete <span class="hlt">melting</span> of sulfides at 1000 C suggest that aubritic sulfides are not relicts. Aubritic oldhamite may have crystallized from Ca and S complexed in the silicate <span class="hlt">melt</span>. Significant metal-sulfide <span class="hlt">melt</span> migration might occur at relatively low degrees of silicate partial <span class="hlt">melting</span>. Substantial elemental exchange occurred between different <span class="hlt">melts</span> (e.g., between sulfide and silicate, Si between silicate and metal), a feature not observed during experiments at higher fO2. This exchange may help explain the formation of aubrites from known enstatite chondrites.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19910012026&hterms=perserverance&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dperserverance"><span id="translatedtitle">Containerless processing of undercooled <span class="hlt">melts</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Perepezko, J. H.</p> <p>1990-01-01</p> <p>All practical solidification processes involve some level of <span class="hlt">melt</span> undercooling. Usually in bulk liquids crystallization is initiated at a heterogeneous nucleation site at low undercooling. The realization of appreciable levels of liquid undercooling requires some control over the kinetics of crystal nucleation. One level of control is available in containerless processing where the capability to <span class="hlt">melt</span> and solidify samples without a container removes a major source of impurities and heterogeneous nucleation sites which can be effective in promoting large undercooling and in studying other potential nucleants. The microgravity environment offers a unique opportunity for containerless processing of large liquid samples with negligible <span class="hlt">melt</span> disturbance and continuous temperature measurement throughout processing. Perhaps the most important potential for microgravity containerless processing lies in the significant structural control to develop distinct microstructures and metastable phases during solidification at high undercooling.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/22106027"><span id="translatedtitle">Westinghouse Small Modular Reactor passive safety system response to <span class="hlt">postulated</span> events</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Smith, M. C.; Wright, R. F. [Westinghouse Electric Company, 600 Cranberry Woods Drive (United States)</p> <p>2012-07-01</p> <p>The Westinghouse Small Modular Reactor (SMR) is an 800 MWt (>225 MWe) integral pressurized water reactor. This paper is part of a series of four describing the design and safety features of the Westinghouse SMR. This paper focuses in particular upon the passive safety features and the safety system response of the Westinghouse SMR. The Westinghouse SMR design incorporates many features to minimize the effects of, and in some cases eliminates the possibility of <span class="hlt">postulated</span> accidents. The small size of the reactor and the low power density limits the potential consequences of an accident relative to a large plant. The integral design eliminates large loop piping, which significantly reduces the flow area of <span class="hlt">postulated</span> loss of coolant accidents (LOCAs). The Westinghouse SMR containment is a high-pressure, compact design that normally operates at a partial vacuum. This facilitates heat removal from the containment during LOCA events. The containment is submerged in water which also aides the heat removal and provides an additional radionuclide filter. The Westinghouse SMR safety system design is passive, is based largely on the passive safety systems used in the AP1000{sup R} reactor, and provides mitigation of all design basis accidents without the need for AC electrical power for a period of seven days. Frequent faults, such as reactivity insertion events and loss of power events, are protected by first shutting down the nuclear reaction by inserting control rods, then providing cold, borated water through a passive, buoyancy-driven flow. Decay heat removal is provided using a layered approach that includes the passive removal of heat by the steam drum and independent passive heat removal system that transfers heat from the primary system to the environment. Less frequent faults such as loss of coolant accidents are mitigated by passive injection of a large quantity of water that is readily available inside containment. An automatic depressurization system is used to reduce the reactor pressure in a controlled manner to facilitate the passive injection. Long-term decay heat removal is accomplished using the passive heat removal systems augmented by heat transfer through the containment vessel to the environment. The passive injection systems are designed so that the fuel remains covered and effectively cooled throughout the event. Like during the frequent faults, the passive systems provide effective cooling without the need for ac power for seven days following the accident. Connections are available to add additional water to indefinitely cool the plant. The response of the safety systems of the Westinghouse SMR to various initiating faults has been examined. Among them, two accidents; an extended station blackout event, and a LOCA event have been evaluated to demonstrate how the plant will remain safe in the unlikely event that either should occur. (authors)</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PMC&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4217094"><span id="translatedtitle">An adult zebrafish model for Laribacter hongkongensis infection: Koch's <span class="hlt">postulates</span> fulfilled</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Xie, Jun; He, Jia-Bei; Shi, Jia-Wei; Xiao, Qiang; Li, Ling; Woo, Patrick CY</p> <p>2014-01-01</p> <p>Laribacter hongkongensis is a gram-negative emerging bacterium associated with invasive bacteremic infections in patients with liver disease and fish-borne community-acquired gastroenteritis and traveler's diarrhea. Although the complete genome of L. hongkongensis has been sequenced, no animal model is available for further study of its pathogenicity mechanisms. In this study, we showed that adult zebrafish infected with L. hongkongensis by immersion following dermal abrasion or intraperitoneal injection suffered mortality in a dose-dependent manner, with lethal dose 50 (LD50) of 2.1×104 and 1.9×104?colony-forming units (CFU)/mL, respectively. All mortalities occurred in the first four days post-infection. Zebrafish that died showed characteristic clinicopathological features: swimming near water surface, marked lethargy and sidestroke; abdominal hemorrhage, ulcers and marked swelling with ascites; and hydropic degeneration and necrosis of hepatocytes around central vein and inflammatory cells infiltration. L. hongkongensis was recovered from the ascitic fluid and tissues of zebrafish that died. Of the 30 zebrafish infected with 2.1×104?CFU/mL (LD50) L. hongkongensis isolated from dead zebrafish using the immersion following dermal abrasion method, 18 (60%) died. All zebrafish that died also showed the characteristic clinical and pathological features. Histopathological studies also showed dilation of hepatic central vein and hydropic degeneration. L. hongkongensis was isolated from the zebrafish that died. The Koch's <span class="hlt">postulates</span> for L. hongkongensis as an infectious agent have been fulfilled. This highly reproducible and effective zebrafish model is of crucial importance for future studies on virulence factors for L. hongkongensis infection. PMID:26038498</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60678072"><span id="translatedtitle">Projecting an energy-efficient California. [Effect of <span class="hlt">postulated</span> program of mandatory conservation standards for buildings and appliances</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>D. B. Goldstein; A. H. Rosenfeld</p> <p>1975-01-01</p> <p>The effects on California electricity consumption of a <span class="hlt">postulated</span> program of mandatory energy conservation standards for building construction and for appliances are calculated. The model sums demands disaggregated by end use in the residential and commercial sectors; for industry a simplified econometric model is used. The potential for growth and conservation is evaluated for each end use, subject to the</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014JOM....66i1612B"><span id="translatedtitle">Challenges in <span class="hlt">Melt</span> Furnace Tests</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Belt, Cynthia</p> <p>2014-09-01</p> <p>Measurement is a critical part of running a cast house. Key performance indicators such as energy intensity, production (or <span class="hlt">melt</span> rate), downtime (or OEE), and <span class="hlt">melt</span> loss must all be understood and monitored on a weekly or monthly basis. Continuous process variables such as bath temperature, flue temperature, and furnace pressure should be used to control the furnace systems along with storing the values in databases for later analysis. While using measurement to track furnace performance over time is important, there is also a time and place for short-term tests.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19930061592&hterms=explosives&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dexplosives"><span id="translatedtitle">Explosive volcanism and the compositions of <span class="hlt">cores</span> of differentiated asteroids</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keil, Klaus; Wilson, Lionel</p> <p>1993-01-01</p> <p>Eleven iron meteorite groups show correlations between Ni and siderophile trace elements that are predictable by distribution coefficients between liquid and solid metal in fractionally crystallizing metal magmas. These meteorites are interpreted to be fragments of the fractionally crystallized <span class="hlt">cores</span> of eleven differentiated asteroids. Many of these groups crystallized from S-depleted magmas which we propose resulted from removal of the first partial <span class="hlt">melt</span> (the Fe,Ni-FeS cotectic <span class="hlt">melt</span>) by explosive pyroclastic volcanism of the type envisaged by Wilson and Keil (1991). We show that these dense, negatively buoyant <span class="hlt">melts</span> can be driven to asteroidal surfaces due to the presence of excess pressure in the <span class="hlt">melt</span> and the presence of buoyant bubbles of gas which decrease the density of the <span class="hlt">melt</span>. We also show that, in typical asteroidal materials, veins will form which grow into dikes and serve as pathways for migration of <span class="hlt">melt</span> and gas to asteroidal surfaces. Since cotectic Fe, Ni-FeS <span class="hlt">melt</span> consists of about 85 wt pct FeS and 15 wt pct Fe, Ni, removal of small volumes of eutectic <span class="hlt">melts</span> results in major loss of S but only minor loss of Fe,Ni, thus leaving sufficient Fe,Ni to form sizeable asteroidal <span class="hlt">cores</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2006JChPh.125s4714S"><span id="translatedtitle">Effective charges along the <span class="hlt">melting</span> line of colloidal crystals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shapran, Larysa; Schöpe, Hans Joachim; Palberg, Thomas</p> <p>2006-11-01</p> <p>The shear modulus G of charged colloidal crystals was measured at several constant particle densities n and varying salt concentrations c up to the <span class="hlt">melting</span> salt concentration cM using torsional resonance spectroscopy. Far from the phase boundary the samples are polycrystalline and the shear modulus stays roughly constant as a function of c. Upon approaching the <span class="hlt">melting</span> transition an increasing amount of wall based crystal material is formed surrounding a shrinking polycrystalline <span class="hlt">core</span> and G drops nearly linearly. When the transition is complete G again stays constant. The morphologic transitions may be scaled upon a single master curve. For the polycrystalline morphology, the elastic data are evaluated in terms of a pairwise additive screened Coulomb interaction yielding a particle effective charge ZG*. Under de-ionized conditions Z0,G* is independent of n and significantly lower than expected from charge renormalization theory. With increasing salt concentration ZG* increases. The increase becomes more pronounced at larger n. By extrapolation we further obtain the <span class="hlt">melting</span> line effective elasticity charge ZM,G*. ZM,G* shows a steplike increase with increasing nM and cM to values consistent with charge renormalization theory. Interestingly, the increase coincides semi-quantitatively with the one expected from the universal <span class="hlt">melting</span> line for charged spheres, thus facilitating a consistent description of phase behavior and elasticity over an extended range of the phase diagram.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013GeoJI.194.1310D"><span id="translatedtitle">Thermal convection in Earth's inner <span class="hlt">core</span> with phase change at its boundary</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Deguen, Renaud; Alboussière, Thierry; Cardin, Philippe</p> <p>2013-09-01</p> <p>Inner <span class="hlt">core</span> translation, with solidification on one hemisphere and <span class="hlt">melting</span> on the other, provides a promising basis for understanding the hemispherical dichotomy of the inner <span class="hlt">core</span>, as well as the anomalous stable layer observed at the base of the outer <span class="hlt">core</span>-the so-called F-layer-which might be sustained by continuous <span class="hlt">melting</span> of inner <span class="hlt">core</span> material. In this paper, we study in details the dynamics of inner <span class="hlt">core</span> thermal convection when dynamically induced <span class="hlt">melting</span> and freezing of the inner <span class="hlt">core</span> boundary (ICB) are taken into account. If the inner <span class="hlt">core</span> is unstably stratified, linear stability analysis and numerical simulations consistently show that the translation mode dominates only if the viscosity ? is large enough, with a critical viscosity value, of order ˜3 × 1018 Pa s, depending on the ability of outer <span class="hlt">core</span> convection to supply or remove the latent heat of <span class="hlt">melting</span> or solidification. If ? is smaller, the dynamic effect of <span class="hlt">melting</span> and freezing is small. Convection takes a more classical form, with a one-cell axisymmetric mode at the onset and chaotic plume convection at large Rayleigh number. ? being poorly known, either mode seems equally possible. We derive analytical expressions for the rates of translation and <span class="hlt">melting</span> for the translation mode, and a scaling theory for high Rayleigh number plume convection. Coupling our dynamic models with a model of inner <span class="hlt">core</span> thermal evolution, we predict the convection mode and <span class="hlt">melting</span> rate as functions of inner <span class="hlt">core</span> age, thermal conductivity, and viscosity. If the inner <span class="hlt">core</span> is indeed in the translation regime, the predicted <span class="hlt">melting</span> rate is high enough, according to Alboussière et al.'s experiments, to allow the formation of a stratified layer above the ICB. In the plume convection regime, the <span class="hlt">melting</span> rate, although smaller than in the translation regime, can still be significant if ? is not too small. Thermal convection requires that a superadiabatic temperature profile is maintained in the inner <span class="hlt">core</span>, which depends on a competition between extraction of the inner <span class="hlt">core</span> internal heat by conduction and cooling at the ICB. Inner <span class="hlt">core</span> thermal convection appears very likely with the low thermal conductivity value proposed by Stacey & Loper, but nearly impossible with the much higher thermal conductivity recently put forward by Sha & Cohen, de Koker et al. and Pozzo et al. We argue however that the formation of an iron-rich layer above the ICB may have a positive feedback on inner <span class="hlt">core</span> convection: it implies that the inner <span class="hlt">core</span> crystallized from an increasingly iron-rich liquid, resulting in an unstable compositional stratification which could drive inner <span class="hlt">core</span> convection, perhaps even if the inner <span class="hlt">core</span> is subadiabatic.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://antoine.frostburg.edu/chem/senese/101/solutions/faq/why-salt-melts-ice.shtml"><span id="translatedtitle">Why does salt <span class="hlt">melt</span> ice?</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p>Fred Senese</p> <p></p> <p>This tutorial on the chemical interaction between salt and ice explains how molecules on the surface of the ice escape into the water (<span class="hlt">melting</span>), and how molecules of water are captured on the surface of the ice (freezing). It was created by the Chemistry Department at Frostburg State University (no, really).</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60348906"><span id="translatedtitle">Batch calcination studies: <span class="hlt">melt</span> formation</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Shefcik</p> <p>1961-01-01</p> <p>It is shown that the formation of a meltable calcine by batch calcination of an acidic waste solution containing primary sodium, iron, and aluminum sulfate and nitrate can be predicted. Calcine <span class="hlt">melting</span> at temperatures less than 900°C can be correlated with the sodium to metal ion ratio and the sulfate to salt nitrate ratio. The minor constituents present in the</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53332098"><span id="translatedtitle">Elongational rheology of polyethylene <span class="hlt">melts</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Bijan Seyfzadeh</p> <p>1999-01-01</p> <p>Elongational <span class="hlt">melt</span> flow behavior is an important and fundamental concept underlying many industrial plastics operations which involve a rapid change of shape as for example fiber spinning and stretching, bottle blow molding, and film blowing and stretching. Under high process loads polymeric materials experience enormous stresses causing the molecular structure to gain considerable orientation. This event has significant effects on</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2010EGUGA..12.8252O"><span id="translatedtitle">Redox viscometry of ferropicrite <span class="hlt">melt</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oryaëlle Chevrel, Magdalena; Potuzak, Marcel; Dingwell, Donald B.; Hess, Kai-Uwe</p> <p>2010-05-01</p> <p>The rheology governs the dynamics of magmas at all scales (i.e. partial <span class="hlt">melting</span>, magmatic chamber emplacement, lava flow behavior). It is also a fundamental constraint on volcanic morphology and landforms. Most terrestrial volcanic flows have moderate iron contents up to 10 wt% but some basalts show contain up to 16 wt%. These ferropicrites range from the Archean to recent, typically forming thin isolated flows near the base of thick lava piles in large igneous provinces, are not well understood. Although ferropicrites are rare on Earth's surface they are believed to be abundant on Mars. Analyses of Martian rocks (from remote sensing data, in situ measurements and meteorite analyses) display up to 20 wt% FeO. Studying these compositions will help to constrain the physical nature and evolution of the volcanism on Mars. The influence of iron on the structure and properties of magmatic <span class="hlt">melts</span>, remains controversial. Simple system investigations indicate an as yet insufficiently parameterized influence of the oxidation state of iron on the rheology and other properties of silicate <span class="hlt">melts</span>. The dependence of shear viscosity on the oxidation state of ferrosilicate <span class="hlt">melts</span> has been measured using the concentric cylinder method and a gas mixing furnace. Previously, two different simple Fe-bearing systems have been studied: (i) anorthite-diopside eutectic composition (AnDi) with variable amount of Fe (up to 20 wt%) as a basalt analog and (ii) sodium disilicate (NS2) with up to 30 wt % Fe. Two natural compositions have been previously investigated, a phonolite and a pantellerite. Here, the compositional range has been extended to the more complex ferropicrite composition using the Adirondack class rock, a typical martian basalt (with low Al content and Fe up to 18,7 wt%). The experimental procedure involves a continuous measurement of viscosity at constant temperature during stepwise reduction state. The <span class="hlt">melt</span> is reduced by flowing CO2 and then successively reducing mixtures of CO2-CO. The composition and oxidation state of the <span class="hlt">melt</span> is monitored by obtaining a <span class="hlt">melt</span> sample after each redox equilibrium step. The <span class="hlt">melts</span> are sampled by dipping an alumina rod into the sample and drawing out a drop of liquid, which is then plunged into water for quenching. The resulting glasses are analyzed by electron microprobe, and the volumetric potassium dichromate titration is employed to determine FeO content. So far we observed a very low viscosity for high iron content samples and a decrease of the viscosity with increasing Fe content. Moreover, the viscosity of all <span class="hlt">melts</span> investigated to date decreases with <span class="hlt">melt</span> reduction. The viscosity decrease is, in general, a nonlinear function of oxidation state expressed as Fe2+/Fetot and can be fitted using logarithmic equation. The range of viscosity is compared to previous experimental studies and will help to understand morphological observations.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2010OptFT..16..399B"><span id="translatedtitle">Advancements in semiconductor <span class="hlt">core</span> optical fiber</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ballato, J.; Hawkins, T.; Foy, P.; Yazgan-Kokuoz, B.; McMillen, C.; Burka, L.; Morris, S.; Stolen, R.; Rice, R.</p> <p>2010-12-01</p> <p>Presented here is a review of recent progress in the nascent field of glass-clad semiconductor <span class="hlt">core</span> optical fibers. Such fibers, generally focused to-date on silicon and germanium <span class="hlt">cores</span>, define a new class of optical fibers that have the potential to significantly advance the fields of nonlinear fiber optics and infrared power delivery. They also can provide considerable insight into the fundamentals of crystal growth and the interplay between thermodynamics and kinetics under non-equilibrium conditions. More specifically, this review begins with a brief history of the international efforts to-date and is followed by a more in-depth discussion of the processing and properties of crystalline unary (silicon and germanium) and binary (indium antimonide) semiconductor optical fibers prepared by a molten <span class="hlt">core</span> approach that enables long lengths at relatively high speeds by comparison to other fabrication methods. Further, the fundamental performance limits are <span class="hlt">postulated</span> as are a range of present and future applications.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/5582000"><span id="translatedtitle">Modeling and database for <span class="hlt">melt</span>-water interfacial heat transfer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Farmer, M.T.; Spencer, B.W. (Argonne National Lab., IL (United States)); Schneider, J.P. (Illinois Univ., Urbana, IL (United States)); Bonomo, B. (Northwestern Univ., Evanston, IL (United States)); Theofanous, G. (California Univ., Berkeley, CA (United States))</p> <p>1992-01-01</p> <p>A mechanistic model is developed to predict the transition superficial gas velocity between bulk cooldown and crust-limited heat transfer regimes in a sparged molten pool with a coolant overlayer. The model has direct applications in the analysis of ex-vessel severe accidents, where molten corium interacts with concrete, thereby producing sparging concrete decomposition gases. The analysis approach embodies thermal, mechanical, and hydrodynamic aspects associated with incipient crust formation at the <span class="hlt">melt</span>/coolant interface. The model is validated against experiment data obtained with water (<span class="hlt">melt</span>) and liquid nitrogen (coolant) simulants. Predictions are then made for the critical gas velocity at which crust formation will occur for <span class="hlt">core</span> material interacting with concrete in the presence of water.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/10136693"><span id="translatedtitle">Modeling and database for <span class="hlt">melt</span>-water interfacial heat transfer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Farmer, M.T.; Spencer, B.W. [Argonne National Lab., IL (United States); Schneider, J.P. [Illinois Univ., Urbana, IL (United States); Bonomo, B. [Northwestern Univ., Evanston, IL (United States); Theofanous, G. [California Univ., Berkeley, CA (United States)</p> <p>1992-04-01</p> <p>A mechanistic model is developed to predict the transition superficial gas velocity between bulk cooldown and crust-limited heat transfer regimes in a sparged molten pool with a coolant overlayer. The model has direct applications in the analysis of ex-vessel severe accidents, where molten corium interacts with concrete, thereby producing sparging concrete decomposition gases. The analysis approach embodies thermal, mechanical, and hydrodynamic aspects associated with incipient crust formation at the <span class="hlt">melt</span>/coolant interface. The model is validated against experiment data obtained with water (<span class="hlt">melt</span>) and liquid nitrogen (coolant) simulants. Predictions are then made for the critical gas velocity at which crust formation will occur for <span class="hlt">core</span> material interacting with concrete in the presence of water.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20000000493&hterms=anorthite&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Danorthite"><span id="translatedtitle">Osmium Solubility in Silicate <span class="hlt">Melts</span>: New Efforts and New Results</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Borisov, A.; Walker, R. J.</p> <p>1998-01-01</p> <p>In a recent paper, Borisov and Palme reported the first experimental results on the partitioning of Os between metal (Ni-rich OsNi alloys) and silicate <span class="hlt">melt</span> of anorthite-diopside eutectic composition at 1400 C and 1 atm total pressure and and at function of O2 from 10(exp -8) to 10(exp -12) atm. Experiments were done by equilibrating OsNi metal loops with silicate <span class="hlt">melt</span>. Metal and glass were analyzed separately by INAA. D(sup 0s) ranged from 10(exp 6) to 10(exp 7), which is inconsistent with <span class="hlt">core</span>/ mantle equilibrium for HSEs and favors the late veneer hypothesis. Unfortunately, there was practically no function of O2 dependence of Os partitioning, and the scatter of experimental results was quite serious, so the formation of Os nuggets was suspected. This new set of experiments was specifically designed to avoid of at least minimize the nugget problem</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013AGUFMPP42A..08A"><span id="translatedtitle">Climate variability, warming and ice <span class="hlt">melt</span> on the Antarctic Peninsula over the last millennium (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abram, N.; Mulvaney, R.; Wolff, E. W.; Triest, J.; Kipfstuhl, S.; Trusel, L. D.; Vimeux, F.; Fleet, L.; Arrowsmith, C.</p> <p>2013-12-01</p> <p>The Antarctic Peninsula has experienced rapid warming over the past 50 years, which has led to extensive summer ice <span class="hlt">melt</span>, the collapse of ice shelves and the acceleration of glacial outflow. But the short observational records of Antarctic climate don't allow for an understanding of how unusual the recent conditions may be. We present reconstructions of temperature and <span class="hlt">melt</span> history since 1000 AD from a highly resolved ice <span class="hlt">core</span> record from James Ross Island on the northeastern Antarctic Peninsula. The spatial pattern of temperature variability across networks of palaeoclimate reconstructions demonstrates that the Southern Annular Mode (SAM) has been an important driver of Antarctic Peninsula climate variability over a range of time scales. Rapid warming of the Antarctic Peninsula since the mid-20th century is consistent with strengthening of the SAM by a combination of greenhouse and later ozone forcing. The rare reconstruction of summer <span class="hlt">melting</span>, from visible <span class="hlt">melt</span> layers in the ice <span class="hlt">core</span>, demonstrates the non-linear response of ice <span class="hlt">melt</span> to increasing summer temperatures. <span class="hlt">Melting</span> in the region is now more intense than at any other time over the last 1000 years and suggests that the Antarctic Peninsula is now particularly susceptible to rapid increases in ice loss in response to relatively small increases in mean temperature.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6475444"><span id="translatedtitle">Liquid jet breakup characterization with application to <span class="hlt">melt</span>-water mixing</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ginsberg, T.</p> <p>1986-01-01</p> <p>Severe accidents in light-water reactors could lead to the flow of molten <span class="hlt">core</span> material from the initial <span class="hlt">core</span> region of the reactor vessel to the lower plenum. Steam explosions have been predicted to occur as a result of the contact of the <span class="hlt">melt</span> with water available in the plenum. It is presently judged by many workers, that the magnitude of the energy released during such an in-vessel explosion would be insufficient to lead to failure of the containment building (SERG, 1985). A major contributing factor in this judgment is that the mass of <span class="hlt">melt</span> which would participate in the interaction would be limited by the quantity of <span class="hlt">melt</span> delivered to the lower plenum to the time of the explosion and by the limited breakup of the molten pour stream as it flows through the plenum prior to the explosion. Limited pour stream breakup would lead to limited <span class="hlt">melt</span>-water mixing and, in addition, to the existence of ''large-scale'' <span class="hlt">melt</span> masses which may lead to very inefficient thermal-to-mechanical energy conversion. The objective of this paper is to assess the available literature relevant to liquid jet breakup and to assess its implications with respect to the behavior of molten corium pour streams as they would flow from the <span class="hlt">core</span> region through the lower plenum. Uncertainties in application of the available literature are discussed. 7 refs., 2 figs.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/22095922"><span id="translatedtitle">Direct writing by way of <span class="hlt">melt</span> electrospinning.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Brown, Toby D; Dalton, Paul D; Hutmacher, Dietmar W</p> <p>2011-12-15</p> <p><span class="hlt">Melt</span> electrospun fibers of poly(?-caprolactone) are accurately deposited using an automated stage as the collector. Matching the translation speed of the collector to the speed of the <span class="hlt">melt</span> electrospinning jet establishes control over the location of fiber deposition. In this sense, <span class="hlt">melt</span> electrospinning writing can be seen to bridge the gap between solution electrospinning and direct writing additive manufacturing processes. PMID:22095922</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/51566253"><span id="translatedtitle">Record summer <span class="hlt">melt</span> in Greenland in 2010</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>M. Tedesco; X. Fettweis; M. R. van den Broeke; C. J. P. P. Smeets; W. J. van de Berg; M. C. Serreze; J. E. Box</p> <p>2011-01-01</p> <p>As Arctic temperatures increase, there is growing concern about the <span class="hlt">melting</span> of the Greenland ice sheet, which reached a new record during the summer of 2010. Understanding the changing surface mass balance of the Greenland ice sheet requires appreciation of the close links among changes in surface air temperature, surface <span class="hlt">melting</span>, albedo, and snow accumulation. Increased <span class="hlt">melting</span> accelerates surface snow</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53073601"><span id="translatedtitle">Surface <span class="hlt">melting</span> on ice shelves and icebergs</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Olga V. Sergienko</p> <p>2005-01-01</p> <p>Disintegration of Larsen Ice Shelf A and B, in 1995 and 2002, respectively, were preceded by two decades of extended summer <span class="hlt">melt</span> seasons and by surface <span class="hlt">melt</span>-water accumulation in ponds, surface crevasses and depressions produced by the elastic flexure of the ice. The extraordinary rapidity of ice-shelf fragmentation into large iceberg plumes following the appearance of surface <span class="hlt">melt</span> water implies</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/47798855"><span id="translatedtitle"><span class="hlt">Melting</span> Point, Boiling Point, and Symmetry</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Robert Abramowitz; Samuel H. Yalkowsky</p> <p>1990-01-01</p> <p>The relationship between the <span class="hlt">melting</span> point of a compound and its chemical structure remains poorly understood. The <span class="hlt">melting</span> point of a compound can be related to certain of its other physical chemical properties. The boiling point of a compound can be determined from additive constitutive properties, but the <span class="hlt">melting</span> point can be estimated only with the aid of nonadditive constitutive</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/48929317"><span id="translatedtitle">Frictional <span class="hlt">melting</span> of peridotite and seismic slip</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>P. Del Gaudio; G. Di Toro; R. Han; T. Hirose; S. Nielsen; T. Shimamoto; A. Cavallo</p> <p>2009-01-01</p> <p>The evolution of the frictional strength along a fault at seismic slip rates (about 1 m\\/s) is a key factor controlling earthquake mechanics. At mantle depths, friction-induced <span class="hlt">melting</span> and <span class="hlt">melt</span> lubrication may influence earthquake slip and seismological data. We report on laboratory experiments designed to investigate dynamic fault strength and frictional <span class="hlt">melting</span> processes in mantle rocks. We performed 20 experiments</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2012AGUFM.V11C2781C"><span id="translatedtitle">Viscosity of Iron-rich Martian Basaltic <span class="hlt">Melts</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chevrel, M. O.; Baratoux, D.; Hess, K.; Dingwell, D. B.</p> <p>2012-12-01</p> <p>Differences in the chemical compositions of planetary mantles can contribute to the large diversity of volcanic <span class="hlt">melts</span>. In particular, differences in oxidation state during <span class="hlt">core</span>-mantle differentiation result in significant variations of iron oxide concentration in the mantle, the most oxidized bodies having the most iron-rich mantles (e.g., Mars). The viscosity of silicate liquids extracted from these mantles is the most important parameter controlling magma ascent and emplacement during eruption. To date, empirical models for prediction of the effect of temperature and composition on the viscosity of silicate <span class="hlt">melts</span> are based on experiments spanning the range of terrestrial compositions of volcanic rocks. This study extends the capability of those models to predict the viscosity of <span class="hlt">melts</span> with iron-rich Martian compositions (up to 20 wt.% FeO). The investigated compositions comprise the in-situ analysed Adirondack, Backstay and Irvine rocks (Gusev crater, Mars) and two compositions representing respectively the Amazonian volcanism and Hesperian volcanism (Baratoux et al., 2011). The dry viscosity at high temperature was determined via the concentric cylinder method in air and under reduced conditions and the low temperature viscosities were estimated from the glass transition temperature determined with a differential scanning calorimeter. The investigation of iron-rich Martian <span class="hlt">melt</span> viscosity is experimentally challenging because of liquid-liquid immiscibility and rapid crystallisation during quenching. The viscosity values at high temperatures are as low as for lunar basalts and under-saturated terrestrial rocks and are affected by the iron redox state. Viscosities of supercooled <span class="hlt">melts</span> show significant discrepancies to existing models possibly resulting from the effect of iron-oxidation state on glass transition temperature.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.3419H"><span id="translatedtitle">Experimental investigation of stress-driven <span class="hlt">melt</span> segregation and electrical conductivity of partially molten mantle rocks with low carbonated <span class="hlt">melt</span> fractions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hashim, Leila; Gaillard, Fabrice; Gardes, Emmanuel; Scaillet, Bruno</p> <p>2013-04-01</p> <p>The mechanical and thermal properties of the mantle are of prime concern since they play a major part in Earth's global geodynamics such as mantle convection, crustal flow and plate shifting. Several magnetotelluric and seismic campaigns, such as the <span class="hlt">MELT</span> experiment, have shown high conductivity and low velocity zones that can be interpreted in terms of partial <span class="hlt">melting</span>. Depending on the geological context, interactions between partial <span class="hlt">melting</span>, deformation and <span class="hlt">melt</span>-rock reactions can influence the nature of the produced <span class="hlt">melt</span> and its segregation from the host rock. Recent experimental studies have shown that the high conductivity zones beneath mid-ocean ridges are best explained by low carbonated <span class="hlt">melt</span> fractions (< 1 wt.%). Although recent experimental and theoretical studies have shown that shear stress gradients in initially homogeneous basaltic <span class="hlt">melt</span>-bearing aggregates promote <span class="hlt">melt</span> redistribution (Takei and Holtzman, 2009; Caricchi et al., 2011), little is known on the impact of shear stress gradients in samples containing less than 1 wt. % carbonated <span class="hlt">melts</span>. All these studies lead to unanswered questions: how do these gradients influence <span class="hlt">melt</span> mobility and therefore <span class="hlt">melt</span> interconnectivity in partially molten samples with < 1 wt. % <span class="hlt">melt</span>? How do low <span class="hlt">melt</span> fractions impact on physical properties such as the bulk viscosity of partially molten rocks, on the deformation regime? How does <span class="hlt">melt</span> segregation resulting from an applied shear stress impact on electrical and seismic anisotropy? To answer these questions, we have synthesized by spark plasma sintering large volume samples of forsterite and enstatite aggregates containing an initial homogeneous distribution of Na-rich carbonated <span class="hlt">melts</span> (1 wt. %), which will be deformed under torsion in an internally heated Paterson-type apparatus coupled to an impedance spectrometer. These experiments will enable us to directly measure the bulk viscosity of these partially molten samples as well as collect continuous electrical measurements during deformation. We will similarly investigate carbonated <span class="hlt">melt</span> migration velocities by deforming samples under torsion in a source/sink geometry. The source consisting of Na-rich carbonated <span class="hlt">melt</span>, which will form the inner <span class="hlt">core</span>, will be coupled with a nominally <span class="hlt">melt</span>-free sink of forsterite and enstatite forming the outer ring. Our novel approach consisting in an internally coherent set of petrological-geophysical-rheological constraints will enable us to better interpret the anomalies detected by geophysical probing beneath mid-ocean ridges. Takei, Y., Holtzman, B., 2009. Viscous constitutive relations of solid-liquid composites in terms of grain boundary contiguity: 3. Causes and consequences of viscous anisotropy, J. Geophys. Res. 114, B06207, doi:10.1029/2008JB005852. Caricchi, L., Gaillard, F., Mecklenburgh, J., Le Trong, E., 2011. Experimental determination of electrical conductivity during deformation of <span class="hlt">melt</span>-bearing olivine aggregates: Implications for electrical anisotropy in the oceanic low velocity zone. Earth Planet. Sci. Lett. 302, 81-94.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2004AGUFM.V51D..05G"><span id="translatedtitle">Models for silicate <span class="hlt">melt</span> viscosity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Giordano, D.; Russell, K.; Moretti, R.; Mangiacapra, A.; Potuzak, M.; Romano, C.; Dingwell, D. B.</p> <p>2004-12-01</p> <p>The prediction of viscosity in silicate liquids, over the range of temperatures and compositions encountered in nature, remains one of the most challenging and elusive goals in Earth Sciences. Recent work has demonstrated that there are now sufficient experimental measurements of <span class="hlt">melt</span> viscosity to create new viscosity models to replace previous Arrhenian models [1],[2] and extend the compositional range of more recent non-Arrhenian models [3]. Most recently, [4] have developed an empirical strategy for accurately predicting viscosities over a very wide range of anhydrous silicate <span class="hlt">melt</span> compositions (e.g., rhyolite to basanite). Future models that improve upon this work, will probably extend the composition range of the model to consider, at least, H2O and other volatile components and may utilize a compositional basis that reflects <span class="hlt">melt</span> structure. In preparation for the next generation model, we explore the attributes of the three most common equations that could be used to model the non-Arrhenian viscosity of multicomponent silicate <span class="hlt">melts</span>. The equations for the non-Arrhenian temperature dependence of viscosity (? ) include: a) Vogel-Fulcher-Tammann (VFT): log ? = A + B/(T - C) b) Adam and Gibbs (AG): log ? = A + B/[T log (T/C)], and c) Avramov (Av): log ? = A + [B/T]? We use an experimental database of approximately 900 high-quality viscosity measurements on silicate <span class="hlt">melts</span> to test the ability of each equation to capture the experimental data. These equations have different merits [5]. VFT is purely empirical in nature. The AG model has a quasi-theoretical basis that links macroscopic transport properties directly to thermodynamic properties via the configurational entropy. Lastly, the model proposed by Avramov adopts a form designed to relate the fit parameter (? ) to the fragility of the <span class="hlt">melt</span>. [1] Shaw, H.R., 1972. Am J Science, 272, 438-475. [2] Bottinga Y. and Weill, D., 1972. Am J Science, 272, 438-475. [3] Hess, K.U. and Dingwell, D.B, 1996, Am Min, 81, 1297-1300. [4] D. Giordano & D.B. Dingwell, 2003. EPSL. 208, 337 (and related corrige EPSL 221, 449) [5] J.K. Russell, D. Giordano & D.B. Dingwell, 2003. Am Min 88, 1390</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015Sci...347..418M"><span id="translatedtitle">Shock compression of stishovite and <span class="hlt">melting</span> of silica at planetary interior conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Millot, M.; Dubrovinskaia, N.; ?ernok, A.; Blaha, S.; Dubrovinsky, L.; Braun, D. G.; Celliers, P. M.; Collins, G. W.; Eggert, J. H.; Jeanloz, R.</p> <p>2015-01-01</p> <p>Deep inside planets, extreme density, pressure, and temperature strongly modify the properties of the constituent materials. In particular, how much heat solids can sustain before <span class="hlt">melting</span> under pressure is key to determining a planet’s internal structure and evolution. We report laser-driven shock experiments on fused silica, ?-quartz, and stishovite yielding equation-of-state and electronic conductivity data at unprecedented conditions and showing that the <span class="hlt">melting</span> temperature of SiO2 rises to 8300 K at a pressure of 500 gigapascals, comparable to the <span class="hlt">core</span>-mantle boundary conditions for a 5–Earth mass super-Earth. We show that mantle silicates and <span class="hlt">core</span> metal have comparable <span class="hlt">melting</span> temperatures above 500 to 700 gigapascals, which could favor long-lived magma oceans for large terrestrial planets with implications for planetary magnetic-field generation in silicate magma layers deep inside such planets.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/25613887"><span id="translatedtitle">Planetary science. Shock compression of stishovite and <span class="hlt">melting</span> of silica at planetary interior conditions.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Millot, M; Dubrovinskaia, N; ?ernok, A; Blaha, S; Dubrovinsky, L; Braun, D G; Celliers, P M; Collins, G W; Eggert, J H; Jeanloz, R</p> <p>2015-01-23</p> <p>Deep inside planets, extreme density, pressure, and temperature strongly modify the properties of the constituent materials. In particular, how much heat solids can sustain before <span class="hlt">melting</span> under pressure is key to determining a planet's internal structure and evolution. We report laser-driven shock experiments on fused silica, ?-quartz, and stishovite yielding equation-of-state and electronic conductivity data at unprecedented conditions and showing that the <span class="hlt">melting</span> temperature of SiO2 rises to 8300 K at a pressure of 500 gigapascals, comparable to the <span class="hlt">core</span>-mantle boundary conditions for a 5-Earth mass super-Earth. We show that mantle silicates and <span class="hlt">core</span> metal have comparable <span class="hlt">melting</span> temperatures above 500 to 700 gigapascals, which could favor long-lived magma oceans for large terrestrial planets with implications for planetary magnetic-field generation in silicate magma layers deep inside such planets. PMID:25613887</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/19906731"><span id="translatedtitle">The Invariant Set <span class="hlt">Postulate</span>: a new geometric framework for the foundations of quantum theory and the role played by gravity</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>T. N. Palmer</p> <p>2009-01-01</p> <p>A new law of physics is proposed, defined on the cosmological scale but with\\u000asignificant implications for the microscale. Motivated by nonlinear dynamical\\u000asystems theory and black-hole thermodynamics, the Invariant Set <span class="hlt">Postulate</span>\\u000aproposes that cosmological states of physical reality belong to a\\u000anon-computable fractal state-space geometry I, invariant under the action of\\u000asome subordinate deterministic causal dynamics. An exploratory analysis</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/56485867"><span id="translatedtitle">The Invariant Set <span class="hlt">Postulate</span>: a new geometric framework for the foundations of quantum theory and the role played by gravity</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>T. N. Palmer</p> <p>2009-01-01</p> <p>A new law of physics is proposed, defined on the cosmological scale but with significant implications for the microscale. Motivated by nonlinear dynamical systems theory and black-hole thermodynamics, the Invariant Set <span class="hlt">Postulate</span> proposes that cosmological states of physical reality belong to a non-computable fractal state-space geometry I, invariant under the action of some subordinate deterministic causal dynamics. An exploratory analysis</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://www.apsnet.org/edcenter/k-12/teachersguide/brownrot/Pages/default.aspx"><span id="translatedtitle">Who Done It? Or what's that brown fuzzy stuff on my plum? (Koch's <span class="hlt">Postulates</span> for Proof of Pathogenicity)</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p>Claudia A. Jasalavich (Nashua, NH; )</p> <p>2001-11-28</p> <p>This resource demonstrates how plant pathologists and microbiologists determine what pathogens cause disease in plants or animals. In this lab students will learn about Kochs <span class="hlt">Postulates</span>, the critical steps used to prove that a particular microbe is the cause of a specific disease in a host organism (plant or animal). This lesson is suitable for grades 7-12 and does not require the purchase or maintenance of special cultures. A simplified exercise, without cultures, to demonstrate the Germ Theory also is described.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/20854190"><span id="translatedtitle">Assessment of the Environmental Impact of Tritium Release from Wolsong Tritium Removal Facility at the <span class="hlt">Postulated</span> Accident</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yook, Daesik [Korea Advanced Institute of Science and Technology (Korea, Republic of); Lee, KunJai [Korea Advanced Institute of Science and Technology (Korea, Republic of); Chung, Hongsuk [Korea Atomic Energy Research Institute (Korea, Republic of)</p> <p>2005-07-15</p> <p>In Korea, Wolsong Tritium Removal Facility (WTRF) is scheduled to begin operation in 2005 to reduce the amount of tritium generated in the moderator and coolant. The objective of this study is to evaluate the environmental impact of tritium released from WTRF in the <span class="hlt">postulated</span> accident. In order to achieve this, a computer code was developed at KAIST (Korea Advanced Institute of Science and Technology). This code can be used to evaluate the individual and public dose with the source term. This source term can represent not only the concentration of tritium that will be stored at the long term tritium storage vault located in the underground of WTRF building but also may be released to the environment from the WTRF online system by variously <span class="hlt">postulated</span> accidents. To validate this code, calculated results were compared with the previous reference under the same assumption. Even if the most severe <span class="hlt">postulated</span> accident that the tritium may be released through the fracture of the storage vault was occurred, the result of individual dose at the exclusion area boundary is turned out to be within the radiation dose limit.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/119875"><span id="translatedtitle">Ferrocyanide Safety Program: Analysis of <span class="hlt">postulated</span> energetic reactions and resultant aerosol generation in Hanford Site Waste Tanks</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Postma, A.K. [G and P Consulting, Inc., Dallas, OR (United States); Dickinson, D.R. [Westinghouse Hanford Co., Richland, WA (United States)</p> <p>1995-09-01</p> <p>This report reviews work done to estimate the possible consequences of <span class="hlt">postulated</span> energetic reactions in ferrocyanide waste stored in underground tanks at the Hanford Site. The issue of explosive reactions was raised in the 1987 Environmental Impact Statement (EIS), where a detonation-like explosion was <span class="hlt">postulated</span> for the purpose of defining an upper bound on dose consequences for various disposal options. A review of the explosion scenario by the General Accounting Office (GAO) indicated that the aerosol generation and consequent radioactive doses projected for the explosion <span class="hlt">postulated</span> in the EIS were understated by one to two orders of magnitude. The US DOE has sponsored an extensive study of the hazard posed by uncontrolled exothermic reactions in ferrocyanide waste, and results obtained during the past three years have allowed this hazard to be more realistically assessed. The objective of this report is to summarize the improved knowledge base that now indicates that explosive or vigorous chemical reactions are not credible in the ferrocyanide waste stored in underground tanks. This improved understanding supports the decision not to proceed with further analyses or predictions of the consequences of such an event or with aerosol tests in support of such predictions. 53 refs., 2 tabs.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015EGUGA..17.6674D"><span id="translatedtitle">Double-diffusive inner <span class="hlt">core</span> translation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Deguen, Renaud; Alboussière, Thierry; Labrosse, Stéphane</p> <p>2015-04-01</p> <p>The hemispherical asymmetry of the inner <span class="hlt">core</span> has recently been interpreted as resulting form a high-viscosity mode of inner <span class="hlt">core</span> convection, consisting in a translation of the inner <span class="hlt">core</span>. With <span class="hlt">melting</span> on one hemisphere and crystallization on the other one, inner <span class="hlt">core</span> translation would impose a strongly asymmetric buoyancy flux at the bottom of the outer <span class="hlt">core</span>, with likely strong implications for the dynamics of the outer <span class="hlt">core</span> and the geodynamo. The main requirement for convective instability in the inner <span class="hlt">core</span> is an adverse radial density gradient. While older estimates of the inner <span class="hlt">core</span> thermal conductivity favored a superadiabatic temperature gradient and the existence of thermal convection, the much higher values recently proposed make thermal convection unlikely. Compositional convection might be a viable alternative to thermal convection: an unstable compositional gradient may arise in the inner <span class="hlt">core</span> either because the light elements present in the <span class="hlt">core</span> are predicted to become increasingly incompatible as the inner <span class="hlt">core</span> grows (Gubbins et al. 2013), or because of a possibly positive feedback of the development of the F-layer on inner <span class="hlt">core</span> convection. Though the magnitude of the destabilizing effect of the compositional field is predicted to be similar to or smaller than the stabilizing effect of the thermal field, the huge difference between thermal and chemical diffusivities implies that double-diffusive instabilities may still arise even if the net density decreases upward. We propose here a theoretical (linear stability analysis) and numerical study of double diffusive convection in the inner <span class="hlt">core</span>, focusing on the translation mode, and discuss in what conditions inner <span class="hlt">core</span> translation can develop.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/5138100"><span id="translatedtitle">Formation and characterization of fission-product aerosols under <span class="hlt">postulated</span> HTGR accident conditions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tang, I.N.; Munkelwitz, H.R.</p> <p>1982-07-01</p> <p>The paper presents the results of an experimental investigation on the formation mechanism and physical characterization of simulated nuclear aerosols that could likely be released during an HTGR <span class="hlt">core</span> heat-up accident. Experiments were carried out in a high-temperature flow system consisting essentially of an inductively heated release source, a vapor deposition tube, and a filter assembly for collecting particulate matter. Simulated fission products Sr and Ba as oxides are separately impregnated in H451 graphite wafers and released at elevated temperatures into a dry helium flow. In the presence of graphite, the oxides are quantitatively reduced to metals, which subsequently vaporize at temperatures much lower than required for the oxides alone to vaporize in the absence of graphite. A substantial fraction of the released material is associated with particulate matter, which is collected on filters located downstream at ambient temperature. The release and transport of simulated fission product Ag as metal are also investigated.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/21067376"><span id="translatedtitle"><span class="hlt">Melting</span> And Purification Of Niobium</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Salles Moura, Hernane R.; Moura, Lourenco de [CBMM - Companhia Brasileira de Metalurgia e Mineracao, Fazenda Corrego da Mata, P.O. BOX 8, 38.183.903 - Araxa, MG (Brazil)</p> <p>2007-08-09</p> <p>The aspects involved in the purification of niobium in Electron Beam Furnaces will be outlined and correlated with practical experience accumulated over 17 years of continuously producing high purity niobium metal and niobium-zirconium ingots at CBMM, meeting the needs for a wide range of uses. This paper also reports some comments regarding raw material requirements, the experience on cold hearth operation <span class="hlt">melting</span> niobium and the production of large grains niobium ingots by CBMM with some comments of their main characteristics.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFMDI13B4271F"><span id="translatedtitle">Lower Mantle <span class="hlt">melting</span> model and it's geodynamical applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fomin, I.; Tackley, P. J.</p> <p>2014-12-01</p> <p>Model of solid-liquid equilibrium laws and substances properties in lower mantle conditions is important to understand the early stages of evolution of terrestrial planets, such as <span class="hlt">core</span> formation and magma ocean crystallization. This model is also necessary to prove theories on some modern seismic features of the Earth (e.g. ultra-low velocity zones) and petrological observations (e.g. lower mantle mineral assemblage inclusions in diamonds). Numerous experimental and numerical studies of the lower mantle phases provide sufficient amount of data to build up a thermodynamic model, which can be used in geophysical fluid dynamics research. Experimental studies are the direct source of soliduses values, but other thermodynamic parameters stay unclear. Molecular Dynamics modeling provides data on thermodynamic properties of solids and liquids (density, heat capacity, latent heat of <span class="hlt">melting</span> etc.). But absence of minor components (iron, alkali etc.) and some numerical issues (e.g. [Belonoshko, 2001]) make it to overestimate <span class="hlt">melting</span> temperatures significantly (up to 20-30%). Our approach is to develop a model based on MD data by [de Koker et al., 2013] with evaluation of all important parameters according to classical thermodynamic equations. But <span class="hlt">melting</span> temperatures (especially at eutectic points) are corrected along Clausius-Clapeyron slopes to agree with modern experimental data ([Andrault et al., 2011], [Andrault et al., 2014], [Fiquet et al., 2010], [Hirose et al., 1999], [Mosenfelder et al., 2007], [Nomura et al., 2014],[Ozawa et al., 2011], [Zerr et al., 1998]). Notable effect on <span class="hlt">melt</span> and solid densities has iron partitioning, so KD value reported by [Andrault et al., 2012] was used. Proposed model was implemented into StagYY software (e.g. [Tackley, 2008]). It is a finite-volume discretization code for advection of solid and liquid in a planetary scale. CMB temperature was set to be 4000-4400 K. Calculations predict appearing and disappearing batches containing up to 5-7% of <span class="hlt">melt</span>. Amount of FeO in liquid is up to 18%, so <span class="hlt">melts</span> are 2 % denser than solid counterpart, resulting in total density increase up to 1 %. This data fits properties proposed for Ultra-Low Velocity Zones (<span class="hlt">melt</span> fraction between 5 and 30 % [Garnero et al., 1998], and density increase of at least 1% [Beuchert & Schmeling, 2013]).</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015EGUGA..1714372F"><span id="translatedtitle">Deep mantle <span class="hlt">melting</span>-solidifying and produced heterogeneities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fomin, Ilya; Tackley, Paul</p> <p>2015-04-01</p> <p>Model for solid-liquid equilibrium and substance properties in lower mantle conditions is important to understand the early stages of evolution of terrestrial planets, such as <span class="hlt">core</span> formation and magma ocean crystallization. This model is also necessary to prove theories on some modern seismic features of the Earth (e.g. ultra-low velocity zones) and petrological observations (e.g. lower mantle mineral assemblage inclusions in diamonds). Numerous experimental and numerical studies of the lower mantle phases provide sufficient amount of data to build up a thermodynamic model, which can be used in geophysical fluid dynamics research. Molecular Dynamics modeling provides data on thermodynamic properties of solids and liquids (density, heat capacity, thermal expansion, latent heat of <span class="hlt">melting</span> etc.). Absence of minor components (iron, alkali etc.) makes it to overestimate <span class="hlt">melting</span> temperatures significantly (up to 20-30%), so experimental data are also very important. Our model is based on MD data by [de Koker et al., 2013] with evaluation of all important parameters according to classical thermodynamic equations. <span class="hlt">Melting</span> temperatures (especially at eutectic points) are corrected along Clausius-Clapeyron slopes to agree with modern experimental data ([Andrault et al., 2011], [Andrault et al., 2014], [Fiquet et al., 2010], [Hirose et al., 1999], [Mosenfelder et al., 2007], [Nomura et al., 2014], [Ozawa et al., 2011], [Zerr et al., 1998]). KD value for iron reported by [Andrault et al., 2012] was used. Proposed model was implemented into StagYY software (e.g. [Tackley, 2008]). It is a finite-volume discretization code for advection of solid and liquid in a planetary scale. A principal new feature of the used code modification is that we use separated variables for chemical compounds: SiO2, FeO, MgO and other (list can be extended). So it is possible to trace mantle heterogeneities produced by <span class="hlt">melting</span> and solidifying events. Calculations predict appearing and disappearing batches containing up to 5-7% of <span class="hlt">melt</span> (CMB temperature 4000-4400 K). Amount of FeO in liquid is up to 18%, so <span class="hlt">melts</span> are 2 % denser than solid counterpart, resulting in total density increase up to 1 %. This data fits properties proposed for Ultra-Low Velocity Zones (<span class="hlt">melt</span> fraction between 5 and 30 % [Garnero et al., 1998], and density increase of at least 1% [Beuchert & Schmeling, 2013]).</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60143330"><span id="translatedtitle">An assessment of the radiological doses resulting from accidental uranium aerosol releases and fission product releases from a <span class="hlt">postulated</span> criticality accident at the Oak Ridge Y-12 Plant</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>S. E. Fisher; K. E. Lenox</p> <p>1995-01-01</p> <p>A dose assessment for two separate normalized source terms was conducted for the Oak Ridge Y-12 Plant. The first source term consisted of the noble gas and iodine fission products emanating from a <span class="hlt">postulated</span> criticality with a magnitude of 10¹⁹ fissions. The second <span class="hlt">postulated</span> source term was 1 kg of respirable highly enriched uranium. The MELCOR Accident Consequence Code System</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2009APS..MARL40015S"><span id="translatedtitle">Supercoil Formation During DNA <span class="hlt">Melting</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sayar, Mehmet; Avsaroglu, Baris; Kabakcioglu, Alkan</p> <p>2009-03-01</p> <p>Supercoil formation plays a key role in determining the structure-function relationship in DNA. Biological and technological processes, such as protein synthesis, polymerase chain reaction, and microarrays relys on separation of the two strands in DNA, which is coupled to the unwinding of the supercoiled structure. This problem has been studied theoretically via Peyrard-Bishop and Poland-Scheraga type models, which include a simple representation of the DNA structural properties. In recent years, computational models, which provide a more realtistic representaion of DNA molecule, have been used to study the <span class="hlt">melting</span> behavior of short DNA chains. Here, we will present a new coarse-grained model of DNA which is capable of simulating sufficiently long DNA chains for studying the supercoil formation during <span class="hlt">melting</span>, without sacrificing the local structural properties. Our coarse-grained model successfully reproduces the local geometry of the DNA molecule, such as the 3'-5' directionality, major-minor groove structure, and the helical pitch. We will present our initial results on the dynamics of supercoiling during DNA <span class="hlt">melting</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19870036182&hterms=Melting+point&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3D%2528Melting%2Bpoint%2529"><span id="translatedtitle">Small particle <span class="hlt">melting</span> of pure metals</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Allen, G. L.; Bayles, R. A.; Gile, W. W.; Jesser, W. A.</p> <p>1986-01-01</p> <p>Submicron-sized crystallites of lead, tin, indium and bismuth were <span class="hlt">melted</span> in situ in the modified specimen chamber of a Siemens transmission e lectron microscope. <span class="hlt">Melting</span> point and size determinations were made directly from the dark field images of the crystallites. Particles exhibited <span class="hlt">melting</span> points that decreased with decreasing particle size. A near-linear relationship was observed for the <span class="hlt">melting</span> point as a function of the reciprocal of the radius. Thermodynamnic expressions based on the significant contributions of the surface energy to the free energy of the system also suggest a linear relation. Other factors, such as shape and surface contamination, were also observed to affect the size-dependent <span class="hlt">melting</span> of particles. Crystallites of extended platelet shape did not exhibit a significant depression in <span class="hlt">melting</span> point. Elevated residual gas pressures were found to lessen the <span class="hlt">melting</span> point depression of spherical particles.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/22282643"><span id="translatedtitle">String <span class="hlt">melting</span> in a photon bath</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Karouby, Johanna, E-mail: karoubyj@mit.edu [Center for Theoretical Physics and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachussetts 02139 (United States)</p> <p>2013-10-01</p> <p>We compute the decay rate of a metastable cosmic string in contact with a thermal bath by finding the instanton solution. The new feature is that this decay rate is found in the context of non thermal scalar fields in contact with a thermal bath of photons. In general, to make topologically unstable strings stable, one can couple them to such a bath. The resulting plasma effect creates metastable configurations which can decay from the false vacuum to the true vacuum. In our specific set-up, the instanton computation is realized for the case of two out-of-equilibrium complex scalar fields: one is charged and coupled to the photon field, and the other is neutral. New effects coming from the thermal bath of photons make the radius of the nucleated bubble and most of the relevant physical quantities temperature-dependent. However, the temperature appears in a different way than in the purely thermal case, where all scalar fields are in thermal equilibrium. As a result of the tunneling, the <span class="hlt">core</span> of the initial string <span class="hlt">melts</span> while bubbles of true vacuum expand at the speed of light.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19910030600&hterms=earth+core&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dearth%2Bcore"><span id="translatedtitle">The nature of the earth's <span class="hlt">core</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jeanloz, Raymond</p> <p>1990-01-01</p> <p>The properties of the earth's <span class="hlt">core</span> are overviewed with emphasis on seismologically determined regions and pressures and seismologically measured density, elastic wave velocities, and gravitational acceleration. Attention is given to solid-state convection of the inner <span class="hlt">core</span>, and it is noted that though seismological results do not conclusively prove that the inner <span class="hlt">core</span> is convective, the occurrence and magnitude of seismic anisotropy are explained by the effects of solid-state convection. Igneous petrology and geochemistry of the inner <span class="hlt">core</span>, a layer at the base of the mantle and contact metasomatism at the <span class="hlt">core</span>-mantle boundary, and evolution of the <span class="hlt">core</span>-mantle system are discussed. It is pointed out that high-pressure <span class="hlt">melting</span> experiments indicate that the temperature of the <span class="hlt">core</span> is ranging from 4500 to 6500 K, and a major implication of such high temperature is that the tectonics and convection of the mantle, as well as the resulting geological processes observed at the surface, are powered by heat from the <span class="hlt">core</span>. As a result of the high temperatures, along with the compositional contrast between silicates and iron alloy, the <span class="hlt">core</span>-mantle boundary is considered to be most chemically active region of the earth.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/501519"><span id="translatedtitle">Late-phase <span class="hlt">melt</span> progression experiment: MP-2. Results and analysis</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gasser, R.D.; Gauntt, R.O.; Bourcier, S.C. [and others</p> <p>1997-05-01</p> <p>In-pile experiments addressing late-phase processes in Light Water Reactors (LWRs) were performed in the Annular <span class="hlt">Core</span> Research Reactor (ACRR) at Sandia National Laboratories. <span class="hlt">Melt</span> Progression (MP) experiments were designed to provide information to develop and verify computer models for analysis of LWR <span class="hlt">core</span> damage in severe accidents. Experiments examine the formation and motion of ceramic molten pools in disrupted reactor <span class="hlt">core</span> regions. The MP-2 experiment assembly consisted of: (1) a rubble bed of enriched UO{sub 2} and ZrO{sub 2} simulating severely disrupted reactor <span class="hlt">core</span> regions, (2) a ceramic/metallic crust representing blockage formed by early phase <span class="hlt">melting</span>, relocation, and refreezing of <span class="hlt">core</span> components, and (3) an intact rod stub region that remained in place below the blockage region. The test assembly was fission heated in the central cavity of the ACRR at an average rate of about 0.2 KA, reaching a peak molten pool temperature around 3400 K. <span class="hlt">Melting</span> of the debris bed ceramic components was initiated near the center of the bed. The molten material relocated downward, refreezing to form a ceramic crust near the bottom of the rubble bed. As power levels were increased, the crust gradually remelted and reformed at progressively lower positions in the bed until late in the experiment when it penetrated into and attacked the ceramic/metallic blockage. The metallic components of the blockage region <span class="hlt">melted</span> and relocated to the bottom of the intact rod stub region before the ceramic <span class="hlt">melt</span> penetrated the blockage region from above. The ceramic pool penetrated halfway into the blockage region by the end of the experiment. Measurements of thermal response and material relocation are compared to the results of the computer simulations. Postexperiment examination of the assembly with the associated material interactions and metallurgy are also discussed in detail with the analyses and interpretation of results. 16 refs., 206 figs., 24 tabs.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1993LPI....24..725J"><span id="translatedtitle">A Monazite-bearing clast in Apollo 17 <span class="hlt">melt</span> breccia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jolliff, Bradley L.</p> <p>1993-03-01</p> <p>A phosphate-rich clast in a pigeonite-plagioclase mineral assemblage occurs in Apollo 17 impact-<span class="hlt">melt</span> breccia 76503,7025. The clast, measuring 0.9 x 0.4 mm in thin section, contains 3.3 percent (volume) apatite (Ca5P3O12(F,Cl)), 0.8 percent whitlockite (Ca16(Mg,Fe)2REE2P14O56), and trace monazite ((LREE)PO4). Major minerals include 26 percent pigeonite, En53-57FS34-35W08-13, and 69 percent plagioclase, An84-92Ab7-15Oro.6-1.1. Troilite, ilmenite, and other accessory minerals constitute less than 1 percent of the assemblage and Fe-metal occurs along fractures. Also present in the <span class="hlt">melt</span> breccia as a separate clast is a fragment of felsite. Based on the association of these clasts and their assemblages, a parent lithology of alkali-anorthositic monzogabbro is <span class="hlt">postulated</span>. Monazite occurs in the phosphate-bearing clast as two less than 10 micron grains intergrown with whitlockite. The concentration of combined REE oxides in monazite is 63.5 percent and the chondrite-normalized REE pattern is strongly enriched in LREE, similar to lunar monazite in 10047,68 and terrestrial monazite. Thorium concentration was not measured in monazite, but based on oxide analyses of approximately 100 percent (including interpolated values for REE not measured), substantial Th concentration is not indicated, similar to monazite in 10047,68. Measured monazite/whitlockite REE ratios are La: 11, Ce: 8, Sm: 3.6, Y: 0.9, and Yb: 0.5. Compositions of monazite and coexisting whitlockite and apatite are given.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/25702027"><span id="translatedtitle">Simulation studies on architecture dependence of unentangled polymer <span class="hlt">melts</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xu, Xiaolei; Chen, Jizhong; An, Lijia</p> <p>2015-02-21</p> <p>The dependences of the properties of linear, ring, star, and H-shaped polymer <span class="hlt">melts</span> on architecture are investigated by nonequilibrium molecular dynamics simulations. We find that zero-shear viscosities ?0 for various architectures follow a universal relation, ?0=C??Rg0 (2)?, where C? is a constant and ?Rg0 (2)? the equilibrium mean-square radius of gyration, in the unentangled regime. This law is also found valid for asymmetrical polymers but invalid for polymers with a hard <span class="hlt">core</span>, such as stars with many arms and short arm lengths. In the unentangled regime, from the point of view of polymer size, the relaxation times show weak dependences on architecture, but the architecture dependence of the diffusion coefficient is still apparent. Then, we examine unentangled <span class="hlt">melts</span> of various architectures having the same size over a wide range of shear rates covering linear and nonlinear viscoelastic regimes and find that the rheological quantities, namely, viscosity, first and second normal stress differences, are independent of architecture. In contrast, the polymer deformation shows an apparent dependence on architecture in the nonlinear regime. These findings shall shed significant light on the nature of rheological behaviors of unentangled <span class="hlt">melts</span>. PMID:25702027</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/41984917"><span id="translatedtitle">Numerical simulation of earth's <span class="hlt">core</span> formation</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Rie Honda; Hitoshi Mizutani; Tetsuo Yamamoto</p> <p>1993-01-01</p> <p>Formation process of earth's <span class="hlt">core</span> is studied by numerical simulations of flow field in a self-gravitating fluid sphere. The proto-earth was assumed to have gravitationally unstable three-layered structure initially, which consists of the uppermost silicate <span class="hlt">melt</span> layer, the middle iron layer, and the central undifferentiated silicate-rich protocore. This structure of the heavy iron layer overlying the light protocore leads to</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFMDI33B..09G"><span id="translatedtitle"><span class="hlt">Core</span> and early crust formation on Mars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Golabek, G. J.; Keller, T.; Gerya, T.; Tackley, P. J.; Connolly, J.; Zhu, G.</p> <p>2010-12-01</p> <p>One of the most striking surface features on Mars is the crustal dichotomy. It is the oldest geological feature on Mars and was formed more than 4.1 Ga ago by either exogenic or endogenic processes [1,2]. In order to find an internal origin of the crustal dichotomy, located within a maximum of 400 Ma of planetary differentiation, the thermal state of the planet resulting from <span class="hlt">core</span> formation needs to be considered. Additionally, it was suggested that a primordial crust with up to 45 km thickness can be formed already during the Martian <span class="hlt">core</span> formation [3]. We suggest that the sinking of iron diapirs delivered by predifferentiated impactors induced impact- and shear heating-related temperature anomalies in the mantle that fostered the formation of early Martian crust. Thus, the crustal thickness distribution would largely be a result of planetary <span class="hlt">core</span> formation, late impact history and the onset of mantle convection. To test this hypothesis we use numerical models to simulate the formation of the Martian iron <span class="hlt">core</span> and the resulting mantle convection pattern, while peridotite <span class="hlt">melting</span> is enabled to track <span class="hlt">melting</span> caused by shear and radioactive heating. We perform 2D simulations using the spherical-Cartesian code I2ELVIS for planetary accretion and the spherical code STAGYY for the consequent onset of mantle convection. We apply a temperature-, stress- and <span class="hlt">melt</span>-fraction dependent viscoplastic rheology. Radioactive and shear heating as well as consumption of latent heat by silicate <span class="hlt">melting</span> are taken into account. The depth of neutral buoyancy of silicate <span class="hlt">melt</span> with respect to solid silicates is determined by the difference in compressibility of the liquid and solid phase. To self-consistently simulate the silicate phase changes expected inside a Mars-sized body, we use the thermodynamical database Perple_X. As initial condition for <span class="hlt">core</span> formation, we apply randomly distributed iron diapirs with 75 km radius inside the planet, representing the <span class="hlt">cores</span> of stochastically distributed impactors. Additionally, we explore the effect of one giant impactor <span class="hlt">core</span> on the planetary evolution. Results indicate that the presence of a large impactor <span class="hlt">core</span> induces hemispherically asymmetrical <span class="hlt">core</span> formation. The amplitude of shear heating anomalies often exceeds the solidus of primitive mantle material and thus, the formation of a considerable amount of silicate <span class="hlt">melt</span> is observed. The resulting temperature field after <span class="hlt">core</span> formation is then read into the mantle convection code STAYY. The hemispherical magma ocean induced by one late giant impactor favours a dichotomous crust formation during and shortly after <span class="hlt">core</span> formation. Afterwards, the extraction of excess heat produced by the sinking of the giant impactor through the mantle leads to a localized region of massive magmatism, comparable to Tharsis, which is sustained during later evolution by a single plume forming beneath the province. The rest of the mantle is dominated by a sluggish convection pattern with limited crust formation that preserves the early formed dichotomous crustal structure until recent time. References [1] Nimmo, F. et al., Nature, 453, 1220-1223, 2008. [2] Keller, T. & Tackley, P.J., Icarus, 202, 429-443, 2009. [3] Norman, M.D., Meteorit. Planet. Sci., 34, 439-449, 1999.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013JMMM..347....1W"><span id="translatedtitle">Fe-based nanocrystalline powder <span class="hlt">cores</span> with ultra-low <span class="hlt">core</span> loss</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Xiangyue; Lu, Zhichao; Lu, Caowei; Li, Deren</p> <p>2013-12-01</p> <p><span class="hlt">Melt</span>-spun amorphous Fe73.5Cu1Nb3Si15.5B7 alloy strip was crushed to make flake-shaped fine powders. The passivated powders by phosphoric acid were mixed with organic and inorganic binder, followed by cold compaction to form toroid-shaped bonded powder-metallurgical magnets. The powder <span class="hlt">cores</span> were heat-treated to crystallize the amorphous structure and to control the nano-grain structure. Well-coated phosphate-oxide insulation layer on the powder surface decreased the the <span class="hlt">core</span> loss with the insulation of each powder. FeCuNbSiB nanocrystalline alloy powder <span class="hlt">core</span> prepared from the powder having phosphate-oxide layer exhibits a stable permeability up to high frequency range over 2 MHz. Especially, the <span class="hlt">core</span> loss could be reduced remarkably. At the other hand, the softened inorganic binder in the annealing process could effectively improve the intensity of powder <span class="hlt">cores</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/26034277"><span id="translatedtitle">Imaging transient <span class="hlt">melting</span> of a nanocrystal using an X-ray laser.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Clark, Jesse N; Beitra, Loren; Xiong, Gang; Fritz, David M; Lemke, Henrik T; Zhu, Diling; Chollet, Matthieu; Williams, Garth J; Messerschmidt, Marc M; Abbey, Brian; Harder, Ross J; Korsunsky, Alexander M; Wark, Justin S; Reis, David A; Robinson, Ian K</p> <p>2015-06-16</p> <p>There is a fundamental interest in studying photoinduced dynamics in nanoparticles and nanostructures as it provides insight into their mechanical and thermal properties out of equilibrium and during phase transitions. Nanoparticles can display significantly different properties from the bulk, which is due to the interplay between their size, morphology, crystallinity, defect concentration, and surface properties. Particularly interesting scenarios arise when nanoparticles undergo phase transitions, such as <span class="hlt">melting</span> induced by an optical laser. Current theoretical evidence suggests that nanoparticles can undergo reversible nonhomogenous <span class="hlt">melting</span> with the formation of a <span class="hlt">core</span>-shell structure consisting of a liquid outer layer. To date, studies from ensembles of nanoparticles have tentatively suggested that such mechanisms are present. Here we demonstrate imaging transient <span class="hlt">melting</span> and softening of the acoustic phonon modes of an individual gold nanocrystal, using an X-ray free electron laser. The results demonstrate that the transient <span class="hlt">melting</span> is reversible and nonhomogenous, consistent with a <span class="hlt">core</span>-shell model of <span class="hlt">melting</span>. The results have implications for understanding transient processes in nanoparticles and determining their elastic properties as they undergo phase transitions. PMID:26034277</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6234645"><span id="translatedtitle">Preliminary analysis of the <span class="hlt">postulated</span> changes needed to achieve rail cask handling capabilities at selected light water reactors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Konzek, G.J.</p> <p>1986-02-01</p> <p>Reactor-specific railroad and crane information for all LWRs in the US was extracted from current sources of information. Based on this information, reactors were separated into two basic groups consisting of reactors with existing, usable rail cask capabilities and those without these capabilities. The latter group is the main focus of this study. The group of reactors without present rail cask handling capabilities was further separated into two subgroups consisting of reactors considered essentially incapable of handling a large rail cask of about 100 tons and reactors where <span class="hlt">postulated</span> facility changes could result in rail cask handling capabilities. Based on a selected population of 127 reactors, the results of this assessment indicate that usable rail cask capabilities exist at 83 (65%) of the reactors. Twelve (27%) of the remaining 44 reactors are deemed incapable of handling a large rail cask without major changes, and 32 reactors are considered likely candidates for potentially achieving rail cask handling capabilities. In the latter group, facility changes were <span class="hlt">postulated</span> that would conceptually enable these reactors to handle large rail casks. The estimated cost per plant of required facility changes varied widely from a high of about $35 million to a low of <$0.3 million. Only 11 of the 32 plants would require crane upgrades. Spur track and right-of-way costs would apparently vary widely among sites. These results are based on preliminary analyses using available generic cost data. They represent lower bound values that are useful for developing an initial assessment of the viability of the <span class="hlt">postulated</span> changes on a system-wide basis, but are not intended to be absolute values for specific reactors or sites.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://www.apsnet.org/edcenter/K-12/TeachersGuide/BrownRot/Pages/default.aspx"><span id="translatedtitle">Who Done It? Or what's that brown fuzzy stuff on my plum?: Koch's <span class="hlt">Postulates</span> for Proof of Pathogenicity</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p></p> <p>2012-06-26</p> <p>In this lab, learners explore Koch's <span class="hlt">Postulates</span>, the critical step used to prove that a particular microbe is the cause of a specific disease in a host organism (plant or animal). This is accomplished by examining the brown fuzzy stuff (a fungal pathogen) growing on a plum and experimentally showing, step by step, whether or not it is the cause of the observed disease. This lesson guide includes background information, instructions for leading a simplified (less time intensive) demonstration of the Germ Theory, study questions and answers, suggestions for additional experiments, and supplemental information and references. Adult supervision recommended.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013AGUFM.V32D..05K"><span id="translatedtitle">Seismogenic frictional <span class="hlt">melting</span> in the magmatic column as the driving force of stick-slip motion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kendrick, J. E.; Lavallee, Y.; Hirose, T.; Di Toro, G.; Hornby, A.; De Angelis, S.; Henton De Angelis, S.; Ferk, A.; Hess, K.; Leonhardt, R.; Dingwell, D. B.</p> <p>2013-12-01</p> <p>Lava dome eruptions subjected to high extrusion rates commonly evolve from endogenous to exogenous growth and limits to their structural stability hold catastrophic potential as explosive eruption triggers. In the conduit strain localisation in magma, accompanied by seismogenic failure, marks the onset of brittle magma ascent dynamics. The rock record of exogenous dome structures preserves vestiges of cataclastic processes and of thermal anomalies, key to unravelling subsurface processes. A combined structural, thermal and magnetic investigation of shear bands from Mount St. Helens (MSH) and Soufrière Hills volcano (SHV) reveal evidence of faulting and frictional <span class="hlt">melting</span> within the magmatic column. High velocity rotary shear (HVR) experiments demonstrate the propensity for <span class="hlt">melting</span> of andesitic and dacitic material (from SHV and MSH respectively) at upper conduit stress conditions. Such <span class="hlt">melting</span> events may be linked to the step-wise extrusion of magma accompanied by repetitive long-period (LP) seismicity. Using a source duration calculated from the waveforms at seismic stations around SHV, and slip distance per drumbeat calculated from extrusion rate, frictional <span class="hlt">melting</span> of SHV andesite in a high velocity rotary shear apparatus can be achieved at small slip distances (<15cm) in 0.15 s from 800°C magma (at 10MPa). The shear resistance of the slip zone during the experiments is also monitored. Frictional <span class="hlt">melting</span> induces a higher resistance to sliding than rock on rock, and viscous processes control the slip zone properties. Variable-rate HVR experiments which mimic rapid velocity fluctuations in stick-slip behavior demonstrate velocity-weakening behavior of <span class="hlt">melt</span>, with a tendency for unstable slip. We <span class="hlt">postulate</span> that pseudotachylyte generation could be the underlying cause of stick-slip motion and associated seismic 'drumbeats', which are so commonly observed at dome-building volcanoes, allowing for a fixed spatial locus and the occurrence of 'families' of similar seismic events. We conclude that, given the ease with which <span class="hlt">melting</span> is achieved in volcanic rocks, and considering the high ambient temperatures in volcanic conduits, frictional <span class="hlt">melting</span> is a highly probable consequence of viscous magma ascent.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2008JPhCS.114a2031J"><span id="translatedtitle">450 kW plasma <span class="hlt">melting</span> system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jha, M. N.; Sahashrabuddhe, S. N.; Murthy, P. S. S.; Bapat, A. V.; Das, A. K.</p> <p>2008-05-01</p> <p>Plasma <span class="hlt">melting</span> technology can be used to meet the scrap recycle needs of reactive metals, superalloys and refractory materials such as titanium, zirconium and uranium alloys. Fabrication involving these reactive metals, share the common problem of generating a large amount of scrap where both low and high density inclusions become highly prevalent. Plasma <span class="hlt">melting</span> technology can be used for re-<span class="hlt">melting</span>, refining and production of premium grade metal ingot. 450kW multi-torch plasma <span class="hlt">melting</span> furnace is developed and commissioned by Laser & Plasma Technology Division for the re-<span class="hlt">melting</span> and refining of metals and scraps under controlled environment. This paper presents the vacuum system design for 450 kW plasma <span class="hlt">melting</span> furnace. The efficacy of vacuum system in cold condition is also tested and the results are included in the paper. The vacuum feed through design for the plasma torch handling mechanism is also discussed.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/16495996"><span id="translatedtitle">Aluminium control of argon solubility in silicate <span class="hlt">melts</span> under pressure.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bouhifd, M Ali; Jephcoat, Andrew P</p> <p>2006-02-23</p> <p>Understanding of the crystal chemistry of the Earth's deep mantle has evolved rapidly recently with the gradual acceptance of the importance of the effect of minor elements such as aluminium on the properties of major phases such as perovskite. In the early Earth, during its formation and segregation into rocky mantle and iron-rich <span class="hlt">core</span>, it is likely that silicate liquids played a large part in the transport of volatiles to or from the deep interior. The importance of aluminium on solubility mechanisms at high pressure has so far received little attention, even though aluminium has long been recognized as exerting strong control on liquid structures at ambient conditions. Here we present constraints on the solubility of argon in aluminosilicate <span class="hlt">melt</span> compositions up to 25 GPa and 3,000 K, using a laser-heated diamond-anvil cell. The argon contents reach a maximum that persists to pressures as high as 17 GPa (up to 500 km deep in an early magma ocean), well above that expected on the basis of Al-free <span class="hlt">melt</span> experiments. A distinct drop in argon solubility observed over a narrow pressure range correlates well with the expected void loss in the <span class="hlt">melt</span> structure predicted by recent molecular dynamics simulations. These results provide a process for noble gas sequestration in the mantle at various depths in a cooling magma ocean. The concept of shallow partial <span class="hlt">melting</span> as a unique process for extracting noble gases from the early Earth, thereby defining the initial atmospheric abundance, may therefore be oversimplified. PMID:16495996</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/51279278"><span id="translatedtitle">Rheology of <span class="hlt">Melt</span>-bearing Crustal Rocks</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>C. L. Rosenberg; S. Medvedev; M. R. Handy</p> <p>2006-01-01</p> <p>A review and reinterpretation of previous experimental data on the deformation of <span class="hlt">melt</span>-bearing crustal rocks (Rosenberg and Handy, 2005) revealed that the relationship of aggregate strength to <span class="hlt">melt</span> fraction is non-linear, even if plotted on a linear ordinate and abscissa. At <span class="hlt">melt</span> fractions, Phi 0.07, the dependence of aggregate strength on Phi is significantly greater than at Phi > 0.07.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.springerlink.com/index/hqeqjqfpv63q8ryu.pdf"><span id="translatedtitle">Aluminosilicate <span class="hlt">melts</span>: structure, composition and temperature</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Bjorn Mysen</p> <p>1997-01-01</p> <p>The anionic structure of aluminosilicate <span class="hlt">melts</span> of intermediate degree of polymerization (NBO\\/T = 0.5) and with along the composition join (LS4-LA4) has been examined in-situ to ˜1480?°C, and compared with recent data for <span class="hlt">melts</span> along the analog composition join\\u000a and with less polymerized <span class="hlt">melts</span> along the join and O_5. With , the anionic equilibrium, (1) , adequately describes the structure.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/10329719"><span id="translatedtitle">Crystal Growth from the <span class="hlt">Melt</span>: A Review</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>R. Jeuss Knrpnrnrcr</p> <p></p> <p>This paper reviews four aspects of crystal growth theory: the nature of the rate-controlling process, the mechanism controlling molecular attachment onto the growing crystal surface, the nature of the crystal-<span class="hlt">melt</span> interface, and the stability of planar interfaces relative to cellular interfaces. The rate-controlling process may be diffusion in the <span class="hlt">melt</span>, heat flow, or the reaction at the crystal-<span class="hlt">melt</span> interface. Diffusion</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/10136350"><span id="translatedtitle">Fragmentation and quench behavior of corium <span class="hlt">melt</span> streams in water</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Spencer, B.W.; Wang, K.; Blomquist, C.A.; McUmber, L.M. [Argonne National Lab., IL (United States); Schneider, J.P. [Illinois Univ., Urbana, IL (United States). Dept. of Nuclear Engineering</p> <p>1994-02-01</p> <p>The interaction of molten <span class="hlt">core</span> materials with water has been investigated for the pour stream mixing mode. This interaction plays a crucial role during the later stages of in-vessel <span class="hlt">core</span> <span class="hlt">melt</span> progression inside a light water reactor such as during the TMI-2 accident. The key issues which arise during the molten <span class="hlt">core</span> relocation include: (i) the thermal attack and possible damage to the RPV lower head from the impinging molten fuel stream and/or the debris bed, (ii) the molten fuel relocation pathways including the effects of redistribution due to <span class="hlt">core</span> support structure and the reactor lower internals, (iii) the quench rate of the molten fuel through the water in the lower plenum, (iv) the steam generation and hydrogen generation during the interaction, (v) the transient pressurization of the primary system, and (vi) the possibility of a steam explosion. In order to understand these issues, a series of six experiments (designated CCM-1 through {minus}6) was performed in which molten corium passed through a deep pool of water in a long, slender pour stream mode. Results discussed include the transient temperatures and pressures, the rate and magnitude of steam/hydrogen generation, and the posttest debris characteristics.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60823832"><span id="translatedtitle"><span class="hlt">CORE</span> LEVITATION IN THE EGCR IN CASE OF MAIN COOLANT PIPE FAILURE</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Fontana</p> <p>2010-01-01</p> <p>Results of an analysis to determine the extent of displacement of the ;\\u000a EGCR <span class="hlt">core</span> due to blowdown in case of several <span class="hlt">postulated</span> hot main gas coolant pipe ;\\u000a failures are summarized. Results show that the <span class="hlt">core</span> will be damaged for ary hot ;\\u000a pipe double-ended failure. Excepting the improbable case of no coolant flow ;\\u000a existing prior to the</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19910042876&hterms=unknown&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dunknown"><span id="translatedtitle">Thermocapillary flow and natural convection in a <span class="hlt">melt</span> column with an unknown <span class="hlt">melt</span>/solid interface</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lan, C. W.; Kou, Sindo</p> <p>1991-01-01</p> <p>A vertical <span class="hlt">melt</span> column set up between an upper heating rod and a lower sample rod, i.e., the so-called half-zone system, is a convenient experimental tool for studying convection in the <span class="hlt">melt</span> in floating-zone crystal growth. In order to help understand the convection observed in the <span class="hlt">melt</span> column, a computer model has been developed to describe steady state, axisymmetrical thermocapillary flow and natural convection in the <span class="hlt">melt</span>. The governing equations and boundary conditions are expressed in general non-orthogonal curvilinear coordinates in order to accurately treat the unknown <span class="hlt">melt</span>/solid interface as well as all other physical boundaries in the system. The effects of key dimensionless variables on the following items are discussed: (1) convection and temperature distribution in the <span class="hlt">melt</span>; (2) the shape of the <span class="hlt">melt</span>/solid interface; (3) the height of the <span class="hlt">melt</span> column. These dimensionless variables are the Grashof, Marangoni and Prandtl numbers.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/1008949"><span id="translatedtitle">Tomographic location of potential <span class="hlt">melt</span>-bearing phenocrysts in lunar glass spherules</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ebel, D.S.; Fogel, R.A.; Rivers, M.L. (AMNH); (UC)</p> <p>2005-02-04</p> <p>Apollo 17 orange glass spherules contain olivine phenocrysts with <span class="hlt">melt</span> inclusions from depth. Tomography (<2micron/pxl) of >200 spherules located 1 phenocryst. We will try to find <span class="hlt">melt</span> inclusions and obtain original magma volatiles and compositions. In 1971, Apollo 17 astronauts collected a 10 cm soil sample (74220) comprised almost entirely of orange glass spherules. Below this, a double drive-tube <span class="hlt">core</span> sampled a 68 cm thick horizon comprised of orange glass and black beads (crystallized equivalents of orange glass). Primitive lunar glass spherules (e.g.-A17 orange glasses) are thought to represent ejecta from lunar mare fire fountains. The fire-fountains were apparently driven by a combination of C-O gas exsolution from orange glass <span class="hlt">melt</span> and the oxidation of graphite. Upon eruption, magmas lost their volatiles (e.g., S, CO, CO{sub 2}) to space. Evidence for volatile escape remains as volatile-rich coatings on the exteriors of many spherules. Moreover, it showed that Type I and II Fe-Ni-rich metal particles found within orange glass olivine phenocrysts, or free-floating in the glass itself, are powerful evidence for the volatile driving force for lunar fire fountains. More direct evidence for the volatile mechanism has yet to be uncovered. Issues remaining include: the exact composition of magmatic volatiles; the hypothesized existence of graphite in the magma; the oxygen fugacity of the magma and of the lunar interior. In 1996 reported a single {approx}450 micron, equant olivine phenocryst, containing four glassy <span class="hlt">melt</span> inclusions (or inclusion <span class="hlt">cores</span>), the largest {approx}30micron in size, in a thin section of the 74001/2 drill <span class="hlt">core</span>. The <span class="hlt">melt</span> is assumed to sample the parent magma of the lunar basalts at depth, evidenced by the S content of the inclusion (600 ppm) which is 400 ppm greater than that of the orange glass host. Such <span class="hlt">melts</span> potentially contain a full complement of the volatile components of the parent magma, which can be analyzed by infrared spectroscopy. Although the A17 orange glass magma is thought to derive from {approx} 400 km depth, the calculations imply a 4 km depth of graphite oxidation (and <span class="hlt">melt</span> saturation in C-O volatiles) during ascent. We have imaged several hundred similar orange glass spherules, from sample 74220,764, using synchrotron x-ray computer-aided microtomography (XRCMT). Our goals: (1) locate similar phenocrysts containing <span class="hlt">melt</span> inclusions; (2) analyze phenocrysts to understand the evolution of the magma; (3) analyze <span class="hlt">melt</span> and fluid inclusions using EPMA and FTIR to obtain direct evidence of magmatic volatiles and pristine bulk compositions.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2010AGUFM.T23A2227L"><span id="translatedtitle">Systematics of <span class="hlt">melt</span> stagnation in peridotites from the Godzilla Megamullion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Loocke, M.; Snow, J. E.; Ohara, Y.</p> <p>2010-12-01</p> <p>The Godzilla Megamullion (GM) Massif is the largest known example of an Oceanic <span class="hlt">Core</span> Complex (OCC) or the exhumed footwall of a low angle-large offset oceanic detachment fault. It lies on the extinct Parece Vela Rift spreading center within the Parece Vela Back-arc Basin of the Philippine Sea. This has thus allowed for sampling of a young back-arc mantle section. Sampling of the massif has returned a dominantly ultramafic lithology, divided petrographically into depleted, fertile, and <span class="hlt">melt</span>-percolated groups (1). Petrographic analysis of the extant peridotite thin section collection found that 44% of all GM peridotites (71 out of 161) exhibit evidence of plagioclase impregnation compared to the worldwide abyssal peridotite average of ~20% (2). The mullion is divided up into three regions, the proximal region ( closest to termination of spreading), the medial region, and the distal region (furthest from the termination of spreading)(3).Observations by region provide that 53% ( 62 out of 116 samples) in the proximal region (15 dredges), 12% ( 2 out of 17 samples) in the medial mullion (3 dredges), and 25% (7 out of 28) in the distal mullion (5 dredges) show of evidence of plagioclase impregnation (4). Major element analyses of spinels were completed using the Cameca SX-50 Electron Microprobe facility at the University of Houston. The Cr# [100 x Cr/(Cr + Al)] ranges from 10 to 65 with TiO2 concentrations ranging from less than 0.01 up to 1.6 wt%. When the Cr#s of the samples are plotted along the massif, a pattern of <span class="hlt">melt</span> depletion exists that is consistent with the degree of plagioclase impregnation. In the distal region, Cr#s start at around an average of 35 and range up to 65 for <span class="hlt">melt</span> percolated samples. In the medial region, a drop off in Cr# of about 1 Cr# per kilometer is observed with the trend bottoming out at around a Cr# of 10. In the proximal region, Cr#s closer to the medial region are observed as having more fertile values of around 20 but are found amongst <span class="hlt">melt</span>-impregnated samples with values ranging up to 50. This range is seen as having increasing minimum and maximum values with distance away from the medial section until it reaches its peak at a base Cr# of 30 with a maximum of 65. From this trend, a general model for the secular evolution of the GM mantle section can be established (5). The ridge segment experienced normal mid-oceanic ridge growth with robust mantle <span class="hlt">melting</span> during the time period represented by the distal region. At the boundary to the medial region, a steep drop-off in <span class="hlt">melt</span> productivity was experienced, leading to minimal mantle <span class="hlt">melting</span> during the time period represented by the medial region. Soon thereafter, <span class="hlt">melting</span> began again, but was trapped in a thickened and cooling lithosphere, causing the <span class="hlt">melt</span> to pool and react with its host peridotite. (1) Ohara, et al., (2003) G3. 4 (7), 8611, 10.1029/2002GC000469. (2) Dick (1989) Geol Soc. Lond. Spec. Pub. 42:71-105. (3) Ohara, et al., (2009), Eos Trans. AGU, 90(52), Fall Meet. Suppl. Abst.Num. T33D-06 (4) Loocke, et al., (2009), Eos Trans. AGU, 90(52), Fall Meet. Suppl. Abst.Num. T21A-1776 (5) Snow, et al., (2009), Eos Trans. AGU, 90(52), Fall Meet. Suppl. Abst.Num. T33D-07</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015PEPI..243...22B"><span id="translatedtitle">The fluid dynamics of inner-<span class="hlt">core</span> growth</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buffett, Bruce; Matsui, Hiroaki</p> <p>2015-06-01</p> <p>Aspherical growth of the inner <span class="hlt">core</span> has been suggested as a mechanism to produce seismic anisotropy through alignment of crystal lattices. This mechanism is viable if the response to aspherical growth occurs by slow viscous deformation. The inner <span class="hlt">core</span> can also respond by <span class="hlt">melting</span> and solidification at the boundary if flow in the liquid <span class="hlt">core</span> can redistribute latent heat over the surface. We use a numerical geodynamo model to quantitatively assess the process of <span class="hlt">melting</span> and solidification, and find that the response to aspherical growth occurs primarily through phase transitions when the viscosity of the inner <span class="hlt">core</span> is 1021 Pa s or higher. A lower inner-<span class="hlt">core</span> viscosity favors viscous adjustment, but the associated stresses may be too low to produce substantial crystal alignment. Independent of the primary relaxation mechanism, we expect a persistent and large-scale flow of the liquid <span class="hlt">core</span> over the surface of the inner <span class="hlt">core</span>. The predicted flow should be large enough to affect the crystal orientation of hcp-iron alloys during solidification, yet the absence of detectable seismic anisotropy in the top 60-80 km is suggestive. Either the mechanism of flow-induced alignment does not apply in the <span class="hlt">core</span> or the intrinsic anisotropy of hcp iron at inner-<span class="hlt">core</span> conditions is weak. Future seismological modeling using the predicted distribution of lattice preferred orientation might establish whether this texture is detectable with current observations.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.springerlink.com/index/p1426126p2553kq5.pdf"><span id="translatedtitle">Anhydrous partial <span class="hlt">melting</span> of an iron-rich mantle II: primary <span class="hlt">melt</span> compositions at 15 kbar</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Constance M. Bertka; John R. Holloway</p> <p>1994-01-01</p> <p>Primary <span class="hlt">melt</span> and coexisting mineral compositions, at increasing degrees of partial <span class="hlt">melting</span> at 15 kbar, were determined for an iron-rich martian mantle composition, DW. The composition of primary <span class="hlt">melts</span> near the solidus was determined with basalt-peridotite sandwich experiments. In order to evaluate the approach of the liquids to equilibrium with a DW mantle assemblage, experiments were also performed to establish</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/49292411"><span id="translatedtitle">Manufacturing by combining Selective Laser <span class="hlt">Melting</span> and Selective Laser Erosion\\/laser re-<span class="hlt">melting</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>E. Yasa; J.-P. Kruth; J. Deckers</p> <p>2011-01-01</p> <p>This study presents an experimental investigation to improve Selective Laser <span class="hlt">Melting</span> (SLM) regarding aspects such as surface roughness, density, precision and micro machining capability by employing secondary processes such as Selective Laser Erosion (SLE) and laser re-<span class="hlt">melting</span>. SLM is a layered additive manufacturing technique for the direct fabrication of functional parts by fusing together metal powder particles. Laser re-<span class="hlt">melting</span>, applied</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53253931"><span id="translatedtitle">High velocity friction, <span class="hlt">melting</span> and weakening of silicatic rocks</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>S. B. Nielsen</p> <p>2008-01-01</p> <p>It is well-known that the large heat generated by fast sliding alters the frictional behavior of rocks. One well-documented example is that of <span class="hlt">melt</span> lubrication, both observed in laboratory experiments and attested on exhumed faults by the presence of solidified <span class="hlt">melt</span> (pseudotachylite). <span class="hlt">Melting</span> dynamics implies heat diffusion, <span class="hlt">melt</span> migration and inhomogeneous frictional shear inside a <span class="hlt">melt</span> layer of varying thickness:</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/48931910"><span id="translatedtitle"><span class="hlt">Melt</span> distribution in olivine rocks based on electrical conductivity measurements</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Saskia M. ten Grotenhuis; Martyn R. Drury; Chris J. Spiers; Colin J. Peach</p> <p>2005-01-01</p> <p>Properties of partially molten rocks depend strongly on the grain-scale <span class="hlt">melt</span> distribution. Experimental samples show a variety of microstructures, such as <span class="hlt">melt</span> lenses, layers, and multigrain <span class="hlt">melt</span> pools, which are not readily explained using the theory for <span class="hlt">melt</span> distribution based on isotropic interface energies. These microstructures affect the <span class="hlt">melt</span> distribution and the porosity-permeability relation. It is still unclear how the</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/40848179"><span id="translatedtitle"><span class="hlt">Melt</span> aggregation within the crust beneath the Mid-Atlantic Ridge: evidence from plagioclase and clinopyroxene major and trace element compositions</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Laurence A. Coogan; Pamela D. Kempton; Andrew D. Saunders; Michael J. Norry</p> <p>2000-01-01</p> <p>Ocean Drilling Program Hole 923A, located on the western flank of the Mid-Atlantic Ridge south of the Kane Fracture Zone, recovered primitive gabbros that have mineral trace element compositions inconsistent with growth from a single parental <span class="hlt">melt</span>. Plagioclase crystals commonly show embayed anorthitic <span class="hlt">cores</span> overgrown by more albitic rims. Ion probe analyses of plagioclase <span class="hlt">cores</span> and rims show consistent differences</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2012AGUFMDI12A..07M"><span id="translatedtitle">Translation and convection of Earth's inner <span class="hlt">core</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Monnereau, M.; Calvet, M.; Margerin, L.; Mizzon, H.; Souriau, A.</p> <p>2012-12-01</p> <p>The image of the inner <span class="hlt">core</span> growing slowly at the center of the Earth by gradual cooling and solidification of the surrounding liquid outer <span class="hlt">core</span> is being replaced by the more vigorous image of a ``deep foundry'', where <span class="hlt">melting</span> and crystallization rates exceed by many times the net growth rate. Recently, a particular mode of convection, called translation, has been put forward as an important mode of inner <span class="hlt">core</span> dynamics because this mechanism is able to explain the observed East-West asymmetry of P-wave velocity and attenuation (Monnereau et al. 2010). Translation is a pure solid displacement of the inner <span class="hlt">core</span> material (solid iron) within its envelop, implying crystallization of entering iron on one side of the inner <span class="hlt">core</span> and <span class="hlt">melting</span> on the opposite side. Translation is consistent with multiple scattering models of wave propagation. If they do not experience deformation, iron crystals grow as they transit from one hemisphere to the other. Larger crystals constituting a faster and more attenuating medium, a translation velocity of some cm/yr (about ten times the growth rate) is enough to account for the superficial asymmetry observed for P-wave velocity and attenuation, with grains of a few hundred meters on the crystallizing side (West) growing up to a few kilometers before <span class="hlt">melting</span> on the East side, and a drift direction located in the equatorial plane. Among all hypotheses that have been proposed to account for the seismic asymmetry, translation is the only one based on a demonstrated link between the seismic data and the proposed dynamics, notably through a model of seismic wave propagation. This mechanism was also proposed to be responsible for the formation of a dense layer at the bottom of the outer <span class="hlt">core</span>, since the high rate of <span class="hlt">melting</span> and crystallization would release a liquid depleted in light elements at the surface of the inner <span class="hlt">core</span> (Alboussiere et al 2010). This would explain the anomalously low gradient of P wave velocity in the lowermost 200 km of the outer <span class="hlt">core</span>. Translation is a particular solution of Navier-Stokes equation with permeable boundary conditions, but depending on the viscosity of the solid <span class="hlt">core</span>, modes with higher spherical harmonics degree can develop. At low viscosity, these modes can be dominant and dissipate the degree l=1 of thermal heterogeneities. Hence, a viscosity threshold may be expected below which translation cannot take place, thereby constraining the viscosity of iron at inner <span class="hlt">core</span> conditions. Using a hybrid finite-difference spherical harmonics Navier-Stokes solver, we investigate the interplay between translation and convection in a 3D spherical model with permeable boundary conditions. Our numerical simulations show the dominance of pure translation for viscosities of the inner <span class="hlt">core</span> higher than 5 x 1018 Pas. Translation is almost completely hampered by convective motions for viscosities lower than 1017 Pas and the phase change becomes an almost impermeable boundary. Between these values, a well developed circulation at the harmonic degree l=1 persists, but composed of localized cold downwellings, a passive upward flow taking place on the opposite side (the <span class="hlt">melting</span> side). Such a convective structure remains compatible with the seismic asymmetry. Alboussiere, T., Deguen, R., Melzani, M., 2010. Nature 466 (7307), 744-U9. Monnereau, M., Calvet, M., Margerin, L., Souriau, A., 2010. Science 328 (5981), 1014-1017.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PMC&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3415377"><span id="translatedtitle">Polymer Micelles with Crystalline <span class="hlt">Cores</span> for Thermally Triggered Release</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Glover, Amanda L.; Nikles, Sarah M.; Nikles, Jacqueline A.; Brazel, Christopher S.; Nikles, David E.</p> <p>2012-01-01</p> <p>Interest in the use of poly(ethylene glycol)-b-polycaprolactone diblock copolymers in a targeted, magnetically triggered drug delivery system has led to this study of the phase behavior of the polycaprolactone <span class="hlt">core</span>. Four different diblock copolymers were prepared by the ring opening polymerization of caprolactone from the alcohol terminus of poly(ethylene glycol) monomethylether, Mn ~ 2,000. The critical micelle concentration depended on the degree of polymerization for the polycaprolactone block and was in the range of 2.9 to 41 mg/L. Differential scanning calorimetry curves for polymer solutions with a concentration above the critical micelle concentration showed a <span class="hlt">melting</span> endotherm in the range of 40 to 45°C, indicating the polycaprolactone <span class="hlt">core</span> was semicrystalline. Pyrene was entrapped in the micelle <span class="hlt">core</span> without interfering with the ability of the polycaprolactone to crystallize. When the polymer solution was heated above the <span class="hlt">melting</span> point of the micelle <span class="hlt">core</span>, the pyrene was free to leave the <span class="hlt">core</span>. Temperature dependent measurements of the critical micelle concentration and temperature dependent dynamic light scattering showed the micelles remain intact at temperatures above the <span class="hlt">melting</span> point of the polycaprolactone <span class="hlt">core</span>. PMID:22726124</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19940011800&hterms=transition+metal+oxides&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dtransition%2Bmetal%2Boxides"><span id="translatedtitle">Transition metals in superheat <span class="hlt">melts</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jakes, Petr; Wolfbauer, Michael-Patrick</p> <p>1993-01-01</p> <p>A series of experiments with silicate <span class="hlt">melts</span> doped with transition element oxides was carried out at atmospheric pressures of inert gas at temperatures exceeding liquidus. As predicted from the shape of fO2 buffer curves in T-fO2 diagrams the reducing conditions for a particular oxide-metal pair can be achieved through the T increase if the released oxygen is continuously removed. Experimental studies suggest that transition metals such as Cr or V behave as siderophile elements at temperatures exceeding liquidus temperatures if the system is not buffered by the presence of other oxide of more siderophile element. For example the presence of FeO prevents the reduction of Cr2O3. The sequence of decreasing siderophility of transition elements at superheat conditions (Mo, Ni, Fe, Cr) matches the decreasing degree of depletion of siderophile elements in mantle rocks as compared to chondrites.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/1028606"><span id="translatedtitle">Surface <span class="hlt">melting</span> of electronic order.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wilkins, S. B.; Liu, X.; Wakabayashi, Y.; Kim, J.-W.; Ryan, P. J.; Mitchell, J. F.; Hill, J. P. (Materials Science Division); ( XSD); (BNL); (Osaka Univ.)</p> <p>2011-01-01</p> <p>We report temperature-dependent surface x-ray scattering studies of the orbital ordered surface in La{sub 0.5}Sr{sub 1.5}MnO{sub 4}. We find that as the bulk ordering temperature is approached from below the thickness of the interface between the electronically ordered and electronically disordered regions at the surface grows, though the bulk correlation length remains unchanged. Close to the transition, the surface is so rough that there is no well-defined electronic surface, despite the presence of bulk electronic order. That is, the electronic ordering at the surface has <span class="hlt">melted</span>. Above the bulk transition, long-range ordering in the bulk is destroyed but finite-sized isotropic fluctuations persist, with a correlation length roughly equal to that of the low-temperature in-plane surface correlation length.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1402.1118v1"><span id="translatedtitle">Universality of Block Copolymer <span class="hlt">Melts</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Jens Glaser; Pavani Medapuram; Thomas M. Beardsley; Mark W. Matsen; David C. Morse</p> <p>2014-02-05</p> <p>Simulations of five different coarse-grained models of symmetric diblock copolymer <span class="hlt">melts</span> are compared to demonstrate a universal (i.e., model-independent) dependence of the free energy on the invariant degree of polymerization $\\overline{N}$, and to study universal properties of the order-disorder transition (ODT). The ODT appears to exhibit two regimes: Systems of very long chains ($\\overline{N} \\gtrsim 10^{4}$) are well described by the Fredrickson-Helfand theory, which assumes weak segregation near the ODT. Systems of smaller but experimentally relevant values, $\\overline{N} \\lesssim 10^4$, undergo a transition between strongly segregated disordered and lamellar phases that, though universal, is not adequately described by any existing theory.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19770024270&hterms=heat+affected+zone&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3D%2522heat%2B%252B%2Baffected%2B%252B%2Bzone%2522"><span id="translatedtitle">M551 metals <span class="hlt">melting</span> experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Busch, G.</p> <p>1977-01-01</p> <p>Electron beam welding studies were conducted in the Skylab M551 metals <span class="hlt">melting</span> experiment, on three different materials; namely 2219-T87 aluminum alloy, 304L stainless steel, and commercially pure tantalum (0.5 wt % columbium). Welds were made in both one gravity and zero gravity (Skylab) environments. Segments from each of the welds were investigated by microhardness, optical microscopy, scanning microscopy, and electron probe techniques. In the 2219-T87 aluminum alloy samples, macroscopic banding and the presence of an eutectic phase in the grain boundaries of the heat affected zone were observed. The stainless steel samples exhibited a sharp weld interface and macroscopic bands. The primary microstructural features found in the tantalum were the presence of either columnar grains (ground base) or equiaxed grains (Skylab). The factors contributing to these effects are discussed and the role of reduced gravity in welding is considered.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19800046195&hterms=Hard+sphere+model&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3D%2522Hard%2Bsphere%2Bmodel%2522"><span id="translatedtitle">Applications of liquid state physics to the earth's <span class="hlt">core</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stevenson, D. J.</p> <p>1980-01-01</p> <p>New results derived for application to the earth's outer <span class="hlt">core</span> using the modern theory of liquids and the hard-sphere model of liquid structure are presented. An expression derived in terms of the incompressibility and pressure is valid for a high-pressure liquid near its <span class="hlt">melting</span> point, provided that the pressure is derived from a strongly repulsive pair potential; a relation derived between the <span class="hlt">melting</span> point and density leads to a <span class="hlt">melting</span> curve law of essentially the same form as Lindemann's law. Finally, it is shown that the '<span class="hlt">core</span> paradox' of Higgins and Kennedy (1971) can occur only if the Gruneisen parameter is smaller than 2/3, and this constant is larger than this value in any liquid for which the pair potential is strongly repulsive.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/59160805"><span id="translatedtitle">SCALE MODELING OF ALUMINUM <span class="hlt">MELTING</span> FURNACE</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Sita rama raju S Penmetsa</p> <p>2004-01-01</p> <p>Secondary (recycled) aluminum constitutes around 48% of the total aluminum used in the United States. Secondary aluminum <span class="hlt">melting</span> is accomplished in large reverberatory furnaces, and improving its energy efficiency has been one of the major interests to aluminum industries. To assist the industries in improving energy efficiency in aluminum <span class="hlt">melting</span>, an experimental research furnace (ERF), with 907 kg (2000 lbs)</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19800039547&hterms=History+relations&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DHistory%2Brelations"><span id="translatedtitle">Impact <span class="hlt">melting</span> early in lunar history</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lange, M. A.; Ahrens, T. J.</p> <p>1979-01-01</p> <p>The total amount of impact <span class="hlt">melt</span> produced during early lunar history is examined in light of theoretically and experimentally determined relations between crater diameter (D) and impact <span class="hlt">melt</span> volume. The time dependence of the <span class="hlt">melt</span> production is given by the time dependent impact rate as derived from cratering statistics for two different crater-size classes. Results show that small scale cratering (D less than or equal to 30 km) leads to <span class="hlt">melt</span> volumes which fit selected observations specifying the amount of impact <span class="hlt">melt</span> contained in the lunar regolith and in craters with diameters less than 10 km. Larger craters (D greater than 30 km) are capable of forming the abundant impact <span class="hlt">melt</span> breccias found on the lunar surface. The group of large craters (D greater than 30 km) produces nearly 10 times as much impact <span class="hlt">melt</span> as all the smaller craters, and thus, the large impacts dominate the modification of the lunar surface. A contradiction between the distribution of radiometric rock ages and a model of exponentially decreasing cratering rate going back to 4.5 b.y. is reflected in uncertainty in the distribution of impact <span class="hlt">melt</span> as a function of time on the moon.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=DOE-PATENT-XML&redirectUrl=http://www.osti.gov/doepatents/biblio/872603"><span id="translatedtitle">Purification of tantalum by plasma arc <span class="hlt">melting</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Dunn, Paul S. (Santa Fe, NM); Korzekwa, Deniece R. (Los Alamos, NM)</p> <p>1999-01-01</p> <p>Purification of tantalum by plasma arc <span class="hlt">melting</span>. The level of oxygen and carbon impurities in tantalum was reduced by plasma arc <span class="hlt">melting</span> the tantalum using a flowing plasma gas generated from a gas mixture of helium and hydrogen. The flowing plasma gases of the present invention were found to be superior to other known flowing plasma gases used for this purpose.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19900016958&hterms=natural+convection+spherical&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dnatural%2Bconvection%2Bspherical"><span id="translatedtitle">Natural <span class="hlt">melting</span> within a spherical shell</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bahrami, Parviz A.</p> <p>1990-01-01</p> <p>Fundamental heat transfer experiments were performed on the <span class="hlt">melting</span> of a phase change medium in a spherical shell. Free expansion of the medium into a void space within the sphere was permitted. A step function temperature jump on the outer shell wall was imposed and the timewise evolution of the <span class="hlt">melting</span> process and the position of the solid-liquid interface was photographically recorded. Numerical integration of the interface position data yielded information about the <span class="hlt">melted</span> mass and the energy of <span class="hlt">melting</span>. It was found that the rate of <span class="hlt">melting</span> and the heat transfer were significantly affected by the movement of the solid medium to the base of the sphere due to gravity. The energy transfer associated with <span class="hlt">melting</span> was substantially higher than that predicted by the conduction model. Furthermore, the radio of the measured values of sensible energy in the liquid <span class="hlt">melt</span> to the energy of <span class="hlt">melting</span> were nearly proportional to the Stefan number. The experimental results are in agreement with a theory set forth in an earlier paper.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20070034157&hterms=Seasons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DSeasons"><span id="translatedtitle">Recent Changes in the Arctic <span class="hlt">Melt</span> Season</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stroeve, Julienne; Markus, Thorsten; Meier, Walter N.; Miller, Jeff</p> <p>2007-01-01</p> <p><span class="hlt">Melt</span>-season duration, <span class="hlt">melt</span>-onset and freeze-up dates are derived from satellite passive microwave data and analyzed from 1979 to 2005 over Arctic sea ice. Results indicate a shift towards a longer <span class="hlt">melt</span> season, particularly north of Alaska and Siberia, corresponding to large retreats of sea ice observed in these regions. Although there is large interannual and regional variability in the length of the <span class="hlt">melt</span> season, the Arctic is experiencing an overall lengthening of the <span class="hlt">melt</span> season at a rate of about 2 weeks decade(sup -1). In fact, all regions in the Arctic (except for the central Arctic) have statistically significant (at the 99% level or higher) longer <span class="hlt">melt</span> seasons by greater than 1 week decade(sup -1). The central Arctic shows a statistically significant trend (at the 98% level) of 5.4 days decade(sup -1). In 2005 the Arctic experienced its longest <span class="hlt">melt</span> season, corresponding with the least amount of sea ice since 1979 and the warmest temperatures since the 1880s. Overall, the length of the <span class="hlt">melt</span> season is inversely correlated with the lack of sea ice seen in September north of Alaska and Siberia, with a mean correlation of -0.8.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/51439676"><span id="translatedtitle">Electrohydrodynamic quenching in polymer <span class="hlt">melt</span> electrospinning</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Eduard Zhmayev; Daehwan Cho; Yong Lak Joo</p> <p>2011-01-01</p> <p>Infrared thermal measurements on polymer <span class="hlt">melt</span> jets in electrospinning have revealed rapid quenching by ambient air, an order of magnitude faster than predicted by the classical Kase and Matsuo correlation. This drastic heat transfer enhancement can be linked to electrohydrodynamic (EHD) effects. Analysis of EHD-driven air flow was performed and included into a comprehensive model for polymer <span class="hlt">melt</span> electrospinning. The</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/19219129"><span id="translatedtitle">Solid Clusters above the Bulk <span class="hlt">Melting</span> Point</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Alexandre A. Shvartsburg; Martin F. Jarrold</p> <p>2000-01-01</p> <p>The fact that the <span class="hlt">melting</span> points of nanoparticles are always lower than those of the corresponding bulk material is a paradigm supported by extensive experimental data for a large number of systems and by numerous calculations. Here we demonstrate that tin cluster ions with 10-30 atoms remain solid at ~50 K above the <span class="hlt">melting</span> point of bulk tin. This behavior</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://hal.archives-ouvertes.fr/docs/00/00/10/59/PS/paper.ps"><span id="translatedtitle">ccsd00001059 Continuous <span class="hlt">melting</span> of compact polymers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>ccsd­00001059 (version 1) : 26 Jan 2004 Continuous <span class="hlt">melting</span> of compact polymers Jesper Lykke relevant for polymers on surfaces, such as DNA adsorbed on a lipid bilayer. We predict a continuous <span class="hlt">melting</span> transition, and compute exact values of critical exponents at the transition point. Condensed phases</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19830000257&hterms=Melting+point&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3D%2528Melting%2Bpoint%2529"><span id="translatedtitle">Stabilizing Crystal Oscillators With <span class="hlt">Melting</span> Metals</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stephens, J. B.; Miller, C. G.</p> <p>1984-01-01</p> <p>Heat of fusion provides extended period of constant temperature and frequency. Crystal surrounded by metal in spherical container. As outside temperature rises to <span class="hlt">melting</span> point of metal, metal starts to liquefy; but temperature stays at <span class="hlt">melting</span> point until no solid metal remains. Potential terrestrial applications include low-power environmental telemetering transmitters and instrumentation transmitters for industrial processes.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/40921679"><span id="translatedtitle">The speciation of water in silicate <span class="hlt">melts</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Edward Stolper</p> <p>1982-01-01</p> <p>Previous models of water solubility in silicate <span class="hlt">melts</span> generally assume essentially complete reaction of water molecules to hydroxyl groups. In this paper a new model is proposed that is based on the hypothesis that the observed concentrations of molecular water and hydroxyl groups in hydrous silicate glasses reflect those of the <span class="hlt">melts</span> from which they were quenched. The new model</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=DOE-PATENT-XML&redirectUrl=http://www.osti.gov/doepatents/biblio/866076"><span id="translatedtitle"><span class="hlt">Melt</span> dumping in string stabilized ribbon growth</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Sachs, Emanuel M. (42 Old Middlesex Rd., Belmont, MA 02178)</p> <p>1986-12-09</p> <p>A method and apparatus for stabilizing the edge positions of a ribbon drawn from a <span class="hlt">melt</span> includes the use of wettable strings drawn in parallel up through the <span class="hlt">melt</span> surface, the ribbon being grown between the strings. A furnace and various features of the crucible used therein permit continuous automatic growth of flat ribbons without close temperature control or the need for visual inspection.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2011AGUFMMR31A2204T"><span id="translatedtitle">Possible Role of Hydrogen in the Earth <span class="hlt">Core</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takahashi, E.; Imai, T.</p> <p>2011-12-01</p> <p>Possible role of hydrogen in the Earth <span class="hlt">core</span> has been discussed by Stevenson (1977) and demonstrated experimentally by Fukai (1984), Okuchi (1997) and others. Planetary theory proposes a possibility of hydrogen incorporation in Earth's magma ocean from ambient solar nebula gas (Ikoma & Genda 2005, Genda & Ikoma 2008). More recently, migration of snow line during planet formation was examined (Min et al., 2010; Oka et al, 2011) and it was proposed that the Earth building material originally contained abundant water as ice and hydrous minerals. Therefore, it is very important to investigate the fate of water in the planet building process and clarify the role of hydrogen in the planetary <span class="hlt">core</span>. Using SPring-8 synchrotron (NaCl capsule, LiAlH4 as hydrogen source), we determined the <span class="hlt">melting</span> curve of FeH up to 20 GPa under hydrogen saturated conditions (Sakamaki, Takahashi et al, 2009). Observed <span class="hlt">melting</span> point is below 1300C and has a very small dT/dP slope. By extrapolating the <span class="hlt">melting</span> curve using Lindeman's law, we proposed that hydrogen could lower the <span class="hlt">melting</span> temperature of the Earth <span class="hlt">core</span> by more than 1500K than current estimate. Here we report our new experiments using SPring-8 synchrotron (single crystal diamond capsule, water as hydrogen source). Hydrogen concentration and <span class="hlt">melting</span> temperature of FeHx that coexists with hydrous mantle minerals were determined at 15-20GPa and 1000-1600C. We show that 1) hydrogen concentration in FeHx at 1000C, coexisting with hydrous-B and ringwoodite is approximately X=0.6. 2) Upon heating, hydrous-B decomposes and hydrogen strongly partitions into FeHx (X=0.8~1.0) than ringwoodite. 3) FeHx that coexists with ringwoodite <span class="hlt">melts</span> between ~1300C (solidus) and ~1600C (liquidus). Combined our new experiments with those by Sakamaki et al (2009) and Shibazaki et al (2009), partitioning of hydrogen between proto-<span class="hlt">core</span> and primitive mantle is discussed. We propose that >90% of water in the source material may have entered the Earth <span class="hlt">core</span>. Given large hydrogen concentration in the Earth <span class="hlt">core</span>, temperature of the outermost <span class="hlt">core</span> could be as low as that of lower mantle adiabat. Presence of the light element-rich layer at the top 300km layer of the outer <span class="hlt">core</span> (Helffrich & Kaneshima, 2010) may be easily understood if there is no temperature gap between the <span class="hlt">core</span> and the lower mantle.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/838870"><span id="translatedtitle">Metallic Recovery and Ferrous <span class="hlt">Melting</span> Processes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Luis Trueba</p> <p>2004-05-30</p> <p>The effects of <span class="hlt">melting</span> atmosphere and charge material type on the metallic and alloy recovery of ferrous charge materials were investigated in two sets of experiments (Tasks 1 and 2). In addition, thermodynamic studies were performed (Task 3) to determine the suitability of ladle treatment for the production of ductile iron using scrap charge materials high in manganese and sulfur. Task 1--In the first set of experiments, the charge materials investigated were thin steel scrap, thick steel scrap, cast iron scrap, and pig iron in the rusty and clean states. <span class="hlt">Melting</span> atmospheres in this set of experiments were varied by <span class="hlt">melting</span> with and without a furnace cover. In this study, it was found that neither covered <span class="hlt">melting</span> nor <span class="hlt">melting</span> clean (non-rusty) ferrous charge materials improved the metallic recovery over the recovery experienced with uncovered <span class="hlt">melting</span> or rusty charge materials. However, the silicon and manganese recoveries were greater with covered <span class="hlt">melting</span> and clean materials. Silicon and manganese in the molten iron react with oxygen dissolved in the iron from uncovered <span class="hlt">melting</span> and oxidized iron (surface rust). Silica and manganese silicates are formed which float to the slag decreasing recoveries of silicon and manganese. Cast iron and pig iron had higher metallic recoveries than steel scrap. Carbon recovery was affected by the carbon content of the charge materials, and not by the <span class="hlt">melting</span> conditions. Irons with higher silicon contents had higher silicon recovery than irons with lower silicon contents. Task 2--In the second set of experiments, briquetted turnings and borings were used to evaluate the effects of briquette cleanliness, carbon additions, and <span class="hlt">melting</span> atmosphere on metallic and alloy recovery. The <span class="hlt">melting</span> atmosphere in this set of experiments was varied by <span class="hlt">melting</span> in air and with an argon atmosphere using the SPAL process. In this set of experiments, carbon additions to the briquettes were found to have the greatest effect on metallic and alloy recovery. The use of an argon atmosphere was also found to increase recoveries, but to a lesser extent than with carbon additions to the briquettes. Task 3--Finally, thermodynamic studies were carried out to evaluate the potential for removing manganese and sulfur from iron <span class="hlt">melts</span> for the production of ferritic ductile iron. Thermodynamic calculations indicated that manganese and sulfur might be removed from iron <span class="hlt">melts</span> by careful control of the temperature and slag. In laboratory tests however, it was shown that the removal of sulfur was much less successful than that indicated by the thermodynamic analyses.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2001JChEd..78.1054L"><span id="translatedtitle"><span class="hlt">Melting</span> Point, Density, and Reactivity of Metals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Laing, Michael</p> <p>2001-08-01</p> <p>The density and <span class="hlt">melting</span> point of a metal, taken together, can give a useful qualitative guide to the chemical reactivity of the metal. A high density and high <span class="hlt">melting</span> point indicate a low reactivity; conversely, low density and low <span class="hlt">melting</span> point indicate high reactivity. The <span class="hlt">melting</span> point is allied to the heat of sublimation; the density gives a guide to the magnitude of the ionization energy. These two thermodynamic energy quantities are common to the Born-Haber cycles for the standard electrode potential, enthalpy of formation of the oxide, and reaction with water, which are commonly accepted thermodynamic measures of reactivity. Kinetic effects also play a role, not easy to quantify. A sharp discontinuity in the general trend of either <span class="hlt">melting</span> point or density in the middle of a long period points to anomalous or unusual chemical reactivity of the metal.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013Sci...341..266R"><span id="translatedtitle">Ice-Shelf <span class="hlt">Melting</span> Around Antarctica</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rignot, E.; Jacobs, S.; Mouginot, J.; Scheuchl, B.</p> <p>2013-07-01</p> <p>We compare the volume flux divergence of Antarctic ice shelves in 2007 and 2008 with 1979 to 2010 surface accumulation and 2003 to 2008 thinning to determine their rates of <span class="hlt">melting</span> and mass balance. Basal <span class="hlt">melt</span> of 1325 ± 235 gigatons per year (Gt/year) exceeds a calving flux of 1089 ± 139 Gt/year, making ice-shelf <span class="hlt">melting</span> the largest ablation process in Antarctica. The giant cold-cavity Ross, Filchner, and Ronne ice shelves covering two-thirds of the total ice-shelf area account for only 15% of net <span class="hlt">melting</span>. Half of the meltwater comes from 10 small, warm-cavity Southeast Pacific ice shelves occupying 8% of the area. A similar high <span class="hlt">melt</span>/area ratio is found for six East Antarctic ice shelves, implying undocumented strong ocean thermal forcing on their deep grounding lines.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2007RuMet2007..601L"><span id="translatedtitle">Determination of the <span class="hlt">melting</span> time of an Fe-Al ferroalloy in an iron-carbon <span class="hlt">melt</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lozovaya, E. Yu.; Zhuchkov, V. I.; Sheshukov, O. Yu.</p> <p>2007-12-01</p> <p>The <span class="hlt">melting</span> times of ferroaluminum alloys of various compositions have been calculated. A model for the <span class="hlt">melting</span> of these ferroalloys in an iron-carbon <span class="hlt">melt</span> is presented. The <span class="hlt">melting</span> time is found to depend on the aluminum content in the alloy, the ferroaluminum lump size, and the iron-carbon <span class="hlt">melt</span> temperature.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014APS..DPPTO5014R"><span id="translatedtitle">Investigation of the <span class="hlt">melting</span> of shock compressed Iron with XANES technique at LCLS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ravasio, A.; Harmand, M.; Denoeud, A.; Benuzzi-Mounaix, A.; Koenig, M.; Vinci, T.; Mazevet, S.; Musella, R.; Guyot, F.; Morard, G.; Dorchies, F.; Fourment, C.; Gaudin, J.; Feng, Y.; Zhu, D.; Lee, H. J.; Nagler, B.; Galtier, E. C.; Ozaki, N.; Miyanishi, K.; Toleikis, S.; Bouchet, J.; Recoules, V.; Nakatsutsumi, M.; Zastrau, U.</p> <p>2014-10-01</p> <p>X-ray Absorption Near Edge Spectroscopy is a powerful technique of both the electronic structure and the atomic short-range order in various media, from molecules to condensed matter. In a recent experiment performed at LCLS-MEC, we have applied this technique to study the <span class="hlt">melting</span> of Iron under shock compression. An accurate knowledge of its properties at high pressures and temperatures is indeed crucial for geophysics and planetary science. In particular, detailed information on <span class="hlt">melting</span> curves and solid phases are required to anchor the Earth's thermal profile and assess the solid or liquid nature of exoplanets' <span class="hlt">cores</span>. Here we will present the obtained results and discuss how XANES data unambiguously evidenced the <span class="hlt">melting</span> of iron on the high pressure Hugoniot.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20030064115&hterms=melt+deposition&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dmelt%2Bdeposition"><span id="translatedtitle">Composition of Impact <span class="hlt">Melt</span> Debris from the Eltanin Impact Strewn Field, Bellingshausen Sea</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kyte, Frank T.</p> <p>2002-01-01</p> <p>The impact of the km-sized Eltanin asteroid into the Bellingshausen Sea produced mm- to cm-sized vesicular impact <span class="hlt">melt</span>-rock particles found in sediment <span class="hlt">cores</span> across a large area of the ocean floor. These particles are composed mainly of olivine and glass with minor chromite and traces of NiFe-sulfides. Some particles have inclusions of unmelted mineral and rock fragments from the precursor asteroid. Although all samples of <span class="hlt">melt</span> rock examined have experienced significant alteration since their deposition in the late Pliocene, a significant portion of these particles have interiors that remain pristine and can be used to estimate the bulk composition of the impact <span class="hlt">melt</span>. The bulk composition of the <span class="hlt">melt</span>-rock particles is similar to the composition of basaltic meteorites such as howardites or mesosiderite silicates, with a contribution from seawater salts and a siderophile-rich component. There is no evidence that the Eltanin impact <span class="hlt">melt</span> contains a significant terrestrial silicate component that might have been incorporated by mixing of the projectile with oceanic crust. If terrestrial silicates were incorporated into the <span class="hlt">melt</span>, then their contribution must be much less than 10 wt%. Since excess K, Na, and CI are not present in seawater proportions, uptake of these elements into the <span class="hlt">melt</span> must have been greatest for K and least for CI, producing a K/CI ratio about 4 times that in seawater. After correcting for the seawater component, the bulk composition of the Eltanin impact <span class="hlt">melt</span> provides the best estimate of the bulk composition of the Eltanin asteroid. Excess Fe in the impact <span class="hlt">melt</span>, relative to that in howardites, must be from a significant metal phase in the parent asteroid. Although the estimated Fe:Ni:Ir ratios (8:1:4 x 10(exp -5)) are similar to those in mesosiderite metal nodules (10:1:6 x 10(exp -5), excess Co and Au by factors of about 2 and 10 times, respectively, imply a metal component distinct from that in typical mesosiderites. An alternative interpretation, that siderophiles have been highly fractionated from a mesosiderite source, would require loss of about 90% of the original metal from the impact <span class="hlt">melt</span> and the sediments, and is unsupported by any observational data. More likely, the excess Fe in the <span class="hlt">melt</span> rocks is 'representative of the amount of metal in the impacting asteroid, which is estimated to be 4+/- 1 wt%.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6251642"><span id="translatedtitle">Potential health risks from <span class="hlt">postulated</span> accidents involving the Pu-238 RTG (radioisotope thermoelectric generator) on the Ulysses solar exploration mission</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Goldman, M. (California Univ., Davis, CA (USA)); Nelson, R.C. (EG and G Idaho, Inc., Idaho Falls, ID (USA)); Bollinger, L. (Air Force Inspection and Safety Center, Kirtland AFB, NM (USA)); Hoover, M.D. (Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (USA). Inhalation Toxicology Research Inst.); Templeton, W. (Pacific Northwest Lab., Richland, WA (USA)); Anspaugh, L. (Lawren</p> <p>1990-11-02</p> <p>Potential radiation impacts from launch of the Ulysses solar exploration experiment were evaluated using eight <span class="hlt">postulated</span> accident scenarios. Lifetime individual dose estimates rarely exceeded 1 mrem. Most of the potential health effects would come from inhalation exposures immediately after an accident, rather than from ingestion of contaminated food or water, or from inhalation of resuspended plutonium from contaminated ground. For local Florida accidents (that is, during the first minute after launch), an average source term accident was estimated to cause a total added cancer risk of up to 0.2 deaths. For accidents at later times after launch, a worldwide cancer risk of up to three cases was calculated (with a four in a million probability). Upper bound estimates were calculated to be about 10 times higher. 83 refs.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2006AGUFM.V11F..06R"><span id="translatedtitle">Rheology of <span class="hlt">Melt</span>-bearing Crustal Rocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rosenberg, C. L.; Medvedev, S.; Handy, M. R.</p> <p>2006-12-01</p> <p>A review and reinterpretation of previous experimental data on the deformation of <span class="hlt">melt</span>-bearing crustal rocks (Rosenberg and Handy, 2005) revealed that the relationship of aggregate strength to <span class="hlt">melt</span> fraction is non-linear, even if plotted on a linear ordinate and abscissa. At <span class="hlt">melt</span> fractions, ? 0.07, the dependence of aggregate strength on ? is significantly greater than at ? > 0.07. This <span class="hlt">melt</span> fraction (?= 0.07) marks the transition from a significant increase in the proportion of <span class="hlt">melt</span>-bearing grain boundaries up to this point to a minor increase thereafter. Therefore, we suggest that the increase of <span class="hlt">melt</span>-interconnectivity causes the dramatic strength drop between the solidus and a <span class="hlt">melt</span> fraction of 0.07. A second strength drop occurs at higher <span class="hlt">melt</span> fractions and corresponds to the breakdown of the solid (crystal) framework, corresponding to the well-known "rheologically critical <span class="hlt">melt</span> percentage" (RCMP; Arzi, 1978). Although the strength drop at the RCMP is about 4 orders of magnitude, the absolute value of this drop is small compared to the absolute strength of the unmelted aggregate, rendering the RCMP invisible in a linear aggregate strength vs. <span class="hlt">melt</span> fraction diagram. Predicting the rheological properties and thresholds of <span class="hlt">melt</span>-bearing crust on the basis of the results and interpretations above is very difficult, because the rheological data base was obtained from experiments performed at undrained conditions in the brittle field. These conditions are unlikely to represent the flow of partially <span class="hlt">melted</span> crust. The measured strength of most of the experimentally deformed, partially-<span class="hlt">melted</span> samples corresponds to their maximum differential stress, before the onset of brittle failure, not to their viscous strength during "ductile" (viscous) flow. To overcome these problems, we extrapolated a theoretically-derived flow law for partially <span class="hlt">melted</span> granite deforming by diffusion-accommodated grain-boundary sliding (Paterson, 2001) and an experimentally-derived flow law for quartz deforming in the dislocation creep regime in the presence of 1-2 % of <span class="hlt">melt</span> (Gleason and Tullis, 1995). In addition, we compared these data with deformation experiments on olivine plus basalt <span class="hlt">melt</span>, also conducted in the ductile (viscous) field (Hirth and Kohlstedt, 2003). All these data show a dramatic decrease in viscosity for <span class="hlt">melt</span> fractions < 0.06. Therefore, they are consistent with the aforementioned results of experimentally deformed granite in the brittle field. Extrapolation of these results to natural conditions suggests that localisation of deformation should effectively coincide with the onset of <span class="hlt">melting</span>, or with very small <span class="hlt">melt</span> fractions (0.06-0.07), which may not always be detected in the field. References: Arzi, A. 1978. Tectonophysics, 44: 173-184. Hirth, G. and D. Kohlstedt. 2003. Geophysical Monograph, 138: 83-105. Gleason, G.C. and Tullis, J., 1995. Tectonophysics, 247: 1-23. Paterson, M.S. 2001. Tectonophysics, 335: 51-61. Rosenberg, C.L., and M.R. Handy. 2005. Journal of Metamorphic Geology, 23:19-28.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60592534"><span id="translatedtitle">Thermal Design of an Ultrahigh Temperature Vapor <span class="hlt">Core</span> Reactor Combined Cycle Nuclear Power Plant</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Samuel E. Bays; Samim Anghaie; Blair Smith; Travis Knight</p> <p>2004-01-01</p> <p>Current work modeling high temperature compact heat exchangers may demonstrate the design feasibility of a Vapor <span class="hlt">Core</span> Reactor (VCR) driven combined cycle power plant. For solid nuclear fuel designs, the cycle efficiency is typically limited by a metallurgical temperature limit which is dictated by fuel and structural <span class="hlt">melting</span> points. In a vapor <span class="hlt">core</span>, the gas\\/vapor phase nuclear fuel is uniformly</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60685240"><span id="translatedtitle">OECD MCCI project long-term 2-D molten <span class="hlt">core</span> concrete interaction test design report, Rev. 0. September 30, 2002</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>M. T. Farmer; D. J. Kilsdonk; S. Lomperski; R. W. Aeschliman; S. Basu</p> <p>2011-01-01</p> <p>The <span class="hlt">Melt</span> Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten <span class="hlt">core</span>-concrete interaction when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the <span class="hlt">melt</span> to the overlying water pool,</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/1014857"><span id="translatedtitle">OECD MCCI project <span class="hlt">Melt</span> Eruption Test (MET) design report, Rev. 2. April 15, 2003.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Farmer, M. T.; Lomperski, S.; Kilsdonk, D. J.; Aeschlimann, R. W.; Basu, S. (Nuclear Engineering Division); (NRC)</p> <p>2011-05-23</p> <p>The <span class="hlt">Melt</span> Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten <span class="hlt">core</span>-concrete interaction when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the <span class="hlt">melt</span> to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to <span class="hlt">melt</span> quenching. The <span class="hlt">Melt</span> Coolability and Concrete Interaction (MCCI) program is pursuing separate effect tests to examine the viability of the <span class="hlt">melt</span> coolability mechanisms identified as part of the MACE program. These mechanisms include bulk cooling, water ingression, volcanic eruptions, and crust breach. At the second PRG meeting held at ANL on 22-23 October 2002, a preliminary design1 for a separate effects test to investigate the <span class="hlt">melt</span> eruption cooling mechanism was presented for PRG review. At this meeting, NUPEC made several recommendations on the experiment approach aimed at optimizing the chances of achieving a floating crust boundary condition in this test. The principal recommendation was to incorporate a mortar sidewall liner into the test design, since data from the COTELS experiment program indicates that corium does not form a strong mechanical bond with this material. Other recommendations included: (i) reduction of the electrode elevation to well below the <span class="hlt">melt</span> upper surface elevation (since the crust may bond to these solid surfaces), and (ii) favorably taper the mortar liner to facilitate crust detachment and relocation during the experiment. Finally, as a precursor to implementing these modifications, the PRG recommended the development of a design for a small-scale scoping test intended to verify the ability of the mortar liner to preclude formation of an anchored bridge crust under <span class="hlt">core</span>-concrete interaction conditions. This revised <span class="hlt">Melt</span> Eruption Test (MET) plan is intended to satisfy these PRG recommendations. Specifically, the revised plan focuses on providing data on the extent of crust growth and <span class="hlt">melt</span> eruptions as a function of gas sparging rate under well-controlled experiment conditions, including a floating crust boundary condition. The overall objective of MET is to determine to what extent <span class="hlt">core</span> debris is rendered coolable by eruptive-type processes that breach the crust that rests upon the <span class="hlt">melt</span>. The specific objectives of this test are as follows: (1) Evaluate the augmentation in surface heat flux during periods of <span class="hlt">melt</span> eruption; (2) Evaluate the <span class="hlt">melt</span> entrainment coefficient from the heat flux and gas flow rate data for input into models that calculate ex-vessel debris coolability; (3) Characterize the morphology and coolability of debris resulting from eruptive processes that transport <span class="hlt">melt</span> into overlying water; and (4) Discriminate between periods when eruptions take the form of particle ejections into overlying water, leading to a porous particle bed, and single-phase extrusions, which lead to volcano-type structures.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014EGUGA..16.8372R"><span id="translatedtitle">Water solubility in rhyolitic silicate <span class="hlt">melts</span> at atmospheric pressure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ryan, Amy; Russell, Kelly; Nichols, Alexander; Porritt, Lucy; Friedlander, Elizabeth</p> <p>2014-05-01</p> <p>High temperature (900-1100 °C) experiments have been conducted to measure the solubility of water in a rhyolitic <span class="hlt">melt</span> at atmospheric pressure (1 atm) and to quantify the magnitude of retrograde solubility at low pressure. Individual <span class="hlt">cores</span> (1 cm x 1 cm) of crystal- and bubble-free rhyolitic obsidian from Hrafntinnugryggur, Krafla (Iceland) were held in a furnace at 900-1100 °C for 0.25 to 20 hours. During this time, the uniform bubble-free <span class="hlt">cores</span> vesiculate to produce variably swollen bubble-rich run products. The volume change in each <span class="hlt">core</span> reflects the volume of bubbles produced in each experiment and depends on the experimental temperature and the time held at that temperature. The run product volumes for isothermal experiments (e.g., 950 °C) increase non-linearly with increasing time (e.g., 0.18 cm3 at 1.5 h, 0.96 cm3 at 12.5 h) until reaching a maximum value, after which the volume does not change appreciably. We take this plateau in the isothermal volume:time curve as coinciding with the 1 atm. solubility limit for the rhyolite at this temperature. With increasing temperature, the slope and final horizontal plateaus of the volume:time curves increase such that samples from the higher temperature suites vesiculate more, as well as more rapidly (e.g., 0.85 cm3 after 0.5 hours, 1.78 cm3 after 1 hour at 1100 °C). The variations in the maximum volume of bubbles produced for each temperature constrain the retrograde solubility of water in the <span class="hlt">melt</span> at 1 atm. Fourier transform infrared spectroscopy (FTIR) analyses of the residual water content of the glass in the starting material and in the most vesiculated sample from each temperature suite shows a decrease in the water content of the glass from an initial 0.114 wt% (? 0.013) to 0.098 wt% (? 0.010), 0.087 wt% (? 0.009), 0.093 wt% (? 0.008), 0.090 wt% (? 0.006) and 0.108 wt% (? 0.010) for 900 °C, 950 °C, 1000 °C, 1050 °C and 1100 °C respectively. This change in the solubility of water at different temperatures, though slight, produces a marked change in maximum run product porosity from 50 to 70% through the temperature series, illuminating the effect of retrograde solubility at conduit- and surface-relevant pressures. The readiness of a rhyolitic silicate <span class="hlt">melt</span> not only to produce more bubbles at higher temperatures, but also to resorb existing bubbles during cooling has important implications for magmatic fragmentation, flow of lava, and welding processes.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2012E%26PSL.345...38H"><span id="translatedtitle">Solubility of molecular hydrogen in silicate <span class="hlt">melts</span> and consequences for volatile evolution of terrestrial planets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hirschmann, M. M.; Withers, A. C.; Ardia, P.; Foley, N. T.</p> <p>2012-09-01</p> <p>We present experiments from 0.7 to 3 GPa that quantify solubility of H2 in silicate <span class="hlt">melts</span> under controlled hydrogen fugacities (fH2). Two experimental series, one on synthetic basalt+COH and other with a synthetic andesite+OH, were conducted using a double capsule technique to impose a range of fH2, on the samples. Quenched glasses were analyzed by FTIR and SIMS. Both series follow simple solubility laws in which molecular H2 concentrations are proportional to fH2 and with a partial molar volume of molecular H2 of 11 cm3/mole. Solubilities in andesitic <span class="hlt">melt</span> are systematically greater than in basaltic liquid in a relationship consistent with control by the ionic porosity (IP) of the <span class="hlt">melts</span>. Extrapolation based on IP allows estimation of the solubility of H2 in peridotitic <span class="hlt">melts</span> applicable to magma oceans. The H2/(H2+H2O) ratio in silicate <span class="hlt">melts</span> (where H2O includes molecular H2O and OH-) increases as conditions become more reduced, with increasing pressure, and with increasing total H. Under some conditions prevailing in the early Earth and terrestrial planets as well as in the deep Earth today, H2 can be a significant fraction of the dissolved H and at high pressure it may exceed “water” (H2O and OH-). Therefore, magmatic H2 may influence the initial distribution of volatiles and the redox evolution of terrestrial planets, as well as the ongoing formation and fate of hydrous <span class="hlt">melts</span> in the deep Earth today. Hydrous species in <span class="hlt">melts</span> in equilibrium with Fe-rich alloy at high pressure, for example during <span class="hlt">core</span> formation from a magma ocean, could be chiefly H2, rather than H2O. Hence, delivery of H2 to the <span class="hlt">core</span> by removal of Fe hydride need not be coupled to oxidation of the residual mantle. Although lunar basalts are much reduced, the fraction of H dissolved as molecular H2 is small owing to low total H concentrations. Extrapolation to conditions of potential hydrous partial <span class="hlt">melting</span> in the deep Earth suggests that the chief magmatic volatile may be H2 rather than H2O. The very small partial specific density of magmatic H2 (0.18 g/cm3 at low pressure) may provide significant positive buoyancy to deep partial <span class="hlt">melts</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19860049976&hterms=siderite+siderite&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsiderite%2Bsiderite"><span id="translatedtitle"><span class="hlt">Melt</span> segregation in plagioclase-poikilitic mesosiderites</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hewins, R. H.; Harriott, T. A.</p> <p>1986-01-01</p> <p>The Budalan and Mincy mesosiderites contain a poikilitic-plagioclase matrix with orthopyroxene chadacrysts and interstitial-subophitic inverted pigeonite. Orthopyroxene chadacrysts in both mesosiderites are uniformly more aluminous than orthopyroxene clasts, suggesting that they were not derived from clasts by metamorphism. Interstitial inverted pigeonite is more ferroan than adjacent orthopyroxene in the matrix, consistent with the crystallization of a <span class="hlt">melt</span> with the sequence orthopyroxene followed by pigeonite. The magnesium chadcrysts in Mincy could not have formed from a <span class="hlt">melt</span> in equilibrium with the clasts but could have crystallized from impact <span class="hlt">melt</span>. The most Mg chadacrysts are enclosed in large reversely zoned plagioclase crystals as a result of the undercooling in <span class="hlt">melt</span>-lacking plagioclase clasts and associated nuclei. Mincy contains both plagioclase-poor and plagioclase-rich regions, explained by a separation of silicate <span class="hlt">melt</span> into pools. Reckling Peak A80258, a plagioclase-poikilitic mesosiderite with a very high chadacryst/plagioclase ratio, resembles Mincy material from which <span class="hlt">melt</span> has been extracted. It is suggested that the origin of the plagioclase-poikilitic mesosiderites is impact <span class="hlt">melting</span> of a metal-silicate mixture.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015EGUGA..17.1044C"><span id="translatedtitle">Cu refertilization of abyssal harzburgites by <span class="hlt">melt</span> percolation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ciazela, Jakub; Dick, Henry; Koepke, Juergen; Botcharnikov, Roman; Muszynski, Andrzej; Kuhn, Thomas</p> <p>2015-04-01</p> <p>Primitive mantle is depleted in many elements by partial <span class="hlt">melting</span> processes, but it can be subsequently refertilized by impregnation with percolating <span class="hlt">melts</span>. It is known that Cu can be enriched in primitive <span class="hlt">melts</span>, depleting mantle residue, due to the former process (Patten et al. 2013). However, the behavior of Cu in the processes of mantle-<span class="hlt">melt</span> interaction is poorly understood. The only comprehensive study is based on compositions of orogenic peridotites, representing the subcontinental mantle (Lorand et al. 1993; 2013), where a moderate enrichment of the mantle in Cu (up to ~50 ppm) has been observed. Here, we present the first results obtained for a suite of rocks from an oceanic <span class="hlt">core</span> complex (OCC), the Kane Megamullion at 22°30'N at the Mid-Atlantic Ridge (Dick et al. 2008). OCC's provide large exposures of mantle and lower crustal rocks on the seafloor on detachment fault footwalls at slow and ultraslow spreading ridges. The mantle rocks are composed of spinel and plagioclase harzburgites. The spinel harzburgites represent depleted mantle, whereas the plagioclase harzburgites were formed by subsequent late-stage <span class="hlt">melt</span> impregnation in the depleted mantle (Dick et al. 2010). We have determined Cu concentrations in 22 residual spinel harzburgites and 4 plagioclase harzburgites using total digestion ICP-MS. The average Cu concentration in spinel harzburgites is 35±11 ppm Cu (2?). The average Cu concentration obtained for plagioclase harzburgites is 131±33 ppm Cu (2?). Additionally, we have analyzed one 1.5 cm thick contact zone between an oxide gabbro vein and residual peridotite. The contact zone, which has been heavily impregnated by the <span class="hlt">melt</span>, contains 284 ppm Cu. In contrast, the neighboring oxide gabbro vein and the hosting peridotite contain 147 and 68 ppm Cu, respectively. Furthermore, we have determined the concentration of Cu in a dunite (118 ppm), formed in a reaction between the mantle and <span class="hlt">melt</span> ascending through the lithosphere (Dick et al. 2010). Magmatic processes in the rocks coming from OCCs can be obscured by deformation and alteration. Plastically deformed rocks are common in the damaged zone related to the detachment fault. Metaperidotites from these zones, which show protomylonitic to ultramylonitic textures, are systematically depleted in Cu (15±5 ppm, 2?) in comparison to non-deformed spinel harzburgites. We have not included the values obtained from non-deformed harzburgites in the calculation of the averages presented above. Thus, the effect of deformation processes does not influence our results. The relatively narrow 0.95 confidence intervals of the means obtained for non-deformed spinel and plagioclase harzburgite species and a large difference between the two means indicate a relatively low influence of alteration. Therefore, we believe the significant enrichment in Cu exhibited by the refertilized mantle rocks is caused exclusively by mantle impregnation with late-stage <span class="hlt">melts</span>. Enhanced Cu concentrations indicate that the scale of this enrichment can be significantly underestimated in previous studies (Lorand et al. 2013). Dick, H.J.B., Tivey, M.A. & Tucholke, B.E., 2008. Plutonic foundation of a slow-spreading ridge segment: Oceanic <span class="hlt">core</span> complex at Kane Megamullion, 23°30'N, 45°20'W. Geochemistry, Geophysics, Geosystems 9, Q05014. Dick, H.J.B., Lissenberg, C.J., & Warren, J.M., 2010. Mantle <span class="hlt">melting</span>, <span class="hlt">melt</span> transport, and delivery beneath a slow-spreading ridge: The paleo-MAR from 23°15'N to 23°45'N. Journal of Petrology 51, 425-467. Lorand, J.P., Keays, R.R. & Bodinier, J.L., 1993. Copper and noble metal enrichments across the lithosphere-astenosphere boundary of mantle diapirs: evidence from the Lanzo Lherzolite Massif. Journal of Petrology 34, 1111-1140. Lorand, J.P., Luguet, A. & Alard, O., 2013. Platinum-group element systematics and petrogenetics processing of the upper mantle: A review. Lithos 164-167, 2-21. Patten, C., Barnes, S.-J., Mathez, E.A. & Jenner, F.E., 2013. Partition coefficients of chalcophile elements between sulfide and silicate <span class="hlt">melts</span> and the earl</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013AGUFM.P51C1751E"><span id="translatedtitle"><span class="hlt">Melt</span> migration through Io's convecting mantle</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Elder, C. M.; Showman, A. P.</p> <p>2013-12-01</p> <p>The extensive volcanism occurring on the surface of Io suggests that its interior must contain at least some partial <span class="hlt">melt</span>. Unlike Earth, Io cannot lose its internal heat through convection alone [1]. Instead, <span class="hlt">melt</span> moving through the solid mantle helps remove heat from Io's interior by carrying its latent heat towards the surface as it buoyantly ascends through the mantle. We investigate this process by considering <span class="hlt">melt</span> migration in a column of rock rising through the mantle between downwelling plumes. Convective scaling laws provide the upwelling velocity and the temperature of the rising mantle. Properties of <span class="hlt">melt</span> migration in this rising mantle are calculated using porous flow equations and an equation for the conservation of energy which includes latent heat consumption, heat advection and heat conduction [2]. This combination of convective scaling laws and porous flow laws allows us to self-consistently determine the radial <span class="hlt">melt</span> fraction profile in Io's interior, the average <span class="hlt">melt</span> fraction in Io's interior and the heat flux due to advection of <span class="hlt">melt</span>. The average <span class="hlt">melt</span> fraction can be compared to the <span class="hlt">melt</span> fraction constraints calculated by [3] from Galileo magnetometer measurements. The surface heat flux calculations can be compared to the value of Io's observed surface heat flux which ranges with observation from 1.5-4 W m-2 [4]. [1] Moore W. B. (2003) J. Geophys. Res., 108, E8, 15-1. [2] Hewitt I. J. and Fowler A. C. (2008) Proc. R. Soc. A., 464, 2467-2491. [3] Khurana K. K. et al. (2011) Science, 332, 1186-1189. [4] Moore, W. B. et al. (2007) In: Io After Galileo, Springer-Praxis, 89-108.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/912205"><span id="translatedtitle">Late-Phase <span class="hlt">Melt</span> Conditions Affecting the Potential for In-Vessel Retention in High Power Reactors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>D. L. Knudson; J. L. Rempe; K. G. Condie; K. Y. Suh; F. B.Cheung; S. B. Kim</p> <p>2004-05-01</p> <p>If cooling is inadequate during a reactor accident, a significant amount of <span class="hlt">core</span> material could become molten and relocate to the lower head of the reactor vessel, as happened in the Three Mile Island Unit 2 accident. In such a case, concerns about containment failure and associated risks can be eliminated if it is possible to ensure that the lower head remains intact so that relocated <span class="hlt">core</span> materials are retained within the vessel. Accordingly, in-vessel retention (IVR) of <span class="hlt">core</span> <span class="hlt">melt</span> as a key severe accident management strategy has been adopted by some operating nuclear power plants and planned for some advanced light water reactors. However, it is not clear that currently proposed external reactor vessel cooling (ERVC) without additional enhancements can provide sufficient heat removal to assure IVR for high power reactors (i.e., reactors with power levels up to 1500 MWe). Consequently, a joint United States/Korean International Nuclear Energy Research Initiative (I-NERI) has been launched to develop recommendations to improve the margin of success for in-vessel retention in high power reactors. This program is initially focussed on the Korean Advanced Power Reactor—1400 MWe (APR1400) design. However, recommendations will be developed that can be applied to a wide range of existing and advanced reactor designs. The recommendations will focus on modifications to enhance ERVC and modifications to enhance in-vessel debris coolability. In this paper, late-phase <span class="hlt">melt</span> conditions affecting the potential for IVR of <span class="hlt">core</span> <span class="hlt">melt</span> in the APR1400 were established as a basis for developing the I-NERI recommendations. The selection of ‘bounding’ reactor accidents, simulation of those accidents using the SCDAP/RELAP5-3D© code, and resulting late-phase <span class="hlt">melt</span> conditions are presented. Results from this effort indicate that bounding late-phase <span class="hlt">melt</span> conditions could include large <span class="hlt">melt</span> masses (>120,000 kg) relocating at high temperatures (3400 K). Estimated lower head heat fluxes associated with this <span class="hlt">melt</span> could exceed the maximum critical heat flux, indicating additional measures such as the use of a <span class="hlt">core</span> catcher and/or modifications to enhance external reactor vessel cooling may be necessary to ensure in-vessel retention of <span class="hlt">core</span> <span class="hlt">melt</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/20197897"><span id="translatedtitle">Characteristics of laser surface <span class="hlt">melted</span> aluminum alloys.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Weinman, L S; Kim, C; Tucker, T R; Metzbower, E A</p> <p>1978-03-15</p> <p>Specimens of Al-Fe 1-4 w/o, 2024 and 6061 Al have been surface <span class="hlt">melted</span> with a pulsed Nd-glass laser. A TEM and SEM study showed that the dendrite spacings were from 2500 A to 4000 A which corresponds to a cooling rate of over 10(6) degrees C/sec. <span class="hlt">Melt</span> depths obtained were in the range of 30-100 microm. No significant surface vaporization was observed at energy densities up to 440 J/cm(2). Fracture surfaces of the commerical alloys demonstrated elongated porosity in the <span class="hlt">melt</span> areas, probably due to internal hydrogen. PMID:20197897</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2011PhFl...23g3102Z"><span id="translatedtitle">Electrohydrodynamic quenching in polymer <span class="hlt">melt</span> electrospinning</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhmayev, Eduard; Cho, Daehwan; Lak Joo, Yong</p> <p>2011-07-01</p> <p>Infrared thermal measurements on polymer <span class="hlt">melt</span> jets in electrospinning have revealed rapid quenching by ambient air, an order of magnitude faster than predicted by the classical Kase and Matsuo correlation. This drastic heat transfer enhancement can be linked to electrohydrodynamic (EHD) effects. Analysis of EHD-driven air flow was performed and included into a comprehensive model for polymer <span class="hlt">melt</span> electrospinning. The analysis was validated by excellent agreement of both predicted jet radius and temperature profiles with experimental results for electrospinning of Nylon-6 (N6), polypropylene (PP), and polylactic acid (PLA) <span class="hlt">melts</span>. Based on this analysis, several methods that can be used to inhibit or enhance the quenching are described.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/960510"><span id="translatedtitle">Physics of the Lindemann <span class="hlt">melting</span> rule</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lawson, Andrew C [Los Alamos National Laboratory</p> <p>2008-01-01</p> <p>We investigate the thermodynamics of <span class="hlt">melting</span> for 74 distinct chemical elements including several actinides and rare earths. We find that the observed <span class="hlt">melting</span> points are consistent with a linear relationship between the correlation entropy of the liquid and the Grueneisen constant of the solid, and that the Lindemann rule is well obeyed for the elements with simple structures and less well obeyed for the less symmetric more open structures. No special assumptions are required to explain the <span class="hlt">melting</span> points of the rare earths or light actinides.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19890018447&hterms=skull&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dskull"><span id="translatedtitle">Rapidly solidified titanium alloys by <span class="hlt">melt</span> overflow</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gaspar, Thomas A.; Bruce, Thomas J., Jr.; Hackman, Lloyd E.; Brasmer, Susan E.; Dantzig, Jonathan A.; Baeslack, William A., III</p> <p>1989-01-01</p> <p>A pilot plant scale furnace was designed and constructed for casting titanium alloy strips. The furnace combines plasma arc skull <span class="hlt">melting</span> techniques with <span class="hlt">melt</span> overflow rapid solidification technology. A mathematical model of the <span class="hlt">melting</span> and casting process was developed. The furnace cast strip of a suitable length and width for use with honeycomb structures. Titanium alloys Ti-6Al-4V and Ti-14Al-21 Nb were successfully cast into strips. The strips were evaluated by optical metallography, microhardness measurements, chemical analysis, and cold rolling.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60541193"><span id="translatedtitle">Assessment of the potential for high-pressure <span class="hlt">melt</span> ejection resulting from a Surry station blackout transient</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>D. L. Knudson; C. A. Dobbe</p> <p>1993-01-01</p> <p>Containment integrity could be challenged by direct heating associated with a high pressure <span class="hlt">melt</span> ejection (HPME) of <span class="hlt">core</span> materials following reactor vessel breach during certain severe accidents. Intentional reactor coolant system (RCS) depressurization, where operators latch pressurizer relief valves open, has been proposed as an accident management strategy to reduce risks by mitigating the severity of HPME. However, decay heat</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19790013525&hterms=molar+conductivity+iron+II&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dmolar%2Bconductivity%2Biron%2B%2528II%2529"><span id="translatedtitle"><span class="hlt">Core</span> formation, evolution, and convection: A geophysical model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ruff, L.; Anderson, D. L.</p> <p>1978-01-01</p> <p>A model is proposed for the formation and evolution of the Earth's <span class="hlt">core</span> which provides an adequate energy source for maintaining the geodynamo. A modified inhomogeneous accretion model is proposed which leads to initial iron and refractory enrichment at the center of the planet. The probable heat source for <span class="hlt">melting</span> of the <span class="hlt">core</span> is the decay of Al. The refractory material is emplaced irregularly in the lowermost mantle with uranium and thorium serving as a long lived heat source. Fluid motions in the <span class="hlt">core</span> are driven by the differential heating from above and the resulting cyclonic motions may be the source of the geodynamo.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014Litho.206..303B"><span id="translatedtitle">Microstructures and petrology of <span class="hlt">melt</span> inclusions in the anatectic sequence of Jubrique (Betic Cordillera, S Spain): Implications for crustal anatexis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barich, Amel; Acosta-Vigil, Antonio; Garrido, Carlos J.; Cesare, Bernardo; Taj?manová, Lucie; Bartoli, Omar</p> <p>2014-10-01</p> <p>We report a new occurrence of <span class="hlt">melt</span> inclusions in polymetamorphic granulitic gneisses of the Jubrique unit, a complete though strongly thinned crustal section located above the Ronda peridotite slab (Betic Cordillera, S Spain). The gneissic sequence is composed of mylonitic gneisses at the bottom and in contact with the peridotites, and porphyroblastic gneisses on top. Mylonitic gneisses are strongly deformed rocks with abundant garnet and rare biotite. Except for the presence of <span class="hlt">melt</span> inclusions, microstructures indicating the former presence of <span class="hlt">melt</span> are rare or absent. Upwards in the sequence, garnet decreases whereas biotite increases in modal proportion. <span class="hlt">Melt</span> inclusions are present from <span class="hlt">cores</span> to rims of garnets throughout the entire sequence. Most of the former <span class="hlt">melt</span> inclusions are now totally crystallized and correspond to nanogranites, whereas some of them are partially made of glass or, more rarely, are totally glassy. They show negative crystal shapes and range in size from ? 5 to 200 ?m, with a mean size of ? 30-40 ?m. Daughter phases in nanogranites and partially crystallized <span class="hlt">melt</span> inclusions include quartz, feldspars, biotite and muscovite; accidental minerals include kyanite, graphite, zircon, monazite, rutile and ilmenite; glass has a granitic composition. <span class="hlt">Melt</span> inclusions are mostly similar throughout all the gneissic sequence. Some fluid inclusions, of possible primary origin, are spatially associated with <span class="hlt">melt</span> inclusions, indicating that at some point during the suprasolidus history of these rocks granitic <span class="hlt">melt</span> and fluid coexisted. Thermodynamic modeling and conventional thermobarometry of mylonitic gneisses provide peak conditions of ? 850 °C and 12-14 kbar, corresponding to <span class="hlt">cores</span> of large garnets with inclusions of kyanite and rutile. Post-peak conditions of ? 800-850 °C and 5-6 kbar are represented by rim regions of large garnets with inclusions of sillimanite and ilmenite, cordierite-quartz-biotite coronas replacing garnet rims, and the matrix with oriented sillimanite. Previous conventional petrologic studies on these strongly deformed rocks have proposed that anatexis started during decompression from peak to post-peak conditions and in the field of sillimanite. The study of <span class="hlt">melt</span> inclusions shows, however, that <span class="hlt">melt</span> was already present in the system at peak conditions, and that most garnet grew in the presence of <span class="hlt">melt</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFM.V31E4810A"><span id="translatedtitle">Microstructures and Petrology of <span class="hlt">Melt</span> Inclusions in the Anatectic Sequence of Jubrique (Betic Cordillera, S Spain): Implications for Crustal Anatexis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Acosta-vigil, A.; Barich, A.; Garrido, C. J.; Cesare, B.; Taj?manová, L.; Bartoli, O.</p> <p>2014-12-01</p> <p>We report a new occurrence of <span class="hlt">melt</span> inclusions in polymetamorphic granulitic gneisses of the Jubrique unit, a complete though thinned crustal section located above the Ronda peridotite slab (Betic Cordillera, S Spain). The gneissic sequence is composed of mylonitic gneisses at the bottom and porphyroblastic gneisses on top. Mylonitic gneisses are strongly deformed rocks with abundant garnet and rare biotite. Except for the presence of <span class="hlt">melt</span> inclusions, microstructures indicating the former presence of <span class="hlt">melt</span> are rare or absent. Upwards in the sequence garnet decreases whereas biotite increases in proportion. <span class="hlt">Melt</span> inclusions are present from <span class="hlt">cores</span> to rims of garnets throughout the entire sequence. Most of the former <span class="hlt">melt</span> inclusions are now totally crystallized and correspond to nanogranites, whereas some of them are partially made of glass or, more rarely, are totally glassy. They show negative crystal shapes and range in size from ?5 to 200 micrometers, with a mean size of ?30-40 micrometers. Daughter phases in nanogranites and partially crystallized <span class="hlt">melt</span> inclusions include quartz, feldspars, biotite and muscovite; accidental minerals include kyanite, graphite, zircon, monazite, rutile and ilmenite; glass has a granitic composition. <span class="hlt">Melt</span> inclusions are mostly similar throughout all the gneissic sequence. Some fluid inclusions, of possible primary origin, are spatially associated with <span class="hlt">melt</span> inclusions, indicating that at some point during the suprasolidus history of these rocks granitic <span class="hlt">melt</span> and fluid coexisted. Thermodynamic modeling and conventional thermobarometry of mylonitic gneisses provide peak conditions of ?850 ºC and 12-14 kbar, corresponding to <span class="hlt">cores</span> of large garnets with inclusions of kyanite and rutile. Post-peak conditions of ?800-850 ºC and 5-6 kbar are represented by rim regions of large garnets with inclusions of sillimanite and ilmenite, cordierite-quartz-biotite coronas replacing garnet rims, and the matrix with oriented sillimanite. Previous conventional petrologic studies on these strongly deformed rocks have proposed that anatexis started during decompression from peak to post-peak conditions and in the field of sillimanite. The study of <span class="hlt">melt</span> inclusions shows, however, that <span class="hlt">melt</span> was already present in the system at peak conditions, and that most garnet grew in the presence of <span class="hlt">melt</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/541920"><span id="translatedtitle">Models and correlations of the DEBRIS Late-Phase <span class="hlt">Melt</span> Progression Model</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Schmidt, R.C.; Gasser, R.D. [Sandia National Labs., Albuquerque, NM (United States). Reactor Safety Experiments Dept.</p> <p>1997-09-01</p> <p>The DEBRIS Late Phase <span class="hlt">Melt</span> Progression Model is an assembly of models, embodied in a computer code, which is designed to treat late-phase <span class="hlt">melt</span> progression in dry rubble (or debris) regions that can form as a consequence of a severe <span class="hlt">core</span> uncover accident in a commercial light water nuclear reactor. The approach is fully two-dimensional, and incorporates a porous medium modeling framework together with conservation and constitutive relationships to simulate the time-dependent evolution of such regions as various physical processes act upon the materials. The objective of the code is to accurately model these processes so that the late-phase <span class="hlt">melt</span> progression that would occur in different hypothetical severe nuclear reactor accidents can be better understood and characterized. In this report the models and correlations incorporated and used within the current version of DEBRIS are described. These include the global conservation equations solved, heat transfer and fission heating models, <span class="hlt">melting</span> and refreezing models (including material interactions), liquid and solid relocation models, gas flow and pressure field models, and the temperature and compositionally dependent material properties employed. The specific models described here have been used in the experiment design analysis of the Phebus FPT-4 debris-bed fission-product release experiment. An earlier DEBRIS code version was used to analyze the MP-1 and MP-2 late-phase <span class="hlt">melt</span> progression experiments conducted at Sandia National Laboratories for the US Nuclear Regulatory Commission.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFMMR12A..04Z"><span id="translatedtitle">Sound velocities and <span class="hlt">melting</span> of Fe-Ni-Si system at high pressures under shock loading</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Y.; Sekine, T.; He, H.; Yu, Y.; Liu, F.; Zhang, M.</p> <p>2014-12-01</p> <p>The Earth's liquid outer <span class="hlt">core</span> is dominantly composed of iron and nickel (~5?10%), with a density lower by ~8% than that of the liquid iron at the <span class="hlt">core</span> conditions [e.g., 1], requiring the presence of light element(s) [e.g., 2]. Silicon, geochemically abundant, has long been considered as a major potential light element in the Earth's outer <span class="hlt">core</span> because of its high solubility in iron, iron-silicate interactions at <span class="hlt">core</span>-mantle boundary, the Si isotope data, and <span class="hlt">core</span> formation modeling [3]. To examine effects of Si on physical properties of Fe-Ni system, we directly measured densities, sound velocities, and <span class="hlt">melting</span> of Fe-9Ni-10Si (in weight percent) system up to ~280 GPa by shock experiments using a two-stage light-gas gun. The sound velocities were determined by the optical analyzer technique [4]. The results, compared with the seismic observations, show that silicon-rich liquid Fe-Ni system can satisfy the observed density deficit and seismological data simultaneously at the physical conditions of the outer <span class="hlt">core</span>. Analyses of the <span class="hlt">melting</span> temperatures of Fe-9Ni-10Si system imply the Fe-Ni-Si <span class="hlt">core</span> will be at lower temperatures by ~600?1000 K than the pure iron <span class="hlt">core</span> at ~330 GPa of the inner-<span class="hlt">core</span> boundary. [1]. Anderson, O. and D. Isaak, Another look at the <span class="hlt">core</span> density deficit of Earth's outer <span class="hlt">core</span>. Physics of the Earth and Planetary Interiors, 2002. 131(1): p. 19-27.[2]. Poirier, J.-P., Light elements in the Earth's outer <span class="hlt">core</span>: A critical review. Physics of the Earth and Planetary Interiors, 1994. 85(3): p. 319-337.[3]. Hirose, K., S. Labrosse, and J. Hernlund, Composition and State of the <span class="hlt">Core</span>. Annual Review of Earth and Planetary Sciences, 2013. 41: p. 657-691.[4]. Huang, H., et al., Evidence for an oxygen-depleted liquid outer <span class="hlt">core</span> of the Earth. Nature, 2011. 479(7374): p. 513-516.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014E%26PSL.399..103F"><span id="translatedtitle">Extreme mineral-scale Sr isotope heterogeneity in granites by disequilibrium <span class="hlt">melting</span> of the crust</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farina, Federico; Dini, Andrea; Rocchi, Sergio; Stevens, Gary</p> <p>2014-08-01</p> <p>The broadest ranges of initial Sr isotopic ratios (87Sr/86Sri) ever reported within a single igneous rock (?2×10-2) are preserved within the late Miocene laccolith-pluton-dyke felsic complex of Elba Island (Italy). For these units, the integration of textural and crystal-scale isotope data allows tracing the evolution of the 87Sr/86Sri of the <span class="hlt">melt</span> from the emplacement level back to the earliest pre-emplacement crystallization stage. The rock matrix minerals record the 87Sr/86Sri composition of the magma at the emplacement level (0.715-0.716). K-feldspar megacrysts, representing an earlier phase crystallized at depth, record a rim-to-<span class="hlt">core</span> increase of Sr-isotopic ratios from values similar to those of the matrix to significantly higher ones (?0.719). Remarkably, biotites hosted within megacrysts, representing the first crystallization stage, have extreme and contrasting 87Sr/86Sri values in the different intrusive units: biotites within megacrysts from the laccolith record the lowest ratio in the intrusive complex (?0.710), while those in the megacrysts from the pluton and associated felsic dyke have the highest 87Sr/86Sri(?0.732). This time-transgressive record of isotopic variation in the magma reflects episodic recharge and mixing of magma batches formed by disequilibrium <span class="hlt">melting</span> of crustal sources that produced <span class="hlt">melts</span> through different reactions as temperature was increasing. The progression from muscovite- to biotite-dominated fluid-absent <span class="hlt">melting</span> generates <span class="hlt">melts</span> with increasing 87Sr/86Sr, while at higher temperatures, the progression from biotite- to hornblende-dominated <span class="hlt">melting</span> reactions results in a decrease in the 87Sr/86Sr of the <span class="hlt">melt</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19800035221&hterms=earth+core&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dearth%2Bcore"><span id="translatedtitle"><span class="hlt">Core</span> cooling by subsolidus mantle convection. [thermal evolution model of earth</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schubert, G.; Cassen, P.; Young, R. E.</p> <p>1979-01-01</p> <p>Although vigorous mantle convection early in the thermal history of the earth is shown to be capable of removing several times the latent heat content of the <span class="hlt">core</span>, a thermal evolution model of the earth in which the <span class="hlt">core</span> does not solidify can be constructed. The large amount of energy removed from the model earth's <span class="hlt">core</span> by mantle convection is supplied by the internal energy of the <span class="hlt">core</span> which is assumed to cool from an initial high temperature given by the silicate <span class="hlt">melting</span> temperature at the <span class="hlt">core</span>-mantle boundary. For the smaller terrestrial planets, the iron and silicate <span class="hlt">melting</span> temperatures at the <span class="hlt">core</span>-mantle boundaries are more comparable than for the earth; the models incorporate temperature-dependent mantle viscosity and radiogenic heat sources in the mantle. The earth models are constrained by the present surface heat flux and mantle viscosity and internal heat sources produce only about 55% of the earth model's present surface heat flow.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015EGUGA..1710795S"><span id="translatedtitle">A benchmark initiative on mantle convection with <span class="hlt">melting</span> and <span class="hlt">melt</span> segregation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmeling, Harro; Dohmen, Janik; Wallner, Herbert; Noack, Lena; Tosi, Nicola; Plesa, Ana-Catalina; Maurice, Maxime</p> <p>2015-04-01</p> <p>In recent years a number of mantle convection models have been developed which include partial <span class="hlt">melting</span> within the asthenosphere, estimation of <span class="hlt">melt</span> volumes, as well as <span class="hlt">melt</span> extraction with and without redistribution at the surface or within the lithosphere. All these approaches use various simplifying modelling assumptions whose effects on the dynamics of convection including the feedback on <span class="hlt">melting</span> have not been explored in sufficient detail. To better assess the significance of such assumptions and to provide test cases for the modelling community we initiate a benchmark comparison. In the initial phase of this endeavor we focus on the usefulness of the definitions of the test cases keeping the physics as sound as possible. The reference model is taken from the mantle convection benchmark, case 1b (Blanckenbach et al., 1989), assuming a square box with free slip boundary conditions, the Boussinesq approximation, constant viscosity and a Rayleigh number of 1e5. <span class="hlt">Melting</span> is modelled assuming a simplified binary solid solution with linearly depth dependent solidus and liquidus temperatures, as well as a solidus temperature depending linearly on depletion. Starting from a plume free initial temperature condition (to avoid <span class="hlt">melting</span> at the onset time) three cases are investigated: Case 1 includes <span class="hlt">melting</span>, but without thermal or dynamic feedback on the convection flow. This case provides a total <span class="hlt">melt</span> generation rate (qm) in a steady state. Case 2 includes batch <span class="hlt">melting</span>, <span class="hlt">melt</span> buoyancy (<span class="hlt">melt</span> Rayleigh number Rm), depletion buoyancy and latent heat, but no <span class="hlt">melt</span> percolation. Output quantities are the Nusselt number (Nu), root mean square velocity (vrms) and qm approaching a statistical steady state. Case 3 includes two-phase flow, i.e. <span class="hlt">melt</span> percolation, assuming a constant shear and bulk viscosity of the matrix and various <span class="hlt">melt</span> retention numbers (Rt). These cases should be carried out using the Compaction Boussinseq Approximation (Schmeling, 2000) or the full compaction formulation. Variations of cases 1 - 3 may be tested, particularly studying the effect of <span class="hlt">melt</span> extraction. The motivation of this presentation is to summarize first experiences, suggest possible modifications of the case definitions and call interested modelers to join this benchmark exercise. References: Blanckenbach, B., Busse, F., Christensen, U., Cserepes, L. Gun¬kel, D., Hansen, U., Har¬der, H. Jarvis, G., Koch, M., Mar¬quart, G., Moore D., Olson, P., and Schmeling, H., 1989: A benchmark comparison for mantle convection codes, J. Geo¬phys., 98, 23 38. Schmeling, H., 2000: Partial <span class="hlt">melting</span> and <span class="hlt">melt</span> segregation in a convecting mantle. In: Physics and Chemistry of Partially Molten Rocks, eds. N. Bagdassarov, D. Laporte, and A.B. Thompson, Kluwer Academic Publ., Dordrecht, pp. 141 - 178.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/5611875"><span id="translatedtitle">TMI-2 <span class="hlt">core</span> damage: a summary of present knowledge</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Owen, D.E.; Mason, R.E.; Meininger, R.D.; Franz, W.A.</p> <p>1983-01-01</p> <p>Extensive fuel damage (oxidation and fragmentation) has occurred and the top approx. 1.5 m of the center portion of the TMI-2 <span class="hlt">core</span> has relocated. The fuel fragmentation extends outward to slightly beyond one-half the <span class="hlt">core</span> radius in the direction examined by the CCTV camera. While the radial extent of <span class="hlt">core</span> fragmentation in other directions was not directly observed, control and spider drop data and in-<span class="hlt">core</span> instrument data suggest that the <span class="hlt">core</span> void is roughly symmetrical, although there are a few indications of severe fuel damage extending to the <span class="hlt">core</span> periphery. The <span class="hlt">core</span> material fragmented into a broad range of particle sizes, extending down to a few microns. APSR movement data, the observation of damaged fuel assemblies hanging unsupported from the bottom of the reactor upper plenum structure, and the observation of once-molten stainless steel immediately above the active <span class="hlt">core</span> indicate high temperatures (up to at least 1720 K) extended to the very top of the <span class="hlt">core</span>. The relative lack of damage to the underside of the plenum structure implies a sharp temperature demarcation at the <span class="hlt">core</span>/plenum interface. Filter debris and leadscrew deposit analyses indicate extensive high temperature <span class="hlt">core</span> materials interaction, <span class="hlt">melting</span> of the Ag-In-Cd control material, and transport of particulate control material to the plenum and out of the vessel.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/51650742"><span id="translatedtitle">Impact <span class="hlt">Melt</span> Movement in Lunar Craters</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>V. J. Bray; L. L. Tornabene; C. Caudill; B. Rizk; A. S. McEwen; B. R. Hawke; T. A. Giguere; W. B. Garry; L. Kestay; C. H. van der Bogert; M. Robinson</p> <p>2010-01-01</p> <p>We are conducting mapping and analysis of small-scale flows, ponds and veneers in lunar craters to help us piece together the distribution, timing of emplacement, and cooling histories of different types of <span class="hlt">melt</span> deposits.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/19868865"><span id="translatedtitle">Isothermal compressibility in binary platinum based <span class="hlt">melts</span></span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>I G Kosnureva; M A Spiridonov; M M Mitko; V P Chentsov</p> <p>2008-01-01</p> <p>The method based on concentration dependences of density and formation heat values for determination of fluctuation structure factors and isothermal compressibility has been used for binary Pt-Si and Pt-Sn <span class="hlt">melts</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19850000069&hterms=ink&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dink"><span id="translatedtitle"><span class="hlt">Melt</span> Stirring by Horizontal Crucible Vibration</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wolf, M. F.; Elwell, D.; Feigelson, R. S.</p> <p>1985-01-01</p> <p>Horizontal vibration suggested as technique for more effective stirring of <span class="hlt">melts</span> in crystal-growth apparatus. Vibrational technique may replace accelerated crucible rotation. Potential superiority of vibrational technique shown by preliminary experiments in which ink stirred into water.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015MMTA..tmp..245P"><span id="translatedtitle">Analysis of <span class="hlt">Melt</span> Undercooling and Crystallization Kinetics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Perepezko, John H.; Hoffmeyer, Mark K.; De Cicco, Michael P.</p> <p>2015-05-01</p> <p>While <span class="hlt">melt</span> undercooling is often observed during solidification, the study of nucleation is challenging due to the numerous possible heterogeneous sites present in even high-purity <span class="hlt">melts</span>. Identification of active nucleation sites requires developing well-planned experimentation. In samples with well-defined and controlled undercooling the identification can be established for the active sites. The successful identification of nucleation sites reveals that there are a number of possible sites and mechanisms that can act to catalyze nucleation. The sites and mechanisms that have been identified involve primary phases developed during cooling of alloy <span class="hlt">melts</span>, liquid-added particle interfaces being modified (e.g., by adsorption or reaction) creating a particle type-independent nucleation potency, dissolved impurities precipitating out of the <span class="hlt">melt</span> at high undercoolings to catalyze nucleation, and nucleation sites resulting from residual solid preserved in cavities in inclusions or surface coatings.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2008AGUFM.C41D..02R"><span id="translatedtitle">Ice-shelf <span class="hlt">melting</span> around Antarctica</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rignot, E.; Jacobs, S.</p> <p>2008-12-01</p> <p>The traditional view on the mass balance of Antarctic ice shelves is that they loose mass principally from iceberg calving with bottom <span class="hlt">melting</span> a much lower contributing factor. Because ice shelves are now known to play a fundamental role in ice sheet evolution, it is important to re-evaluate their wastage processes from a circumpolar perspective using a combination of remote sensing techniques. We present area average rates deduced from grounding line discharge, snow accumulation, firn depth correction and ice shelf topography. We find that ice shelf <span class="hlt">melting</span> accounts for roughly half of ice-shelf ablation, with a total <span class="hlt">melt</span> water production of 1027 Gt/yr. The attrition fraction due to in-situ <span class="hlt">melting</span> varies from 9 to 90 percent around Antarctica. High <span class="hlt">melt</span> producers include the Ronne, Ross, Getz, Totten, Amery, George VI, Pine Island, Abbot, Dotson/Crosson, Shackleton, Thwaites and Moscow University Ice Shelves. Low producers include the Larsen C, Princess Astrid and Ragnhild coast, Fimbul, Brunt and Filchner. Correlation between <span class="hlt">melt</span> water production and grounding line discharge is low (R2 = 0.65). Correlation with thermal ocean forcing from the ocean are highest in the northern parts of West Antarctica where regressions yield R2 of 0.93-0.97. <span class="hlt">Melt</span> rates in the Amundsen Sea exhibit a quadratic sensitivity to thermal ocean forcing. We conclude that ice shelf <span class="hlt">melting</span> plays a dominant role in ice shelf mass balance, with a potential to change rapidly in response to altered ocean heat transport onto the Antarctic continental shelf.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/26517393"><span id="translatedtitle">Ash <span class="hlt">melting</span> behavior under coal gasification conditions</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Y. Ninomiya; A. Sato</p> <p>1997-01-01</p> <p>The results of this study show that CaCO3 additives are an efficient fluxing element for the control of ash <span class="hlt">melting</span>, more particularly Al2O3-rich ash <span class="hlt">melting</span>. The minimum values of the hemispherical temperatures of the ash-additive mixtures were 50–500 K lower than those of parent coal ashes. Empirical equations have been derived to relate ash fusion temperatures to ash composition. X-ray</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19850000339&hterms=MnBi&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DMnBi"><span id="translatedtitle">Damping <span class="hlt">Melt</span> Convection With A Magnetic Field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pirich, R. G.; Decarlo, J. L.</p> <p>1986-01-01</p> <p>Application of 3-kG magnetic field reduces thermal and solutal convection in Bi/MnBi <span class="hlt">melt</span> in Bridgman-Stockbarger (moving-vertical-thermalgradient) furnace operating in normal gravitational field. Resulting Bi/MnBi alloy samples had properties similar to samples grown under nearly zero gravity. New technique proves useful in growing more uniform, defect-free semiconductor materials from such other electrically conductive <span class="hlt">melts</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/22529078"><span id="translatedtitle">The <span class="hlt">melting</span> point of potassium superoxide</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>T. P. Firsova; A. N. Molodkina; T. G. Morozova; I. V. Aksenova</p> <p>1965-01-01</p> <p>Summary 1.The thermographic method was used to determine the <span class="hlt">melting</span> point of potassium Superoxide, which at atmospheric pressure lies between 490 and 530° for the different specimens. In vacuo, at a residual pressure of 1–2 mm, the <span class="hlt">melting</span> point of potassium Superoxide drops to 350–415°.2.A vigorous reaction between the molten potassium Superoxide and the glass is observed when the recording</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.springerlink.com/index/5x892u4410102l00.pdf"><span id="translatedtitle">Automatic <span class="hlt">melting</span> point determination of fats</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>W. G. Mertens; J. M. DeMan</p> <p>1972-01-01</p> <p>The Mettler FP3 automatic dropping point apparatus was used for the determination of <span class="hlt">melting</span> points of a variety of edible\\u000a fat products. The instrument was particularly suitable for this purpose because of the availability-of different heating rates.\\u000a Advantages were the fully automatic heating, the automatic and objective endpoint determination, the application for <span class="hlt">melted</span>\\u000a as well as solidified samples (shortening, margarine,</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/34615393"><span id="translatedtitle"><span class="hlt">Melting</span> points of synthetic wax esters</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>B. T. R. Iyengar; H. Schlenk</p> <p>1969-01-01</p> <p>Saturated, monoenoic and dienoic wax esters, C26?C40, have been synthesized from even-numbered fatty alcohols and acids. In homologous series of saturated esters, the increments\\u000a of <span class="hlt">melting</span> points follow a regular trend except for those esters which have an acid moiety two carbon atoms shorter than the\\u000a alcohol moiety. These wax esters have <span class="hlt">melting</span> points higher than interpolation would predict. Monoenoic</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/20726783"><span id="translatedtitle"><span class="hlt">Melting</span> of Dust Crystals by Single Particles</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ivanov, Yuriy; Melzer, Andre [Institut fuer Physik, Ernst-Moritz-Arndt-Universitaet Greifswald, 17489 Greifswald (Germany)</p> <p>2005-10-31</p> <p>The <span class="hlt">melting</span> transition of 2D finite dust clusters has been investigated. Therefore, a single dust particle was placed in a plane below the actual cluster plane. With reducing the gas pressure and with increase of the plasma power an instability due to the non-reciprocal attraction of the lower dust particle was excited that heats the cluster layer. The novel method of singular value decomposition (SVD) has been applied for the analysis of the cluster dynamics during <span class="hlt">melting</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/934458"><span id="translatedtitle">PURIFICATION OF IRIDIUM BY ELECTRON BEAM <span class="hlt">MELTING</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ohriner, Evan Keith [ORNL</p> <p>2008-01-01</p> <p>The purification of iridium metal by electron beam <span class="hlt">melting</span> has been characterized for 48 impurity elements. Chemical analysis was performed by glow discharge mass spectrographic (GDMS) analysis for all elements except carbon, which was analyzed by combustion. The average levels of individual elemental impurities in the starting powder varied from 37 g/g to 0.02 g/g. The impurity elements Li, Na, Mg, P, S, Cl, K, Ca, Mn, Co, Ni, Cu, Zn, As, Pd, Ag, Cd, Sn, Sb, Te, Ba, Ce, Tl, Pb, and Bi were not detectable following the purification. No significant change in concentration of the elements Ti, V, Zr, Nb, Mo, and Re was found. The elements B, C, Al, Si, Cr, Fe, Ru, Rh, and Pt were partially removed by vaporization during electron beam <span class="hlt">melting</span>. Langmuir's equation for ideal vaporization into a vacuum was used to calculate for each impurity element the expected ratio of impurity content after <span class="hlt">melting</span> to that before <span class="hlt">melting</span>. Equilibrium vapor pressures were calculated using Henry's law, with activity coefficients obtained from published data for the elements Fe, Ti, and Pt. Activity coefficients were estimated from enthalpy data for Al, Si, V, Cr, Mn, Co, Ni, Zr, Nb, Mo, and Hf and an ideal solution model was used for the remaining elements. The <span class="hlt">melt</span> temperature was determined from measured iridium weight loss. Excellent agreement was found between measured and calculated impurity ratios for all impurity elements. The results are consistent with some localized heating of the <span class="hlt">melt</span> pool due to rastering of the electron beam, with an average vaporization temperature of 3100 K as compared to a temperature of 2965 K calculated for uniform heating of the <span class="hlt">melt</span> pool. The results are also consistent with ideal mixing in the <span class="hlt">melt</span> pool.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2007AGUFM.G33B1242S"><span id="translatedtitle">Arctic Warming, Greenland <span class="hlt">Melt</span> and Moulins</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Steffen, K.; Huff, R.; Behar, A.</p> <p>2007-12-01</p> <p>Air temperatures on the Greenland ice sheet have increased by 4 deg. C since 1991. The ice sheet <span class="hlt">melt</span> area increased by 30% for the western part between 1979-2006, with record <span class="hlt">melt</span> years in 1987, 1991, 1998, 2002, 2005, and possibly the most extreme <span class="hlt">melt</span> year in 2007. The increasing trend in the total area of <span class="hlt">melting</span> bare ice is unmistakable at 13% per year, significant at a probability of 0.99. Hence, the bare ice region, the wet snow region, and the equilibrium line altitude have moved further inland and resulting in increased <span class="hlt">melt</span> water flux towards the coast. Warm and extended air temperatures are to blame for 1.5 m water equivalent surface reduction at the long-term equilibrium line altitude, 1100 m elevation at 70 deg. N during summer 2007. Increase in ice velocity in the ablation region and the concurrent increase in <span class="hlt">melt</span> water suggests that water penetrates to great depth through moulins and cracks, lubricating the bottom of the ice sheet. New insight was gained of subsurface hydrologic channels and cavities using new instrumentation and a video system during the <span class="hlt">melt</span> peak in August 2007. Volume and geometry of a 100 m deep moulin were mapped with a rotating laser, and photographs with digital cameras. Sub-glacial hydrologic channels were investigated and filmed using a tethered, autonomous system, several hundred meters into the ice. These new results will be discussed in view of the rapid increase in <span class="hlt">melt</span> area and mass loss of the Greenland ice sheet due to increasing air temperatures.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19730039853&hterms=fracture+initiation&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dfracture%2Binitiation"><span id="translatedtitle">On the initiation of <span class="hlt">melt</span> fracture.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mcintire, L. V.</p> <p>1972-01-01</p> <p>Discussion of a problem encountered in the processing of viscoelastic materials that is caused by the presence of a hydrodynamic instability in the extrusion of polymer <span class="hlt">melts</span>. The importance of the so-called Weissenberg number in determining the onset of the <span class="hlt">melt</span> fracture is examined using classical linearized hydrodynamic stability analysis. It is shown that the simple shearing flow of a viscoelastic fluid becomes unstable at a critical value of the Weissenberg number. Implications for the extrusion processing of polymers are reviewed.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/20875649"><span id="translatedtitle">Behavior of metals in ash <span class="hlt">melting</span> and gasification-<span class="hlt">melting</span> of municipal solid waste (MSW)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Jung, C.H. [Laboratory of Solid Waste Disposal Engineering, Graduate School of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628 (Japan); Matsuto, T. [Laboratory of Solid Waste Disposal Engineering, Graduate School of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628 (Japan)]. E-mail: matsuto@eng.hokudai.ac.jp; Tanaka, N. [Laboratory of Solid Waste Disposal Engineering, Graduate School of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628 (Japan)</p> <p>2005-07-01</p> <p>In this study, metal behavior in ash-<span class="hlt">melting</span> and municipal solid waste (MSW) gasification-<span class="hlt">melting</span> facilities were investigated. Eight ash-<span class="hlt">melting</span> and three MSW gasification-<span class="hlt">melting</span> facilities with a variety of <span class="hlt">melting</span> processes and feedstocks were selected. From each facility, <span class="hlt">melting</span> furnace fly ash (MFA) and molten slag were sampled, and feedstock of the ash-<span class="hlt">melting</span> processes was also taken. For the ash <span class="hlt">melting</span> process, the generation rate of MFA was well correlated with the ratio of incineration fly ash (IFA) in feedstock, and this was because MFA was formed mostly by mass transfer from IFA and a limited amount from bottom ash (BA). Distribution ratios of metal elements to MFA were generally determined by volatility of the metal element, but chlorine content in feedstock had a significant effect on Cu and a marginal effect on Pb. Distribution ratio of Zn to MFA was influenced by the oxidizing atmosphere in the furnace. High MFA generation and distribution ratio of non-volatile metals to MFA in gasification-<span class="hlt">melting</span> facilities was probably caused by carry-over of fine particles to the air pollution control system due to large gas volume. Finally, dilution effect was shown to have a significant effect on metal concentration in MFA.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFMMR31A4310Z"><span id="translatedtitle"><span class="hlt">Melting</span> of Fe and Fe0.9Ni0.1 alloy at high pressures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, D.; Jackson, J. M.; Zhao, J.; Sturhahn, W.; Alp, E. E.; Hu, M. Y.; Toellner, T.</p> <p>2014-12-01</p> <p>Cosmochemical studies suggest that the <span class="hlt">cores</span> of terrestrial planets are primarily composed of Fe alloyed with about 5 to 10 wt% Ni, plus some light elements (e.g., McDonough and Sun 1995). Thus, the high pressure <span class="hlt">melting</span> curve of Fe0.9Ni0.1 is considered to be an important reference for characterizing the <span class="hlt">cores</span> of terrestrial planets. We have determined the <span class="hlt">melting</span> points of fcc-structured Fe and Fe0.9Ni0.1 up to 86 GPa using an in-situ method that monitors the atomic dynamics of the Fe atoms in the sample, synchrotron Mössbauer spectroscopy (Jackson et al. 2013). A laser heated diamond anvil cell is used to provide the high pressure-high temperature environmental conditions, and in-situ X-ray diffraction is used to constrain the pressure of the sample. To eliminate the influence of temperature fluctuations experienced by the sample on the determination of <span class="hlt">melting</span>, we develop a Fast Temperature Readout (FasTeR) spectrometer. The FasTeR spectrometer features a fast reading rate (>100 Hz), a high sensitivity, a large dynamic range and a well-constrained focus. By combining the <span class="hlt">melting</span> curve of fcc-structured Fe0.9Ni0.1 alloy determined in our study and the fcc-hcp phase boundary from Komabayashi et al. (2012), we calculate the fcc-hcp-liquid triple point of Fe0.9Ni0.1. Using this triple point and the thermophysical parameters from a nuclear resonant inelastic X-ray scattering study on hcp-Fe (Murphy et al. 2011), we compute the <span class="hlt">melting</span> curve of hcp-structured Fe0.9Ni0.1. We will discuss our new experimental results with implications for the <span class="hlt">cores</span> of Venus, Earth and Mars. Select references: McDonough & Sun (1995): The composition of the Earth. Chem. Geol. 120, 223-253. Jackson et al. (2013): <span class="hlt">Melting</span> of compressed iron by monitoring atomic dynamics, EPSL, 362, 143-150. Komabayashi et al. (2012): In situ X-ray diffraction measurements of the fcc-hcp phase transition boundary of an Fe-Ni alloy in an internally heated diamond anvil cell, PCM, 39, 329-338. Murphy et al. (2011): <span class="hlt">Melting</span> and thermal pressure of hcp-Fe from the phonon density of states, PEPI, 188, 114-120.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19930005199&hterms=current+driven+electrostatic+electromagnetic+instabilities&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dcurrent%2Bdriven%2Belectrostatic%2Belectromagnetic%2Binstabilities"><span id="translatedtitle">Volcanism by <span class="hlt">melt</span>-driven Rayleigh-Taylor instabilities and possible consequences of <span class="hlt">melting</span> for admittance ratios on Venus</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tackley, P. J.; Stevenson, D. J.; Scott, D. R.</p> <p>1992-01-01</p> <p>A large number of volcanic features exist on Venus, ranging from tens of thousands of small domes to large shields and coronae. It is difficult to reconcile all these with an explanation involving deep mantle plumes, since a number of separate arguments lead to the conclusion that deep mantle plumes reaching the base of the lithosphere must exceed a certain size. In addition, the fraction of basal heating in Venus' mantle may be significantly lower than in Earth's mantle reducing the number of strong plumes from the <span class="hlt">core</span>-mantle boundary. In three-dimensional convection simulations with mainly internal heating, weak, distributed upwellings are usually observed. We present an alternative mechanism for such volcanism, originally proposed for the Earth and for Venus, involving Rayleigh-Taylor instabilities driven by <span class="hlt">melt</span> buoyancy, occurring spontaneously in partially or incipiently molten regions.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1993LPI....24...35A"><span id="translatedtitle">Descriptions and preliminary interpretations of <span class="hlt">cores</span> recovered from the Manson Impact Structure (Iowa)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anderson, R. R.; Witzke, B. J.; Hartung, J. B.; Shoemaker, E. M.; Roddy, D. J.</p> <p>1993-03-01</p> <p>A <span class="hlt">core</span> drilling program initiated by the Iowa Geological Survey Bureau and U.S. Geological Survey in 1991 and 1992 collected 12 <span class="hlt">cores</span> totalling over 1200 m from the Manson Impact Structure, a probable K-T boundary structure located in north-central Iowa. <span class="hlt">Cores</span> were recovered from each of the major structural terranes, with 2 <span class="hlt">cores</span> (M-3 and M-4) from the Terrace Terrane, 4 <span class="hlt">cores</span> (M-2, M-2A, M-6, and M-9) from the Crater Moat, and 6 <span class="hlt">cores</span> (M-1, M-5, M-7, M-8, M-10, and M-11) from the Central Peak. These supplemented 2 central peak <span class="hlt">cores</span> (1-A and 2-A) drilled in 1953. The <span class="hlt">cores</span> penetrated five major impact lithologies: (1) sedimentary clast breccia; (2) impact ejecta; (3) central peak crystallite rocks; (4) crystalline clast breccia with sandy matrix; and (5) crystallite clast breccia with a <span class="hlt">melt</span> matrix. Descriptions and preliminary interpretations of these <span class="hlt">cores</span> are presented.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/41980567"><span id="translatedtitle"><span class="hlt">Melting</span> relations in the iron-sulfur system at ultra-high pressures - Implications for the thermal state of the earth</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Quentin Williams; Raymond Jeanloz</p> <p>1990-01-01</p> <p>The <span class="hlt">melting</span> temperatures of FeS-troilite and of a 10-wt-pct sulfur iron alloy have been measured to pressures of 120 and 90 GPa, respectively. The results document that FeS <span class="hlt">melts</span> at a temperature of 4100 (+ or - 300) K at the pressure of the <span class="hlt">core</span>-mantle boundary. Eutecticlike behavior persists in the iron-sulfur system to the highest pressures of measurements, in</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60052591"><span id="translatedtitle">Ultra slow EB <span class="hlt">melting</span> to reduce reactor cladding</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>S. A. Worcester; C. R. Woods; G. S. Galer; R. L. Propst</p> <p>1989-01-01</p> <p>A process is described for making an electron beam <span class="hlt">melted</span> fuel element liner material from sponge zirconium, the process comprising: electron beam <span class="hlt">melting</span> sponge zirconium at a <span class="hlt">melting</span> rate of less than 1 inch per hour to form an electron beam <span class="hlt">melted</span> zirconium material containing less than 300 ppm iron, less than 400 ppm oxygen, and less than 5 ppm</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.lps.ens.fr/~caupin/fichiersPDF/PRB_2008_77_184108_1-7.pdf"><span id="translatedtitle"><span class="hlt">Melting</span> and freezing of embedded nanoclusters Frdric Caupin*</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Caupin, Frédéric</p> <p></p> <p>. Nanocrystals NCs often <span class="hlt">melt</span> at temperatures lower than the bulk <span class="hlt">melting</span> point T0, and the smaller the size, the larger the <span class="hlt">melting</span> point shift.2 This holds for most freestanding or supported NCs, which are in contact with their vapor. However, when NCs are embedded in another material, the <span class="hlt">melting</span> point can be elevated</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.public.iastate.edu/~xsong/paper/xs_19.pdf"><span id="translatedtitle">The <span class="hlt">melting</span> lines of model systems calculated from coexistence simulations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Song, Xueyu</p> <p></p> <p>with both phases will evolve toward the equilibrium <span class="hlt">melting</span> point. Typically, the system evolvesThe <span class="hlt">melting</span> lines of model systems calculated from coexistence simulations James R. Morrisa) Metal the equilibrium <span class="hlt">melting</span> curve. The coexisting systems evolve rapidly toward the <span class="hlt">melting</span> temperature. The P</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19630000086&hterms=fiber+channel&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dfiber%2Bchannel"><span id="translatedtitle">Integral coolant channels supply made by <span class="hlt">melt</span>-out method</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Escher, W. J. D.</p> <p>1964-01-01</p> <p><span class="hlt">Melt</span>-out method of constructing strong, pressure-tight fluid coolant channels for chambers is accomplished by cementing pins to the surface and by depositing a <span class="hlt">melt</span>-out material on the surface followed by two layers of epoxy-resin impregnated glass fibers. The structure is heated to <span class="hlt">melt</span> out the low-<span class="hlt">melting</span> alloy.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/781684"><span id="translatedtitle">Risk assessment of K basin twelve-inch drain valve failure from a <span class="hlt">postulated</span> seismic initiating event</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>MORGAN, R.G.</p> <p>1999-04-06</p> <p>The Spent Nuclear Fuel (SNF) Project will transfer metallic SNF from the Hanford 105 K-East and 105 K-West Basins to safe interim storage in the Canister Storage Building in the 200 Area. The initial basis for design, fabrication, installation, and operation of the fuel removal systems was that the basin leak rates which could result from a <span class="hlt">postulated</span> accident condition would not be excessive relative to reasonable recovery operations. However, an additional potential K Basin water leak path is through the K Basin drain valves. Three twelve-inch drain valves are located in the main basin bays along the north wall. The sumps containing the valves are filled with concrete which covers the drain valve body. Visual observations suggest that only the valve's bonnet and stem are exposed above the basin concrete floor. It was recognized, however, that damage of the drain valve bonnet or stem during a seismic initiating event could provide a potential K Basin water leak path. The objectives of this activity are to: (1) evaluate the risk of damaging the three twelve-inch drain valves located along the north wall of the main basin from a seismic initiating event, and (2) determine the associated potential leak rate from a damaged valve.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/0812.1148v4"><span id="translatedtitle">The Invariant Set <span class="hlt">Postulate</span>: A New Geometric Framework for the Foundations of Quantum Theory and the Role Played by Gravity</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>T. N. Palmer</p> <p>2009-06-30</p> <p>A new law of physics is proposed, defined on the cosmological scale but with significant implications for the microscale. Motivated by nonlinear dynamical systems theory and black-hole thermodynamics, the Invariant Set <span class="hlt">Postulate</span> proposes that cosmological states of physical reality belong to a non-computable fractal state-space geometry I, invariant under the action of some subordinate deterministic causal dynamics. An exploratory analysis is made of a possible causal realistic framework for quantum physics, based on key properties of I. For example, sparseness is used to relate generic counterfactual states to points not lying on I, thus providing a geometric basis for the essential contextuality of quantum physics and the role of the abstract Hilbert Space in quantum theory. Also, self-similarity, described in a symbolic setting, provides a possible "realistic" perspective on the essential role of complex numbers and quaternions in quantum theory. A new interpretation is given to the standard "mysteries" of quantum theory: superposition, measurement, nonlocality, emergence of classicality and so on. It is proposed that heterogeneities in the fractal geometry of I are manifestations of the phenomenon of gravity. Since quantum theory is inherently blind to the existence of such state-space geometries, the analysis here suggests that attempts to formulate unified theories of physics within a conventional quantum-theoretic framework are misguided, and that a successful quantum theory of gravity should unify the causal non-Euclidean geometry of space time with the atemporal fractal geometry of state space.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2005IJMPD..14.2095R"><span id="translatedtitle">An Ambiguous Statement Called the "tetrad <span class="hlt">Postulate</span>" and the Correct Field Equations Satisfied by the Tetrad Fields</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rodrigues, Waldyr A.; Souza, Quintino A. G.</p> <p></p> <p>The names tetrad, tetrads, cotetrads have been used with many different meanings in the physics literature, not all of them equivalent from the mathematical point of view. In this paper, we introduce unambiguous definitions for each of those terms, and show how the old miscellanea made many authors introduce in their formalism an ambiguous statement called the "tetrad <span class="hlt">postulate</span>," which has been the source of much misunderstanding, as we show explicitly by examining examples found in the literature. Since formulating Einstein's field equations intrinsically in terms of cotetrad fields ?a, a = 0, 1, 2, 3 is a worthy enterprise, we derive the equation of motion of each ?a using modern mathematical tools (the Clifford bundle formalism and the theory of the square of the Dirac operator). Indeed, we identify (giving all details and theorems) from the square of the Dirac operator some noticeable mathematical objects, namely, the Ricci, Einstein, covariant D'Alembertian and the Hodge Laplacian operators, which permit us to show that each ?a satisfies a well-defined wave equation. Also, we present for completeness a detailed derivation of the cotetrad wave equations from a variational principle. We compare the cotetrad wave equation satisfied by each ?a with some others appearing in the literature, and which are unfortunately in error.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2007AGUFMDI42A..07T"><span id="translatedtitle">Hydrous Partial <span class="hlt">Melting</span> of the Upper Mantle as Judged From Mineral/<span class="hlt">Melt</span> Partition Coefficients.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tenner, T. J.; Hirschmann, M.; Aubaud, C.; Withers, A. C.</p> <p>2007-12-01</p> <p>It has been known for more than 10 years that nominally anhydrous minerals may incite small amounts of <span class="hlt">melting</span> in Earth's mantle. In recent years, there has been a great increase in experimental data on the H2O storage capacity of nominally anhydrous minerals. Yet, disagreement among models for the locus of dehydration <span class="hlt">melting</span> in the upper mantle is growing rather than narrowing. Models span the gamut from requiring small amounts of hydrous <span class="hlt">melt</span> throughout the upper mantle, to hydrous <span class="hlt">melting</span> in a global low velocity zone layer at depths of ~80-200 km, to <span class="hlt">melting</span> only beneath ridges and oceanic islands in a restricted interval a few 10s of km beneath the locus of dry <span class="hlt">melting</span>. These disagreements persist because direct experimental investigations of the influence of small amounts of H2O on mantle <span class="hlt">melting</span> are not feasible, and consequently understanding comes from parameterization of indirect experimental constraints. One key constraint on the possible locus of hydrous <span class="hlt">melting</span> in the upper mantle is the range of feasible concentrations of H2O in near-solidus hydrous <span class="hlt">melts</span>. For a mantle with a fixed amount of H2O, Cmantle, the maximum H2O concentration of an incipient partial <span class="hlt">melt</span> is given by Cmantle/Dperid/<span class="hlt">melt</span>, where Dperid/<span class="hlt">melt</span> is the equilibrium bulk partition coefficient between the peridotite mineral residue and the partial <span class="hlt">melt</span>. To address this issue, we conducted experimental determinations of Dmineral/<span class="hlt">melt</span> for upper mantle minerals (garnet, cpx, opx) from 3 to 5 GPa using piston cylinder and multi-anvil devices. For minerals, concentrations of H2O were determined using low-blank SIMS techniques; for glasses, concentrations were determined by SIMS, FTIR, electron microprobe totals, and confocal Raman spectroscopy. Values for Dgarnet/<span class="hlt">melt</span> span a wide range, and are apparently controlled by the concentration of minor elements in garnet, notably TiO2. Finally, values for Dpyx/<span class="hlt">melt</span> depend strongly on the concentration of Al in pyroxene, and in particular on the abundance of tetrahedral Al in pyroxene. Combining experimental constraints on Dmineral/<span class="hlt">melt</span> with the modal proportions and compositions of minerals near the peridotite solidus, it is possible to estimate the H2O concentration of incipient partial <span class="hlt">melts</span>. For mantle with 100 ppm H2O, such partial <span class="hlt">melts</span> have 1.2 wt.% H2O at 3 GPa and 2.3 wt.% at 7 GPa. Such modest concentrations of H2O provide only small stabilization of <span class="hlt">melt</span> relative to a dry peridotite system, thereby supporting the inference that dehydration partial <span class="hlt">melting</span> of normal mantle is feasible only near where the dry peridotite solidus is approached, meaning immediately below the locus of dry <span class="hlt">melting</span> beneath ridges and mantle plumes.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013AGUFMMR13B..03C"><span id="translatedtitle"><span class="hlt">Melting</span> and Phase Relations in the FeO-FeS System at High Pressure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Campbell, A. J.; Reaman, D. M.; Fischer, R. A.; Chidester, B.; Myers, G.; Heinz, D. L.; Prakapenka, V.</p> <p>2013-12-01</p> <p>Terrestrial planetary <span class="hlt">cores</span>, like that of the Earth, are composed of iron alloys with light elements such as O, S, Si, and/or C, and therefore the phase relations of these iron-rich systems are essential to understanding the structure, composition, and evolution of planetary <span class="hlt">cores</span>. Binary Fe-X phase diagrams are largely established up to approximately Earth's <span class="hlt">core</span>-mantle boundary pressures at least, but the relevant ternary and higher order phase equilibria are less well understood. Here we present phase relations, including <span class="hlt">melting</span>, on the FeO-FeS join to better constrain the Fe-FeO-FeS system that may be important to planetary <span class="hlt">cores</span>, including Earth's. We performed synchrotron X-ray diffraction experiments to monitor the phases present in FeO:FeS mixtures up to 60 GPa and >2500 K. A basic result is that FeO and FeS do coexist at high pressures and temperatures, with no evidence of a new phase forming between the two. At pressures near 46 GPa the eutectic composition lies on the FeS-rich side of this binary, as indicated by the loss of FeS diffraction and persistence of FeO diffraction in a 1:1 FeO:FeS mixture. <span class="hlt">Melting</span> in the FeO-FeS binary at high pressures occurs at temperatures within ~100-200 K of the FeS <span class="hlt">melting</span> curve [1]. Building upon earlier work on the structural (e.g., [1,2]) and binary <span class="hlt">melting</span> (e.g., [3,4]) behavior in the Fe-FeS and Fe-FeO systems, these results help define the ternary Fe-FeO-FeS system under P,T conditions relevant to terrestrial planetary <span class="hlt">cores</span>. In particular, the P,T conditions of the Martian <span class="hlt">core</span> are covered by this study, and the FeO-FeS system may be especially relevant there because of its high mantle FeO content and its low <span class="hlt">core</span> density, suggesting a relatively high sulfur content. [1] Reaman et al., AGU Fall Meeting 2012. [2] Fischer et al., Geophys. Res. Lett. 38, L24301, 2011. [3] Campbell et al., Phys. Earth Planet. Int. 162, 119-128, 2007. [4] Seagle et al., Earth Planet. Sci. Lett. 265, 655-665, 2008.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2012Nanos...4.4702H"><span id="translatedtitle">Direct observation of <span class="hlt">melting</span> behaviors at the nanoscale under electron beam and heat to form hollow nanostructures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huang, Chun-Wei; Hsin, Cheng-Lun; Wang, Chun-Wen; Chu, Fu-Hsuan; Kao, Chen-Yen; Chen, Jui-Yuan; Huang, Yu-Ting; Lu, Kuo-Chang; Wu, Wen-Wei; Chen, Lih-Juann</p> <p>2012-07-01</p> <p>We report the <span class="hlt">melting</span> behaviours of ZnO nanowire by heating ZnO-Al2O3 <span class="hlt">core</span>-shell heterostructures to form Al2O3 nanotubes in an in situ ultrahigh vacuum transmission electron microscope (UHV-TEM). When the ZnO-Al2O3 <span class="hlt">core</span>-shell nanowire heterostructures were annealed at 600 °C under electron irradiation, the amorphous Al2O3 shell became single crystalline and then the ZnO <span class="hlt">core</span> <span class="hlt">melted</span>. The average vanishing rate of the ZnO <span class="hlt">core</span> was measured to be 4.2 nm s-1. The thickness of the Al2O3 nanotubes can be precisely controlled by the deposition process. Additionally, the inner geometry of nanotubes can be defined by the initial ZnO <span class="hlt">core</span>. The result shows a promising method to obtain the biocompatible Al2O3 nanotubes, which may be applied in drug delivery, biochemistry and resistive switching random access memory (ReRAM).We report the <span class="hlt">melting</span> behaviours of ZnO nanowire by heating ZnO-Al2O3 <span class="hlt">core</span>-shell heterostructures to form Al2O3 nanotubes in an in situ ultrahigh vacuum transmission electron microscope (UHV-TEM). When the ZnO-Al2O3 <span class="hlt">core</span>-shell nanowire heterostructures were annealed at 600 °C under electron irradiation, the amorphous Al2O3 shell became single crystalline and then the ZnO <span class="hlt">core</span> <span class="hlt">melted</span>. The average vanishing rate of the ZnO <span class="hlt">core</span> was measured to be 4.2 nm s-1. The thickness of the Al2O3 nanotubes can be precisely controlled by the deposition process. Additionally, the inner geometry of nanotubes can be defined by the initial ZnO <span class="hlt">core</span>. The result shows a promising method to obtain the biocompatible Al2O3 nanotubes, which may be applied in drug delivery, biochemistry and resistive switching random access memory (ReRAM). Electronic supplementary information (ESI) available: Proof of the electron irradiation effect and three in situ TEM videos as dynamic observation of the ZnO-Al2O3 <span class="hlt">core</span>-shell nanowire heterostructures forming the Al2O3 nanotube at 600 °C under electron irradiation and the disappearance of the ZnO <span class="hlt">core</span>. See DOI: 10.1039/c2nr30724c</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFMDI53C..02W"><span id="translatedtitle">Physical mechanisms of planetary <span class="hlt">core</span> formation: Constraints from in-situ X-ray microtomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Watson, H. C.; Van Deusen, J.; Shi, K.; Yu, T.; Wang, Y.</p> <p>2014-12-01</p> <p>Segregation of the metallic <span class="hlt">core</span> from a silicate mantle is a crucial aspect of early planetary evolution. Although a magma ocean scenario is often used to explain differentiation of large planets such as Earth, smaller planets and planetesimals likely never achieved the high temperatures necessary for wide scale <span class="hlt">melting</span>. In these smaller bodies, silicates may have only partially <span class="hlt">melted</span>, or not <span class="hlt">melted</span> at all. Furthermore, isotopic signatures in meteorites suggest that some planetesimals differentiated within just a few million years. Achieving <span class="hlt">core</span> segregation on this time scale whereby <span class="hlt">core</span> material drains through a solid silicate mantle via an interconnected network of <span class="hlt">melt</span> faces two major problems: (1) in a hydrostatic situation, the percolation threshold is above 5 vol% <span class="hlt">melt</span>, so the process would lead to inefficient <span class="hlt">core</span> formation, and (2) the permeability of fully connected <span class="hlt">melts</span> at microstructural equilibrium is low enough that some planetesimals may still not be able to differentiate on this short time scale. It has been suggested that shear deformation can cause isolated <span class="hlt">melt</span> pockets to become connected even at low <span class="hlt">melt</span> fractions. Here, we have measured the change in permeability of <span class="hlt">core</span> forming <span class="hlt">melts</span> in solid silicate and partially molten silicate matrix due to deformation. Mixtures of olivine or KLB-1 peridotite and FeS close to the equilibrium percolation threshold (~5 vol% FeS) were pre-synthesized to achieve an equilibrium microstructure, and then loaded into the high pressure X-ray tomography apparatus at GSECARS, sector 13-BMD, at the Advanced Photon Source (Argonne National Laboratory). The samples were then pressed to ~2GPa, and heated to ~1100°C. Alternating cycles of rotation to collect X-ray tomography images, and twisting to deform the sample were conducted. Starting materials and run products have also been analysed at high resolution in three dimensions using FIB/SEM cross-beam tools. Quantitative analyses have been performed on the resulting 3-dimensional x-ray tomographic images to evaluate the effect of shear deformation on permeability of <span class="hlt">core</span> forming <span class="hlt">melts</span>, and place constraints on the timing of <span class="hlt">core</span> formation in smaller terrestrial planets and planetesimals.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://nanoscience.bu.edu/papers/Faul-Contrasting%20viscoelastic%20behavior....-missing.pdf"><span id="translatedtitle">Materials Science and Engineering A 442 (2006) 170174 Contrasting viscoelastic behavior of <span class="hlt">melt</span>-free and <span class="hlt">melt</span>-bearing olivine</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p>2006-01-01</p> <p>-free and <span class="hlt">melt</span>-bearing olivine: Implications for the nature of grain-boundary sliding Ian Jacksona,, Ulrich H Abstract <span class="hlt">Melt</span>-free and basaltic (complex alumino-silicate) <span class="hlt">melt</span>-bearing specimens of fine oscillation and microcreep, display markedly different behavior. For the <span class="hlt">melt</span>-bearing materials, superimposed</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://people.bu.edu/ufaul/UPubs/JacksonMSEA06.pdf"><span id="translatedtitle">Materials Science and Engineering A 442 (2006) 170174 Contrasting viscoelastic behavior of <span class="hlt">melt</span>-free and <span class="hlt">melt</span>-bearing olivine</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p>2006-01-01</p> <p>-free and <span class="hlt">melt</span>-bearing olivine: Implications for the nature of grain-boundary sliding Ian Jacksona,, Ulrich H bstract <span class="hlt">Melt</span>-free and basaltic (complex alumino-silicate) <span class="hlt">melt</span>-bearing specimens of fine oscillation and microcreep, display markedly different behavior. For the <span class="hlt">melt</span>-bearing aterials, superimposed</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1995Metic..30S.577S"><span id="translatedtitle">Shock-<span class="hlt">Melted</span> Regions in the Krymka (LL3) Chondrite</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Semenenko, V. P.; Perron, C.</p> <p>1995-09-01</p> <p>Shock effects of various intensities are common in all kinds of meteorites, but, in ordinary chondrites, the most severe ones are observed mostly in metamorphosed chondrites (petrologic types 5 and 6), and they are rare in type 3 [1]. However, we report here observations of strong shock effects in a specimen of the Krymka (LL3.1/S3) chondrite, one of the three most primitive ordinary chondrites. Examination of various samples of Krymka in the Ukrainian meteorite collection has already revealed evidences of shock effects, indicative of pressures of 25-45 GPa (assuming non-porous material) and temperatures <= 500 degrees C, with local excursions to >=988 degrees C (<span class="hlt">melting</span> of Fe-FeS eutectic) [2]. Sample N1290/29 (134 g), from the same collection, contains light-colored, friable, completely <span class="hlt">melted</span> zones. Observations were made on 6 polished sections from that specimen, with a total area of 14 cm2. In 4 of these, 4 <span class="hlt">melted</span> regions occupy a total of ~3 cm2. They are chondrule-free and consist of porphyritic and skeletal silicates (mainly olivine) in a cryptocrystalline mesostasis, along with metal-troilite mixtures with dendritic and cellular structures. Olivine composition is variable (Fa(sub)10-26) but to a lesser extent than in Krymka chondrules (Fa(sub)0-35). The mesostasis is also inhomogeneous. Apart from a few notable exceptions, olivine crystals are normally zoned, with FeO increasing from <span class="hlt">core</span> to rim. Fe-Ni cells are zoned as well, consisting of a <span class="hlt">core</span> with 11.2-22.6 wt%Ni and 0.83-0.96 wt%Co (probably martensite), and a Ni-rich rim (up to 51.3 wt%Ni, probably tetrataenite). The metal contains P (0.12-0.43 wt%), which seems to be, at least in part, in tiny schreibersite inclusions, and the troilite contains Ni (0.05- 4.2 wt%Ni). Metal-troilite mixtures contain abundant globules (up to 15 microns in diameter) of a Fe-Na phosphate (maybe maricite). These globules are usually rimmed with numerous euhedral micrometer-sized chromites. Larger euhedral chromites also occur isolated in metal-troilite. The <span class="hlt">melted</span> regions are surrounded by a transition zone with chondritic texture, containing completely <span class="hlt">melted</span> troilite and partially <span class="hlt">melted</span> metal. The highly variable Co concentration (0.2-13.0 wt%) of the metal grains in this zone reflects the high degree of unequilibration of the Krymka chondrite. Shock pressure in the range 75-90 GPa is normally required to induce local complete <span class="hlt">melting</span> of chondritic matter, but, in the present case, pressure as low as 30 GPa may be responsible for the observed effects, because of the porous nature of type 3 material [1]. In any case, the temperature must have been larger than 1450 degrees C. Experimental data on zoning trends in olivine [3] and Ni content in troilite [4] suggest a cooling rate of at least 100 degrees C/h. The association of P and Cr with metal-troilite reflects their association with metal in the host: Ca- phosphates are common at the boundaries of Krymka metal grains and many of these contain myriads of tiny chromites [5]. P and Cr were probably reduced at high temperature and they dissolved in metal-troilite liquid. Upon cooling, they reoxidized and crystallised. The unusual phosphate may result from higher volatility and mobility of Na relative to Ca. Mechanical deformations (shear) of some of these phosphate globules and of <span class="hlt">melted</span> troilite attest that, after complete solidification of the <span class="hlt">melted</span> regions, Krymka was subjected to other, less intense shock(s). References: [1] St"ffler D. et al. (1991) GCA, 55, 3845. [2] Semenenko V. P. et al. (1987) The Meteorites of Ukraine, 218 pp., Naukova Dumka (in Russian). [3] Radomsky P. M. and Hewins R. H. (1990) GCA, 54, 3475. [4] Smith B. A. and Goldstein J. I. (1977) GCA, 41, 1061. [5] Perron C. and Bourot-Denise M. (1992) LPS XXIII, 1055.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19800039446&hterms=howardite&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dhowardite"><span id="translatedtitle">Origin of impact <span class="hlt">melt</span> rocks in the Bununu howardite</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Klein, L. C.; Hewins, R. H.</p> <p>1979-01-01</p> <p>The Bununu howardite is a polymict regolith breccia which contains impact <span class="hlt">melt</span> that is largely restricted to a 1-cm thick intrusion containing residual glass. As in Malvern, the <span class="hlt">melt</span> rock contains <span class="hlt">melt</span> with meteoritic Ni-Co contents. The cooling rate, interpreted for forming glass from this composition, is a few tenths of a degree per minute. The intrusive <span class="hlt">melts</span> rock, which is a feature unique to Bununu, may indicate that Bununu was consolidated at the time of impact <span class="hlt">melting</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/5928207"><span id="translatedtitle">Ultra slow EB <span class="hlt">melting</span> to reduce reactor cladding</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Worcester, S.A.; Woods, C.R.; Galer, G.S.; Propst, R.L.</p> <p>1989-03-28</p> <p>A process is described for making an electron beam <span class="hlt">melted</span> fuel element liner material from sponge zirconium, the process comprising: electron beam <span class="hlt">melting</span> sponge zirconium at a <span class="hlt">melting</span> rate of less than 1 inch per hour to form an electron beam <span class="hlt">melted</span> zirconium material containing less than 300 ppm iron, less than 400 ppm oxygen, and less than 5 ppm aluminum; and alloying the electron beam <span class="hlt">melted</span> zirconium in a vacuum arc furnace with 0.1-2.0 weight percent of tin.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1985Metic..20..575D"><span id="translatedtitle">The Bloomington (LL6) chondrite and its shock <span class="hlt">melt</span> glasses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dodd, R.; Olsen, E. J.; Clarke, R. S., Jr.</p> <p>1985-09-01</p> <p>The shock <span class="hlt">melt</span> glasses of the Bloomington LL-group chondrite were examined using electron-beam microscopy and compared with data from studies of other shock <span class="hlt">melt</span> glasses. Petrologic and mineralogic characterizations were also performed of the samples. The metal contents of the meteorite were almost wholly Ni-rich martensite. The glasses resembled shock <span class="hlt">melt</span> glasses in L-group chondrites, and were indicative of isochemical <span class="hlt">melting</span> during one <span class="hlt">melt</span> phase, i.e., a very simple history.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19810053546&hterms=History+relations&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DHistory%2Brelations"><span id="translatedtitle">Martian thermal history, <span class="hlt">core</span> segregation, and tectonics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Davies, G. F.; Arvidson, R. E.</p> <p>1981-01-01</p> <p>A series of calculated thermal histories of Mars is presented, and their possible relation to surface tectonic history is discussed. The models include convective heat transport through an empirical approximation, and heating by radioactivity and <span class="hlt">core</span> segregation. Initial temperature and the timing and duration of <span class="hlt">core</span> segregation are treated as free parameters. The initial temperature is the main determinant of Martian thermal evolution: as it is varied from 20 to 100% of the present mean temperature, the maximum in surface heat flux moves from very recent to very early in Martian history. For the latter cases, the details of <span class="hlt">core</span> segregation control the detailed timing of a peak in the thermal flux that exceeded 100 mW/sq m. It is suggested that the early disruption of cratered terrain crust in the northern hemisphere and subsequent volcanic resurfacing may have been related to <span class="hlt">core</span> segregation. This would be consistent with a scenario in which an early period of <span class="hlt">core</span> segregation generated a marked peak in the thermal flux that may have led to extensive partial <span class="hlt">melting</span> and volcanism. This scenario would require Mars to have had an initial mean temperature comparable to the present value.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/1057665"><span id="translatedtitle">Energy Saving <span class="hlt">Melting</span> and Revert Reduction Technology: <span class="hlt">Melting</span> Efficiency in Die Casting Operations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>David Schwam</p> <p>2012-12-15</p> <p>This project addressed multiple aspects of the aluminum <span class="hlt">melting</span> and handling in die casting operations, with the objective of increasing the energy efficiency while improving the quality of the molten metal. The efficiency of <span class="hlt">melting</span> has always played an important role in the profitability of aluminum die casting operations. Consequently, die casters need to make careful choices in selecting and operating <span class="hlt">melting</span> equipment and procedures. The capital cost of new <span class="hlt">melting</span> equipment with higher efficiency can sometimes be recovered relatively fast when it replaces old <span class="hlt">melting</span> equipment with lower efficiency. Upgrades designed to improve energy efficiency of existing equipment may be well justified. Energy efficiency is however not the only factor in optimizing <span class="hlt">melting</span> operations. <span class="hlt">Melt</span> losses and metal quality are also very important. Selection of <span class="hlt">melting</span> equipment has to take into consideration the specific conditions at the die casting shop such as availability of floor space, average quantity of metal used as well as the ability to supply more metal during peaks in demand. In all these cases, it is essential to make informed decisions based on the best available data.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/22303905"><span id="translatedtitle">Internal stress-induced <span class="hlt">melting</span> below <span class="hlt">melting</span> temperature at high-rate laser heating</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hwang, Yong Seok, E-mail: yshwang@iastate.edu [Department of Aerospace Engineering, Iowa State University, Ames, Iowa 50011 (United States); Levitas, Valery I., E-mail: vlevitas@iastate.edu [Departments of Aerospace Engineering, Mechanical Engineering, and Material Science and Engineering, Iowa State University, Ames, Iowa 50011 (United States)</p> <p>2014-06-30</p> <p>In this Letter, continuum thermodynamic and phase field approaches (PFAs) predicted internal stress-induced reduction in <span class="hlt">melting</span> temperature for laser-irradiated heating of a nanolayer. Internal stresses appear due to thermal strain under constrained conditions and completely relax during <span class="hlt">melting</span>, producing an additional thermodynamic driving force for <span class="hlt">melting</span>. Thermodynamic <span class="hlt">melting</span> temperature for Al reduces from 933.67?K for a stress-free condition down to 898.1?K for uniaxial strain and to 920.8?K for plane strain. Our PFA simulations demonstrated barrierless surface-induced <span class="hlt">melt</span> nucleation below these temperatures and propagation of two solid-<span class="hlt">melt</span> interfaces toward each other at the temperatures very close to the corresponding predicted thermodynamic equilibrium temperatures for the heating rate Q?1.51×10{sup 10}K/s. At higher heating rates, kinetic superheating competes with a reduction in <span class="hlt">melting</span> temperature and <span class="hlt">melting</span> under uniaxial strain occurs at 902.1?K for Q?=?1.51?×?10{sup 11?}K/s and 936.9?K for Q?=?1.46?×?10{sup 12?}K/s.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014ApPhL.104z3106H"><span id="translatedtitle">Internal stress-induced <span class="hlt">melting</span> below <span class="hlt">melting</span> temperature at high-rate laser heating</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hwang, Yong Seok; Levitas, Valery I.</p> <p>2014-06-01</p> <p>In this Letter, continuum thermodynamic and phase field approaches (PFAs) predicted internal stress-induced reduction in <span class="hlt">melting</span> temperature for laser-irradiated heating of a nanolayer. Internal stresses appear due to thermal strain under constrained conditions and completely relax during <span class="hlt">melting</span>, producing an additional thermodynamic driving force for <span class="hlt">melting</span>. Thermodynamic <span class="hlt">melting</span> temperature for Al reduces from 933.67 K for a stress-free condition down to 898.1 K for uniaxial strain and to 920.8 K for plane strain. Our PFA simulations demonstrated barrierless surface-induced <span class="hlt">melt</span> nucleation below these temperatures and propagation of two solid-<span class="hlt">melt</span> interfaces toward each other at the temperatures very close to the corresponding predicted thermodynamic equilibrium temperatures for the heating rate Q ?1.51×1010K/s. At higher heating rates, kinetic superheating competes with a reduction in <span class="hlt">melting</span> temperature and <span class="hlt">melting</span> under uniaxial strain occurs at 902.1 K for Q = 1.51 × 1011 K/s and 936.9 K for Q = 1.46 × 1012 K/s.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2003TrGeo...2..547M"><span id="translatedtitle">Compositional Model for the Earth's <span class="hlt">Core</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McDonough, W. F.</p> <p>2003-12-01</p> <p>The remote setting of the Earth's <span class="hlt">core</span> tests our ability to assess its physical and chemical characteristics. Extending out to half an Earth radii, the metallic <span class="hlt">core</span> constitutes a sixth of the planet's volume and a third of its mass (see Table 1 for physical properties of the Earth's <span class="hlt">core</span>). The boundary between the silicate mantle and the <span class="hlt">core</span> (CMB) is remarkable in that it is a zone of greatest contrast in Earth properties. The density increase across this boundary represents a greater contrast than across the crust-ocean surface. The Earth's gravitational acceleration reaches a maximum (10.7 m s-2) at the CMB and this boundary is also the site of the greatest temperature gradient in the Earth. (The temperature at the base of the mantle (˜2,900 °C) is not well established, and that at the top of the inner <span class="hlt">core</span> is even less securely known (˜3,500-4,500 °C).) The pressure range throughout the <span class="hlt">core</span> (i.e., 136 GPa to >360 GPa) makes recreating environmental conditions in most experimental labs impossible, excepting a few diamond anvil facilities or those with high-powered, shock-<span class="hlt">melting</span> guns (see Chapter 2.14). Thus, our understanding of the <span class="hlt">core</span> is based on very few pieces of direct evidence and many fragments of indirect observations. Direct evidence comes from seismology, geodesy, geo- and paleomagnetism, and, relatively recently isotope geochemistry (see Section 2.15.6). Indirect evidence comes from geochemistry, cosmochemistry, and meteoritics; further constraints on the <span class="hlt">core</span> system are gained from studies in experimental petrology, mineral physics, ab initio calculations, and evaluations of the Earth's energy budget (e.g., geodynamo calculations, <span class="hlt">core</span> crystallization, heat flow across the <span class="hlt">core</span>-mantle boundary). Figure 1 provides a synopsis of research on the Earth's <span class="hlt">core</span>, and the relative relationship between disciplines. Feedback loops between all of these disciplines refine other's understanding of the Earth's <span class="hlt">core</span>. Table 1. Physical properties of the Earth's <span class="hlt">core</span> UnitsRefs. Mass Earth5.9736E+24kg1 Inner <span class="hlt">core</span>9.675E+22kg1 Outer <span class="hlt">core</span>1.835E+24kg1 <span class="hlt">Core</span>1.932E+24kg1 Mantle4.043E+24kg1 Inner <span class="hlt">core</span> to <span class="hlt">core</span> (%)5.0% <span class="hlt">Core</span> to Earth (%)32.3% Depth <span class="hlt">Core</span>-mantle boundary3,483±5km2 Inner-outer <span class="hlt">core</span> boundary1,220±10km2 Mean radius of the Earth6,371.01±0.02km1 Volume relative to planet Inner <span class="hlt">core</span>7.606E+09(0.7%)km3 Inner <span class="hlt">core</span> relative to the bulk <span class="hlt">core</span>4.3% Outer <span class="hlt">core</span>1.694E+11(15.6%)km3 Bulk <span class="hlt">core</span>1.770E+11(16.3%)km3 Silicate earth9.138E+11(84%)km3 Earth1.083E+12km3 Moment of inertia constants Earth mean moment of inertia (I)0.3299765Ma21 Earth mean moment of inertia (I)0.3307144MR021 Mantle: Im/Ma20.29215Ma21 Fluid <span class="hlt">core</span>: If/Ma20.03757Ma21 Inner <span class="hlt">core</span>: Iic/Ma22.35E-4Ma21 <span class="hlt">Core</span>: If+ic/Mf+icaf20.392Ma21 1 - Yoder (1995), 2 - Masters and Shearer (1995). M is the Earth's mass, a is the Earth's equatorial radius, R0 is the radius for an oblate spheroidal Earth, Im is the moment of inertia for the mantle, If is the moment of inertia for the outer (fluid) <span class="hlt">core</span>, Iic is the moment of inertia for the inner <span class="hlt">core</span>, and If+ic/Mf+icaf2 is the mean moment of inertia for the <span class="hlt">core</span>. (11K)Figure 1. The relative relationship between disciplines involved in research on the Earth's <span class="hlt">core</span> and the nature of data and information that come from these various investigations. Studies listed in the upper row yield direct evidence on properties of the <span class="hlt">core</span>. Those in the middle row yield indirect evidence on the composition of the Earth's <span class="hlt">core</span>, whereas findings from disciplines listed on the bottom row provide descriptions of the state conditions for the <span class="hlt">core</span> and its formation.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2003AGUFM.V42E..07M"><span id="translatedtitle">Chemical Order in Silicate <span class="hlt">Melts</span>: Implications for Microscopic Origins of Mantle <span class="hlt">Melting</span> Behavior</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mysen, B. O.; Lee, S.; Cody, G. D.; Fei, Y.</p> <p>2003-12-01</p> <p>Configurational thermodynamic properties of silicate <span class="hlt">melts</span> (e.g. activity coefficient of silica) at high pressure govern composition of <span class="hlt">melts</span> in equilibrium with mantle mineral assemblages. These properties are controlled by the distribution of framework units (e.g. [4]Si, [5,6]Si, [4]Al), and the disorder among network-modifying cations (e.g. Ca2+, Mg2+, Na+) in the <span class="hlt">melts</span> (Lee, Fei, Cody, & Mysen, Geophys. Res. Lett., 2003, 30, 1845; Lee and Stebbins, Geochim. Cosmochim. Acta., 2003, 67, 1699). Spectroscopic data obtained in the diamond anvil cell (DAC) together with quantum chemical simulations, allow us to measure details of distributions of framework units and network modifying cations with varying pressure, temperature and compositions. Here we report structural details of model basaltic <span class="hlt">melts</span> (sodium silicate and aluminosilicates with varying degree of polymerization) mainly using solid state NMR, vibrational spectroscopy and synchrotron X-ray with DAC. These results highlight the tendency for chemical ordering resulted from cation mixing in silicate <span class="hlt">melts</span> and glasses at ambient as well as high pressure (6-10 GPa). The chemical ordering among framework units leads to the formation of [5,6]Si-O-[4]Si in silicates and [5,6]Al-O-[4]Si in aluminosilicates, contributing to the total negative deviation of silica activity from ideal solution in silicate <span class="hlt">melts</span> at high pressure. Network-modifying cations also prefer to form dissimilar pairs (e.g. Ca-Na and Mg-Ba). These results indicate that there will be a further reduction in the activity coefficient of silica in multi-component <span class="hlt">melts</span>. We also present modeling results of configurational enthalpy and entropy of multi-component silicate <span class="hlt">melts</span> derived from the spectroscopic analysis and calculated the effect of degree of chemical order in <span class="hlt">melt</span> properties. Increasing chemical ordering among framework units leads to a decrease in configurational entropy and enthalpy of <span class="hlt">melts</span>, and also contributes to the decrease of silica activity coefficient in <span class="hlt">melts</span>. Structural ordering in the <span class="hlt">melts</span>, together with extensive mixing among framework units, strongly affect the composition of the partial <span class="hlt">melts</span>. The alkali or silica content in equilibrium with mantle peridotite can increase as a results of these structural effects, thus manifesting the strong links between <span class="hlt">melt</span> structures, properties and magmatic processes.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/18432243"><span id="translatedtitle">Hydrous silicate <span class="hlt">melt</span> at high pressure.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mookherjee, Mainak; Stixrude, Lars; Karki, Bijaya</p> <p>2008-04-24</p> <p>The structure and physical properties of hydrous silicate <span class="hlt">melts</span> and the solubility of water in <span class="hlt">melts</span> over most of the pressure regime of Earth's mantle (up to 136 GPa) remain unknown. At low pressure (up to a few gigapascals) the solubility of water increases rapidly with increasing pressure, and water has a large influence on the solidus temperature, density, viscosity and electrical conductivity. Here we report the results of first-principles molecular dynamics simulations of hydrous MgSiO3 <span class="hlt">melt</span>. These show that pressure has a profound influence on speciation of the water component, which changes from being dominated by hydroxyls and water molecules at low pressure to extended structures at high pressure. We link this change in structure to our finding that the water-silicate system becomes increasingly ideal at high pressure: we find complete miscibility of water and silicate <span class="hlt">melt</span> throughout almost the entire mantle pressure regime. On the basis of our results, we argue that a buoyantly stable <span class="hlt">melt</span> at the base of the upper mantle would contain approximately 3 wt% water and have an electrical conductivity of 18 S m(-1), and should therefore be detectable by means of electromagnetic sounding. PMID:18432243</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/39661013"><span id="translatedtitle">Low <span class="hlt">melt</span> fraction connectivity of granitic and tonalitic <span class="hlt">melts</span> in a mafic crustal rock at 800?°C and 1 GPa</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Afina Lupulescu; E. Bruce Watson</p> <p>1999-01-01</p> <p>In the absence of an externally applied stress, the segregation of small amounts of granitic or tonalitic <span class="hlt">melts</span> from their\\u000a residual mafic crystals is possible only if the <span class="hlt">melt</span> forms an interconnected network phase. Accordingly, this research focuses\\u000a on <span class="hlt">melt</span> connectivity at low <span class="hlt">melt</span> fraction (<4 wt% or 5 vol.%). Connectivity of granitic and tonalitic <span class="hlt">melts</span> in amphibole-rich\\u000a rock was</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6978113"><span id="translatedtitle">Analysis of production reactor response during a <span class="hlt">postulated</span> Loss-of-River Water event using CONTAIN/SR</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>O'Kula, K.R.; Wooten, L.A. (Westinghouse Savannah River Co., Aiken, SC (United States)); Jenkins, T.B. (Concord Associates, Inc., Knoxville, TN (United States))</p> <p>1992-06-01</p> <p>This report discusses the CONTAIN/SR computer code, developed at the Savannah River Technology Center and Sandia National Laboratories for Probabilistic Safety Assessment (PSA) applications, which is used to analyze K Reactor plant conditions following a design basis earthquake to assist post-accident recovery planning. The <span class="hlt">postulated</span> event, a Loss-of-River Water (LORW) accident, requires analysis of the K Reactor confinement system assuming seismic event-caused loss of forced air flow through Radiologically Controlled (RCAs) and other building areas, including adjoining personnel and auxiliary equipment zones. The CONTAIN/SR code calculations predict the expected environment in the K Reactor building with a seismically-qualified flow path for natural circulation, under design basis conditions specifying a 50 gal/min leak of tritiated heavy water. Despite loss of active fan flow, preferential air flow patterns are calculated to flow from clean'' areas towards the RCAs. Ventilation characteristics of the building reduce tritiated water vapor concentrations to habitable levels, assuming plastic suits and clean breathing air supplies are available. Unprotected dose rates to recovery workers in the heat exchanger zone of the building will range from 120 mrem/hour to 780 mrem/hour, depending on evaporation conditions near spilled heavy-water pools. It is concluded habitability issues for recovery are not driven by temperature concerns in reactor building zones. However, the results indicate radiological suits with cool air supplies will assure adequate conditions for operators and recovery teams, and mitigate tritium uptake hazards from splashing or other direct contact mechanisms.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/10191550"><span id="translatedtitle">Analysis of production reactor response during a <span class="hlt">postulated</span> Loss-of-River Water event using CONTAIN/SR</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>O`Kula, K.R.; Wooten, L.A. [Westinghouse Savannah River Co., Aiken, SC (United States); Jenkins, T.B. [Concord Associates, Inc., Knoxville, TN (United States)</p> <p>1992-06-01</p> <p>This report discusses the CONTAIN/SR computer code, developed at the Savannah River Technology Center and Sandia National Laboratories for Probabilistic Safety Assessment (PSA) applications, which is used to analyze K Reactor plant conditions following a design basis earthquake to assist post-accident recovery planning. The <span class="hlt">postulated</span> event, a Loss-of-River Water (LORW) accident, requires analysis of the K Reactor confinement system assuming seismic event-caused loss of forced air flow through Radiologically Controlled (RCAs) and other building areas, including adjoining personnel and auxiliary equipment zones. The CONTAIN/SR code calculations predict the expected environment in the K Reactor building with a seismically-qualified flow path for natural circulation, under design basis conditions specifying a 50 gal/min leak of tritiated heavy water. Despite loss of active fan flow, preferential air flow patterns are calculated to flow from ``clean`` areas towards the RCAs. Ventilation characteristics of the building reduce tritiated water vapor concentrations to habitable levels, assuming plastic suits and clean breathing air supplies are available. Unprotected dose rates to recovery workers in the heat exchanger zone of the building will range from 120 mrem/hour to 780 mrem/hour, depending on evaporation conditions near spilled heavy-water pools. It is concluded habitability issues for recovery are not driven by temperature concerns in reactor building zones. However, the results indicate radiological suits with cool air supplies will assure adequate conditions for operators and recovery teams, and mitigate tritium uptake hazards from splashing or other direct contact mechanisms.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1995AcASn..36..229W"><span id="translatedtitle">Generalization of the principle of light speed invariance. (II). On the <span class="hlt">postulate</span> of the constancy of light speed in curved space-time.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Renchuan</p> <p>1995-09-01</p> <p>On account of the equivalence principle and consistence of theories, the author generalized the <span class="hlt">postulate</span> of the constancy of light speed to the curved space-time and investigated the coordinate problems in general relativity. From physical viewpoint the author illuminates the significance of coordinates, coordinate transformations and description and measurement of physical quantities.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/6280967"><span id="translatedtitle">Review of experiments to evaluate the ability of electrical heater rods to simulate nuclear fuel rod behavior during <span class="hlt">postulated</span> loss-of-coolant accidents in light water reactors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>McPherson, G D; Tolman, E L</p> <p>1980-01-01</p> <p>Issues related to using electrical fuel rod simulators to simulate nuclear fuel rod behavior during <span class="hlt">postulated</span> loss-of-coolant accident (LOCA) conditions in light water reactors are summarized. Experimental programs which will provide a data base for comparing electrical heater rod and nuclear fuel rod LOCA responses are reviewed.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/61376388"><span id="translatedtitle">Technology, safety and costs of decommissioning reference nuclear fuel cycle and non-fuel cycle facilities following <span class="hlt">postulated</span> accidents. Main report. Volume 1</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Elder</p> <p>1985-01-01</p> <p>Technical requirements, costs and safety are conceptually evaluated for the post-accident cleanup and decommissioning of fuel cycle and non-fuel cycle facilities that have experienced a significant accident. Accident cleanup is <span class="hlt">postulated</span> to include (1) initial decontamination of building surfaces to reduce the subsequent occupational dose to cleanup and decommissioning workers and (2) management of the resulting wastes. Decommissioning is assumed</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60713036"><span id="translatedtitle">Supplementary documentation for an Environmental Impact Statement regarding the Pantex Plant: radiological consequences of immediate inhalation of plutonium dispersed by <span class="hlt">postulated</span> accidents</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>J. C. Elder; R. H. Olsher; J. M. Graf</p> <p>1982-01-01</p> <p>This report documents work performed in support of preparation of an Environmental Impact Statement (EIS) regarding the Department of Energy's (DOE) Pantex Plant near Amarillo, Texas. It describes methods used to estimate potential health consequences offsite resulting from inhalation of plutonium dispersed by each of several <span class="hlt">postulated</span> accidents. The primary topic of this report is the delayed health effects of</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2000GeCoA..64.3887J"><span id="translatedtitle">Metal-silicate partitioning of Co, Ga, and W: dependence on silicate <span class="hlt">melt</span> composition</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jaeger, Windy L.; Drake, Michael J.</p> <p>2000-11-01</p> <p>This study investigates the effect of silicate <span class="hlt">melt</span> composition on metal/silicate partitioning for Co 2+, Ga 3+, and W 4+ at 1300°C, 1 atm, and a log fO 2 of -12. Five glasses in the system MgO-CaO-Al 2O 3-TiO 2-SiO 2 with nbo/t (nonbridging oxygens/tetrahedrally coordinated cations) values ranging from 0.25 to 1.52 were used as starting materials. For W and Co experiments the five glasses were equilibrated with W or Co wire loops, respectively, at the specified run conditions. For Ga experiments the glasses were doped with 2 wt.% Ga 2O 3 and equilibrated with pure Fe. All phases were analyzed by an electron microprobe. The metal/silicate partition coefficient for W depends strongly on <span class="hlt">melt</span> basicity, whereas the effect of <span class="hlt">melt</span> composition on Ga partitioning is less pronounced and for Co it is negligible. DW decreases rapidly with increasing nbo/t, DGa decreases moderately with increasing degree of <span class="hlt">melt</span> basicity, and DCo remains relatively constant over our compositional range. The findings of this study indicate that the effect of <span class="hlt">melt</span> composition on trace element solubility is a function of cation oxidation state such that high valency cations like W 4+ are more readily dissolved in depolymerized <span class="hlt">melts</span> which have a higher ratio of nonbridging oxygens, and lower valency cations like Co 2+ are relatively independent of the parameter nbo/t. These results confirm that the composition of the primitive mantle is an important factor in constraining how siderophile trace elements distribute themselves between an Fe-metal <span class="hlt">core</span> and the bulk silicate Earth during an early magma ocean differentiation event.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFMMR41B4406S"><span id="translatedtitle">Properties of Silicate <span class="hlt">Melts</span> at High Pressure and Temperature from Ab Initio Calculations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Seclaman, A. C.; Caracas, R.</p> <p>2014-12-01</p> <p>The evolution of planetary interiors is intrinsically connected to the behavior and properties of silicate <span class="hlt">melts</span> at high pressures and temperatures. Our work comes as a complement to existing data expanding the pressure, temperature, and compositional ranges. We used the V.A.S.P. code to perform NVT Molecular Dynamics simulations on two basic compositions: Mg2SiO4 and MgSiO3. All calculations are done within augmented planar wave formalism of the Density Functional Theory. Supercells of 160 atoms clino-enstatite and 112 atoms forsterite were <span class="hlt">melted</span> at 5000K and then cooled and thermalized, using the Nose-Hoover thermostat, at temperatures more representative of Earth's interior (3000 and 4000K). The pressure range of our investigations spans from 0 to approximately 160GPa. Since important properties, density and magnetism, are dependent on the presence of iron we also created (Fex-1,Mgx)SiO3 and (Fex-1,Mgx)2SiO4<span class="hlt">melts</span> from the thermalized pure compositions by replacing the desired amount of magnesium atoms with iron. Because other transitional elements present similar behavior as iron, and nickel is an important element in the <span class="hlt">core</span>, compositions containing different amounts of nickel were also created by adding extra Ni atoms in the system. We analyze in detail the behavior with pressure of the density, clustering and coordination, total magnetization, and thermodynamical parameters of the <span class="hlt">melts</span>. Our results indicate that changes in the structure and magnetic moment of the Forsterite <span class="hlt">melt</span> begin at relatively low pressure. As an application of our data to the Earth's present deep interior we analyzed in great detail various possible mixtures of Fe bearing <span class="hlt">melt</span> and solid mantle in an attempt to fit the density estimated for the Ultra Low Velocity Zones.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2006HMT....42..464Z"><span id="translatedtitle">Diffusion-controlled <span class="hlt">melting</span> and re-solidification of metal micro layers on a reactive substrate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Hui; Sekulic, Dusan P.</p> <p>2006-04-01</p> <p>The paper offers a theoretical approach to a prediction of residue formation inherent to <span class="hlt">melting</span> and subsequent solidification of micro layers of molten aluminum alloys. The residue formation follows a reactive flow of a portion of the <span class="hlt">melt</span> that is removed by a surface tension action. The residue portion solidifies in situ. The phenomenon studied is associated with materials’ processing during controlled atmosphere brazing of aluminum. The model assumes that diffusion of Silicon, present in an Al+Si clad of a brazing sheet, has a twofold role. First, a solid state Si diffusion prior to <span class="hlt">melting</span> and across the clad-<span class="hlt">core</span> interface of a composite brazing sheet takes place and modifies alloys’ composition on both sides of the interface. Subsequently, Si diffusion within clad controls the <span class="hlt">melting</span> process. Both processes are essential for clad residue formation. The approach advocated in this paper leads to a prediction of the residue formation through a modeling of the non-equilibrium diffusion-controlled <span class="hlt">melting</span>. A heuristic interpretation of physical mechanisms was discussed and a related mathematical model devised. The model was solved numerically in terms of Si concentration distributions for a moving boundary problem and corroborated with empirical data. Empirical data were gathered using an experimental controlled atmosphere brazing facility. The results of the modeling and their corroboration with the experimental data indicate a strong dependence of residue formations on the pre-<span class="hlt">melting</span> state of the clad, in particular on the grain size within Al-clad matrix. A good agreement between numerically predicted residue mass and experimental findings is documented in detail.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2004AGUFM.T51C0460R"><span id="translatedtitle">Rheological Consequences of Incipient <span class="hlt">Melting</span> in Crustal Rocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rosenberg, C. L.</p> <p>2004-12-01</p> <p>A review and reinterpretation of older experimental data on the deformation of partially-<span class="hlt">melted</span> granite reveals a non-linear strength decrease with increasing <span class="hlt">melt</span> fractions. This decrease is characterised by two sharp discontinuities, each reflecting a dramatic change of strength within a limited range of <span class="hlt">melt</span> fractions. A first discontinuity is shown by all experiments at <span class="hlt">melt</span> fractions of approximately 0.07. The strength drop at <span class="hlt">melt</span> fractions smaller than this discontinuity is the largest over the entire <span class="hlt">melting</span> range. Hence the greatest weakening occurs well below the well known rheologically critical <span class="hlt">melt</span> percentage (RCMP). In contrast to previous interpretations, the RCMP is inferred to occur, at <span class="hlt">melt</span> fractions of 0.4 to 0.6, for crystallising as well as for <span class="hlt">melting</span> rocks. However, the magnitude of the stress drop at the RCMP is negligible compared to the stress drop at <span class="hlt">melt</span> fractions < 0.07. Increasing <span class="hlt">melt</span> content in the range of <span class="hlt">melt</span> fractions between 0.0 and 0.07 induces a rapid increase in the percentage of <span class="hlt">melt</span>-bearing grain boundaries. This increase is not linear and barely existent at <span class="hlt">melt</span> fractions greater than 0.1. Therefore, the increasing proportion of wetted grain boundaries is suggested to be the primary cause for the dramatic strength drop described above. Extrapolation of the existing deformational experiments on partially-<span class="hlt">melted</span> crustal rocks to natural conditions remains speculative due to the lack of experiments performed at controlled <span class="hlt">melt</span> pressure, under conditions favouring steady state, in the dislocation or diffusion creep regime. However, the existing data suggest that the attainment of a <span class="hlt">melt</span> fraction < 0.07 will control the large-scale localisation of deformation into partially-<span class="hlt">melted</span> crustal layers, irrespective of the attainment of the RCMP. Hence, very small amounts of <span class="hlt">melt</span>, eventually too small to be imaged by geophysical methods, may exert a drastic control on large-scale localization of deformation.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013GeCoA.102..191D"><span id="translatedtitle">Carbon solution and partitioning between metallic and silicate <span class="hlt">melts</span> in a shallow magma ocean: Implications for the origin and distribution of terrestrial carbon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dasgupta, Rajdeep; Chi, Han; Shimizu, Nobumichi; Buono, Antonio S.; Walker, David</p> <p>2013-02-01</p> <p>The origin of bulk silicate Earth carbon inventory is unknown and the fate of carbon during the early Earth differentiation and <span class="hlt">core</span> formation is a missing link in the evolution of the terrestrial carbon cycle. Here we present high pressure (P)-temperature (T) experiments that offer new constraints upon the partitioning of carbon between metallic and silicate <span class="hlt">melt</span> in a shallow magma ocean. Experiments were performed at 1-5 GPa, 1600-2100 °C on mixtures of synthetic or natural silicates (tholeiitic basalt/alkali basalt/komatiite/fertile peridotite) and Fe-Ni-C ± Co ± S contained in graphite or MgO capsules. All the experiments produced immiscible Fe-rich metallic and silicate <span class="hlt">melts</span> at oxygen fugacity (fO2) between ˜IW-1.5 and IW-1.9. Carbon and hydrogen concentrations of basaltic glasses and non-glassy quenched silicate <span class="hlt">melts</span> were determined using secondary ionization mass spectrometry (SIMS) and speciation of dissolved C-O-H volatiles in silicate glasses was studied using Raman spectroscopy. Carbon contents of metallic <span class="hlt">melts</span> were determined using both electron microprobe and SIMS. Our experiments indicate that at <span class="hlt">core</span>-forming, reduced conditions, carbon in deep mafic-ultramafic magmas may dissolve primarily as various hydrogenated species but the total carbon storage capacity, although is significantly higher than solubility of CO2 under similar conditions, remains low (<500 ppm). The total carbon content in our reduced <span class="hlt">melts</span> at graphite saturation increases with increasing <span class="hlt">melt</span> depolymerization (NBO/T), consistent with recent spectroscopic studies, and modestly with increasing hydration. Carbon behaves as a metal-loving element during <span class="hlt">core</span>-mantle separation and our experimental DCmetal/silicate varies between ˜4750 and ?150 and increases with increasing pressure and decreases with increasing temperature and <span class="hlt">melt</span> NBO/T. Our data suggest that if only a trace amount of carbon (˜730 ppm C) was available during early Earth differentiation, most of it was partitioned to the <span class="hlt">core</span> (with 0.20-0.25 wt.% C) and no more than ˜10-30% of the present-day mantle carbon budget (50-200 ppm CO2) could be derived from a magma ocean residual to <span class="hlt">core</span> formation. With equilibrium <span class="hlt">core</span> formation removing most of the carbon initially retained in the terrestrial magma ocean, explanation of the modern bulk silicate Earth carbon inventory requires a later replenishment mechanism. Partial entrapment of metal <span class="hlt">melt</span> in solid silicate matrix, carbon ingassing by magma ocean-atmosphere interaction, and carbon outgassing from the <span class="hlt">core</span> aided by reaction of <span class="hlt">core</span> metal and deeply subducted water are some of the viable mechanisms.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=USGSPUBS&redirectUrl=http://pubs.er.usgs.gov/publication/70010165"><span id="translatedtitle"><span class="hlt">Melting</span> relations in the Fe-rich portion of the system FeFeS at 30 kb pressure</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Brett, R.; Bell, P.M.</p> <p>1969-01-01</p> <p>The <span class="hlt">melting</span> relations of FeFeS mixtures covering the composition range from Fe to Fe67S33 have been determined at 30 kb pressure. The phase relations are similar to those at low pressure. The eutectic has a composition of Fe72.9S27.1 and a temperature of 990??C. Solubility of S in Fe at elevated temperatures at 30 kb is of the same order of magnitude as at low pressure. Sulfur may have significantly lowered the <span class="hlt">melting</span> point of iron in the upper mantle during the period of coalescence of metal prior to <span class="hlt">core</span> formation in the primitive earth. ?? 1969.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20130011096&hterms=Sutton&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSutton"><span id="translatedtitle">Compositions of Magmatic and Impact <span class="hlt">Melt</span> Sulfides in Tissint And EETA79001: Precursors of Immiscible Sulfide <span class="hlt">Melt</span> Blebs in Shergottite Impact <span class="hlt">Melts</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ross, D. K.; Rao, M. N.; Nyquist, L.; Agee, C.; Sutton, S.</p> <p>2013-01-01</p> <p>Immiscible sulfide <span class="hlt">melt</span> spherules are locally very abundant in shergottite impact <span class="hlt">melts</span>. These <span class="hlt">melts</span> can also contain samples of Martian atmospheric gases [1], and cosmogenic nuclides [2] that are present in impact <span class="hlt">melt</span>, but not in the host shergottite, indicating some components in the <span class="hlt">melt</span> resided at the Martian surface. These observations show that some regolith components are, at least locally, present in the impact <span class="hlt">melts</span>. This view also suggests that one source of the over-abundant sulfur in these impact <span class="hlt">melts</span> could be sulfates that are major constituents of Martian regolith, and that the sulfates were reduced during shock heating to sulfide. An alternative view is that sulfide spherules in impact <span class="hlt">melts</span> are produced solely by <span class="hlt">melting</span> the crystalline sulfide minerals (dominantly pyrrhotite, Fe(1-x)S) that are present in shergottites [3]. In this abstract we report new analyses of the compositions of sulfide immiscible <span class="hlt">melt</span> spherules and pyrrhotite in the shergottites Tissint, and EETA79001,507, and we use these data to investigate the possible origins of the immiscible sulfide <span class="hlt">melt</span> spherules. In particular, we use the metal/S ratios determined in these blebs as potential diagnostic criteria for tracking the source material from which the numerous sulfide blebs were generated by shock in these <span class="hlt">melts</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19940011833&hterms=explosives&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dexplosives"><span id="translatedtitle">Explosive volcanism and the compositions of the <span class="hlt">cores</span> of differentiated asteroids</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keil, Klaus; Wilson, Lionel</p> <p>1993-01-01</p> <p>Eleven iron meteorite groups showing correlations between Ni and siderophile trace elements that are predictable by distribution coefficients between liquid and solid metal of fractionally crystallizing metal magmas, are interpreted to be fragments of the fractionally crystallized <span class="hlt">cores</span> of 11 differentiated asteroids. Many of these groups crystallized from S-depleted magmas which we propose resulted from removal of the first partial <span class="hlt">melt</span> (a Fe,Ni-FeS cotectic) by explosive pyroclastic volcanism. It is shown that these dense, negatively buoyant <span class="hlt">melts</span> can be driven to asteroidal surfaces by the combination of an excess pressure in the <span class="hlt">melt</span> and the presence of buoyant bubbles of gas which decrease the bulk density of the <span class="hlt">melt</span>. It is also shown that in typical asteroidal materials, veins will form which grow into dikes and serve as pathways for migration of <span class="hlt">melt</span> and gas to asteroidal surfaces. Since cotectic Fe,Ni-FeS <span class="hlt">melt</span> consists of about 85 wt. percent FeS and 15 wt. percent Fe,Ni, removal of small volumes of eutectic <span class="hlt">melts</span> results in major loss of S but only minor loss of Fe,Ni, thus leaving sufficient Fe,Ni to form sizeable asteroidal <span class="hlt">cores</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/10123631"><span id="translatedtitle">Scrap uranium recycling via electron beam <span class="hlt">melting</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>McKoon, R.</p> <p>1993-11-01</p> <p>A program is underway at the Lawrence Livermore National Laboratory (LLNL) to recycle scrap uranium metal. Currently, much of the material from forging and machining processes is considered radioactive waste and is disposed of by oxidation and encapsulation at significant cost. In the recycling process, uranium and uranium alloys in various forms will be processed by electron beam <span class="hlt">melting</span> and continuously cast into ingots meeting applicable specifications for virgin material. Existing vacuum processing facilities at LLNL are in compliance with all current federal and state environmental, safety and health regulations for the electron beam <span class="hlt">melting</span> and vaporization of uranium metal. One of these facilities has been retrofitted with an auxiliary electron beam gun system, water-cooled hearth, crucible and ingot puller to create an electron beam <span class="hlt">melt</span> furnace. In this furnace, basic process R&D on uranium recycling will be performed with the goal of eventual transfer of this technology to a production facility.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1504.03082.pdf"><span id="translatedtitle">A model for <span class="hlt">melting</span> of confined DNA</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Werner, E; Ambjörnsson, T; Mehlig, B</p> <p>2015-01-01</p> <p>When DNA molecules are heated they denature. This occurs locally so that loops of molten single DNA strands form, connected by intact double-stranded DNA pieces. The properties of this "<span class="hlt">melting</span>" transition have been intensively investigated. Recently there has been a surge of interest in this question, caused by experiments determining the properties of partially bound DNA confined to nanochannels. But how does such confinement affect the <span class="hlt">melting</span> transition? To answer this question we introduce, and solve a model predicting how confinement affects the <span class="hlt">melting</span> transition for a simple model system by first disregarding the effect of self-avoidance. We find that the transition is smoother for narrower channels. By means of Monte-Carlo simulations we then show that a model incorporating self-avoidance shows qualitatively the same behaviour and that the effect of confinement is stronger than in the ideal case.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015PhRvE..91f0702W"><span id="translatedtitle">Model for <span class="hlt">melting</span> of confined DNA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Werner, E.; Reiter-Schad, M.; Ambjörnsson, T.; Mehlig, B.</p> <p>2015-06-01</p> <p>When DNA molecules are heated they denature. This occurs locally so that loops of molten single DNA strands form, connected by intact double-stranded DNA pieces. The properties of this "<span class="hlt">melting</span>" transition have been intensively investigated. Recently there has been a surge of interest in this question, in part caused by experiments determining the properties of partially bound DNA confined to nanochannels. But how does such confinement affect the <span class="hlt">melting</span> transition? To answer this question we introduce and solve a model predicting how confinement affects the <span class="hlt">melting</span> transition for a simple model system by first disregarding the effect of self-avoidance. We find that the transition is smoother for narrower channels. By means of Monte Carlo simulations we then show that a model incorporating self-avoidance shows qualitatively the same behavior and that the effect of confinement is stronger than in the ideal case.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/5632250"><span id="translatedtitle">Zircon refractories for glass-<span class="hlt">melting</span> (review)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mel'nikova, I.G.; Nesterova, T.A.; Razdol'skaya, I.V.</p> <p>1986-03-01</p> <p>The compositions, some of the properties, and the field of application of zircon refractories produced for glass <span class="hlt">melting</span> in the USSR and abroad are presented. The studies show that the zircon refractories of enhanced purity with a total concentration of coloring impurities of 0.3% are of particular interest in the <span class="hlt">melting</span> of several grades of special glasses. Data on the glass resitance of zircon refractories to a series of special glasses are presented; the data were obtained using a dynamic method in a comparison with fused quartz. The degree of corrosion was evaluated from the change in the monitored volume of the specimens before and after contact with the glass. It is clear that the corrosion of the zircon refractories both pressed and also obtained by slip casting is significantly less than the corrosion of refractories made from fused quartz. The zircon refractories can reasonably be used for <span class="hlt">melting</span> a series of glasses with a low concentration of alkalis.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2001JAP....90.3325R"><span id="translatedtitle"><span class="hlt">Melting</span> point of MgO</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ronchi, Claudio; Sheindlin, Mikhail</p> <p>2001-10-01</p> <p>Despite large commercial production of MgO-based ceramics for a wide gamut of applications, the <span class="hlt">melting</span> point of magnesia remained uncertain for almost one century. This article shows that a number of problems must be solved to attain experimental conditions where the solid-liquid phase transition of magnesia can be unambiguously detected, and the temperature be measured with sufficient accuracy. The method adopted in the reported work is based on controlled laser pulse heating. The solidification point was measured by the thermal arrest occurring during cooldown from the <span class="hlt">melt</span>. The measurement of temperature, a most delicate problem for pyrometry applications in semitransparent materials, was obtained by using combined brightness and spectral pyrometers. The experimental and analytical methods are described in some detail. The resulting <span class="hlt">melting</span> point of MgO is 3250±20 K, which is approximately 150 K higher than the value currently recommended.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19910057712&hterms=moon+formed&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmoon%2Bformed"><span id="translatedtitle">Lunar anorthosites, their equilibrium <span class="hlt">melts</span> and the bulk moon</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Phinney, W. C.</p> <p>1991-01-01</p> <p>The present study uses plagioclase compositions and partition coefficients for several elements to estimate <span class="hlt">melts</span> from which lunar anorthosites formed and the partition liquids from which these <span class="hlt">melts</span> were derived. The Fe and Mg contents of the plagioclases are examined for their potential use as predictors of Fe and Mg in associated <span class="hlt">melts</span>. Usable trace elements are employed with selected partition coefficients to predict the equilibrium <span class="hlt">melts</span> for lunar anorthosites, and <span class="hlt">melts</span> for anorthosites are used in various models to calculate the composition of the initial <span class="hlt">melt</span> from which the lunar mantle and eventually the anorthosites evolved. The initial <span class="hlt">melts</span> are compared with bulk moon compositions to evaluate the nature of the <span class="hlt">melting</span> that could have produced the anorthosites. All the models indicate that extensive <span class="hlt">melting</span> of all or nearly all of the lunar mantle is required to produce a lunar crust that constitutes 13-15 percent of the moon's volume.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015EGUGA..17.2815C"><span id="translatedtitle">Seismic Structure of Inner <span class="hlt">Core</span> Boundary Region Correlated with Predicted Outer <span class="hlt">Core</span> Flow</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cormier, Vernon</p> <p>2015-04-01</p> <p>Seismic observations of the inner <span class="hlt">core</span> reveal a pattern of lateral variation in elastic velocities, attenuation, scattering, and anisotropy having a strong but incompletely understood correlation with outer <span class="hlt">core</span> flow predicted from dynamo simulations controlled by heat flow across the <span class="hlt">core</span>-mantle boundary. Currently resolvable large spatial scales exhibit at least a tripartite latitudinal rather than hemispherical pattern in attenuation, elastic velocities, and anisotropy1. These large and smaller scale lateral variations are most densely sampled by seismic body waves traversing the equatorial region of the inner <span class="hlt">core</span>, where cyclonic cylinders of outer <span class="hlt">core</span> convection are tangent to its boundary. Correlations of inner <span class="hlt">core</span> structure with predicted outer <span class="hlt">core</span> flow include (a) a thin (10-40 km thick) zone of low P velocity and possibly near zero S velocity beneath the equatorial eastern Indian Ocean2, which is coincident with a predicted region of strong down-welling flow and inner <span class="hlt">core</span> growth3; (b) a broad region beneath the central and eastern equatorial Pacific that more strongly attenuates PKIKP1, containing small-scale (1-10km) volumetric heterogeneities inferred from the coda of reflected PKiKP waves4, which is coincident with a predicted region of inner <span class="hlt">core</span> <span class="hlt">melting</span>5; and (c) a narrow region of fast P velocity 150 km beneath the eastern equatorial Atlantic6, which is coincident with a predicted secondary, weaker, longitudinal zone of down-welling5. To explain observed decadal time variations on the order of 0.1's of sec for the travel times of PKIKP, the mantle control suggested by these correlations requires either an small upper bound (</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2009AGUFMMR43B1878C"><span id="translatedtitle">Sulfur Contents of Planetary and Protoplanetary <span class="hlt">Cores</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Campbell, A. J.</p> <p>2009-12-01</p> <p>Sulfur is an important component of protoplanetary <span class="hlt">cores</span>, as indicated by the presence of sulfides in iron meteorites, as well as the trace element distributions within iron groups that indicate a fractional crystallization process between metal and coexisting sulfide <span class="hlt">melt</span>. However, sulfur in the Earth’s <span class="hlt">core</span> is expected to be limited to 2 percent or lower, as indicated by the volatility trend of elements in the bulk Earth (Dreibus and Palme, 1996; McDonough, 2003). This follows an assumption that the order of element volatilities determined in condensation calculations for the solar nebula is also appropriate to the devolatilization of planetary bodies such as the Earth, although planets may have devolatilized by non-nebular processes. The assumption can be evaluated by applying the same logic to the iron meteorites as has been applied to the Earth; the irons exhibit volatility depletions among trace siderophile elements that are similar or greater than the volatile depletions in Earth. Estimates of S content in parent metallic <span class="hlt">melts</span> have been reported for the IIAB, IID, IIIAB, IVA, and IVB iron meteorite groups (e.g., Chabot, 2004; Wasson and Huber, 2006). Although there are discrepancies between some models, in most cases one finds that the cosmochemical estimates of S abundance in these protoplanetary <span class="hlt">cores</span> are significantly higher than would be expected on the basis of their volatility trends. For example, CI-normalized S/Ge ratios exceed 100 in some cases. Unless the crystallization models applied to the iron meteorite groups are inaccurate, the assumptions behind the construction of the volatility trends appear to be violated for S in protoplanets (and by extension larger planets, including Earth). Hence, it remains plausible on cosmochemical grounds that Earth’s <span class="hlt">core</span> is S-rich. Gas speciation and partial pressures in the impact plumes produced during planet formation are very different than those in the low-density, hydrogen-rich solar nebula, and should generate a different volatilization-condensation sequence.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/175898"><span id="translatedtitle">Plasma <span class="hlt">melting</span> tests of ceramic filter</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yasui, Shinji; Amakawa, Tadashi; Adachi, Kazuo [Central Research Inst. of Electric Power Industry, Yokosuka, Kanagawa (Japan)</p> <p>1995-12-31</p> <p>Ceramic filter (C/F) elements are one item of the low-level miscellaneous solid wastes with high <span class="hlt">melting</span> temperature generated from nuclear power plants. <span class="hlt">Melting</span> tests of the non-radioactive samples of C/F elements were conducted by using thermal plasma. The present paper discusses the effects of the internal oxygen concentration of the plasma furnace on the decomposed properties of silicon carbide (SiC) mainly contained in the C/F elements, and the possibility of letting the treated waste form contain the volatilized nuclide (Cesium(Cs)) by adding C/F elements to simulated wastes.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/5963147"><span id="translatedtitle"><span class="hlt">Melting</span> of metals above 100 GPa</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Shaner, J.W.; Brown, J.M.; McQueen, R.G.</p> <p>1983-01-01</p> <p>The optical analyzer technique has been used to determine the pressure at which shock compressed iron, tantalum and aluminum can no longer support a longitudinal elastic wave. At this pressure the release wave velocity drops to a value consistent with a calculated bulk sound velocity, indicating partial <span class="hlt">melting</span>. At higher shock pressures, the bulk sound velocities follows a constant rho ..gamma.. model, where ..gamma.. is the Grueneisen parameter. With these measurements we have identified <span class="hlt">melting</span> on the Hugoniot, and we have calibrated three metals as drivers for similar experiments on other materials.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://serc.carleton.edu/NAGTWorkshops/geochemistry/activities/9205.html"><span id="translatedtitle">REE Modeling of <span class="hlt">Melting</span> and Crystallization</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p>Mark Schmitz</p> <p></p> <p>In this activity, students are led through some introductory lecture material on rare earth elements, distribution coefficients, and the derivation of equations relating element concentrations in solids and liquids during processes of both equilibrium and fractional <span class="hlt">melting</span> and crystallization. This lecture material is interspersed with class discussion questions that seek to actively query the students' stepwise understanding of concepts. The activity culminates in the students' construction of rare earth element diagrams for rock samples, a fractional crystallization numerical model (e.g. a spreadsheet) for forward modeling and comparison to data, and an equilibrium modal <span class="hlt">melting</span> model, again for comparison to a real data set.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PMC&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4257017"><span id="translatedtitle">Scleral <span class="hlt">melt</span> following Retisert intravitreal fluocinolone implant</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Georgalas, Ilias; Koutsandrea, Chrysanthi; Papaconstantinou, Dimitrios; Mpouritis, Dimitrios; Petrou, Petros</p> <p>2014-01-01</p> <p>Intravitreal fluocinolone acetonide implant (Retisert) has a high potency, a low solubility, and a very short duration of action in the systemic circulation, enabling the steroid pellet to be small and reducing the risk of systemic side effects. Scleral <span class="hlt">melt</span> has not been reported as a possible complication of Retisert implant. The authors describe the occurrence of scleral <span class="hlt">melt</span> 18 months after the implantation of fluocinolone acetonide implant in a 42-year-old Caucasian woman. To the authors’ knowledge, this is the first report of this possible complication. PMID:25489235</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/871454"><span id="translatedtitle">Rock <span class="hlt">melting</span> tool with annealer section</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bussod, Gilles Y. (Santa Fe, NM); Dick, Aaron J. (Oakland, CA); Cort, George E. (Montrose, CO)</p> <p>1998-01-01</p> <p>A rock <span class="hlt">melting</span> penetrator is provided with an afterbody that rapidly cools a molten geological structure formed around the <span class="hlt">melting</span> tip of the penetrator to the glass transition temperature for the surrounding molten glass-like material. An annealing afterbody then cools the glass slowly from the glass transition temperature through the annealing temperature range to form a solid self-supporting glass casing. This allows thermally induced strains to relax by viscous deformations as the molten glass cools and prevents fracturing of the resulting glass liner. The quality of the glass lining is improved, along with its ability to provide a rigid impermeable casing in unstable rock formations.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://news.nationalgeographic.com/news/2002/05/0501_020502_himalaya.html"><span id="translatedtitle"><span class="hlt">Melting</span> Himalayan Glaciers May Doom Towns</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p></p> <p></p> <p>This news article describes how mountain lakes in Nepal and Bhutan have become so overfilled by water from <span class="hlt">melting</span> glaciers that they are in danger of overflowing. Scientists from the United Nations Environment Program (UNEP), along with remote-sensing experts from the International Center for Integrated Mountain Development (ICIMOD), predict that in the next half decade or so, the Himalayas could experience intense flooding as mountain lakes overflow with water from glaciers and snowfields which are <span class="hlt">melting</span> as a result of gradually rising global temperatures.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015AMTD....8.5615J"><span id="translatedtitle">The microwave properties of simulated <span class="hlt">melting</span> precipitation particles: sensitivity to initial <span class="hlt">melting</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Johnson, B. T.; Olson, W. S.; Skofronick-Jackson, G.</p> <p>2015-06-01</p> <p>A simplified approach is presented for assessing the microwave response to the initial <span class="hlt">melting</span> of realistically-shaped ice particles. This paper is divided into two parts: (1) a description of the Single Particle <span class="hlt">Melting</span> Model (SPMM): a heuristic <span class="hlt">melting</span> simulation for ice-phase precipitation particles of any shape or size. SPMM is applied to two simulated aggregate snow particles, simulating <span class="hlt">melting</span> up to 0.15 <span class="hlt">melt</span> fraction by mass; and (2) the computation of the single-particle microwave scattering and extinction properties these hydrometeors, using the discrete dipole approximation (via DDSCAT), at the following selected frequencies: 13.4, 35.6, 94.0 GHz for radar applications; and 89, 165.0 and 183.31 GHz for radiometer applications. These selected frequencies are consistent with current microwave remote sensing platforms, such as CloudSat and the Global Precipitation Measurement (GPM) mission. Comparisons with calculations using variable-density spheres indicate significant deviations in scattering and extinction properties throughout the initial range of <span class="hlt">melting</span> (liquid volume fractions less than 0.15). Integration of the single-particle properties over an exponential particle-size distribution provides additional insight into idealized radar reflectivity and passive microwave brightness temperature sensitivity to variations in size/mass, shape, <span class="hlt">melt</span> fraction, and particle orientation.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19890005673&hterms=Modern+Techniques+Raman+Spectroscopy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DModern%2BTechniques%2BRaman%2BSpectroscopy"><span id="translatedtitle">Experimental correlation of <span class="hlt">melt</span> structures, nucleation rates, and thermal histories of silicate <span class="hlt">melts</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Boynton, W. V.; DRAKE; HILDEBRAND; JONES; LEWIS; TREIMAN; WARK</p> <p>1987-01-01</p> <p>The theory and measurement of the structure of liquids is an important aspect of modern metallurgy and igneous petrology. Liquid structure exerts strong controls on both the types of crystals that may precipitate from <span class="hlt">melts</span> and on the chemical composition of those crystals. An interesting aspect of <span class="hlt">melt</span> structure studies is the problem of <span class="hlt">melt</span> memories; that is, a <span class="hlt">melt</span> can retain a memory of previous thermal history. This memory can influence both nucleation behavior and crystal composition. This <span class="hlt">melt</span> memory may be characterized quantitatively with techniques such as Raman, infrared and NMR spectroscopy to provide information on short-range structure. <span class="hlt">Melt</span> structure studies at high temperature will take advantage of the microgravity conditions of the Space Station to perform containerless experiments. <span class="hlt">Melt</span> structure determinations at high temperature (experiments that are greatly facilitated by containerless technology) will provide invaluable information for materials science, glass technology, and geochemistry. In conjunction with studies of nucleation behavior and nucleation rates, information relevant to nucleation in magma chambers in terrestrial planets will be acquired.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/12520147"><span id="translatedtitle">Association between hepatitis C virus <span class="hlt">core</span> protein and carotid atherosclerosis.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ishizaka, Yuko; Ishizaka, Nobukazu; Takahashi, Eiko; Unuma, Tadao; Tooda, Ei-ichi; Hashimoto, Hideki; Nagai, Ryozo; Yamakado, Minoru</p> <p>2003-01-01</p> <p>A link between certain infectious microorganisms and an increased risk of atherosclerotic disease has been suggested. By analyzing the data of subjects who had undergone general health-screening tests, a possible association between carotid atherosclerosis and seropositivity of antibody against hepatitis C virus (HCV) has been previously reported. In the present study, a possible link between carotid atherosclerosis and HCV <span class="hlt">core</span> protein positivity was assessed, because it is <span class="hlt">postulated</span> to be a better marker of viremia and thus persistent infection. Of the 1992 enrolled subjects, 496 (25%) had carotid artery plaque, and 25 (1.3%) were positive for HCV <span class="hlt">core</span> protein. Carotid artery plaque was positive in 480/1967 (24%) and 16/25 (64%) of the <span class="hlt">core</span> protein-negative and <span class="hlt">core</span> protein-positive subjects, respectively (p<0.0001 by chi(2) test). Serum concentrations of transaminases were higher in <span class="hlt">core</span> protein-positive subjects, but albumin concentrations were not significantly different between the 2 groups. Multivariate logistic regression analysis showed that HCV <span class="hlt">core</span> protein positivity is an independent predictor of carotid plaque with an odds ratio of 5.61 (95% confidence interval 2.06-15.26, p<0.001). These data further support the possible link between persistent HCV infection and carotid atherosclerosis in the subjects without severe liver dysfunction. PMID:12520147</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.1620K"><span id="translatedtitle">Compositional variation versus partial <span class="hlt">melting</span>: What is the cause of low velocity and high conductivity?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karato, Shun-ichiro</p> <p>2013-04-01</p> <p>The causes for low velocity, high conductivity regions of Earth (asthenosphere in the upper mantle, some regions of the D" layer at the bottom of the mantle) are controversial. I will discuss two possible causes: anomalies in chemical composition and presence of liquids (e.g., partial <span class="hlt">melt</span>). Based on the thermodynamics and the physics of <span class="hlt">melt</span> generation and migration, I will discuss the difficulties of partial <span class="hlt">melt</span> model to explain geophysical anomalies. A brief review will be presented about the hydrogen-based model for geophysical anomalies including a new theory on the relationship between isotope diffusion and conductivity, and the role of grain-boundary sliding to affect seismic wave velocities. I conclude that the variation in hydrogen content is the most plausible explanation for the anomalies in the upper mantle and the transition zone. However, hydrogen model unlikely explains the observed very large velocity reduction in the ultra-low velocity regions in the D" layer. Fe-enrichment is a possible cause for low velocity and high conductivity. However, difficulties with this model are (i) the <span class="hlt">core</span> is under-saturated with oxygen and hence the mantle next to the <span class="hlt">core</span> must be depleted with FeO, and (ii) previously proposed mechanisms of Fe penetration are inefficient. A new finding in my lab shows that FeO-depletion at the bottom of the mantle likely promotes the penetration of molten iron leading to the low velocity and high conductivity.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20120003149&hterms=Pascal+Blaise&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3D%2528Pascal%2BBlaise%2529"><span id="translatedtitle">Constraints on the Parental <span class="hlt">Melts</span> of Enriched Shergottites from Image Analysis and High Pressure Experiments</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Collinet, M.; Medard, E.; Devouard, B.; Peslier, A.</p> <p>2012-01-01</p> <p>Martian basalts can be classified in at least two geochemically different families: enriched and depleted shergottites. Enriched shergottites are characterized by higher incompatible element concentrations and initial Sr-87/Sr-86 and lower initial Nd-143/Nd-144 and Hf-176/Hf-177 than depleted shergottites [e.g. 1, 2]. It is now generally admitted that shergottites result from the <span class="hlt">melting</span> of at least two distinct mantle reservoirs [e.g. 2, 3]. Some of the olivine-phyric shergottites (either depleted or enriched), the most magnesian Martian basalts, could represent primitive <span class="hlt">melts</span>, which are of considerable interest to constrain mantle sources. Two depleted olivine-phyric shergottites, Yamato (Y) 980459 and Northwest Africa (NWA) 5789, are in equilibrium with their most magnesian olivine (Fig. 1) and their bulk rock compositions are inferred to represent primitive <span class="hlt">melts</span> [4, 5]. Larkman Nunatak (LAR) 06319 [3, 6, 7] and NWA 1068 [8], the most magnesian enriched basalts, have bulk Mg# that are too high to be in equilibrium with their olivine megacryst <span class="hlt">cores</span>. Parental <span class="hlt">melt</span> compositions have been estimated by subtracting the most magnesian olivine from the bulk rock composition, assuming that olivine megacrysts have partially accumulated [3, 9]. However, because this technique does not account for the actual petrography of these meteorites, we used image analysis to study these rocks history, reconstruct their parent magma and understand the nature of olivine megacrysts.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20100030621&hterms=Seasons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DSeasons"><span id="translatedtitle">Recent Changes in Arctic Sea Ice <span class="hlt">Melt</span> Onset, Freeze-Up, and <span class="hlt">Melt</span> Season Length</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Markus, Thorsten; Stroeve, Julienne C.; Miller, Jeffrey</p> <p>2010-01-01</p> <p>In order to explore changes and trends in the timing of Arctic sea ice <span class="hlt">melt</span> onset and freeze-up and therefore <span class="hlt">melt</span> season length, we developed a method that obtains this information directly from satellite passive microwave data, creating a consistent data set from 1979 through present. We furthermore distinguish between early <span class="hlt">melt</span> (the first day of the year when <span class="hlt">melt</span> is detected) and the first day of continuous <span class="hlt">melt</span>. A similar distinction is made for the freeze-up. Using this method we analyze trends in <span class="hlt">melt</span> onset and freeze-up for 10 different Arctic regions. In all regions except for the Sea of Okhotsk, which shows a very slight and statistically insignificant positive trend (O.4 days/decade), trends in <span class="hlt">melt</span> onset are negative, i.e. towards earlier <span class="hlt">melt</span>. The trends range from -1.0day/decade for the Bering Sea to -7.3 days/decade for the East Greenland Sea. Except for the Sea of Okhotsk all areas also show a trend towards later autumn freeze onset. The Chukchi/Beaufort Seas and Laptev/East Siberian Seas observe the strongest trends with 7 days/decade. For the entire Arctic, the <span class="hlt">melt</span> season length has increased by about 20 days over the last 30 years. Largest trends of over 1O days/decade are seen for Hudson Bay, the East Greenland Sea the Laptev/East Siberian Seas, and the Chukchi/Beaufort Seas. Those trends are statistically significant a1 the 99% level.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2003EAEJA....14182R"><span id="translatedtitle">On the rheology of crustal rocks containing low <span class="hlt">melt</span> fractions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rosenberg, C. L.; Handy, M. R.</p> <p>2003-04-01</p> <p>A review and reinterpretation of older experimental data on the deformation of partially-<span class="hlt">melted</span> granite reveals a non-linear strength decrease with increasing <span class="hlt">melt</span> fractions. This decrease is characterised by two sharp discontinuities, each reflecting a dramatic change of strength within a limited range of <span class="hlt">melt</span> fractions. A first discontinuity is shown by all experiments at <span class="hlt">melt</span> fractions between 0.0 and 0.1. The change of strength within this range of <span class="hlt">melt</span> fractions is the largest over the entire <span class="hlt">melting</span> range. The second discontinuity occurs at higher <span class="hlt">melt</span> fractions (0.4 to 0.6) and corresponds to the well known rheologically critical <span class="hlt">melt</span> percentage (RCMP). In contrast to recent interpretations, we infer that the experimental data do indicate the occurrence of the RCMP, for crystallising as well as for <span class="hlt">melting</span> rocks. However, the magnitude of the stress drop at the RCMP is negligible compared to the stress drop at <span class="hlt">melt</span> fractions < 0.1. Increasing <span class="hlt">melt</span> content in the range of <span class="hlt">melt</span> fractions between 0.0 and 0.1 induces a rapid increase in the percentage of <span class="hlt">melt</span>-bearing grain boundaries. This increase is not linear and barely existent at <span class="hlt">melt</span> fractions greater than 0.1. Therefore, the very rapid increase in the percentage of grain boundaries wetted by <span class="hlt">melt</span> is associated with a very rapid strength decrease. We therefore infer that the increasing proportion of wetted grain boundaries is the main cause for the dramatic strength drop described above. We suggest that the transition from the first strength drop to a more gentle strength decrease with increasing <span class="hlt">melt</span> fraction, is due to the formation of an interconnected network of <span class="hlt">melt</span>-bearing fractures and/or shear bands. Greater <span class="hlt">melt</span> fractions widen the putative network and further reduce the bulk strength, but to a lesser degree. The formation of a interconnected network of <span class="hlt">melt</span> films and fractures at <span class="hlt">melt</span> fractions <= 0.1 does not disrupt the solid framework. This disruption occurs at the RCMP, at <span class="hlt">melt</span> fractions >= 0.4, as proposed by several experimentalists. We suggest that the attainment of a <span class="hlt">melt</span> fraction of 0.03 to 0.08 will control the large-scale localisation of deformation into partially-<span class="hlt">melted</span> crustal layers, irrespective of the attainment of the RCMP. If the RCMP is achieved, however, the large-scale deformational response of the crust may not be different than that of a crust containing a <span class="hlt">melt</span> fraction of 0.1. Instead, the RCMP controls localisation of flow within magmatic bodies, where it effects the internal dynamics of magma chambers.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/25456786"><span id="translatedtitle">The body has a brake: micrin is a <span class="hlt">postulated</span> new gonadal hormone curbing tissue overgrowth and restricting reproduction.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hart, John E</p> <p>2014-12-01</p> <p>There is evidence for an unrecognised classical hormone secreted by the mammalian gonad. This <span class="hlt">postulated</span> hormone--'micrin' (pronounced 'my-crin')--represents the body's brake against tissue overgrowth. When oestrogens are administered in high doses to female rats there is a considerable (non-artefactual) increase in the relative size and weight of organs such as the pituitary, adrenals, uterus and liver--suggesting an organotrophic (organ-building) role for endogenous oestrogens. This effect is exaggerated if the animals are first ovariectomized, indicating the removal of a negative ovarian factor, micrin. These organ enlargements can be reduced by pretreating the rats with large doses of antioestrogens such as clomiphene and tamoxifen. This antiestrogenic blockade of exogenous oestrogens is itself blunted by prior removal of the ovaries. It is proposed that antioestrogens (e.g. tamoxifen in breast cancer treatment) antagonize the organotrophic effects of oestrogens by competing for the oestrogen receptor peripherally and centrally and via an increase in the secretion of ovarian micrin. It is deduced that micrin is the testicular 'inhibin' proposed in the 1930s, not the molecule that now bears that name, which acts at the pituitary tier as a downregulator of follicle-stimulating hormone. The hallmark of micrin deficiency in the male rat is a pituitary hypertrophy that follows castration. This is reversible with a steroid-depleted aqueous bovine testicular extract, the micrin within which suppresses the hypothalamus, normalizing the pituitary. Micrin probably acts as a brake on peripheral tissues directly but also indirectly at the meta-level via the hypothalamic-pituitary axis, resetting a hypothalamic 'organostat' controlling organ and tissue masses, part of the 'organotrophic system' of internal size regulation. Besides endocrine (circulating) micrin from the gonads there is probably paracrine (locally acting) micrin produced in the brain. This is involved in a somatic cueing system for puberty: the brake comes off at an appropriate body tissue mass disinhibiting the hypothalamus and accelerating the organism towards sexual maturity and full adult stature. This suggests the use in reproductive disorders of micrin-related drugs. These could also be inhibitors of breast, prostate and other cancers, while protecting the bone marrow via a trophic effect on the adrenals (the lack of which protection causes lethal bone marrow depression in oestrogen-treated ferrets and dogs). Benign prostatic hyperplasia is asserted to be a micrin deficiency disorder, involving insufficiently opposed androgen. The rise in cancers with age could be associated with a reduction in micrin protection and a relative lack of this hormone could partly explain why men die younger than women. Micrin is dissimilar in activity to any known molecule and could usefully be isolated, characterised and exploited therapeutically. PMID:25456786</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/5955421"><span id="translatedtitle">MORECA: A computer code for simulating modular high-temperature gas-cooled reactor <span class="hlt">core</span> heatup accidents</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ball, S.J. (Oak Ridge National Lab., TN (United States))</p> <p>1991-10-01</p> <p>The design features of the modular high-temperature gas-cooled reactor (MHTGR) have the potential to make it essentially invulnerable to damage from <span class="hlt">postulated</span> <span class="hlt">core</span> heatup accidents. This report describes the ORNL MORECA code, which was developed for analyzing <span class="hlt">postulated</span> long-term <span class="hlt">core</span> heatup scenarios for which active cooling systems used to remove afterheat following the accidents can be assumed to the unavailable. Simulations of long-term loss-of-forced-convection accidents, both with and without depressurization of the primary coolant, have shown that maximum <span class="hlt">core</span> temperatures stay below the point at which any significant fuel failures and fission product releases are expected. Sensitivity studies also have been done to determine the effects of errors in the predictions due both to uncertainties in the modeling and to the assumptions about operational parameters. MORECA models the US Department of Energy reference design of a standard MHTGR.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/60582734"><span id="translatedtitle">Fuel Rod <span class="hlt">Melt</span> Progression Simulation Using Low-Temperature <span class="hlt">Melting</span> Metal Alloy</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Seung Dong Lee; Kune Y. Suh; Un Chul Lee</p> <p>2002-01-01</p> <p>The TMI-2 accident and various severe fuel damage experiments have shown that <span class="hlt">core</span> damage is likely to proceed through various states before the <span class="hlt">core</span> slumps into the lower head. Numerous experiments were conducted to address when and how the <span class="hlt">core</span> can lose its original geometry, what geometries are formed, and in what processes the <span class="hlt">core</span> materials are transported to the</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/20748618"><span id="translatedtitle">A TEM analysis of nanoparticulates in a Polar ice <span class="hlt">core</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Esquivel, E.V.; Murr, L.E</p> <p>2004-03-15</p> <p>This paper explores the prospect for analyzing nanoparticulates in age-dated ice <span class="hlt">cores</span> representing times in antiquity to establish a historical reference for atmospheric particulate regimes. Analytical transmission electron microscope (TEM) techniques were utilized to observe representative ice-<span class="hlt">melt</span> water drops dried down on carbon/formvar or similar coated grids. A 10,000-year-old Greenland ice <span class="hlt">core</span> was <span class="hlt">melted</span>, and representative water drops were transferred to coated grids in a clean room environment. Essentially, all particulates observed were aggregates and either crystalline or complex mixtures of nanocrystals. Especially notable was the observation of carbon nanotubes and related fullerene-like nanocrystal forms. These observations are similar with some aspects of contemporary airborne particulates including carbon nanotubes and complex nanocrystal aggregates.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/21016362"><span id="translatedtitle">The Results From the First High-Pressure <span class="hlt">Melt</span> Ejection Test Completed in the Molten Fuel Moderator Interaction Facility at Chalk River Laboratories</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Nitheanandan, T.; Kyle, G.; O'Connor, R.; Sanderson, DB. [Chalk River Laboratories, Atomic Energy of Canada Limited, Chalk River, Ontario, Canada, K0J 1J0 (Canada)</p> <p>2006-07-01</p> <p>A high-pressure <span class="hlt">melt</span> ejection test using prototypical corium was conducted at Atomic Energy of Canada Limited Chalk River Laboratories. This test was planned by the CANDU Owners Group to study the potential for an energetic interaction between molten fuel and water under <span class="hlt">postulated</span> single-channel flow-blockage events. The experiments were designed to address regulator concerns surrounding this very low probability <span class="hlt">postulated</span> accident events in CANDU Pressurized Heavy Water Reactors. The objective of the experimental program is to determine whether a highly energetic 'steam explosion' and associated high-pressure pulse, is possible when molten material is finely fragmented as it is ejected from a fuel channel into the heavy-water moderator. The finely fragmented <span class="hlt">melt</span> particles would transfer energy to the moderator as it is dispersed, creating a modest pressure pulse in the calandria vessel. The high-pressure <span class="hlt">melt</span> ejection test consisted of heating up a {approx} 5 kg thermite mixture of U, U{sub 3}O{sub 8}, Zr, and CrO{sub 3} inside a 1.14-m length of insulated pressure tube. When the molten material reached the desired temperature of {approx} 2400 deg C, the pressure inside the tube was raised to 11.6 MPa, failing the pressure tube at a pre-machined flaw, and releasing the molten material into the surrounding tank of 68 deg C water. The experiment investigated the dynamic pressure history, debris size, and the effects of the material interacting with tubes representing neighbouring fuel channels. The measured mean particle size was 0.686 mm and the peak dynamic pressures were between 2.54 and 4.36 MPa, indicating that an energetic interaction between the <span class="hlt">melt</span> and the water did not occur in the test. (authors)</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2006AGUFM.V51B1665P"><span id="translatedtitle">Crystallization of An-rich plagioclase in 'dacitic' <span class="hlt">melt</span> at Arenal volcano: Natural occurrence and experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parat, F.; Streck, M.; Holtz, F.; Almeev, R.</p> <p>2006-12-01</p> <p>High-An plagioclase (An85-94) is ubiquitous in crystal-rich basaltic andesitic lavas of the current eruption and of the entire eruptive history of Arenal volcano, Costa Rica. An85-91 plagioclase was found to host glassy <span class="hlt">melt</span> inclusions of dacitic composition suggesting that high An plagioclase may also crystallize in <span class="hlt">melts</span> as silicic as ~63 wt.% SiO2 (Streck &Wacaster, 2006). Such dacitic <span class="hlt">melt</span> inclusion compositions resemble dacite tephra units that erupted a few times in Arenal's history. We investigated one pumice clast from the dacitic ET2 tephra (e.g. Borgia et al., 1988) to shed light on the possibility to crystallize high An plagioclase from dacitic <span class="hlt">melt</span>. The natural ET2 pumice sample is phenocryst poor (~7 wt.%) with a fine-grained, vesicular, and mostly crystalline matrix. Phenocrysts are dominated by plagioclase with subordinate amphibole, pyroxenes and oxides. Apatite occurs as accessory phase. Plagioclase <span class="hlt">cores</span> indeed display high An between An94 to An85. On the other hand, rim compositions tend to be significantly less anorthitic (~An75 to 65). A natural glass made from a split of the natural ET2 pumice clast was utilized as starting material for an experimental investigation into phase equilibria of this dacite magma. The first experiments were carried out at high pressure (4 kbar), high temperature (900-950°C) and water-rich conditions (4-9 wt.% H2O in <span class="hlt">melt</span>) in an internally heated pressure vessel (?logfO2~NNO+3). Plagioclase with up to 83 mole % anorthite crystallizes at 900°C and for H2Omelt=9 wt.% (water-saturated). An-rich plagioclase coexists with amphibole (Mg#~70) and magnetite (Xulvo=10) in 60 wt.% SiO2 <span class="hlt">melt</span>. As expected, An content increases with increasing temperature and water content in the <span class="hlt">melt</span>. At 950°C, current experiments found plagioclase (An75) to be stable with H2Omelt<6.4 wt.% (no plagioclase at water-saturated conditions, only magnetite crystallizes). We infer that plagioclase begins crystallizing at H2Omelt = 8 wt.% and is stable at lower H2Omelt cocrystallizing with orthopyroxene (Mg#=60-75), clinopyroxene (Mg#<76) and magnetite (Xulvo=11-29) with the anorthite content decreasing to An55 at H2Omelt = 4.9 wt.%. Our results to date already show that water-rich dacitic <span class="hlt">melt</span> at relatively high pressure and high temperature may indeed crystallize An-rich plagioclase at onset of plagioclase crystallization with or without amphibole depending on temperature. Borgia et al. 1988-Bull Volcanol, 50,86-105; Streck &Wacaster, 2006-JVGR, in press.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFM.V53C4867R"><span id="translatedtitle">Slab and Sediment <span class="hlt">Melting</span> during Subduction Initiation: Mantle Plagiogranites from the Oman Ophiolite</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rollinson, H. R.</p> <p>2014-12-01</p> <p>Granitoid dykes up to several hundred metres wide and 2 km long are found in depleted harzburgites in the mantle section of the Oman ophiolite. They vary in composition from tonalite to potassic granite and are generally more potassic than the crustal plagiogranites found within the sheeted dyke complex higher up within the ophiolite stratigraphy. Some granites are strongly peraluminous and contain garnet and andalusite. They are geochemically variable, some with REE that are relatively unfractionated ((La/Yb)n= 3.5-6.0, flat middle to heavy REE, steep light REE) to those which are highly fractionated ((La/Yb)n= 28-220). On primitive-mantle normalised plots some have very high concentrations of fluid-mobile elements - Cs, Rb, Th, U and Pb. Few have significant Ta-Nb anomalies. On the Ca-Fe-Mg-Ti discrimination diagram of Patino Douce (J. Petrol., 1999) whole-rock compositions define a spectrum between felsic-pelite derived <span class="hlt">melts</span> and amphibolite-derived <span class="hlt">melts</span>. There is a chemical similarity between the least REE fractionated plagiogranites (generally tonalites and granodiorites) and <span class="hlt">melts</span> of an amphibolitic parent. This is supported by the occurrence of mafic xenoliths in some dykes, the presence of hornblende and highly calcic <span class="hlt">cores</span> (up to An85) in some plagioclase grains. Trace element modelling using Oman Geotimes lavas as the starting composition indicates that <span class="hlt">melting</span> took place in the garnet stability field, although enrichment in the <span class="hlt">melt</span> in Cs, Rb, Ba and Pb suggests that there was another component present in addition to the mafic parent. Other plagiogranites (trondhjemites and granites) have a strongly peraluminous chemistry and mineralogy and geochemical similarities with the Himalayan leucogranites implying that they were derived from a sedimentary protolith. These mantle plagiogranites are more prevalent in the northern outcrops of the ophiolite. The volume of granitoid <span class="hlt">melt</span> and the depth of <span class="hlt">melting</span> preclude their derivation from the sole of the ophiolite, rather they were derived during subduction by the partial <span class="hlt">melting</span> of the slab and associated sediment and emplaced into the overlying mantle wedge. Current subduction-initiation models for supra-subduction ophiolites should integrate this process into their thinking.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014EGUGA..1613554F"><span id="translatedtitle"><span class="hlt">Melt</span> segregation in a gabbroic intrusion studied by means of AMS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Floess, David; Caricchi, Luca; Wallis, Simon</p> <p>2014-05-01</p> <p>The Miocene Muroto Gabbroic Intrusion (MGI) at Cape Muroto, Japan is a layered sill and displays spectacular evidence of <span class="hlt">melt</span> segregation (Yoshizawa, 1953). Felsic <span class="hlt">melts</span> separated from the mafic mush to form individual, anorthositic <span class="hlt">melt</span> lenses in the central portions of the 230m thick sill. We sampled across the entire sill at intervals of 10m, with a special focus on the zone displaying <span class="hlt">melt</span> lenses (5m sample interval). Oriented hand specimens were <span class="hlt">cored</span> in the lab for measurement of the Anisotropy of Magnetic Susceptibility (AMS). Bulk susceptibilities range between 2.7x10-3 and 37.7x10-3 SI with a mean value of 16.3x10-3 ± 7.2x10-3 SI. The degree of anisotropy (Pj) is predominantly low (<1.12) and the highest values can be found in the center of the MGI. The shape parameter (T) ranges from oblate (0.95) to prolate (-0.9) but its distribution is not random throughout the sill. T switches from predominantly prolate to oblate at around 75m from the bottom of the sill. From 150m above the bottom to the top of the sill, T is more variable. The orientation of the major axis of the AMS ellipsoid (K1) is relatively variable throughout the sill but steadily converges to a sub-horizontal orientation between 50m and 110m from the bottom. The minor axis (K3) is mainly subvertical, when K1 is horizontal. Field and thin section observations suggest that the sill did not record intense deformation after solidification. Bulk susceptibilities and thermomagnetic curves suggest that the AMS signal is dominated by titaniferous magnetite. <span class="hlt">MELTS</span> (Gualda et al. 2012) modeling indicates the crystallization of Fe-Ti oxide at 1075°C upon cooling of the sill, a temperature corresponding to a crystal fraction of ~0.55. Hence, crystallization of the AMS signal carrier occurs once the silicates formed a rigid framework. Crystallization of the AMS signal carrier in the residual, <span class="hlt">melt</span>-filled pore space may record valuable information about the separation of <span class="hlt">melt</span> from a partially crystallized mush. In the MGI, this is supported by the conspicuous AMS parameters and orientations towards the central portion of the sill, where <span class="hlt">melt</span> segregation is evident from field observations. Gualda et al., 2012, J.Pet, v. 53, p. 875-890. Yoshizawa, 1953, Mem.Col.Sci.Univ.Kyoto, v. 20, p. 271-284.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://repository.tamu.edu/handle/1969.1/94247"><span id="translatedtitle">Energy Savings in Electric Arc Furnace <span class="hlt">Melting</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lubbeck, W.</p> <p>1982-01-01</p> <p>Arc furnace <span class="hlt">melting</span> which at one time was almost exclusively used to produce alloy steel and steel castings is now widely accepted in the industry as an efficient process to produce all types of steel and iron. Presently, about 28% of steel...</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/51290294"><span id="translatedtitle">Mantle Mineral\\/Silicate <span class="hlt">Melt</span> Partitioning</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>E. A. McFarlane; M. J. Drake</p> <p>1992-01-01</p> <p>Introduction: The partitioning of elements among mantle phases and silicate <span class="hlt">melts</span> is of interest in unraveling the early thermal history of the Earth. It has been proposed that the elevated Mg\\/Si ratio of the upper mantle of the Earth is a consequence of the flotation of olivine into the upper mantle (Agee and Walker, 1988). Agee and Walker (1988) have</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=ERIC&redirectUrl=http://eric.ed.gov/?q=%22Summer+Melt%22&id=EJ1005106"><span id="translatedtitle">Can Text Messages Mitigate Summer <span class="hlt">Melt</span>?</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Castleman, Benjamin L.; Page, Lindsay C.</p> <p>2013-01-01</p> <p>Higher education officials have long been familiar with the concept of "summer <span class="hlt">melt</span>," where students who have paid a deposit to attend one college or university instead matriculate at a different institution, usually presumed to be of comparable quality. In previous research, drawing on longitudinal data from various urban school districts…</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/868289"><span id="translatedtitle">Method for the <span class="hlt">melting</span> of metals</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>White, Jack C. (Albany, OR); Traut, Davis E. (Corvallis, OR)</p> <p>1992-01-01</p> <p>A method of quantitatively determining the molten pool configuration in <span class="hlt">melting</span> of metals. The method includes the steps of introducing hafnium metal seeds into a molten metal pool at intervals to form ingots, neutron activating the ingots and determining the hafnium location by radiometric means. Hafnium possesses exactly the proper metallurgical and radiochemical properties for this use.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2013EGUGA..15.5267S"><span id="translatedtitle">Formation of <span class="hlt">melt</span> channels on ice shelves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sergienko, Olga</p> <p>2013-04-01</p> <p><span class="hlt">Melt</span> channels have been observed on ice shelves experiencing strong <span class="hlt">melting</span> in both Greenland (Petermann Glacier) and Antarctica (Pine Island Glacier). Using a fully-couple ice-shelf/sub-ice-shelf-ocean flow model, it is demonstrated that these channels can form spontaneously in laterally confined ice shelves. These channels have transverse extent of a few kilometers and a vertical relief of about a few hundred meters. Meltrates and sea-water transport in the channels are significantly higher than in between the channels on the smooth flat ice bottom. In circumstances where an ice shelf has no-slip conditions at its lateral boundaries, the ice-shelf/sub-ice-shelf-cavity system exhibits equilibrium periodic states, where the same configurations repetitively appear with a periodicity of about 30-35 years. This peculiar dynamics of the system has strong implications on the interpretation of the remote and in-situ observations and inferences of the system parameters (e.g., <span class="hlt">melt</span> rates) based on these observations. For instance, the persistent temporal changes in the ice-shelf thickness are caused by internal dynamics of the <span class="hlt">melt</span> channels, and, in contrast to traditional interpretation, can be independent of the oceanic forcings.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015PolSc...9...94O"><span id="translatedtitle">Ice <span class="hlt">melting</span> and earthquake suppression in Greenland</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Olivieri, M.; Spada, G.</p> <p>2015-03-01</p> <p>It has been suggested that the Greenland ice sheet is the cause of earthquake suppression in the region. With few exceptions, the observed seismicity extends only along the continental margins of Greenland, which almost coincide with the ice sheet margin. This pattern has been put forward as further validation of the earthquake suppression hypothesis. In this review, new evidence in terms of ice <span class="hlt">melting</span>, post-glacial rebound and earthquake occurrence is gathered and discussed to re-evaluate the connection between ice mass unloading and earthquake suppression. In Greenland, the spatio-temporal distribution of earthquakes indicates that seismicity is mainly confined to regions where the thick layer of ice is absent and where significant ice <span class="hlt">melting</span> is presently occurring. A clear correlation between seismic activity and ice <span class="hlt">melting</span> in Greenland is not found. However, earthquake locations and corresponding depth distributions suggest two distinct governing mechanisms: post-glacial rebound promotes moderate-size crustal earthquakes at Greenland's regional scale, while current ice <span class="hlt">melting</span> promotes shallow low magnitude seismicity locally.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/61148841"><span id="translatedtitle">BATCH CALCINATION STUDIES-<span class="hlt">MELT</span> FORMATION</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Shefcik</p> <p>1961-01-01</p> <p>It is shown that the formation of a meltable calcine by batch ; calcination of an acidic waste solution containing primary sodium, iron, and ; aluminum sulfate and nitrate can be predicted. Calcine <span class="hlt">melting</span> at temperatures ; less than 900 deg C can be correlated with the sodium to metal ion ratio and the ; sulfate to salt nitrate ratio.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://www.cosee.net/best_activities/activity/Causes_and_Effects_of_Melting_Ice.pdf"><span id="translatedtitle">Causes and Effects of <span class="hlt">Melting</span> Ice</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p>Elizabeth Vernon Bell</p> <p>2012-11-14</p> <p>In this activity, learners explore the concept of density-driven currents (thermohaline circulation) and how these currents are affected by climate change. Learners use colored ice cubes, water, and salt to explore density as it relates to salinity. This activity helps learners to understand the impact of glacial <span class="hlt">melt</span> on sea level rise.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/57499077"><span id="translatedtitle"><span class="hlt">Melt</span> Flow Instabilities of Wood Polymer Composites</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Velichko Hristov</p> <p>2009-01-01</p> <p><span class="hlt">Melt</span> flow instabilities during extrusion of wood polymer composites (WPC) containing 30–60 wt% wood flour (WF) have been investigated. The research emphasized elucidation of the extrudate surface tearing mechanism and its relation to wall slip. This interesting phenomenon has been known in the WPC industry for years; however, it has not received much research interest. It was observed that increasing</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://oaktrust.library.tamu.edu//handle/1969.1/94247"><span id="translatedtitle">Energy Savings in Electric Arc Furnace <span class="hlt">Melting</span> </span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Lubbeck, W.</p> <p>1982-01-01</p> <p>Arc furnace <span class="hlt">melting</span> which at one time was almost exclusively used to produce alloy steel and steel castings is now widely accepted in the industry as an efficient process to produce all types of steel and iron. Presently, about 28% of steel...</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2010EGUGA..12.9669K"><span id="translatedtitle">Continuous analysis of phosphate in a Greenland shallow ice <span class="hlt">core</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kjær, Helle Astrid; Svensson, Anders; Bigler, Matthias; Vallelonga, Paul; Kettner, Ernesto; Dahl-Jensen, Dorthe</p> <p>2010-05-01</p> <p>Phosphate is an important and sometimes limiting nutrient for primary production in the oceans. Because of deforestation and the use of phosphate as a fertilizer changes in the phosphate cycle have occurred over the last centuries. On longer time scales, sea level changes are thought to have also caused changes in the phosphate cycle. Analyzing phosphate concentrations in ice <span class="hlt">cores</span> may help to gain important knowledge about those processes. In the present study, we attach a phosphate detection line to an existing continuous flow analysis (CFA) setup for ice <span class="hlt">core</span> analysis at the University of Copenhagen. The CFA system is optimized for high-resolution measurements of insoluble dust particles, electrolytic <span class="hlt">melt</span> water conductivity, and the concentrations of ammonium and sodium. For the phosphate analysis we apply a continuous and highly sensitive absorption method that has been successfully applied to determine phosphate concentrations of sea water (Zhang and Chi, 2002). A line of <span class="hlt">melt</span> water from the CFA <span class="hlt">melt</span> head (1.01 ml per minute) is combined with a molybdate blue reagent and an ascorbic acid buffer. An uncompleted reaction takes place in five meters of heated mixing coils before the absorption measurement at a wavelength of 710 nanometer takes place in a 2 m long liquid waveguide cell (LWCC) with an inner volume of 0.5 ml. The method has a detection limit of around 0.1 ppb and we are currently investigating a possible interference from molybdate reacting with silicates that are present in low amounts in the ice. Preliminary analysis of early Holocene samples from the NGRIP ice <span class="hlt">core</span> show phosphate concentration values of a few ppb. In this study, we will attempt to determine past levels of phosphate in a shallow Northern Greenland firn <span class="hlt">core</span> with an annual layer thickness of about 20 cm ice equivalent. With a <span class="hlt">melt</span> speed of 2.5 cm ice per minute our method should allow the resolution of any seasonal variability in phosphate concentrations.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=20000000520&hterms=earth+core&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dearth%2Bcore"><span id="translatedtitle">Element Partitioning Constraints on Formation and Composition of the Earth's <span class="hlt">Core</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Li, J.; Agee, C. B.; Fei, Y.</p> <p>1998-01-01</p> <p>Element partitioning study provides a number of constraints on the formation and composition of the <span class="hlt">core</span>. First, partitioning of siderophile elements between the <span class="hlt">core</span> and mantle should explain the "excess" siderophile elements in the mantle. Second, partitioning of light element(s) between the <span class="hlt">core</span> and mantle should supply the <span class="hlt">core</span> with the right amount of light element(s) to account for the density deficit in the <span class="hlt">core</span>. Third, partitioning of light element(s) between the inner and outer <span class="hlt">core</span> should be consistent with the observed difference in density deficits (relative to pure Fe) between these two reservoirs. In this study, high-pressure and high-temperature experiments have been conducted to investigate the pressure, temperature, and composition effects on partitioning of siderophile elements Ni and Co between <span class="hlt">core</span>-forming Fe alloy and mantle silicate <span class="hlt">melt</span> and minerals, partitioning of light elements S, O, and Si between <span class="hlt">core</span>-forming Fe alloy and mantle silicate <span class="hlt">melt</span> and minerals, and partitioning of light elements S and C between solid and liquid Fe. The implications of these results for mechanism of <span class="hlt">core</span> formation and the composition of the <span class="hlt">core</span> are discussed.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2010EGUGA..1210223G"><span id="translatedtitle">Lithospheric Architecture, Heterogenities, Instabilities, <span class="hlt">Melting</span> - insight form numerical modelling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gorczyk, Weronika; Hobbs, Bruce; Ord, Alison; Gessner, Klaus; Gerya, Taras V.</p> <p>2010-05-01</p> <p>The seismological structure of the Earth's lithosphere is identified to be strongly heterogeneous in terms of thermal and rheological structures. Lithospheric discontinuities (sharp changes in the thermal and/or compositional structure) are thought to be long lived and are mostly correlated with major tectonic boundaries that commonly have been reactivated and which subsequently are the foci of magma intrusion and major mineralization. Resent studies have shown that mantle metasomatism is also controlled by such boundaries. This paper explores the control that lithospheric heterogeneity exerts on the thermal and chemical evolution during deformation subsequent to the development of the heterogeneity. We explore the behaviour of the rheological heterogeneous lithosphere in a compressional regime. The occurrence of such variations may be caused for instance by amalgamation of micro-continents such as is thought to be characteristic of the Yilgarn, Western Australia or South Africa. Theses micro-continents, due to diverse histories may be characterised by various thermal and rheological structures. The models are simplistic but illustrate the basic principles. The code used in this study is based on a conservative finite-difference, multi-grid, marker in cell method. Devolatilisation reactions and <span class="hlt">melting</span> can affect the physical properties of rocks and are incorporated in a self-consistent manner. We use a petrological-thermomechanical modelling approach with all rock properties including mechanical properties calculated in the Lagrangian scheme for rock markers at every time step based on Gibbs free energy minimization as a function of the local pressure, temperature and rock composition. The results illustrate that initial structural complexity is necessary for and has a dramatic effect on fault and development, the growth of deep basins, <span class="hlt">core</span> complex formation, <span class="hlt">melting</span> and devolatilisation within the lithosphere. The horizontal and vertical variation in plastic yield stress of the blocks (representing heterogeneous fused material) nucleates localised deformation and creates conditions for delamination via a Rayleigh-Taylor instability. Above the site of localised delamination of the mantle lithosphere, a series of deep crustal faults develop that may extend into the upper mantle. These deep structures can act as the pathways for mantle derived CO2±H2O fluids and alkaline igneous complexes. Isotherms are commonly elevated throughout the lithosphere in the hanging wall of deep through-going structures and are depressed in the footwalls. This means that some architectures favour devolatilisation and <span class="hlt">melting</span> in the hanging wall. A large spectrum of behaviour is observed and results from minor changes in the orientation and strength of the blocks.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://nicl.usgs.gov/"><span id="translatedtitle">National Ice <span class="hlt">Core</span> Laboratory</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p>USGS</p> <p></p> <p>This facility stores, curates and studies ice <span class="hlt">cores</span> recovered from glaciers from around the world. The site provides a photo gallery and description about each step of the process of drilling, transporting and analyzing the <span class="hlt">core</span>. There is also a database of basic information about each <span class="hlt">core</span> held at the laboratory and links to global change research information.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://hal.archives-ouvertes.fr/docs/00/35/62/98/PDF/cahier_de_recherche_2008-29.pdf"><span id="translatedtitle"><span class="hlt">Cores</span> of combined games</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Francis Bloch; Geoffroy De Clippel</p> <p>2008-01-01</p> <p>This paper studies the <span class="hlt">core</span> of combined games, obtained by summing two coalitional games. It is shown that the set of balanced transferable utility games can be partitioned into equivalence classes of component games whose <span class="hlt">core</span> is equal to the <span class="hlt">core</span> of the combined game. On the other hand, for non balanced games, the binary relation associating two component games</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.brown.edu/Departments/Economics/Papers/2009/2009-1_paper.pdf"><span id="translatedtitle"><span class="hlt">Cores</span> of Combined Games</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Francis Bloch; Geoffroy de Clippel</p> <p>2009-01-01</p> <p>This paper studies the <span class="hlt">core</span> of combined games, obtained by summing two coalitional games. It is shown that the set of balanced transferable utility games can be partitioned into equivalence classes of component games to determine whether the <span class="hlt">core</span> of the combined game coincides with the sum of the <span class="hlt">cores</span> of its components. On the other hand, for non-balanced games,</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014NDS...118..505K"><span id="translatedtitle">Analysis of Pu Isotopes in <span class="hlt">Melted</span> Fuel by Neutron Resonance Transmission: Examination by Linear Absorption Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kitatani, F.; Harada, H.; Takamine, J.; Kureta, M.; Seya, M.</p> <p>2014-04-01</p> <p>We have been studying the feasibility of neutron resonance transmission analysis (NRTA) for quantifying nuclear materials (Pu/U isotopes) in particle-like debris of <span class="hlt">melted</span> fuel for nuclear material accountability and safeguards. The achievable measurement accuracy of NRTA was examined using a linear absorption model for the sample which contain substances other than nuclear fuel materials, such as boron and iron. The impurities (boron and iron etc.) in <span class="hlt">melted</span> fuel are from the support structure and criticality control materials of the reactor <span class="hlt">core</span>, and should be included to study the feasibility of NRTA for actual application. Neutron transmission spectra were calculated using the total neutron cross-sections in JENDL-4.0. The transmission spectra together with their uncertainties were evaluated. The study showed quantitatively that the statistical uncertainty in the determination of atomic number density of each isotope depends on the impurity density in the sample. The optimal thickness of the sample was determined for various impurity densities.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/24735303"><span id="translatedtitle">Inverse <span class="hlt">melting</span> in a two-dimensional off-lattice model.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Almudallal, Ahmad M; Buldyrev, Sergey V; Saika-Voivod, Ivan</p> <p>2014-04-14</p> <p>We carry out computer simulations of a simple, two-dimensional off-lattice model that exhibits inverse <span class="hlt">melting</span>. The monodisperse system comprises <span class="hlt">core</span>-softened disks interacting through a repulsive square shoulder located inside an attractive square well. By systematically varying the potential parameters, we increase the pressure range over which the liquid freezes to a crystal upon isobaric heating. The effect is largely controlled by the extent of the shoulder. Despite occurring in two dimensions, the <span class="hlt">melting</span> transition is first order and to a liquid, rather than to a hexatic or quasicrystal phase. We also provide comment on a commonly employed correlation function used to determine the degree of translational ordering in a system. PMID:24735303</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014JChPh.140n4505A"><span id="translatedtitle">Inverse <span class="hlt">melting</span> in a two-dimensional off-lattice model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Almudallal, Ahmad M.; Buldyrev, Sergey V.; Saika-Voivod, Ivan</p> <p>2014-04-01</p> <p>We carry out computer simulations of a simple, two-dimensional off-lattice model that exhibits inverse <span class="hlt">melting</span>. The monodisperse system comprises <span class="hlt">core</span>-softened disks interacting through a repulsive square shoulder located inside an attractive square well. By systematically varying the potential parameters, we increase the pressure range over which the liquid freezes to a crystal upon isobaric heating. The effect is largely controlled by the extent of the shoulder. Despite occurring in two dimensions, the <span class="hlt">melting</span> transition is first order and to a liquid, rather than to a hexatic or quasicrystal phase. We also provide comment on a commonly employed correlation function used to determine the degree of translational ordering in a system.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015AIPC.1657k0007O"><span id="translatedtitle"><span class="hlt">Melting</span> behaviour of gold-platinum nanoalloy clusters by molecular dynamics simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ong, Yee Pin; Lim, Thong Leng; Yoon, Tiem Leong</p> <p>2015-04-01</p> <p>The <span class="hlt">melting</span> behavior of bimetallic gold-platinum nanoclusters is studied by applying Brownian-type isothermal molecular dynamics (MD) simulation, a program modified from the cubic coupling scheme (CCS). The process begins with the ground-state structures obtained from global minimum search algorithm and proceeds with the investigation of the effect of temperature on the thermal properties of gold-platinum nanoalloy clusters. N-body Gupta potential has been employed in order to account for the interactions between gold and platinum atoms. The ground states of the nanoalloy clusters, which are <span class="hlt">core</span>-shell segregated, are heated until they become thermally segregated. The detailed <span class="hlt">melting</span> mechanism of the nanoalloy clusters is studied via this approach to provide insight into the thermal stability of the nanoalloy clusters.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://dspace.mit.edu/handle/1721.1/69467"><span id="translatedtitle">Experimental studies of <span class="hlt">melting</span> and crystallization processes in planetary interiors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Krawczynski, Michael James</p> <p>2011-01-01</p> <p><span class="hlt">Melting</span> and crystallization processes on the Earth and Moon are explored in this thesis, and the topics of <span class="hlt">melt</span> generation, transport, and crystallization are discussed in three distinct geologic environments: the Moon's ...</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/39659202"><span id="translatedtitle">Significance of Europium anomalies in silicate <span class="hlt">melts</span> and crystal-<span class="hlt">melt</span> equilibria: a re-evaluation</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>P. Möller; G. K. Muecke</p> <p>1984-01-01</p> <p>Although europium speciation in silicate <span class="hlt">melts</span> partly reflects prevailing oxygen fugacities, <span class="hlt">melt</span> composition and structure play the major role in determining Eu2+\\/ Eu3+ ratios and europium partitioning into mineral phases. Experimental evidence by different investigators on the magnitude of the compositional effect on Eu2+\\/Eu3+ provides consistent results only if account is taken of the oxygen buffer system employed in the</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2010GeCoA..74.4543P"><span id="translatedtitle">Crystallization, <span class="hlt">melt</span> inclusion, and redox history of a Martian meteorite: Olivine-phyric shergottite Larkman Nunatak 06319</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Peslier, A. H.; Hnatyshin, D.; Herd, C. D. K.; Walton, E. L.; Brandon, A. D.; Lapen, T. J.; Shafer, J. T.</p> <p>2010-08-01</p> <p>The Larkman Nunatak (LAR) 06319 olivine-phyric shergottite is composed of zoned megacrysts of olivine (Fo 76-55 from <span class="hlt">core</span> to rim), pyroxene (from <span class="hlt">core</span> to rim En 70Fs 25Wo 5, En 50Fs 25Wo 25, and En 45Fs 45Wo 10), and Cr-rich spinel in a matrix of maskelynite (An 52Ab 45), pyroxene (En 30-40Fs 40-55Wo 10-25,), olivine (Fo 50), Fe-Ti oxides, sulfides, phosphates, Si-rich glass, and baddeleyite. LAR 06319 experienced equilibration shock pressures of 30-35 GPa based on the presence of localized shock <span class="hlt">melts</span>, mechanical deformation of olivine and pyroxene, and complete transformation of plagioclase to maskelynite with no relict birefringence. The various phases and textures of this picritic basalt can be explained by closed system differentiation of a shergottitic <span class="hlt">melt</span>. Recalculated parent <span class="hlt">melt</span> compositions obtained from <span class="hlt">melt</span> inclusions located in the <span class="hlt">core</span> of the olivine megacrysts (Fo >72) resemble those of other shergottite parent <span class="hlt">melts</span> and whole-rock compositions, albeit with a lower Ca content. These compositions were used in the <span class="hlt">MELTS</span> software to reproduce the crystallization sequence. Four types of spinel and two types of ilmenite reflect changes in oxygen fugacity during igneous differentiation. Detailed oxybarometry using olivine-pyroxene-spinel and ilmenite-titanomagnetite assemblages indicates initial crystallization of the megacrysts at 2 log units below the Fayalite-Magnetite-Quartz buffer (FMQ - 2), followed by crystallization of the groundmass over a range of FMQ - 1 to FMQ + 0.3. Variation is nearly continuous throughout the differentiation sequence. LAR 06319 is the first member of the enriched shergottite subgroup whose bulk composition, and that of <span class="hlt">melt</span> inclusions in its most primitive olivines, approximates that of the parental <span class="hlt">melt</span>. The study of this picritic basalt indicates that oxidation of more than two log units of FMQ can occur during magmatic fractional crystallization and ascent. Some part of the wide range of oxygen fugacities recorded in shergottites may consequently be due to this process. The relatively reduced conditions at the beginning of the crystallization sequence of LAR 06319 may imply that the enriched shergottite mantle reservoir is slightly more reduced than previously thought. As a result, the total range of Martian mantle oxygen fugacities is probably limited to FMQ - 4 to - 2. This narrow range could have been generated during the slow crystallization of a magma ocean, a process favored to explain the origin of shergottite mantle reservoirs.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/24121545"><span id="translatedtitle">Effect of ash circulation in gasification <span class="hlt">melting</span> system on concentration and leachability of lead in <span class="hlt">melting</span> furnace fly ash.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Okada, Takashi; Suzuki, Masaru</p> <p>2013-11-30</p> <p>In some gasification-<span class="hlt">melting</span> plants, generated <span class="hlt">melting</span> furnace fly ash is returned back to the <span class="hlt">melting</span> furnace for converting the ash to slag. This study investigated the effect of such ash circulation in the gasification-<span class="hlt">melting</span> system on the concentration and leachability of lead in the <span class="hlt">melting</span> furnace fly ash. The ash circulation in the <span class="hlt">melting</span> process was simulated by a thermodynamic calculation, and an elemental analysis and leaching tests were performed on a <span class="hlt">melting</span> furnace fly ash sample collected from the gasification-<span class="hlt">melting</span> plant with the ash circulation. It was found that by the ash circulation in the gasification-<span class="hlt">melting</span>, lead was highly concentrated in the <span class="hlt">melting</span> furnace fly ash to the level equal to the fly ash from the ash-<span class="hlt">melting</span> process. The thermodynamic calculation predicted that the lead volatilization by the chlorination is promoted by the ash circulation resulting in the high lead concentration. In addition, the lead extraction from the <span class="hlt">melting</span> furnace fly ash into a NaOH solution was also enhanced by the ash circulation, and over 90% of lead in the fly ash was extracted in 5 min when using 0.5 mol l(-1) NaOH solution with L/S ratio of 10 at 100 °C. Based on the results, a combination of the gasification-<span class="hlt">melting</span> with the ash circulation and the NaOH leaching method is proposed for the high efficient lead recovery. PMID:24121545</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014Icar..228..347J"><span id="translatedtitle">Formation of <span class="hlt">melt</span> droplets, <span class="hlt">melt</span> fragments, and accretionary impact lapilli during a hypervelocity impact</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Johnson, B. C.; Melosh, H. J.</p> <p>2014-01-01</p> <p>We present a model that describes the formation of <span class="hlt">melt</span> droplets, <span class="hlt">melt</span> fragments, and accretionary impact lapilli during a hypervelocity impact. Using the iSALE hydrocode, coupled to the ANEOS equation of state for silica, we create high-resolution two-dimensional impact models to track the motion of impact ejecta. We then estimate the size of the ejecta products using simple analytical expressions and information derived from our hydrocode models. Ultimately, our model makes predictions of how the size of the ejecta products depends on impactor size, impact velocity, and ejection velocity. In general, we find that larger impactor sizes result in larger ejecta products and higher ejection velocities result in smaller ejecta product sizes. We find that a 10 km diameter impactor striking at a velocity of 20 km/s creates millimeter scale <span class="hlt">melt</span> droplets comparable to the <span class="hlt">melt</span> droplets found in the Chicxulub ejecta curtain layer. Our model also predicts that <span class="hlt">melt</span> droplets, <span class="hlt">melt</span> fragments, and accretionary impact lapilli should be found together in well preserved ejecta curtain layers and that all three ejecta products can form even on airless bodies that lack significant volatile content. This prediction agrees with observations of ejecta from the Sudbury and Chicxulub impacts as well as the presence of accretionary impact lapilli in lunar breccia.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/5554098"><span id="translatedtitle">Method and apparatus for drawing monocrystalline ribbon from a <span class="hlt">melt</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ciszek, T.F.; Schwuttke, G.H.</p> <p>1981-11-10</p> <p>A method and apparatus are described for drawing a monocrystalline ribbon or web from a <span class="hlt">melt</span> comprising utilizing a shaping die including at least two elements spaced one from the other each having a portion thereof located below the level of the <span class="hlt">melt</span> and another portion located above the level of the <span class="hlt">melt</span> a distance sufficient to form a raised meniscus of <span class="hlt">melt</span> about the corresponding element.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.dspace.cam.ac.uk/handle/1810/248591"><span id="translatedtitle">Diffusive over-hydration of olivine-hosted <span class="hlt">melt</span> inclusions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Hartley, Margaret E.; Neave, David A.; Maclennan, John; Edmonds, Marie; Thordarson, Thor</p> <p>2015-06-11</p> <p>primary <span class="hlt">melt</span> compositions. This is the first study to illustrate <span class="hlt">melt</span> inclusion hydration due to water gradi- ents set up by the mixing of <span class="hlt">melts</span> with heterogeneous mantle parents. We use diffusion modelling to calculate the timescales of diffusive... similar geochemical behaviour during mantle <span class="hlt">melting</span> and actional crystallisation (e.g. Michael, 1995; Danyushevsky et al., 00; Dixon and Clague, 2001; Saal et al., 2002; Rosenthal et al., 15). This indicates that Ce can be used as a proxy...</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/51490451"><span id="translatedtitle">On the rheology of crustal rocks containing low <span class="hlt">melt</span> fractions</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>C. L. Rosenberg; M. R. Handy</p> <p>2003-01-01</p> <p>A review and reinterpretation of older experimental data on the deformation of partially-<span class="hlt">melted</span> granite reveals a non-linear strength decrease with increasing <span class="hlt">melt</span> fractions. This decrease is characterised by two sharp discontinuities, each reflecting a dramatic change of strength within a limited range of <span class="hlt">melt</span> fractions. A first discontinuity is shown by all experiments at <span class="hlt">melt</span> fractions between 0.0 and 0.1.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53176001"><span id="translatedtitle">Rheological Consequences of Incipient <span class="hlt">Melting</span> in Crustal Rocks</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>C. L. Rosenberg</p> <p>2004-01-01</p> <p>A review and reinterpretation of older experimental data on the deformation of partially-<span class="hlt">melted</span> granite reveals a non-linear strength decrease with increasing <span class="hlt">melt</span> fractions. This decrease is characterised by two sharp discontinuities, each reflecting a dramatic change of strength within a limited range of <span class="hlt">melt</span> fractions. A first discontinuity is shown by all experiments at <span class="hlt">melt</span> fractions of approximately 0.07. The</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=DOE-PATENT-XML&redirectUrl=http://www.osti.gov/doepatents/biblio/864038"><span id="translatedtitle">Method and apparatus for drawing monocrystalline ribbon from a <span class="hlt">melt</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Ciszek, Theodore F. (Evergreen, CO); Schwuttke, Guenter H. (Poughkeepsie, NY)</p> <p>1981-11-10</p> <p>A method and apparatus for drawing a monocrystalline ribbon or web from a <span class="hlt">melt</span> comprising utilizing a shaping die including at least two elements spaced one from the other each having a portion thereof located below the level of the <span class="hlt">melt</span> and another portion located above the level of the <span class="hlt">melt</span> a distance sufficient to form a raised meniscus of <span class="hlt">melt</span> about the corresponding element.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/22111942"><span id="translatedtitle">The behavior of ANGRA 2 nuclear power plant <span class="hlt">core</span> for a small break LOCA simulated with RELAP5 code</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sabundjian, Gaiane; Andrade, Delvonei A.; Belchior, Antonio Jr.; Silva Rocha, Marcelo da; Conti, Thadeu N.; Torres, Walmir M.; Macedo, Luiz A.; Umbehaun, Pedro E.; Mesquita, Roberto N.; Masotti, Paulo H. F.; Souza Lima, Ana Cecilia de [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN - SP) Av. Professor Lineu Prestes, 2242 05508-000 Sao Paulo, SP (Brazil)</p> <p>2013-05-06</p> <p>This work discusses the behavior of Angra 2 nuclear power plant <span class="hlt">core</span>, for a <span class="hlt">postulate</span> Loss of Coolant Accident (LOCA) in the primary circuit for Small Break Loss Of Coolant Accident (SBLOCA). A pipe break of the hot leg Emergency <span class="hlt">Core</span> Cooling System (ECCS) was simulated with RELAP 5 code. The considered rupture area is 380 cm{sup 2}, which represents 100% of the ECCS pipe flow area. Results showed that the cooling is enough to guarantee the integrity of the reactor <span class="hlt">core</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://hdl.handle.net/2060/19740009815"><span id="translatedtitle">Banded transformer <span class="hlt">cores</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mclyman, C. W. T. (inventor)</p> <p>1974-01-01</p> <p>A banded transformer <span class="hlt">core</span> formed by positioning a pair of mated, similar <span class="hlt">core</span> halves on a supporting pedestal. The <span class="hlt">core</span> halves are encircled with a strap, selectively applying tension whereby a compressive force is applied to the <span class="hlt">core</span> edge for reducing the innate air gap. A dc magnetic field is employed in supporting the <span class="hlt">core</span> halves during initial phases of the banding operation, while an ac magnetic field subsequently is employed for detecting dimension changes occurring in the air gaps as tension is applied to the strap.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.agu.org/journals/gl/v021/i001/93GL03051/93GL03051.pdf"><span id="translatedtitle">Intergranular basaltic <span class="hlt">melt</span> is distributed in thin, elogated inclusions</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Ulrich H. Faul; Douglas R. Toomey; Harve S. Waff</p> <p>1994-01-01</p> <p>We describe a method to analyze the <span class="hlt">melt</span> distribution in experimentally produced ultramafic partial <span class="hlt">melts</span>. It is shown that the <span class="hlt">melt</span> inclusions can be approximated by ellipses in two dimensions and by penny-shaped ellipsoids in three dimensions. The aspect ratios of these ellipses (the ratio of the minor to the major axis) can in turn be used to calculate bulk</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53924556"><span id="translatedtitle">Modelling of <span class="hlt">melt</span> ponds on a sea ice floe</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>F. Scott; D. Feltham</p> <p>2009-01-01</p> <p>During winter the ocean surface at the poles freezes over to form sea ice. Sea ice floats on the ocean surface and has a matrix structure caused by the rejection of salts during freezing. In the summer sea ice <span class="hlt">melts</span> at its surface creating <span class="hlt">melt</span> ponds. An accurate estimate of the fraction of the upper sea-ice surface covered in <span class="hlt">melt</span></p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/8560/1/02-1084.pdf"><span id="translatedtitle">Rapid Bottom <span class="hlt">Melting</span> Widespread near Antarctic Ice Sheet Grounding Lines</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Eric Rignot; Stanley S. Jacobs</p> <p>2002-01-01</p> <p>As continental ice from Antarctica reaches the grounding line and begins to float, its underside <span class="hlt">melts</span> into the ocean. Results obtained with satellite radar interferometry reveal that bottom <span class="hlt">melt</span> rates experienced by large outlet glaciers near their grounding lines are far higher than generally assumed. The <span class="hlt">melting</span> rate is positively correlated with thermal forcing, increasing by 1 meter per year</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.umich.edu/~youxue/publications/Wang2009CMP.pdf"><span id="translatedtitle">ORIGINAL PAPER Water diffusion in Mount Changbai peralkaline rhyolitic <span class="hlt">melt</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Zhang, Youxue</p> <p></p> <p>ORIGINAL PAPER Water diffusion in Mount Changbai peralkaline rhyolitic <span class="hlt">melt</span> Haoyue Wang Æ Zhengjiu in a peralkaline rhyolitic <span class="hlt">melt</span> with major oxide concentrations matching Mount Changbai rhyolite. Combining data from this work and a related study, total water diffusivity in peralkaline rhyolitic <span class="hlt">melt</span> can</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://www.umich.edu/~youxue/publications/Liu2000EPSL.pdf"><span id="translatedtitle">Bubble growth in rhyolitic <span class="hlt">melt</span> Yang Liu, Youxue Zhang *</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Zhang, Youxue</p> <p></p> <p>Bubble growth in rhyolitic <span class="hlt">melt</span> Yang Liu, Youxue Zhang * The Department of Geological Sciences rhyolitic <span class="hlt">melt</span> with 1.4^2.0 wt% initial total H2O at 0.1 MPa and 500^600³C. Growth of many bubbles. The average growth rate for bubbles growing in an infinite rhyolitic <span class="hlt">melt</span> at a bubble radius of 25 Wm is V0</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/23266152"><span id="translatedtitle">Nanofibers from gas-assisted polymer <span class="hlt">melt</span> electrospinning</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Eduard Zhmayev; Daehwan Cho; Yong Lak Joo</p> <p>2010-01-01</p> <p>The concept of a gas-assisted polymer <span class="hlt">melt</span> electrospinning process is presented. This technique allows for reduced quenching of the <span class="hlt">melt</span> jet in the spinning region, and thus increasing the jet attenuation rate and resulting in production of sub-micron scale fibers. A comprehensive <span class="hlt">melt</span> electrospinning model was used to analyze the effects of the heated air stream on the polymer jet.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://hal.archives-ouvertes.fr/docs/00/23/23/90/PDF/ajp-jphyslet_1984_45_12_621_0.pdf"><span id="translatedtitle">Transverse acoustic phonons in germanium near the <span class="hlt">melting</span> point</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Paris-Sud XI, Université de</p> <p></p> <p>L-621 Transverse acoustic phonons in germanium near the <span class="hlt">melting</span> point B. Hennion Laboratoire Léon] and [100] up to 935 °C, only 2 degrees below the <span class="hlt">melting</span> point Tm. No evidence of softening is found are present in the crystal near the <span class="hlt">melting</span> point. J. Physique Lett. 45 (1984) L-621- L-626 15 JUIN 1984</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://web.missouri.edu/~zhangyu/Pubs/18_Zhang_Chen_Wang_IJHFF_1994.pdf"><span id="translatedtitle">TECHNICAL NOTE Analysis of <span class="hlt">melting</span> in an enclosure with</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Zhang, Yuwen</p> <p></p> <p>, e.g.. the initial solid-phase temperature is isothermal and at the <span class="hlt">melting</span> point. The solutionTECHNICAL NOTE Analysis of <span class="hlt">melting</span> in an enclosure with discrete heating at constant rate Yuwen the <span class="hlt">melting</span> process in an enclosure with one of its side walls discretely heated (Zhang et al. 1993). Since</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://materials.duke.edu/auro/AUROARTICULA/APL88-133110_2006.pdf"><span id="translatedtitle">Modeling the <span class="hlt">melting</span> of supported clusters and Arne Rosna</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Curtarolo, Stefano</p> <p></p> <p>effective diameters of supported metal clusters, so that the <span class="hlt">melting</span> point dependence on cluster size can or almost linear decreasing <span class="hlt">melting</span> point with increasing inverse cluster diameter: Tm D = TmB 1 - D , 1a Tm D = TmB 1 - D - D - 2t , 1b where Tm and TmB are the <span class="hlt">melting</span> points of the cluster and bulk</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/51660749"><span id="translatedtitle">Unmanned Aircraft System (UAS) Assessment of <span class="hlt">Melt</span> Lakes in Greenland</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>J. Adler; K. Steffen</p> <p>2007-01-01</p> <p>The objective of this August 2007 week-long test campaign was to assess the viability of supraglacial lake depths with high-resolution hyperspectral measurements. The knowledge of <span class="hlt">melt</span> lake depth is essential in determining the volume of water which forms on top of glacial surfaces during the annual <span class="hlt">melt</span> season. The assessment of <span class="hlt">melt</span> water volume is a crucial input parameter for</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://www.agu.org/journals/jb/v083/iB06/JB083iB06p02737/JB083iB06p02737.pdf"><span id="translatedtitle">MANICOUAGAN IMPACT <span class="hlt">MELT</span>, QUEBEC, 1, STRATIGRAPHY, PETROLOGY, AND CHEMISTRY</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>R. J. Floran; R. A. F. Grieve; W. C. Phinney; J. L. Warner; C. H. Simonds; D. P. Blanchard; M. R. Dence</p> <p>1978-01-01</p> <p>Within the moderately eroded Mani- couagan structure a sheet of clast-laden impact <span class="hlt">melt</span> 230 m thick and 55 km in diameter forms an annular plateau surrounding an uplift of shocked anorthosite. The <span class="hlt">melt</span> sheet is divided into three vertically gradational units based on de- creasing clast abundance and coarsening of the <span class="hlt">melt</span> above the base. A very fine-grained lower unit,</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/53270134"><span id="translatedtitle">Near-wall behavior of polymer <span class="hlt">melts</span> in shear flow</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Geoffrey Marc Wise</p> <p>1999-01-01</p> <p>Attenuated total reflectance (ATR) spectroscopy was used to investigate the near-surface dynamics of polymer <span class="hlt">melts</span> under flow conditions for three different systems: weak flow of model lubricants, mild flow of polybutadiene <span class="hlt">melts</span>, and strong flow of polybutadiene <span class="hlt">melts</span>. Most experiments were conducted on a zinc selenide surface, which was shown to be nonattractive for the materials under study. In addition,</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=USGSPUBS&redirectUrl=http://pubs.er.usgs.gov/publication/70028079"><span id="translatedtitle">Confirmation of a meteoritic component in impact-<span class="hlt">melt</span> rocks of the Chesapeake Bay impact structure, Virginia, USA - Evidence from osmium isotopic and PGE systematics</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Lee, S.R.; Horton, J.W., Jr.; Walker, R.J.</p> <p>2006-01-01</p> <p>The osmium isotope ratios and platinum-group element (PGE) concentrations of impact-<span class="hlt">melt</span> rocks in the Chesapeake Bay impact structure were determined. The impact-<span class="hlt">melt</span> rocks come from the <span class="hlt">cored</span> part of a lower-crater section of suevitic crystalline-clast breccia in an 823 m scientific test hole over the central uplift at Cape Charles, Virginia. The 187Os/188Os ratios of impact-<span class="hlt">melt</span> rocks range from 0.151 to 0.518. The rhenium and platinum-group element (PGE) concentrations of these rocks are 30-270?? higher than concentrations in basement gneiss, and together with the osmium isotopes indicate a substantial meteoritic component in some impact-<span class="hlt">melt</span> rocks. Because the PGE abundances in the impact-<span class="hlt">melt</span> rocks are dominated by the target materials, interelemental ratios of the impact-<span class="hlt">melt</span> rocks are highly variable and nonchondritic. The chemical nature of the projectile for the Chesapeake Bay impact structure cannot be constrained at this time. Model mixing calculations between chondritic and crustal components suggest that most impact-<span class="hlt">melt</span> rocks include a bulk meteoritic component of 0.01-0.1% by mass. Several impact-<span class="hlt">melt</span> rocks with lowest initial 187Os/188Os ratios and the highest osmium concentrations could have been produced by additions of 0.1%-0.2% of a meteoritic component. In these samples, as much as 70% of the total Os may be of meteoritic origin. At the calculated proportions of a meteoritic component (0.01-0.1% by mass), no mixtures of the investigated target rocks and sediments can reproduce the observed PGE abundances of the impact-<span class="hlt">melt</span> rocks, suggesting that other PGE enrichment processes operated along with the meteoritic contamination. Possible explanations are 1) participation of unsampled target materials with high PGE abundances in the impact-<span class="hlt">melt</span> rocks, and 2) variable fractionations of PGE during syn- to post-impact events. ?? The Meteoritical Society, 2006.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2004AGUFMMR41A..09A"><span id="translatedtitle">Timing And Processes Of Earth's <span class="hlt">Core</span> Differentiation.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allegre, C. J.; Manhes, G.; Gopel, C.</p> <p>2004-12-01</p> <p>Small 182W abundance excess of terrestrial W relative to W in bulk chondrites has been recently established (Yin et al. 2002, Kleine et al. 2002, Schoenberg et al. 2002). Rapid terrestrial accretion and early <span class="hlt">core</span> formation, with completion of the bulk metal-silicate separation within less than 30 Myr have been proposed on this basis. These studies underline how much this 182W/182Hf time scale agrees with dynamic accretion models (Wetherill, 1986) that predict a ˜10 Myr interval for the main growth stage of Earth's formation. This W model time scale for terrestrial accretion is shorter than current estimates based on Pb isotope systematics of mantle-derived basalts and terrestrial Xe isotope systematics. The end of metal-silicate differentiation and large scale mantle degassing has been defined ˜100 My after beginning of the accretion. These studies also indicate agreement of this time scale with dynamic accretion models that predict 100 My for the end of Earth's accretion. The Hf-W time scale for accretion and <span class="hlt">core</span> formation assumes total equilibration of incoming metal and silicate of impactors with the bulk silicate Earth (BSE) during planet's growth. Recently, the assumption of incomplete equilibration of metal and silicate components with BSE has been investigated (Halliday, 2004). It is proposed that impacting <span class="hlt">core</span> material has not always efficiently mixed with the silicate portions of the Earth before being added to the Earth's <span class="hlt">core</span> Our approach also considers that equilibration between metal and silicate has not been complete in BSE during Earth's growth, and we argue that early part of the Earth's <span class="hlt">core</span> has segregated through unmelted silicate material. When the baby Earth was large enough, the increase of the temperature induced Fe-FeS eutectic <span class="hlt">melting</span>. The liquid metal segregated through the crystalline silicate matrix and formed the early part of the Earth's <span class="hlt">core</span>. Experimental study (Yoshino et al. 2003) indicates the percolation threshold for molten iron-sulphur compounds of 5 vol% solid olivine, through channel on triple junction between minerals. This study allows us to reconsider the precedent proposition (Stevenson, 1990) based on experimental and theoretical considerations suggesting that percolation of metallic iron rich liquid through a mostly solid silicate matrix is largely prevented because of the high surface tension of iron. During formation and segregation of the Fe-FeS eutectic, W isotopic equilibration is limited by the diffusion through the solid silicate matrix. During the further Earth's growth, impact <span class="hlt">melting</span> increased and has induced a progressive <span class="hlt">melting</span> of BSE up to the formation of magma ocean at the end of the planet's accretion. Before the occurrence of the magma ocean, W equilibration between impactors and BSE has not been complete This incomplete isotopic exchange between terrestrial metal and metal originating from impactors with solid part of BSE during early accretion of the Earth leads to the observed excess of 182W of present BSE. It occurs when the 182W production in BSE is most significant, due to the short half-life of 182Hf. The change of segregation mechanisms of Earth's <span class="hlt">core</span> during planet's growth and short-sightedness of Hf-W chronometer focused to the early segregation of Earth's <span class="hlt">core</span> make the divergence with the U-Pb and I-Xe terrestrial records. Yin et al. 2002, Nature 418, 949-952. Kleine et al. 2002, Nature 418, 952-955. Schoenberg et al. 2002, Geochim. Cosmochim. Acta 66, 3151-3160. Wetherill 1986, in Origin of the Moon, eds Hartmann et al., LPI, 519-550. Yoshino et al. 2003, Nature 422, 154-157. Stevenson 1990, in Origin of the Earth, eds Newson et al., LPI, 231-249.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014AGUFM.V24D..03A"><span id="translatedtitle">Composition of Crustal <span class="hlt">Melts</span> at the Source Area: Information from Glassy <span class="hlt">Melt</span> Inclusions in Anatectic Enclaves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Acosta-vigil, A.; Cesare, B.; London, D.; Morgan, G. B., VI; Buick, I.; Hermann, J.; Bartoli, O.; Remusat, L.</p> <p>2014-12-01</p> <p>Crustal anatexis, together with <span class="hlt">melt</span> extraction and ascent to upper crustal levels, generate plutons and volcanic edifices of granitoid composition. This process constitutes the main mechanism for the differentiation of the continental crust. A recent breakthrough in the study of crustal anatexis is the discovery of former <span class="hlt">melt</span> inclusions in peritectic minerals of anatectic rocks. These <span class="hlt">melt</span> droplets show now as glassy inclusions in rapidly cooled anatectic enclaves within volcanic rocks, or as polycrystalline aggregates (nanogranites) in migmatites. Analysis of glassy inclusions and of rehomogenized nanogranites provide direct information on the composition of crustal <span class="hlt">melts</span> at the source of crustal magmas, on the extent of equilibration between <span class="hlt">melt</span> and residue, and on the fluid regime during anatexis. A comprehensive geochemical study (?350 EMP, 100 LA-ICPMS and 80 nanoSIMS analyses) of matrix glasses and glassy <span class="hlt">melt</span> inclusions in Pl and Grt of anatectic enclaves within El Hoyazo dacite (Betic Cordillera, S Spain), recording <span class="hlt">melt</span> compositions during regional anatexis at ?700-850 ºC and 0.5-0.7 GPa, shows that <span class="hlt">melts</span> are leucogranitic (FeOt+MgO+TiO2=1.0-2.0 wt%), moderately to strongly peraluminous (ASI=1.10-1.25), with H2O concentrations well below saturation (3-5 wt%). They are heterogeneous and spread around the 0.5-0.7 GPa haplogranite H2O-undersaturated eutectics. Glassy inclusions in Pl are more heterogeneous, richer in normative Qtz and H2O, and poorer in FeOt and CaO compared to glassy inclusions in Grt and matrix glass. All glasses have moderate to high concentrations of LILE and low to very low concentrations in FRTE, HFSE and REE. Glass inclusions in Pl and Grt have higher concentrations of LILE, lower concentrations of Y, Zr, REE, and lower values of Th/U compared to matrix glasses. Surprisingly, and in spite of the compositional heterogeneity, glasses are at or close to equilibrium with their residue regarding most of the trace elements, except for some degree of undersaturation in accessory minerals Zrn and Mnz. The compositions of glassy inclusions in Pl and Grt and matrix glasses are interpreted to record the compositional evolution of <span class="hlt">melt</span> during the prograde <span class="hlt">melting</span> of the enclaves from ?700 to 800-850 ºC.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/811812"><span id="translatedtitle">HYDRATE <span class="hlt">CORE</span> DRILLING TESTS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>John H. Cohen; Thomas E. Williams; Ali G. Kadaster; Bill V. Liddell</p> <p>2002-11-01</p> <p>The ''Methane Hydrate Production from Alaskan Permafrost'' project is a three-year endeavor being conducted by Maurer Technology Inc. (MTI), Noble, and Anadarko Petroleum, in partnership with the U.S. DOE National Energy Technology Laboratory (NETL). The project's goal is to build on previous and ongoing R&D in the area of onshore hydrate deposition. The project team plans to design and implement a program to safely and economically drill, <span class="hlt">core</span> and produce gas from arctic hydrates. The current work scope includes drilling and <span class="hlt">coring</span> one well on Anadarko leases in FY 2003 during the winter drilling season. A specially built on-site <span class="hlt">core</span> analysis laboratory will be used to determine some of the physical characteristics of the hydrates and surrounding rock. Prior to going to the field, the project team designed and conducted a controlled series of <span class="hlt">coring</span> tests for simulating <span class="hlt">coring</span> of hydrate formations. A variety of equipment and procedures were tested and modified to develop a practical solution for this special application. This Topical Report summarizes these <span class="hlt">coring</span> tests. A special facility was designed and installed at MTI's Drilling Research Center (DRC) in Houston and used to conduct <span class="hlt">coring</span> tests. Equipment and procedures were tested by cutting <span class="hlt">cores</span> from frozen mixtures of sand and water supported by casing and designed to simulate hydrate formations. Tests were conducted with chilled drilling fluids. Tests showed that frozen <span class="hlt">core</span> can be washed out and reduced in size by the action of the drilling fluid. Washing of the <span class="hlt">core</span> by the drilling fluid caused a reduction in <span class="hlt">core</span> diameter, making <span class="hlt">core</span> recovery very difficult (if not impossible). One successful solution was to drill the last 6 inches of <span class="hlt">core</span> dry (without fluid circulation). These tests demonstrated that it will be difficult to capture <span class="hlt">core</span> when drilling in permafrost or hydrates without implementing certain safeguards. Among the <span class="hlt">coring</span> tests was a simulated hydrate formation comprised of coarse, large-grain sand in ice. Results with this <span class="hlt">core</span> showed that the viscosity of the drilling fluid must also be carefully controlled. When coarse sand was being <span class="hlt">cored</span>, the <span class="hlt">core</span> barrel became stuck because the drilling fluid was not viscous enough to completely remove the large grains of sand. These tests were very valuable to the project by showing the difficulties in <span class="hlt">coring</span> permafrost or hydrates in a laboratory environment (as opposed to a field environment where drilling costs are much higher and the potential loss of equipment greater). Among the conclusions reached from these simulated hydrate <span class="hlt">coring</span> tests are the following: Frozen hydrate <span class="hlt">core</span> samples can be recovered successfully; A spring-finger <span class="hlt">core</span> catcher works best for catching hydrate <span class="hlt">cores</span>; Drilling fluid can erode the <span class="hlt">core</span> and reduces its diameter, making it more difficult to capture the <span class="hlt">core</span>; Mud must be designed with proper viscosity to lift larger cuttings; and The bottom 6 inches of <span class="hlt">core</span> may need to be drilled dry to capture the <span class="hlt">core</span> successfully.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=CFR&redirectUrl=http://www.gpo.gov:80/fdsys/pkg/CFR-2010-title7-vol3/pdf/CFR-2010-title7-vol3-sec58-318.pdf"><span id="translatedtitle">7 CFR 58.318 - Butter, frozen or plastic cream <span class="hlt">melting</span> machines.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-01-01</p> <p>... Butter, frozen or plastic cream <span class="hlt">melting</span> machines. 58.318 Section 58.318 Agriculture... Butter, frozen or plastic cream <span class="hlt">melting</span> machines. Shavers, shredders or <span class="hlt">melting</span> machines used for rapid <span class="hlt">melting</span> of butter, frozen...</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=CFR2011&redirectUrl=http://www.gpo.gov:80/fdsys/pkg/CFR-2011-title7-vol3/pdf/CFR-2011-title7-vol3-sec58-318.pdf"><span id="translatedtitle">7 CFR 58.318 - Butter, frozen or plastic cream <span class="hlt">melting</span> machines.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-01-01</p> <p>... Butter, frozen or plastic cream <span class="hlt">melting</span> machines. 58.318 Section 58.318 Agriculture... Butter, frozen or plastic cream <span class="hlt">melting</span> machines. Shavers, shredders or <span class="hlt">melting</span> machines used for rapid <span class="hlt">melting</span> of butter, frozen...</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PMC&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3198344"><span id="translatedtitle">Evidence of denser MgSiO3 glass above 133 gigapascal (GPa) and implications for remnants of ultradense silicate <span class="hlt">melt</span> from a deep magma ocean</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Murakami, Motohiko; Bass, Jay D.</p> <p>2011-01-01</p> <p>Ultralow velocity zones are the largest seismic anomalies in the mantle, with 10–30% seismic velocity reduction observed in thin layers less than 20–40 km thick, just above the Earth’s <span class="hlt">core</span>-mantle boundary (CMB). The presence of silicate <span class="hlt">melts</span>, possibly a remnant of a deep magma ocean in the early Earth, have been proposed to explain ultralow velocity zones. It is, however, still an open question as to whether such silicate <span class="hlt">melts</span> are gravitationally stable at the pressure conditions above the CMB. Fe enrichment is usually invoked to explain why <span class="hlt">melts</span> would remain at the CMB, but this has not been substantiated experimentally. Here we report in situ high-pressure acoustic velocity measurements that suggest a new transformation to a denser structure of MgSiO3 glass at pressures close to those of the CMB. The result suggests that MgSiO3 <span class="hlt">melt</span> is likely to become denser than crystalline MgSiO3 above the CMB. The presence of negatively buoyant and gravitationally stable silicate <span class="hlt">melts</span> at the bottom of the mantle, would provide a mechanism for observed ultralow seismic velocities above the CMB without enrichment of Fe in the <span class="hlt">melt</span>. An ultradense <span class="hlt">melt</span> phase and its geochemical inventory would be isolated from overlying convective flow over geologic time. PMID:21969547</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://presolar.wustl.edu/Laboratory_for_Space_Sciences/CF_Publications_files/1998_Indarch.pdf"><span id="translatedtitle">SULFIDE/SILICATE <span class="hlt">MELT</span> PARTITIONING DURING ENSTATITE CHONDRITE <span class="hlt">MELTING</span>. C. Floss1 R.A. Fogel2</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p></p> <p></p> <p>SULFIDE/SILICATE <span class="hlt">MELT</span> PARTITIONING DURING ENSTATITE CHONDRITE <span class="hlt">MELTING</span>. C. Floss1 , R.A. Fogel2 , G their origin remains poorly understood, at least partly because of confusion over the role played by sulfides between sulfides and silicates during <span class="hlt">melting</span> of natural enstatite chondrite material. Results: Powdered</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/436274"><span id="translatedtitle">Precipitation of metal nitrides from chloride <span class="hlt">melts</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Slater, S.A.; Miller, W.E.; Willit, J.L.</p> <p>1996-12-31</p> <p>Precipitation of actinides, lanthanides, and fission products as nitrides from molten chloride <span class="hlt">melts</span> is being investigated for use as a final cleanup step in treating radioactive salt wastes generated by electrometallurgical processing of spent nuclear fuel. The radioactive components (eg, fission products) need to be removed to reduce the volume of high-level waste that requires disposal. To extract the fission products from the salt, a nitride precipitation process is being developed. The salt waste is first contacted with a molten metal; after equilibrium is reached, a nitride is added to the metal phase. The insoluble nitrides can be recovered and converted to a borosilicate glass after air oxidation. For a bench-scale experimental setup, a crucible was designed to contact the salt and metal phases. Solubility tests were performed with candidate nitrides and metal nitrides for which there are no solubility data. Experiments were performed to assess feasibility of precipitation of metal nitrides from chloride <span class="hlt">melts</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/25279643"><span id="translatedtitle">Specific heat in two-dimensional <span class="hlt">melting</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Deutschländer, Sven; Puertas, Antonio M; Maret, Georg; Keim, Peter</p> <p>2014-09-19</p> <p>We report the specific heat cN around the <span class="hlt">melting</span> transition(s) of micrometer-sized superparamagnetic particles confined in two dimensions, calculated from fluctuations of positions and internal energy, and corresponding Monte Carlo simulations. Since colloidal systems provide single particle resolution, they offer the unique possibility to compare the experimental temperatures of the peak position of cN(T) and symmetry breaking, respectively. While order parameter correlation functions confirm the Kosterlitz-Thouless-Halperin-Nelson-Young <span class="hlt">melting</span> scenario where translational and orientational order symmetries are broken at different temperatures with an intermediate so called hexatic phase, we observe a single peak of the specific heat within the hexatic phase, with excellent agreement between experiment and simulation. Thus, the peak is not associated with broken symmetries but can be explained with the total defect density, which correlates with the maximum increase of isolated dislocations. The absence of a latent heat strongly supports the continuous character of both transitions. PMID:25279643</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19920074686&hterms=floating&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dfloating"><span id="translatedtitle">Floating zone <span class="hlt">melting</span> of cadmium telluride</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chang, Wen-Ming; Regel, L. L.; Wilcox, W. R.</p> <p>1992-01-01</p> <p>To produce superior crystals of cadmium telluride, floating zone <span class="hlt">melting</span> in space has been proposed. Techniques required for floating zone <span class="hlt">melting</span> of cadmium telluride are being developed. We have successfully float-zoned cadmium telluride on earth using square rods. A resistance heater was constructed for forming the molten zone. Evaporation of the molten zone was controlled by adding excess cadmium to the growth ampoule combined with heating of the entire ampoule. An effective method to hold the feed rod was developed. Slow rotation of the growth ampoule was proven experimentally to be necessary to achieve a complete symmetric molten zone. Most of the resultant cylindrical rods were single crystals with twins. Still needed is a suitable automatic method to control the zone length. We tried a fiber optical technique to control the zone length, but experiments showed that application of this technique to automate zone length control is unlikely to be successful.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=DOE-PATENT-XML&redirectUrl=http://www.osti.gov/doepatents/biblio/867766"><span id="translatedtitle">Thermally efficient <span class="hlt">melting</span> for glass making</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Chen, Michael S. K. (Zionsville, PA); Painter, Corning F. (Allentown, PA); Pastore, Steven P. (Allentown, PA); Roth, Gary (Trexlertown, PA); Winchester, David C. (Allentown, PA)</p> <p>1991-01-01</p> <p>The present invention is an integrated process for the production of glass utilizing combustion heat to <span class="hlt">melt</span> glassmaking materials in a glassmaking furnace. The fuel combusted to produce heat sufficient to <span class="hlt">melt</span> the glassmaking materials is combusted with oxygen-enriched oxidant to reduce heat losses from the offgas of the glassmaking furnace. The process further reduces heat losses by quenching hot offgas from the glassmaking furnace with a process stream to retain the heat recovered from quench in the glassmaking process with subsequent additional heat recovery by heat exchange of the fuel to the glassmaking furnace, as well as the glassmaking materials, such as batch and cullet. The process includes recovery of a commercially pure carbon dioxide product by separatory means from the cooled, residual offgas from the glassmaking furnace.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2012JChPh.136v4906Z"><span id="translatedtitle">Simulation of <span class="hlt">melting</span> in crystalline polyethylene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zubova, E. A.; Balabaev, N. K.; Musienko, A. I.; Gusarova, E. B.; Mazo, M. A.; Manevitch, L. I.; Berlin, A. A.</p> <p>2012-06-01</p> <p>We carry out a molecular dynamics simulation of the first stages of constrained <span class="hlt">melting</span> in crystalline polyethylene (PE). When heated, the crystal undergoes two structural phase transitions: from the orthorhombic (O) phase to the monoclinic (M) phase, and then to the columnar (C), quasi-hexagonal, phase. The M phase represents the tendency to the parallel packing of planes of PE zigzags, and the C phase proves to be some kind of oriented <span class="hlt">melt</span>. We follow both the transitions O?M and M?C in real time and establish that, at their beginning, the crystal tries (and fails) to pass into the partially ordered phases similar to the RI and RII phases of linear alkanes, correspondingly. We discuss the molecular mechanisms and driving forces of the observed transitions, as well as the reasons why the M and C phases in PE crystals substitute for the rotator phases in linear alkanes.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/40849560"><span id="translatedtitle">Causes and consequences of protracted <span class="hlt">melting</span> of the mid-crust exposed in the North Himalayan antiform</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Hongfei Zhang; Nigel Harris; Randy Parrish; Simon Kelley; Li Zhang; Nick Rogers; Tom Argles; Jess King</p> <p>2004-01-01</p> <p>Gneiss domes exposed by the North Himalayan antiform in southern Tibet provide evidence for protracted <span class="hlt">melting</span> of the mid-crust during convergent tectonics. Anatexis was initiated during underthrusting and recurred during the southwards extrusion of a low-viscosity crustal sheet. Sr–Nd isotope systematics establish that the <span class="hlt">cores</span> of the domes, dominated by Cambrian gneiss, form a window of the High Himalayan Crystalline</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/18496260"><span id="translatedtitle">High index-contrast all-solid photonic crystal fibers by pressure-assisted <span class="hlt">melt</span> infiltration of silica matrices</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Ning da; Lothar Wondraczek; Markus A. Schmidt; Nicolai Granzow; Philip St. J. Russell</p> <p>2010-01-01</p> <p>All-solid photonic crystal fibers (PCFs) are created by pressure-assisted filling of low-<span class="hlt">melting</span>-point chalcogenide and tellurite glasses into silica matrix fibers with channel diameters as small as 200nm. Overcoming to a large extent the problem of viscosity and, thus, process incompatibility of silica and non-silicate optical glasses, the technique provides a unique way of producing waveguiding devices with high <span class="hlt">core</span>-cladding index-contrast,</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PMC&redirectUrl=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3908934"><span id="translatedtitle">Bacterial Communities of Surface Mixed Layer in the Pacific Sector of the Western Arctic Ocean during Sea-Ice <span class="hlt">Melting</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ha, Ho Kyung; Kim, Hyun Cheol; Kim, Ok-Sun; Lee, Bang Yong; Cho, Jang-Cheon; Hur, Hor-Gil; Lee, Yoo Kyung</p> <p>2014-01-01</p> <p>From July to August 2010, the IBRV ARAON journeyed to the Pacific sector of the Arctic Ocean to monitor bacterial variation in Arctic summer surface-waters, and temperature, salinity, fluorescence, and nutrient concentrations were determined during the ice-<span class="hlt">melting</span> season. Among the measured physicochemical parameters, we observed a strong negative correlation between temperature and salinity, and consequently hypothesized that the <span class="hlt">melting</span> ice decreased water salinity. The bacterial community compositions of 15 samples, includicng seawater, sea-ice, and <span class="hlt">melting</span> pond water, were determined using a pyrosequencing approach and were categorized into three habitats: (1) surface seawater, (2) ice <span class="hlt">core</span>, and (3) <span class="hlt">melting</span> pond. Analysis of these samples indicated the presence of local bacterial communities; a deduction that was further corroborated by the discovery of seawater- and ice-specific bacterial phylotypes. In all samples, the Alphaproteobacteria, Flavobacteria, and Gammaproteobacteria taxa composed the majority of the bacterial communities. Among these, Alphaproteobacteria was the most abundant and present in all samples, and its variation differed among the habitats studied. Linear regression analysis suggested that changes in salinity could affect the relative proportion of Alphaproteobacteria in the surface water. In addition, the species-sorting model was applied to evaluate the population dynamics and environmental heterogeneity in the bacterial communities of surface mixed layer in the Arctic Ocean during sea-ice <span class="hlt">melting</span>. PMID:24497990</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/1007587"><span id="translatedtitle">Partial <span class="hlt">melting</span> in the iron?sulfur system at high pressure: A synchrotron X-ray diffraction study</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Campbell, A.J.; Seagle, C.T.; Heinz, D.L.; Shen, G.; Prakapenka, V. (Maryland); (CIW); (UC)</p> <p>2008-09-18</p> <p>Partial <span class="hlt">melting</span> in the Fe-S system was investigated at high pressures because of its importance to understanding the formation, composition, and thermal structure of the Earth's <span class="hlt">core</span>. Earlier studies at very high pressure (>25 GPa) took place before the discovery of Fe{sub 3}, which compromised the interpretation of those results. Furthermore, they relied on textural criteria for <span class="hlt">melting</span> that are difficult to apply at high pressure. In this study synchrotron X-ray diffraction was used to monitor coexisting metal and sulfide at high pressures and temperatures, during laser heating in a diamond anvil cell. The criterion for <span class="hlt">melting</span> was the disappearance of one of the two coexisting phases, and reappearance upon quench. Temperatures of eutectic <span class="hlt">melting</span> between Fe and Fe{sub 3}S were bracketed in this way up to 60 GPa, and a lower bound was established at 80 GPa. The accuracy of the <span class="hlt">melting</span> point measured in these studies was improved through modelling of the axial temperature distribution through the thickness of the sample; this indicated an {approx}6% correction to the spectroradiometrically determined temperature. The Fe-Fe{sub 3}S eutectic composition remains close to 15 wt% S up to 60 GPa.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://ntrs.nasa.gov/search.jsp?R=19740043064&hterms=elemental+carbon&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Delemental%2Bcarbon"><span id="translatedtitle">Vacuum arc <span class="hlt">melting</span> of tungsten-hafnium-carbon alloy</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ammon, R. L.; Buckman, R. W., Jr.</p> <p>1974-01-01</p> <p>The vacuum arc casting of tungsten alloys, which contain carbon as an alloy addition, require special <span class="hlt">melting</span> procedures in order to produce <span class="hlt">melts</span> of consistent controlled levels of alloy content. A <span class="hlt">melting</span> procedure will be described in which elemental components of a tungsten 0.35% HfC alloy are assembled to form an electrode for ac vacuum arc <span class="hlt">melting</span> to produce 3-in.-diam ingots. <span class="hlt">Melting</span> procedures and analytical chemistry are discussed and compared with data for ingots produced by other techniques.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/servlets/purl/251368"><span id="translatedtitle">Exo-<span class="hlt">Melt</span>{trademark} process for intermetallic powders</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sikka, V.K. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.; Deevi, S.C. [Philip Morris U.S.A., Richmond, VA (United States). Research Center</p> <p>1996-06-01</p> <p>The methods of powder production for intermetallics are reviewed. An innovative method known as Exo-<span class="hlt">Melt</span>{trademark} is described for producing molten aluminides for gas- and water-atomization processes that require a molten metal stream. The Exo-<span class="hlt">Melt</span>{trademark} process is based on the effective utilization of the heats of formation of aluminides from their constituent elements. The Exo-<span class="hlt">Melt</span>{trademark} process principles are discussed along with a description of a furnace-loading sequence that uses the principles for practical applications. The benefits of the Exo-<span class="hlt">Melt</span>{trademark} process are compared with the problems associated with the conventional <span class="hlt">melting</span> process.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1503.00964v1"><span id="translatedtitle">Lattice Monte Carlo Simulations of Polymer <span class="hlt">Melts</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Hsiao-Ping Hsu</p> <p>2015-03-03</p> <p>We use Monte Carlo simulations to study polymer <span class="hlt">melts</span> consisting of fully flexible and moderately stiff chains in the bond fluctuation model at a volume fraction $0.5$. In order to reduce the local density fluctuations, we test a pre-packing process for the preparation of the initial configurations of the polymer <span class="hlt">melts</span>, before the excluded volume interaction is switched on completely. This process leads to a significantly faster decrease of the number of overlapping monomers on the lattice. This is useful for simulating very large systems, where the statistical properties of the model with a marginally incomplete elimination of excluded volume violations are the same as those of the model with strictly excluded volume. We find that the internal mean square end-to-end distance for moderately stiff chains in a <span class="hlt">melt</span> can be very well described by a freely rotating chain model with a precise estimate of the bond-bond orientational correlation between two successive bond vectors in equilibrium. The plot of the probability distributions of the reduced end-to-end distance of chains of different stiffness also shows that the data collapse is excellent and described very well by the Gaussian distribution for ideal chains. However, while our results confirm the systematic deviations between Gaussian statistics for the chain structure factor $S_c(q)$ [minimum in the Kratky-plot] found by Wittmer et al.~\\{EPL {\\bf 77} 56003 (2007).\\} for fully flexible chains in a <span class="hlt">melt</span>, we show that for the available chain length these deviations are no longer visible, when the chain stiffness is included. The mean square bond length and the compressibility estimated from collective structure factors depend slightly on the stiffness of the chains.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NSDL&redirectUrl=http://www.andrill.org/flexhibit/flexhibit/materials/activities/Activity5B-WhatIfTheIceShelvesMelted.pdf"><span id="translatedtitle">What if the Ice Shelves <span class="hlt">Melted</span>?</span></a></p> <p><a target="_blank" href="http://nsdl.org/nsdl_dds/services/ddsws1-1/service_explorer.jsp">NSDL National Science Digital Library</a></p> <p>LuAnn Dahlman</p> <p></p> <p>This activity is a hands-on guided inquiry activity designed to highlight the role of an ice shelf on slowing the movement of continental ice sheets in Antarctica. Students build a model of Antarctica and both continental glaciers and ice shelves using paper models of the land and slime for glaciers and ice. Students use their model to explore the impact of recent and potential ice shelf <span class="hlt">melting</span> and break-up.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2015EGUGA..17.5905Y"><span id="translatedtitle">Quantifying crystal-<span class="hlt">melt</span> segregation in dykes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamato, Philippe; Duretz, Thibault; May, Dave A.; Tartèse, Romain</p> <p>2015-04-01</p> <p>The dynamics of magma flow is highly affected by the presence of a crystalline load. During magma ascent, it has been demonstrated that crystal-<span class="hlt">melt</span> segregation constitutes a viable mechanism for magmatic differentiation. However, the influences of crystal volume fraction, geometry, size and density on crystal <span class="hlt">melt</span> segregation are still not well constrained. In order to address these issues, we performed a parametric study using 2D direct numerical simulations, which model the ascension of crystal-bearing magma in a vertical dyke. Using these models, we have characterised the amount of segregation as a function of different quantities including: the crystal fraction (?), the density contrast between crystals and <span class="hlt">melt</span> (??), the size of the crystals (Ac) and their aspect ratio (R). Results show that crystal aspect ratio does not affect the segregation if R is small enough (long axis smaller than ~1/6 of the dyke width, Wd). Inertia within the system was also found not to influence crystal-<span class="hlt">melt</span> segregation. The degree of segregation was however found to be highly dependent upon other parameters. Segregation is highest when ?? and Ac are large, and lowest for large pressure gradient (Pd) and/or large values of Wd. These four parameters can be combined into a single one, the Snumber, which can be used to quantify the segregation. Based on systematic numerical modelling and dimensional analysis, we provide a first order scaling law which allows quantification of the segregation for an arbitrary Snumber and ?, encompassing a wide range of typical parameters encountered in terrestrial magmatic systems.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=DOE-PATENT-XML&redirectUrl=http://www.osti.gov/doepatents/biblio/1014939"><span id="translatedtitle">Low-<span class="hlt">melting</span> point heat transfer fluid</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Cordaro, Joseph Gabriel (Oakland, CA); Bradshaw, Robert W. (Livermore, CA)</p> <p>2010-11-09</p> <p>A low-<span class="hlt">melting</span> point, heat transfer fluid made of a mixture of five inorganic salts including about 29.1-33.5 mol % LiNO.sub.3, 0-3.9 mol % NaNO.sub.3, 2.4-8.2 mol % KNO.sub.3, 18.6-19.9 mol % NaNO.sub.2, and 40-45.6 mol % KNO.sub.2. These compositions can have liquidus temperatures below 80.degree. C. for some compositions.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1994PhyC..235..455U"><span id="translatedtitle">Characterization of VGF <span class="hlt">melt</span>-grown YBCO</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ullrich, M.; Freyhardt, H. C.</p> <p>1994-12-01</p> <p>In <span class="hlt">melt</span>-textured Y?Ba?Cu?O (YBCO), prepared by the vertical gradient freeze (VGF) technique, the influence of a significantly larger cooling rate through the peritectic reaction was investigated. A three times faster cooling rate results mainly in a larger amount of cracks and in a size reduction of the textured domains. As in the case of smaller cooling rates, however, the c-axis is found to be almost parallel to the external temperature gradient.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1501.06981.pdf"><span id="translatedtitle">Regelation: why does ice <span class="hlt">melt</span> under pressure?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Sun, Chang Q</p> <p>2015-01-01</p> <p>Unlike other unusual materials whose bonds contract under compression, the O:H nonbond undergoes contraction and the H-O bond elongation towards O:H and H-O length symmetry in water and ice. The energy drop of the H-O bond dictates the <span class="hlt">melting</span> point Tm depression of ice. Once the pressure is relieved, the O:H-O bond fully recovers its initial state, resulting in Regelation.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1501.06981v1"><span id="translatedtitle">Regelation: why does ice <span class="hlt">melt</span> under pressure?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Chang Q Sun</p> <p>2015-01-28</p> <p>Unlike other unusual materials whose bonds contract under compression, the O:H nonbond undergoes contraction and the H-O bond elongation towards O:H and H-O length symmetry in water and ice. The energy drop of the H-O bond dictates the <span class="hlt">melting</span> point Tm depression of ice. Once the pressure is relieved, the O:H-O bond fully recovers its initial state, resulting in Regelation.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-STC&redirectUrl=http://www.osti.gov/scitech/biblio/899666"><span id="translatedtitle">Scale modeling of aluminum <span class="hlt">melting</span> furnaces</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Penmetsa, S.S. (Dept. of Mechanical Engineering, Univ. of Kentucky Lexington, KY); Li, T. (Dept. of Mechanical Engineering, Univ. of Kentucky Lexington, KY); King, Paul E.; Saito, K. (Dept. of Mechanical Engineering, Univ. of Kentucky Lexington, KY)</p> <p>2005-02-01</p> <p>Improving energy efficiency in secondary aluminum <span class="hlt">melting</span>, done in large rectangular or round-top reverberatory furnaces, has been one of the major interests to the aluminum industry. To assist the industries in improving energy efficiency in aluminum <span class="hlt">melting</span>, an experimental research furnace (ERF) with 907 kg capacity has been built at the Albany Research Center of the U.S. Department of Energy as part of this multi-partner research program. To verify that the results from experiments conducted in the ERF furnace is validate for the operations of industrial furnaces, we use scale modeling technology to assist the validation. In this paper we present the results from our experiments in the model furnace, which was scale-down from the ERF furnace (as a prototype), and then compare them to the tests on the ERF furnace. The scaling laws which are applied to the thermal conduction loss through the walls of the model furnace were first developed, and the partial modeling relaxation technique was applied in the development of modeling to derive achievable scaling laws. Temperature distributions across the model furnace walls were measured and found to compare with the prototype favorably. Good agreement between the results obtained from the model experiments and from the ERF tests demonstrate that the scale modeling is expected to be a useful tool because the physical behavior of <span class="hlt">melting</span> phenomena in the industrial furnaces can be explored by conducting experiments in a small, scaled-down furnace, and can be applied in the study of improving energy efficiency in aluminum <span class="hlt">melting</span>.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/14875246"><span id="translatedtitle">Relationship between <span class="hlt">melting</span> and amorphization of ice</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Osamu Mishima</p> <p>1996-01-01</p> <p>THE discovery1 in 1984 that an ice crystal can be transformed by pressure to an amorphous phase has since been followed by other examples of pressure-induced amorphization2. This transition, like <span class="hlt">melting</span>, involves loss of long-ranged order, prompting the question of whether the two transitions are related. Here I describe experiments probing this relationship for a form of crystalline ice (denoted</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=EPRINT&redirectUrl=http://arxiv.org/pdf/1507.02305.pdf"><span id="translatedtitle">Topological Constraints in Directed Polymer <span class="hlt">Melts</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/eprints/">E-print Network</a></p> <p>Serna, Pablo; Nahum, Adam</p> <p>2015-01-01</p> <p>Polymers in a <span class="hlt">melt</span> may be subject to topological constraints, as in the example of unlinked polymer rings. How to do statistical mechanics in the presence of such constraints remains a fundamental open problem. We study the effect of topological constraints on a <span class="hlt">melt</span> of directed polymers using simulations of a simple quasi-2D model. We find that fixing the global topology of the <span class="hlt">melt</span> to be trivial changes the polymer conformations drastically. Polymers of length $L$ wander in the transverse direction only by a distance of order $(\\ln L)^\\zeta$ with $\\zeta \\simeq 1.5$. This is strongly suppressed in comparison with the Brownian scaling $L^{1/2}$ which holds in the absence of the topological constraint. It is also much less than the prediction $L^{1/4}$ of a mean-field-like `array of obstacles' model: thus we rule out such a model in the present setting. Dynamics are also strongly affected by the constraints, and a tagged monomer in an infinite system performs logarithmically slow subdiffusion. To cast light on...</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2010MMTB...41.1220R"><span id="translatedtitle">Ore <span class="hlt">Melting</span> and Reduction in Silicomanganese Production</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ringdalen, Eli; Gaal, Sean; Tangstad, Merete; Ostrovski, Oleg</p> <p>2010-12-01</p> <p>The charge for silicomangansese production consists of manganese ore (often mixed with ferromanganese slag) dolomite or calcite, quartz, and in some cases, other additions. These materials have different <span class="hlt">melting</span> properties, which have a strong effect on reduction and smelting reactions in the production of a silicomanganese alloy. This article discusses properties of Assman, Gabonese, and Companhia Vale do Rio Doce (CVRD) ores, CVRD sinter and high-carbon ferromanganese (HC FeMn) slag, and their change during silicomanganese production. The <span class="hlt">melting</span> and reduction temperatures of these manganese sources were measured in a carbon monoxide atmosphere, using the sessile drop method and a differential thermal analysis/thermogravimetric analysis. Equilibrium phases were analyzed using FACTSage (CRCT, Montreal, Canada and GTT, Aachen, Germany) software. Experimental investigations and an analysis of equilibrium phases revealed significant differences in the <span class="hlt">melting</span> behavior and reduction of different manganese sources. The difference in smelting of CVRD ore and CVRD sinter was attributed to a faster reduction of sinter by the graphite substrate and carbon monoxide. The calculation of equilibrium phases in the reduction process of manganese ores using FACTSage correctly reflects the trends in the production of manganese alloys. The temperature at which the manganese oxide concentration in the slag was reduced below 10 wt pct can be assigned to the top of the coke bed in the silicomanganese furnace. This temperature was in the range 1823 K to 1883 K (1550 °C to 1610 °C).</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2014JMMM..349....9S"><span id="translatedtitle">Magnetic properties of Mn-Bi <span class="hlt">melt</span>-spun ribbons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saito, Tetsuji; Nishimura, Ryuji; Nishio-Hamane, Daisuke</p> <p>2014-01-01</p> <p>Mn-Bi <span class="hlt">melt</span>-spun ribbons with the low temperature phase (LTP) of MnBi were produced by <span class="hlt">melt</span>-spinning and subsequent annealing. The as-rapidly quenched Mn-Bi <span class="hlt">melt</span>-spun ribbons contained some LTP MnBi phase and exhibited a high coercivity exceeding 8 kOe. Annealing of the <span class="hlt">melt</span>-spun ribbons resulted in an increase in the amount of the LTP MnBi phase. A maximum remanence value of 42 emu/g was achieved in Mn50Bi50 <span class="hlt">melt</span>-spun ribbon annealed at 673 K for 1 h. High-temperature measurements revealed that the coercivity of the annealed Mn50Bi50 <span class="hlt">melt</span>-spun ribbon increased with increasing ambient temperature. Although the Mn50Bi50 <span class="hlt">melt</span>-spun ribbons showed a much smaller coercivity than Nd15Fe77B8 <span class="hlt">melt</span>-spun ribbon at room temperature, it exhibited a higher coercivity at temperatures of 473 K and higher. Therefore, the magnetic properties of Mn50Bi50 <span class="hlt">melt</span>-spun ribbon are comparable to those of Nd-Fe-B <span class="hlt">melt</span>-spun ribbon at an ambient temperature of 473 K and become superior to those of Nd-Fe-B <span class="hlt">melt</span>-spun ribbon at 573 K.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=PUBMED&redirectUrl=http://www.ncbi.nlm.nih.gov/pubmed/26032323"><span id="translatedtitle">Regional variability in sea ice <span class="hlt">melt</span> in a changing Arctic.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Perovich, Donald K; Richter-Menge, Jacqueline A</p> <p>2015-07-13</p> <p>In recent years, the Arctic sea ice cover has undergone a precipitous decline in summer extent. The sea ice mass balance integrates heat and provides insight on atmospheric and oceanic forcing. The amount of surface <span class="hlt">melt</span> and bottom <span class="hlt">melt</span> that occurs during the summer <span class="hlt">melt</span> season was measured at 41 sites over the time period 1957 to 2014. There are large regional and temporal variations in both surface and bottom <span class="hlt">melting</span>. Combined surface and bottom <span class="hlt">melt</span> ranged from 16 to 294?cm, with a mean of 101?cm. The mean ice equivalent surface <span class="hlt">melt</span> was 48?cm and the mean bottom <span class="hlt">melt</span> was 53?cm. On average, surface <span class="hlt">melting</span> decreases moving northward from the Beaufort Sea towards the North Pole; however interannual differences in atmospheric forcing can overwhelm the influence of latitude. Substantial increases in bottom <span class="hlt">melting</span> are a major contributor to ice losses in the Beaufort Sea, due to decreases in ice concentration. In the central Arctic, surface and bottom <span class="hlt">melting</span> demonstrate interannual variability, but show no strong temporal trends from 2000 to 2014. This suggests that under current conditions, summer <span class="hlt">melting</span> in the central Arctic is not large enough to completely remove the sea ice cover. PMID:26032323</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1996JGR...10111855D"><span id="translatedtitle">High-frequency isotopic variations in the Mauna Kea tholeiitic basalt sequence: <span class="hlt">Melt</span> zone dispersivity and chromatography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Depaolo, Donald J.</p> <p>1996-05-01</p> <p>A stratigraphically controlled sequence of Sr, Nd, Pb, and He isotope ratio measurements on tholeiitic basalt <span class="hlt">cored</span> by the Hawaii Scientific Drilling Project is analyzed to constrain the dispersivity and chromatographic efficiency of the <span class="hlt">melt</span>-producing zone under Hawaii. The data are interpreted using a simplified model for the transport of isotopic signals through the <span class="hlt">melt</span> zone as magma separates from the upwelling solid by buoyancy-driven porous flow. A constant lava accumulation rate is assumed for the 620-m-thick section of analyzed basalt; a total duration of lava accumulation of 120 kyr is based on Ar-Ar dating. The amplitude-"period" spectrum of the isotopic variations in the lava sequence is determined by Fourier analysis and compared with a predicted amplitude-period spectrum for the mantle magma sources, based on an assumed amplitude-wavelength spectrum for the mantle and a plume upwelling velocity of 20 cm/yr. The isotopic variations in the mantle appear to be substantially attenuated in the lava record. If the attenuation is due to hydrodynamic dispersion in the <span class="hlt">melting</span> zone, then the <span class="hlt">melt</span> zone dispersivity is estimated to be in the range 100-1000 m, depending mainly on the value assumed for the <span class="hlt">melt</span>-matrix velocity contrast. Dispersivity is a crude measure of effective grain size in the <span class="hlt">melt</span> zone; the large values, although strictly only upper limits, suggest that permeability in the <span class="hlt">melt</span> zone is inhomogeneous and some amount of channel development is present. The ratios 3He/4He and 206Pb/204Pb in the Mauna Kea section describe convoluted loops when plotted against one another, consistent with significant chromatographic separation of He and Pb in the <span class="hlt">melt</span> zone. The evidence for chromatography of isotopic signals is consistent with the porous flow model predictions and indicates that the <span class="hlt">melt</span> is maintained moderately close to chemical equilibrium with the solid as it separates. The modeling suggests that generally, chromatography in the <span class="hlt">melting</span> zone causes isotope ratio-ratio relationships observed in the lava record to be severely out-of-phase with those present in the mantle source if the period of the variability is of order 105 years; for periods greater than 106 years the ratios are close to being "in phase," whereas for periods less than 104 years the lava record is hopelessly scrambled.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/1999CoMP..134..202L"><span id="translatedtitle">Low <span class="hlt">melt</span> fraction connectivity of granitic and tonalitic <span class="hlt">melts</span> in a mafic crustal rock at 800°C and 1 GPa</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lupulescu, Afina; Watson, E. Bruce</p> <p></p> <p>In the absence of an externally applied stress, the segregation of small amounts of granitic or tonalitic <span class="hlt">melts</span> from their residual mafic crystals is possible only if the <span class="hlt">melt</span> forms an interconnected network phase. Accordingly, this research focuses on <span class="hlt">melt</span> connectivity at low <span class="hlt">melt</span> fraction (<4 wt% or 5 vol.%). Connectivity of granitic and tonalitic <span class="hlt">melts</span> in amphibole-rich rock was assessed by performing two types of piston-cylinder experiments at 1 GPa and 800°C. The first involved annealing samples that consisted of either alternating layers or homogeneous mixtures of calcic amphibole and metaluminous obsidian powder. The second type of experiment involved creating diffusion couples. Here, an upper cylinder of amphibole-saturated granitic or tonalitic <span class="hlt">melt</span> was placed against a lower cylinder consisting of an amphibole-rich rock containing zero or a small <span class="hlt">melt</span> (granitic or tonalitic) fraction. The upper part of the diffusion couple was doped with ? emitter (151Sm or 14C) and functioned as an infinite <span class="hlt">melt</span> reservoir. The lower part of the diffusion couple was considered to be the host rock. The experiments approached textural equilibrium which allowed us to characterize the wetting behaviour of the calcic amphibole by the hydrous silicic <span class="hlt">melt</span> (granitic or tonalitic). These particular experiments also provided information concerning diffusive transport, because the ? emitter could diffuse through the connected <span class="hlt">melt</span> (liquid) in the amphibole-rich rock. The dihedral angle measurements show that <span class="hlt">melt</span> connectivity was achieved. This conclusion is based on the fact that the dihedral angles, ?, consistently yielded median apparent values of 53°<?<58° for an amphibole-rich rock/granitic <span class="hlt">melt</span> system, and 46°<?<48° for an amphibole-rich rock/tonalitic <span class="hlt">melt</span> system. However, the frequency distribution of ? angles is found to be relatively broad. The results of the diffusion-couple experiments, assessed using the ? radiographic technique, complement the dihedral (wetting) angle measurements by showing that <span class="hlt">melt</span> connectivity is achieved at a <span class="hlt">melt</span> fraction less than 4wt% (5 vol.%).</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2010EGUGA..12.8310B"><span id="translatedtitle">Complexation of Sr in aqueous fluids equilibrated with silicate <span class="hlt">melts</span>: effect of <span class="hlt">melt</span> and fluid composition</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borchert, Manuela; Wilke, Max; Schmidt, Christian; Kvashnina, Kristina</p> <p>2010-05-01</p> <p>At crustal conditions, the fluid-<span class="hlt">melt</span> partitioning of Sr is mainly controlled by the salinity of the fluid and the composition of the <span class="hlt">melt</span> (Borchert et al., 2010). The data show a sharp increase in the Sr partition coefficient with the alumina saturation index (ASI) to a maximum of 0.3 at an ASI of 1.05. Because fluid-<span class="hlt">melt</span> partitioning of a given element depends on its complexation in the fluid and its incorporation in the <span class="hlt">melt</span>, these data imply a change in the Sr speciation at least one of the two phases. For silicate <span class="hlt">melts</span>, Kohn et al. (1990) found only small changes in the first coordination shell of Sr in a suite of <span class="hlt">melts</span> with various degrees of polymerization, and argued that incorporation of Sr in the <span class="hlt">melt</span> should not play a major role in controlling Sr partitioning. For the aqueous fluid, Bai and Koster van Groos (1999) and Webster et al. (1989) suggested a control of the Sr partition coefficient by SrCl2 complexes based on the correlation between partition coefficient and Cl concentration in the fluid after quenching. Both hypotheses cannot explain our partitioning data. Thus, new information on Sr complexation is required. Here, we studied the complexation of Sr in peraluminous or peralkaline <span class="hlt">melt</span> dissolved in aqueous fluids in-situ at elevated PT conditions using hydrothermal diamond-anvil cells (HDAC) and X-ray absorption near edge structure (XANES) spectroscopy. The starting materials were peraluminous or peralkaline glass and H2O or a chloridic solution. The glass was doped with high concentrations of 5000 or 10000 ppm Sr. We used bulk compositions with 10 to 15 wt.% glass to ensure that the <span class="hlt">melt</span> was completely dissolved in the fluid at high PT conditions. For qualitative evaluation, we analyzed the starting glasses and various crystalline compounds and standard solutions. The experiments were performed at beamline ID26 at ESRF (Grenoble, France) using a high resolution emission spectrometer and Si(311) monochromator crystals for high resolution and Si(111) for low resolution measurements. An overall resolution of 1.98 eV (Si(311)) and 3 eV (Si(111)) was achieved using a beamsize of 120x400 ?m, Si(777) analyzer crystals and a Rowland circle diameter of 1 m. Strontium XANES spectra of peraluminous and peralkaline starting glasses show distinct differences in pre-edge, main edge and position of the first EXAFS maximum which is directly correlated to the distance of Sr and its nearest neighbor. Therefore, the spectra indicate an effect of the ASI on the local structure around Sr. Spectra of standard solution at various PT conditions indicate detectable temperature-dependent changes in the intensity and peak width of the white line. The XANES spectra of chloridic solutions with peraluminous or peralkaline <span class="hlt">melt</span> dissolved differ significantly from each other. The latter are similar to the one of the peralkaline starting glass, while this is not the case for solutions with peraluminous <span class="hlt">melt</span>. The spectra of water with dissolved peralkaline <span class="hlt">melt</span> distinctly differ from those using chloridic fluids. In conclusion, the first spectroscopic evidence on Sr complexation at elevated PT condition indicates significant speciation changes in both fluid and <span class="hlt">melt</span>, and suggest ASI-dependent formation of Sr-Si complexes in the fluids. Literature Bai and Koster van Groos (1999), GCA 63, 1117-1131. Borchert et al. (2010), GCA 74, 1057-1076. Kohn et al. (1990), CMP 105, 359-368. Webster et al. (1989), Econ. Geol. 84, 116-134.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASA-TRS&redirectUrl=http://hdl.handle.net/2060/19900014424"><span id="translatedtitle"><span class="hlt">Core</span> sample extractor</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Akins, James; Cobb, Billy; Hart, Steve; Leaptrotte, Jeff; Milhollin, James; Pernik, Mark</p> <p>1989-01-01</p> <p>The problem of retrieving and storing <span class="hlt">core</span> samples from a hole drilled on the lunar surface is addressed. The total depth of the hole in question is 50 meters with a maximum diameter of 100 millimeters. The <span class="hlt">core</span> sample itself has a diameter of 60 millimeters and will be two meters in length. It is therefore necessary to retrieve and store 25 <span class="hlt">core</span> samples per hole. The design utilizes a control system that will stop the mechanism at a certain depth, a cam-linkage system that will fracture the <span class="hlt">core</span>, and a storage system that will save and catalogue the <span class="hlt">cores</span> to be extracted. The Rod Changer and Storage Design Group will provide the necessary tooling to get into the hole as well as to the <span class="hlt">core</span>. The mechanical design for the cam-linkage system as well as the conceptual design of the storage device are described.</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=SCIGOV-MAS&redirectUrl=http://academic.research.microsoft.com/Publication/1562375"><span id="translatedtitle">Scattering of radiowaves by a <span class="hlt">melting</span> layer of precipitation in backward and forward directions</span></a></p> <p><a target="_blank" href="http://academic.research.microsoft.com/">Microsoft Academic Search </a></p> <p>Wei Zhang</p> <p>1994-01-01</p> <p>A <span class="hlt">melting</span> layer of precipitation is composed of <span class="hlt">melting</span> snowflakes (snow particles); the assumption of spherical particles along with mass conservation is used. The <span class="hlt">melting</span> layer is studied by deriving the size distribution of the <span class="hlt">melting</span> snow particles, the thickness of a <span class="hlt">melting</span> layer, the density of a dry snow particle, and the average dielectric constant of a <span class="hlt">melting</span> snow</p> </li> <li> <p><a target="resultTitleLink" href="http://www.science.gov/scigov/desktop/en/ostiblue/service/link/track?type=RESULT&searchId=topic-pages&collectionCode=NASAADS&redirectUrl=http://adsabs.harvard.edu/abs/2004PhDT.......155A"><span id="translatedtitle">Adaptive <span class="hlt">core</span> simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abdel-Khalik, Hany Samy</p> <p></p> <p>The work presented in this thesis is a continuation of a master's thesis research project conducted by the author to gain insight into the applicability of inverse methods to developing adaptive simulation capabilities for <span class="hlt">core</span> physics problems. Use of adaptive simulation is intended to improve the fidelity and robustness of important <span class="hlt">core</span> attributes predictions such as <span class="hlt">core</span> power distribution, thermal margins and <span class="hlt">core</span> reactivity. Adaptive simulation utilizes a selected set of past and current reactor measurements of reactor observables, i.e. in-<span class="hlt">core</span> instrumentations readings, to adapt the simulation in a meaningful way. A meaningful adaption will result in high fidelity and robust adapted <span class="hlt">core</span> simulators models. To perform adaption, we propose an inverse theory approach in which the multitudes of input data to <span class="hlt">core</span> simulators, i.e. reactor physics and thermal-hydraulic data, are to be adjusted to improve agreement with measured observables while keeping <span class="hlt">core</span> simulators models unadapted. At a first glance, devising such adaption for typical <span class="hlt">core</span> simulators models would render the approach impractical. This follows, since <span class="hlt">core</span> simulators are based on very demanding computational models, i.e. based on complex physics models with millions of input data and output observables. This would spawn not only several prohibitive challenges but also numerous disparaging concerns. The challenges include the computational burdens of the sensitivity-type calculations required to construct Jacobian operators for the <span class="hlt">core</span> simulators models. Also, the computational burdens of the uncertainty-type calculations required to estimate the uncertainty information of <span class="hlt">core</span> simulators input data presents a demanding challenge. The concerns however are mainly related to the reliability of the adjusted input data. We demonstrate that the power of our proposed approach is mainly driven by taking advantage of this unfavorable situation. Our contribution begins with the realization that to obtain numerical solutions to demanding computational models, matrix methods are often employed to produce approximately equivalent discretized computational models that may be manipulated further by computers. The discretized models are described by matrix operators that are often rank-deficient, i.e. ill-posed. We introduce a novel set of matrix algorithms, denoted by Efficient Subspace Methods (ESM), intended to approximate the action of very large, dense, and numerically rank-deficient matrix operators. We demonstrate that significant reductions in both computational and storage burdens can be attained for a typical BWR <span class="hlt">core</span> simulator adaption problem without compromising the quality of the adaption. We demonstrate robust and high fidelity adaption utilizing a virtual <span class="hlt">core</span>, e.g. <span class="hlt">core</span> simulator predicted observables with the virtual <span class="hlt">core</span> either based upon a modified version of the <span class="hlt">core</span> simulator whose input data are to be adjusted or an entirely different <span class="hlt">core</span> simulator. Further, one specific application of ESM is demonstrated, that is being the determination of the uncertainties of important <span class="hlt">core</span> attributes such as <span class="hlt">core</span> reactivity and <span class="hlt">core</span> power distribution due to the available ENDF/B cross-sections uncertainties. The use of ESM is however not limited to adaptive <span class="hlt">core</span> simulation techniques only, but a wide range of engineering applications may easily benefit from the introduced algorithms, e.g. machine learning and information retrieval techniques highly depends on finding low rank approximations to large scale matrices. In the appendix, we present a stand-alone paper that presents a generalized framework for ESM, including the mathematical theory behind the algorithms and several demonstrative applications that are central to many engineering arenas---(a) sensitivity analysis, (b) parameter estimation, and (c) uncertainty analysis. We choose to do so to allow other engineers, applied mathematicians, and scientists from other scientific disciplines to take direct advantage of ESM without having to sail across the sea of reactor <span class="hlt">core</span> calculations.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. 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