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Sample records for mass transport measurements

  1. Mass transport measurements and modeling for chemical vapor infiltration

    SciTech Connect

    Starr, T.L.; Chiang, D.Y.; Fiadzo, O.G.; Hablutzel, N.

    1997-12-01

    This project involves experimental and modeling investigation of densification behavior and mass transport in fiber preforms and partially densified composites, and application of these results to chemical vapor infiltration (CVI) process modeling. This supports work on-going at ORNL in process development for fabrication of ceramic matrix composite (CMC) tubes. Tube-shaped composite preforms are fabricated at ORNL with Nextel{trademark} 312 fiber (3M Corporation, St. Paul, MN) by placing and compressing several layers of braided sleeve on a tubular mandrel. In terms of fiber architecture these preforms are significantly different than those made previously with Nicalon{trademark} fiber (Nippon Carbon Corp., Tokyo, Japan) square weave cloth. The authors have made microstructure and permeability measurements on several of these preforms and a few partially densified composites so as to better understand their densification behavior during CVI.

  2. Measurements of the transport efficiency of the fragment mass analyzer

    SciTech Connect

    Back, B.B.; Blumenthal, D.J.; Davids, C.N.

    1995-08-01

    Extensive calculations of the transport of reaction products were carried out during the design phase of the instrument using the computer code GIOS. These show that the energy acceptance depends strongly on the angular deviation from the optical axis of the instrument. In order to reliably measure cross sections using this instrument it is therefore necessary to verify these calculations empirically.

  3. Dynamic characterization of external and internal mass transport in heterotrophic biofilms from microsensors measurements.

    PubMed

    Guimerà, Xavier; Dorado, Antonio David; Bonsfills, Anna; Gabriel, Gemma; Gabriel, David; Gamisans, Xavier

    2016-10-01

    Knowledge of mass transport mechanisms in biofilm-based technologies such as biofilters is essential to improve bioreactors performance by preventing mass transport limitation. External and internal mass transport in biofilms was characterized in heterotrophic biofilms grown on a flat plate bioreactor. Mass transport resistance through the liquid-biofilm interphase and diffusion within biofilms were quantified by in situ measurements using microsensors with a high spatial resolution (<50 μm). Experimental conditions were selected using a mathematical procedure based on the Fisher Information Matrix to increase the reliability of experimental data and minimize confidence intervals of estimated mass transport coefficients. The sensitivity of external and internal mass transport resistances to flow conditions within the range of typical fluid velocities over biofilms (Reynolds numbers between 0.5 and 7) was assessed. Estimated external mass transfer coefficients at different liquid phase flow velocities showed discrepancies with studies considering laminar conditions in the diffusive boundary layer near the liquid-biofilm interphase. The correlation of effective diffusivity with flow velocities showed that the heterogeneous structure of biofilms defines the transport mechanisms inside biofilms. Internal mass transport was driven by diffusion through cell clusters and aggregates at Re below 2.8. Conversely, mass transport was driven by advection within pores, voids and water channels at Re above 5.6. Between both flow velocities, mass transport occurred by a combination of advection and diffusion. Effective diffusivities estimated at different biofilm densities showed a linear increase of mass transport resistance due to a porosity decrease up to biofilm densities of 50 g VSS·L(-1). Mass transport was strongly limited at higher biofilm densities. Internal mass transport results were used to propose an empirical correlation to assess the effective diffusivity

  4. Dynamic characterization of external and internal mass transport in heterotrophic biofilms from microsensors measurements.

    PubMed

    Guimerà, Xavier; Dorado, Antonio David; Bonsfills, Anna; Gabriel, Gemma; Gabriel, David; Gamisans, Xavier

    2016-10-01

    Knowledge of mass transport mechanisms in biofilm-based technologies such as biofilters is essential to improve bioreactors performance by preventing mass transport limitation. External and internal mass transport in biofilms was characterized in heterotrophic biofilms grown on a flat plate bioreactor. Mass transport resistance through the liquid-biofilm interphase and diffusion within biofilms were quantified by in situ measurements using microsensors with a high spatial resolution (<50 μm). Experimental conditions were selected using a mathematical procedure based on the Fisher Information Matrix to increase the reliability of experimental data and minimize confidence intervals of estimated mass transport coefficients. The sensitivity of external and internal mass transport resistances to flow conditions within the range of typical fluid velocities over biofilms (Reynolds numbers between 0.5 and 7) was assessed. Estimated external mass transfer coefficients at different liquid phase flow velocities showed discrepancies with studies considering laminar conditions in the diffusive boundary layer near the liquid-biofilm interphase. The correlation of effective diffusivity with flow velocities showed that the heterogeneous structure of biofilms defines the transport mechanisms inside biofilms. Internal mass transport was driven by diffusion through cell clusters and aggregates at Re below 2.8. Conversely, mass transport was driven by advection within pores, voids and water channels at Re above 5.6. Between both flow velocities, mass transport occurred by a combination of advection and diffusion. Effective diffusivities estimated at different biofilm densities showed a linear increase of mass transport resistance due to a porosity decrease up to biofilm densities of 50 g VSS·L(-1). Mass transport was strongly limited at higher biofilm densities. Internal mass transport results were used to propose an empirical correlation to assess the effective diffusivity

  5. Measurements of Combined Axial Mass and Heat Transport in He II.

    ERIC Educational Resources Information Center

    Johnson, Warren W.; Jones, Michael C.

    An experiment was performed that allowed measurements of both axial mass and heat transport of He-II (the superfluid phase of helium 4) in a long tube. The apparatus allowed the pressure difference and the temperature difference across the flow tube to each be independently adjusted, and the resulting steady-state values of net fluid velocity and…

  6. Density-of-states effective mass and scattering parameter measurements by transport phenomena in thin films

    NASA Astrophysics Data System (ADS)

    Young, D. L.; Coutts, T. J.; Kaydanov, V. I.

    2000-02-01

    A novel machine has been developed to measure transport coefficients in the temperature range of 50-350 K of thin films deposited on electrically insulating substrates. The measured coefficients—resistivity, Hall, Seebeck, and Nernst—are applied to solutions of the Boltzmann transport equation to give information about the film's density-of-states effective mass, the Fermi energy level, and an energy-dependent scattering parameter. The machine is designed to eliminate or compensate for simultaneously occurring transport phenomena that would interfere with the desired measured quantity, while allowing for all four coefficients to be measured on the same sample. An average density-of-states effective mass value of 0.29±0.04me was measured on the transparent conductive oxide, cadmium stannate (CTO), over a carrier concentration range of 2-7×1020cm-3. This effective mass value matched previous results obtained by optical and thermoelectric modeling. The measured scattering parameter indicates that neutral impurities or a mixture of scattering mechanisms may inhibit the transport of carriers in CTO.

  7. Bioreactor Mass Transport Studies

    NASA Technical Reports Server (NTRS)

    Kleis, Stanley J.; Begley, Cynthia M.

    1997-01-01

    The objectives of the proposed research efforts were to develop both a simulation tool and a series of experiments to provide a quantitative assessment of mass transport in the NASA rotating wall perfused vessel (RWPV) bioreactor to be flown on EDU#2. This effort consisted of a literature review of bioreactor mass transport studies, the extension of an existing scalar transport computer simulation to include production and utilization of the scalar, and the evaluation of experimental techniques for determining mass transport in these vessels. Since mass transport at the cell surface is determined primarily by the relative motion of the cell assemblage and the surrounding fluid, a detailed assessment of the relative motion was conducted. Results of the simulations of the motion of spheres in the RWPV under microgravity conditions are compared with flight data from EDU#1 flown on STS-70. The mass transport across the cell membrane depends upon the environment, the cell type, and the biological state of the cell. Results from a literature review of cell requirements of several scalars are presented. As a first approximation, a model with a uniform spatial distribution of utilization or production was developed and results from these simulations are presented. There were two candidate processes considered for the experimental mass transport evaluations. The first was to measure the dissolution rate of solid or gel beads. The second was to measure the induced fluorescence of beads as a stimulant (for example hydrogen peroxide) is infused into the vessel. Either technique would use video taped images of the process for recording the quantitative results. Results of preliminary tests of these techniques are discussed.

  8. Measurement and visualization of mass transport for the flowing atmospheric pressure afterglow (FAPA) ambient mass-spectrometry source.

    PubMed

    Pfeuffer, Kevin P; Ray, Steven J; Hieftje, Gary M

    2014-05-01

    Ambient desorption/ionization mass spectrometry (ADI-MS) has developed into an important analytical field over the last 9 years. The ability to analyze samples under ambient conditions while retaining the sensitivity and specificity of mass spectrometry has led to numerous applications and a corresponding jump in the popularity of this field. Despite the great potential of ADI-MS, problems remain in the areas of ion identification and quantification. Difficulties with ion identification can be solved through modified instrumentation, including accurate-mass or MS/MS capabilities for analyte identification. More difficult problems include quantification because of the ambient nature of the sampling process. To characterize and improve sample volatilization, ionization, and introduction into the mass spectrometer interface, a method of visualizing mass transport into the mass spectrometer is needed. Schlieren imaging is a well-established technique that renders small changes in refractive index visible. Here, schlieren imaging was used to visualize helium flow from a plasma-based ADI-MS source into a mass spectrometer while ion signals were recorded. Optimal sample positions for melting-point capillary and transmission-mode (stainless steel mesh) introduction were found to be near (within 1 mm of) the mass spectrometer inlet. Additionally, the orientation of the sampled surface plays a significant role. More efficient mass transport resulted for analyte deposits directly facing the MS inlet. Different surfaces (glass slide and rough surface) were also examined; for both it was found that the optimal position is immediately beneath the MS inlet.

  9. Measurement and Visualization of Mass Transport for the Flowing Atmospheric Pressure Afterglow (FAPA) Ambient Mass-Spectrometry Source

    PubMed Central

    Pfeuffer, Kevin P.; Ray, Steven J.; Hieftje, Gary M.

    2014-01-01

    Ambient desorption/ionization mass spectrometry (ADI-MS) has developed into an important analytical field over the last nine years. The ability to analyze samples under ambient conditions while retaining the sensitivity and specificity of mass spectrometry has led to numerous applications and a corresponding jump in the popularity of this field. Despite the great potential of ADI-MS, problems remain in the areas of ion identification and quantification. Difficulties with ion identification can be solved through modified instrumentation, including accurate-mass or MS/MS capabilities for analyte identification. More difficult problems include quantification due to the ambient nature of the sampling process. To characterize and improve sample volatilization, ionization, and introduction into the mass-spectrometer interface, a method of visualizing mass transport into the mass spectrometer is needed. Schlieren imaging is a well-established technique that renders small changes in refractive index visible. Here, schlieren imaging was used to visualize helium flow from a plasma-based ADI-MS source into a mass spectrometer while ion signals were recorded. Optimal sample positions for melting-point capillary and transmission-mode (stainless steel mesh) introduction were found to be near (within 1 mm of) the mass spectrometer inlet. Additionally, the orientation of the sampled surface plays a significant role. More efficient mass transport resulted for analyte deposits directly facing the MS inlet. Different surfaces (glass slide and rough surface) were also examined; for both it was found that the optimal position is immediately beneath the MS inlet. PMID:24658804

  10. Mass-transport limitation to in-cloud reaction rates: Implications of new accommodation coefficient measurements

    SciTech Connect

    Schwartz, S.E.

    1988-10-01

    Although it has been recognized for some time that the rate of reactive uptake of gases in cloudwater can depend on the value of the mass-accommodation coefficient (..cap alpha..) describing interfacial mass transport (MT), definitive evaluation of such rates is only now becoming possible with the availability of measurements of ..cap alpha.. for gases of atmospheric interest at air-water interfaces. Examination of MT limitation to the rate of in-cloud aqueous-phase oxidation of SO/sub 2/ by O/sub 3/ and H/sub 2/O/sub 2/ shows that despite the low value of ..cap alpha../sub O3/ (5 /times/ 10/sup /minus/4/), interfacial MT of this species is not limiting under essentially all conditions of interest; the high values of ..cap alpha.. for SO/sub 2/ (greater than or equal to 0.2) and H/sub 2/O/sub 2/ (greater than or equal to 0.08) indicate no interfacial MT limitation for these species also. Although gas- and aqueous-phase MT can be limiting under certain extremes of conditions, treating the system as under chemical kinetic control is generally an excellent approximation. Interfacial MT limitation also is found not to hinder the rate of H/sub 2/O/sub 2/ formation by aqueous-phase disproportionation of HO/sub 2/. Finally, the rapid uptake of N/sub 2/O/sub 5/ by cloud droplets implies that the yield of aqueous HNO/sub 3/ from in-cloud gas-phase oxidation of NO/sub 2/by O/sub 3/ can be substantial even under daytime conditions. This report consists of copies of viewgraphs prepared for this presentation.

  11. Automated transportable mass spectrometer

    NASA Astrophysics Data System (ADS)

    Echo, M. W.

    1981-09-01

    The need was identified for a mass spectrometer (MS) which can be conveniently transported among several facilities for rapid verification of the isotopic composition of special nuclear material. This requirement for a light weight, transportable MS for U and Pu mass analysis was met by deleting the gas chromograph (GC) portions of a Hewlett-Packard Model 5992 Quadrupole GCMS and substituting a vacuum lock sample entry system. A programmable power supply and vacuum gauge were added and circuitry modifications were made to enable use of the supplied software.

  12. Low tritium partial pressure permeation system for mass transport measurement in lead lithium eutectic

    DOE PAGES

    Pawelko, R. J.; Shimada, M.; Katayama, K.; Fukada, S.; Humrickhouse, P. W.; Terai, T.

    2015-11-28

    This paper describes a new experimental system designed to investigate tritium mass transfer properties in materials important to fusion technology. Experimental activities were carried out at the Safety and Tritium Applied Research (STAR) facility located at the Idaho National Laboratory (INL). The tritium permeation measurement system was developed as part of the Japan/US TITAN collaboration to investigate tritium mass transfer properties in liquid lead lithium eutectic (LLE) alloy. The experimental system is configured to measure tritium mass transfer properties at low tritium partial pressures. Initial tritium permeation scoping tests were conducted on a 1 mm thick α-Fe plate to determinemore » operating parameters and to validate the experimental technique. A second series of permeation tests was then conducted with the α-Fe plate covered with an approximately 8.5 mm layer of liquid lead lithium eutectic alloy (α-Fe/LLE). We present preliminary tritium permeation data for α-Fe and α-Fe/LLE at temperatures between 400 and 600°C and at tritium partial pressures between 1.7E-3 and 2.5 Pa in helium. Preliminary results for the α-Fe plate and α-Fe/LLE indicate that the data spans a transition region between the diffusion-limited regime and the surface-limited regime. In conclusion, additional data is required to determine the existence and range of a surface-limited regime.« less

  13. Low tritium partial pressure permeation system for mass transport measurement in lead lithium eutectic

    SciTech Connect

    Pawelko, R. J.; Shimada, M.; Katayama, K.; Fukada, S.; Humrickhouse, P. W.; Terai, T.

    2015-11-28

    This paper describes a new experimental system designed to investigate tritium mass transfer properties in materials important to fusion technology. Experimental activities were carried out at the Safety and Tritium Applied Research (STAR) facility located at the Idaho National Laboratory (INL). The tritium permeation measurement system was developed as part of the Japan/US TITAN collaboration to investigate tritium mass transfer properties in liquid lead lithium eutectic (LLE) alloy. The experimental system is configured to measure tritium mass transfer properties at low tritium partial pressures. Initial tritium permeation scoping tests were conducted on a 1 mm thick α-Fe plate to determine operating parameters and to validate the experimental technique. A second series of permeation tests was then conducted with the α-Fe plate covered with an approximately 8.5 mm layer of liquid lead lithium eutectic alloy (α-Fe/LLE). We present preliminary tritium permeation data for α-Fe and α-Fe/LLE at temperatures between 400 and 600°C and at tritium partial pressures between 1.7E-3 and 2.5 Pa in helium. Preliminary results for the α-Fe plate and α-Fe/LLE indicate that the data spans a transition region between the diffusion-limited regime and the surface-limited regime. In conclusion, additional data is required to determine the existence and range of a surface-limited regime.

  14. Mass Transport within Soils

    SciTech Connect

    McKone, Thomas E.

    2009-03-01

    Contaminants in soil can impact human health and the environment through a complex web of interactions. Soils exist where the atmosphere, hydrosphere, geosphere, and biosphere converge. Soil is the thin outer zone of the earth's crust that supports rooted plants and is the product of climate and living organisms acting on rock. A true soil is a mixture of air, water, mineral, and organic components. The relative proportions of these components determine the value of the soil for agricultural and for other human uses. These proportions also determine, to a large extent, how a substance added to soil is transported and/or transformed within the soil (Spositio, 2004). In mass-balance models, soil compartments play a major role, functioning both as reservoirs and as the principal media for transport among air, vegetation, surface water, deeper soil, and ground water (Mackay, 2001). Quantifying the mass transport of chemicals within soil and between soil and atmosphere is important for understanding the role soil plays in controlling fate, transport, and exposure to multimedia pollutants. Soils are characteristically heterogeneous. A trench dug into soil typically reveals several horizontal layers having different colors and textures. As illustrated in Figure 1, these multiple layers are often divided into three major horizons: (1) the A horizon, which encompasses the root zone and contains a high concentration of organic matter; (2) the B horizon, which is unsaturated, lies below the roots of most plants, and contains a much lower organic carbon content; and (3) the C horizon, which is the unsaturated zone of weathered parent rock consisting of bedrock, alluvial material, glacial material, and/or soil of an earlier geological period. Below these three horizons lies the saturated zone - a zone that encompasses the area below ground surface in which all interconnected openings within the geologic media are completely filled with water. Similarly to the unsaturated zone

  15. Integral measurements of mass transport and heat content in the Strait of Gibraltar from acoustic transmissions

    NASA Astrophysics Data System (ADS)

    Send, Uwe; Worcester, Peter F.; Cornuelle, Bruce D.; Tiemann, Christopher O.; Baschek, Burkard

    those derived from current-meter data. The fractional uncertainty variance for the lower layer tidal transport from a single tomographic path was estimated to be 0.017 (i.e. 98% of the a priori tidal transport variance was resolved). The spatial scales of the sub-tidal flow are thought to be significantly shorter than those of the tidal flow, however, which means that a more elaborate monitoring network is required to achieve the same performance for sub-tidal variability. Finally, sum travel times from the reciprocal transmissions were found to provide good measurements of the temperature and heat content in the lower layer.

  16. Location - Dependent Coronary Artery Diffusive and Convective Mass Transport Properties of a Lipophilic Drug Surrogate Measured Using Nonlinear Microscopy

    PubMed Central

    Keyes, Joseph T.; Simon, Bruce R.; Vande Geest, Jonathan P.

    2013-01-01

    Purpose Arterial wall mass transport properties dictate local distribution of biomolecules or locally delivered dugs. Knowing how these properties vary between coronary artery locations could provide insight into how therapy efficacy is altered between arterial locations. Methods We introduced an indocarbocyanine drug surrogate to the lumens of left anterior descending and right coronary (LADC; RC) arteries from pigs with or without a pressure gradient. Interstitial fluorescent intensity was measured on live samples with multiphoton microscopy. We also measured binding to porcine coronary SMCs in monoculture. Results Diffusive transport constants peaked in the middle sections of the LADC and RC arteries by 2.09 and 2.04 times, respectively, compared to the proximal and distal segments. There was no statistical difference between the average diffusivity value between LADC and RC arteries. The convection coefficients had an upward trend down each artery, with the RC being higher than the LADC by 3.89 times. Conclusions This study demonstrates that the convective and diffusive transport of lipophilic molecules changes between the LADC and the RC arteries as well as along their length. These results may have important implications in optimizing drug delivery for the treatment of coronary artery disease. PMID:23224981

  17. Precision mass measurements

    NASA Astrophysics Data System (ADS)

    Gläser, M.; Borys, M.

    2009-12-01

    Mass as a physical quantity and its measurement are described. After some historical remarks, a short summary of the concept of mass in classical and modern physics is given. Principles and methods of mass measurements, for example as energy measurement or as measurement of weight forces and forces caused by acceleration, are discussed. Precision mass measurement by comparing mass standards using balances is described in detail. Measurement of atomic masses related to 12C is briefly reviewed as well as experiments and recent discussions for a future new definition of the kilogram, the SI unit of mass.

  18. Out-of-focus effects on microscale schlieren measurements of mass transport in a microfluidic device

    NASA Astrophysics Data System (ADS)

    Chen, Shao-Tuan; Sun, Chen-li

    2016-08-01

    The microscale schlieren technique provides a means for a non-invasive, full-field measurement for mixing microfluidics with excellent sensitivity and resolution. Nevertheless, an out-of-focus effect due to microscopic optics may lead to undesirable errors in quantifying the gradient information at high degrees of magnification. If the channel in the microfluidic device under study is too deep, light deflection caused by inhomogeneity located far from the focal plane may contributes little to the intensity change on the image plane. To address this issue, we propose the use of a weighting function that approximates a Gaussian profile with an optical-system-dependable width. We assume that the resultant intensity change is proportional to a weighted sum of the gradient across the channel depth and acquire micro-schlieren images of fluid mixing in a T-junction microchannel at various positions along the optical axis. For each objective, the width of the weighting function is then determined iteratively by curve fitting the ratio of changes in grayscale readouts for out-of-focus and focus micro-schlieren images. The standard deviation in the Gaussian distribution facilitates the quantification of the out-of-focus effect. In addition, we measure the sensitivities of a microscale schlieren system equipped with different objectives and compare the values to the model. Despite its better resolution, we find that an objective with higher magnification suffers from a more severe out-of-focus effect and a loss of sensitivity. Equations are proposed for estimations of the standard deviation and the sensitivity of microscale schlieren measurements. The outcome will facilitate the selection of proper microchannel depths for various microscale schlieren systems or vice versa, thus improving the precision of micro-schlieren measurements in microfluidic devices.

  19. Urban Mass Transportation.

    ERIC Educational Resources Information Center

    Mervine, K. E.

    This bibliography is part of a series of Environmental Resource Packets prepared under a grant from EXXON Education Foundation. The most authoritative and accessible references in the urban transportation field are reviewed. The authors, publisher, point of view, level, and summary are given for each reference. The references are categorized…

  20. Measurement of Mass.

    ERIC Educational Resources Information Center

    Zimmerer, Robert W.

    1983-01-01

    Various instruments and techniques for measuring mass are discussed, focusing on the physics behind techniques employed. Equal-arm balances, electronic substitution balance (using electromagnetic force), non-gravimetric weighing (intertial-mass measurement) are among the instruments/techniques considered. (JN)

  1. Mass Transport in Global Geophysical Fluids

    NASA Technical Reports Server (NTRS)

    Chao, B. F.

    1999-01-01

    Mass transports occurring in the atmosphere-hydrosphere-solid Earth-core system (the "global geophysical fluids") are important geophysical phenomena. They occur on all temporal and spatial scales. Examples include air mass and ocean circulations, tides, hydrological water redistribution, mantle processes such as post-glacial rebound, earthquakes and tectonic motions, and core geodynamo activities. With only a few exceptions on the Earth surface, the temporal history and spatial pattern of such mass transport are often not amenable to direct observations. Space geodesy techniques, however, have the capability of monitoring certain direct consequences of the mass transport, including Earth's rotation variations, gravitational field variations, and the geocenter motion. These techniques include the very-long-baseline interferometry, satellite laser ranging and Doppler tracking, and the Global Positioning System, all entail global observational networks. While considerable advances have been made in observing and understanding of the dynamics of Earth's rotation, only the lowest-degree gravitational variations have been observed and limited knowledge of geocenter motion obtained. New space missions, projects and initiatives promise to further improve the measurements and hence our knowledge about the global mass transports. The latter contributes to our understanding and modeling capability of the geophysical processes that produce and regulate the mass transports, as well as the solid Earth's response to such changes in constraining the modeling of Earth's mechanical properties.

  2. Top quark mass measurements

    SciTech Connect

    Hill, Christopher S.; /UC, Santa Barbara

    2004-12-01

    The top quark, with its extraordinarily large mass (nearly that of a gold atom), plays a significant role in the phenomenology of EWSB in the Standard Model. In particular, the top quark mass when combined with the W mass constrains the mass of the as yet unobserved Higgs boson. Thus, a precise determination of the mass of the top quark is a principal goal of the CDF and D0 experiments. With the data collected thus far in Runs 1 and 2 of the Tevatron, CDF and D0 have measured the top quark mass in both the lepton+jets and dilepton decay channels using a variety of complementary experimental techniques. The author presents an overview of the most recent of the measurements.

  3. Absolute neutrino mass measurements

    SciTech Connect

    Wolf, Joachim

    2011-10-06

    The neutrino mass plays an important role in particle physics, astrophysics and cosmology. In recent years the detection of neutrino flavour oscillations proved that neutrinos carry mass. However, oscillation experiments are only sensitive to the mass-squared difference of the mass eigenvalues. In contrast to cosmological observations and neutrino-less double beta decay (0v2{beta}) searches, single {beta}-decay experiments provide a direct, model-independent way to determine the absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy.Currently the best kinematic upper limits on the neutrino mass of 2.2eV have been set by two experiments in Mainz and Troitsk, using tritium as beta emitter. The next generation tritium {beta}-experiment KATRIN is currently under construction in Karlsruhe/Germany by an international collaboration. KATRIN intends to improve the sensitivity by one order of magnitude to 0.2eV. The investigation of a second isotope ({sup 137}Rh) is being pursued by the international MARE collaboration using micro-calorimeters to measure the beta spectrum. The technology needed to reach 0.2eV sensitivity is still in the R and D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2{beta} decay and single {beta}-decay.

  4. Top Quark Mass Measurements

    SciTech Connect

    Heinson, A.P.; /UC, Riverside

    2006-08-01

    First observed in 1995, the top quark is one of a pair of third-generation quarks in the Standard Model of particle physics. It has charge +2/3e and a mass of 171.4 GeV, about 40 times heavier than its partner, the bottom quark. The CDF and D0 collaborations have identified several hundred events containing the decays of top-antitop pairs in the large dataset collected at the Tevatron proton-antiproton collider over the last four years. They have used these events to measure the top quark's mass to nearly 1% precision and to study other top quark properties. The mass of the top quark is a fundamental parameter of the Standard Model, and knowledge of its value with small uncertainty allows us to predict properties of the as-yet-unobserved Higgs boson. This paper presents the status of the measurements of the top quark mass.

  5. Top Quark Mass Measurements

    SciTech Connect

    Heinson, A. P.

    2006-11-17

    First observed in 1995, the top quark is one of a pair of third-generation quarks in the Standard Model of particle physics. It has charge +2/3e and a mass of 171.4 GeV, about 40 times heavier than its partner, the bottom quark. The CDF and DO collaborations have identified several hundred events containing the decays of top-antitop pairs in the large dataset collected at the Tevatron proton-antiproton collider over the last four years. They have used these events to measure the top quark's mass to nearly 1% precision and to study other top quark properties. The mass of the top quark is a fundamental parameter of the Standard Model, and knowledge of its value with small uncertainty allows us to predict properties of the as-yet-unobserved Higgs boson. This paper presents the status of the measurements of the top quark mass. It is based on a talk I gave at the Conference on the Intersections of Particle and Nuclear Physics in Puerto Rico, May 2006, which also included discussion of measurements of other top quark properties.

  6. Top quark mass measurements

    SciTech Connect

    L. Cerrito

    2004-07-16

    Preliminary results on the measurement of the top quark mass at the Tevatron Collider are presented. In the dilepton decay channel, the CDF Collaboration measures m{sub t} = 175.0{sub -16.9}{sup +17.4}(stat.){+-}8.4(syst.) GeV/c{sup 2}, using a sample of {approx} 126 pb{sup -1} of proton-antiproton collision data at {radical}s = 1.96 TeV (Run II). In the lepton plus jets channel, the CDF Collaboration measures 177.5{sub -9.4}{sup +12.7}(stat.) {+-} 7.1(syst.) GeV/c{sup 2}, using a sample of {approx} 102 pb{sup -1} at {radical}s = 1.96 TeV. The D0 Collaboration has newly applied a likelihood technique to improve the analysis of {approx} 125 pb{sup -1} of proton-antiproton collisions at {radical}s = 1.8 TeV (Run I), with the result: m{sub t} = 180.1 {+-} 3.6(stat.) {+-}3.9(syst.) GeV/c{sup 2}. The latter is combined with all the measurements based on the data collected in Run I to yield the most recent and comprehensive experimental determination of the top quark mass: m{sub t} = 178.0 {+-} 2.7(stat.) {+-} 3.3(syst.) GeV/c{sup 2}.

  7. Oxygen Mass Transport in Stented Coronary Arteries.

    PubMed

    Murphy, Eoin A; Dunne, Adrian S; Martin, David M; Boyle, Fergal J

    2016-02-01

    Oxygen deficiency, known as hypoxia, in arterial walls has been linked to increased intimal hyperplasia, which is the main adverse biological process causing in-stent restenosis. Stent implantation has significant effects on the oxygen transport into the arterial wall. Elucidating these effects is critical to optimizing future stent designs. In this study the most advanced oxygen transport model developed to date was assessed in two test cases and used to compare three coronary stent designs. Additionally, the predicted results from four simplified blood oxygen transport models are compared in the two test cases. The advanced model showed good agreement with experimental measurements within the mass-transfer boundary layer and at the luminal surface; however, more work is needed in predicting the oxygen transport within the arterial wall. Simplifying the oxygen transport model within the blood flow produces significant errors in predicting the oxygen transport in arteries. This study can be used as a guide for all future numerical studies in this area and the advanced model could provide a powerful tool in aiding design of stents and other cardiovascular devices.

  8. The W Boson Mass Measurement

    NASA Astrophysics Data System (ADS)

    Kotwal, Ashutosh V.

    2016-10-01

    The measurement of the W boson mass has been growing in importance as its precision has improved, along with the precision of other electroweak observables and the top quark mass. Over the last decade, the measurement of the W boson mass has been led at hadron colliders. Combined with the precise measurement of the top quark mass at hadron colliders, the W boson mass helped to pin down the mass of the Standard Model Higgs boson through its induced radiative correction on the W boson mass. With the discovery of the Higgs boson and the measurement of its mass, the electroweak sector of the Standard Model is over-constrained. Increasing the precision of the W boson mass probes new physics at the TeV-scale. We summarize an extensive Tevatron (1984-2011) program to measure the W boson mass at the CDF and Dø experiments. We highlight the recent Tevatron measurements and prospects for the final Tevatron measurements.

  9. Efficient mass transport by optical advection

    NASA Astrophysics Data System (ADS)

    Kajorndejnukul, Veerachart; Sukhov, Sergey; Dogariu, Aristide

    2015-10-01

    Advection is critical for efficient mass transport. For instance, bare diffusion cannot explain the spatial and temporal scales of some of the cellular processes. The regulation of intracellular functions is strongly influenced by the transport of mass at low Reynolds numbers where viscous drag dominates inertia. Mimicking the efficacy and specificity of the cellular machinery has been a long time pursuit and, due to inherent flexibility, optical manipulation is of particular interest. However, optical forces are relatively small and cannot significantly modify diffusion properties. Here we show that the effectiveness of microparticle transport can be dramatically enhanced by recycling the optical energy through an effective optical advection process. We demonstrate theoretically and experimentally that this new advection mechanism permits an efficient control of collective and directional mass transport in colloidal systems. The cooperative long-range interaction between large numbers of particles can be optically manipulated to create complex flow patterns, enabling efficient and tunable transport in microfluidic lab-on-chip platforms.

  10. Mass partitioning effects in diffusion transport.

    PubMed

    Kojic, Milos; Milosevic, Miljan; Wu, Suhong; Blanco, Elvin; Ferrari, Mauro; Ziemys, Arturas

    2015-08-28

    Frequent mass exchange takes place in a heterogeneous environment among several phases, where mass partitioning may occur at the interface of phases. Analytical and computational methods for diffusion do not usually incorporate molecule partitioning masking the true picture of mass transport. Here we present a computational finite element methodology to calculate diffusion mass transport with a partitioning phenomenon included and the analysis of the effects of partitioning. Our numerical results showed that partitioning controls equilibrated mass distribution as expected from analytical solutions. The experimental validation of mass release from drug-loaded nanoparticles showed that partitioning might even dominate in some cases with respect to diffusion itself. The analysis of diffusion kinetics in the parameter space of partitioning and diffusivity showed that partitioning is an extremely important parameter in systems, where mass diffusivity is fast and that the concentration of nanoparticles can control payload retention inside nanoparticles. The computational and experimental results suggest that partitioning and physiochemical properties of phases play an important, if not crucial, role in diffusion transport and should be included in the studies of mass transport processes.

  11. Mass partitioning effects in diffusion transport.

    PubMed

    Kojic, Milos; Milosevic, Miljan; Wu, Suhong; Blanco, Elvin; Ferrari, Mauro; Ziemys, Arturas

    2015-08-28

    Frequent mass exchange takes place in a heterogeneous environment among several phases, where mass partitioning may occur at the interface of phases. Analytical and computational methods for diffusion do not usually incorporate molecule partitioning masking the true picture of mass transport. Here we present a computational finite element methodology to calculate diffusion mass transport with a partitioning phenomenon included and the analysis of the effects of partitioning. Our numerical results showed that partitioning controls equilibrated mass distribution as expected from analytical solutions. The experimental validation of mass release from drug-loaded nanoparticles showed that partitioning might even dominate in some cases with respect to diffusion itself. The analysis of diffusion kinetics in the parameter space of partitioning and diffusivity showed that partitioning is an extremely important parameter in systems, where mass diffusivity is fast and that the concentration of nanoparticles can control payload retention inside nanoparticles. The computational and experimental results suggest that partitioning and physiochemical properties of phases play an important, if not crucial, role in diffusion transport and should be included in the studies of mass transport processes. PMID:26204522

  12. Mass meters for liquid measurement

    SciTech Connect

    Apple, C.

    1995-12-01

    Flowmeters that are capable of providing a direct mass flow measurement include: Coriolis, thermal, gyroscopic and angular momentum. However, Coriolis meters are the only commercially viable device that can cover the breadth of measurements required by the petroleum industry. In addition to providing a direct mass flow measurement, Coriolis meters are extremely accurate, typically {+-}0.1 % to {+-}0.2 %. The advantage of measuring mass is that the mass of a fluid is unaffected by changes in process temperature and pressure. Whereas, volume measurements must be corrected to standard conditions of temperature and pressure for accounting purposes. Although measuring a product on a mass basis would be the simplest approach, most petroleum products are accounted for on a volume basis. This is primarily because only volumetric flowmeters were available prior to the introduction of industrial quality Coriolis meter in the early 1980`s. Due to the lack of means to perform a mass measurement, the petroleum industry has standardized on volume measurement. Systems and procedures are currently in place for performing and verifying volume measurements. Therefore, the petroleum industry will be slow in moving to mass measurement. Coriolis meters are currently gaining acceptance in the petroleum industry for the metering of light hydrocarbons, which are difficult to properly account for on a volume basis. However, due to the many advantages that Coriolis meters provide, they will become a preferred flow measurement device for all areas of petroleum measurement.

  13. Texture Mapping via Optimal Mass Transport

    PubMed Central

    Dominitz, Ayelet; Tannenbaum, Allen

    2010-01-01

    In this paper, we present a novel method for texture mapping of closed surfaces. Our method is based on the technique of optimal mass transport (also known as the “earth-mover’s metric”). This is a classical problem that concerns determining the optimal way, in the sense of minimal transportation cost, of moving a pile of soil from one site to another. In our context, the resulting mapping is area preserving and minimizes angle distortion in the optimal mass sense. Indeed, we first begin with an angle-preserving mapping (which may greatly distort area) and then correct it using the mass transport procedure derived via a certain gradient flow. In order to obtain fast convergence to the optimal mapping, we incorporate a multiresolution scheme into our flow. We also use ideas from discrete exterior calculus in our computations. PMID:20224137

  14. Controlling Mass Transport in Microfluidic Devices

    NASA Astrophysics Data System (ADS)

    Kuo, Jason S.; Chiu, Daniel T.

    2011-07-01

    Microfluidic platforms offer exquisite capabilities in controlling mass transport for biological studies. In this review, we focus on recent developments in manipulating chemical concentrations at the microscale. Some techniques prevent or accelerate mixing, whereas others shape the concentration gradients of chemical and biological molecules. We also highlight several in vitro biological studies in the areas of organ engineering, cancer, and blood coagulation that have benefited from accurate control of mass transfer.

  15. Oceanic mass transport by mesoscale eddies.

    PubMed

    Zhang, Zhengguang; Wang, Wei; Qiu, Bo

    2014-07-18

    Oceanic transports of heat, salt, fresh water, dissolved CO2, and other tracers regulate global climate change and the distribution of natural marine resources. The time-mean ocean circulation transports fluid as a conveyor belt, but fluid parcels can also be trapped and transported discretely by migrating mesoscale eddies. By combining available satellite altimetry and Argo profiling float data, we showed that the eddy-induced zonal mass transport can reach a total meridionally integrated value of up to 30 to 40 sverdrups (Sv) (1 Sv = 10(6) cubic meters per second), and it occurs mainly in subtropical regions, where the background flows are weak. This transport is comparable in magnitude to that of the large-scale wind- and thermohaline-driven circulation. PMID:25035491

  16. Oceanic mass transport by mesoscale eddies.

    PubMed

    Zhang, Zhengguang; Wang, Wei; Qiu, Bo

    2014-07-18

    Oceanic transports of heat, salt, fresh water, dissolved CO2, and other tracers regulate global climate change and the distribution of natural marine resources. The time-mean ocean circulation transports fluid as a conveyor belt, but fluid parcels can also be trapped and transported discretely by migrating mesoscale eddies. By combining available satellite altimetry and Argo profiling float data, we showed that the eddy-induced zonal mass transport can reach a total meridionally integrated value of up to 30 to 40 sverdrups (Sv) (1 Sv = 10(6) cubic meters per second), and it occurs mainly in subtropical regions, where the background flows are weak. This transport is comparable in magnitude to that of the large-scale wind- and thermohaline-driven circulation.

  17. Efficient mass transport by optical advection

    PubMed Central

    Kajorndejnukul, Veerachart; Sukhov, Sergey; Dogariu, Aristide

    2015-01-01

    Advection is critical for efficient mass transport. For instance, bare diffusion cannot explain the spatial and temporal scales of some of the cellular processes. The regulation of intracellular functions is strongly influenced by the transport of mass at low Reynolds numbers where viscous drag dominates inertia. Mimicking the efficacy and specificity of the cellular machinery has been a long time pursuit and, due to inherent flexibility, optical manipulation is of particular interest. However, optical forces are relatively small and cannot significantly modify diffusion properties. Here we show that the effectiveness of microparticle transport can be dramatically enhanced by recycling the optical energy through an effective optical advection process. We demonstrate theoretically and experimentally that this new advection mechanism permits an efficient control of collective and directional mass transport in colloidal systems. The cooperative long-range interaction between large numbers of particles can be optically manipulated to create complex flow patterns, enabling efficient and tunable transport in microfluidic lab-on-chip platforms. PMID:26440069

  18. Quality of mass-reared codling moth (Lepidoptera: Tortricidae) after long-distance transportation: 1. Logistics of shipping procedures and quality parameters as measured in the laboratory.

    PubMed

    Blomefield, T; Carpenter, J E; Vreysen, M J B

    2011-06-01

    The sterile insect technique (SIT) is a proven effective control tactic against lepidopteran pests when applied in an areawide integrated pest management program. The construction of insect mass-rearing facilities requires considerable investment and moth control strategies that include the use of sterile insects could be made more cost-effective through the importation of sterile moths produced in other production centers. For codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), this is an attractive option because mating studies have confirmed the absence of mating barriers between codling moth populations from geographically different areas. To assess the feasibility of long-distance transportation of codling moths, pupae and adult moths were transported in 2004 from Canada to South Africa in four shipments by using normal commercial transport routes. The total transport time remained below 67 h in three of the consignments, but it was 89 h in the fourth consignment. Temperature in the shipping boxes was fairly constant and remained between -0.61 and 0.16 degrees C for 76.8-85.7% of the time. The data presented indicate that transporting codling moths as adults and pupae from Canada to South Africa had little effect on moth emergence, longevity, and ability to mate, as assessed in the laboratory. These results provide support to the suggestion that the STT for codling moth in pome fruit production areas might be evaluated and implemented by the importation of irradiated moths from rearing facilities in a different country or hemisphere.

  19. Delft Mass Transport model DMT-2

    NASA Astrophysics Data System (ADS)

    Ditmar, Pavel; Hashemi Farahani, Hassan; Inacio, Pedro; Klees, Roland; Zhao, Qile; Guo, Jing; Liu, Xianglin; Sun, Yu; Riva, Ricardo; Ran, Jiangjun

    2013-04-01

    Gravity Recovery And Climate Experiment (GRACE) satellite mission has enormously extended our knowledge of the Earth's system by allowing natural mass transport of various origin to be quantified. This concerns, in particular, the depletion and replenishment of continental water stocks; shrinking of polar ice sheets; deformation of the Earth's crust triggered by large earthquakes, and isostatic adjustment processes. A number of research centers compute models of temporal gravity field variations and mass transport, using GRACE data as input. One of such models - Delft Mass Transport model - is being produced at the Delft University of Technology in collaboration with the GNSS Research Center of Wuhan University. A new release of this model, DMT-2, has been produced on the basis of a new (second) release of GRACE level-1b data. This model consists of a time-series of monthly solutions spanning a time interval of more than 8 years, starting from Feb. 2003. Each solution consists of spherical harmonic coefficients up to degree 120. Both unconstrained and optimally filtered solutions are obtained. The most essential improvements of the DMT-2 model, as compared to its predecessors (DMT-1 and DMT-1b), are as follows: (i) improved estimation and elimination of low-frequency noise in GRACE data, so that strong mass transport signals are not damped; (ii) computation of accurate stochastic models of data noise for each month individually with a subsequent application of frequency-dependent data weighting, which allows statistically optimal solutions to be compiled even if data noise is colored and gradually changes in time; (iii) optimized estimation of accelerometer calibration parameters; (iv) incorporation of degree 1 coefficients estimated with independent techniques; (v) usage of state-of-the-art background models to de-alias GRACE data from rapid mass transport signals (this includes the EOT11a model of ocean tides and the latest release of the AOD1B product describing

  20. Mass transport enhancement in modified supercritical fluid

    SciTech Connect

    Abaroudi, K.; Trabelsi, F.; Calloud-Gabriel, B.; Recasens, F.

    1999-09-01

    In this paper, the supercritical-fluid extraction (SCFE) of a packed bed of {beta}-naphthol-impregnated porous pellets was studied. An increasing number of industrial SCFE processes involve the extraction of a solute retained within a porous matrix, usually in the form of seeds or irregular grains. The interest in high-pressure extraction is due to certain advantages of dense gases and near-critical solvents over conventional liquid solvents. In this study, modified carbon dioxide was the fluid studied. The effects of temperature, pressure, fluid velocity, particle size, and gravity were experimentally studied using carbon dioxide, pure or mixed with varying amounts of toluene (6%, and 10%). For the solute, {beta}-naphthol, the solubilities in SC carbon dioxide mixtures (from 0 to 10% toluene) were available from separate experiments. The dispersed plug-flow model was used to describe the nonideal flow. Fitting the experimental data with the model solution allowed the measurements of the fluid-to-particle mass transfer coefficient, the intraparticle diffusivity, and the axial dispersion coefficient (the latter in terms of the axial Peclet number). The influence of cosolvent concentration on the three transport parameters, which were not available so far, is presented.

  1. Mass and Momentum Turbulent Transport Experiments with Confined Coaxial Jets

    NASA Technical Reports Server (NTRS)

    Johnson, B. V.; Bennett, J. C.

    1981-01-01

    Downstream mixing of coaxial jets discharging in an expanded duct was studied to obtain data for the evaluation and improvement of turbulent transport models currently used in a variety of computational procedures throughout the propulsion community for combustor flow modeling. Flow visualization studies showed four major shear regions occurring; a wake region immediately downstream of the inlet jet inlet duct; a shear region further downstream between the inner and annular jets; a recirculation zone; and a reattachment zone. A combination of turbulent momentum transport rate and two velocity component data were obtained from simultaneous measurements with a two color laser velocimeter (LV) system. Axial, radial and azimuthal velocities and turbulent momentum transport rate measurements in the r-z and r-theta planes were used to determine the mean value, second central moment (or rms fluctuation from mean), skewness and kurtosis for each data set probability density function (p.d.f.). A combination of turbulent mass transport rate, concentration and velocity data were obtained system. Velocity and mass transport in all three directions as well as concentration distributions were used to obtain the mean, second central moments, skewness and kurtosis for each p.d.f. These LV/LIF measurements also exposed the existence of a large region of countergradient turbulent axial mass transport in the region where the annular jet fluid was accelerating the inner jet fluid.

  2. Transportation control measure information documents

    SciTech Connect

    Not Available

    1992-03-01

    The document, sponsored by the United States Environmental Protection Agency, is intended to provide information on Transportation Control Measures (TCMs) to transportation planning and air quality planning management and staff at all government levels. The document provides descriptions and examples of the TCMs listed in Section 108(f) of the Clean Air Act. Each TCM is described in terms of its objectives, variation in the ways it may be applied, expected transportation and emissions impacts, and other important implementation and policy considerations that State, regional, and local decision-making agencies will face.

  3. Precision Mass Measurements at CARIBU

    NASA Astrophysics Data System (ADS)

    Lascar, D.; van Schelt, J.; Savard, G.; Caldwell, S.; Chaudhuri, A.; Clark, J. A.; Levand, A. F.; Li, G.; Sternberg, M.; Sun, T.; Zabransky, B. J.; Segel, R.; Sharma, K.

    2010-02-01

    Neutron separation energies (Sn) are essential inputs to models of explosive r-process nucleosynthesis. However, for nuclei farther from stability, the precision of Sn decreases as production decreases and observation of those nuclei become more difficult. Many of the most critical inputs to the models are based on extrapolations from measurements of masses closer to stability than the predicted r-process path. Measuring masses that approach and lie on the predicted r-process path will further constrain the systematic uncertainties in these extrapolated values. The Canadian Penning Trap Mass Spectrometer (CPT) at Argonne National Laboratory (ANL) has measured the masses of more than 160 nuclei to high precision. A recent move to the CAlifornium Rare Isotope Breeder Upgrade (CARIBU) at ANL has given the CPT unique access to weakly produced nuclei that cannot be easily reached via proton induced fission of ^238U. CARIBU will eventually use a 1 Ci source of ^252Cf to produce these nuclei. Installation of the CPT at CARIBU as well as the first CPT mass measurements of neutron rich nuclei at CARIBU will be discussed. )

  4. Mass Transport Through Carbon Nanotube-Polystyrene Bundles

    NASA Astrophysics Data System (ADS)

    Lin, Rongzhou; Tran, Tuan

    2016-05-01

    Carbon nanotubes have been widely used as test channels to study nanofluidic transport, which has been found to have distinctive properties compared to transport of fluids in macroscopic channels. A long-standing challenge in the study of mass transport through carbon nanotubes (CNTs) is the determination of flow enhancement. Various experimental investigations have been conducted to measure the flow rate through CNTs, mainly based on either vertically aligned CNT membranes or individual CNTs. Here, we proposed an alternative approach that can be used to quantify the mass transport through CNTs. This is a simple method relying on the use of carbon nanotube-polystyrene bundles, which are made of CNTs pulled out from a vertically aligned CNT array and glued together by polystyrene. We experimentally showed by using fluorescent tagging that the composite bundles allowed measureable and selective mass transport through CNTs. This type of composite bundle may be useful in various CNT research areas as they are simple to fabricate, less likely to form macroscopic cracks, and offer a high density of CNT pores while maintaining the aligned morphology of CNTs.

  5. Energy and mass transport in the thermosphere

    NASA Technical Reports Server (NTRS)

    Mayr, H. G.; Harris, I.; Spencer, N. W.

    1979-01-01

    Examples illustrating the effects of large scale energy and mass transport in the thermosphere discussed include: (1) The seasonal variations reveal temperature, composition, and ionospheric anomalies involving energy exchange between the thermosphere and mesosphere. (2) The midnight temperature maximum in the thermosphere is interpreted as a signature of tidal waves emanating from the mesosphere and momentum coupling associated with ion drag. (3) The ionospheric storm in the F region illustrates the intricate effects of large scale atmospheric winds driven by magnetospheric energization processes. (4) Atmospheric signatures of Joule heating and electric field momentum coupling are markedly different.

  6. Mass transport in annular spherical system

    NASA Astrophysics Data System (ADS)

    Bauer, Helmut F.

    The mass transport between two concentric spheres with inlet and outlet at the poles was determined for ideal liquid flow (plug flow) and laminar flow for constant concentration at the spherical walls and constant concentration at the inlet. Velocity distribution and local concentration profiles were determined analytically for various widths of the annular spherical conduit and various diffusive flow parameters. It is found that with the increase of this parameter, the decay becomes quite rapid and that the same effect occurs for increasing diameter ratio of the spheres. This configuration may possibly be used as a basic element of an artificial kidney.

  7. Top Mass Measurement at CDF

    SciTech Connect

    Kordas, Kostas; /Frascati

    2006-03-01

    We report on recent measurements of the top quark mass using t{bar t} candidate events selected in {approx_equal} 320 pb{sup -1} of data from the ''Run II'' operation period of the Tevatron p{bar p} collider. More emphasis is given on the best single measurement to date (M{sub top} = 173.5{sub -3.8}{sup +3.9} GeV/c{sup 2}), provided by CDF using the ''lepton plus jets'' channel, where one W decays to a lepton-neutrino pair and the other into quarks (top quarks decay to Wb almost 100% of the time).

  8. Mass transfer and transport in salt repositories

    SciTech Connect

    Pigford, T.H.; Chambre, P.L.; Lee, W.W.L.

    1989-02-01

    Salt is a unique rock isolation of nuclear waste because it is dry'' and nearly impermeable. In this paper we summarize some mass-transfer and transport analyses of salt repositories. First we analyses brine migration. Heating by high-level waste can cause brine in grain boundaries to move due to pressure-gradients. We analyze brine migration treating salt as a thermoelastic solid and found that brine migration is transient and localized. We use previously developed techniques to estimate release rates from waste packages by diffusion. Interbeds exist in salt and may be conduits for radionuclide migration. We analyze steady-state migration due to brine flow in the interbed, as a function of the Peclet number. Then we analyze transient mass transfer, both into the interbed and directly to salt, due only to diffusion. Finally we compare mass transfer rates of a waste cylinder in granite facing a fracture and in salt facing an interbed. In all cases, numerical illustrations of the analytic solution are given. 10 refs., 4 figs., 3 tabs.

  9. Online volatile organic compound measurements using a newly developed proton-transfer ion-trap mass spectrometry instrument during New England Air Quality Study--Intercontinental Transport and Chemical Transformation 2004: performance, intercomparison, and compound identification.

    PubMed

    Warneke, Carsten; Kato, Shuji; De Gouw, Joost A; Goldan, Paul D; Kuster, William C; Shao, Min; Lovejoy, Edward R; Fall, Ray; Fehsenfeld, Fred C

    2005-07-15

    We have used a newly developed proton-transfer ion-trap mass spectrometry (PIT-MS) instrument for online trace gas analysis of volatile organic compounds (VOCs) during the 2004 New England Air Quality Study-Intercontinental Transport and Chemical Transformation study. The PIT-MS instrument uses proton-transfer reactions with H3O+ ions to ionize VOCs, similarto a PTR-MS (proton-transfer reaction mass spectrometry) instrument but uses an ion trap mass spectrometer to analyze the product ions. The advantages of an ion trap are the improved identification of VOCs and a near 100% duty cycle. During the experiment, the PIT-MS instrument had a detection limit between 0.05 and 0.3 pbbv (S/N = 3 (signal-to-noise ratio)) for 2-min integration time for most tested VOCs. PIT-MS was used for ambient air measurements onboard a research ship and agreed well with a gas chromatography mass spectrometer). The comparison included oxygenated VOCs, aromatic compounds, and others such as isoprene, monoterpenes, acetonitrile, and dimethyl sulfide. Automated collision-induced dissociation measurements were used to determine the contributions of acetone and propanal to the measured signal at 59 amu; both species are detected at this mass and are thus indistinguishable in conventional PTR-MS.

  10. Optimal Mass Transport for Shape Matching and Comparison

    PubMed Central

    Su, Zhengyu; Wang, Yalin; Shi, Rui; Zeng, Wei; Sun, Jian; Luo, Feng; Gu, Xianfeng

    2015-01-01

    Surface based 3D shape analysis plays a fundamental role in computer vision and medical imaging. This work proposes to use optimal mass transport map for shape matching and comparison, focusing on two important applications including surface registration and shape space. The computation of the optimal mass transport map is based on Monge-Brenier theory, in comparison to the conventional method based on Monge-Kantorovich theory, this method significantly improves the efficiency by reducing computational complexity from O(n2) to O(n). For surface registration problem, one commonly used approach is to use conformal map to convert the shapes into some canonical space. Although conformal mappings have small angle distortions, they may introduce large area distortions which are likely to cause numerical instability thus resulting failures of shape analysis. This work proposes to compose the conformal map with the optimal mass transport map to get the unique area-preserving map, which is intrinsic to the Riemannian metric, unique, and diffeomorphic. For shape space study, this work introduces a novel Riemannian framework, Conformal Wasserstein Shape Space, by combing conformal geometry and optimal mass transport theory. In our work, all metric surfaces with the disk topology are mapped to the unit planar disk by a conformal mapping, which pushes the area element on the surface to a probability measure on the disk. The optimal mass transport provides a map from the shape space of all topological disks with metrics to the Wasserstein space of the disk and the pullback Wasserstein metric equips the shape space with a Riemannian metric. We validate our work by numerous experiments and comparisons with prior approaches and the experimental results demonstrate the efficiency and efficacy of our proposed approach. PMID:26440265

  11. MASS TRANSPORT EFFECTS ON THE KINETICS OF NITROBENZENE REDUCTION BY IRON METAL. (R827117)

    EPA Science Inventory

    To evaluate the importance of external mass transport on the overall rates of
    contaminant reduction by iron metal (Fe0), we have compared measured
    rates of surface reaction for nitrobenzene (ArNO2) to estimated rates
    of external mass transport...

  12. Sediment transport measurements: Chapter 5

    USGS Publications Warehouse

    Diplas, P.; Kuhnle, R.; Gray, J.; Glysson, D.; Edwards, T.; García, Marcelo H.

    2008-01-01

    Sediment erosion, transport, and deposition in fluvial systems are complex processes that are treated in detail in other sections of this book. Development of methods suitable for the collection of data that contribute to understanding these processes is a still-evolving science. Sediment and ancillary data are fundamental requirements for the proper management of river systems, including the design of structures, the determination of aspects of stream behavior, ascertaining the probable effect of removing an existing structure, estimation of bulk erosion, transport, and sediment delivery to the oceans, ascertaining the long-term usefulness of reservoirs and other public works, tracking movement of solid-phase contaminants, restoration of degraded or otherwise modified streams, and assistance in the calibration and validation of numerical models. This chapter presents techniques for measuring bed-material properties and suspended and bed-load discharges. Well-established and relatively recent, yet adequately tested, sampling equipment and methodologies, with designs that are guided by sound physical and statistical principles, are described. Where appropriate, the theory behind the development of the equipment and guidelines for its use are presented.

  13. Facilitating Precision Mass Measurements at CARIBU

    NASA Astrophysics Data System (ADS)

    Lascar, Daniel; van Schelt, Jon; Savard, Guy; Segel, Ralph; Clark, Jason; Sharma, Kumar; Caldwell, Shane; Gang, Li; Sternberg, Matthew; Greene, John; Levand, Anthony; Zabransky, Bruce

    2011-10-01

    The Canadian Penning Trap Mass Spectrometer (CPT) has begun a campaign of precision mass measurements of neutron-rich nuclei produced via spontaneous fission of 252Cf as part of the CAlifornium Rare Isotope Breeder Upgrade (CARIBU) to the ATLAS facility at Argonne National Laboratory. As of the time of submission of this abstract, we have measured neutron rich isotopes of Cs, I, Te, Sb, and Sn. CARIBU is currently running with a 60 mCi source of 252Cf which will be upgraded to a 1 Ci source in the future. In order to make this campaign possible, several upgrades to the CARIBU and CPT system were required including a new Radio Frequency Quadrupole (RFQ) ion buncher to CARIBU's low energy beamline, cryogenic cooling of the RFQ Paul trap below the CPT, and an electrostatic elevator to allow for transport of ion bunches from a 50 kV platform to the CPT system's 2 kV beamline. Construction and commissioning of the buncher and modified Paul Trap will be discussed as well as their impact on the measurements in this campaign. Support from U.S. DOE, Nucl Phys Div and NSERC Canada.

  14. Hydrologic and geochemical controls on the transport of radionuclides in natural undisturbed arid environments as determined by accelerator mass spectrometry measurements

    SciTech Connect

    Nimz, G; Caffee, M W; McAninch, J

    2000-04-01

    This project developed techniques for measuring globally distributed radionuclides that occur today in extremely low abundances (''fallout'' from the era of atmospheric nuclear testing), and then applied these techniques to better understand the mechanisms by which radionuclides migrate. The techniques employ accelerator mass spectrometry (AMS), a relatively new analytical tool that permits this work to be conducted for the first time. The goal in this project was to develop AMS analytical techniques for {sup 129}I (fallout concentration: {approx} 10{sup 6} atoms/g) {sup 99}Tc ({approx} 10{sup 9} atoms/g), {sup 90}Sr ({approx}10{sup 7} atoms/gram soil), and {sup 93}Zr ({approx} 10{sup 9} atoms/g), and improved methods for {sup 36}Cl ({approx} 10{sup 9} atoms/g). As a demonstration of the analytical techniques, and as an investigation of identified problems associated with characterizing moisture and radionuclide movement in unsaturated desert soils, we developed a vadose zone research site at the Nevada Test Site. Our findings can be summarized as follows: (1) The distribution of chloride and {sup 36}Cl at the research site indicates that the widely-used ''chloride accumulation'' method for estimating moisture flux is erroneous; some mechanism for attenuation of chloride exists, violating an assumption of the accumulation method; (2) {sup 129}I is fractionated into several soil compartments that have varying migration abilities; the two most mobile can be tentatively identified as Fe/Mn oxyhydroxides and organic acids based on our sequential leaching techniques; (3) These most mobile constituents are capable of migrating at a rate greater than that of {sup 36}Cl, usually considered the most mobile solute in hydrologic systems; these constituents may be colloidal in character, of neutral surface charge, and therefore conservative in aqueous migration; (4) {sup 99}Tc is readily measurable by AMS, as we demonstrate by the first AMS {sup 99}Tc measurements of

  15. Mass Flux of ZnSe by Physical Vapor Transport

    NASA Technical Reports Server (NTRS)

    Sha, Yi-Gao; Su, Ching-Hua; Palosz, W.; Volz, M. P.; Gillies, D. C.; Szofran, F. R.; Lehoczky, S. L.; Liu, Hao-Chieh; Brebrick, R. F.

    1995-01-01

    Mass fluxes of ZnSe by physical vapor transport (PVT) were measured in the temperature range of 1050 to 1160 C using an in-situ dynamic technique. The starting materials were either baked out or distilled under vacuum to obtain near-congruently subliming compositions. Using an optical absorption technique Zn and Se, were found to be the dominant vapor species. Partial pressures of Zn and Se, over the starting materials at temperatures between 960 and 1140 C were obtained by measuring the optical densities of the vapor phase at the wavelengths of 2138, 3405, 3508, 3613, and 3792 A. The amount and composition of the residual gas inside the experimental ampoules were measured after the run using a total pressure gauge. For the first time, the experimentally determined partial pressures of Zn and Se, and the amount and composition of the residual gas were used in a one-dimensional diffusion limited analysis of the mass transport rates for a PVT system. Reasonable agreement between the experimental and theoretical results was observed.

  16. Thermal /Soret/ diffusion effects on interfacial mass transport rates

    NASA Technical Reports Server (NTRS)

    Rosner, D. E.

    1980-01-01

    It is shown that thermal (Soret) diffusion significantly alters convective mass transport rates and important transition temperatures in highly nonisothermal flow systems involving the transport of 'heavy' species (vapors or particles). Introduction of the Soret transport term is shown to result in mass transfer effects similar to those of 'suction' and a homogeneous chemical 'sink'. It is pointed out that this analogy provides a simple method of correlating and predicting thermal diffusion effects in the abovementioned systems.

  17. Measurement of adherent cell mass and growth

    PubMed Central

    Park, Kidong; Millet, Larry J.; Kim, Namjung; Li, Huan; Jin, Xiaozhong; Popescu, Gabriel; Aluru, N. R.; Hsia, K. Jimmy; Bashir, Rashid

    2010-01-01

    The characterization of physical properties of cells such as their mass and stiffness has been of great interest and can have profound implications in cell biology, tissue engineering, cancer, and disease research. For example, the direct dependence of cell growth rate on cell mass for individual adherent human cells can elucidate the mechanisms underlying cell cycle progression. Here we develop an array of micro-electro-mechanical systems (MEMS) resonant mass sensors that can be used to directly measure the biophysical properties, mass, and growth rate of single adherent cells. Unlike conventional cantilever mass sensors, our sensors retain a uniform mass sensitivity over the cell attachment surface. By measuring the frequency shift of the mass sensors with growing (soft) cells and fixed (stiff) cells, and through analytical modeling, we derive the Young’s modulus of the unfixed cell and unravel the dependence of the cell mass measurement on cell stiffness. Finally, we grew individual cells on the mass sensors and measured their mass for 50+ hours. Our results demonstrate that adherent human colon epithelial cells have increased growth rates with a larger cell mass, and the average growth rate increases linearly with the cell mass, at 3.25%/hr. Our sensitive mass sensors with a position-independent mass sensitivity can be coupled with microscopy for simultaneous monitoring of cell growth and status, and provide an ideal method to study cell growth, cell cycle progression, differentiation, and apoptosis. PMID:21068372

  18. Quality of mass-reared codling moth (Lepidoptera: Tortricidae) after long distance transportation 1. Logistics of shipping procedures and quality parameters as measured in the laboratory.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The sterile insect technique is a proven effective control tactic against lepidopteran pests when applied in an area-wide integrated pest management programme. The construction of insect mass-rearing facilities requires considerable investment and moth control strategies that include the use of ster...

  19. Effects of solution mass transport on the ECC ozonesonde background current. [Electrochemical Concentration Cell

    NASA Technical Reports Server (NTRS)

    Thornton, D. C.; Niazy, N.

    1983-01-01

    A technique is developed to measure the effective mass transport parameter for the electrochemical concentration cell (ECC) ozonesonde in order to determine the mass transport rate constant for the ECC as a function of pressure. It is shown that a pressure dependent factor in the background current originates in a convective mass transport parameter. It is determined that for atmospheric pressures greater than 100 mb the mass transport parameter is a constant, while at pressures less than 100 mb it decreases logarithmically with pressure. It is suggested that the background current correction is directly correlated to the mass transport parameter pressure dependence. The presently used background current correction, which is based on the partial pressure of oxygen, is found to lead to an overestimation of the integrated ozone value in the troposphere for the ECC ozonesonde data.

  20. Accurate Mass Measurements in Proteomics

    SciTech Connect

    Liu, Tao; Belov, Mikhail E.; Jaitly, Navdeep; Qian, Weijun; Smith, Richard D.

    2007-08-01

    To understand different aspects of life at the molecular level, one would think that ideally all components of specific processes should be individually isolated and studied in details. Reductionist approaches, i.e., studying one biological event at a one-gene or one-protein-at-a-time basis, indeed have made significant contributions to our understanding of many basic facts of biology. However, these individual “building blocks” can not be visualized as a comprehensive “model” of the life of cells, tissues, and organisms, without using more integrative approaches.1,2 For example, the emerging field of “systems biology” aims to quantify all of the components of a biological system to assess their interactions and to integrate diverse types of information obtainable from this system into models that could explain and predict behaviors.3-6 Recent breakthroughs in genomics, proteomics, and bioinformatics are making this daunting task a reality.7-14 Proteomics, the systematic study of the entire complement of proteins expressed by an organism, tissue, or cell under a specific set of conditions at a specific time (i.e., the proteome), has become an essential enabling component of systems biology. While the genome of an organism may be considered static over short timescales, the expression of that genome as the actual gene products (i.e., mRNAs and proteins) is a dynamic event that is constantly changing due to the influence of environmental and physiological conditions. Exclusive monitoring of the transcriptomes can be carried out using high-throughput cDNA microarray analysis,15-17 however the measured mRNA levels do not necessarily correlate strongly with the corresponding abundances of proteins,18-20 The actual amount of functional proteins can be altered significantly and become independent of mRNA levels as a result of post-translational modifications (PTMs),21 alternative splicing,22,23 and protein turnover.24,25 Moreover, the functions of expressed

  1. Mass measurements with a Penning trap mass spectrometer at ISOLDE

    SciTech Connect

    Bollen, G.; Ames, F.; Schark, E.; Audi, G.; Lunney, D.; Saint Simon, M. de; Beck, D.; Herfurth, F.; Kluge, H.-J.; Kohl, A.; Schwarz, S.; Moore, R. B.; Szerypo, J.

    1998-12-21

    Penning trap mass measurements on radioactive isotopes are performed with the ISOLTRAP mass spectrometer at ISOLDE/CERN. In the last years the applicability of the spectrometer has been considerably extended. The most recent measurements were carried out on isotopes of rare earth elements and on isotopes with Z=80-85. An accuracy of {delta}m/m{approx_equal}1{center_dot}10{sup -7} was achieved.

  2. Top Mass Measurements at the Tevatron

    SciTech Connect

    Wang, M.H.L.S.; /Fermilab

    2009-04-01

    We present the latest measurements of the top quark mass from the Tevatron. The different top decay channels and measurement techniques used for these results are also described. The world average of the top quark mass based on some of these new results combined with previous results is m{sub top} = 172.6 {+-} 1.4 GeV.

  3. Angular momentum transport within evolved low-mass stars

    SciTech Connect

    Cantiello, Matteo; Bildsten, Lars; Paxton, Bill; Mankovich, Christopher; Christensen-Dalsgaard, Jørgen

    2014-06-10

    Asteroseismology of 1.0-2.0 M {sub ☉} red giants by the Kepler satellite has enabled the first definitive measurements of interior rotation in both first ascent red giant branch (RGB) stars and those on the helium burning clump. The inferred rotation rates are 10-30 days for the ≈0.2 M {sub ☉} He degenerate cores on the RGB and 30-100 days for the He burning core in a clump star. Using the Modules for Experiments in Stellar Evolution code, we calculate state-of-the-art stellar evolution models of low mass rotating stars from the zero-age main sequence to the cooling white dwarf (WD) stage. We include transport of angular momentum due to rotationally induced instabilities and circulations, as well as magnetic fields in radiative zones (generated by the Tayler-Spruit dynamo). We find that all models fail to predict core rotation as slow as observed on the RGB and during core He burning, implying that an unmodeled angular momentum transport process must be operating on the early RGB of low mass stars. Later evolution of the star from the He burning clump to the cooling WD phase appears to be at nearly constant core angular momentum. We also incorporate the adiabatic pulsation code, ADIPLS, to explicitly highlight this shortfall when applied to a specific Kepler asteroseismic target, KIC8366239.

  4. Pediatric and neonatal interfacility transport medicine after mass casualty incidents.

    PubMed

    Lowe, Calvin G

    2009-08-01

    Pediatric and neonatal interfacility transport medicine is a relatively young but a rapidly evolving specialty. Transport teams are essential for the safe interfacility movement of critically ill patients. A mass casualty incident (MCI) can present major challenges for a critical care transport team. This article will examine the capabilities and limitations of pediatric and neonatal critical care transport teams. The predicaments brought about by Hurricane Katrina that hindered the evacuation of pediatric and neonatal patients out of ravaged hospitals are also reviewed. From these experiences, recommendations to improve the efficiency and efficacy of interfacility transport of pediatric patients will be presented.

  5. Mass transport by mode-2 internal solitary-like waves

    NASA Astrophysics Data System (ADS)

    Deepwell, David; Stastna, Marek

    2016-05-01

    We present the first three-dimensional numerical simulations of the mass transport capabilities of mode-2 waves formed by a lock-release mechanism with both single and double pycnocline stratifications. Single pycnoclines and double pycnoclines with a small spacing between the pycnocline centres were found to exhibit large Lee instabilities which formed during the collapse of the intermediate density region. These instabilities led to the generation of vorticity dipoles across the mid-depth, and thereby contributed to the reduction in the mass transported by the wave. A double pycnocline with a separation of approximately 12% of the depth between the two pycnocline centres was found to transport a passive tracer optimally for the longest time-period. Increasing Schmidt number correlated with increasing mass transport, while decreasing the tracer diffusivity led to increasing mass transport, but only when a trapped core existed. Contrasted two-dimensional simulations reveal that in certain cases, most noticeably the optimal transport case, the mass transport is significantly different from the corresponding three-dimensional simulation.

  6. Precise atomic mass measurements by deflection mass spectrometry

    NASA Astrophysics Data System (ADS)

    Barber, R. C.; Sharma, K. S.

    2003-05-01

    Since its inception nearly 90 years ago by J.J. Thomson, the precise determination of atomic masses by the classical technique of deflecting charged particles in electric and magnetic fields has provided a large body of data on naturally occurring nuclides. Currently, such measurements on stable nuclides have frequently achieved a precision of better than two parts in 10 9 of the mass. A review of the technique, together with a brief summary of the important historical developments in the field of precise atomic mass measurements, will be given. The more recent contributions to this field by the deflection mass spectrometer at the University of Manitoba will be provided as illustrations of the culmination of the techniques used and the applications that have been studied. A brief comparison between this and newer techniques using Penning traps will be presented.

  7. Measuring the Masses of Ophiuchus Binaries

    NASA Astrophysics Data System (ADS)

    Schaefer, Gail

    2014-02-01

    Our goal is to measure dynamical masses of low-mass (<1 Msun) young (<5 Myr) binary components. We propose to continue mapping the orbits of young pairs using AO imaging. Combined with high-resolution spectroscopy, this will yield mass precisions of <5. This is important to validate and distinguish among theoretical calculations of young star evolution, which are most discrepant for low-mass stars. We target 22 binaries in Ophiuchus with unmapped orbits and 1 binary for which additional astrometry will yield precision values for its masses and distance. We request two half-nights, with LGS and NGS AO using NIRC2 on Keck II.

  8. Mass measurements of exotic nuclides at SHIPTRAP

    SciTech Connect

    Block, M.; Ackermann, D.; Eliseev, S.; Herfurth, F.; Hessberger, F. P.; Hofmann, S.; Kluge, H.-J.; Maero, G.; Martin, A.; Mazzocco, M.; Mukherjee, M.; Quint, W.; Rahaman, S.; Rauth, C.; Rodriguez, D.; Scheidenberger, C.; Vorobjev, G.; Blaum, K.; Ferrer, R.; Weber, C.

    2007-05-22

    The Penning trap mass spectrometer SHIPTRAP is installed behind the velocity-filter SHIP at GSI for high-precision mass measurements of fusion-evaporation residues. To facilitate an efficient stopping of the reaction products a buffer gas stopping cell is utilized. In an investigation of neutron-deficient nuclides in the terbium-to-thulium region around A {approx_equal} 146, 18 new or improved mass values have been obtained, resulting in a more accurate determination of the proton drip line for holmium and thulium. With the present performance of SHIPTRAP, a first direct mass measurement of transuranium elements in the nobelium region is within reach.

  9. Mass Transportation Operators' Beliefs about Visual Impairment.

    ERIC Educational Resources Information Center

    Almon, Pamela A.

    2001-01-01

    A study investigated 171 mass transit operators' beliefs about blindness and the factors that may influence their beliefs. There were statistically significant differences among transit operators' beliefs on the basis of the operators' ethnicity. White participants had significantly fewer irrational beliefs about blindness than Hispanic and…

  10. Neutrino mass measurement from correlation dipoles

    NASA Astrophysics Data System (ADS)

    Chen, Xuelei

    2015-08-01

    The large scale structure measurement can be used as a precision probe for neutrinos. It is well known that the power spectrum is suppressed at relatively small scales by the free-streaming of neutrinos, and this is used to measure the neutrino mass. However, this method is prone to scale-dependent galaxy bias, which can lead to significant system error in the measurement. We proposed a new method to measure the neutrino mass which is free of this problem. Due to their smaller masses, the neutrinos can develop large relative velocities with respect to the dark matter, the neutrino distribution can then affect the structure formation process. Although the effect is very small, it may generate significant dipole in the galaxy cross-correlation function or the galaxy lensing. The neutrino mass may by determined by such observations. We present the feasibility for such measurement.

  11. Top quark mass measurement at the Tevatron

    SciTech Connect

    Guimaraes da Costa, Joao; /Harvard U.

    2004-12-01

    The authors report on the latest experimental measurements of the top quark mass by the CDF and D0 Collaborations at the Fermilab Tevatron. They present a new top mass measurement using the t{bar t} events collected by the D0 Collaboration in Run I between 1994 and 1996. This result is combined with previous measurements to yield a new world top mass average. They also describe several preliminary results using up to 193 pb{sup -1} of t{bar t} events produced in {bar p}p collisions at {radical}s = 1.96 TeV during the Run II of the Tevatron.

  12. Gas measurement using Coriolis mass flowmeters

    SciTech Connect

    Pawlas, G.; Patten, T.

    1995-12-31

    This paper demonstrates Coriolis mass flowmeters (CMF) can provide a solution for measuring the mass flowrate of gases directly, i.e. no knowledge of the gas properties is required. The test results for natural gas and compressed air presented here were obtained using a standard factory water calibration. This demonstrates properly designed CMF and linear devices and can provide accurate results independent of gas composition over wide pressure and mass flowrate ranges.

  13. Top quark mass measurements at CDF

    SciTech Connect

    Maki, Tuula; /Helsinki U. /Helsinki Inst. of Phys.

    2007-10-01

    The top quark mass is interesting both as a fundamental parameter of the standard model as well as an important input to precision electroweak tests. The CDF Collaboration has measured the top quark mass with high precision in all decay channels with complementary methods. A combination of the results from CDF gives a top quark mass of 170.5{+-}1.3(stat.){+-}1.8(syst.) GeV/c{sup 2}.

  14. Space Geodesy Monitoring Mass Transport in Global Geophysical Fluids

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

    Mass transports occurring in the atmosphere-hydrosphere-cryosphere-solid Earth-core system (the 'global geophysical fluids') are important geophysical phenomena. They occur on all temporal and spatial scales. Examples include air mass and ocean circulations, oceanic and solid tides, hydrological water and idsnow redistribution, mantle processes such as post-glacial rebound, earthquakes and tectonic motions, and core geodynamo activities. The temporal history and spatial pattern of such mass transport are often not amenable to direct observations. Space geodesy techniques, however, have proven to be an effective tool in monitorihg certain direct consequences of the mass transport, including Earth's rotation variations, gravitational field variations, and the geocenter motion. Considerable advances have been made in recent years in observing and understanding of these geodynamic effects. This paper will use several prominent examples to illustrate the triumphs in research over the past years under a 'Moore's law' in space geodesy. New space missions and projects promise to further advance our knowledge about the global mass transports. The latter contributes to our understanding of the geophysical processes that produce and regulate the mass transports, as well as of the solid Earth's response to such changes in terms of Earth's mechanical properties.

  15. Simplified fundamental force and mass measurements

    NASA Astrophysics Data System (ADS)

    Robinson, I. A.

    2016-08-01

    The watt balance relates force or mass to the Planck constant h, the metre and the second. It enables the forthcoming redefinition of the unit of mass within the SI by measuring the Planck constant in terms of mass, length and time with an uncertainty of better than 2 parts in 108. To achieve this, existing watt balances require complex and time-consuming alignment adjustments limiting their use to a few national metrology laboratories. This paper describes a simplified construction and operating principle for a watt balance which eliminates the need for the majority of these adjustments and is readily scalable using either electromagnetic or electrostatic actuators. It is hoped that this will encourage the more widespread use of the technique for a wide range of measurements of force or mass. For example: thrust measurements for space applications which would require only measurements of electrical quantities and velocity/displacement.

  16. Transportability of Deductive Measurement across Cultures.

    ERIC Educational Resources Information Center

    McCauley, Donald E., Jr.; Colberg, Magda

    1983-01-01

    A theory and test of cross-cultural transportability of measurement were constructed on a logico-mathematical basis regarding the deductive measures and on a basis of syntactic reduction and Latin-based vocabulary regarding the linguistic measuring medium. A pilot study was administered in Spain, France, and the United States. (Author/PN)

  17. Penning trap mass measurements on nobelium isotopes

    SciTech Connect

    Dworschak, M.; Block, M.; Ackermann, D.; Herfurth, F.; Hessberger, F. P.; Hofmann, S.; Vorobyev, G. K.; Audi, G.; Blaum, K.; Droese, C.; Marx, G.; Schweikhard, L.; Eliseev, S.; Ketter, J.; Fleckenstein, T.; Haettner, E.; Plass, W. R.; Scheidenberger, C.; Ketelaer, J.; Kluge, H.-J.

    2010-06-15

    The Penning trap mass spectrometer SHIPTRAP at GSI Darmstadt allows accurate mass measurements of radionuclides, produced in fusion-evaporation reactions and separated by the velocity filter SHIP from the primary beam. Recently, the masses of the three nobelium isotopes {sup 252-254}No were determined. These are the first direct mass measurements of transuranium elements, which provide new anchor points in this region. The heavy nuclides were produced in cold-fusion reactions by irradiating a PbS target with a {sup 48}Ca beam, resulting in production rates of the nuclei of interest of about one atom per second. In combination with data from decay spectroscopy our results are used to perform a new atomic-mass evaluation in this region.

  18. Penning trap mass measurements on nobelium isotopes

    NASA Astrophysics Data System (ADS)

    Dworschak, M.; Block, M.; Ackermann, D.; Audi, G.; Blaum, K.; Droese, C.; Eliseev, S.; Fleckenstein, T.; Haettner, E.; Herfurth, F.; Heßberger, F. P.; Hofmann, S.; Ketelaer, J.; Ketter, J.; Kluge, H.-J.; Marx, G.; Mazzocco, M.; Novikov, Yu. N.; Plaß, W. R.; Popeko, A.; Rahaman, S.; Rodríguez, D.; Scheidenberger, C.; Schweikhard, L.; Thirolf, P. G.; Vorobyev, G. K.; Wang, M.; Weber, C.

    2010-06-01

    The Penning trap mass spectrometer SHIPTRAP at GSI Darmstadt allows accurate mass measurements of radionuclides, produced in fusion-evaporation reactions and separated by the velocity filter SHIP from the primary beam. Recently, the masses of the three nobelium isotopes No252-254 were determined. These are the first direct mass measurements of transuranium elements, which provide new anchor points in this region. The heavy nuclides were produced in cold-fusion reactions by irradiating a PbS target with a Ca48 beam, resulting in production rates of the nuclei of interest of about one atom per second. In combination with data from decay spectroscopy our results are used to perform a new atomic-mass evaluation in this region.

  19. Mass transport limitation in implantable defibrillator batteries

    NASA Astrophysics Data System (ADS)

    Schmidt, C.; Tam, G.; Scott, E.; Norton, J.; Chen, K.

    Using cells with lithium reference electrodes, the power-limiting behavior in the lithium-SVO cell was shown to be due to a rapid voltage transition at the anode. A novel test cell was developed to explore the influence of current density, bulk LiAsF 6 concentration, separator type and separator proximity to the anode on the time to onset ( τ) of the anode polarization. The results were found to follow a relationship, iτ1/2∝ Cbulk, consistent with the Sand equation. This relationship also predicts that the critical concentration of LiAsF 6, at which onset of the anode polarization occurs, is near the solubility limit of LiAsF 6 in our system (around 3.5-4.0 M). This general phenomenon was found to be quantitatively similar for two dissimilar separator types, and the anode polarization could also be induced in the absence of separator at high concentration and current density. However, it appears that τ decreases with closer proximity of the separator to the anode surface (i.e. cell stack pressure), suggesting that the effect of separator is to inhibit convective transport to and from the Li surface.

  20. Frontiers in Cancer Nanomedicine: Directing Mass Transport through Biological Barriers

    PubMed Central

    Ferrari, Mauro

    2010-01-01

    The physics of mass transport within body compartments and across biological barriers differentiates cancers from healthy tissues. Variants of nanoparticles can be manufactured in combinatorially large sets, varying only one transport-affecting design parameter at a time. Nanoparticles can also be used as building blocks for systems that perform sequences of coordinated actions, in accordance to a prescribed logic. These are referred to as Logic-Embedded Vectors “(LEV)” in the following. Nanoparticles and LEVs are ideal probes for the determination of mass transport laws in tumors, acting as imaging contrast enhancers, and can be employed for the lesion-selective delivery of therapy. Their size, shape, density and surface chemistry dominate convective transport in the blood stream, margination, cell adhesion, selective cellular uptake, as well as sub-cellular trafficking and localization. As argued here, the understanding of transport differentials in cancer, termed ‘transport oncophysics’ unveils a new promising frontier in oncology: the development of lesion-specific delivery particulates that exploit mass transport differentials to deploy treatment of greater efficacy and reduced side effects. PMID:20079548

  1. Ratio method of measuring W boson mass

    SciTech Connect

    Guo, Feng

    2010-08-01

    This dissertation describes an alternative method of measuring the W boson mass in DØ experiment. Instead of extracting MW from the fitting of W → ev fast Monte Carlo simulations to W → ev data as in the standard method, we make the direct fit of transverse mass between W → ev data and Z → ee data. One of the two electrons from Z boson is treated as a neutrino in the calculation of transverse mass. In ratio method, the best fitted scale factor corresponds to the ratio of W and Z boson mass (MW/MZ). Given the precisely measured Z boson mass, W mass is directly fitted from W → ev and Z → ee data. This dissertation demonstrates that ratio method is a plausible method of measuring the W boson mass. With the 1 fb-1 DØ Run IIa dataset, ratio method gives MW = 80435 ± 43(stat) ± 26(sys) MeV.

  2. Mass transport in an anatomically realistic human right coronary artery.

    PubMed

    Kaazempur-Mofrad, M R; Ethier, C R

    2001-02-01

    The coronary arteries are a common site of atherosclerotic plaque formation, which has been putatively linked to hemodynamic and mass transport patterns. The purpose of this paper was to study mass transport patterns in a human right coronary artery (RCA) model, focusing on the effects of local geometric features on mass transfer from blood to artery walls. Using a previously developed characteristic/finite element scheme for solving advection-dominated transport problems, mass transfer calculations were performed in a rigid, anatomically realistic model of a human RCA. A qualitative and quantitative examination of the RCA geometry was also carried out. The concentration field within the RCA was seen to closely follow primary and secondary flow features. Local variations in mass transfer patterns due to geometric features were significant and much larger in magnitude than local variations in wall shear stress. We conclude that the complex secondary flows in a realistic arterial model can produce very substantial local variations in blood-wall mass transfer rates, and may be important in atherogenesis. Further, RCA mass transfer patterns are more sensitive to local geometric features than are wall shear stress patterns. PMID:11284666

  3. Mass Measurement with Rare-RI Rin

    NASA Astrophysics Data System (ADS)

    Ozawa, Akira

    2014-09-01

    Mass measurement with Rare-RI Ring in RIKEN RI Beam Factory (RIBF) will be presented. The main purpose of Rare-RI Ring is to measure the mass for very neutron-rich nuclei, the production rate of which is very small (rare RI) and the life-time of which is predicted to be very short (less than 10 ms). In Rare-RI Ring, mass measurements will be performed based on isochronous mass spectrometry. There are two innovative apparatus in Rare-RI Ring: individual injection, which can realize the injection of 200 A MeV rare RI one-by-one, and a cyclotron-like storage ring, which allows high isochronous magnetic fields with large angular and momentum acceptances (~1%). By these apparatus, we will achieve a 10-6 mass resolution, and will be able to access rare RI, the production rate of which is down to 1 event/day/pnA in RIBF. Construction of Rare-RI Ring has started from the 2012 fiscal year. Construction of the storage ring itself was almost completed. In this fiscal year, we succeeded to store alphas from 241Am source and to check the production of isochronous fields in the storage ring. In this talk, present status of Rare-RI Ring and the possible mass measurement there will be presented.

  4. Mass transportation mechanism in electric-biased carbon nanotubes.

    PubMed

    Zhao, Jiong; Huang, Jia-Qi; Wei, Fei; Zhu, Jing

    2010-11-10

    The mass transportation mechanism in electric-biased carbon nanotubes (CNTs) is investigated experimentally. Except for the widely accepted electromigration mechanism, we find out the thermal effect can also induce the mass transportation in the form of thermomigration or thermal evaporation. Moreover, the convincing in situ transmission electron microscope experiment results show the thermal gradient force overrides the electromigration force in most conditions, according to specific parameters of the CNTs and "cargos". A full analysis on the thermal gradient force and electromigration force imposed on the cargos is given, thus our experimental results are well explained and understood.

  5. Penning trap mass measurement of 72Br

    NASA Astrophysics Data System (ADS)

    Valverde, A. A.; Bollen, G.; Cooper, K.; Eibach, M.; Gulyuz, K.; Izzo, C.; Morrissey, D. J.; Ringle, R.; Sandler, R.; Schwarz, S.; Sumithrarachchi, C. S.; Villari, A. C. C.

    2015-03-01

    The Low Energy Beam and Ion Trap (LEBIT) Penning trap mass spectrometer was used to perform an improved-precision mass measurement of 72Br and the low-lying isomeric state, Brm72, giving mass excesses of -59 062.2 (1.0 )keV and -58 960.9 (1.2 )keV , respectively. These values are consistent with the values from the 2012 atomic mass evaluation [Chin. Phys. C 36, 1603 (2012), 10.1088/1674-1137/36/12/003] and the Nubase2012 evaluation of nuclear properties [Chin. Phys. C 36, 1157 (2012), 10.1088/1674-1137/36/12/001]. The uncertainties on the mass of the ground state and isomeric state have been reduced by a factor of seven.

  6. A method to measure the axion mass

    NASA Astrophysics Data System (ADS)

    Carboni, G.

    1981-05-01

    We have calculated the decay rate of the triplet state of positronium into axion + gamma, under the hypothesis that the axion mass is less than 1 MeV. The branching ratio is found to be ~3 × 10-8. We describe a possible experiment that could detect the axion and measure its mass. On leave from Istituto Nazionale di Fisica Nuclear, Sezione di Pisa, Pisa, Italy.

  7. Measurement of the W boson mass.

    PubMed

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Ancu, L S; Andeen, T; Anzelc, M S; Aoki, M; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Atramentov, O; Avila, C; Backusmayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calfayan, P; Calpas, B; Calvet, S; Cammin, J; Carrasco-Lizarraga, M A; Carrera, E; Carvalho, W; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Cheu, E; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Cutts, D; Cwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; Devaughan, K; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duflot, L; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Escalier, M; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gómez, B; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinson, A P; Heintz, U; Hensel, C; Heredia-De La Cruz, I; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jamin, D; Jesik, R; Johns, K; Johnson, C; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Juste, A; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kozelov, A V; Kraus, J; Kuhl, T; Kumar, A; Kupco, A; Kurca, T; Kuzmin, V A; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, W M; Leflat, A; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Mättig, P; Magaña-Villalba, R; Mal, P K; Malik, S; Malyshev, V L; Maravin, Y; Martin, B; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Mendoza, L; Menezes, D; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Mondal, N K; Montgomery, H E; Moore, R W; Moulik, T; Muanza, G S; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Novaes, S F; Nunnemann, T; Obrant, G; Ochando, C; Onoprienko, D; Orduna, J; Oshima, N; Osman, N; Osta, J; Otec, R; Otero Y Garzón, G J; Owen, M; Padilla, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Pétroff, P; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Popov, A V; Prewitt, M; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Siccardi, V; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strandberg, J; Strang, M A; Strauss, E; Strauss, M; Ströhmer, R; Strom, D; Stutte, L; Sumowidagdo, S; Svoisky, P; Takahashi, M; Tanasijczuk, A; Taylor, W; Tiller, B; Titov, M; Tokmenin, V V; Torchiani, I; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; van den Berg, P J; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P; Vertogradov, L S; Verzocchi, M; Vesterinen, M; Vilanova, D; Vint, P; Vokac, P; Wagner, R; Wahl, H D; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, G; Weber, M; Welty-Rieger, L; Wenger, A; Wetstein, M; White, A; Wicke, D; Williams, M R J; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Xu, C; Yacoob, S; Yamada, R; Yang, W-C; Yasuda, T; Yatsunenko, Y A; Ye, Z; Yin, H; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zeitnitz, C; Zelitch, S; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zivkovic, L; Zutshi, V; Zverev, E G

    2009-10-01

    We present a measurement of the W boson mass in W-->e(nu) decays using 1 fb-1 of data collected with the D0 detector during Run II of the Fermilab Tevatron collider. With a sample of 499830 W-->e(nu) candidate events, we measure M(W)=80.401+/-0.043 GeV. This is the most precise measurement from a single experiment. PMID:19905560

  8. Mass and Lifetime Measurements in Storage Rings

    SciTech Connect

    Weick, H.; Beckert, K.; Beller, P.; Bosch, F.; Dimopoulou, C.; Kozhuharov, C.; Kurcewicz, J.; Mazzocco, M.; Nociforo, C.; Nolden, F.; Steck, M.; Sun, B.; Winkler, M.; Brandau, C.; Chen, L.; Geissel, H.; Knoebel, R.; Litvinov, S. A.; Litvinov, Yu. A.; Scheidenberger, C.

    2007-05-22

    Masses of nuclides covering a large area of the chart of nuclides can be measured in storage rings where many ions circulate at the same time. In this paper the recent progress in the analysis of Schottky mass spectrometry data is presented as well as the technical improvements leading to higher accuracy for isochronous mass measurements with a time-of-flight detector. The high sensitivity of the Schottky method down to single ions allows to measure lifetimes of nuclides by observing mother and daughter nucleus simultaneously. In this way we investigated the decay of bare and H-like 140Pr. As we could show the lifetime can be even shortened compared to those of atomic nuclei despite of a lower number of electrons available for internal conversion or electron capture.All these techniques will be implemented with further improvements at the storage rings of the new FAIR facility at GSI in the future.

  9. Geoelectrical Measurement of Multi-Scale Mass Transfer Parameters

    SciTech Connect

    Day-Lewis, Frederick David; Singha, Kamini; Johnson, Timothy C.; Haggerty, Roy; Binley, Andrew; Lane, John W.

    2014-11-25

    Mass transfer affects contaminant transport and is thought to control the efficiency of aquifer remediation at a number of sites within the Department of Energy (DOE) complex. An improved understanding of mass transfer is critical to meeting the enormous scientific and engineering challenges currently facing DOE. Informed design of site remedies and long-term stewardship of radionuclide-contaminated sites will require new cost-effective laboratory and field techniques to measure the parameters controlling mass transfer spatially and across a range of scales. In this project, we sought to capitalize on the geophysical signatures of mass transfer. Previous numerical modeling and pilot-scale field experiments suggested that mass transfer produces a geoelectrical signature—a hysteretic relation between sampled (mobile-domain) fluid conductivity and bulk (mobile + immobile) conductivity—over a range of scales relevant to aquifer remediation. In this work, we investigated the geoelectrical signature of mass transfer during tracer transport in a series of controlled experiments to determine the operation of controlling parameters, and also investigated the use of complex-resistivity (CR) as a means of quantifying mass transfer parameters in situ without tracer experiments. In an add-on component to our grant, we additionally considered nuclear magnetic resonance (NMR) to help parse mobile from immobile porosities. Including the NMR component, our revised study objectives were to: 1. Develop and demonstrate geophysical approaches to measure mass-transfer parameters spatially and over a range of scales, including the combination of electrical resistivity monitoring, tracer tests, complex resistivity, nuclear magnetic resonance, and materials characterization; and 2. Provide mass-transfer estimates for improved understanding of contaminant fate and transport at DOE sites, such as uranium transport at the Hanford 300 Area. To achieve our objectives, we implemented a 3

  10. Measurement of the Top Quark Mass

    SciTech Connect

    Blair, R.E.; Byrum, K.L.; Kovacs, E.; Kuhlmann, S.E.; LeCompte, T.; Nodulman, L.; Breccia, L.; Brunetti, R.; Deninno, M.; Fiori, I.; Mazzanti, P.; Behrends, S.; Bensinger, J.; Blocker, C.; Kirsch, L.; Lamoureux, J.I.; Bonushkin, Y.; Hauser, J.; Lindgren, M.; Amadon, A.; Berryhill, J.; Contreras, M.; Culbertson, R.; Frisch, H.; Grosso-Pilcher, C.; Hohlmann, M.; Cronin-Hennessy, D.; Dittmann, J.R.; Goshaw, A.T.; Khazins, D.; Kowald, W.; Oh, S.H.; Albrow, M.G.; Atac, M.; Beretvas, A.; Berge, J.P.; Biery, K.; Binkley, M.; Buckley-Geer, E.; Byon-Wagner, A.; Chlebana, F.; Cihangir, S.; Cooper, J.; DeJongh, F.; Demina, R.; Derwent, P.F.; Elias, J.E.; Erdmann, W.; Flaugher, B.; Foster, G.W.; Freeman, J.; Geer, S.; Hahn, S.R.; Harris, R.M.; Incandela, J.; Jensen, H.; Joshi, U.; Kennedy, R.D.; Kephart, R.; Lammel, S.; Lewis, J.D.; Limon, P.; Lukens, P.; Maeshima, K.; Marriner, J.P.; Miao, T.; Mukherjee, A.; Nelson, C.; Newman-Holmes, C.; Patrick, J.; Klimenko, S.; Konigsberg, J.; Korytov, A.; Nomerotski, A.; Barone, M.; Bertolucci, S.; Cordelli, M.; DellAgnello, S.; Giromini, P.; Happacher, F.; Miscetti, S.; Parri, A.; Clark, A.G.; Couyoumtzelis, C.; Kambara, H.; Baumann, T.; Franklin, M.; Gordon, A.; Hamilton, R.; Huth, J.; and others

    1998-03-01

    We present a measurement of the top quark mass using a sample of t{bar t} decays into an electron or a muon, a neutrino, and four jets. The data were collected in p{bar p} collisions at {radical}(s)=1.8 TeV with the Collider Detector at Fermilab and correspond to an integrated luminosity of 109 pb{sup {minus}1} . We measure the top quark mass to be 175.9{plus_minus}4.8(stat){plus_minus}4.9( syst) GeV /c{sup 2} . {copyright} {ital 1998} {ital The American Physical Society}

  11. Measurements of classical transport of fast ions

    SciTech Connect

    Zhao, L.; Heidbrink, W.W.; Boehmer, H.; McWilliams, R.; Leneman, D.; Vincena, S.

    2005-05-15

    To study the fast-ion transport in a well controlled background plasma, a 3-cm diameter rf ion gun launches a pulsed, {approx}300 eV ribbon shaped argon ion beam parallel to or at 15 deg. to the magnetic field in the Large Plasma Device (LAPD) [W. Gekelman, H. Pfister, Z. Lucky, J. Bamber, D. Leneman, and J. Maggs, Rev. Sci. Instrum. 62, 2875 (1991)] at UCLA. The parallel energy of the beam is measured by a two-grid energy analyzer at two axial locations (z=0.32 m and z=6.4 m) from the ion gun in LAPD. The calculated ion beam slowing-down time is consistent to within 10% with the prediction of classical Coulomb collision theory using the LAPD plasma parameters measured by a Langmuir probe. To measure cross-field transport, the beam is launched at 15 deg. to the magnetic field. The beam then is focused periodically by the magnetic field to avoid geometrical spreading. The radial beam profile measurements are performed at different axial locations where the ion beam is periodically focused. The measured cross-field transport is in agreement to within 15% with the analytical classical collision theory and the solution to the Fokker-Planck kinetic equation. Collisions with neutrals have a negligible effect on the beam transport measurement but do attenuate the beam current.

  12. Mass transport mechanism in porous fuel cell electrodes

    NASA Technical Reports Server (NTRS)

    Jonsson, I.; Lindholm, I.

    1969-01-01

    Results of experiments on hydrogen-oxygen fuel cells show that higher current densities are obtained with cell anodes having a 100 micron thin active layer of porous nickel containing silver electrocatalyst. Increase in current density is attributed to a convective mass transport mechanism.

  13. A measurement of the W boson mass

    NASA Astrophysics Data System (ADS)

    Cavanaugh, Richard John

    1999-11-01

    A measurement of the W boson mass is presented using data taken by the ALEPH detector during the 1997 running of the Large Electron-Positron Collider II (LEPII) at the European Center for Particle Physics (CERN) near Geneva, Switzerland. A high efficiency, high purity analysis which selects and reconstructs semi-leptonic W+W- final states (W +W- --> jjlν) is employed to define the sample. To improve the mass resolution of the detector, a constrained kinematic fit is developed to impose four- momentum conservation on each selected event. An unbinned maximum likelihood fit to the constrained two dimensional WW mass distribution is then constructed to extract the W pole mass. With 56.84 pb-1 of data taken by the ALEPH detector near a center of mass energy of s = 183 GeV, the W boson is measured to have a mass of MW=80.20+/-0.19( stat)+/-0.06 (syst)GeV consistent with predictions from the Standard Model.

  14. Spatiotemporal characteristics of erosion processes along a steep climatic gradient in the NW Himalaya: Insights from satellite-rainfall data, mass-transport measurements, and surface-exposure dating

    NASA Astrophysics Data System (ADS)

    Bookhagen, B.; Strecker, M. R.; Niedermann, S.; Scherler, D.

    2011-12-01

    The intensity of the Indian summer-monsoon circulation varies at decadal to millennial time scales and affects the terrestrial and marine sediment records. The impact of climatic forcing on erosional and sedimentary processes and their manifestation in the landscape varies, depending on magnitude and size of the climatic events, as well as on the tectonic and geomorphic preconditioning of the landscape. Significant mass-transport processes during the large Pakistan flood 2010 and previous abnormal years have emphasized the importance of extreme events on shaping landscapes. Here, we analyze gauge and satellite-derived rainfall data combined with new cosmogenic nuclide surface-exposure ages and basin-wide erosion rates to elucidate the impact of climatic forcing on Earth-surface processes at different time scales. The NW Himalaya is located at the western end of the monsoonal conveyer belt that transports moisture from the Bay of Bengal to the Sutlej Valley and farther west. Orographic rainfall processes at the southern Himalayan mountain front create a steep south-to-north rainfall gradient. The tail and northward end of the rainfall distribution decays rapidly with only little or no moisture reaching the southern Tibetan Plateau. However, during recent, abnormally strong monsoon years rainfall did reach the presently arid to semi-arid regions of the northern Himalaya and southern Tibetan Plateau. Gauge and satellite-derived rainfall data show that erosion in these environments does not follow the mean annual rainfall distribution. Instead, we document the northward penetration of rainfall into the orogen and highlight the importance of extreme-event rainfall (>90th percentile) on sediment-transport processes by analyzing basin-wide erosion rates tied into a specific stream-power model. Similarly, but on longer time scales (> 100 yr), rainfall propagated farther into the orogen during a generally stronger monsoon circulation in the early Holocene. During these

  15. Body Mass Index Measurement in Schools

    ERIC Educational Resources Information Center

    Nihiser, Allison J.; Lee, Sarah M.; Wechsler, Howell; McKenna, Mary; Odom, Erica; Reinold, Chris; Thompson, Diane; Grummer-Strawn, Larry

    2007-01-01

    Background: School-based body mass index (BMI) measurement has attracted much attention across the nation from researchers, school officials, legislators, and the media as a potential approach to address obesity among youth. Methods: An expert panel, convened by the Centers for Disease Control and Prevention (CDC) in 2005, reviewed and provided…

  16. Thermodynamically coupled mass transport processes in a saturated clay

    SciTech Connect

    Carnahan, C.L.

    1984-11-01

    Gradients of temperature, pressure, and fluid composition in saturated clays give rise to coupled transport processes (thermal and chemical osmosis, thermal diffusion, ultrafiltration) in addition to the direct processes (advection and diffusion). One-dimensional transport of water and a solute in a saturated clay subjected to mild gradients of temperature and pressure was simulated numerically. When full coupling was accounted for, volume flux (specific discharge) was controlled by thermal osmosis and chemical osmosis. The two coupled fluxes were oppositely directed, producing a point of stagnation within the clay column. Solute flows were dominated by diffusion, chemical osmosis, and thermal osmosis. Chemical osmosis produced a significant flux of solute directed against the gradient of solute concentration; this effect reduced solute concentrations relative to the case without coupling. Predictions of mass transport in clays at nuclear waste repositories could be significantly in error if coupled transport processes are not accounted for. 14 references, 8 figures, 1 table.

  17. A Global Assessment of Accelerations in Mass Transport of Surface Geophysical Fluid

    NASA Astrophysics Data System (ADS)

    Wu, X.; Heflin, M. B.

    2015-12-01

    Mass transport in the Earth's surface geophysical fluid layer has complex spatiotemporal patterns. The GRACE gravity mission provides an unprecedented global capability to monitor this important process with high accuracy and resolution. Accurate assessments of global mass transport patterns and budget also depend critically on changes in degree-1 coefficients (geocenter motion) and in Earth's dynamic oblateness coefficient J2. We combine GRACE measurements, time series of GNSS data, JPL's ECCO ocean bottom pressure model, and high-resolution loose a priori models of mass variation regimes to derive complete spherical harmonic spectra of detrended mass variations up to degree and order 180. Mass accelerations are estimated along with linear, annual, semiannual, and the 161-day tidal aliasing components from coefficient time series. The appropriateness of a priori information and estimate uncertainties are further evaluated by variance component estimation and residual statistics of fitting the time series. During the GRACE data period of 2002.2-2015.0, accelerations in mass transport are geographically uneven with significant positive or negative accelerations in various parts of the world. While Greenland and West Antarctica show strong accelerated mass losses, Alaska and the Arctic Ocean have significant positive accelerations with reversals of earlier mass loss trends. No evidence of non-Arctic global mean sea level acceleration due to mass has been found. Depending on region, some estimated accelerations are also not steady over time due to large irregular and interannual variations.

  18. Mass transport theory for the Toda lattices, dispersive and dissipative

    NASA Astrophysics Data System (ADS)

    Horii, Zene

    2005-05-01

    To establish mass transport theory on nonlinear lattices, we formulate the Korteweg-deVries (KdV) equation and the Burgers equation using the flow variable representation so as to facilitate comparison with the Boltzmann equation and with the Cahn-Hilliard equation in classical statistical mechanics. We also study Toda lattice microdynamics using the Flaschka representation, and compare with the Liouville equation. Like the linear diffusion equation, the Boltzmann equation and the Liouville equation are to be solved for a distribution function, which is intrinsically probabilistic. Transport theory in linear systems is governed by the isotropic motions of the kinetic equations. In contrast, the KdV perturbation equation derived from the Toda lattice microdynamics expresses hydrodynamic mass transport. The KdV equation in hydrodynamics and the Burgers equation in thermodynamics do not involve a probability distribution function. The nonlinear lattices do not retain isotropy of the mass transport equations. In consequence, it is proposed that in the presence of hydrodynamic flows to the left, KdV wave propagation proceeds to the right. This basic property of the KdV system is extended to thermodynamics in the Burgers system. These features arise because linear systems are driven towards an equilibrium by molecular collisions, whereas the inhomogeneities of the nonlinear lattices are generated by the potential energy of interaction. Diffusion as expressed by the Burgers equation is governed not only by a chemical potential, but also by the Toda lattice potential energy.

  19. The role of mass transport in protein crystallization.

    PubMed

    García-Ruiz, Juan Manuel; Otálora, Fermín; García-Caballero, Alfonso

    2016-02-01

    Mass transport takes place within the mesoscopic to macroscopic scale range and plays a key role in crystal growth that may affect the result of the crystallization experiment. The influence of mass transport is different depending on the crystallization technique employed, essentially because each technique reaches supersaturation in its own unique way. In the case of batch experiments, there are some complex phenomena that take place at the interface between solutions upon mixing. These transport instabilities may drastically affect the reproducibility of crystallization experiments, and different outcomes may be obtained depending on whether or not the drop is homogenized. In diffusion experiments with aqueous solutions, evaporation leads to fascinating transport phenomena. When a drop starts to evaporate, there is an increase in concentration near the interface between the drop and the air until a nucleation event eventually takes place. Upon growth, the weight of the floating crystal overcomes the surface tension and the crystal falls to the bottom of the drop. The very growth of the crystal then triggers convective flow and inhomogeneities in supersaturation values in the drop owing to buoyancy of the lighter concentration-depleted solution surrounding the crystal. Finally, the counter-diffusion technique works if, and only if, diffusive mass transport is assured. The technique relies on the propagation of a supersaturation wave that moves across the elongated protein chamber and is the result of the coupling of reaction (crystallization) and diffusion. The goal of this review is to convince protein crystal growers that in spite of the small volume of the typical protein crystallization setup, transport plays a key role in the crystal quality, size and phase in both screening and optimization experiments.

  20. The role of mass transport in protein crystallization.

    PubMed

    García-Ruiz, Juan Manuel; Otálora, Fermín; García-Caballero, Alfonso

    2016-02-01

    Mass transport takes place within the mesoscopic to macroscopic scale range and plays a key role in crystal growth that may affect the result of the crystallization experiment. The influence of mass transport is different depending on the crystallization technique employed, essentially because each technique reaches supersaturation in its own unique way. In the case of batch experiments, there are some complex phenomena that take place at the interface between solutions upon mixing. These transport instabilities may drastically affect the reproducibility of crystallization experiments, and different outcomes may be obtained depending on whether or not the drop is homogenized. In diffusion experiments with aqueous solutions, evaporation leads to fascinating transport phenomena. When a drop starts to evaporate, there is an increase in concentration near the interface between the drop and the air until a nucleation event eventually takes place. Upon growth, the weight of the floating crystal overcomes the surface tension and the crystal falls to the bottom of the drop. The very growth of the crystal then triggers convective flow and inhomogeneities in supersaturation values in the drop owing to buoyancy of the lighter concentration-depleted solution surrounding the crystal. Finally, the counter-diffusion technique works if, and only if, diffusive mass transport is assured. The technique relies on the propagation of a supersaturation wave that moves across the elongated protein chamber and is the result of the coupling of reaction (crystallization) and diffusion. The goal of this review is to convince protein crystal growers that in spite of the small volume of the typical protein crystallization setup, transport plays a key role in the crystal quality, size and phase in both screening and optimization experiments. PMID:26841759

  1. The negative role of turbulence in estuarine mass transport

    NASA Astrophysics Data System (ADS)

    Nunes Vaz, Richard A.; Lennon, Geoffrey W.; de Silva Samarasinghe, Jayantha R.

    1989-04-01

    It is competition between the various stratifying and mixing influences which determines the character of stratification in an estuary. Borrowing concepts which have been successfully applied to the discussion of stratification in shelf seas, a quantitative basis for determining the potential energy associated with vertical structure in estuaries is derived. The formulation, along similar lines to that of Bowden (1981), provides a simple but comprehensive method of incorporating many relevant stratifying and mixing influences in a given problem, and is also shown to be capable of rearrangement into forms akin to the estuarine Richardson number which is commonly found in discussions of estuarine statification. The paper argues, based on a survey of the literature, that in wide, relatively well-mixed estuaries, the greatest longitudinal mass flux occurs at times when stratification is most developed, that is, when the turbulent kinetic energy in the water column is at a minimum. Modulation of turbulence, principally at various tidal frequencies, causes a pulsing of the mass flux in which the contribution of each pulse increases non-linearly as the period of the modulation increases. Some, possibly significant, changes to the state of stratification and to the corresponding mass transport may occur in association with slack water periods. However, the spring-neap cycle is proposed to have a far greater influence on stratification, mass transport and the long-term mass balance in estuaries, and recent observational studies lend support to this position.

  2. Optimum periodicity of repeated contractile actions applied in mass transport

    NASA Astrophysics Data System (ADS)

    Ahn, Sungsook; Lee, Sang Joon

    2015-01-01

    Dynamically repeated periodic patterns are abundant in natural and artificial systems, such as tides, heart beats, stock prices, and the like. The characteristic repeatability and periodicity are expected to be optimized in effective system-specific functions. In this study, such optimum periodicity is experimentally evaluated in terms of effective mass transport using one-valve and multi-valve systems working in contractile fluid flows. A set of nanoscale gating functions is utilized, operating in nanocomposite networks through which permeates selectively pass under characteristic contractile actions. Optimized contractile periodicity exists for effective energy impartment to flow in a one-valve system. In the sequential contractile actions for a multi-valve system, synchronization with the fluid flow is critical for effective mass transport. This study provides fundamental understanding on the various repeated periodic patterns and dynamic repeatability occurring in nature and mechanical systems, which are useful for broad applications.

  3. Optimum periodicity of repeated contractile actions applied in mass transport

    PubMed Central

    Ahn, Sungsook; Lee, Sang Joon

    2015-01-01

    Dynamically repeated periodic patterns are abundant in natural and artificial systems, such as tides, heart beats, stock prices, and the like. The characteristic repeatability and periodicity are expected to be optimized in effective system-specific functions. In this study, such optimum periodicity is experimentally evaluated in terms of effective mass transport using one-valve and multi-valve systems working in contractile fluid flows. A set of nanoscale gating functions is utilized, operating in nanocomposite networks through which permeates selectively pass under characteristic contractile actions. Optimized contractile periodicity exists for effective energy impartment to flow in a one-valve system. In the sequential contractile actions for a multi-valve system, synchronization with the fluid flow is critical for effective mass transport. This study provides fundamental understanding on the various repeated periodic patterns and dynamic repeatability occurring in nature and mechanical systems, which are useful for broad applications. PMID:25622949

  4. Measuring neutrino masses with weak lensing

    SciTech Connect

    Wong, Yvonne Y. Y.

    2006-11-17

    Weak gravitational lensing of distant galaxies by large scale structure (LSS) provides an unbiased way to map the matter distribution in the low redshift universe. This technique, based on the measurement of small distortions in the images of the source galaxies induced by the intervening LSS, is expected to become a key cosmological probe in the future. We discuss how future lensing surveys can probe the sum of the neutrino masses at the 0 05 eV level.

  5. Mass spectrometric measurements of atmospheric composition

    NASA Technical Reports Server (NTRS)

    Hoffman, J. H.

    1974-01-01

    The development of a magnetic sector field analyzer for continuous sampling and measurement of outer planetary atmospheres is discussed. Special features of the analyzer include a dynamic range of 10 to the minus 7th power, a mass range from 1 to 48 AMU, two ion sensitivities, a special scan time of 35 sec at 14 BPS, and the use of ion counting techniques for analysis.

  6. Mass transport in bedded salt and salt interbeds

    SciTech Connect

    Hwang, Y.; Pigford, T.H.; Chambre, P.L.; Lee, W.W.L.

    1989-08-01

    Salt is the proposed host rock for geologic repositories of nuclear waste in several nations because it is nearly dry and probably impermeable. Although experiments and experience at potential salt sites indicate that salt may contain brine, the low porosity, creep, and permeability of salt make it still a good choice for geologic isolation. In this paper we summarize several mass-transfer and transport analyses of salt repositories. The mathematical details are given in our technical reports.

  7. Miocene mass-transport sediments, Troodos Massif, Cyprus

    USGS Publications Warehouse

    Lord, A.R.; Harrison, R.W.; BouDagher-Fadel, M.; Stone, B.D.; Varol, O.

    2009-01-01

    Sediment mass-transport layers of submarine origin on the northern and southern flanks of the Troodos ophiolitic massif are dated biostratigraphically as early Miocene and late Miocene, respectively and therefore represent different seismogenic events in the uplift and erosional history of the Troodos terrane. Analysis of such events has potential for documenting Miocene seismic and uplift events regionally in the context of changing stress field directions and plate vectors through time. ?? 2009 The Geologists' Association.

  8. Measurement of the W boson mass

    SciTech Connect

    Kotwal, A.V.; D0 Collaboration

    1996-11-01

    We present a preliminary measurement of the {ital W} boson mass using data collected by the D{null} experiment at the Fermilab Tevatron during the 1994-1995 collider run 1b. We use {ital W} {r_arrow} {ital e}{nu} decays to extract the {ital W} mass from the observed spectrum of transverse mass of the electron ({vert_bar}{eta}{vert_bar} {lt} 1. 2) and the inferred neutrino We use {ital Z}{sup 0} {r_arrow} {ital ee} decays to constrain our model of the detector response. We measure {ital m}{sub W}/{ital m}{sub Z} = 0.8815 {+-} 0.0011({ital stat}) {+-} 0.0014({ital syst}) and {ital m}{sub W} = 80.38 {+-} 0.07 ({ital W stat}) {+-} 0.13({ital syst}) GeV. Combining this result with our previous measurement from the 1992-1993 data, we obtain {ital m}{sub W} = 80.37 {+-} 0.15 GeV (errors combined in quadrature).

  9. Membranes for nanometer-scale mass fast transport

    DOEpatents

    Bakajin, Olgica; Holt, Jason; Noy, Aleksandr; Park, Hyung Gyu

    2011-10-18

    Nanoporous membranes comprising single walled, double walled, and multiwalled carbon nanotubes embedded in a matrix material were fabricated for fluid mechanics and mass transfer studies on the nanometer scale and commercial applications. Average pore size can be 2 nm to 20 nm, or seven nm or less, or two nanometers or less. The membrane can be free of large voids spanning the membrane such that transport of material such as gas or liquid occurs exclusively through the tubes. Fast fluid, vapor, and liquid transport are observed. Versatile micromachining methods can be used for membrane fabrication. A single chip can comprise multiple membranes. These membranes are a robust platform for the study of confined molecular transport, with applications in liquid and gas separations and chemical sensing including desalination, dialysis, and fabric formation.

  10. Vortical ciliary flows actively enhance mass transport in reef corals.

    PubMed

    Shapiro, Orr H; Fernandez, Vicente I; Garren, Melissa; Guasto, Jeffrey S; Debaillon-Vesque, François P; Kramarsky-Winter, Esti; Vardi, Assaf; Stocker, Roman

    2014-09-16

    The exchange of nutrients and dissolved gasses between corals and their environment is a critical determinant of the growth of coral colonies and the productivity of coral reefs. To date, this exchange has been assumed to be limited by molecular diffusion through an unstirred boundary layer extending 1-2 mm from the coral surface, with corals relying solely on external flow to overcome this limitation. Here, we present direct microscopic evidence that, instead, corals can actively enhance mass transport through strong vortical flows driven by motile epidermal cilia covering their entire surface. Ciliary beating produces quasi-steady arrays of counterrotating vortices that vigorously stir a layer of water extending up to 2 mm from the coral surface. We show that, under low ambient flow velocities, these vortices, rather than molecular diffusion, control the exchange of nutrients and oxygen between the coral and its environment, enhancing mass transfer rates by up to 400%. This ability of corals to stir their boundary layer changes the way that we perceive the microenvironment of coral surfaces, revealing an active mechanism complementing the passive enhancement of transport by ambient flow. These findings extend our understanding of mass transport processes in reef corals and may shed new light on the evolutionary success of corals and coral reefs.

  11. Vortical ciliary flows actively enhance mass transport in reef corals

    PubMed Central

    Shapiro, Orr H.; Fernandez, Vicente I.; Garren, Melissa; Guasto, Jeffrey S.; Debaillon-Vesque, François P.; Kramarsky-Winter, Esti; Vardi, Assaf; Stocker, Roman

    2014-01-01

    The exchange of nutrients and dissolved gasses between corals and their environment is a critical determinant of the growth of coral colonies and the productivity of coral reefs. To date, this exchange has been assumed to be limited by molecular diffusion through an unstirred boundary layer extending 1–2 mm from the coral surface, with corals relying solely on external flow to overcome this limitation. Here, we present direct microscopic evidence that, instead, corals can actively enhance mass transport through strong vortical flows driven by motile epidermal cilia covering their entire surface. Ciliary beating produces quasi-steady arrays of counterrotating vortices that vigorously stir a layer of water extending up to 2 mm from the coral surface. We show that, under low ambient flow velocities, these vortices, rather than molecular diffusion, control the exchange of nutrients and oxygen between the coral and its environment, enhancing mass transfer rates by up to 400%. This ability of corals to stir their boundary layer changes the way that we perceive the microenvironment of coral surfaces, revealing an active mechanism complementing the passive enhancement of transport by ambient flow. These findings extend our understanding of mass transport processes in reef corals and may shed new light on the evolutionary success of corals and coral reefs. PMID:25192936

  12. RWPV bioreactor mass transport: earth-based and in microgravity

    NASA Technical Reports Server (NTRS)

    Begley, Cynthia M.; Kleis, Stanley J.

    2002-01-01

    Mass transport and mixing of perfused scalar quantities in the NASA Rotating Wall Perfused Vessel bioreactor are studied using numerical models of the flow field and scalar concentration field. Operating conditions typical of both microgravity and ground-based cell cultures are studied to determine the expected vessel performance for both flight and ground-based control experiments. Results are presented for the transport of oxygen with cell densities and consumption rates typical of colon cancer cells cultured in the RWPV. The transport and mixing characteristics are first investigated with a step change in the perfusion inlet concentration by computing the time histories of the time to exceed 10% inlet concentration. The effects of a uniform cell utilization rate are then investigated with time histories of the outlet concentration, volume average concentration, and volume fraction starved. It is found that the operating conditions used in microgravity produce results that are quite different then those for ground-based conditions. Mixing times for microgravity conditions are significantly shorter than those for ground-based operation. Increasing the differential rotation rates (microgravity) increases the mixing and transport, while increasing the mean rotation rate (ground-based) suppresses both. Increasing perfusion rates enhances mass transport for both microgravity and ground-based cases, however, for the present range of operating conditions, above 5-10 cc/min there are diminishing returns as much of the inlet fluid is transported directly to the perfusion exit. The results show that exit concentration is not a good indicator of the concentration distributions in the vessel. In microgravity conditions, the NASA RWPV bioreactor with the viscous pump has been shown to provide an environment that is well mixed. Even when operated near the theoretical minimum perfusion rates, only a small fraction of the volume provides less than the required oxygen levels

  13. RWPV bioreactor mass transport: earth-based and in microgravity.

    PubMed

    Begley, Cynthia M; Kleis, Stanley J

    2002-11-20

    Mass transport and mixing of perfused scalar quantities in the NASA Rotating Wall Perfused Vessel bioreactor are studied using numerical models of the flow field and scalar concentration field. Operating conditions typical of both microgravity and ground-based cell cultures are studied to determine the expected vessel performance for both flight and ground-based control experiments. Results are presented for the transport of oxygen with cell densities and consumption rates typical of colon cancer cells cultured in the RWPV. The transport and mixing characteristics are first investigated with a step change in the perfusion inlet concentration by computing the time histories of the time to exceed 10% inlet concentration. The effects of a uniform cell utilization rate are then investigated with time histories of the outlet concentration, volume average concentration, and volume fraction starved. It is found that the operating conditions used in microgravity produce results that are quite different then those for ground-based conditions. Mixing times for microgravity conditions are significantly shorter than those for ground-based operation. Increasing the differential rotation rates (microgravity) increases the mixing and transport, while increasing the mean rotation rate (ground-based) suppresses both. Increasing perfusion rates enhances mass transport for both microgravity and ground-based cases, however, for the present range of operating conditions, above 5-10 cc/min there are diminishing returns as much of the inlet fluid is transported directly to the perfusion exit. The results show that exit concentration is not a good indicator of the concentration distributions in the vessel. In microgravity conditions, the NASA RWPV bioreactor with the viscous pump has been shown to provide an environment that is well mixed. Even when operated near the theoretical minimum perfusion rates, only a small fraction of the volume provides less than the required oxygen levels.

  14. Transport phenomena of crystal growth—heat and mass transfer

    NASA Astrophysics Data System (ADS)

    Rudolph, Peter

    2010-07-01

    Selected fundamentals of transport processes and their importance for crystal growth are given. First, principal parameters and equations of heat and mass transfer, like thermal flux, radiation and diffusion are introduced. The heat- and mass- balanced melt-solid and solution-solid interface velocities are derived, respectively. The today's significance of global numeric simulation for analysis of thermo-mechanical stress and related dislocation dynamics within the growing crystal is shown. The relation between diffusion and kinetic regime is discussed. Then, thermal and solutal buoyancy-driven and Marangoni convections are introduced. Their important interplay with the diffusion boundary layer, component and particle incorporation as well as morphological interface stability is demonstrated. Non-steady crystallization phenomena (striations) caused by convective fluctuations are considered. Selected results of global 3D numeric modeling are shown. Finally, advanced methods to control heat and mass transfer by external forces, such as accelerated container rotation, ultrasonic vibration and magnetic fields are discussed.

  15. A global assessment of accelerations in surface mass transport

    NASA Astrophysics Data System (ADS)

    Wu, Xiaoping; Heflin, Michael B.

    2015-08-01

    Water mass transport in the Earth's dynamic surface layer of atmosphere, cryosphere, and hydrosphere driven by various global change processes has complex spatiotemporal patterns. Here we determine global patterns and regional mean values of accelerations in surface mass variations during the Gravity Recovery and Climate Experiment (GRACE) mission's data span from 2002.2 to 2015.0. GRACE gravity data are supplemented by surface deformation from 607 Global Navigation Satellite System stations, an ocean bottom pressure model, satellite laser ranging, and loose a priori knowledge on mass variation regimes incorporating high-resolution geographic boundaries. While Greenland and West Antarctica have strong negative accelerations, Alaska and the Arctic Ocean show significant positive accelerations. In addition, the accelerations are not constant in time with some regions showing considerable variability due to irregular interannual changes. No evidence of significant nonsteric mean sea level acceleration has been found, but the uncertainty is quite large.

  16. Ion Neutral Mass Spectrometer Measurements from Titan

    NASA Technical Reports Server (NTRS)

    Waite, J. H., Jr.; Niemann, H.; Yelle, R. V.; Kasprzak, W.; Cravens, T.; Luhmann, J.; McNutt, R.; Ip, W.-H.; Gell, D.; Muller-Wordag, I. C. F.

    2005-01-01

    Introduction: The Ion Neutral Mass Spectrometer (INMS) aboard the Cassini orbiter has obtained the first in situ composition measurements of the neutral densities of molecular nitrogen, methane, argon, and a host of stable carbon-nitrile compounds in its first flyby of Titan. The bulk composition and thermal structure of the moon s upper atmosphere do not appear to be changed since the Voyager flyby in 1979. However, the more sensitive techniques provided by modern in-situ mass spectrometry also give evidence for large-spatial-scale large-amplitude atmospheric waves in the upper atmosphere and for a plethora of stable carbon-nitrile compounds above 1174 km. Furthermore, they allow the first direct measurements of isotopes of nitrogen, carbon, and argon, which provide interesting clues about the evolution of the atmosphere. The atmosphere was first accreted as ammonia and ammonia ices from the Saturn sub-nebula. Subsequent photochemistry likely converted the atmosphere into molecular nitrogen. The early atmosphere was 1.5 to 5 times more substantial and was lost via escape over the intervening 4.5 billion years due to the reduced gravity associated with the relatively small mass of Titan. Carbon in the form of methane has continued to outgas over time from the interior with much of it being deposited in the form of complex hydrocarbons on the surface and some of it also being lost to space.

  17. Measurement of neutrino masses from relative velocities.

    PubMed

    Zhu, Hong-Ming; Pen, Ue-Li; Chen, Xuelei; Inman, Derek; Yu, Yu

    2014-09-26

    We present a new technique to measure neutrino masses using their flow field relative to dark matter. Present day streaming motions of neutrinos relative to dark matter and baryons are several hundred km/s, comparable with their thermal velocity dispersion. This results in a unique dipole anisotropic distortion of the matter-neutrino cross power spectrum, which is observable through the dipole distortion in the cross correlation of different galaxy populations. Such a dipole vanishes if not for this relative velocity and so it is a clean signature for neutrino mass. We estimate the size of this effect and find that current and future galaxy surveys may be sensitive to these signature distortions. PMID:25302878

  18. Geomorphological characteristics and variability of Holocene mass-transport complexes, St. Lawrence River Estuary, Canada

    NASA Astrophysics Data System (ADS)

    Pinet, Nicolas; Brake, Virginia; Campbell, Calvin; Duchesne, Mathieu J.

    2015-01-01

    Recently acquired multibeam bathymetry data are used to investigate seafloor instability features along a 310 km-long segment of the St. Lawrence River Estuary. The analysis of this dataset indicates that submarine slides occur over a much larger area than previously recognized and that Holocene sediments are reworked by mass-transport along significant portions of both the northwest and southeast margins of the Laurentian Channel. In the surveyed area, 96 individual mass-transport complexes (MTCs) were identified representing 13% of the seabed. MTCs vary in area from less than 1 km2 to more than 40 km2 and exhibit various geomorphological signatures. Qualitative observation reveals an apparent disparity between MTCs that remain coherent and those that disintegrate during downslope transport evolving into a blocky morphological signature. For all MTCs, morphological parameters have been measured (area, length, and height) or calculated (slope and roughness). This quantitative analysis provides a unique opportunity to study these parameters in a statistically significant and homogeneous dataset located in a relatively small area that experienced a similar Quaternary history. In many cases, mass transport events appear to initiate in the vicinity of steep bedrock walls located along some segments of the estuary. The timing of mass-transport events was not constrained during this study. However, the fact that the region hosts the Charlevoix seismic zone, the most tectonically active area in eastern Canada, strongly suggests that earthquakes acted as a trigger for submarine landsliding.

  19. Precision mass measurements of highly charged ions

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, A. A.; Bale, J. C.; Brunner, T.; Chaudhuri, A.; Chowdhury, U.; Ettenauer, S.; Frekers, D.; Gallant, A. T.; Grossheim, A.; Lennarz, A.; Mane, E.; MacDonald, T. D.; Schultz, B. E.; Simon, M. C.; Simon, V. V.; Dilling, J.

    2012-10-01

    The reputation of Penning trap mass spectrometry for accuracy and precision was established with singly charged ions (SCI); however, the achievable precision and resolving power can be extended by using highly charged ions (HCI). The TITAN facility has demonstrated these enhancements for long-lived (T1/2>=50 ms) isobars and low-lying isomers, including ^71Ge^21+, ^74Rb^8+, ^78Rb^8+, and ^98Rb^15+. The Q-value of ^71Ge enters into the neutrino cross section, and the use of HCI reduced the resolving power required to distinguish the isobars from 3 x 10^5 to 20. The precision achieved in the measurement of ^74Rb^8+, a superallowed β-emitter and candidate to test the CVC hypothesis, rivaled earlier measurements with SCI in a fraction of the time. The 111.19(22) keV isomeric state in ^78Rb was resolved from the ground state. Mass measurements of neutron-rich Rb and Sr isotopes near A = 100 aid in determining the r-process pathway. Advanced ion manipulation techniques and recent results will be presented.

  20. Fission Yield Measurements by Inductively Coupled Plasma Mass-Spectrometry

    SciTech Connect

    Irina Glagolenko; Bruce Hilton; Jeffrey Giglio; Daniel Cummings; Karl Grimm; Richard McKnight

    2009-11-01

    Correct prediction of the fission products inventory in irradiated nuclear fuels is essential for accurate estimation of fuel burnup, establishing proper requirements for spent fuel transportation and storage, materials accountability and nuclear forensics. Such prediction is impossible without accurate knowledge of neutron induced fission yields. Unfortunately, the accuracy of the fission yields reported in the ENDF/B-VII.0 library is not uniform across all of the data and much of the improvement is desired for certain isotopes and fission products. We discuss our measurements of cumulative fission yields in nuclear fuels irradiated in thermal and fast reactor spectra using Inductively Coupled Plasma Mass Spectrometry.

  1. Updated Delft Mass Transport model DMT-2: computation and validation

    NASA Astrophysics Data System (ADS)

    Hashemi Farahani, Hassan; Ditmar, Pavel; Inacio, Pedro; Klees, Roland; Guo, Jing; Guo, Xiang; Liu, Xianglin; Zhao, Qile; Didova, Olga; Ran, Jiangjun; Sun, Yu; Tangdamrongsub, Natthachet; Gunter, Brian; Riva, Ricardo; Steele-Dunne, Susan

    2014-05-01

    A number of research centers compute models of mass transport in the Earth's system using primarily K-Band Ranging (KBR) data from the Gravity Recovery And Climate Experiment (GRACE) satellite mission. These models typically consist of a time series of monthly solutions, each of which is defined in terms of a set of spherical harmonic coefficients up to degree 60-120. One of such models, the Delft Mass Transport, release 2 (DMT-2), is computed at the Delft University of Technology (The Netherlands) in collaboration with Wuhan University. An updated variant of this model has been produced recently. A unique feature of the computational scheme designed to compute DMT-2 is the preparation of an accurate stochastic description of data noise in the frequency domain using an Auto-Regressive Moving-Average (ARMA) model, which is derived for each particular month. The benefits of such an approach are a proper frequency-dependent data weighting in the data inversion and an accurate variance-covariance matrix of noise in the estimated spherical harmonic coefficients. Furthermore, the data prior to the inversion are subject to an advanced high-pass filtering, which makes use of a spatially-dependent weighting scheme, so that noise is primarily estimated on the basis of data collected over areas with minor mass transport signals (e.g., oceans). On the one hand, this procedure efficiently suppresses noise, which are caused by inaccuracies in satellite orbits and, on the other hand, preserves mass transport signals in the data. Finally, the unconstrained monthly solutions are filtered using a Wiener filter, which is based on estimates of the signal and noise variance-covariance matrices. In combination with a proper data weighting, this noticeably improves the spatial resolution of the monthly gravity models and the associated mass transport models.. For instance, the computed solutions allow long-term negative trends to be clearly seen in sufficiently small regions notorious

  2. Mass and momentum turbulent transport experiments with confined swirling coaxial jets

    NASA Technical Reports Server (NTRS)

    Roback, R.; Johnson, B. V.

    1983-01-01

    Swirling coaxial jets mixing downstream, discharging into an expanded duct was conducted to obtain data for the evaluation and improvement of turbulent transport models currently used in a variety of computational procedures throughout the combustion community. A combination of laser velocimeter (LV) and laser induced fluorescence (LIF) techniques was employed to obtain mean and fluctuating velocity and concentration distributions which were used to derive mass and momentum turbulent transport parameters currently incorporated into various combustor flow models. Flow visualization techniques were also employed to determine qualitatively the time dependent characteristics of the flow and the scale of turbulence. The results of these measurements indicated that the largest momentum turbulent transport was in the r-z plane. Peak momentum turbulent transport rates were approximately the same as those for the nonswirling flow condition. The mass turbulent transport process for swirling flow was complicated. Mixing occurred in several steps of axial and radial mass transport and was coupled with a large radial mean convective flux. Mixing for swirling flow was completed in one-third the length required for nonswirling flow.

  3. Laboratory experiments of fine-scale mixing and mass transport within a coral canopy

    NASA Astrophysics Data System (ADS)

    Reidenbach, Matthew A.; Koseff, Jeffrey R.; Monismith, Stephen G.

    2007-07-01

    Laboratory experiments obtained fine scale measurements of turbulent shear stresses and rates of mixing and mass transfer over a nonliving bed of the coral, Porites compressa, the dominant species found in Kaneohe Bay, Hawaii. A reef canopy was placed in a recirculating wave-current flume and flow was generated that simulated the flow characteristics of the reef flat of Kaneohe Bay. Turbulence and velocity structure under both unidirectional and wave-dominated currents were measured using a two-dimensional laser Doppler anemometer. Mass transport measurements were made using a planar laser-induced fluorescence technique in which the scalar transport of Rhodamine 6G dye, fluxed from the surfaces of the coral, was quantified. Results show that the action of surface waves, interacting with the structure of the reef, can increase instantaneous shear and mixing up to six times compared to that of unidirectional currents. Maximum shear and mass transport events coincided with flow separation within the wave-current boundary layer and the ejection of vortices into the flow. Wave action also acted to increase the vertical flux of water from within the coral structure. The combined effects of increased turbulent stress and fluid exchange from the interior of the canopy increased mass flux due to wave action 2.3±0.5 times that measured for comparable unidirectional currents.

  4. Mass-height profile and total mass transport of wind eroded aeolian sediments from rangelands of the Indian Thar Desert

    NASA Astrophysics Data System (ADS)

    Mertia, R. S.; Santra, Priyabrata; Kandpal, B. K.; Prasad, R.

    2010-11-01

    Wind erosion is an active land degradation process in the Indian Thar Desert and severe dust storm events during hot summer months in the region are very common. Assessment of soil loss due to dust storm events from major land use systems of the Indian Thar Desert is highly essential for proper environmental planning. Characterization of the mass-height profile of wind eroded aeolian sediment is an important step to compute soil loss/mass transport but was not previously studied in the region. In the present study, aeolian mass fluxes (kg m -2) at different heights from soil surface were measured at two major rangelands in the Indian Thar Desert: Overgrazing rangeland at Jaisalmer (26°55'N and 70°57'E), and controlled grazing rangeland at Chandan (27°01'N and 71°01'E). Evaluation of several mass-height profile models revealed that a power decay function [ q( z) = az-b, where q( z) is the measured mass flux at an height of z (m) from soil surface; a and b are parameters of the equation] was best to characterize the mass-height relationship of aeolian sediments from the Indian Thar Desert. The average mass transport rate (kg m -1 day -1) or the total soil loss during hot summer months was significantly higher at the overgrazed rangeland site than at the controlled grazing rangeland site. Therefore, protection of existing rangelands, which comprise about 80% geographical area of the Indian Thar Desert may check the land degradation process due to wind erosion.

  5. PRECISION ELECTROWEAK MEASUREMENTS AND THE HIGGS MASS.

    SciTech Connect

    MARCIANO, W.J.

    2004-08-02

    The utility of precision electroweak measurements for predicting the Standard Model Higgs mass via quantum loop effects is discussed. Current constraints from m{sub w} and sin{sup 2} {theta}{sub w} (m{sub z}){sub {ovr MS}} imply a relatively light Higgs {approx}< 154 GeV which is consistent with Supersymmetry expectations. The existence of Supersymmetry is further suggested by a discrepancy between experiment and theory for the muon anomalous magnetic moment. Constraints from precision studies on other types of ''New Physics'' are also briefly described.

  6. Geoelectrical Measurement of Multi-Scale Mass Transfer Parameters

    SciTech Connect

    Day-Lewis, Frederick; Singha, Kamini; Haggerty, Roy; Johnson, Tim; Binley, Andrew; Lane, John

    2014-01-16

    Mass transfer affects contaminant transport and is thought to control the efficiency of aquifer remediation at a number of sites within the Department of Energy (DOE) complex. An improved understanding of mass transfer is critical to meeting the enormous scientific and engineering challenges currently facing DOE. Informed design of site remedies and long-term stewardship of radionuclide-contaminated sites will require new cost-effective laboratory and field techniques to measure the parameters controlling mass transfer spatially and across a range of scales. In this project, we sought to capitalize on the geophysical signatures of mass transfer. Previous numerical modeling and pilot-scale field experiments suggested that mass transfer produces a geoelectrical signature—a hysteretic relation between sampled (mobile-domain) fluid conductivity and bulk (mobile + immobile) conductivity—over a range of scales relevant to aquifer remediation. In this work, we investigated the geoelectrical signature of mass transfer during tracer transport in a series of controlled experiments to determine the operation of controlling parameters, and also investigated the use of complex-resistivity (CR) as a means of quantifying mass transfer parameters in situ without tracer experiments. In an add-on component to our grant, we additionally considered nuclear magnetic resonance (NMR) to help parse mobile from immobile porosities. Including the NMR component, our revised study objectives were to: 1. Develop and demonstrate geophysical approaches to measure mass-transfer parameters spatially and over a range of scales, including the combination of electrical resistivity monitoring, tracer tests, complex resistivity, nuclear magnetic resonance, and materials characterization; and 2. Provide mass-transfer estimates for improved understanding of contaminant fate and transport at DOE sites, such as uranium transport at the Hanford 300 Area. To achieve our objectives, we implemented a 3

  7. Street canyon aerosol pollutant transport measurements.

    PubMed

    Longley, I D; Gallagher, M W; Dorsey, J R; Flynn, M; Bower, K N; Allan, J D

    2004-12-01

    Current understanding of dispersion in street canyons is largely derived from relatively simple dispersion models. Such models are increasingly used in planning and regulation capacities but are based upon a limited understanding of the transport of substances within a real canyon. In recent years, some efforts have been made to numerically model localised flow in idealised canyons (e.g., J. Appl. Meteorol. 38 (1999) 1576-89) and stepped canyons (Assimakopoulos V. Numerical modelling of dispersion of atmospheric pollution in and above urban canopies. PhD thesis, Imperial College, London, 2001) but field studies in real canyons are rare. To further such an understanding, a measurement campaign has been conducted in an asymmetric street canyon with busy one-way traffic in central Manchester in northern England. The eddy correlation method was used to determine fluxes of size-segregated accumulation mode aerosol. Measurements of aerosol at a static location were made concurrently with measurements on a platform lift giving vertical profiles. Size-segregated measurements of ultrafine and coarse particle concentrations were also made simultaneously at various heights. In addition, a small mobile system was used to make measurements of turbulence at various pavement locations within the canyon. From this data, various features of turbulent transport and dispersion in the canyon will be presented. The concentration and the ventilation fluxes of vehicle-related aerosol pollutants from the canyon will be related to controlling factors. The results will also be compared with citywide ventilation data from a separate measurement campaign conducted above the urban canopy.

  8. Metal intercalation-induced selective adatom mass transport on graphene

    DOE PAGES

    Liu, Xiaojie; Wang, Cai -Zhuang; Hupalo, Myron; Lin, Hai -Qing; Ho, Kai -Ming; Thiel, Patricia A.; Tringides, Michael C.

    2016-03-29

    Recent experiments indicate that metal intercalation is a very effective method to manipulate the graphene-adatom interaction and control metal nanostructure formation on graphene. A key question is mass transport, i.e., how atoms deposited uniformly on graphene populate different areas depending on the local intercalation. Using first-principles calculations, we show that partially intercalated graphene, with a mixture of intercalated and pristine areas, can induce an alternating electric field because of the spatial variations in electron doping, and thus, an oscillatory electrostatic potential. As a result, this alternating field can change normal stochastic adatom diffusion to biased diffusion, leading to selective massmore » transport and consequent nucleation, on either the intercalated or pristine areas, depending on the charge state of the adatoms.« less

  9. Engineering Synergy: Energy and Mass Transport in Hybrid Nanomaterials.

    PubMed

    Cho, Eun Seon; Coates, Nelson E; Forster, Jason D; Ruminski, Anne M; Russ, Boris; Sahu, Ayaskanta; Su, Norman C; Yang, Fan; Urban, Jeffrey J

    2015-10-14

    An emerging class of materials that are hybrid in nature is propelling a technological revolution in energy, touching many fundamental aspects of energy-generation, storage, and conservation. Hybrid materials combine classical inorganic and organic components to yield materials that manifest new functionalities unattainable in traditional composites or other related multicomponent materials, which have additive function only. This Research News article highlights the exciting materials design innovations that hybrid materials enable, with an eye toward energy-relevant applications involving charge, heat, and mass transport. PMID:25754355

  10. Gasificaton Transport: A Multiphase CFD Approach & Measurements

    SciTech Connect

    Dimitri Gidaspow; Veeraya Jiradilok; Mayank Kashyap; Benjapon Chalermsinsuwan

    2009-02-14

    The objective of this project was to develop predictive theories for the dispersion and mass transfer coefficients and to measure them in the turbulent fluidization regime, using existing facilities. A second objective was to use our multiphase CFD tools to suggest optimized gasifier designs consistent with aims of Future Gen. We have shown that the kinetic theory based CFD codes correctly compute: (1) Dispersion coefficients; and (2) Mass transfer coefficients. Hence, the kinetic theory based CFD codes can be used for fluidized bed reactor design without any such inputs. We have also suggested a new energy efficient method of gasifying coal and producing electricity using a molten carbonate fuel cell. The principal product of this new scheme is carbon dioxide which can be converted into useful products such as marble, as is done very slowly in nature. We believe this scheme is a lot better than the canceled FutureGen, since the carbon dioxide is safely sequestered.

  11. Bilayer mass transport model for determining swelling and diffusion in coated, ultrathin membranes.

    PubMed

    Nadermann, Nichole K; Chan, Edwin P; Stafford, Christopher M

    2015-02-18

    Water transport and swelling properties of an ultrathin, selective polyamide layer with a hydrophilic polymer coating, i.e., a polymer bilayer, are studied using quartz crystal microbalance with dissipation (QCM-D). Specifically, QCM-D is used to measure the dynamic and equilibrium change in mass in a series of differential sorption experiments to determine the dependence of the apparent diffusion coefficient and equilibrium swelling of the bilayer as a function of the water vapor activity. To determine transport properties specific to the polyamide layer, sorption kinetics of the bilayer was modeled with a bilayer mass transport model. The swelling and water diffusion coefficients are interpreted according to the Painter-Shenoy polymer network swelling model and the solution-diffusion model, respectively.

  12. Model simulation and experiments of flow and mass transport through a nano-material gas filter

    SciTech Connect

    Yang, Xiaofan; Zheng, Zhongquan C.; Winecki, Slawomir; Eckels, Steve

    2013-11-01

    A computational model for evaluating the performance of nano-material packed-bed filters was developed. The porous effects of the momentum and mass transport within the filter bed were simulated. For the momentum transport, an extended Ergun-type model was employed and the energy loss (pressure drop) along the packed-bed was simulated and compared with measurement. For the mass transport, a bulk dsorption model was developed to study the adsorption process (breakthrough behavior). Various types of porous materials and gas flows were tested in the filter system where the mathematical models used in the porous substrate were implemented and validated by comparing with experimental data and analytical solutions under similar conditions. Good agreements were obtained between experiments and model predictions.

  13. Transported acid aerosols measured in southern Ontario

    NASA Astrophysics Data System (ADS)

    Keeler, Gerald J.; Spengler, John D.; Koutrakis, Petros; Allen, George A.; Raizenne, Mark; Stern, Bonnie

    During the period 29 June 1986-9 August 1986, a field health study assessing the acute health effects of air pollutants on children was conducted at a summer girls' camp on the northern shore of Lake Erie in SW Ontario. Continuous air pollution measurements of SO 2, O 3, NO x, particulate sulfates, light scattering, and meteorological measurements including temperature, dew point, and wind speed and direction were made. Twelve-hour integrated samples of size fractioned particles were also obtained using dichotomous samplers and Harvard impactors equipped with an ammonia denuder for subsequent hydrogen ion determination. Particulate samples were analyzed for trace elements by X-ray fluorescence and Neutron Activation, and for organic and elemental carbon by a thermal/optical technique. The measured aerosol was periodically very acidic with observed 12-h averaged H + concentrations in the range < 10-560 nmoles m -3. The aerosol H + appeared to represent the net strong acidity after H 2SO 4 reaction with NH 3(g). Average daytime concentrations were higher than night-time for aerosol H +, sulfate, fine mass and ozone. Prolonged episodes of atmospheric acidity, sulfate, and ozone were associated with air masses arriving at the measurement site from the west and from the southwest over Lake Erie. Sulfate concentrations measured at the lakeshore camp were more than twice those measured at inland sites during extreme pollution episodes. The concentration gradient observed with onshore flow was potentially due to enhanced deposition near the lakeshore caused by discontinuities in the meteorological fields in this region.

  14. Survey and Experimental Testing of Nongravimetric Mass Measurement Devices

    NASA Technical Reports Server (NTRS)

    Oakey, W. E.; Lorenz, R.

    1977-01-01

    Documentation presented describes the design, testing, and evaluation of an accelerated gravimetric balance, a low mass air bearing oscillator of the spring-mass type, and a centrifugal device for liquid mass measurement. A direct mass readout method was developed to replace the oscillation period readout method which required manual calculations to determine mass. A protoype 25 gram capacity micro mass measurement device was developed and tested.

  15. Experimental Studies on Mass Transport of Cadmium-Zinc Telluride by Physical Vapor Transport

    NASA Technical Reports Server (NTRS)

    Palosz, W.; Szofran, F. R.; Lehoczky, S. L.

    1995-01-01

    Experimental studies on mass transport of ternary compound, Cd(1-x)Zn(x)Te by physical vapor transport (PVT) for source compositions up to X = 0.21 are presented. The effect of thermochemical (temperatures, vapor composition) and other factors (preparation of the source, crystal growth rate, temperature gradient) on composition and composition profiles of the grown crystals were investigated. A steep decrease in the mass flux with an increase in X(crystal) for X less than 0.1, and a difference in composition between the source and the deposited material have been observed. The composition profiles of the crystals were found to depend on the density and pretreatment of the source, and on the temperature gradient in the source zone. The homogeneity of the crystals improves at low undercoolings and/or when an appropriate excess of metal constituents is present in the vapor phase. The experimental results are in good agreement with our thermochemical model of this system.

  16. Measurement of the top quark mass

    SciTech Connect

    Varnes, E.W.

    1997-12-31

    This dissertation describes the measurement of the top quark mass m{sub t} using events recorded during a 125 pb{sup -1} exposure of the D0 detector to {radical}s=1.8 TeV {anti p}p collisions. Six events consistent with the hypothesis t{anti t} {yields} bW{sup +}, {anti b}W{sup -} {yields} b{anti l}{nu}, {anti b}l{anti {nu}} form the dilepton sample. The kinematics of such events may be reconstructed for any assumed mt, and the likelihood of each such solution evaluated. A measurement of m{sub t} based on these relative solution likelihoods gives m{sub t} = 169.9 {+-} 14.8 (stat.) {+-} 3. 8 (syst.) GeV/c{sup 2}. A 2C kinematic fit is performed on a sample of 77 events consistent with t{anti t} {yields} bW{sup +}, {anti b}W{sup -} {yields} b{anti l}{nu}, {anti b}q{anti q} , and this, in combination with an estimate on the likelihood that each event is top, yields m{sub t} = 173.3 {+-} 5.6 (stat.) {+-} 6.2 (syst.) GeV/c{sup 2} . A combination of these two measurements gives m{sub t} = 173.1 {+-} 5.2 (stat.) {+-} 5.7 (syst.) GeV/c{sup 2}.

  17. Validation of bed-load transport measurements with time-sequenced bathymetric data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Advances in bathymetric data acquisition have made it possible to adopt a new, expedient method for measuring bed load transport in rivers. The method consists of comparing time sequenced bathymetric data sets and utilizing a simple mass conservation relation for bed load transport. Assuming a tri...

  18. NANONIS TRAMEA - A Quantum Transport Measurement System

    NASA Astrophysics Data System (ADS)

    Kampen, Thorsten; Thissen, Andreas; Schaff, Oliver; Pioda, Alessandro

    Nanonis Tramea is a quantum leap with respect to increased speed for transport measurements taking research onto a new level. Measurements which took several hours in the past can now be done in minutes without compromising signal quality. Tramea uses its fast, high-resolution, high-precision and ultra-low-noise outputs and inputs to generate and acquire up to 20000 data points per second on 24 channels in parallel. This is not only up to 1000 x faster than typical measurement systems but it is also time deterministic with highest precision. Here, the time separation between points is constant so that artefacts caused by unequal point spacings in non-deterministic measurement systems are avoided. The emphasis here is the real-time relation. Tramea comes with a built-in interface which allows for control of the instruments' basic functions from any programming environment. For users requiring more functionality and higher speeds a full-featured LabVIEW-based programming interface or scripting module are available as add-on modules. Due to the modularity and flexibility of the hardware and software architecture of Tramea upgrades with standardized add-on modules are possible. Non-standard requests can still be handled by the various programming options.

  19. 40 CFR 51.213 - Transportation control measures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false Transportation control measures. 51.213... Transportation control measures. (a) The plan must contain procedures for obtaining and maintaining data on actual emissions reductions achieved as a result of implementing transportation control measures. (b)...

  20. 40 CFR 51.213 - Transportation control measures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 2 2012-07-01 2012-07-01 false Transportation control measures. 51.213... Transportation control measures. (a) The plan must contain procedures for obtaining and maintaining data on actual emissions reductions achieved as a result of implementing transportation control measures. (b)...

  1. 40 CFR 51.213 - Transportation control measures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Transportation control measures. 51.213... Transportation control measures. (a) The plan must contain procedures for obtaining and maintaining data on actual emissions reductions achieved as a result of implementing transportation control measures. (b)...

  2. 40 CFR 51.213 - Transportation control measures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 2 2014-07-01 2014-07-01 false Transportation control measures. 51.213... Transportation control measures. (a) The plan must contain procedures for obtaining and maintaining data on actual emissions reductions achieved as a result of implementing transportation control measures. (b)...

  3. Calculating Measurement Uncertainties for Mass Spectrometry Data

    NASA Astrophysics Data System (ADS)

    Essex, R. M.; Goldberg, S. A.

    2006-12-01

    A complete and transparent characterization of measurement uncertainty is fundamentally important to the interpretation of analytical results. We have observed that the calculation and reporting of uncertainty estimates for isotopic measurement from a variety of analytical facilities are inconsistent, making it difficult to compare and evaluate data. Therefore, we recommend an approach to uncertainty estimation that has been adopted by both US national metrology facilities and is becoming widely accepted within the analytical community. This approach is outlined in the ISO "Guide to the Expression of Uncertainty in Measurement" (GUM). The GUM approach to uncertainty estimation includes four major steps: 1) Specify the measurand; 2) Identify uncertainty sources; 3) Quantify components by determining the standard uncertainty (u) for each component; and 4) Calculate combined standard uncertainty (u_c) by using established propagation laws to combine the various components. To obtain a desired confidence level, the combined standard uncertainty is multiplied by a coverage factor (k) to yield an expanded uncertainty (U). To be consistent with the GUM principles, it is also necessary create an uncertainty budget, which is a listing of all the components comprising the uncertainty and their relative contribution to the combined standard uncertainty. In mass spectrometry, Step 1 is normally the determination of an isotopic ratio for a particular element. Step 2 requires the identification of the many potential sources of measurement variability and bias including: gain, baseline, cup efficiency, Schottky noise, counting statistics, CRM uncertainties, yield calibrations, linearity calibrations, run conditions, and filament geometry. Then an equation expressing the relationship of all of the components to the measurement value must be written. To complete Step 3, these potential sources of uncertainty must be characterized (Type A or Type B) and quantified. This information

  4. Coupled effect of flow variability and mass transfer on contaminant transport and attenuation in groundwater

    NASA Astrophysics Data System (ADS)

    Cvetkovic, Vladimir; Fiori, Aldo; Dagan, Gedeon

    2016-04-01

    The driving mechanism of contaminant transport in aquifers is groundwater flow, which is controlled by boundary conditions and heterogeneity of hydraulic properties. In this work we show how hydrodynamics and mass transfer can be combined in a general analytical manner to derive a physically-based (or process-based) residence time distribution for a given integral scale of the hydraulic conductivity; the result can be applied for a broad class of linear mass transfer processes. The derived tracer residence time distribution is a transfer function with parameters to be inferred from combined field and laboratory measurements. It is scalable relative to the correlation length and applicable for an arbitrary statistical distribution of the hydraulic conductivity. Based on the derived residence time distribution, the coefficient of variation and skewness of contaminant residence time are illustrated assuming a log-normal hydraulic conductivity distribution and first-order mass transfer. We show that for a low Damkohler number the coefficient of variation is more strongly influenced by mass transfer than by heterogeneity, whereas skewness is more strongly influenced by heterogeneity. The derived physically-based residence time distribution for solute transport in heterogeneous aquifers is particularly useful for studying natural attenuation of contaminants. We illustrate the relative impacts of high heterogeneity and a generalised (non-Fickian) multi-rate mass transfer on natural attenuation defined as contaminant mass loss from injection to a downstream compliance boundary.

  5. Chemistry and mass transport of iodine in containment

    SciTech Connect

    Beahm, E.C.; Weber, C.F.; Kress, T.S.; Shockley, W.E.; Daish, S.R.

    1988-01-01

    TRENDS is a computer code for modeling behavior of iodine in containment. It tracks both chemical and physical changes and features such as calculation of radiation dose rates in water pools , radiolysis effects, hydrolysis, and deposition/revaporization on aerosols and structural surfaces. Every attempt has been made to account for all significant processes. Reaction rate constants for iodine hydrolysis and radiolysis were obtained by a variable algorithm that gives values closely modeling experimental data. TRENDS output provides the distribution of iodine in containment and release from containment as a function of time during a severe accident sequence. Initial calculations with TRENDS have shown that the amount of volatile iodine released from containment is sensitive to the value of the liquid-gas (evaporation) mass transport coefficient for I/sub 2/. 7 refs., 4 figs., 3 tabs.

  6. Density Functional Theory Calculations of Mass Transport in UO2

    SciTech Connect

    Andersson, Anders D.; Dorado, Boris; Uberuaga, Blas P.; Stanek, Christopher R.

    2012-06-26

    In this talk we present results of density functional theory (DFT) calculations of U, O and fission gas diffusion in UO{sub 2}. These processes all impact nuclear fuel performance. For example, the formation and retention of fission gas bubbles induce fuel swelling, which leads to mechanical interaction with the clad thereby increasing the probability for clad breach. Alternatively, fission gas can be released from the fuel to the plenum, which increases the pressure on the clad walls and decreases the gap thermal conductivity. The evolution of fuel microstructure features is strongly coupled to diffusion of U vacancies. Since both U and fission gas transport rates vary strongly with the O stoichiometry, it is also important to understand O diffusion. In order to better understand bulk Xe behavior in UO{sub 2{+-}x} we first calculate the relevant activation energies using DFT techniques. By analyzing a combination of Xe solution thermodynamics, migration barriers and the interaction of dissolved Xe atoms with U, we demonstrate that Xe diffusion predominantly occurs via a vacancy-mediated mechanism. Since Xe transport is closely related to diffusion of U vacancies, we have also studied the activation energy for this process. In order to explain the low value of 2.4 eV found for U migration from independent damage experiments (not thermal equilibrium) the presence of vacancy clusters must be included in the analysis. Next we investigate species transport on the (111) UO{sub 2} surface, which is motivated by the formation of small voids partially filled with fission gas atoms (bubbles) in UO{sub 2} under irradiation. Surface diffusion could be the rate-limiting step for diffusion of such bubbles, which is an alternative mechanism for mass transport in these materials. As expected, the activation energy for surface diffusion is significantly lower than for bulk transport. These results are further discussed in terms of engineering-scale fission gas release models

  7. A theoretical study on the effect of surface roughness on mass transport and transformation in biofilms.

    PubMed

    Picioreanu, C; van Loosdrecht, M C; Heijnen, J J

    2000-05-20

    This modeling study evaluates the influence of biofilm geometrical characteristics on substrate mass transfer and conversion rates. A spatially two-dimensional model was used to compute laminar fluid flow, substrate mass transport, and conversion in irregularly shaped biofilms. The flow velocity above the biofilm surface was varied over 3 orders of magnitude. Numerical results show that increased biofilm roughness does not necessarily lead to an enhancement of either conversion rates or external mass transfer. The average mass transfer coefficient and Sherwood numbers were found to decrease almost linearly with biofilm area enlargement in the flow regime tested. The influence of flow, biofilm geometry and biofilm activity on external mass transfer could be quantified by Sh-Re correlations. The effect of biofilm surface roughness was incorporated in this correlation via area enlargement. Conversion rates could be best correlated to biofilm compactness. The more compact the biofilm, the higher the global conversion rate of substrate. Although an increase of bulk fluid velocity showed a large effect on mass transfer coefficients, the global substrate conversion rate per carrier area was less affected. If only diffusion occurs in pores and channels, then rough biofilms behave as if they were compact but having less biomass activity. In spite of the fact that the real biofilm area is increased due to roughness, the effective mass transfer area is actually decreased because only biofilm peaks receive substrate. This can be explained by the fact that in the absence of normal convection in the biofilm valleys, the substrate gradients are still largely perpendicular to the carrier. Even in the cases where convective transport dominates the external mass transfer process, roughness could lead to decreased conversion rates. The results of this study clearly indicate that only evaluation of overall conversion rates or mass fluxes can describe the correct biofilm conversion

  8. Multigrid optimal mass transport for image registration and morphing

    NASA Astrophysics Data System (ADS)

    Rehman, Tauseef ur; Tannenbaum, Allen

    2007-02-01

    In this paper we present a computationally efficient Optimal Mass Transport algorithm. This method is based on the Monge-Kantorovich theory and is used for computing elastic registration and warping maps in image registration and morphing applications. This is a parameter free method which utilizes all of the grayscale data in an image pair in a symmetric fashion. No landmarks need to be specified for correspondence. In our work, we demonstrate significant improvement in computation time when our algorithm is applied as compared to the originally proposed method by Haker et al [1]. The original algorithm was based on a gradient descent method for removing the curl from an initial mass preserving map regarded as 2D vector field. This involves inverting the Laplacian in each iteration which is now computed using full multigrid technique resulting in an improvement in computational time by a factor of two. Greater improvement is achieved by decimating the curl in a multi-resolutional framework. The algorithm was applied to 2D short axis cardiac MRI images and brain MRI images for testing and comparison.

  9. Mass and charge transport in IPMC actuators with fractal interfaces

    NASA Astrophysics Data System (ADS)

    Chang, Longfei; Wu, Yucheng; Zhu, Zicai; Li, Heng

    2016-04-01

    Ionic Polymer-Metal Composite (IPMC) actuators have been attracting a growing interest in extensive applications, which consequently raises the demands on the accuracy of its theoretical modeling. For the last few years, rough landscape of the interface between the electrode and the ionic membrane of IPMC has been well-documented as one of the key elements to ensure a satisfied performance. However, in most of the available work, the interface morphology of IPMC was simplified with structural idealization, which lead to perplexity in the physical interpretation on its interface mechanism. In this paper, the quasi-random rough interface of IPMC was described with fractal dimension and scaling parameters. And the electro-chemical field was modeled by Poisson equation and a properly simplified Nernst-Planck equation set. Then, by simulation with Finite Element Method, a comprehensive analysis on he inner mass and charge transportation in IPMC actuators with different fractal interfaces was provided, which may be further adopted to instruct the performance-oriented interface design for ionic electro-active actuators. The results also verified that rough interface can impact the electrical and mechanical response of IPMC, not only from the respect of the real surface increase, but also from mass distribution difference caused by the complexity of the micro profile.

  10. Mass transport and element mobilisation during large-scale metasomatism

    NASA Astrophysics Data System (ADS)

    Putnis, C. V.; Austrheim, H.; Jamtveit, B.; Engvik, A. K.; Putnis, A.

    2009-04-01

    Replacement textures commonly occur in relation to fluid-driven large scale metasomatism and metamorphism and these processes are often related to mineralisation. For example, the albitisation of gabbroic rocks in the Bamble District, southern Norway is associated with ore deposits. Similar albitised rocks are also characteristic of the Curnamona Province, Australia, which includes large areas of mineralisation such as the Pb, Zn, Ag of the Broken Hill deposits as well as Cu, Au and U deposits. The main question addressed here is the mechanism of mass transport and hence element mobilisation. An indication of the former presence of fluids within a rock can be seen in mineral textures, such as porosity, replacement rims, replacement induced fracturing and crystallographic continuity across sharp compositional boundaries. Such textural observations from natural rocks as well as experimental products show that during mineral-fluid interaction, the crystallographic relations between parent and product phases control the nucleation of the product, and hence a coupling between dissolution and reprecipitation. If the rate of nucleation and growth of the product equals the dissolution rate, a pseudomorphic replacement takes place. The degree of epitaxy (or lattice misfit) at the interface, the relative solubility of parent and product phases and the molar volume changes control the microstructure of the product phase. The key observation is that these factors control the generation of porosity as well as reaction induced fracturing ahead of the main reaction interface. Porosity is generated whenever the amount of parent dissolved is greater than the amount of product reprecipitated, irrespective of the molar volume changes of the solid reactants and products. This porosity is occupied by the fluid phase during the reaction, and provides a mechanism of mass transport and fluid movement between reaction interface and the surrounding phases. The reaction-induced fracturing

  11. Accurate measurement of liquid transport through nanoscale conduits

    PubMed Central

    Alibakhshi, Mohammad Amin; Xie, Quan; Li, Yinxiao; Duan, Chuanhua

    2016-01-01

    Nanoscale liquid transport governs the behaviour of a wide range of nanofluidic systems, yet remains poorly characterized and understood due to the enormous hydraulic resistance associated with the nanoconfinement and the resulting minuscule flow rates in such systems. To overcome this problem, here we present a new measurement technique based on capillary flow and a novel hybrid nanochannel design and use it to measure water transport through single 2-D hydrophilic silica nanochannels with heights down to 7 nm. Our results show that silica nanochannels exhibit increased mass flow resistance compared to the classical hydrodynamics prediction. This difference increases with decreasing channel height and reaches 45% in the case of 7 nm nanochannels. This resistance increase is attributed to the formation of a 7-angstrom-thick stagnant hydration layer on the hydrophilic surfaces. By avoiding use of any pressure and flow sensors or any theoretical estimations the hybrid nanochannel scheme enables facile and precise flow measurement through single nanochannels, nanotubes, or nanoporous media and opens the prospect for accurate characterization of both hydrophilic and hydrophobic nanofluidic systems. PMID:27112404

  12. Accurate measurement of liquid transport through nanoscale conduits

    NASA Astrophysics Data System (ADS)

    Alibakhshi, Mohammad Amin; Xie, Quan; Li, Yinxiao; Duan, Chuanhua

    2016-04-01

    Nanoscale liquid transport governs the behaviour of a wide range of nanofluidic systems, yet remains poorly characterized and understood due to the enormous hydraulic resistance associated with the nanoconfinement and the resulting minuscule flow rates in such systems. To overcome this problem, here we present a new measurement technique based on capillary flow and a novel hybrid nanochannel design and use it to measure water transport through single 2-D hydrophilic silica nanochannels with heights down to 7 nm. Our results show that silica nanochannels exhibit increased mass flow resistance compared to the classical hydrodynamics prediction. This difference increases with decreasing channel height and reaches 45% in the case of 7 nm nanochannels. This resistance increase is attributed to the formation of a 7-angstrom-thick stagnant hydration layer on the hydrophilic surfaces. By avoiding use of any pressure and flow sensors or any theoretical estimations the hybrid nanochannel scheme enables facile and precise flow measurement through single nanochannels, nanotubes, or nanoporous media and opens the prospect for accurate characterization of both hydrophilic and hydrophobic nanofluidic systems.

  13. Accurate measurement of liquid transport through nanoscale conduits.

    PubMed

    Alibakhshi, Mohammad Amin; Xie, Quan; Li, Yinxiao; Duan, Chuanhua

    2016-01-01

    Nanoscale liquid transport governs the behaviour of a wide range of nanofluidic systems, yet remains poorly characterized and understood due to the enormous hydraulic resistance associated with the nanoconfinement and the resulting minuscule flow rates in such systems. To overcome this problem, here we present a new measurement technique based on capillary flow and a novel hybrid nanochannel design and use it to measure water transport through single 2-D hydrophilic silica nanochannels with heights down to 7 nm. Our results show that silica nanochannels exhibit increased mass flow resistance compared to the classical hydrodynamics prediction. This difference increases with decreasing channel height and reaches 45% in the case of 7 nm nanochannels. This resistance increase is attributed to the formation of a 7-angstrom-thick stagnant hydration layer on the hydrophilic surfaces. By avoiding use of any pressure and flow sensors or any theoretical estimations the hybrid nanochannel scheme enables facile and precise flow measurement through single nanochannels, nanotubes, or nanoporous media and opens the prospect for accurate characterization of both hydrophilic and hydrophobic nanofluidic systems. PMID:27112404

  14. A Mercury Transport and Fate Model for Mass Budget Assessment of Mercury Cycling in Lake Michigan

    EPA Science Inventory

    A mercury mass balance model was developed to describe and evaluate the fate, transport, and biogeochemical transformations of mercury in Lake Michigan. Coupling with total suspendable solids (TSS) and dissolved organic carbon (DOC), the mercury transport and fate model simulates...

  15. Estimating kinetic mass transfer by resting-period measurements in flow-interruption tracer tests

    SciTech Connect

    Gong, R; Lu, C; Wu, Wei-min; Cheng, H.; Gu, Baohua; Watson, David B; Criddle, Craig; Kitanidis, Peter K.; Brooks, Scott C; Jardine, Philip M; Luo, Jian

    2010-06-01

    Flow-interruption tracer test is an effective approach to identify kinetic mass transfer processes for solute transport in subsurface media. By switching well pumping and resting, one may alter the dominant transport mechanism and generate special concentration patterns for identifying kinetic mass transfer processes. In the present research, we conducted three-phase (i.e., pumping, resting, and pumping) field-scale flow-interruption tracer tests using a conservative tracer bromide in a multiple-well system installed at the US Department of Energy Site, Oak Ridge, TN. A novel modeling approach based on the resting-period measurements was developed to estimate the mass transfer parameters. This approach completely relied on the measured breakthrough curves without requiring detailed aquifer characterization and solving transport equations in nonuniform, transient flow fields. Additional measurements, including hydraulic heads and tracer concentrations in large pumping wells, were taken to justify the assumption that mass transfer processes dominated concentration change during resting periods. The developed approach can be conveniently applied to any linear mass transfer model. Both first-order and multirate mass transfer models were applied to analyze the breakthrough curves at various monitoring wells. The multirate mass transfer model was capable of jointly fitting breakthrough curve behavior, showing the effectiveness and flexibility for incorporating aquifer heterogeneity and scale effects in upscaling effective mass transfer models.

  16. Estimating kinetic mass transfer by resting-period measurements in flow-interruption tracer tests.

    PubMed

    Gong, R; Lu, C; Wu, W-M; Cheng, H; Gu, B; Watson, D B; Criddle, C S; Kitanidis, P K; Brooks, S C; Jardine, P M; Luo, J

    2010-09-20

    Flow-interruption tracer test is an effective approach to identify kinetic mass transfer processes for solute transport in subsurface media. By switching well pumping and resting, one may alter the dominant transport mechanism and generate special concentration patterns for identifying kinetic mass transfer processes. In the present research, we conducted three-phase (i.e., pumping, resting, and pumping) field-scale flow-interruption tracer tests using a conservative tracer bromide in a multiple-well system installed at the US Department of Energy Site, Oak Ridge, TN. A novel modeling approach based on the resting-period measurements was developed to estimate the mass transfer parameters. This approach completely relied on the measured breakthrough curves without requiring detailed aquifer characterization and solving transport equations in nonuniform, transient flow fields. Additional measurements, including hydraulic heads and tracer concentrations in large pumping wells, were taken to justify the assumption that mass transfer processes dominated concentration change during resting periods. The developed approach can be conveniently applied to any linear mass transfer model. Both first-order and multirate mass transfer models were applied to analyze the breakthrough curves at various monitoring wells. The multirate mass transfer model was capable of jointly fitting breakthrough curve behavior, showing the effectiveness and flexibility for incorporating aquifer heterogeneity and scale effects in upscaling effective mass transfer models.

  17. Measurement of hydrocarbon transport in bacteria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the hydrophobic, volatility, and relatively low aqueous solubility of aliphatic and aromatic hydrocarbons, transport of these chemicals by bacteria has not been extensively studied. These issues make transport assays difficult to carry out, and as a result, strong evidence for the active tran...

  18. Measurement of Hydrocarbon Transport in Bacteria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydrocarbon uptake by bacteria has not been extensively studied, and strong evidence for active transport of hydrocarbons is lacking. The volatile nature of hydrocarbons, their hydrophobicity, and their relatively low aqueous solubilities can complicate transport assays. Here we present a detailed...

  19. TRANSPORT PROPERTY MEASUREMENTS OF HFC-236EA

    EPA Science Inventory

    The report gives results of an evaluation of transport properties of 1,1,1,2,3,3,-hexafluoropropane (HFC-236ea), with liquid viscosity and thermal conductivity being the two main transport properties of interest. In addition, the specific heat and density of refrigerant/lubrican...

  20. Experimental validation of convection-diffusion discretisation scheme employed for computational modelling of biological mass transport

    PubMed Central

    2010-01-01

    Background The finite volume solver Fluent (Lebanon, NH, USA) is a computational fluid dynamics software employed to analyse biological mass-transport in the vasculature. A principal consideration for computational modelling of blood-side mass-transport is convection-diffusion discretisation scheme selection. Due to numerous discretisation schemes available when developing a mass-transport numerical model, the results obtained should either be validated against benchmark theoretical solutions or experimentally obtained results. Methods An idealised aneurysm model was selected for the experimental and computational mass-transport analysis of species concentration due to its well-defined recirculation region within the aneurysmal sac, allowing species concentration to vary slowly with time. The experimental results were obtained from fluid samples extracted from a glass aneurysm model, using the direct spectrophometric concentration measurement technique. The computational analysis was conducted using the four convection-diffusion discretisation schemes available to the Fluent user, including the First-Order Upwind, the Power Law, the Second-Order Upwind and the Quadratic Upstream Interpolation for Convective Kinetics (QUICK) schemes. The fluid has a diffusivity of 3.125 × 10-10 m2/s in water, resulting in a Peclet number of 2,560,000, indicating strongly convection-dominated flow. Results The discretisation scheme applied to the solution of the convection-diffusion equation, for blood-side mass-transport within the vasculature, has a significant influence on the resultant species concentration field. The First-Order Upwind and the Power Law schemes produce similar results. The Second-Order Upwind and QUICK schemes also correlate well but differ considerably from the concentration contour plots of the First-Order Upwind and Power Law schemes. The computational results were then compared to the experimental findings. An average error of 140% and 116% was demonstrated

  1. Mass transport, faceting and behavior of dislocations in GaN

    SciTech Connect

    Nitta, S.; Kashima, T.; Kariya, M.; Yukawa, Y.; Yamaguchi, S.; Amano, H.; Akasaki, I.

    2000-07-01

    The behavior of threading dislocations during mass transport of GaN was investigated in detail by transmission electron microscopy. Mass transport occurred at the surface. Therefore, growing species are supplied from the in-plane direction. The behavior of threading dislocations was found to be strongly affected by the mass transport process as well as the high crystallographic anisotropy of the surface energy of the facets particular to GaN.

  2. The latent fingerprint in mass transport of polycrystalline materials

    NASA Astrophysics Data System (ADS)

    Thirunavukarasu, Gopinath; Kundu, Sukumar; Chatterjee, Subrata

    2016-02-01

    Herein, a systematic investigation was carried out to reach a rational understanding and to provide information concerning the possible causes for a significant influence of pressure variation in the underlying processes of mass transport in polycrystalline materials. The authors focused their research in solid-state diffusion, a part of the subject "Mass Transport in Solids". Theories on diffusion are the subject by itself which exists as a latent fingerprint in every text of higher learning in interdisciplinary science. In this research, authors prepared sandwich samples of titanium alloy and stainless steel using nickel as an intermediate metal. The samples were processed at three different levels of bonding pressure (3, 4 and 5 MPa) while bonding temperature and bonding time was maintained at 750 °C and 1 h, respectively, throughout the experiments. It was observed that the net flux of atomic diffusion of nickel atoms into Ti-alloy at TiA/Ni interface increased by ~63 % with the rise in the bonding pressure from 3 to 4 MPa, but decreased by ~40 % with the rise in the bonding pressure from 4 to 5 MPa. At the same time, the net flux of atomic diffusion of nickel atoms into stainless steel at Ni/SS interface increased by ~19 % with the rise in the bonding pressure from 3 to 4 MPa, but increased by ~17 % with the rise in the bonding pressure from 4 to 5 MPa. Here authors showed that the pressure variations have different effects at the TiA/Ni interface and Ni/SS interface, and tried to explain the explicit mechanisms operating behind them. In general for sandwich samples processed irrespective of bonding pressure chosen, the net flux of Ni-atoms diffused into SS is greater than that of the net flux of Ni-atoms diffused in Ti-alloy matrix by four orders of magnitude. The calculated diffusivity of Ni-atoms into Ti-alloy reaches its highest value of ~5.083 × 10-19 m2/s for the sandwich sample processed using 4-MPa bonding-pressure, whereas the diffusivity of Ni

  3. Conception for enhanced mass transport in binary nanofluids

    NASA Astrophysics Data System (ADS)

    Xuan, Yimin

    2009-12-01

    Besides their application in enhancing heat transfer, suspended nanoparticles have been found to improve mass transfer process inside binary nanofluids. The concepts of enhanced mass transfer in binary nanofluids are involved. By means of the heat and mass transfer analogy, the approaches for determining the mass diffusivity and mass transfer coefficient are proposed and discussed.

  4. Mass measurements along the r-process path at CARIBU

    NASA Astrophysics Data System (ADS)

    Savard, Guy; Clark, Jason; van Schelt, Jon; Lascar, Dan; Levand, Anthony; Zabransky, Bruce; Sharma, Kumar

    2012-10-01

    The CARIBU facility is now operational and a large body of new mass measurements around the N=82 waiting point has been accumulated. The masses of over 70 neutron-rich isotopes from the heavy Californium fission peak have been measured with the CPT Penning trap mass spectrometer yielding a typical accuracy of 10 keV/c2. The most neutron-rich masses show significant deviations from either masses measured by other means when available or from extrapolated values from the last Atomic Mass Evaluation when no measurements where available. The system used for these measurements will be briefly described and an analysis of the modification to the delay for the r-process in this region when taking into accounts the new masses will be presented.

  5. Modeling Transport of Secondary Ion Fragments into a Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Warmenhoven, J.; Demarche, J.; Palitsin, V.; Kirkby, K. J.; Webb, R. P.

    The Surrey Ion Beam Centre was awarded the Engineering and Physical Sciences Research Council (EPSRC) grant for "Promoting Cross Disciplinary Research: Engineering and Physical Sciences and Social Sciences" allowing continued research into the characteristics of desorption of secondary ions by the impact of fast primary ions in the ambient pressure at the sub-micron scale. To carry out this research a new beamline has been constructed consisting of a time-of-flight secondary ion mass spectrometer combined with the current 2MV Tandem accelerator. This research has already returned many significant results such as the first simultaneous SIMS, PIXE and RBS measurement preformed on an organic sample in vacuum. However, further optimization and validation of the new beamline is still being worked on. This work focuses on the optimization of the end station geometry to allow for high sensitivity ambient pressure measurements. It is concluded that a common geometry can be adopted for a wide variety of smooth samples to ensure optimum sensitivity provided a hard edge of the sample can be found to place the mass spectrometer capillary near.

  6. Mass transport model through the skin by microencapsulation system.

    PubMed

    Carreras, Núria; Alonso, Cristina; Martí, Meritxell; Lis, Manel J

    2015-01-01

    Skin drug delivery can be subdivided into topical and transdermal administration. Transdermal administration can take advantage of chemical and physical strategies that can improve skin permeability and allow drug penetration. In this study, the development of a skin penetration profile was carried out by an in vitro technique for a microencapsulated system of ibuprofen. Release experiments were performed using percutaneous absorption tests to determine the evolution of the principle present in each of the different skin compartments as a function of time. A general kinetic model for a microencapsulated structure as a mass transport system through the skin was applied: [Formula: see text] This model could predict the penetration profile of encapsulated substances through skin from biofunctional textiles as well as estimate the dosage profile of the active principle. The apparent diffusion coefficients found were 1.20 × 10(-7 )cm/s for the stratum corneum and higher for the rest of the skin 6.67 × 10(-6 )cm/s. PMID:26004367

  7. Development of the Vortex Mass Flowmeter with Wall Pressure Measurement

    NASA Astrophysics Data System (ADS)

    Li, Zhiyong; Sun, Zhiqiang

    2013-01-01

    Mass flow measurement is essential to the understanding and control of processes concerning fluid flow. The availability of reliable mass flowmeters, however, is far inadequate to meet the demand. In this paper we developed a practical vortex mass flowmeter with wall pressure measurement. The meter coefficient of mass flow rate was acquired through experiments with air at Reynolds numbers from 1.3×103 to 9.8×103. Here we show that the meter coefficient of mass flow rate is nearly constant at Reynolds numbers greater than 5.5×103. To further extend the lower limit, a correction factor related to the Reynolds number was introduced into the vortex mass flowmeter. The results show that the relative errors of the vortex mass flowmeter developed are basically within ±5%. This device can satisfy a diversity of requirements of mass flow measurement in engineering fields.

  8. Mass spectrometric measurements of the isotopic anatomies of molecules (Invited)

    NASA Astrophysics Data System (ADS)

    Eiler, J. M.; Krumwiede, D.; Schlueter, H.

    2013-12-01

    Site-specific and multiple isotopic substitutions in molecular structures potentially provide an extraordinarily rich set of constraints on their sources, conditions of formation, reaction and transport histories, and perhaps other issues. Examples include carbonate ';clumped isotope' thermometry, clumped isotope measurements of CO2, O2, and, recently, methane, ethane and N2O; site-specific 15N measurements in N2O and 13C and D analyses of fatty acids, sugars, cellulose, food products, and, recently, n-alkanes. Extension of the principles behind these tools to the very large number of isotopologues of complex molecules could potentially lead to new uses of isotope chemistry, similar to proteomics, metabolomics and genomics in their complexity and depth of detail (';isotomics'?). Several technologies are potentially useful for this field, including ';SNIF-NMR', gas source mass spectrometry and IR absorption spectroscopy. However, all well established methods have restrictive limits in the sizes of samples, types of analyzes, and the sorts of isotopologues that can be measured with useful precision. We will present an overview of several emerging instruments and techniques of high-resolution gas source mass spectrometry that may enable study of a large proportion of the isotopologues of a wide range of volatile and semi-volatile compounds, including many organics, with precisions and sample sizes suitable for a range of applications. A variety of isotopologues can be measured by combining information from the Thermo 253 Ultra (a new high resolution, multi-collector gas source mass spectrometer) and the Thermo DFS (a very high resolution single collector, but used here on a novel mode to achieve ~per mil precision ratio measurements), sometimes supplemented by conventional bulk isotopic measurements. It is possible to design methods in which no one of these sources of data meaningfully constrain abundances of specific isotopologues, but their combination fully and

  9. Innovative mechanism for measuring the mass properties of an object

    NASA Technical Reports Server (NTRS)

    Wolcott, Kedron R.; Graham, Todd A.; Doty, Keith L.

    1994-01-01

    The Kennedy Space Center Robotics Group recently completed development and testing on a novel approach to measure the mass properties of a rigid body. This unique design can measure the payload's weight, mass center location, and moments of inertia about three orthogonal axes. Furthermore, these measurements only require a single torque sensor and a single angular position sensor.

  10. Theoretical monochromatic-wave-induced currents in intermediate water with viscosity and nonzero mass transport

    NASA Technical Reports Server (NTRS)

    Talay, T. A.

    1975-01-01

    Wave-induced mass-transport current theories with both zero and nonzero net mass (or volume) transport of the water column are reviewed. A relationship based on the Longuet-Higgens theory is derived for wave-induced, nonzero mass-transport currents in intermediate water depths for a viscous fluid. The relationship is in a form useful for experimental applications; therefore, some design criteria for experimental wave-tank tests are also presented. Sample parametric cases for typical wave-tank conditions and a typical ocean swell were assessed by using the relation in conjunction with an equation developed by Unluata and Mei for the maximum wave-induced volume transport. Calculations indicate that substantial changes in the wave-induced mass-transport current profiles may exist dependent upon the assumed net volume transport. A maximum volume transport, corresponding to an infinite channel or idealized ocean condition, produces the largest wave-induced mass-transport currents. These calculations suggest that wave-induced mass-transport currents may have considerable effects on pollution and suspended-sediments transport as well as buoy drift, the surface and midlayer water-column currents caused by waves increasing with increasing net volume transports. Some of these effects are discussed.

  11. New Directions in Mass Communications Research: Physiological Measurement.

    ERIC Educational Resources Information Center

    Fletcher, James E.

    Psychophysiological research into the effects of mass media, specifically the music of the masses, promises increased insight into the control the media exert on all their consumers. Attention and retention of mass media messages can be tested by measuring the receiver's electrodernal activity, pupil dilation, peripheral vasodilation, and heart…

  12. High precision mass measurements for wine metabolomics

    NASA Astrophysics Data System (ADS)

    Roullier-Gall, Chloé; Witting, Michael; Gougeon, Régis; Schmitt-Kopplin, Philippe

    2014-11-01

    An overview of the critical steps for the non-targeted Ultra-High Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Mass Spectrometry (UPLC-Q-ToF-MS) analysis of wine chemistry is given, ranging from the study design, data preprocessing and statistical analyses, to markers identification. UPLC-Q-ToF-MS data was enhanced by the alignment of exact mass data from FTICR-MS, and marker peaks were identified using UPLC-Q-ToF-MS². In combination with multivariate statistical tools and the annotation of peaks with metabolites from relevant databases, this analytical process provides a fine description of the chemical complexity of wines, as exemplified in the case of red (Pinot noir) and white (Chardonnay) wines from various geographic origins in Burgundy.

  13. High precision mass measurements for wine metabolomics

    PubMed Central

    Roullier-Gall, Chloé; Witting, Michael; Gougeon, Régis D.; Schmitt-Kopplin, Philippe

    2014-01-01

    An overview of the critical steps for the non-targeted Ultra-High Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Mass Spectrometry (UPLC-Q-ToF-MS) analysis of wine chemistry is given, ranging from the study design, data preprocessing and statistical analyses, to markers identification. UPLC-Q-ToF-MS data was enhanced by the alignment of exact mass data from FTICR-MS, and marker peaks were identified using UPLC-Q-ToF-MS2. In combination with multivariate statistical tools and the annotation of peaks with metabolites from relevant databases, this analytical process provides a fine description of the chemical complexity of wines, as exemplified in the case of red (Pinot noir) and white (Chardonnay) wines from various geographic origins in Burgundy. PMID:25431760

  14. First Penning Trap Mass Measurements beyond the Proton Drip Line

    SciTech Connect

    Rauth, C.; Ackermann, D.; Block, M.; Herfurth, F.; Hessberger, F. P.; Kluge, H.-J.; Maero, G.; Martin, A.; Mukherjee, M.; Rahaman, S.; Blaum, K.; Ferrer, R.; Chaudhuri, A.; Marx, G.; Schweikhard, L.; Di, Z.; Plass, W. R.; Eliseev, S.; Vorobjev, G.; Habs, D.

    2008-01-11

    The masses of six neutron-deficient rare holmium and thulium isotopes close to the proton drip line were determined with the SHIPTRAP Penning trap mass spectrometer. For the first time the masses of the proton-unbound isotopes {sup 144,145}Ho and {sup 147,148}Tm were directly measured. The proton separation energies were derived from the measured mass values and compared to predictions from mass formulas. The new values of the proton separation energies are used to determine the location of the proton drip line for holmium and thulium more accurately.

  15. Oligomers Modulate Interfibril Branching and Mass Transport Properties of Collagen Matrices

    PubMed Central

    Whittington, Catherine F.; Brandner, Eric; Teo, Ka Yaw; Han, Bumsoo; Nauman, Eric; Voytik-Harbin, Sherry L.

    2013-01-01

    Mass transport within collagen-based matrices is critical to tissue development, repair, and pathogenesis as well as the design of next generation tissue engineering strategies. This work shows how collagen precursors, specified by intermolecular cross-link composition, provide independent control of collagen matrix mechanical and transport properties. Collagen matrices were prepared from tissue-extracted monomers or oligomers. Viscoelastic behavior was measured in oscillatory shear and unconfined compression. Matrix permeability and diffusivity were measured using gravity-driven permeametry and integrated optical imaging, respectively. Both collagen types showed an increase in stiffness and permeability hindrance with increasing collagen concentration (fibril density); however, different physical property-concentration relationships were noted. Diffusivity wasn’t affected by concentration for either collagen type over the range tested. In general, oligomer matrices exhibited a substantial increase in stiffness and only a modest decrease in transport properties when compared to monomer matrices prepared at the same concentration. The observed differences in viscoelastic and transport properties were largely attributed to increased levels of interfibril branching within oligomer matrices. The ability to relate physical properties to relevant microstructure parameters, including fibril density and interfibril branching, is expected to advance the understanding of cell-matrix signaling as well as facilitate model-based prediction and design of matrix-based therapeutic strategies. PMID:23842082

  16. Overview of mitigation policies and measures in transportation

    SciTech Connect

    Ernst, J.

    1996-12-31

    In this paper the author looks at the general question of what can be done in the transportation sector to address the problem of greenhouse gas emissions. Obviously, fewer vehicles is less emission. But on a global scale he reviews the population growth in major cities, the type of transport employed, the correlation of vehicle ownership and gross national product, as well as the costs, direct and indirect of letting more personal wealth drive one to personal vehicles as a way to transport oneself to work. The increased speed comes with many costs for the individual and for society. The development of mass transportation systems provides a number of benefits, in the form of urban development, less reliance on imported fuels, transport system health, general health and productivity of work force, and reduced costs to government to support transportation systems.

  17. Estimation of water table level and nitrate pollution based on geostatistical and multiple mass transport models

    NASA Astrophysics Data System (ADS)

    Matiatos, Ioannis; Varouhakis, Emmanouil A.; Papadopoulou, Maria P.

    2015-04-01

    As the sustainable use of groundwater resources is a great challenge for many countries in the world, groundwater modeling has become a very useful and well established tool for studying groundwater management problems. Based on various methods used to numerically solve algebraic equations representing groundwater flow and contaminant mass transport, numerical models are mainly divided into Finite Difference-based and Finite Element-based models. The present study aims at evaluating the performance of a finite difference-based (MODFLOW-MT3DMS), a finite element-based (FEFLOW) and a hybrid finite element and finite difference (Princeton Transport Code-PTC) groundwater numerical models simulating groundwater flow and nitrate mass transport in the alluvial aquifer of Trizina region in NE Peloponnese, Greece. The calibration of groundwater flow in all models was performed using groundwater hydraulic head data from seven stress periods and the validation was based on a series of hydraulic head data for two stress periods in sufficient numbers of observation locations. The same periods were used for the calibration of nitrate mass transport. The calibration and validation of the three models revealed that the simulated values of hydraulic heads and nitrate mass concentrations coincide well with the observed ones. The models' performance was assessed by performing a statistical analysis of these different types of numerical algorithms. A number of metrics, such as Mean Absolute Error (MAE), Root Mean Square Error (RMSE), Bias, Nash Sutcliffe Model Efficiency (NSE) and Reliability Index (RI) were used allowing the direct comparison of models' performance. Spatiotemporal Kriging (STRK) was also applied using separable and non-separable spatiotemporal variograms to predict water table level and nitrate concentration at each sampling station for two selected hydrological stress periods. The predictions were validated using the respective measured values. Maps of water table

  18. Finding the Density of Objects without Measuring Mass and Volume

    ERIC Educational Resources Information Center

    Mumba, Frackson; Tsige, Mesfin

    2007-01-01

    A simple method based on the moment of forces and Archimedes' principle is described for finding density without measuring the mass and volume of an object. The method involves balancing two unknown objects of masses M[subscript 1] and M[subscript 2] on each side of a pivot on a metre rule and measuring their corresponding moment arms. The object…

  19. Integrated mass transportation system study/definition/implementation program definition

    NASA Technical Reports Server (NTRS)

    Ransone, R. K.; Deptula, D. A.; Yorke, G. G.

    1975-01-01

    Specific actions needed to plan and effect transportation system improvements are identified within the constraints of limited financial, energy and land use resources, and diverse community requirements. A specific program is described which would develop the necessary generalized methodology for devising improved transportation systems and evaluate them against specific criteria for intermodal and intramodal optimization. A consistent, generalized method is provided for study and evaluation of transportation system improvements.

  20. Appropriate burnup measurements for transportation burnup credit

    SciTech Connect

    Lancaster, D.; Fuentes, E.

    1997-04-01

    This paper addresses two of the measurement specifications used in analyzing spent fuel packages to gain burnup credit. The philosophy and calculation of rejection criteria and measurement accuracy are discussed. Any assembly for which the declared measured value and reactor record value deviate by more than 10% will be rejected. Measurement accuracy requirements are established for dependent and independent systems. The requirements have been tested and are achievable, ensuring safe operation without extra cost. 6 refs.

  1. Glacier mass budget measurements by hydrologic means

    USGS Publications Warehouse

    Tangborn, Wendell V.

    1966-01-01

    Ice storage changes for the South Cascade Glacier drainage basin were determined for the 1957–1964 period using basin runoff and precipitation measurements. Measurements indicate that evaporation and condensation are negligible compared with the large runoff and precipitation values. Runoff, measured by a stream discharge station, averaged 4.04 m/yr; precipitation, determined by snow accumulation measurements at a central point on the glacier and by storage gages, averaged 3.82 m/yr, resulting in a basin net loss of about 0.22 m/yr. During the same period, South Cascade Glacier net budgets were determined by ablation stakes, snow density-depth profiles, and maps. The average glacier net budget for the period was −0.61sol;yr of water. This amount is equivalent to −0.26 m of water when averaged over the drainage basin (43% glacier-covered), which is in fair agreement with the net storage change measured by hydrologic methods. Agreement between the two methods for individual years is slightly less perfect. (Key words: Glaciers; water balance.)

  2. Variation of bedload transport threshold in two Alpine mountain streams inferred from geophone measurements

    NASA Astrophysics Data System (ADS)

    Rickenmann, Dieter; Weninger, Thomas

    2015-04-01

    Geophone measurements are a surrogate technique to monitor bedload transport in mountain streams. The two mountain streams Fischbach and the Ruetz in Western Austria are fed by glacial meltwater and feature regular bedload transport during the summer months. In spring 2008 the so-called Swiss plate geophone system was installed in the two streams. The sites are operated by the Tyrolean water power company (TIWAG), and discharge data are available as well. The geophone sensors record the motion of bedload particles transported over a steel plate mounted flush with the channel bed. Calibration measurements of the geophone system were performed by TIWAG, and they show an approximately linear relation between number of impulses and bedload mass transported over the sensors. For the period 2008 to 2013, the variation in bedload transport with shear stress was analyzed using an exponential form of the Meyer-Peter & Müller equation proposed by Chen (2002). If the dimensionless threshold shear stress at initiation of motion, i.e. the Shields number, is back-calculated from the measured bedload transport rates, the temporal variability in bedload transport efficiency can be reasonably well described by postulating a corresponding temporal variability in the Shields number. The geophone measurements were also used to qualitatively assess the grain size distribution of the transported particles. It is hypothesized that an increase in the Shields number is associated with a coarsening of the surface grain size distribution of the bed material upstream of the measuring site.

  3. The photoinduced birefringence and mass transport in azo compound K-D-2

    NASA Astrophysics Data System (ADS)

    Klismeta, K.; Teteris, J.

    2015-06-01

    Azobenzene containing compounds are among light polarization sensitive materials - the moieties may align relative to the electric field vector of light, leading to anisotropy and birefringence in the sample. Another phenomenon which can be observed in azo compounds under influence of light is macroscopic movement of the material. In this work photoinduced processes in low molecular weight organic glass - bis-azobenzene containing compound K-D-2 were experimentally studied. Birefringence was induced with linearly polarized laser light (473, 532 and 635 nm) and measured at 633 nm wavelength. Polarization holography with recording beam configuration +45°/-45° was used to induce mass motion. Dependence of the surface relief depth on the recording laser wavelength in the visible spectrum (375 - 671 nm) was obtained. Formation of the SRG was observed with all used wavelengths and high birefringence values were obtained. Certain correlation between the absorption of the wavelength and photoinduced mass transport and birefringence is yet to be confirmed.

  4. Analysis of hemodynamic fluid phase mass transport in a separated flow region.

    PubMed

    Lutostansky, Elizabeth M; Karner, Gerhard; Rappitsch, Gerhard; Ku, David N; Perktold, Karl

    2003-04-01

    The mass transfer behavior in the recirculation region downstream of an axisymmetric sudden expansion was examined. The Reynolds number, 500, and Schmidt number, 3200, were selected to model the mass transfer of molecules, such as ADP, in the arterial system. In a first step the transient mass transport applying zero diffusive flux at the wall was analyzed using experiments and two computational codes. The two codes were FLUENT, a commercially available finite volume method, and FTSP, a finite element code developed at Graz University of Technology. The comparison of the transient wall concentration values determined by the three methods was excellent and provides a measure of confidence for computational mass transfer calculations in convection dominated, separated flows. In a second step the effect of the flow separation on the stationary mass transport applying a permeability boundary condition at the water-permeable wall was analyzed using the finite element code FTSP. The results show an increase of luminal ADP surface concentration in the upstream and in the downstream tube of the sudden expansion geometry in the range of six and twelve percent of the bulk flow concentration. The effect of flow separation in the downstream tube on the wall concentration is a decrease of about ten percent of the difference between wall concentration and bulk concentration occurring at nearly fully developed flow at the downstream region at a distance of 66 downstream tube diameters from the expansion. The decrease of ADP flux into the wall is in the range of three percent of the flux at the downstream region. PMID:12751280

  5. Dynamic Modeling Accuracy Dependence on Errors in Sensor Measurements, Mass Properties, and Aircraft Geometry

    NASA Technical Reports Server (NTRS)

    Grauer, Jared A.; Morelli, Eugene A.

    2013-01-01

    A nonlinear simulation of the NASA Generic Transport Model was used to investigate the effects of errors in sensor measurements, mass properties, and aircraft geometry on the accuracy of dynamic models identified from flight data. Measurements from a typical system identification maneuver were systematically and progressively deteriorated and then used to estimate stability and control derivatives within a Monte Carlo analysis. Based on the results, recommendations were provided for maximum allowable errors in sensor measurements, mass properties, and aircraft geometry to achieve desired levels of dynamic modeling accuracy. Results using other flight conditions, parameter estimation methods, and a full-scale F-16 nonlinear aircraft simulation were compared with these recommendations.

  6. Measurement of tracheal mucous transport rate in the horse

    SciTech Connect

    Nelson, R.; Hampe, D.W.

    1983-06-01

    Tracheal mucous transport rates were measured in 12 nonanesthetized horses after an intratracheal injection of 99mtechnetium-sulfur colloid. The transport rate of the subsequent bolus of radioactivity was determined, using a portable scaler rate meter fitted with a high-energy gamma-scintillation probe. A gamma-scintillation camera was used to verify bolus form and movement in 1 horse. The mean tracheal mucous transport rate was 1.66 +/- 0.24 cm/min.

  7. Influence and measurement of mass ablation in ICF implosions

    SciTech Connect

    Spears, B K; Hicks, D; Velsko, C; Stoyer, M; Robey, H; Munro, D; Haan, S; Landen, O; Nikroo, A; Huang, H

    2007-09-05

    Point design ignition capsules designed for the National Ignition Facility (NIF) currently use an x-ray-driven Be(Cu) ablator to compress the DT fuel. Ignition specifications require that the mass of unablated Be(Cu), called residual mass, be known to within 1% of the initial ablator mass when the fuel reaches peak velocity. The specifications also require that the implosion bang time, a surrogate measurement for implosion velocity, be known to +/- 50 ps RMS. These specifications guard against several capsule failure modes associated with low implosion velocity or low residual mass. Experiments designed to measure and to tune experimentally the amount of residual mass are being developed as part of the National Ignition Campaign (NIC). Tuning adjustments of the residual mass and peak velocity can be achieved using capsule and laser parameters. We currently plan to measure the residual mass using streaked radiographic imaging of surrogate tuning capsules. Alternative techniques to measure residual mass using activated Cu debris collection and proton spectrometry have also been developed. These developing techniques, together with bang time measurements, will allow us to tune ignition capsules to meet NIC specs.

  8. Mass measurements near the r-process path using the Canadian Penning Trap mass spectrometer

    NASA Astrophysics Data System (ADS)

    Van Schelt, J.; Lascar, D.; Savard, G.; Clark, J. A.; Caldwell, S.; Chaudhuri, A.; Fallis, J.; Greene, J. P.; Levand, A. F.; Li, G.; Sharma, K. S.; Sternberg, M. G.; Sun, T.; Zabransky, B. J.

    2012-04-01

    The masses of 40 neutron-rich nuclides from Z=51 to 64 were measured at an average precision of δm/m=10-7 using the Canadian Penning Trap mass spectrometer at Argonne National Laboratory. The measurements, of fission fragments from a 252Cf spontaneous fission source in a helium gas catcher, approach the predicted path of the astrophysical r process. Where overlap exists, this data set is largely consistent with previous measurements from Penning traps, storage rings, and reaction energetics, but large systematic deviations are apparent in β-endpoint measurements. Differences in mass excess from the 2003 Atomic Mass Evaluation of up to 400 keV are seen, as well as systematic disagreement with various mass models.

  9. CONVERGENCE STUDIES OF MASS TRANSPORT IN DISKS WITH GRAVITATIONAL INSTABILITIES. II. THE RADIATIVE COOLING CASE

    SciTech Connect

    Steiman-Cameron, Thomas Y.; Durisen, Richard H.; Michael, Scott; McConnell, Caitlin R.; Boley, Aaron C. E-mail: durisen@astro.indiana.edu E-mail: carmccon@indiana.edu

    2013-05-10

    We conduct a convergence study of a protoplanetary disk subject to gravitational instabilities (GIs) at a time of approximate balance between heating produced by the GIs and radiative cooling governed by realistic dust opacities. We examine cooling times, characterize GI-driven spiral waves and their resultant gravitational torques, and evaluate how accurately mass transport can be represented by an {alpha}-disk formulation. Four simulations, identical except for azimuthal resolution, are conducted with a grid-based three-dimensional hydrodynamics code. There are two regions in which behaviors differ as resolution increases. The inner region, which contains 75% of the disk mass and is optically thick, has long cooling times and is well converged in terms of various measures of structure and mass transport for the three highest resolutions. The longest cooling times coincide with radii where the Toomre Q has its minimum value. Torques are dominated in this region by two- and three-armed spirals. The effective {alpha} arising from gravitational stresses is typically a few Multiplication-Sign 10{sup -3} and is only roughly consistent with local balance of heating and cooling when time-averaged over many dynamic times and a wide range of radii. On the other hand, the outer disk region, which is mostly optically thin, has relatively short cooling times and does not show convergence as resolution increases. Treatment of unstable disks with optical depths near unity with realistic radiative transport is a difficult numerical problem requiring further study. We discuss possible implications of our results for numerical convergence of fragmentation criteria in disk simulations.

  10. A boundary element-Random walk model of mass transport in groundwater

    USGS Publications Warehouse

    Kemblowski, M.

    1986-01-01

    A boundary element solution to the convective mass transport in groundwater is presented. This solution produces a continuous velocity field and reduces the amount of data preparation time and bookkeeping. By combining this solution and the random walk procedure, a convective-dispersive mass transport model is obtained. This model may be easily used to simulate groundwater contamination problems. The accuracy of the boundary element model has been verified by reproducing the analytical solution to a two-dimensional convective mass transport problem. The method was also used to simulate a convective-dispersive problem. ?? 1986.

  11. The Kilogram and Measurements of Mass and Force

    PubMed Central

    Jabbour, Z. J.; Yaniv, S. L.

    2001-01-01

    This paper describes the facilities, measurement capabilities, and ongoing research activities in the areas of mass and force at the National Institute of Standards and Technology (NIST). The first section of the paper is devoted to mass metrology and starts with a brief historical perspective on the developments that led to the current definition of the kilogram. An overview of mass measurement procedures is given with a brief discussion of current research on alternative materials for mass standards and surface profiles of the U.S. national prototype kilograms. A brief outlook into the future possible redefinition of the unit of mass based on fundamental principles is included. The second part of this paper focuses on the unit of force and describes the realization of the unit, measurement procedures, uncertainty in the realized force, facilities, and current efforts aimed at the realization of small forces. PMID:27500016

  12. The Kilogram and Measurements of Mass and Force.

    PubMed

    Jabbour, Z J; Yaniv, S L

    2001-01-01

    This paper describes the facilities, measurement capabilities, and ongoing research activities in the areas of mass and force at the National Institute of Standards and Technology (NIST). The first section of the paper is devoted to mass metrology and starts with a brief historical perspective on the developments that led to the current definition of the kilogram. An overview of mass measurement procedures is given with a brief discussion of current research on alternative materials for mass standards and surface profiles of the U.S. national prototype kilograms. A brief outlook into the future possible redefinition of the unit of mass based on fundamental principles is included. The second part of this paper focuses on the unit of force and describes the realization of the unit, measurement procedures, uncertainty in the realized force, facilities, and current efforts aimed at the realization of small forces.

  13. Geocenter motion due to surface mass transport from GRACE satellite data

    NASA Astrophysics Data System (ADS)

    Riva, R. E. M.; van der Wal, W.; Lavallée, D. A.; Hashemi Farahani, H.; Ditmar, P.

    2012-04-01

    Measurements of mass redistribution from satellite gravimetry are insensitive to geocenter motions. However, geocenter motions can be constrained by satellite gravity data alone if we partition mass changes between land and oceans, under the assumption that the ocean is passive (i.e., in gravitational equilibrium with the land load and the solid earth). Here, we make use of 8 years (2003-2010) of optimally filtered monthly GRACE-based solutions produced at TU Delft to determine changes in the land load and the corresponding geocenter motion, through an iterative procedure. We pay particular attention to correcting for signal leakage caused by the limited spatial resolution of GRACE. We also investigate how the choice of a model of glacial isostatic adjustment (GIA) affects the estimated geocenter motion trend due to present-day surface mass transport. Finally, we separate the contribution of ice masses from that of land hydrology and show how they have a different sensitivity to the chosen GIA model and observational time-span.

  14. Evapotranspiration: Mass balance measurements compared with flux estimation methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evapotranspiration (ET) may be measured by mass balance methods and estimated by flux sensing methods. The mass balance methods are typically restricted in terms of the area that can be represented (e.g., surface area of weighing lysimeter (LYS) or equivalent representative area of neutron probe (NP...

  15. Subcontinuum mass transport of condensed hydrocarbons in nanoporous media

    PubMed Central

    Falk, Kerstin; Coasne, Benoit; Pellenq, Roland; Ulm, Franz-Josef; Bocquet, Lydéric

    2015-01-01

    Although hydrocarbon production from unconventional reservoirs, the so-called shale gas, has exploded recently, reliable predictions of resource availability and extraction are missing because conventional tools fail to account for their ultra-low permeability and complexity. Here, we use molecular simulation and statistical mechanics to show that continuum description—Darcy's law—fails to predict transport in shales nanoporous matrix (kerogen). The non-Darcy behaviour arises from strong adsorption in kerogen and the breakdown of hydrodynamics at the nanoscale, which contradict the assumption of viscous flow. Despite this complexity, all permeances collapse on a master curve with an unexpected dependence on alkane length. We rationalize this non-hydrodynamic behaviour using a molecular description capturing the scaling of permeance with alkane length and density. These results, which stress the need for a change of paradigm from classical descriptions to nanofluidic transport, have implications for shale gas but more generally for transport in nanoporous media. PMID:25901931

  16. Groundwater contamination: identification of source signal by time-reverse mass transport computation and filtering

    NASA Astrophysics Data System (ADS)

    Koussis, A. S.; Mazi, K.; Lykoudis, S.; Argyriou, A.

    2003-04-01

    Source signal identification is a forensic task, within regulatory and legal activities. Estimation of the contaminant's release history by reverse-solution (stepping back in time) of the mass transport equation, partialC/partialt + u partialC/partialx = D partial^2C/ partialx^2, is an ill-posed problem (its solution is non-unique and unstable). For this reason we propose the recovery of the source signal from measured concentration profile data through a numerical technique that is based on the premise of advection-dominated transport. We derive an explicit numerical scheme by discretising the pure advection equation, partialC/ partialt + u partial C/partialx = 0, such that it also models gradient-transport by matching numerical diffusion (leading truncation error term) to physical dispersion. The match is achieved by appropriate choice of the scheme’s spatial weighting coefficient q as function of the grid Peclet number P = u Δx/D: θ = 0.5 - P-1. This is a novel and efficient direct solution approach for the signal identification problem at hand that can accommodate space-variable transport parameters as well. First, we perform numerical experiments to define proper grids (in terms of Courant {bf C} = uΔt/Δx and grid Peclet P numbers) for control of spurious oscillations (instability). We then assess recovery of source signals, from perfect as well as from error-seeded field data, considering field data resulting from single- and double-peaked source signals. With perfect data, the scheme recovers source signals with very good accuracy. With imperfect data, however, additional data conditioning is required for control of signal noise. Alternating reverse profile computation with Savitzky-Golay low-pass filtering allows the recovery of well-timed and smooth source signals that satisfy mass conservation very well. Current research focuses on: a) optimising the performance of Savitzky-Golay filters, through selection of appropriate parameters (order of least

  17. Model development and verification for mass transport to Escherichia coli cells in a turbulent flow

    NASA Astrophysics Data System (ADS)

    Hondzo, Miki; Al-Homoud, Amer

    2007-08-01

    Theoretical studies imply that fluid motion does not significantly increase the molecular diffusive mass flux toward and away from microscopic organisms. This study presents experimental and theoretical evidence that small-scale turbulence modulates enhanced mass transport to Escherichia coli cells in a turbulent flow. Using the technique of inner region and outer region expansions, a model for dissolved oxygen and glucose uptake by E. coli was developed. The mass transport to the E. coli was modeled by the Sherwood (Sh)-Péclet (Pe) number relationship with redefined characteristic length and velocity scales. The model Sh = (1 + Pe1/2 + Pe) agreed with the laboratory measurements well. The Péclet number that quantifies the role and function of small-scale turbulence on E. coli metabolism is defined by Pe = (?) where Ezz is the root mean square of fluid extension in the direction of local vorticity, ηK is the Kolmogorov length scale, Lc is the length scale of E. coli, and D is the molecular diffusion coefficient. An alternative formulation for the redefined Pe is given by Pe = (?) where ? = 0.5(ɛν)1/4 is the Kolmogorov velocity averaged over the Kolmogorov length scale, ɛ is dissipation of turbulent kinetic energy, and ν is the kinematic viscosity of fluid. The dissipation of turbulent kinetic energy was estimated directly from measured velocity gradients and was within the reported range in engineered and natural aquatic ecosytems. The specific growth of E. coli was up to 5 times larger in a turbulent flow in comparison to the still water controls. Dissolved oxygen and glucose uptake were enhanced with increased ɛ in the turbulent flow.

  18. Transport Measurements on Individual Branched Nanostructures

    NASA Astrophysics Data System (ADS)

    Sun, Yong; Li, Wenzhi; Naughton, M. J.

    2005-03-01

    We have made electrical measurements on individual branched (``Y-junction") carbon nanotubes. After isolation on silicon substrates and identification via electron microscopy, photo and e-beam lithography were used to deposit metal electrodes (e.g. Au/Ti) onto individual branches of the nanostructures, including 4-probe configurations across a branch point (Y-junction). Various post-processing procedures, such as rapid thermal annealing and electron beam welding, were employed in attempts to improve contact resistances. Four-probe I-V measurements at room temperature yield varied intrinsic conductivity in these nanostructures (resistances between 10^4 and 10^7φ). Transmission microscopy reveals a fishbone internal structure, which could be responsible for the low conductance. We also report on the construction of ``divining rod'' cantilevers out of these branched nanotubes, using an etch-well technique, toward potential SPM applications, and on similar attempts using inorganic (e.g. ZnO2) nanowires.

  19. Precise measurements of the $W$ mass at the Tevatron and indirect constraints on the Higgs mass

    SciTech Connect

    Lopes de Sa, Rafael

    2012-04-01

    I describe the latest D0 and CDF W boson mass measurements. The D0 measurement is performed with 4.3 fb{sup -1} of integrated luminosity in the electron decay channel with a data set of 1.68 x 10{sup 8} W candidates. The value of the W boson mass measured by D0 is M{sub W} = 80.375 {+-} 0.023 GeV when combined with the previously analyzed 1 fb{sup -1} of integrated luminosity. The CDF measurement uses 2.2 fb{sup -1} of integrated luminosity in both electron and muon decay channels with a total of 1.1 x 10{sup 8} W candidates. The value of the W boson mass measured by CDF is M{sub W} = 80.387 {+-} 0.019 GeV. I report the combination of these two measurements with previous Tevatron measurements and with the LEP measurements of the W boson mass. The new world average is M{sub W} = 80.385 {+-} 0.015GeV. I discuss the implications of the new measurement to the indirect measurement of the Standard Model Higgs boson mass.

  20. A non-resonant mass sensor to eliminate the "missing mass" effect during mass measurement of biological materials

    NASA Astrophysics Data System (ADS)

    Shrikanth, V.; Bobji, M. S.

    2014-10-01

    Resonant sensors and crystal oscillators for mass detection need to be excited at very high natural frequencies (MHz). Use of such systems to measure mass of biological materials affects the accuracy of mass measurement due to their viscous and/or viscoelastic properties. The measurement limitation of such sensor system is the difficulty in accounting for the "missing mass" of the biological specimen in question. A sensor system has been developed in this work, to be operated in the stiffness controlled region at very low frequencies as compared to its fundamental natural frequency. The resulting reduction in the sensitivity due to non-resonant mode of operation of this sensor is compensated by the high resolution of the sensor. The mass of different aged drosophila melanogaster (fruit fly) is measured. The difference in its mass measurement during resonant mode of operation is also presented. That, viscosity effects do not affect the working of this non-resonant mass sensor is clearly established by direct comparison.

  1. A top quark mass measurement using a matrix element method

    SciTech Connect

    Linacre, Jacob Thomas

    2009-01-01

    A measurement of the mass of the top quark is presented, using top-antitop pair (t$\\bar{t}$) candidate events for the lepton+jets decay channel. The measurement makes use of Tevatron p$\\bar{p}$ collision data at centre-of-mass energy √s = 1.96 TeV, collected at the CDF detector. The top quark mass is measured by employing an unbinned maximum likelihood method where the event probability density functions are calculated using signal (t$\\bar{t}$) and background (W+jets) matrix elements, as well as a set of parameterised jet-to-parton mapping functions. The likelihood function is maximised with respect to the top quark mass, the fraction of signal events, and a correction to the jet energy scale (JES) of the calorimeter jets. The simultaneous measurement of the JES correction (ΔJES) provides an in situ jet energy calibration based on the known mass of the hadronically decaying W boson. Using 578 lepton+jets candidate events corresponding to 3.2 fb -1 of integrated luminosity, the top quark mass is measured to be mt = 172.4± 1.4 (stat+ΔJES) ±1.3 (syst) GeV=c2, one of the most precise single measurements to date.

  2. New technology directly measures mass flow of gas

    SciTech Connect

    Hahn, D.T.

    1995-12-31

    According to recent industry surveys and solicitations by organizations such as the Gas Research Institute and Small Business Innovation Research, a need exists for a gas flowmeter with {plus_minus}0.5% or better accuracy, that does not need to be calibrated for specific gas properties, and requires no periodic maintenance. Over the past 18 years, Coriolis mass flowmeters have provided these features for liquid flow applications, and have won a significant share of the liquid flow measurement market. Coriolis meters continue to be the fastest growing technology in the world market for flow measurement. Coriolis mass flowmeters have not, however, had much success in penetrating the gas flow measurement market due to some limitations involved with measuring the low density fluids associated with low pressure gas flow measurement. A new type of Coriolis mass flowmeter has been developed which utilizes a unique new method of creating and measuring the requisite Coriolis forces. This new technology; radial mode Coriolis mass flow measurement, has several inherent features that make it perfectly suited to measuring the mass flow of gas.

  3. Measurement of the mass difference between t and t quarks.

    PubMed

    Aaltonen, T; Álvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Appel, J A; Apresyan, A; Arisawa, T; Artikov, A; Asaadi, J; Ashmanskas, W; Auerbach, B; Aurisano, A; Azfar, F; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartos, P; Bauce, M; Bauer, G; Bedeschi, F; Beecher, D; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Bland, K R; Blumenfeld, B; Bocci, A; Bodek, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Brisuda, A; Bromberg, C; Brucken, E; Bucciantonio, M; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Calancha, C; Camarda, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Chung, W H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A; Compostella, G; Convery, M E; Conway, J; Corbo, M; Cordelli, M; Cox, C A; Cox, D J; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Dagenhart, D; d'Ascenzo, N; Datta, M; de Barbaro, P; De Cecco, S; De Lorenzo, G; Dell'Orso, M; Deluca, C; Demortier, L; Deng, J; Deninno, M; Devoto, F; d'Errico, M; Di Canto, A; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Dorigo, M; Dorigo, T; Ebina, K; Elagin, A; Eppig, A; Erbacher, R; Errede, D; Errede, S; Ershaidat, N; Eusebi, R; Fang, H C; Farrington, S; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Frank, M J; Franklin, M; Freeman, J C; Funakoshi, Y; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garfinkel, A F; Garosi, P; Gerberich, H; Gerchtein, E; Giagu, S; Giakoumopoulou, V; Giannetti, P; Gibson, K; Ginsburg, C M; Giokaris, N; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldin, D; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Group, R C; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, S R; Halkiadakis, E; Hamaguchi, A; Han, J Y; Happacher, F; Hara, K; Hare, D; Hare, M; Harr, R F; Hatakeyama, K; Hays, C; Heck, M; Heinrich, J; Herndon, M; Hewamanage, S; Hidas, D; Hocker, A; Hopkins, W; Horn, D; Hou, S; Hughes, R E; Hurwitz, M; Husemann, U; Hussain, N; Hussein, M; Huston, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jha, M K; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Ketchum, W; Keung, J; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, H W; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirby, M; Klimenko, S; Kondo, K; Kong, D J; Konigsberg, J; Kotwal, A V; Kreps, M; Kroll, J; Krop, D; Krumnack, N; Kruse, M; Krutelyov, V; Kuhr, T; Kurata, M; Kwang, S; Laasanen, A T; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, E; Lee, H S; Lee, J S; Lee, S W; Leo, S; Leone, S; Lewis, J D; Lin, C-J; Linacre, J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, C; Liu, Q; Liu, T; Lockwitz, S; Lockyer, N S; Loginov, A; Lucchesi, D; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lys, J; Lysak, R; Madrak, R; Maeshima, K; Makhoul, K; Maksimovic, P; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, C; Martínez, M; Martínez-Ballarín, R; Mastrandrea, P; Mathis, M; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzione, A; Mesropian, C; Miao, T; Mietlicki, D; Mitra, A; Miyake, H; Moed, S; Moggi, N; Mondragon, M N; Moon, C S; Moore, R; Morello, M J; Morlock, J; Movilla Fernandez, P; Mukherjee, A; Muller, Th; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Naganoma, J; Nakano, I; Napier, A; Nett, J; Neu, C; Neubauer, M S; Nielsen, J; Nodulman, L; Norniella, O; Nurse, E; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Ortolan, L; Pagan Griso, S; Pagliarone, C; Palencia, E; Papadimitriou, V; Paramonov, A A; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Pianori, E; Pilot, J; Pitts, K; Plager, C; Pondrom, L; Potamianos, K; Poukhov, O; Prokoshin, F; Pronko, A; Ptohos, F; Pueschel, E; Punzi, G; Pursley, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Renton, P; Rescigno, M; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rodriguez, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rubbo, F; Ruffini, F; Ruiz, A; Russ, J; Rusu, V; Safonov, A; Sakumoto, W K; Sakurai, Y; Santi, L; Sartori, L; Sato, K; Saveliev, V; Savoy-Navarro, A; Schlabach, P; Schmidt, A; Schmidt, E E; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sforza, F; Sfyrla, A; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shiraishi, S; Shochet, M; Shreyber, I; Simonenko, A; Sinervo, P; Sissakian, A; Sliwa, K; Smith, J R; Snider, F D; Soha, A; Somalwar, S; Sorin, V; Squillacioti, P; Stancari, M; Stanitzki, M; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Strycker, G L; Sudo, Y; Sukhanov, A; Suslov, I; Takemasa, K; Takeuchi, Y; Tang, J; Tecchio, M; Teng, P K; Thom, J; Thome, J; Thompson, G A; Thomson, E; Ttito-Guzmán, P; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Trovato, M; Tu, Y; Ukegawa, F; Uozumi, S; Varganov, A; Vázquez, F; Velev, G; Vellidis, C; Vidal, M; Vila, I; Vilar, R; Vizán, J; Vogel, M; Volpi, G; Wagner, P; Wagner, R L; Wakisaka, T; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Wilbur, S; Wick, F; Williams, H H; Wilson, J S; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, H; Wright, T; Wu, X; Wu, Z; Yamamoto, K; Yamaoka, J; Yang, T; Yang, U K; Yang, Y C; Yao, W-M; Yeh, G P; Yi, K; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanetti, A; Zeng, Y; Zucchelli, S

    2011-04-15

    We present a direct measurement of the mass difference between t and t quarks using tt candidate events in the lepton+jets channel, collected with the CDF II detector at Fermilab's 1.96 TeV Tevatron pp Collider. We make an event by event estimate of the mass difference to construct templates for top quark pair signal events and background events. The resulting mass difference distribution of data is compared to templates of signals and background using a maximum likelihood fit. From a sample corresponding to an integrated luminosity of 5.6  fb(-1), we measure a mass difference, ΔM(top) = M(t) - M(t) = -3.3 ± 1.4(stat) ± 1.0(syst)  GeV/c2, approximately 2 standard deviations away from the CPT hypothesis of zero mass difference.

  4. Precision measurement of a particle mass at the linear collider

    SciTech Connect

    Milstene, C.; Freitas, A.; Schmitt, M.; Sopczak, A.; /Lancaster U.

    2007-06-01

    Precision measurement of the stop mass at the ILC is done in a method based on cross-sections measurements at two different center-of-mass energies. This allows to minimize both the statistical and systematic errors. In the framework of the MSSM, a light stop, compatible with electro-weak baryogenesis, is studied in its decay into a charm jet and neutralino, the Lightest Supersymmetric Particle (LSP), as a candidate of dark matter. This takes place for a small stop-neutralino mass difference.

  5. Mass transfer and transport of radionuclides in fractured porous rock

    SciTech Connect

    Ahn, Joonhong

    1988-04-01

    Analytical studies are made to predict space-time dependent concentrations of radionuclides transported through water-saturated fractured porous rock. A basic model, which is expected to generate conservative results when used in long-term safety assessment of geologic repositories for radioactive waste, is established. Applicability and limitations of the model are investigated. 67 refs., 54 figs., 3 tabs.

  6. Finding the density of objects without measuring mass and volume

    NASA Astrophysics Data System (ADS)

    Mumba, Frackson; Tsige, Mesfin

    2007-05-01

    A simple method based on the moment of forces and Archimedes' principle is described for finding density without measuring the mass and volume of an object. The method involves balancing two unknown objects of masses M1 and M2 on each side of a pivot on a metre rule and measuring their corresponding moment arms. The object whose density is to be found is then immersed in a liquid of known density and the new moment of the arm of this object is measured. The density of the immersed object is then determined using only its measured moment arms and the density of the liquid.

  7. Mass transport in salt repositories: Steady-state transport through interbeds

    SciTech Connect

    Hwang, Y.; Lee, W.W.-L.; Chambre, P.L.; Pigford, T.H. . Dept. of Nuclear Engineering)

    1989-03-01

    Salt has long been a candidate for geologic disposal of nuclear waste. Because salt is extremely soluble in water, the existence of rock salt in the ground atest to the long-term stability of the salt. Both bedded salt and salt domes have been considered for nuclear waste disposal in the United States and Europe. While the salt is known to be quite pure in salt domes, bedded salt is interlaced with beds of sediments. Traditionally rock salt has not been considered water-conducting, but sediments layers would be classical porous media, capable of conducting water. Therefore there is interest in determining whether interbeds in bedded salt constitute pathway for radionuclide migration. In this report we consider steady-state migration of radionuclides from a single waste cylinder into a single interbed. Two approaches are used. In 1982 Neretnieks proposed an approach for calculating the steady-state transport of oxidants to a copper container. We have adapted that approach for calculating steady-state radionuclide migration away from the waste package, as a first approximation. We have also analyzed the problem of time-dependent radionuclide diffusion from a container through a backfill layer into a fracture, and we used the steady-state solution from that problem for comparison. Section 2 gives a brief summary of the geology of interbeds in bedded salt. Section 3 presents the mass transfer resistances approach of Neretnieks, summarizing the formulation and giving numerical illustrations of the steady-state two-dimensional diffusion analysis. Section 4 gives a brief statement of the steady-state result from a related analysis. Conclusions are stated in Section 5. 13 refs., 5 figs., 2 tabs.

  8. Discovery and Mass Measurements of a Cold, 10-Earth Mass Planet and Its Host Star

    NASA Technical Reports Server (NTRS)

    Barry, Richard K.; Muraki, Y.; Han, C.; Bennett, D. P.; Gaudi, B. S.

    2011-01-01

    We present the discovery and mass measurement of the cold, low-mass planet MOA-2009-BLG-266Lb, made with the gravitational microlensing method. This planet has a mass of mp = 10.4 +/- M(Earth) and orbits a star of Mstar = 0.56 +/- 0.09 M(Sun) at a semi-major axis of a = 3.2 + 1.9/-0.5 AU, and an orbital period of 7.6 +7.7/-1.5 yrs. The planet and host star mass measurements are due to the measurement of the microlensing parallax effect. This measurement was primarily due to the orbital motion of the Earth, but the analysis also demonstrates the capability measure micro lensing parallax with the Deep Impact (or EPOXI) spacecraft in a Heliocentric orbit. The planet mass and orbital distance are similar to predictions for the critical core mass needed to accrete a substantial gaseous envelope, and thus may indicate that this planet is a failed gas giant. This and future microlensing detections will test planet formation theory predictions regarding the prevalence and masses of such planets

  9. Noninvasive quantitative measurement of colloid transport in mesoscale porous media using time lapse fluorescence imaging.

    PubMed

    Bridge, Jonathan W; Banwart, Steven A; Heathwaite, A Louise

    2006-10-01

    We demonstrate noninvasive quantitative imaging of colloid and solute transport at millimeter to decimeter (meso-) scale. Ultraviolet (UV) excited fluorescent solute and colloid tracers were independently measured simultaneously during co-advection through saturated quartz sand. Pulse-input experiments were conducted at constant flow rates and ionic strengths 10(-3), 10(-2) and 10(-1) M NaCl. Tracers were 1.9 microm carboxylate latex microspheres and disodium fluorescein. Spatial moments analysis was used to quantify relative changes in mass distribution of the colloid and solute tracers over time. The solute advected through the sand at a constant velocity proportional to flow rate and was described well by a conservative transport model (CXTFIT). In unfavorable deposition conditions increasing ionic strength produced significant reduction in colloid center of mass transport velocity over time. Velocity trends correlated with the increasing fraction of colloid mass retained along the flowpath. Attachment efficiencies (defined by colloid filtration theory) calculated from nondestructive retained mass data were 0.013 +/- 0.03, 0.09 +/- 0.02, and 0.22 +/- 0.05 at 10(-3), 10(-2), and 10(-1) M ionic strength, respectively, which compared well with previously published data from breakthrough curves and destructive sampling. Mesoscale imaging of colloid mass dynamics can quantify key deposition and transport parameters based on noninvasive, nondestructive, spatially high-resolution data.

  10. Measurement of Chern numbers through center-of-mass responses

    NASA Astrophysics Data System (ADS)

    Price, H. M.; Zilberberg, O.; Ozawa, T.; Carusotto, I.; Goldman, N.

    2016-06-01

    Probing the center-of-mass of an ultracold atomic cloud can be used to measure Chern numbers, the topological invariants underlying the quantum Hall effects. In this work, we show how such center-of-mass observables can have a much richer dependence on topological invariants than previously discussed. In fact, the response of the center of mass depends not only on the current density, typically measured in a solid-state system, but also on the particle density, which itself can be sensitive to the topology of the band structure. We apply a semiclassical approach, supported by numerical simulations, to highlight the key differences between center-of-mass responses and more standard conductivity measurements. We illustrate this by analyzing both the two- and four-dimensional quantum Hall effects. These results have important implications for experiments in engineered topological systems, such as ultracold gases and photonics.

  11. Opportunistic Mass Measurements at the Holifield Radioactive Ion Beam Facility

    SciTech Connect

    Hausladen, Paul; Beene, James R; Galindo-Uribarri, Alfredo {nmn}; Larochelle, Y; Liang, J Felix; Mueller, Paul Edward; Shapira, Dan; Stracener, Daniel W; Thomas, J. S.; Varner Jr, Robert L; Wollnik, Hermann

    2006-01-01

    A technique for measuring mass differences has been developed at the Holifield Radioactive Ion Beam Facility (HRIBF) that requires no specialized equipment. Mass differences are measured as position differences between known and unknown-mass isobars, dispersed at the image of the energy-analyzing magnet following the 25MV tandem post-accelerator, and identified by an energy-loss measurement. The technique has been demonstrated on neutron-rich 77 79Cu and 83 86Ge isotopes produced using the isotope separator online (ISOL) method with the 238U(p,fission) reaction, where a mass accuracy of 500 keV was achieved. These nuclides are well suited to the measurement technique, as they readily migrate out of the production target and to the ion source and comprise the most neutron-rich elements of the isobarically mixed beam. Because modest precision mass values can be obtained with only a few tens of counts of the nuclide of interest among orders of magnitude more of the isobaric neighbors closer to stability, the sensitivity of this technique makes it appropriate for initial mass measurements far from stability.

  12. Measurements of the τ mass and the mass difference of the τ+ and τ- at BABAR

    NASA Astrophysics Data System (ADS)

    Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Tico, J. Garra; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; Lynch, G.; Osipenkov, I. L.; Tackmann, K.; Tanabe, T.; Hawkes, C. M.; Soni, N.; Watson, A. T.; Koch, H.; Schroeder, T.; Asgeirsson, D. J.; Fulsom, B. G.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Barrett, M.; Khan, A.; Randle-Conde, A.; Blinov, V. E.; Bukin, A. D.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Bondioli, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Lund, P.; Mandelkern, M.; Martin, E. C.; Stoker, D. P.; Atmacan, H.; Gary, J. W.; Liu, F.; Long, O.; Vitug, G. M.; Yasin, Z.; Sharma, V.; Campagnari, C.; Hong, T. M.; Kovalskyi, D.; Mazur, M. A.; Richman, J. D.; Beck, T. W.; Eisner, A. M.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Martinez, A. J.; Schalk, T.; Schumm, B. A.; Seiden, A.; Wang, L.; Winstrom, L. O.; Cheng, C. H.; Doll, D. A.; Echenard, B.; Fang, F.; Hitlin, D. G.; Narsky, I.; Ongmongkolku, P.; Piatenko, T.; Porter, F. C.; Andreassen, R.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Hirschauer, J. F.; Nagel, M.; Nauenberg, U.; Smith, J. G.; Wagner, S. R.; Ayad, R.; Toki, W. H.; Wilson, R. J.; Feltresi, E.; Hauke, A.; Jasper, H.; Karbach, T. M.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Kobel, M. J.; Nogowski, R.; Schubert, K. R.; Schwierz, R.; Bernard, D.; Latour, E.; Verderi, M.; Clark, P. J.; Playfer, S.; Watson, J. E.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cecchi, A.; Cibinetto, G.; Fioravanti, E.; Franchini, P.; Luppi, E.; Munerato, M.; Negrini, M.; Petrella, A.; Piemontese, L.; Santoro, V.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Contri, R.; Guido, E.; Lo Vetere, M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Tosi, S.; Chaisanguanthum, K. S.; Morii, M.; Adametz, A.; Marks, J.; Schenk, S.; Uwer, U.; Bernlochner, F. U.; Klose, V.; Lacker, H. M.; Lueck, T.; Volk, A.; Bard, D. J.; Dauncey, P. D.; Tibbetts, M.; Behera, P. K.; Charles, M. J.; Mallik, U.; Cochran, J.; Crawley, H. B.; Dong, L.; Eyges, V.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gao, Y. Y.; Gritsan, A. V.; Guo, Z. J.; Arnaud, N.; Béquilleux, J.; D'Orazio, A.; Davier, M.; Derkach, D.; da Costa, J. Firmino; Grosdidier, G.; Le Diberder, F.; Lepeltier, V.; Lutz, A. M.; Malaescu, B.; Pruvot, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Bingham, I.; Burke, J. P.; Chavez, C. A.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Clarke, C. K.; di Lodovico, F.; Sacco, R.; Sigamani, M.; Cowan, G.; Paramesvaran, S.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Hafner, A.; Alwyn, K. E.; Bailey, D.; Barlow, R. J.; Jackson, G.; Lafferty, G. D.; West, T. J.; Yi, J. I.; Anderson, J.; Chen, C.; Jawahery, A.; Roberts, D. A.; Simi, G.; Tuggle, J. M.; Dallapiccola, C.; Salvati, E.; Cowan, R.; Dujmic, D.; Fisher, P. H.; Henderson, S. W.; Sciolla, G.; Spitznagel, M.; Yamamoto, R. K.; Zhao, M.; Patel, P. M.; Robertson, S. H.; Schram, M.; Biassoni, P.; Lazzaro, A.; Lombardo, V.; Palombo, F.; Stracka, S.; Cremaldi, L.; Godang, R.; Kroeger, R.; Sonnek, P.; Summers, D. J.; Zhao, H. W.; Simard, M.; Taras, P.; Nicholson, H.; de Nardo, G.; Lista, L.; Monorchio, D.; Onorato, G.; Sciacca, C.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; Losecco, J. M.; Wang, W. F.; Corwin, L. A.; Honscheid, K.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.; Sekula, S. J.; Wong, Q. K.; Blount, N. L.; Brau, J.; Frey, R.; Igonkina, O.; Kolb, J. A.; Lu, M.; Rahmat, R.; Sinev, N. B.; Strom, D.; Strube, J.; Torrence, E.; Castelli, G.; Gagliardi, N.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Voci, C.; Del Amo Sanchez, P.; Ben-Haim, E.; Bonneaud, G. R.; Briand, H.; Chauveau, J.; Hamon, O.; Leruste, Ph.; Marchiori, G.; Ocariz, J.; Perez, A.; Prendki, J.; Sitt, S.; Gladney, L.; Biasini, M.; Manoni, E.; Angelini, C.; Batignani, G.; Bettarini, S.; Calderini, G.; Carpinelli, M.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Morganti, M.; Neri, N.; Paoloni, E.; Rizzo, G.; Walsh, J. J.; Pegna, D. Lopes; Lu, C.; Olsen, J.; Smith, A. J. S.; Telnov, A. V.; Anulli, F.; Baracchini, E.; Cavoto, G.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Jackson, P. D.; Gioi, L. Li; Mazzoni, M. A.; Morganti, S.; Piredda, G.; Renga, F.; Voena, C.; Ebert, M.; Hartmann, T.; Schröder, H.; Waldi, R.; Adye, T.; Franek, B.; Olaiya, E. O.; Wilson, F. F.; Emery, S.; Esteve, L.; de Monchenault, G. Hamel; Kozanecki, W.; Vasseur, G.; Yèche, Ch.; Zito, M.; Allen, M. T.; Aston, D.; Bartoldus, R.; Benitez, J. F.; Cenci, R.; Coleman, J. P.; Convery, M. R.; Dingfelder, J. C.; Dorfan, J.; Dubois-Felsmann, G. P.; Dunwoodie, W.; Field, R. C.; Sevilla, M. Franco; Gabareen, A. M.; Graham, M. T.; Grenier, P.; Hast, C.; Innes, W. R.; Kaminski, J.; Kelsey, M. H.; Kim, H.; Kim, P.; Kocian, M. L.; Leith, D. W. G. S.; Li, S.; Lindquist, B.; Luitz, S.; Luth, V.; Lynch, H. L.; Macfarlane, D. B.; Marsiske, H.; Messner, R.; Muller, D. R.; Neal, H.; Nelson, S.; O'Grady, C. P.; Ofte, I.; Perl, M.; Ratcliff, B. N.; Roodman, A.; Salnikov, A. A.; Schindler, R. H.; Schwiening, J.; Snyder, A.; Su, D.; Sullivan, M. K.; Suzuki, K.; Swain, S. K.; Thompson, J. M.; Va'Vra, J.; Wagner, A. P.; Weaver, M.; West, C. A.; Wisniewski, W. J.; Wittgen, M.; Wright, D. H.; Wulsin, H. W.; Yarritu, A. K.; Young, C. C.; Ziegler, V.; Chen, X. R.; Liu, H.; Park, W.; Purohit, M. V.; White, R. M.; Wilson, J. R.; Bellis, M.; Burchat, P. R.; Edwards, A. J.; Miyashita, T. S.; Ahmed, S.; Alam, M. S.; Ernst, J. A.; Pan, B.; Saeed, M. A.; Zain, S. B.; Soffer, A.; Spanier, S. M.; Wogsland, B. J.; Eckmann, R.; Ritchie, J. L.; Ruland, A. M.; Schilling, C. J.; Schwitters, R. F.; Wray, B. C.; Drummond, B. W.; Izen, J. M.; Lou, X. C.; Bianchi, F.; Gamba, D.; Pelliccioni, M.; Bomben, M.; Bosisio, L.; Cartaro, C.; Della Ricca, G.; Lanceri, L.; Vitale, L.; Azzolini, V.; Lopez-March, N.; Martinez-Vidal, F.; Milanes, D. A.; Oyanguren, A.; Albert, J.; Banerjee, Sw.; Bhuyan, B.; Choi, H. H. F.; Hamano, K.; King, G. J.; Kowalewski, R.; Lewczuk, M. J.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Gershon, T. J.; Harrison, P. F.; Ilic, J.; Latham, T. E.; Mohanty, G. B.; Puccio, E. M. T.; Band, H. R.; Chen, X.; Dasu, S.; Flood, K. T.; Pan, Y.; Prepost, R.; Vuosalo, C. O.; Wu, S. L.

    2009-11-01

    We present the result from a precision measurement of the mass of the τ lepton, Mτ, based on 423fb-1 of data recorded at the Υ(4S) resonance with the BABAR detector. Using a pseudomass endpoint method, we determine the mass to be 1776.68±0.12(stat)±0.41(syst)MeV. We also measure the mass difference between the τ+ and τ-, and obtain (Mτ+-Mτ-)/MAVGτ=(-3.4±1.3(stat)±0.3(syst))×10-4, where MAVGτ is the average value of Mτ+ and Mτ-.

  13. MEASURING THE MASS OF SOLAR SYSTEM PLANETS USING PULSAR TIMING

    SciTech Connect

    Champion, D. J.; Hobbs, G. B.; Manchester, R. N.; Edwards, R. T.; Burke-Spolaor, S.; Sarkissian, J. M.; Backer, D. C.; Bailes, M.; Bhat, N. D. R.; Van Straten, W.; Coles, W.; Demorest, P. B.; Ferdman, R. D.; Purver, M. B.; Folkner, W. M.; Hotan, A. W.; Kramer, M.; Lommen, A. N.; Nice, D. J.; Stairs, I. H.

    2010-09-10

    High-precision pulsar timing relies on a solar system ephemeris in order to convert times of arrival (TOAs) of pulses measured at an observatory to the solar system barycenter. Any error in the conversion to the barycentric TOAs leads to a systematic variation in the observed timing residuals; specifically, an incorrect planetary mass leads to a predominantly sinusoidal variation having a period and phase associated with the planet's orbital motion about the Sun. By using an array of pulsars (PSRs J0437-4715, J1744-1134, J1857+0943, J1909-3744), the masses of the planetary systems from Mercury to Saturn have been determined. These masses are consistent with the best-known masses determined by spacecraft observations, with the mass of the Jovian system, 9.547921(2) x10{sup -4} M {sub sun}, being significantly more accurate than the mass determined from the Pioneer and Voyager spacecraft, and consistent with but less accurate than the value from the Galileo spacecraft. While spacecraft are likely to produce the most accurate measurements for individual solar system bodies, the pulsar technique is sensitive to planetary system masses and has the potential to provide the most accurate values of these masses for some planets.

  14. Direct mass measurements of the heaviest elements with Penning traps

    NASA Astrophysics Data System (ADS)

    Block, M.

    2015-12-01

    Penning-trap mass spectrometry (PTMS) is a mature technique to provide atomic masses with highest precision. Applied to radionuclides it enables us to investigate their nuclear structure via binding energies and derived quantities such as nucleon separation energies. Recent progress in slowing down radioactive ion beams in buffer gas cells in combination with advanced ion-manipulation techniques has opened the door to access even the elements above fermium by PTMS. Such elements are produced in complete fusion-evaporation reactions of heavy ions with lead, bismuth, and actinide targets at very low rates. Pioneering high-precision mass measurements of nobelium and lawrencium isotopes have been performed with SHIPTRAP at the GSI Darmstadt, Germany. These have illustrated that direct mass measurements provide reliable anchor points to pin down decay chains and that they allow mapping nuclear shell effects, the reason for the very existence of the heaviest elements. Thus, accurate masses contribute to our understanding of these exotic nuclei with extreme proton numbers. In this article experimental challenges in mass measurements of the heaviest elements with Penning traps are discussed. Some illustrative examples of the nuclear structure features displayed based on the presently known masses are given.

  15. Mass measurements of neutron-rich Rb and Sr isotopes

    NASA Astrophysics Data System (ADS)

    Klawitter, R.; Bader, A.; Brodeur, M.; Chowdhury, U.; Chaudhuri, A.; Fallis, J.; Gallant, A. T.; Grossheim, A.; Kwiatkowski, A. A.; Lascar, D.; Leach, K. G.; Lennarz, A.; Macdonald, T. D.; Pearkes, J.; Seeraji, S.; Simon, M. C.; Simon, V. V.; Schultz, B. E.; Dilling, J.

    2016-04-01

    We report on the mass measurements of several neutron-rich Rb and Sr isotopes in the A ≈100 region with the TITAN Penning-trap mass spectrometer. By using highly charged ions in the charge state q =10 + , the masses of Rb,9998 and Sr-10098 have been determined with a precision of 6-12 keV, making their uncertainty negligible for r -process nucleosynthesis network calculations. The mass of 101Sr has been determined directly for the first time with a precision eight times higher than the previous indirect measurement and a deviation of 3 σ when compared to the Atomic Mass Evaluation. We also confirm the mass of 100Rb from a previous measurement. Furthermore, our data indicate the existence of a low-lying isomer with 80 keV excitation energy in 98Rb. We show that our updated mass values lead to minor changes in the r process by calculating fractional abundances in the A ≈100 region of the nuclear chart.

  16. Molecular transport in collagenous tissues measured by gel electrophoresis.

    PubMed

    Hunckler, Michael D; Tilley, Jennifer M R; Roeder, Ryan K

    2015-11-26

    Molecular transport in tissues is important for drug delivery, nutrient supply, waste removal, cell signaling, and detecting tissue degeneration. Therefore, the objective of this study was to investigate gel electrophoresis as a simple method to measure molecular transport in collagenous tissues. The electrophoretic mobility of charged molecules in tissue samples was measured from relative differences in the velocity of a cationic dye passing through an agarose gel in the absence and presence of a tissue section embedded within the gel. Differences in electrophoretic mobility were measured for the transport of a molecule through different tissues and tissue anisotropy, or the transport of different sized molecules through the same tissue. Tissue samples included tendon and fibrocartilage from the proximal (tensile) and distal (compressive) regions of the bovine flexor tendon, respectively, and bovine articular cartilage. The measured electrophoretic mobility was greatest in the compressive region of the tendon (fibrocartilage), followed by the tensile region of tendon, and lowest in articular cartilage, reflecting differences in the composition and organization of the tissues. The anisotropy of tendon was measured by greater electrophoretic mobility parallel compared with perpendicular to the predominate collagen fiber orientation. Electrophoretic mobility also decreased with increased molecular size, as expected. Therefore, the results of this study suggest that gel electrophoresis may be a useful method to measure differences in molecular transport within various tissues, including the effects of tissue type, tissue anisotropy, and molecular size.

  17. Automated measurement of fast mitochondrial transport in neurons

    PubMed Central

    Miller, Kyle E.; Liu, Xin-An; Puthanveettil, Sathyanarayanan V.

    2015-01-01

    There is growing recognition that fast mitochondrial transport in neurons is disrupted in multiple neurological diseases and psychiatric disorders. However, a major constraint in identifying novel therapeutics based on mitochondrial transport is that the large-scale analysis of fast transport is time consuming. Here we describe methodologies for the automated analysis of fast mitochondrial transport from data acquired using a robotic microscope. We focused on addressing questions of measurement precision, speed, reliably, workflow ease, statistical processing, and presentation. We used optical flow and particle tracking algorithms, implemented in ImageJ, to measure mitochondrial movement in primary cultured cortical and hippocampal neurons. With it, we are able to generate complete descriptions of movement profiles in an automated fashion of hundreds of thousands of mitochondria with a processing time of approximately one hour. We describe the calibration of the parameters of the tracking algorithms and demonstrate that they are capable of measuring the fast transport of a single mitochondrion. We then show that the methods are capable of reliably measuring the inhibition of fast mitochondria transport induced by the disruption of microtubules with the drug nocodazole in both hippocampal and cortical neurons. This work lays the foundation for future large-scale screens designed to identify compounds that modulate mitochondrial motility. PMID:26578890

  18. A rain splash transport equation assimilating field and laboratory measurements

    NASA Astrophysics Data System (ADS)

    Dunne, Thomas; Malmon, Daniel V.; Mudd, Simon M.

    2010-03-01

    Process-based models of hillslope evolution require transport equations relating sediment flux to its major controls. An equation for rain splash transport in the absence of overland flow was constructed by modifying an approach developed by Reeve (1982) and parameterizing it with measurements from single-drop laboratory experiments and simulated rainfall on a grassland in East Africa. The equation relates rain splash to hillslope gradient, the median raindrop diameter of a storm, and ground cover density; the effect of soil texture on detachability can be incorporated from other published results. The spatial and temporal applicability of such an equation for rain splash transport in the absence of overland flow on uncultivated hillslopes can be estimated from hydrological calculations. The predicted transport is lower than landscape-averaged geologic erosion rates from Kenya but is large enough to modify short, slowly eroding natural hillslopes as well as microtopographic interrill surfaces between which overland flow transports the mobilized sediment.

  19. Body Mass Index Measurement in Schools. Executive Summary

    ERIC Educational Resources Information Center

    Centers for Disease Control and Prevention, 2007

    2007-01-01

    As the United States continues to search for answers to the growing problem of obesity among children and adolescents, much attention has focused on body mass index (BMI) measurement programs in schools. The BMI is the ratio of weight to height squared. It is often used to assess weight status because it is relatively easy to measure and it…

  20. Investigating Young Children's Learning of Mass Measurement

    ERIC Educational Resources Information Center

    Cheeseman, Jill; McDonough, Andrea; Ferguson, Sarah

    2014-01-01

    This paper reports results of a design experiment regarding young children's concepts of mass measurement. The research built on an earlier study in which a framework of "growth points" in early mathematics learning and a related, task-based, one-to-one interview to assess children's understanding of the measurement of mass…

  1. Mass Measurement System Using Relay Feedback with Hysteresis

    NASA Astrophysics Data System (ADS)

    Mizuno, Takeshi; Adachi, Takahiro; Takasaki, Masaya; Ishino, Yuji

    Mass measurement using a relay feedback system was studied experimentally. The measurement system has an on-off relay with hysteresis and switches force acting on the object in relation to its velocity. Such nonlinear control induces a limit cycle in the feedback system. The mass of the object is determined from the period of this limit cycle. The apparatus manufactured for experimental study uses two voice coil motors (VCM's), one of which is for driving the object and the other is for generating prescribed disturbances. The effects of system parameters and disturbances on measurement accuracy were examined experimentally.

  2. Top quark mass measurement at CDF Run-II

    SciTech Connect

    T. Maruyama

    2004-05-11

    CDF has resumed the top quark mass measurement with upgraded detectors and Tevatron complex. High statistics should allow us to determine the top mass with an uncertainty of a few GeV/c{sup 2} by the end of Run II. The current measured value, using an integrated luminosity of {approx} 108 pb{sup -1}, is 177.5{sub -9.4}{sup +12.7} (stat.) {+-} 7.1(syst.) GeV/c{sup 2} (lepton + jets with one b-jet tagged mode: the current best mode), which is consistent with RunI measurements.

  3. Economic evaluation of traffic safety measures for transport companies.

    PubMed

    Rienstra, S A; Rietveld, P; Lindeijer, J E

    2000-09-01

    This paper addresses the economic feasibility of measures to reduce the material damage of transport companies. Results are presented of a series of interviews among transport companies as well as from a postal questionnaire survey. Next, calculations are presented for three types of companies: a small family company, a large family company and a large formalised company. From the viewpoint of costs and benefits, damage prevention measures appear to be particularly interesting to larger companies. Small companies, being the largest group, tend to have an informal culture in which measures are less effective. Especially those measures for which no large investments are needed, which influence the behaviour of drivers and need not to be contracted out, are perceived as attractive by the transport companies.

  4. Mass measuring instrument for use under microgravity conditions

    SciTech Connect

    Fujii, Yusaku; Yokota, Masayuki; Hashimoto, Seiji; Sugita, Yoichi; Ito, Hitomi; Shimada, Kazuhito

    2008-05-15

    A prototype instrument for measuring astronaut body mass under microgravity conditions has been developed and its performance was evaluated by parabolic flight tests. The instrument, which is the space scale, is applied as follows. Connect the subject astronaut to the space scale with a rubber cord. Use a force transducer to measure the force acting on the subject and an optical interferometer to measure the velocity of the subject. The subject's mass is calculated as the impulse divided by the velocity change, i.e., M={integral}Fdt/{delta}v. Parabolic flight by using a jet aircraft produces a zero-gravity condition lasting approximately 20 s. The performance of the prototype space scale was evaluated during such a flight by measuring the mass of a sample object.

  5. Mass and heat transport in direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Ismail, A.; Kamarudin, S. K.; Daud, W. R. W.; Masdar, S.; Yosfiah, M. R.

    The direct methanol fuel cell (DMFC) is a better alternative to the conventional battery. The DMFC offers several advantages, namely, faster building of potential and longer-lasting fuel, however, there are still several issues that need to be addressed to design a better DMFC system. This article is a wide-ranging review of the most up-to-date studies on mass and heat transfer in the DMFC. The discussion will be focused on the critical problems limiting the performance of DMFCs. In addition, a technique for upgrading the DMFC with an integrated system will be presented, along with existing numerical models for modeling mass and heat transfer as well as cell performance.

  6. Mass

    SciTech Connect

    Quigg, Chris

    2007-12-05

    In the classical physics we inherited from Isaac Newton, mass does not arise, it simply is. The mass of a classical object is the sum of the masses of its parts. Albert Einstein showed that the mass of a body is a measure of its energy content, inviting us to consider the origins of mass. The protons we accelerate at Fermilab are prime examples of Einsteinian matter: nearly all of their mass arises from stored energy. Missing mass led to the discovery of the noble gases, and a new form of missing mass leads us to the notion of dark matter. Starting with a brief guided tour of the meanings of mass, the colloquium will explore the multiple origins of mass. We will see how far we have come toward understanding mass, and survey the issues that guide our research today.

  7. Synoptic patterns and air mass transport during ozone episodes in northwestern Iberia.

    PubMed

    Saavedra, S; Rodríguez, A; Taboada, J J; Souto, J A; Casares, J J

    2012-12-15

    High levels of ozone are frequently measured at the Galicia (NW Iberian Peninsula) air quality monitoring stations from March to October. However, there have been very few studies on surface ozone in the northwestern Iberian Peninsula, most likely because the climate of this region is not favourable to photochemical ozone generation. The occurrence of these episodes may be related to either local-scale photochemical pollution or regional-scale transport from other polluted regions. In addition, high ozone episodes usually are developed under specific synoptic conditions. The main purposes of this study are to characterise the atmospheric conditions that lead to the ozone episodes in this region and to identify possible advection paths of ozone and precursors. A surface hourly ozone dataset (2002-2007) measured at rural sites in Galicia was analysed to identify high ozone episodes together with their associated synoptic patterns using a subjective classification with 23 different synoptic types. The synoptic weather patterns revealed that most of the episodes occur with high surface pressures centred over the British Isles and/or Central Europe while a high-altitude anticyclonic ridge crosses the Peninsula from North Africa, causing easterly or southeasterly winds. This analysis was completed with 3-day backward air mass trajectories obtained with HYSPLIT to assess the contribution of long-range transport, resulting in the following main routes: Mediterranean-Peninsular, South Atlantic-Portuguese, local and French-Cantabric.

  8. A CLOSURE STUDY OF AEROSOL MASS CONCENTRATION MEASUREMENTS: COMPARISON OF VALUES OBTAINED WITH FILTERS AND BY DIRECT MEASUREMENTS OF MASS DISTRIBUTIONS. (R826372)

    EPA Science Inventory

    We compare measurements of aerosol mass concentrations obtained gravimetrically using Teflon coated glass fiber filters and by integrating mass distributions measured with the differential mobility analyzer–aerosol particle mass analyzer (DMA–APM) technique (Aero...

  9. Atomic mass measurements and nuclear spectroscopy at TRISTAN

    NASA Astrophysics Data System (ADS)

    Brenner, D. S.

    1981-02-01

    This research program is concerned with measuring atomic masses and decay schemes of short-lived, neutron-rich fission products with the TRISTAN on-line mass separator located at the High Flux Beam Reactor (HFBR), Brookhaven National Laboratory. The determination of accurate masses for neutron rich nuclei is useful in refining mass equations which, in turn, are important for calculations related to astrophysical processes and to control and to safety of nuclear reactors. During the period covered by this report, efforts were made to aid Brookhaven personnel in the installation and testing of TRISTAN and the associated computer systems, and to begin a program of measurements of beta-ray end-point energies and nuclear decay schemes following successful demonstration of the facility.

  10. Effect of isotope mass on transport simulations of Joint European Torus high-mode plasmas with Edge Localized Modes

    NASA Astrophysics Data System (ADS)

    Bateman, Glenn; Kritz, Arnold H.; Parail, Vassili V.; Cordey, J. G.

    1999-12-01

    The effect of isotopic mass on heat and particle transport in Joint European Torus (JET) [P.-H. Rebut et al., Nucl. Fusion 25, 1011 (1985)] plasma discharges is studied using the Multi-Mode model in the BALDUR predictive transport code [Bateman et al., Phys. Plasmas 5, 1793 (1998)]. Temperature and density profiles from these simulations generally agree with the experimentally measured profiles for high-mode JET discharges with Edge Localized Modes in hydrogen, deuterium, and tritium discharges. It is surprising that a purely gyro-Bohm transport model, used in these simulations, correctly predicts the experimentally observed improvement in confinement as the isotope mass is increased—given the fact that gyro-Bohm diffusion coefficients increase with isotope mass when the shapes of all the plasma profiles are held fixed. However, in the JET experiment, it was found that the electron and ion temperature at the top of the edge pedestal increases systematically as the isotope mass in increased (J. G. Cordey et al., Report No. JET-P (98)53, 1998). The numerical simulations reported here show that this increase in the edge temperatures and subsequent broadening of the temperature profiles account for the improvement in confinement as the isotope mass is increased.

  11. Measurement of collective dynamical mass of Dirac fermions in graphene.

    PubMed

    Yoon, Hosang; Forsythe, Carlos; Wang, Lei; Tombros, Nikolaos; Watanabe, Kenji; Taniguchi, Takashi; Hone, James; Kim, Philip; Ham, Donhee

    2014-08-01

    Individual electrons in graphene behave as massless quasiparticles. Unexpectedly, it is inferred from plasmonic investigations that electrons in graphene must exhibit a non-zero mass when collectively excited. The inertial acceleration of the electron collective mass is essential to explain the behaviour of plasmons in this material, and may be directly measured by accelerating it with a time-varying voltage and quantifying the phase delay of the resulting current. This voltage-current phase relation would manifest as a kinetic inductance, representing the reluctance of the collective mass to accelerate. However, at optical (infrared) frequencies, phase measurements of current are generally difficult, and, at microwave frequencies, the inertial phase delay has been buried under electron scattering. Therefore, to date, the collective mass in graphene has defied unequivocal measurement. Here, we directly and precisely measure the kinetic inductance, and therefore the collective mass, by combining device engineering that reduces electron scattering and sensitive microwave phase measurements. Specifically, the encapsulation of graphene between hexagonal boron nitride layers, one-dimensional edge contacts and a proximate top gate configured as microwave ground together enable the inertial phase delay to be resolved from the electron scattering. Beside its fundamental importance, the kinetic inductance is found to be orders of magnitude larger than the magnetic inductance, which may be utilized to miniaturize radiofrequency integrated circuits. Moreover, its bias dependency heralds a solid-state voltage-controlled inductor to complement the prevalent voltage-controlled capacitor.

  12. Mass transport, corrosion, plugging, and their reduction in solar dish/Stirling heat pipe receivers

    SciTech Connect

    Adkins, D.R.; Andraka, C.E.; Bradshaw, R.W.; Goods, S.H.; Moreno, J.B.; Moss, T.A.

    1996-07-01

    Solar dish/Stirling systems using sodium heat pipe receivers are being developed by industry and government laboratories here and abroad. The unique demands of this application lead to heat pipe wicks with very large surface areas and complex three-dimensional flow patterns. These characteristics can enhance the mass transport and concentration of constituents of the wick material, resulting in wick corrosion and plugging. As the test times for heat pipe receivers lengthen, we are beginning to see these effects both indirectly, as they affect performance, and directly in post-test examinations. We are also beginning to develop corrective measures. In this paper, we report on our test experiences, our post-test examinations, and on our initial effort to ameliorate various problems.

  13. On the optimum fields and bounds for heat and mass transport in two turbulent flows

    NASA Astrophysics Data System (ADS)

    Vitanov, Nikolay

    2011-12-01

    The optimum theory of turbulence is one of the few tools for obtaining analytical results for transport of heat, mass or momentum by turbulent flows. This is achieved by asymptotic theory which is valid for large values of the characteristic numbers of the investigated fluid system. For small and intermediate values of the Reynolds, Rayleigh or Taylor numbers we have to solve numerically the Euler-Lagrange equations of the corresponding variational problems. Below we discuss numerical results from the application of the Howard-Busse method of the optimum theory of turbulence to two problems: convective heat transport in non-rotating and rotating fluid layer and mass transport in pipe flow. We obtain profiles of the optimum fields and discuss the evolution of the thickness of the boundary layers as well as present our first results about the lower bound on the mass transport in a pipe flow.

  14. New mass transport elements and components for the NIST IAQ Model

    SciTech Connect

    Axley, J.W.

    1995-07-01

    This report presents new mass transport elements for the next generation of the NIST IAQ Model that may be used to model (1) homogenous (bulk-air) chemistry within well-mixed chamber, (2) aerosol mass transport within well-mixed chambers and fractional particle filtration in building filtration devices, and (3) heterogeneous (surface-related) physical processes and chemical transformations including those governing the behavior of gas-phase air cleaning devices. In an effort to maintain rigor, generality, and flexibility, each transport process is formulated in terms of the elemental mass transport step that together govern the overall process. In this way, the more complex processes may be represented as component equations that are assembled from fundamental element equations.

  15. Measuring the Mass Ratio of the Deuteron to the Proton

    NASA Astrophysics Data System (ADS)

    Langley, Thomas; Nicholas, Rebecca

    1998-03-01

    An experiment was conducted to measure the ratio of the mass of the deuterium nucleus to the mass of the proton. This was done using a monochromator to record the spectral lines emitted from a deuterium source containing some residual hydrogen. The spectral lines of this source were detected by a photomultiplier and recorded by a computer. The software program LabView was used to graph and record data so that the isotropic shift in the alpha emission could be extracted.

  16. Transport of magnetic flux and mass in Saturn's inner magnetosphere

    NASA Astrophysics Data System (ADS)

    Lai, H. R.; Russell, C. T.; Jia, Y. D.; Wei, H. Y.; Dougherty, M. K.

    2016-04-01

    It is well accepted that cold plasma sourced by Enceladus is ultimately lost to the solar wind, while the magnetic flux convecting outward with the plasma must return to the inner magnetosphere. However, whether the interchange or reconnection, or a combination of the two processes is the dominant mechanism in returning the magnetic flux is still under debate. Initial Cassini observations have shown that the magnetic flux returns in the form of flux tubes in the inner magnetosphere. Here we investigate those events with 10 year Cassini magnetometer data and confirm that their magnetic signatures are determined by the background plasma environments: inside (outside) the plasma disk, the returning magnetic field is enhanced (depressed) in strength. The distribution, temporal variation, shape, and transportation rate of the flux tubes are also characterized. The flux tubes break into smaller ones as they convect in. The shape of their cross section is closer to circular than fingerlike as produced in the simulations based on the interchange mechanism. In addition, no sudden changes in any flux tube properties can be found at the "boundary" which has been claimed to separate the reconnection and interchange-dominant regions. On the other hand, reasonable cold plasma loss rate and outflow velocity can be obtained if the transport rate of the magnetic flux matches the reconnection rate, which supports reconnection alone as the dominant mechanism in unloading the cold plasma from the inner magnetosphere and returning the magnetic flux from the tail.

  17. Dynamical Mass Measurements of Contaminated Galaxy Clusters Using Machine Learning

    NASA Astrophysics Data System (ADS)

    Ntampaka, Michelle; Trac, Hy; Sutherland, Dougal; Fromenteau, Sebastien; Poczos, Barnabas; Schneider, Jeff

    2016-01-01

    Galaxy clusters are a rich source of information for examining fundamental astrophysical processes and cosmological parameters, however, employing clusters as cosmological probes requires accurate mass measurements derived from cluster observables. We study dynamical mass measurements of galaxy clusters contaminated by interlopers, and show that a modern machine learning (ML) algorithm can predict masses by better than a factor of two compared to a standard scaling relation approach. We create a mock catalog from Multidark's publicly-available N-body MDPL1 simulation where a simple cylindrical cut around the cluster center allows interlopers to contaminate the clusters. In the standard approach, we use a power law scaling relation to infer cluster mass from galaxy line of sight (LOS) velocity dispersion. The presence of interlopers in the catalog produces a wide, flat fractional mass error distribution, with width = 2.13. We employ the Support Distribution Machine (SDM) class of algorithms to learn from distributions of data to predict single values. Applied to distributions of galaxy observables such as LOS velocity and projected distance from the cluster center, SDM yields better than a factor-of-two improvement (width = 0.67). Remarkably, SDM applied to contaminated clusters is better able to recover masses than even a scaling relation approach applied to uncontaminated clusters. We show that the SDM method more accurately reproduces the cluster mass function, making it a valuable tool for employing cluster observations to evaluate cosmological models.

  18. Nonergodicity and localization of invariant measure for two colliding masses

    NASA Astrophysics Data System (ADS)

    Wang, Jiao; Casati, Giulio; Prosen, Tomaž

    2014-04-01

    We show evidence, based on extensive and carefully performed numerical experiments, that the system of two elastic hard-point masses in one dimension is not ergodic for a generic mass ratio and consequently does not follow the principle of energy equipartition. This system is equivalent to a right triangular billiard. Remarkably, following the time-dependent probability distribution in a suitably chosen velocity direction space, we find evidence of exponential localization of invariant measure. For nongeneric mass ratios which correspond to billiard angles which are rational, or weak irrational multiples of π, the system is ergodic, consistent with existing rigorous results.

  19. A Comprehensive Flow, Heat and Mass Transport Uncertainty Quantification in Discrete Fracture Network Systems

    NASA Astrophysics Data System (ADS)

    Ezzedine, S. M.

    2010-12-01

    Fractures and fracture networks are the principle pathways for migration of water, heat and mass in enhanced geothermal systems, oil and gas reservoirs, CO2 leakage from saline aquifers, and radioactive and toxic industrial wastes from underground storage repositories. A major issue to overcome when characterizing a fractured reservoir is that of data limitation due to accessibility and affordability. Moreover, the ability to map discontinuities in the rock with available geological and geophysical tools tends to decrease particularly as the scale of the discontinuity goes down. Geological characterization data include measurements of fracture density, orientation, extent, and aperture, and are based on analysis of outcrops, borehole optical and acoustic televiewer logs, aerial photographs, and core samples among others. All of these measurements are taken at the field scale through a very sparse limited number of deep boreholes. These types of data are often reduced to probability distributions function for predictive modeling and simulation in a stochastic framework such as stochastic discrete fracture network. Stochastic discrete fracture network models enable, through Monte Carlo realizations and simulations, for probabilistic assessment of flow and transport phenomena that are not adequately captured using continuum models. Despite the fundamental uncertainties inherited within the probabilistic reduction of the sparse data collected, very little work has been conducted on quantifying uncertainty on the reduced probabilistic distribution functions. In the current study, using nested Monte Carlo simulations, we present the impact of parameter uncertainties of the distribution functions that characterize discrete fracture networks on the flow, heat and mass transport. Numerical results of first, second and third moments, normalized to a base case scenario, are presented and compared to theoretical results extended from percolation theory.

  20. Top quark mass measurement using the template method at CDF

    DOE PAGES

    Aaltonen, T

    2011-06-03

    We present a measurement of the top quark mass in the lepton+jets and dilepton channels of tmore » $$\\bar{t}$$ decays using the template method. The data sample corresponds to an integrated luminosity of 5.6 fb-1 of p$$\\bar{p}$$ collisions at Tevatron with √s = 1.96 TeV, collected with the CDF II detector. The measurement is performed by constructing templates of three kinematic variables in the lepton+jets and two kinematic variables in the dilepton channel. The variables are two reconstructed top quark masses from different jets-to-quarks combinations and the invariant mass of two jets from the W decay in the lepton+jets channel, and a reconstructed top quark mass and mT2, a variable related to the transverse mass in events with two missing particles, in the dilepton channel. The simultaneous fit of the templates from signal and background events in the lepton+jets and dilepton channels to the data yields a measured top quark mass of Mtop = 172.1±1.1 (stat)±0.9 (syst) GeV/c2.« less

  1. Top quark mass measurement using the template method at CDF

    SciTech Connect

    Aaltonen, T

    2011-06-03

    We present a measurement of the top quark mass in the lepton+jets and dilepton channels of t$\\bar{t}$ decays using the template method. The data sample corresponds to an integrated luminosity of 5.6 fb-1 of p$\\bar{p}$ collisions at Tevatron with √s = 1.96 TeV, collected with the CDF II detector. The measurement is performed by constructing templates of three kinematic variables in the lepton+jets and two kinematic variables in the dilepton channel. The variables are two reconstructed top quark masses from different jets-to-quarks combinations and the invariant mass of two jets from the W decay in the lepton+jets channel, and a reconstructed top quark mass and mT2, a variable related to the transverse mass in events with two missing particles, in the dilepton channel. The simultaneous fit of the templates from signal and background events in the lepton+jets and dilepton channels to the data yields a measured top quark mass of Mtop = 172.1±1.1 (stat)±0.9 (syst) GeV/c2.

  2. Coupled effects of temperature and mass transport on the isotope fractionation of zinc during electroplating

    NASA Astrophysics Data System (ADS)

    Black, Jay R.; John, Seth G.; Kavner, Abby

    2014-01-01

    The isotopic composition of zinc metal electrodeposited on a rotating disc electrode from a Zn-citrate aqueous solution was investigated as a function of overpotential (electrochemical driving force), temperature, and rotation rate. Zn metal was measured to be isotopically light with respect to Zn+2 in solution, with observed fractionations varying from Δ66/64Znmetal-aqueous = -1.0‰ to -3.9‰. Fractionation varies continuously as a function of a dimensionless parameter described by the ratio of observed deposition rate to calculated mass-transport limiting rate, where larger fractionations are observed at lower deposition rates, lower temperature, and at faster electrode rotation rates. Thus, the large fractionation and its rate dependence is interpreted as a competition between the two kinetic processes with different effective activation energies: mass-transport-limited (diffusion limited) kinetics with a large activation energy, which creates small fractionations close to the predicted diffusive fractionation; and electrochemical deposition kinetics, with a smaller effective activation energy, which creates large fractionations at low deposition rates and high hydrodynamic fluxes of solute to the electrode. The results provide a framework for predicting isotope fractionation in processes controlled by two competing reactions with different kinetic isotope effects. Light isotopes are electroplated. In all cases light stable isotopes of the metals are preferentially electroplated, with mass-dependent behavior evident where three or more isotopes are measured. Fractionation is time-independent, meaning that the fractionation factor does not vary with the extent of reaction. In most of our experiments, we have controlled the extent of reaction such that only a small amount of metal is deposited from the stock solution, thus avoiding significant evolution of the reservoir composition. In such experiments, the observed isotope fractionation is constant as a

  3. Measurements of the top quark mass at the Tevatron

    SciTech Connect

    Brandt, Oleg; /Gottingen U., II. Phys. Inst.

    2012-04-01

    The mass of the top quark (m{sub top}) is a fundamental parameter of the standard model (SM). Currently, its most precise measurements are performed by the CDF and D0 collaborations at the Fermilab Tevatron p{bar p} collider at a centre-of-mass energy of {radical}s = 1.96 TeV. We review the most recent of those measurements, performed on data samples of up to 8.7 fb{sup -1} of integrated luminosity. The Tevatron combination using up to 5.8 fb{sup -1} of data results in a preliminary world average top quark mass of m{sub top} = 173.2 {+-} 0.9 GeV. This corresponds to a relative precision of about 0.54%. We conclude with an outlook of anticipated precision the final measurement of m{sub top} at the Tevatron.

  4. The Mass Accretion Rate of Galaxy Clusters: A Measurable Quantity

    NASA Astrophysics Data System (ADS)

    De Boni, C.; Serra, A. L.; Diaferio, A.; Giocoli, C.; Baldi, M.

    2016-02-01

    We explore the possibility of measuring the mass accretion rate (MAR) of galaxy clusters from their mass profiles beyond the virial radius R200. We derive the accretion rate from the mass of a spherical shell whose inner radius is 2R200, whose thickness changes with redshift, and whose infall velocity is assumed to be equal to the mean infall velocity of the spherical shells of dark matter halos extracted from N-body simulations. This approximation is rather crude in hierarchical clustering scenarios where both smooth accretion and aggregation of smaller dark matter halos contribute to the mass accretion of clusters. Nevertheless, in the redshift range z = [0, 2], our prescription returns an average MAR within 20%-40% of the average rate derived from the merger trees of dark matter halos extracted from N-body simulations. The MAR of galaxy clusters has been the topic of numerous detailed numerical and theoretical investigations, but so far it has remained inaccessible to measurements in the real universe. Since the measurement of the mass profile of clusters beyond their virial radius can be performed with the caustic technique applied to dense redshift surveys of the cluster outer regions, our result suggests that measuring the mean MAR of a sample of galaxy clusters is actually feasible. We thus provide a new potential observational test of the cosmological and structure formation models.

  5. Rare-RI ring for mass measurements at RIBF

    SciTech Connect

    Ozawa, Akira

    2014-05-02

    The rare-RI (radioactive isotope) ring at the RIKEN RI Beam Factory is described. The main purpose of the rare-RI ring is to measure the mass of short-lived rare RI. In the rare-RI ring, the mass is determined by measuring the revolution time of each nucleus based on isochronous mass spectrometry. The rare-RI ring consists of six magnetic sectors, and each sector consists of four dipole magnets. To precisely optimize the isochronous conditions of the circulating particles for large acceptance, we install 10 trim coils to half of the dipole magnets. Individual injection system enables efficient injection of the produced rare RI into the ring one by one. With facilitating efficient extraction of the circulating particles, time-of-flight measurements can be performed to the each rare RI. Construction of the rare-RI ring was begun in the middle of the fiscal year 2012, and the ring is expected to be fully functional by 2015, when we can start the mass measurements for unknown masses.

  6. Rare-RI ring for mass measurements at RIBF

    NASA Astrophysics Data System (ADS)

    Ozawa, Akira

    2014-05-01

    The rare-RI (radioactive isotope) ring at the RIKEN RI Beam Factory is described. The main purpose of the rare-RI ring is to measure the mass of short-lived rare RI. In the rare-RI ring, the mass is determined by measuring the revolution time of each nucleus based on isochronous mass spectrometry. The rare-RI ring consists of six magnetic sectors, and each sector consists of four dipole magnets. To precisely optimize the isochronous conditions of the circulating particles for large acceptance, we install 10 trim coils to half of the dipole magnets. Individual injection system enables efficient injection of the produced rare RI into the ring one by one. With facilitating efficient extraction of the circulating particles, time-of-flight measurements can be performed to the each rare RI. Construction of the rare-RI ring was begun in the middle of the fiscal year 2012, and the ring is expected to be fully functional by 2015, when we can start the mass measurements for unknown masses.

  7. Final Report: Geoelectrical Measurement of Multi-Scale Mass Transfer Parameters

    SciTech Connect

    Haggerty, Roy; Day-Lewis, Fred; Singha, Kamini; Johnson, Timothy; Binley, Andrew; Lane, John

    2014-03-20

    Mass transfer affects contaminant transport and is thought to control the efficiency of aquifer remediation at a number of sites within the Department of Energy (DOE) complex. An improved understanding of mass transfer is critical to meeting the enormous scientific and engineering challenges currently facing DOE. Informed design of site remedies and long-term stewardship of radionuclide-contaminated sites will require new cost-effective laboratory and field techniques to measure the parameters controlling mass transfer spatially and across a range of scales. In this project, we sought to capitalize on the geophysical signatures of mass transfer. Previous numerical modeling and pilot-scale field experiments suggested that mass transfer produces a geoelectrical signature—a hysteretic relation between sampled (mobile-domain) fluid conductivity and bulk (mobile + immobile) conductivity—over a range of scales relevant to aquifer remediation. In this work, we investigated the geoelectrical signature of mass transfer during tracer transport in a series of controlled experiments to determine the operation of controlling parameters, and also investigated the use of complex-resistivity (CR) as a means of quantifying mass transfer parameters in situ without tracer experiments. In an add-on component to our grant, we additionally considered nuclear magnetic resonance (NMR) to help parse mobile from immobile porosities. Including the NMR component, our revised study objectives were to: 1. Develop and demonstrate geophysical approaches to measure mass-transfer parameters spatially and over a range of scales, including the combination of electrical resistivity monitoring, tracer tests, complex resistivity, nuclear magnetic resonance, and materials characterization; and 2. Provide mass-transfer estimates for improved understanding of contaminant fate and transport at DOE sites, such as uranium transport at the Hanford 300 Area. To achieve our objectives, we implemented a 3

  8. Multiple-Point Mass Flux Measurement System Using Rayleigh Scattering

    NASA Technical Reports Server (NTRS)

    Mielke, Amy F.; Elam, Kristie A.; Clem, Michelle M.

    2009-01-01

    A multiple-point Rayleigh scattering diagnostic is being developed to provide mass flux measurements in gas flows. Spectroscopic Rayleigh scattering is an established flow diagnostic that has the ability to provide simultaneous density, temperature, and velocity measurements. Rayleigh scattered light from a focused 18 Watt continuous-wave laser beam is directly imaged through a solid Fabry-Perot etalon onto a CCD detector which permits spectral analysis of the light. The spatial resolution of the measurements is governed by the locations of interference fringes, which can be changed by altering the etalon characteristics. A prototype system has been used to acquire data in a Mach 0.56 flow to demonstrate feasibility of using this system to provide mass flux measurements. Estimates of measurement uncertainty and recommendations for system improvements are presented

  9. Isotope ratio measurements by secondary ion mass spectrometry (SIMS) and glow discharge mass spectrometry (GDMS)

    NASA Astrophysics Data System (ADS)

    Betti, Maria

    2005-04-01

    The basic principles of secondary ion mass spectrometry and glow discharge mass spectrometry have been shortly revisited. The applications of both techniques as exploited for the isotope ratio measurements in several matrices have been reviewed. Emphasis has been given to research fields in expansions such as solar system studies, medicine, biology, environment and nuclear forensic. The characteristics of the two techniques are discussed in terms of sensitivity and methodology of quantification. Considerations on the different detection possibilities in SIMS are also presented.

  10. Measuring the mass of the W at the LHC

    SciTech Connect

    Keller, S.; Womersley, J.

    1997-01-01

    We explore the ability of the Large Hadron Collider to measure the mass of the W boson. We believe that a precision better than {approximately} 15 MeV could be attained, based on a year of operation at low luminosity (10{sup 33} cm{sup {minus}2} s{sup {minus}1}). If this is true, this measurement will be the world`s best determination of the W mass. We feel this interesting opportunity warrants investigation in more detail. 10 refs., 2 figs.

  11. A cooler Penning trap for the TITAN mass measurement facility

    SciTech Connect

    Chowdhury, U.; Kootte, B.; Good, M.; Lascar, D.; Schultz, B. E.; Dilling, J.; Gwinner, G.

    2015-01-09

    The TITAN facility at TRIUMF makes use of highly charged ions, charge-bred in an electron beam ion trap, to carry out accurate mass measurements on radioactive isotopes. We report on our progress to develop a cooler Penning trap, CPET, which aims at reducing the energy spread of the ions to ≈ 1 eV/charge prior to injection into the mass measurement trap. In off-line mode, we can now trap electron plasmas for minutes, and we observe the damping of the m = 1 diocotron plasma mode within ≈ 2 s.

  12. Fissile mass-multiplication factor correlation for Pu measurement

    SciTech Connect

    Lu, Ming-Shih; Teichmann, T.; De Ridder, P.; Verrecchia, G.P.D.; Chare, P.; Vocino, V.

    1993-06-01

    An empirical correlation between the fissile mass and the leakage multiplication factor, as determined by High Level Neutron Coincidence (HLNC) counting, was developed based on available measurement data. This correlation has been used successfully for the simulation of HLNC counting. With the singles count rate (totals), the correlation can be used to obtain a quick estimate of the plutonium mass of the sample in less time than required to measure the real coincidence count rate. The correlation can also be used to evaluate samples contaminated with ({alpha},n) sources such as fluorine.

  13. Mass Property Measurements of the Mars Science Laboratory Rover

    NASA Technical Reports Server (NTRS)

    Fields, Keith

    2012-01-01

    The NASA/JPL Mars Science Laboratory (MSL) spacecraft mass properties were measured on a spin balance table prior to launch. This paper discusses the requirements and issues encountered with the setup, qualification, and testing using the spin balance table, and the idiosyncrasies encountered with the test system. The final mass measurements were made in the Payload Hazardous Servicing Facility (PHSF) at Kennedy Space Center on the fully assembled and fueled spacecraft. This set of environmental tests required that the control system for the spin balance machine be at a remote location, which posed additional challenges to the operation of the machine

  14. Discovery and Mass Measurements of a Cold, Sub-Neptune Mass Planet and Its Host Star

    NASA Technical Reports Server (NTRS)

    Barry, Richard K., Jr.

    2011-01-01

    The gravitational microlensing exoplanet detection method is uniquely sensitive to cold, low-mass planets which orbit beyond the snow-line, where the most massive planets are thought to form. The early statistical results from microlensing indicate that Neptune-Saturn mass planets located beyond the snow-line are substantially more common than their counterparts in closer orbits that have found by the Doppler radial velocity method. We present the discovery of the planet MOA-2009-BLG-266Lb, which demonstrates that the gravitational microlensing method also has the capability to measure the masses of cold, low-mass planets. The mass measurements of the host star and the planet are made possible by the detection of the microlensing parallax signal due to the orbital motion or the Earth as well as observations from the EPOXI spacecraft in a Heliocentric orbit. The microlensing light curve indicates a planetary host star mass of M(sun) = 0.54 + / - 0.05M(sun) located at a distance of DL= 2.94 _ 0.21 kpc, orbited by a planet of mass mp= 9.8 +/-1.1M(Earth) with a semi-major axis of a = 3.1(+1.9-0.4)MAU.

  15. Modeling heat and mass transport phenomena at higher temperatures in solar distillation systems - The Chilton-Colburn analogy

    SciTech Connect

    Tsilingiris, P.T.

    2010-02-15

    In the present investigation efforts have been devoted towards developing an analysis suitable for heat and mass transfer processes modeling in solar distillation systems, when they are operating at higher temperatures. For this purpose the use of Lewis relation is not new although its validity is based on the assumptions of identical boundary layer concentration and temperature distributions, as well as low mass flux conditions, which are not usually met in solar distillation systems operating at higher temperatures associated with considerable mass transfer rates. The present analysis, taking into consideration these conditions and the temperature dependence of all pertinent thermophysical properties of the saturated binary mixture of water vapor and dry air, leads to the development of an improved predictive accuracy model. This model, having undergone successful first order validation against earlier reported measurements from the literature, appears to offer more accurate predictions of the transport processes and mass flow rate yield of solar stills when operated at elevated temperatures. (author)

  16. A four-probe thermal transport measurement method for nanostructures

    SciTech Connect

    Kim, Jaehyun; Ou, Eric; Sellan, Daniel P.; Shi, Li

    2015-04-15

    Several experimental techniques reported in recent years have enabled the measurement of thermal transport properties of nanostructures. However, eliminating the contact thermal resistance error from the measurement results has remained a critical challenge. Here, we report a different four-probe measurement method that can separately obtain both the intrinsic thermal conductance and the contact thermal resistance of individual nanostructures. The measurement device consists of four microfabricated, suspended metal lines that act as resistive heaters and thermometers, across which the nanostructure sample is assembled. The method takes advantage of the variation in the heat flow along the suspended nanostructure and across its contacts to the four suspended heater and thermometer lines, and uses sixteen sets of temperature and heat flow measurements to obtain nine of the thermal resistances in the measurement device and the nanostructure sample, including the intrinsic thermal resistance and the two contact thermal resistances to the middle suspended segment of the nanostructure. Two single crystalline Si nanowires with different cross sections are measured in this work to demonstrate the effectiveness of the method. This four-probe thermal transport measurement method can lead to future discoveries of unique size-dependent thermal transport phenomena in nanostructures and low-dimensional materials, in addition to providing reliable experimental data for calibrating theoretical models.

  17. Measurement of particle transport coefficients on Alcator C-Mod

    SciTech Connect

    Luke, T.C.T.

    1994-10-01

    The goal of this thesis was to study the behavior of the plasma transport during the divertor detachment in order to explain the central electron density rise. The measurement of particle transport coefficients requires sophisticated diagnostic tools. A two color interferometer system was developed and installed on Alcator C-Mod to measure the electron density with high spatial ({approx} 2 cm) and high temporal ({le} 1.0 ms) resolution. The system consists of 10 CO{sub 2} (10.6 {mu}m) and 4 HeNe (.6328 {mu}m) chords that are used to measure the line integrated density to within 0.08 CO{sub 2} degrees or 2.3 {times} 10{sup 16}m{sup {minus}2} theoretically. Using the two color interferometer, a series of gas puffing experiments were conducted. The density was varied above and below the threshold density for detachment at a constant magnetic field and plasma current. Using a gas modulation technique, the particle diffusion, D, and the convective velocity, V, were determined. Profiles were inverted using a SVD inversion and the transport coefficients were extracted with a time regression analysis and a transport simulation analysis. Results from each analysis were in good agreement. Measured profiles of the coefficients increased with the radius and the values were consistent with measurements from other experiments. The values exceeded neoclassical predictions by a factor of 10. The profiles also exhibited an inverse dependence with plasma density. The scaling of both attached and detached plasmas agreed well with this inverse scaling. This result and the lack of change in the energy and impurity transport indicate that there was no change in the underlying transport processes after detachment.

  18. Measuring consistent masses for 25 Milky Way globular clusters

    SciTech Connect

    Kimmig, Brian; Seth, Anil; Ivans, Inese I.; Anderton, Tim; Gregersen, Dylan; Strader, Jay; Caldwell, Nelson

    2015-02-01

    We present central velocity dispersions, masses, mass-to-light ratios (M/Ls ), and rotation strengths for 25 Galactic globular clusters (GCs). We derive radial velocities of 1951 stars in 12 GCs from single order spectra taken with Hectochelle on the MMT telescope. To this sample we add an analysis of available archival data of individual stars. For the full set of data we fit King models to derive consistent dynamical parameters for the clusters. We find good agreement between single-mass King models and the observed radial dispersion profiles. The large, uniform sample of dynamical masses we derive enables us to examine trends of M/L with cluster mass and metallicity. The overall values of M/L and the trends with mass and metallicity are consistent with existing measurements from a large sample of M31 clusters. This includes a clear trend of increasing M/L with cluster mass and lower than expected M/Ls for the metal-rich clusters. We find no clear trend of increasing rotation with increasing cluster metallicity suggested in previous work.

  19. Measurement of the mass difference between top and antitop quarks

    NASA Astrophysics Data System (ADS)

    Aaltonen, T.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J. A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Auerbach, B.; Aurisano, A.; Azfar, F.; Badgett, W.; Bae, T.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartos, P.; Bauce, M.; Bedeschi, F.; Behari, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Bhatti, A.; Bland, K. R.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brigliadori, L.; Bromberg, C.; Brucken, E.; Budagov, J.; Budd, H. S.; Burkett, K.; Busetto, G.; Bussey, P.; Butti, P.; Buzatu, A.; Calamba, A.; Camarda, S.; Campanelli, M.; Canelli, F.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Casal, B.; Casarsa, M.; Castro, A.; Catastini, P.; Cauz, D.; Cavaliere, V.; Cavalli-Sforza, M.; Cerri, A.; Cerrito, L.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Cho, K.; Chokheli, D.; Ciocci, M. A.; Clark, A.; Clarke, C.; Convery, M. E.; Conway, J.; Corbo, M.; Cordelli, M.; Cox, C. A.; Cox, D. J.; Cremonesi, M.; Cruz, D.; Cuevas, J.; Culbertson, R.; d'Ascenzo, N.; Datta, M.; De Barbaro, P.; Demortier, L.; Deninno, M.; Devoto, F.; d'Errico, M.; Di Canto, A.; Di Ruzza, B.; Dittmann, J. R.; D'Onofrio, M.; Donati, S.; Dorigo, M.; Driutti, A.; Ebina, K.; Edgar, R.; Elagin, A.; Erbacher, R.; Errede, S.; Esham, B.; Eusebi, R.; Farrington, S.; Fernández Ramos, J. P.; Field, R.; Flanagan, G.; Forrest, R.; Franklin, M.; Freeman, J. C.; Frisch, H.; Funakoshi, Y.; Garfinkel, A. F.; Garosi, P.; Gerberich, H.; Gerchtein, E.; Giagu, S.; Giakoumopoulou, V.; Gibson, K.; Ginsburg, C. M.; Giokaris, N.; Giromini, P.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldin, D.; Golossanov, A.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González López, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gramellini, E.; Grinstein, S.; Grosso-Pilcher, C.; Group, R. C.; Guimaraes da Costa, J.; Hahn, S. R.; Han, J. Y.; Happacher, F.; Hara, K.; Hare, M.; Harr, R. F.; Harrington-Taber, T.; Hatakeyama, K.; Hays, C.; Heinrich, J.; Herndon, M.; Hocker, A.; Hong, Z.; Hopkins, W.; Hou, S.; Hughes, R. E.; Husemann, U.; Huston, J.; Introzzi, G.; Iori, M.; Ivanov, A.; James, E.; Jang, D.; Jayatilaka, B.; Jeon, E. J.; Jindariani, S.; Jones, M.; Joo, K. K.; Jun, S. Y.; Junk, T. R.; Kambeitz, M.; Kamon, T.; Karchin, P. E.; Kasmi, A.; Kato, Y.; Ketchum, W.; Keung, J.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, J. E.; Kim, M. J.; Kim, S. B.; Kim, S. H.; Kim, Y. K.; Kim, Y. J.; Kimura, N.; Kirby, M.; Knoepfel, K.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Kotwal, A. V.; Kreps, M.; Kroll, J.; Kruse, M.; Kuhr, T.; Kurata, M.; Laasanen, A. T.; Lammel, S.; Lancaster, M.; Lannon, K.; Latino, G.; Lee, H. S.; Lee, J. S.; Leo, S.; Leone, S.; Lewis, J. D.; Limosani, A.; Lipeles, E.; Liu, H.; Liu, Q.; Liu, T.; Lockwitz, S.; Loginov, A.; Lucchesi, D.; Lueck, J.; Lujan, P.; Lukens, P.; Lungu, G.; Lys, J.; Lysak, R.; Madrak, R.; Maestro, P.; Malik, S.; Manca, G.; Manousakis-Katsikakis, A.; Margaroli, F.; Marino, P.; Martínez, M.; Matera, K.; Mattson, M. E.; Mazzacane, A.; Mazzanti, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Mesropian, C.; Miao, T.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Moon, C. S.; Moore, R.; Morello, M. J.; Mukherjee, A.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nakano, I.; Napier, A.; Nett, J.; Neu, C.; Nigmanov, T.; Nodulman, L.; Noh, S. Y.; Norniella, O.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Ortolan, L.; Pagliarone, C.; Palencia, E.; Palni, P.; Papadimitriou, V.; Parker, W.; Pauletta, G.; Paulini, M.; Paus, C.; Phillips, T. J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pondrom, L.; Poprocki, S.; Potamianos, K.; Prokoshin, F.; Pranko, A.; Ptohos, F.; Punzi, G.; Ranjan, N.; Redondo Fernández, I.; Renton, P.; Rescigno, M.; Riddick, T.; Rimondi, F.; Ristori, L.; Robson, A.; Rodriguez, T.; Rolli, S.; Ronzani, M.; Roser, R.; Rosner, J. L.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Safonov, A.; Sakumoto, W. K.; Sakurai, Y.; Santi, L.; Sato, K.; Saveliev, V.; Savoy-Navarro, A.; Schlabach, P.; Schmidt, E. E.; Schwarz, T.; Scodellaro, L.; Scuri, F.; Seidel, S.; Seiya, Y.; Semenov, A.; Sforza, F.; Shalhout, S. Z.; Shears, T.; Shepard, P. F.; Shimojima, M.; Shochet, M.; Shreyber-Tecker, I.; Simonenko, A.; Sinervo, P.; Sliwa, K.; Smith, J. R.; Snider, F. D.; Sorin, V.; Song, H.; Stancari, M.; Denis, R. St.; Stelzer, B.; Stelzer-Chilton, O.; Stentz, D.; Strologas, J.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P. K.; Thom, J.; Thomson, E.; Thukral, V.; Toback, D.; Tokar, S.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Ukegawa, F.; Uozumi, S.; Vázquez, F.; Velev, G.; Vellidis, C.; Vernieri, C.; Vidal, M.; Vilar, R.; Vizán, J.; Vogel, M.; Volpi, G.; Wagner, P.; Wallny, R.; Wang, S. M.; Warburton, A.; Waters, D.; Wester, W. C., III; Whiteson, D.; Wicklund, A. B.; Wilbur, S.; Williams, H. H.; Wilson, J. S.; Wilson, P.; Winer, B. L.; Wittich, P.; Wolbers, S.; Wolfe, H.; Wright, T.; Wu, X.; Wu, Z.; Yamamoto, K.; Yamato, D.; Yang, T.; Yang, U. K.; Yang, Y. C.; Yao, W.-M.; Yeh, G. P.; Yi, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Yu, G. B.; Yu, I.; Zanetti, A. M.; Zeng, Y.; Zhou, C.; Zucchelli, S.

    2013-03-01

    We present a measurement of the mass difference between top (t) and antitop (t¯) quarks using tt¯ candidate events reconstructed in the final state with one lepton and multiple jets. We use the full data set of Tevatron s=1.96TeV proton-antiproton collisions recorded by the CDF II detector, corresponding to an integrated luminosity of 8.7fb-1. We estimate event by event the mass difference to construct templates for top pair signal events and background events. The resulting mass difference distribution in data compared to signal and background templates using a likelihood fit yields ΔMtop=Mt-Mt¯=-1.95±1.11(stat)±0.59(syst)GeV/c2 and is in agreement with the standard model prediction of no mass difference.

  20. Prospects for Measurement of the Neutrino Mass Hierarchy

    NASA Astrophysics Data System (ADS)

    Patterson, R. B.

    2015-10-01

    The unknown neutrino mass hierarchy—whether the ν3 mass eigenstate is the heaviest or the lightest—represents a major gap in our knowledge of neutrino properties. Determining the hierarchy is a critical step toward further precision measurements in the neutrino sector. The hierarchy is also central to interpreting the next generation of neutrinoless double-β decay results, plays a role in numerous cosmological and astrophysical questions, and serves as a powerful model discriminant for theories of neutrino mass generation and unification. Various current and planned experiments claim sensitivity for establishing the neutrino mass hierarchy. I review the most promising of these here, paying special attention to points of concern and consolidating the projected sensitivities into an outlook for the years ahead.

  1. Identification and Quantitative Measurements of Chemical Species by Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Zondlo, Mark A.; Bomse, David S.

    2005-01-01

    The development of a miniature gas chromatograph/mass spectrometer system for the measurement of chemical species of interest to combustion is described. The completed system is a fully-contained, automated instrument consisting of a sampling inlet, a small-scale gas chromatograph, a miniature, quadrupole mass spectrometer, vacuum pumps, and software. A pair of computer-driven valves controls the gas sampling and introduction to the chromatographic column. The column has a stainless steel exterior and a silica interior, and contains an adsorbent of that is used to separate organic species. The detection system is based on a quadrupole mass spectrometer consisting of a micropole array, electrometer, and a computer interface. The vacuum system has two miniature pumps to maintain the low pressure needed for the mass spectrometer. A laptop computer uses custom software to control the entire system and collect the data. In a laboratory demonstration, the system separated calibration mixtures containing 1000 ppm of alkanes and alkenes.

  2. Damage detection using experimentally measured mass and stiffness matrices

    NASA Technical Reports Server (NTRS)

    Peterson, L. D.; Alvin, K. F.; Doebling, S. W.; Park, K. C.

    1993-01-01

    A method is presented for locating physical damage or change in a structure using experimentally measured mass and stiffness matrices. The approach uses a recently developed algorithm for transforming a state-space realization into a second order structural model with physical displacements as the generalized coordinates. This is accomplished by first rotating a state-space model of the identified structural dynamics into modal coordinates and approximating the mass normalized modal vectors for the output measurement set. Next, the physical mass, damping and stiffness matrices are synthesized directly from the measured modal parameters. This yields experimental mass and stiffness matrices for the structure without the use of a finite element model or a numerical search. The computed mass and stiffness are asymptotically equivalent to a static condensation of the global physical coordinate model. Techniques for solving the inverse connectivity problem are then developed whereby it is possible to assess the stiffness in a region of the structure bounded by several sensors. Applications to both simulated data and experimental data are used to discuss the effectiveness of the approach.

  3. Damage detection using experimentally measured mass and stiffness matrices

    NASA Astrophysics Data System (ADS)

    Peterson, L. D.; Alvin, K. F.; Doebling, S. W.; Park, K. C.

    1993-04-01

    A method is presented for locating physical damage or change in a structure using experimentally measured mass and stiffness matrices. The approach uses a recently developed algorithm for transforming a state-space realization into a second order structural model with physical displacements as the generalized coordinates. This is accomplished by first rotating a state-space model of the identified structural dynamics into modal coordinates and approximating the mass normalized modal vectors for the output measurement set. Next, the physical mass, damping and stiffness matrices are synthesized directly from the measured modal parameters. This yields experimental mass and stiffness matrices for the structure without the use of a finite element model or a numerical search. The computed mass and stiffness are asymptotically equivalent to a static condensation of the global physical coordinate model. Techniques for solving the inverse connectivity problem are then developed whereby it is possible to assess the stiffness in a region of the structure bounded by several sensors. Applications to both simulated data and experimental data are used to discuss the effectiveness of the approach.

  4. Transport of a lattice gas under continuous measurement

    NASA Astrophysics Data System (ADS)

    Cheung, Hil F. H.; Patil, Yogesh Sharad; Madjarov, Ivaylo S.; Chen, Huiyao Y.; Vengalattore, Mukund

    2016-05-01

    The act of measurement has a profound consequence on a quantum system. While this backaction has hitherto been discussed as a limitation to the precision of measurements, it is increasingly being appreciated that measurement backaction is a powerful means of quantum control. We have previously demonstrated that backaction from position measurement can modify the coherent tunneling rate of a lattice gas through the Quantum Zeno effect. By suitably designing measurement landscapes we can control the transport properties of the lattice gas. We describe a quantitative study of lattice gas dynamics under continuous quantum measurement in the context of a quantum to classical transition where the atom dynamics goes from a quantum walk at low measurement strengths to classical diffusion at high measurement strengths. We further discuss the prospect of using disorder measurement landscapes to realize a new form of Anderson localization. This work is supported by the ARO MURI on non-equilibrium dynamics.

  5. Physics-based agent to simulant correlations for vapor phase mass transport.

    PubMed

    Willis, Matthew P; Varady, Mark J; Pearl, Thomas P; Fouse, Janet C; Riley, Patrick C; Mantooth, Brent A; Lalain, Teri A

    2013-12-15

    Chemical warfare agent simulants are often used as an agent surrogate to perform environmental testing, mitigating exposure hazards. This work specifically addresses the assessment of downwind agent vapor concentration resulting from an evaporating simulant droplet. A previously developed methodology was used to estimate the mass diffusivities of the chemical warfare agent simulants methyl salicylate, 2-chloroethyl ethyl sulfide, di-ethyl malonate, and chloroethyl phenyl sulfide. Along with the diffusivity of the chemical warfare agent bis(2-chloroethyl) sulfide, the simulant diffusivities were used in an advection-diffusion model to predict the vapor concentrations downwind from an evaporating droplet of each chemical at various wind velocities and temperatures. The results demonstrate that the simulant-to-agent concentration ratio and the corresponding vapor pressure ratio are equivalent under certain conditions. Specifically, the relationship is valid within ranges of measurement locations relative to the evaporating droplet and observation times. The valid ranges depend on the relative transport properties of the agent and simulant, and whether vapor transport is diffusion or advection dominant.

  6. 3D nonrigid registration via optimal mass transport on the GPU

    PubMed Central

    Rehman, Tauseef ur; Haber, Eldad; Pryor, Gallagher; Melonakos, John; Tannenbaum, Allen

    2009-01-01

    In this paper, we present a new computationally efficient numerical scheme for the minimizing flow approach for optimal mass transport (OMT) with applications to non-rigid 3D image registration. The approach utilizes all of the gray-scale data in both images, and the optimal mapping from image A to image B is the inverse of the optimal mapping from B to A. Further, no landmarks need to be specified, and the minimizer of the distance functional involved is unique. Our implementation also employs multigrid, and parallel methodologies on a consumer graphics processing unit (GPU) for fast computation. Although computing the optimal map has been shown to be computationally expensive in the past, we show that our approach is orders of magnitude faster then previous work and is capable of finding transport maps with optimality measures (mean curl) previously unattainable by other works (which directly influences the accuracy of registration). We give results where the algorithm was used to compute non-rigid registrations of 3D synthetic data as well as intra-patient pre-operative and post-operative 3D brain MRI datasets. PMID:19135403

  7. Resonance Ionization Mass Spectrometry System for Measurement of Environmental Samples

    NASA Astrophysics Data System (ADS)

    Pibida, L.; McMahon, C. A.; Nörtershäuser, W.; Bushaw, B. A.

    2002-10-01

    A resonance ionization mass spectrometry (RIMS) system has been developed at the National Institute of Standards and Technology (NIST) for sensitive and selective determination of radio-cesium in the environment. The overall efficiency was determined to be 4×10-7 with a combined (laser and mass spectrometer) selectivity of 108 for both 135Cs and 137Cs with respect to 133Cs. RIMS isotopic ratio measurements of 135Cs/ 137Cs were performed on a nuclear fuel burn-up sample and compared to measurements on a similar system at Pacific Northwest National Laboratory (PNNL) and to conventional thermal ionization mass spectrometry (TIMS). Results of preliminary RIMS investigations on a freshwater lake sediment sample are also discussed.

  8. A New Top Mass Measurement in The Dilepton Channel

    SciTech Connect

    Trovato, Marco; /INFN, Pisa /Pisa U.

    2008-01-01

    The top quark discovery completed the present picture of the fundamental constituents of the nature. Since then, the Collider Detector at Fermilab and D0 Collaborations have been spending great efforts to measure its properties better. About 30 times larger than the second heaviest quark, the mass of the top has been measured with increased statistic and more and more sophisticated techniques in order to reduce as much as possible its uncertainty. This is because the top is expected to play a fundamental role in the Standard Model. The value of its mass sets boundaries on the mass of the unobserved Higgs boson, and perhaps more appealing, studies of its properties might lead to the discovery of new physics.

  9. Mass measurements on radioactive isotopes with a Penning trap mass spectrometer

    SciTech Connect

    Bollen, G.; Ames, F.; Schark, E.; Audi, G.; Lunney, D.; Saint Simon, M. de; Beck, D.; Herfurth, F.; Kluge, H.-J.; Kohl, A.; Schwarz, S.; Moore, R. B.; Szerypo, J.

    1999-01-15

    Penning trap mass measurements on short-lived isotopes are performed with the ISOLTRAP mass spectrometer at the radioactive beam facility ISOLDE/CERN. In the last years the applicability of the spectrometer has been considerably extended by the installation of an RFQ trap ion beam buncher and a new cooler Penning trap, which is operated as an isobar separator. These improvements allowed for the first time measurements on isotopes of rare earth elements and on isotopes with Z=80-85. In all cases an accuracy of {delta}m/m{approx_equal}1{center_dot}10{sup -7} was achieved.

  10. Microwave measurement of the mass of frozen hydrogen pellets

    DOEpatents

    Talanker, Vera; Greenwald, Martin

    1990-01-01

    A nondestructive apparatus and method for measuring the mass of a moving object, based on the perturbation of the dielectric character of a resonant microwave cavity caused by the object passing through the cavity. An oscillator circuit is formed with a resonant cavity in a positive feedback loop of a microwave power amplifier. The moving object perturbs the resonant characteristics of the cavity causing a shift in the operating frequency of the oscillator proportional to the ratio of the pellet volume to the volume of the cavity. Signals from the cavity oscillation are mixed with a local oscillator. Then the IF frequency from the mixer is measured thereby providing a direct measurement of pellet mass based upon known physical properties and relationships. This apparatus and method is particularly adapted for the measurement of frozen hydrogen pellets.

  11. Improvements to TITAN's mass measurement and decay spectroscopy capabilities

    NASA Astrophysics Data System (ADS)

    Lascar, D.; Kwiatkowski, A. A.; Alanssari, M.; Chowdhury, U.; Even, J.; Finlay, A.; Gallant, A. T.; Good, M.; Klawitter, R.; Kootte, B.; Li, T.; Leach, K. G.; Lennarz, A.; Leistenschneider, E.; Mayer, A. J.; Schultz, B. E.; Schupp, R.; Short, D. A.; Andreoiu, C.; Dilling, J.; Gwinner, G.

    2016-06-01

    The study of nuclei farther from the valley of β -stability than ever before goes hand-in-hand with shorter-lived nuclei produced in smaller abundances than their less exotic counterparts. The measurement, to high precision, of nuclear masses therefore requires innovations in technique in order to keep up. TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN) facility deploys three ion traps, with a fourth in the commissioning phase, to perform and support Penning trap mass spectrometry and in-trap decay spectroscopy on some of the shortest-lived nuclei ever studied. We report on recent advances and updates to the TITAN facility since the 2012 EMIS conference. TITAN's charge breeding capabilities have been improved and in-trap decay spectroscopy can be performed in TITAN's Electron Beam Ion Trap (EBIT). Higher charge states can improve the precision of mass measurements, reduce the beam-time requirements for a given measurement, improve beam purity, and open the door to access isotopes not available from the ISOL method via in-trap decay and recapture. This was recently demonstrated during TITAN's mass measurement of 30 Al. The EBIT's decay spectroscopy setup was commissioned with a successful branching ratio and half-life measurement of 124 Cs. Charge breeding in the EBIT increases the energy spread of the ion bunch sent to the Penning trap for mass measurement, so a new Cooler PEnning Trap (CPET), which aims to cool highly charged ions with an electron plasma, is undergoing offline commissioning. Already CPET has demonstrated the trapping and self-cooling of a room-temperature electron plasma that was stored for several minutes. A new detector has been installed inside the CPET magnetic field which will allow for in-magnet charged particle detection.

  12. Temporal variability of mass transport across Canary Islands Channels

    NASA Astrophysics Data System (ADS)

    Marrero-Díaz, Ángeles; Rodríguez-Santana, Ángel; José Machín, Francisco; García-Weil, Luis; Sangrà, Pablo; Vélez-Belchí, Pedro; Fraile-Nuez, Eugenio

    2014-05-01

    The equatorward flowing Canary Current (CC) is the main feature of the circulation in the Canary Islands region. The CC flow perturbation by the Canary Islands originate the Canary Eddy Corridor which is the major pathway for long lived eddies in the subtropical North Atlantic (Sangrà et al., 2009, DSR). Therefore the variability of the CC passing through the Canary Archipelago will have both local and regional importance. Past studies on the CC variability trough the Canary Islands point out a clearly seasonal variability (Fraile-Nuez et al, 2010 (JGR); Hernández-Guerra et al, 2002 (DSR)). However those studies where focused on the eastern islands channels missing the variability through the western island channels which are the main source of long lived eddies. In order to fill this gap from November 2012 until September 2013 we conducted trimonthly surveys crossing the whole islands channels using opportunity ships (Naviera Armas Ferries). XBT and XCTD where launched along the cross channels transects. Additionally a closed box circling the Archipelago was performed on October 2013 as part of the cruise RAPROCAN-2013 (IEO) using also XBT and XCTD. Dynamical variables where derived inferring salinity from S(T,p) analytical relationships for the region updated with new XCTD data. High resolution, vertical sections of temperature, potential density, geostrophic velocity and transport where obtained. Our preliminary results suggest that the CC suffer a noticeable acceleration in those islands channels where eddy shedding is more frequent. They also indicate a clearly seasonal variability of the flows passing the islands channels. With this regard we observed significant differences on the obtained seasonal variability with respect the cited past studies on the eastern islands channel (Lanzarote / Fuerteventura - Africa coast). This work was co-funded by Canary Government (TRAMIC project: PROID20100092) and the European Union (FEDER).

  13. Fram Strait and Greenland Sea transports, water masses, and water mass transformations 1999-2010 (and beyond)

    NASA Astrophysics Data System (ADS)

    Marnela, Marika; Rudels, Bert; Goszczko, Ilona; Beszczynska-Möller, Agnieszka; Schauer, Ursula

    2016-04-01

    The exchanges between the Nordic Seas and the Arctic Ocean are important for the ocean circulation and climate. Transports are here estimated using summer hydrographic data from the Greenland Sea and the Fram Strait. Geostrophic transports are computed from hydrographic sections at 75°N in the Greenland Sea and at about 79°N in the Fram Strait. Geostrophic velocities are adjusted with summer velocities derived from Argo floats, and four conservation constraints are applied to a box closed by the two sections. The estimated net volume transports are 0.8 ± 1.5 Sv southward. Net freshwater transports through the Greenland Sea section are estimated at 54 ± 20 mSv and through the Fram Strait section at 66 ± 9 mSv. Heat loss in the area between the two sections is estimated at 9 ± 12 TW. Convection depths in the Greenland Sea are estimated from observations and vary between about 200 and 2000 dbar showing no trend. Water mass properties in the Greenland Sea are affected both by convection and lateral mixing. Vertical mixing is estimated from hydrography and based on it about 1 Sv of diluted Arctic Ocean waters are estimated to enter the Greenland Sea. The properties of Atlantic, intermediate, and deep waters are studied. Deep water properties are defined using water mass triangles and are subject to decadal changes.

  14. Mass measurement using energy spectra in three-body decays

    NASA Astrophysics Data System (ADS)

    Agashe, Kaustubh; Franceschini, Roberto; Kim, Doojin; Wardlow, Kyle

    2016-05-01

    In previous works we have demonstrated how the energy distribution of massless decay products in two body decays can be used to measure the mass of decaying particles. In this work we show how such results can be generalized to the case of multi-body decays. The key ideas that allow us to deal with multi-body final states are an extension of our previous results to the case of massive decay products and the factorization of the multi-body phase space. The mass measurement strategy that we propose is distinct from alternative methods because it does not require an accurate reconstruction of the entire event, as it does not involve, for instance, the missing transverse momentum, but rather requires measuring only the visible decay products of the decay of interest. To demonstrate the general strategy, we study a supersymmetric model wherein pair-produced gluinos each decay to a stable neutralino and a bottom quark-antiquark pair via an off -shell bottom squark. The combinatorial background stemming from the indistinguishable visible final states on both decay sides can be treated by an "event mixing" technique, the performance of which is discussed in detail. Taking into account dominant backgrounds, we are able to show that the mass of the gluino and, in favorable cases, that of the neutralino can be determined by this mass measurement strategy.

  15. Canadian Penning Trap Mass Measurements using a Position Sensitive MCP

    NASA Astrophysics Data System (ADS)

    Kuta, Trenton; Aprahamian, Ani; Marley, Scott; Nystrom, Andrew; Clark, Jason; Perez Galvan, Adrian; Hirsh, Tsviki; Savard, Guy; Orford, Rodney; Morgan, Graeme

    2015-10-01

    The primary focus of the Canadian Penning Trap (CPT) located at Argonne National Lab is to determine the masses of various isotopes produced in the spontaneous fission of Californium. Currently, the CPT is operating in conjunction with CARIBU at the ATLAS facility in an attempt to measure neutron-rich nuclei produced by a 1.5 Curie source of Californium 252. The masses of nuclei produced in fission is accomplished by measuring the cyclotron frequency of the isotopes circling within the trap. This frequency is determined by a position sensitive MCP, which records the relative position of the isotope in the trap at different times. Using these position changes over time in connection with a center spot, angles between these positions are calculated and used to determine the frequency. Most of the work currently being conducted on the CPT is focused on the precision of these frequency measurements. The use of traps has revolutionized the measurements of nuclear masses to very high precision. The optimization methods employed here include focusing the beam in order to reduce the spread on the position of the isotope as well as the tuning of the MR-ToF, a mass separator that is intended on removing contaminants in the beam. This work was supported by the nuclear Grant PHY-1419765 for the University of Notre Dame.

  16. Mass measurement using energy spectra in three-body decays

    DOE PAGES

    Agashe, Kaustubh; Franceschini, Roberto; Kim, Doojin; Wardlow, Kyle

    2016-05-24

    In previous works we have demonstrated how the energy distribution of massless decay products in two body decays can be used to measure the mass of decaying particles. In this study, we show how such results can be generalized to the case of multi-body decays. The key ideas that allow us to deal with multi-body final states are an extension of our previous results to the case of massive decay products and the factorization of the multi-body phase space. The mass measurement strategy that we propose is distinct from alternative methods because it does not require an accurate reconstruction ofmore » the entire event, as it does not involve, for instance, the missing transverse momentum, but rather requires measuring only the visible decay products of the decay of interest. To demonstrate the general strategy, we study a supersymmetric model wherein pair-produced gluinos each decay to a stable neutralino and a bottom quark-antiquark pair via an off -shell bottom squark. The combinatorial background stemming from the indistinguishable visible final states on both decay sides can be treated by an “event mixing” technique, the performance of which is discussed in detail. In conclusion, taking into account dominant backgrounds, we are able to show that the mass of the gluino and, in favorable cases, that of the neutralino can be determined by this mass measurement strategy.« less

  17. Radial ion transport measurements in a nonaxisymmetric magnetic mirror

    SciTech Connect

    Goodman, D.L.; Petty, C.C.; Post, R.S. )

    1990-09-01

    Experimental radial ion transport rates and diffusion coefficients are presented for the Constance-B magnetic mirror (Phys. Rev. Lett. {bold 58}, 1853 (1987)). The transport experiments are performed by measuring steady state equilibrium radial profiles of plasma density, ionization source, end loss current, electric field, electron temperature, and ion temperature. A charge coupled device (CCD) camera system (Rev. Sci. Instrum. {bold 60}, 2835 (1989)) is used to measure the two-dimensional radial density, source, and electron temperature profiles. End loss diagnostics including movable Faraday cups, electrostatic end loss analyzers, and an ion time-of-flight analyzer (Rev. Sci. Instrum. {bold 59}, 601 (1988)) are used to measure radial profiles of potential and ion temperature. The ion confinement time perpendicular to the magnetic field is found to be an order of magnitude shorter than predicted by classical and neoclassical transport theories. The radial profiles of the perpendicular diffusion coefficient ({ital D}{sub {perpendicular}}) are presented for hydrogen, helium, and argon plasmas. The coefficients are a factor of 10 larger than the maximum classical and neoclassical coefficients in all three plasmas. Plasma fluctuations resulting from whistler mode microinstability (Phys. Rev. Lett. {bold 59}, 1821 (1987)) as well as nonaxisymmetric potentials are suggested as possible explanations for the experimentally measured radial transport rate.

  18. Mass Spectrometric Measurement of Martian Krypton and Xenon Isotopic Abundance

    NASA Technical Reports Server (NTRS)

    Mahaffy, P.; Mauersberger, K.

    1993-01-01

    The Viking gas chromatograph mass spectrometer experiment provided significant data on the atmospheric composition at the surface of Mars, including measurements of several isotope ratios. However, the limited dynamic range of this mass spectrometer resulted in marginal measurements for the important Kr and Xe isotopic abundance. The Xe-129 to Xe-132 ratio was measured with an uncertainty of 70%, but none of the other isotope ratios for these species were obtained. Accurate measurement of the Xe and Kr isotopic abundance in this atmosphere provides an important data point in testing theories of planetary formation and atmospheric evolution. The measurement is also essential for a stringent test for the Martian origin of the SNC meteorites, since the Kr and Xe fractionation pattern seen in gas trapped in glassy nodules of an SNC (EETA 79001) is unlike any other known solar system resevoir. Current flight mass spectrometer designs combined with the new technology of a high-performance vacuum pumping system show promise for a substantial increase in gas throughput and the dynamic range required to accurately measure these trace species. Various aspects of this new technology are discussed.

  19. Workplace aerosol mass concentration measurement using optical particle counters.

    PubMed

    Görner, Peter; Simon, Xavier; Bémer, Denis; Lidén, Göran

    2012-02-01

    Direct-reading aerosol measurement usually uses the optical properties of airborne particles to detect and measure particle concentration. In the case of occupational hygiene, mass concentration measurement is often required. Two aerosol monitoring methods are based on the principle of light scattering: optical particle counting (OPC) and photometry. The former analyses the light scattered by a single particle, the latter by a cloud of particles. Both methods need calibration to transform the quantity of scattered light detected into particle concentration. Photometers are simpler to use and can be directly calibrated to measure mass concentration. However, their response varies not only with aerosol concentration but also with particle size distribution, which frequently contributes to biased measurement. Optical particle counters directly measure the particle number concentration and particle size that allows assessment of the particle mass provided the particles are spherical and of known density. An integrating algorithm is used to calculate the mass concentration of any conventional health-related aerosol fraction. The concentrations calculated thus have been compared with simultaneous measurements by conventional gravimetric sampling to check the possibility of field OPC calibration with real workplace aerosols with a view to further monitoring particle mass concentration. Aerosol concentrations were measured in the food industry using the OPC GRIMM® 1.108 and the CIP 10-Inhalable and CIP 10-Respirable (ARELCO®) aerosol samplers while meat sausages were being brushed and coated with calcium carbonate. Previously, the original OPC inlet had been adapted to sample inhalable aerosol. A mixed aerosol of calcium carbonate and fungi spores was present in the workplace. The OPC particle-size distribution and an estimated average particle density of both aerosol components were used to calculate the mass concentration. The inhalable and respirable aerosol fractions

  20. Workplace aerosol mass concentration measurement using optical particle counters.

    PubMed

    Görner, Peter; Simon, Xavier; Bémer, Denis; Lidén, Göran

    2012-02-01

    Direct-reading aerosol measurement usually uses the optical properties of airborne particles to detect and measure particle concentration. In the case of occupational hygiene, mass concentration measurement is often required. Two aerosol monitoring methods are based on the principle of light scattering: optical particle counting (OPC) and photometry. The former analyses the light scattered by a single particle, the latter by a cloud of particles. Both methods need calibration to transform the quantity of scattered light detected into particle concentration. Photometers are simpler to use and can be directly calibrated to measure mass concentration. However, their response varies not only with aerosol concentration but also with particle size distribution, which frequently contributes to biased measurement. Optical particle counters directly measure the particle number concentration and particle size that allows assessment of the particle mass provided the particles are spherical and of known density. An integrating algorithm is used to calculate the mass concentration of any conventional health-related aerosol fraction. The concentrations calculated thus have been compared with simultaneous measurements by conventional gravimetric sampling to check the possibility of field OPC calibration with real workplace aerosols with a view to further monitoring particle mass concentration. Aerosol concentrations were measured in the food industry using the OPC GRIMM® 1.108 and the CIP 10-Inhalable and CIP 10-Respirable (ARELCO®) aerosol samplers while meat sausages were being brushed and coated with calcium carbonate. Previously, the original OPC inlet had been adapted to sample inhalable aerosol. A mixed aerosol of calcium carbonate and fungi spores was present in the workplace. The OPC particle-size distribution and an estimated average particle density of both aerosol components were used to calculate the mass concentration. The inhalable and respirable aerosol fractions

  1. Recent Developments in Graphene-Based Membranes: Structure, Mass-Transport Mechanism and Potential Applications.

    PubMed

    Sun, Pengzhan; Wang, Kunlin; Zhu, Hongwei

    2016-03-23

    Significant achievements have been made on the development of next-generation filtration and separation membranes using graphene materials, as graphene-based membranes can afford numerous novel mass-transport properties that are not possible in state-of-art commercial membranes, making them promising in areas such as membrane separation, water desalination, proton conductors, energy storage and conversion, etc. The latest developments on understanding mass transport through graphene-based membranes, including perfect graphene lattice, nanoporous graphene and graphene oxide membranes are reviewed here in relation to their potential applications. A summary and outlook is further provided on the opportunities and challenges in this arising field. The aspects discussed may enable researchers to better understand the mass-transport mechanism and to optimize the synthesis of graphene-based membranes toward large-scale production for a wide range of applications.

  2. Recent Developments in Graphene-Based Membranes: Structure, Mass-Transport Mechanism and Potential Applications.

    PubMed

    Sun, Pengzhan; Wang, Kunlin; Zhu, Hongwei

    2016-03-23

    Significant achievements have been made on the development of next-generation filtration and separation membranes using graphene materials, as graphene-based membranes can afford numerous novel mass-transport properties that are not possible in state-of-art commercial membranes, making them promising in areas such as membrane separation, water desalination, proton conductors, energy storage and conversion, etc. The latest developments on understanding mass transport through graphene-based membranes, including perfect graphene lattice, nanoporous graphene and graphene oxide membranes are reviewed here in relation to their potential applications. A summary and outlook is further provided on the opportunities and challenges in this arising field. The aspects discussed may enable researchers to better understand the mass-transport mechanism and to optimize the synthesis of graphene-based membranes toward large-scale production for a wide range of applications. PMID:26797529

  3. A PERFECT MATCH CONDITION FOR POINT-SET MATCHING PROBLEMS USING THE OPTIMAL MASS TRANSPORT APPROACH

    PubMed Central

    CHEN, PENGWEN; LIN, CHING-LONG; CHERN, I-LIANG

    2013-01-01

    We study the performance of optimal mass transport-based methods applied to point-set matching problems. The present study, which is based on the L2 mass transport cost, states that perfect matches always occur when the product of the point-set cardinality and the norm of the curl of the non-rigid deformation field does not exceed some constant. This analytic result is justified by a numerical study of matching two sets of pulmonary vascular tree branch points whose displacement is caused by the lung volume changes in the same human subject. The nearly perfect match performance verifies the effectiveness of this mass transport-based approach. PMID:23687536

  4. Mass transport at infinite regular arrays of microband electrodes submitted to natural convection: theory and experiments.

    PubMed

    Pebay, Cécile; Sella, Catherine; Thouin, Laurent; Amatore, Christian

    2013-12-17

    Mass transport at infinite regular arrays of microband electrodes was investigated theoretically and experimentally in unstirred solutions. Even in the absence of forced hydrodynamics, natural convection limits the convection-free domain up to which diffusion layers may expand. Hence, several regimes of mass transport may take place according to the electrode size, gap between electrodes, time scale of the experiment, and amplitude of natural convection. They were identified through simulation by establishing zone diagrams that allowed all relative contributions to mass transport to be delineated. Dynamic and steady-state regimes were compared to those achieved at single microband electrodes. These results were validated experimentally by monitoring the chronoamperometric responses of arrays with different ratios of electrode width to gap distance and by mapping steady-state concentration profiles above their surface through scanning electrochemical microscopy. PMID:24283775

  5. What controls the mass transport by mode-2 internal solitary-like waves?

    NASA Astrophysics Data System (ADS)

    Deepwell, David; Stastna, Marek

    2016-04-01

    Horizontally propagating internal waves are a regular occurrence in the coastal ocean. Their most commonly observed vertical structure is mode-1 in which isopycnals rise and fall in concert at all depths. Second mode waves, where isopycnals expand from and contract toward the pycnocline centre, have been found in recent observations to occur more frequently than previously thought. For the more common convex configuration, these waves mix the pycnocline, and under certain conditions form recirculating cores which efficiently transport material. In the laboratory, mode-2 waves are easily formed by releasing a mixed region into an ambient stratification. Using high resolution, three dimensional, direct numerical simulations of a laboratory configuration we describe the mass transport efficiency of mode-2 waves under a variety of different parameter regimes and initializations. We identify pycnocline configurations for which transport is especially efficient, and explore the structure of recirculating cores during their formation, propagation and disintegration and its implications on mass transport.

  6. Heat transport measurements in turbulent rotating Rayleigh-Benard convection

    SciTech Connect

    Ecke, Robert E; Liu, Yuanming

    2008-01-01

    We present experimental heat transport measurements of turbulent Rayleigh-Benard convection with rotation about a vertical axis. The fluid, water with Prandtl number ({sigma}) about 6, was confined in a cell which had a square cross section of 7.3 cm x 7.3 cm and a height of 9.4 cm. Heat transport was measured for Rayleigh numbers 2 x 10{sup 5} < Ra < 5 x 10{sup 8} and Taylor numbers 0 < Ta < 5 x 10{sup 9}. We show the variation of normalized heat transport, the Nusselt number, at fixed dimensional rotation rate {Omega}{sub D}, at fixed Ra varying Ta, at fixed Ta varying Ra, and at fixed Rossby number Ro. The scaling of heat transport in the range 10{sup 7} to about 10{sup 9} is roughly 0.29 with a Ro dependent coefficient or equivalently is also well fit by a combination of power laws of the form a Ra{sup 1/5} + b Ra{sup 1/3} . The range of Ra is not sufficient to differentiate single power law or combined power law scaling. The overall impact of rotation on heat transport in turbulent convection is assessed.

  7. Development of density and mass flow rate measurement technologies for slush hydrogen

    NASA Astrophysics Data System (ADS)

    Ohira, Katsuhide

    2004-01-01

    Slush hydrogen is a two-phase solid-liquid cryogenic fluid consisting of solid hydrogen particles in liquid hydrogen. Compared to liquid hydrogen, the density is about 16% greater at a solid mass ratio (solid fraction) of 50%, and the cryogenic heat capacity (enthalpy) is about 18% higher. Various applications are anticipated, including fuel for reusable space shuttles, coolant for cold neutron generation, as well as the transport and storage of hydrogen as a clean energy source. At a solid fraction of within 50%, piped transport can be conducted in the same way as for normal fluids. This paper reports on the slush hydrogen technology in terms of the measurement of the density and the mass flow rate.

  8. Precision top-quark mass measurement at CDF.

    PubMed

    Aaltonen, T; Alvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Appel, J A; Arisawa, T; Artikov, A; Asaadi, J; Ashmanskas, W; Auerbach, B; Aurisano, A; Azfar, F; Badgett, W; Bae, T; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartos, P; Bauce, M; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Bisello, D; Bizjak, I; Bland, K R; Blumenfeld, B; Bocci, A; Bodek, A; Bortoletto, D; Boudreau, J; Boveia, A; Brigliadori, L; Bromberg, C; Brucken, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Calamba, A; Calancha, C; Camarda, S; Campanelli, M; Campbell, M; Canelli, F; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chung, W H; Chung, Y S; Ciocci, M A; Clark, A; Clarke, C; Compostella, G; Convery, M E; Conway, J; Corbo, M; Cordelli, M; Cox, C A; Cox, D J; Crescioli, F; Cuevas, J; Culbertson, R; Dagenhart, D; d'Ascenzo, N; Datta, M; de Barbaro, P; Dell'Orso, M; Demortier, L; Deninno, M; Devoto, F; d'Errico, M; Di Canto, A; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Dorigo, M; Dorigo, T; Ebina, K; Elagin, A; Eppig, A; Erbacher, R; Errede, S; Ershaidat, N; Eusebi, R; Farrington, S; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Forrest, R; Frank, M J; Franklin, M; Freeman, J C; Funakoshi, Y; Furic, I; Gallinaro, M; Garcia, J E; Garfinkel, A F; Garosi, P; Gerberich, H; Gerchtein, E; Giagu, S; Giakoumopoulou, V; Giannetti, P; Gibson, K; Ginsburg, C M; Giokaris, N; Giromini, P; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldin, D; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Grinstein, S; Grosso-Pilcher, C; Group, R C; Guimaraes da Costa, J; Hahn, S R; Halkiadakis, E; Hamaguchi, A; Han, J Y; Happacher, F; Hara, K; Hare, D; Hare, M; Harr, R F; Hatakeyama, K; Hays, C; Heck, M; Heinrich, J; Herndon, M; Hewamanage, S; Hocker, A; Hopkins, W; Horn, D; Hou, S; Hughes, R E; Hurwitz, M; Husemann, U; Hussain, N; Hussein, M; Huston, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kamon, T; Karchin, P E; Kasmi, A; Kato, Y; Ketchum, W; Keung, J; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kim, Y J; Kimura, N; Kirby, M; Klimenko, S; Knoepfel, K; Kondo, K; Kong, D J; Konigsberg, J; Kotwal, A V; Kreps, M; Kroll, J; Krop, D; Kruse, M; Krutelyov, V; Kuhr, T; Kurata, M; Kwang, S; Laasanen, A T; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; LeCompte, T; Lee, E; Lee, H S; Lee, J S; Lee, S W; Leo, S; Leone, S; Lewis, J D; Limosani, A; Lin, C-J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, C; Liu, H; Liu, Q; Liu, T; Lockwitz, S; Loginov, A; Lucchesi, D; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lys, J; Lysak, R; Madrak, R; Maeshima, K; Maestro, P; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, C; Martínez, M; Mastrandrea, P; Matera, K; Mattson, M E; Mazzacane, A; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Mesropian, C; Miao, T; Mietlicki, D; Mitra, A; Miyake, H; Moed, S; Moggi, N; Mondragon, M N; Moon, C S; Moore, R; Morello, M J; Morlock, J; Movilla Fernandez, P; Mukherjee, A; Muller, Th; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Naganoma, J; Nakano, I; Napier, A; Nett, J; Neu, C; Neubauer, M S; Nielsen, J; Nodulman, L; Noh, S Y; Norniella, O; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Ortolan, L; Pagan Griso, S; Pagliarone, C; Palencia, E; Papadimitriou, V; Paramonov, A A; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Pianori, E; Pilot, J; Pitts, K; Plager, C; Pondrom, L; Poprocki, S; Potamianos, K; Prokoshin, F; Pranko, A; Ptohos, F; Punzi, G; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Renton, P; Rescigno, M; Riddick, T; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rodriguez, T; Rogers, E; Rolli, S; Roser, R; Ruffini, F; Ruiz, A; Russ, J; Rusu, V; Safonov, A; Sakumoto, W K; Sakurai, Y; Santi, L; Sato, K; Saveliev, V; Savoy-Navarro, A; Schlabach, P; Schmidt, A; Schmidt, E E; Schwarz, T; Scodellaro, L; Scribano, A; Scuri, F; Seidel, S; Seiya, Y; Semenov, A; Sforza, F; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shochet, M; Shreyber-Tecker, I; Simonenko, A; Sinervo, P; Sliwa, K; Smith, J R; Snider, F D; Soha, A; Sorin, V; Song, H; Squillacioti, P; Stancari, M; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Strycker, G L; Sudo, Y; Sukhanov, A; Suslov, I; Takemasa, K; Takeuchi, Y; Tang, J; Tecchio, M; Teng, P K; Thom, J; Thome, J; Thompson, G A; Thomson, E; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Trovato, M; Ukegawa, F; Uozumi, S; Varganov, A; Vázquez, F; Velev, G; Vellidis, C; Vidal, M; Vila, I; Vilar, R; Vizán, J; Vogel, M; Volpi, G; Wagner, P; Wagner, R L; Wakisaka, T; Wallny, R; Wang, S M; Warburton, A; Waters, D; Wester, W C; Whiteson, D; Wicklund, A B; Wicklund, E; Wilbur, S; Wick, F; Williams, H H; Wilson, J S; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, H; Wright, T; Wu, X; Wu, Z; Yamamoto, K; Yamato, D; Yang, T; Yang, U K; Yang, Y C; Yao, W-M; Yeh, G P; Yi, K; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanetti, A; Zeng, Y; Zhou, C; Zucchelli, S

    2012-10-12

    We present a precision measurement of the top-quark mass using the full sample of Tevatron √s = 1.96 TeV proton-antiproton collisions collected by the CDF II detector, corresponding to an integrated luminosity of 8.7 fb(-1). Using a sample of tt¯ candidate events decaying into the lepton+jets channel, we obtain distributions of the top-quark masses and the invariant mass of two jets from the W boson decays from data. We then compare these distributions to templates derived from signal and background samples to extract the top-quark mass and the energy scale of the calorimeter jets with in situ calibration. The likelihood fit of the templates from signal and background events to the data yields the single most-precise measurement of the top-quark mass, M(top)=172.85±0.71(stat)±0.85(syst) GeV/c(2).

  9. Measuring neutrino masses with a future galaxy survey

    SciTech Connect

    Hamann, Jan; Hannestad, Steen; Wong, Yvonne Y.Y. E-mail: sth@phys.au.dk

    2012-11-01

    We perform a detailed forecast on how well a EUCLID-like photometric galaxy and cosmic shear survey will be able to constrain the absolute neutrino mass scale. Adopting conservative assumptions about the survey specifications and assuming complete ignorance of the galaxy bias, we estimate that the minimum mass sum of Σm{sub ν} ≅ 0.06 eV in the normal hierarchy can be detected at 1.5σ to 2.5σ significance, depending on the model complexity, using a combination of galaxy and cosmic shear power spectrum measurements in conjunction with CMB temperature and polarisation observations from PLANCK. With better knowledge of the galaxy bias, the significance of the detection could potentially reach 5.4σ. Interestingly, neither PLANCK+shear nor PLANCK+galaxy alone can achieve this level of sensitivity; it is the combined effect of galaxy and cosmic shear power spectrum measurements that breaks the persistent degeneracies between the neutrino mass, the physical matter density, and the Hubble parameter. Notwithstanding this remarkable sensitivity to Σm{sub ν}, EUCLID-like shear and galaxy data will not be sensitive to the exact mass spectrum of the neutrino sector; no significant bias ( < 1σ) in the parameter estimation is induced by fitting inaccurate models of the neutrino mass splittings to the mock data, nor does the goodness-of-fit of these models suffer any significant degradation relative to the true one (Δχ{sub eff}{sup 2} < 1)

  10. Precision Top-Quark Mass Measurements at CDF

    SciTech Connect

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Arisawa, T.; Artikov, A.; /Dubna, JINR /Texas A-M

    2012-07-01

    We present a precision measurement of the top-quark mass using the full sample of Tevatron {radical}s = 1.96 TeV proton-antiproton collisions collected by the CDF II detector, corresponding to an integrated luminosity of 8.7 fb{sup -1}. Using a sample of t{bar t} candidate events decaying into the lepton+jets channel, we obtain distributions of the top-quark masses and the invariant mass of two jets from the W boson decays from data. We then compare these distributions to templates derived from signal and background samples to extract the top-quark mass and the energy scale of the calorimeter jets with in situ calibration. The likelihood fit of the templates from signal and background events to the data yields the single most-precise measurement of the top-quark mass, mtop = 172.85 {+-} 0.71 (stat) {+-} 0.85 (syst) GeV/c{sup 2}.

  11. Assimilating aircraft-based measurements to improve forecast accuracy of volcanic ash transport

    NASA Astrophysics Data System (ADS)

    Fu, G.; Lin, H. X.; Heemink, A. W.; Segers, A. J.; Lu, S.; Palsson, T.

    2015-08-01

    The 2010 Eyjafjallajökull volcano eruption had serious consequences to civil aviation. This has initiated a lot of research on volcanic ash transport forecast in recent years. For forecasting the volcanic ash transport after eruption onset, a volcanic ash transport and diffusion model (VATDM) needs to be run with Eruption Source Parameters (ESP) such as plume height and mass eruption rate as input, and with data assimilation techniques to continuously improve the initial conditions of the forecast. Reliable and accurate ash measurements are crucial for providing a successful ash clouds advice. In this paper, simulated aircraft-based measurements, as one type of volcanic ash measurements, will be assimilated into a transport model to identify the potential benefit of this kind of observations in an assimilation system. The results show assimilating aircraft-based measurements can significantly improve the state of ash clouds, and further providing an improved forecast as aviation advice. We also show that for advice of aeroplane flying level, aircraft-based measurements should be preferably taken from this level to obtain the best performance on it. Furthermore it is shown that in order to make an acceptable advice for aviation decision makers, accurate knowledge about uncertainties of ESPs and measurements is of great importance.

  12. Pendulum mass affects the measurement of articular friction coefficient.

    PubMed

    Akelman, Matthew R; Teeple, Erin; Machan, Jason T; Crisco, Joseph J; Jay, Gregory D; Fleming, Braden C

    2013-02-01

    Friction measurements of articular cartilage are important to determine the relative tribologic contributions made by synovial fluid or cartilage, and to assess the efficacy of therapies for preventing the development of post-traumatic osteoarthritis. Stanton's equation is the most frequently used formula for estimating the whole joint friction coefficient (μ) of an articular pendulum, and assumes pendulum energy loss through a mass-independent mechanism. This study examines if articular pendulum energy loss is indeed mass independent, and compares Stanton's model to an alternative model, which incorporates viscous damping, for calculating μ. Ten loads (25-100% body weight) were applied in a random order to an articular pendulum using the knees of adult male Hartley guinea pigs (n=4) as the fulcrum. Motion of the decaying pendulum was recorded and μ was estimated using two models: Stanton's equation, and an exponential decay function incorporating a viscous damping coefficient. μ estimates decreased as mass increased for both models. Exponential decay model fit error values were 82% less than the Stanton model. These results indicate that μ decreases with increasing mass, and that an exponential decay model provides a better fit for articular pendulum data at all mass values. In conclusion, inter-study comparisons of articular pendulum μ values should not be made without recognizing the loads used, as μ values are mass dependent. PMID:23122223

  13. Dynamical Mass Measurements of Contaminated Galaxy Clusters Using Machine Learning

    NASA Astrophysics Data System (ADS)

    Ntampaka, M.; Trac, H.; Sutherland, D. J.; Fromenteau, S.; Póczos, B.; Schneider, J.

    2016-11-01

    We study dynamical mass measurements of galaxy clusters contaminated by interlopers and show that a modern machine learning algorithm can predict masses by better than a factor of two compared to a standard scaling relation approach. We create two mock catalogs from Multidark’s publicly available N-body MDPL1 simulation, one with perfect galaxy cluster membership information and the other where a simple cylindrical cut around the cluster center allows interlopers to contaminate the clusters. In the standard approach, we use a power-law scaling relation to infer cluster mass from galaxy line-of-sight (LOS) velocity dispersion. Assuming perfect membership knowledge, this unrealistic case produces a wide fractional mass error distribution, with a width of {{Δ }}ε ≈ 0.87. Interlopers introduce additional scatter, significantly widening the error distribution further ({{Δ }}ε ≈ 2.13). We employ the support distribution machine (SDM) class of algorithms to learn from distributions of data to predict single values. Applied to distributions of galaxy observables such as LOS velocity and projected distance from the cluster center, SDM yields better than a factor-of-two improvement ({{Δ }}ε ≈ 0.67) for the contaminated case. Remarkably, SDM applied to contaminated clusters is better able to recover masses than even the scaling relation approach applied to uncontaminated clusters. We show that the SDM method more accurately reproduces the cluster mass function, making it a valuable tool for employing cluster observations to evaluate cosmological models.

  14. Pendulum mass affects the measurement of articular friction coefficient.

    PubMed

    Akelman, Matthew R; Teeple, Erin; Machan, Jason T; Crisco, Joseph J; Jay, Gregory D; Fleming, Braden C

    2013-02-01

    Friction measurements of articular cartilage are important to determine the relative tribologic contributions made by synovial fluid or cartilage, and to assess the efficacy of therapies for preventing the development of post-traumatic osteoarthritis. Stanton's equation is the most frequently used formula for estimating the whole joint friction coefficient (μ) of an articular pendulum, and assumes pendulum energy loss through a mass-independent mechanism. This study examines if articular pendulum energy loss is indeed mass independent, and compares Stanton's model to an alternative model, which incorporates viscous damping, for calculating μ. Ten loads (25-100% body weight) were applied in a random order to an articular pendulum using the knees of adult male Hartley guinea pigs (n=4) as the fulcrum. Motion of the decaying pendulum was recorded and μ was estimated using two models: Stanton's equation, and an exponential decay function incorporating a viscous damping coefficient. μ estimates decreased as mass increased for both models. Exponential decay model fit error values were 82% less than the Stanton model. These results indicate that μ decreases with increasing mass, and that an exponential decay model provides a better fit for articular pendulum data at all mass values. In conclusion, inter-study comparisons of articular pendulum μ values should not be made without recognizing the loads used, as μ values are mass dependent.

  15. CAN THE MASSES OF ISOLATED PLANETARY-MASS GRAVITATIONAL LENSES BE MEASURED BY TERRESTRIAL PARALLAX?

    SciTech Connect

    Freeman, M.; Botzler, C. S.; Bray, J. C.; Cherrie, J. M.; Rattenbury, N. J.; Philpott, L. C.; Abe, F.; Muraki, Y.; Albrow, M. D.; Bennett, D. P.; Bond, I. A.; Christie, G. W.; Natusch, T.; Dionnet, Z.; Gould, A.; Han, C.; Heyrovský, D.; McCormick, J. M.; Skowron, J.; and others

    2015-02-01

    Recently Sumi et al. reported evidence for a large population of planetary-mass objects (PMOs) that are either unbound or orbit host stars in orbits ≥10 AU. Their result was deduced from the statistical distribution of durations of gravitational microlensing events observed by the MOA collaboration during 2006 and 2007. Here we study the feasibility of measuring the mass of an individual PMO through microlensing by examining a particular event, MOA-2011-BLG-274. This event was unusual as the duration was short, the magnification high, the source-size effect large, and the angular Einstein radius small. Also, it was intensively monitored from widely separated locations under clear skies at low air masses. Choi et al. concluded that the lens of the event may have been a PMO but they did not attempt a measurement of its mass. We report here a re-analysis of the event using re-reduced data. We confirm the results of Choi et al. and attempt a measurement of the mass and distance of the lens using the terrestrial parallax effect. Evidence for terrestrial parallax is found at a 3σ level of confidence. The best fit to the data yields the mass and distance of the lens as 0.80 ± 0.30 M {sub J} and 0.80 ± 0.25 kpc respectively. We exclude a host star to the lens out to a separation ∼40 AU. Drawing on our analysis of MOA-2011-BLG-274 we propose observational strategies for future microlensing surveys to yield sharper results on PMOs including those down to super-Earth mass.

  16. Measurements of the tau Mass and Mass Difference of the tau^+ and tau^- at BABAR

    SciTech Connect

    Aubert, B.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2009-10-30

    The authors present the result of a precision measurement of the mass of the {tau} lepton, M{sub {tau}}, based on 423 fb{sup -1} of data recorded at the {Upsilon}(4S) resonance with the BABAR detector. Using a pseudomass endpoint method, they determine the mass to be 1776.68 {+-} 0.12(stat) {+-} 0.41(syst) MeV. They also measure the mass difference between the {tau}{sup +} and {tau}{sup -}, and obtain (M{sub {tau}{sup +}} - M{sub {tau}{sup -}})/M{sub AVG}{sup {tau}} = (-3.4 {+-} 1.3(stat) {+-} 0.3(syst)) x 10{sup -4}, where M{sub AVG}{sup {tau}} is the average value of M{sub {tau}{sup +}} and M{sub {tau}{sup -}}.

  17. Mass measurement errors caused by 'local" frequency perturbations in FTICR mass spectrometry.

    PubMed

    Masselon, Christophe; Tolmachev, Aleksey V; Anderson, Gordon A; Harkewicz, Richard; Smith, Richard D

    2002-01-01

    One of the key qualities of mass spectrometric measurements for biomolecules is the mass measurement accuracy (MMA) obtained. FTICR presently provides the highest MMA over a broad m/z range. However, due to space charge effects, the achievable MMA crucially depends on the number of ions trapped in the ICR cell for a measurement. Thus, beyond some point, as the effective sensitivity and dynamic range of a measurement increase, MMA tends to decrease. While analyzing deviations from the commonly used calibration law in FTICR we have found systematic errors which are not accounted for by a "global" space charge correction approach. The analysis of these errors and their dependence on charge population and post-excite radius have led us to conclude that each ion cloud experiences a different interaction with other ion clouds. We propose a novel calibration function which is shown to provide an improvement in MMA for all the spectra studied.

  18. Mass Transport and Turbulence in Gravitationally Unstable Disk Galaxies. II: The Effects of Star Formation Feedback

    NASA Astrophysics Data System (ADS)

    Goldbaum, Nathan J.; Krumholz, Mark R.; Forbes, John C.

    2016-08-01

    Self-gravity and stellar feedback are capable of driving turbulence and transporting mass and angular momentum in disk galaxies, but the balance between them is not well understood. In the previous paper in this series, we showed that gravity alone can drive turbulence in galactic disks, regulate their Toomre Q parameters to ˜1, and transport mass inwards at a rate sufficient to fuel star formation in the centers of present-day galaxies. In this paper we extend our models to include the effects of star formation feedback. We show that feedback suppresses galaxies’ star formation rates by a factor of ˜5 and leads to the formation of a multi-phase atomic and molecular interstellar medium. Both the star formation rate and the phase balance produced in our simulations agree well with observations of nearby spirals. After our galaxies reach steady state, we find that the inclusion of feedback actually lowers the gas velocity dispersion slightly compared to the case of pure self-gravity, and also slightly reduces the rate of inward mass transport. Nevertheless, we find that, even with feedback included, our galactic disks self-regulate to Q ˜ 1, and transport mass inwards at a rate sufficient to supply a substantial fraction of the inner disk star formation. We argue that gravitational instability is therefore likely to be the dominant source of turbulence and transport in galactic disks, and that it is responsible for fueling star formation in the inner parts of galactic disks over cosmological times.

  19. Maximum Mass of Strange Stars and Pulsars with the Most Accurately Measured Masses

    NASA Astrophysics Data System (ADS)

    Vartanyan, Yu. L.; Grigoryan, A. K.; Shahinyan, H. A.

    2015-06-01

    Strange quark matter (SQM) is studied using a bag model in which the transition to the SQM state takes place at energy densities of no more than twice the density in atomic nuclei. Thus, low mass neutron stars with a configuration consisting of SQM form a single family on a plot of the mass M of equilibrium superdense configurations as a function of central energy density ρ c (the M(ρ c ) curve). The bag model considered here depends on three constants: the vacuum pressure B, the quark-gluon interaction constant α c , and the strange quark mass m s . Sets of values of these constants are determined, which if used in the equation of state for SQM yield a maximal mass M max of the equilibrium quark configurations which exceeds the recently accurately determined mass of 2.01 M ⊙ for the binary radio pulsar PSR J0348+0432. The mass, radius, total baryon number, and red shift from the surface of the strange star are calculated for these configurations as a function of central energy density ρ c . The values of these integrated parameters are also calculated for each series with M max > 2.01 M ⊙ for superdense configurations with masses of 2.01, 1.97, and 1.44 solar masses, which have been determined with great accuracy from observations. It turns out that, according to the resulting equations of state, all of the three pulsars with the most accurately measured masses, may be possible candidate strange stars.

  20. Lensing measurements of the mass distribution in SDSS voids

    NASA Astrophysics Data System (ADS)

    Clampitt, Joseph; Jain, Bhuvnesh

    2015-12-01

    We measure weak lensing mass profiles of voids from a volume-limited sample of SDSS Luminous Red Galaxies (LRGs). We find voids using an algorithm designed to maximize the lensing signal by dividing the survey volume into 2D slices, and then finding holes in this 2D distribution of LRGs. We perform a stacked shear measurement on about 20 000 voids with radii between 15 and 55 Mpc h-1, and redshifts between 0.16 and 0.37. We measure the characteristic radial shear signal of voids with a signal to noise of 7. The mass profile corresponds to a fractional underdensity of about -0.4 inside the void radius and a slow approach to the mean density indicating a partially compensated void structure. We compare our measured shape and amplitude with the predictions of Krause et al. Voids in the galaxy distribution have been extensively modelled using simulations and measured in the SDSS. We discuss how the addition of void mass profiles can enable studies of galaxy formation and cosmology.

  1. Mass Measurements of Isolated Objects from Space-based Microlensing

    NASA Astrophysics Data System (ADS)

    Zhu, Wei; Calchi Novati, S.; Gould, A.; Udalski, A.; Han, C.; Shvartzvald, Y.; Ranc, C.; Jørgensen, U. G.; Poleski, R.; Bozza, V.; Beichman, C.; Bryden, G.; Carey, S.; Gaudi, B. S.; Henderson, C. B.; Pogge, R. W.; Porritt, I.; Wibking, B.; Yee, J. C.; SPITZER Team; Pawlak, M.; Szymański, M. K.; Skowron, J.; Mróz, P.; Kozłowski, S.; Wyrzykowski, Ł.; Pietrukowicz, P.; Pietrzyński, G.; Soszyński, I.; Ulaczyk, K.; OGLE Group; Choi, J.-Y.; Park, H.; Jung, Y. K.; Shin, I.-G.; Albrow, M. D.; Park, B.-G.; Kim, S.-L.; Lee, C.-U.; Cha, S.-M.; Kim, D.-J.; Lee, Y.; KMTNET Group; Friedmann, M.; Kaspi, S.; Maoz, D.; WISE Group; Hundertmark, M.; Street, R. A.; Tsapras, Y.; Bramich, D. M.; Cassan, A.; Dominik, M.; Bachelet, E.; Dong, Subo; Figuera Jaimes, R.; Horne, K.; Mao, S.; Menzies, J.; Schmidt, R.; Snodgrass, C.; Steele, I. A.; Wambsganss, J.; RoboNeT Team; Skottfelt, J.; Andersen, M. I.; Burgdorf, M. J.; Ciceri, S.; D'Ago, G.; Evans, D. F.; Gu, S.-H.; Hinse, T. C.; Kerins, E.; Korhonen, H.; Kuffmeier, M.; Mancini, L.; Peixinho, N.; Popovas, A.; Rabus, M.; Rahvar, S.; Tronsgaard, R.; Scarpetta, G.; Southworth, J.; Surdej, J.; von Essen, C.; Wang, Y.-B.; Wertz, O.; MiNDSTEP Group

    2016-07-01

    We report on the mass and distance measurements of two single-lens events from the 2015 Spitzer microlensing campaign. With both finite-source effect and microlens parallax measurements, we find that the lens of OGLE-2015-BLG-1268 is very likely a brown dwarf (BD). Assuming that the source star lies behind the same amount of dust as the Bulge red clump, we find the lens is a 45 ± 7 {M}{{J}} BD at 5.9 ± 1.0 kpc. The lens of of the second event, OGLE-2015-BLG-0763, is a 0.50 ± 0.04 {M}⊙ star at 6.9 ± 1.0 kpc. We show that the probability to definitively measure the mass of isolated microlenses is dramatically increased once simultaneous ground- and space-based observations are conducted.

  2. Measurement of the Top Quark Mass at CDF II

    SciTech Connect

    Kovalev, Andrew N

    2003-11-01

    The authors describe a measurement of the top quark mass using events with two charged leptons collected by the CDF II Detector from p{bar p} collisions with {radical}s = 1.96 TeV at the Fermilab Tevatron. The posterior probability distribution of the top quark pole mass is calculated using the differential cross-section for the t{bar t} production and decay expressed with respect to observed leptons and jets momenta. The presence of background events in the collected sample is modeled using calculations of the differential cross-sections for major background processes. This measurement represents the first application of this method to events with two charged leptons. In a data sample with integrated luminosity of 340 pb{sup -1}, they observe 33 candidate events and measure M{sub top} = 165.2 {+-} 61.{sub stat} {+-} 3.4{sub syst} GeV/c{sup 2}.

  3. Mass Measurements of Isolated Objects from Space-based Microlensing

    NASA Astrophysics Data System (ADS)

    Zhu, Wei; Calchi Novati, S.; Gould, A.; Udalski, A.; Han, C.; Shvartzvald, Y.; Ranc, C.; Jørgensen, U. G.; Poleski, R.; Bozza, V.; Beichman, C.; Bryden, G.; Carey, S.; Gaudi, B. S.; Henderson, C. B.; Pogge, R. W.; Porritt, I.; Wibking, B.; Yee, J. C.; SPITZER Team; Pawlak, M.; Szymański, M. K.; Skowron, J.; Mróz, P.; Kozłowski, S.; Wyrzykowski, Ł.; Pietrukowicz, P.; Pietrzyński, G.; Soszyński, I.; Ulaczyk, K.; OGLE Group; Choi, J.-Y.; Park, H.; Jung, Y. K.; Shin, I.-G.; Albrow, M. D.; Park, B.-G.; Kim, S.-L.; Lee, C.-U.; Cha, S.-M.; Kim, D.-J.; Lee, Y.; KMTNET Group; Friedmann, M.; Kaspi, S.; Maoz, D.; WISE Group; Hundertmark, M.; Street, R. A.; Tsapras, Y.; Bramich, D. M.; Cassan, A.; Dominik, M.; Bachelet, E.; Dong, Subo; Figuera Jaimes, R.; Horne, K.; Mao, S.; Menzies, J.; Schmidt, R.; Snodgrass, C.; Steele, I. A.; Wambsganss, J.; RoboNeT Team; Skottfelt, J.; Andersen, M. I.; Burgdorf, M. J.; Ciceri, S.; D'Ago, G.; Evans, D. F.; Gu, S.-H.; Hinse, T. C.; Kerins, E.; Korhonen, H.; Kuffmeier, M.; Mancini, L.; Peixinho, N.; Popovas, A.; Rabus, M.; Rahvar, S.; Tronsgaard, R.; Scarpetta, G.; Southworth, J.; Surdej, J.; von Essen, C.; Wang, Y.-B.; Wertz, O.; MiNDSTEP Group

    2016-07-01

    We report on the mass and distance measurements of two single-lens events from the 2015 Spitzer microlensing campaign. With both finite-source effect and microlens parallax measurements, we find that the lens of OGLE-2015-BLG-1268 is very likely a brown dwarf (BD). Assuming that the source star lies behind the same amount of dust as the Bulge red clump, we find the lens is a 45 ± 7 {M}{{J}} BD at 5.9 ± 1.0 kpc. The lens of of the second event, OGLE-2015-BLG-0763, is a 0.50 ± 0.04 {M}ȯ star at 6.9 ± 1.0 kpc. We show that the probability to definitively measure the mass of isolated microlenses is dramatically increased once simultaneous ground- and space-based observations are conducted.

  4. Measuring Black Hole Masses in Quasars: The Hows and Whys

    NASA Astrophysics Data System (ADS)

    Denney, Kelly D.

    2015-08-01

    The co-evolution of galaxies and the supermassive black holes that reside in their centers, combined with the overwhelming success of cosmological models to describe the observed universe through hierarchical growth of structure, suggests that these black holes are necessary building blocks of galaxies. Studying the demographics and growth rates of black holes and the impact of black hole accretion and feedback on the host galaxy and circumgalactic medium are imperative for our understanding of galaxy evolution. The only way to probe these properties at high redshift, where the bulk of stellar-mass assembly and black hole growth takes place, is through studies of quasars - galaxies containing supermassive black holes that are actively accreting. I will discuss recent work to improve the reliability of high redshift quasar black hole mass measurements, and thereby growth rates, and the current best practices for making these measurements. In addition, I will discuss how the intrinsic structure of the quasar itself, including the presence of AGN winds and outflows, is correlated with the data quality of quasar spectra to impact the reliability of quasar black hole masses. Finally, I will briefly discuss international efforts, of both collaborations and resources, toward making direct black hole mass measurements in high redshift quasars.

  5. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    NASA Astrophysics Data System (ADS)

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, J.; Koleška, M.; Voljanskij, A.

    2015-11-01

    Mercury is an essential component of fluorescent lamps. Not all fluorescent lamps are recycled, resulting in contamination of the environment with toxic mercury, making measurement of the mercury mass used in fluorescent lamps important. Mercury mass measurement of lamps via instrumental neutron activation analysis (NAA) was tested under various conditions in the LVR-15 research reactor. Fluorescent lamps were irradiated in different positions in vertical irradiation channels and a horizontal channel in neutron fields with total fluence rates from 3×108 cm-2 s-1 to 1014 cm-2 s-1. The 202Hg(n,γ)203Hg nuclear reaction was used for mercury mass evaluation. Activities of 203Hg and others induced radionuclides were measured via gamma spectrometry with an HPGe detector at various times after irradiation. Standards containing an Hg2Cl2 compound were used to determine mercury mass. Problems arise from the presence of elements with a large effective cross section in luminescent material (europium, antimony and gadolinium) and glass (boron). The paper describes optimization of the NAA procedure in the LVR-15 research reactor with particular attention to influence of neutron self-absorption in fluorescent lamps.

  6. Neutrino Mass Measurement Using a Directed Mono-Energetic Beam

    NASA Astrophysics Data System (ADS)

    Tsifrinovich, Vladimir; Folan, Lorcan

    2015-04-01

    It was shown that a directed mono-energetic neutrino beam can be generated by electron capture beta-decay in a sample with a strong hyperfine field at the radioactive nuclei. We study the conditions required to measure the neutrino rest mass using the recoil force produced by a directed neutrino beam. We consider the displacement of an atomic force microscope cantilever due to such a recoil force. We find the change in the cantilever displacement associated with the non-zero neutrino mass, as a function of nuclear half-life T1 / 2, cantilever spring constant, and temperature. We consider the opportunity to increase the sensitivity of the neutrino mass measurement using averaging of the measurement signal. We show that the optimal time for the signal accumulation is, approximately, 1.8T1 / 2. We compute the optimal signal-to-noise ratio for 119Sb nuclei decaying to 119Sn with a decrease in the nuclear spin from I = 5/2 to I = 3/2, and T1 / 2 = 38.2 hours. Finally, we present the parameters values required for detection of sub-eV neutrino rest mass, and estimate the angular distribution of neutrino radiation as a function of temperature.

  7. Measurement of the top quark mass at D0

    SciTech Connect

    Protopopescu, S.; D0 Collaboration

    1996-12-31

    The mass of the top quark is measured using a sample of 93 lepton + 4 or more jets events collected with the D0 detector at the FNAL Tevatron collider. The authors find the top quark mass is 169 {+-} 8(stat.) {+-} 8(syst.) GeV/c{sup 2}. The analysis assumes that top quarks are produced as t{anti t} pairs that decay to W bosons and b quarks. The final states result when one W decays to e{nu} or {mu}{nu} and the other W to q{anti q}. More than four jets may be present because of final and initial state radiation.

  8. Measuring the W boson mass at the Tevatron

    SciTech Connect

    Sanders, M.P.; /Munich U.

    2010-09-01

    The measurement of the mass of the W boson is one of the prime goals of the Tevatron experiments. In this contribution, a review is given of the most recent determinations of the W boson mass (m{sub W}) at the Tevatron. The combined Tevatron result, m{sub W} = 80.420 {+-} 0.031 GeV, is now more precise than the combined LEP result, leading to a world average value of m{sub W} = 80.399 {+-} 0.023 GeV.

  9. Measurement of the radiative transport properties of reticulated alumina foams

    SciTech Connect

    Hale, M.J.; Bohn, M.S.

    1992-12-01

    This paper presents a method for determining radiative transport properties of reticulated materials. The method has both experimental and analytical components. A polar nephelometer is used to measure the scattering profile of a sample of the reticulated material. The results of a Monte Carlo simulation of the experiment are then combined with the experimental results to give the scatter albedo and extinction coefficient. This paper presents the results of using this method to determine the radiative transport properties of four different porosities (10, 20, 30, 65 pores per inch) of cylindrical reticulated alumina samples ranging in thickness form 0.5 inches to 2. 5 inches.

  10. Measuring doubly 13C-substituted ethane by mass spectrometry

    NASA Astrophysics Data System (ADS)

    Clog, M.; Ling, C.; Eiler, J. M.

    2012-12-01

    Ethane (C2H6) is present in non-negligible amounts in most natural gas reservoirs and is used to produce ethylene for petrochemical industries. It is one of the by-products of lipid metabolism and is the arguably simplest molecule that can manifest multiple 13C substitutions. There are several plausible controls on the relative abundances of 13C2H6 in natural gases: thermodynamically controlled homogeneous isotope exchange reactions analogous to those behind carbonate clumped isotope thermometry; inheritance from larger biomolecules that under thermal degradation to produce natural gas; mixing of natural gases that differ markedly in bulk isotopic composition; or combinations of these and/or other, less expected fractionations. There is little basis for predicting which of these will dominate in natural samples. Here, we focus on an analytical techniques that will provide the avenue for exploring these phenomena. The method is based on high-resolution gas source isotope ratio mass spectrometry, using the Thermo 253-Ultra (a new prototype mass spectrometer). This instrument achieves the mass resolution (M/Δ M) up to 27,000, permitting separation of the isobaric interferences of potential contaminants and isotopologues of an analtye or its fragments which share a cardinal mass. We present techniques to analyze several isotopologues of molecular and fragment ions of C2H6. The critical isobaric separations for our purposes include: discrimination of 13C2H6 from 13C12CDH5 at mass 32 and separation of the 13CH3 fragment from 12CH4 at mass 16, both requiring at least a mass resolution of 20000 to make an adequate measurement. Other obvious interferences are either cleanly separated (e.g., O2, O) or accounted for by peak-stripping (CH3OH on mass 32 and NH2 on mass 16). We focus on a set of measurements which constrain: the doubly-substituted isotopologue, 13C2H6, and the 13CH3/12CH3 ratio of the methyl fragment, which constrains the bulk δ 13C. Similar methods can be

  11. Precision measurements of the top quark mass at the Tevatron

    SciTech Connect

    Whiteson, Daniel; /Pennsylvania U.

    2006-05-01

    We report precision measurements of the top quark mass using events collected by the D0 and CDF II detectors from p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron. Measurements are presented in multiple decay channels. In addition, we present a combination of the most precise measurements in each channel to date: M{sub top} = 172.5 {+-} 1.3{sub stat} {+-} 1.9{sub syst} GeV/c{sup 2}.

  12. Control System Upgrade for a Mass Property Measurement Facility

    NASA Technical Reports Server (NTRS)

    Chambers, William; Hinkle, R. Kenneth (Technical Monitor)

    2002-01-01

    The Mass Property Measurement Facility (MPMF) at the Goddard Space Flight Center has undergone modifications to ensure the safety of Flight Payloads and the measurement facility. The MPMF has been technically updated to improve reliability and increase the accuracy of the measurements. Modifications include the replacement of outdated electronics with a computer based software control system, the addition of a secondary gas supply in case of a catastrophic failure to the gas supply and a motor controlled emergency stopping feature instead of a hard stop.

  13. Mass transport properties of Pu/DT mixtures from orbital free molecular dynamics simulations

    SciTech Connect

    Kress, Joel David; Ticknor, Christopher; Collins, Lee A.

    2015-09-16

    Mass transport properties (shear viscosity and diffusion coefficients) for Pu/DT mixtures were calculated with Orbital Free Molecular Dynamics (OFMD). The results were fitted to simple functions of mass density (for ρ=10.4 to 62.4 g/cm3) and temperature (for T=100 up to 3,000 eV) for Pu/DT mixtures consisting of 100/0, 25/75, 50/50, and 75/25 by number.

  14. Dependence of Dynamic Modeling Accuracy on Sensor Measurements, Mass Properties, and Aircraft Geometry

    NASA Technical Reports Server (NTRS)

    Grauer, Jared A.; Morelli, Eugene A.

    2013-01-01

    The NASA Generic Transport Model (GTM) nonlinear simulation was used to investigate the effects of errors in sensor measurements, mass properties, and aircraft geometry on the accuracy of identified parameters in mathematical models describing the flight dynamics and determined from flight data. Measurements from a typical flight condition and system identification maneuver were systematically and progressively deteriorated by introducing noise, resolution errors, and bias errors. The data were then used to estimate nondimensional stability and control derivatives within a Monte Carlo simulation. Based on these results, recommendations are provided for maximum allowable errors in sensor measurements, mass properties, and aircraft geometry to achieve desired levels of dynamic modeling accuracy. Results using additional flight conditions and parameter estimation methods, as well as a nonlinear flight simulation of the General Dynamics F-16 aircraft, were compared with these recommendations

  15. Coupled effects of temperature and mass transport on the isotope fractionation of zinc during electroplating

    NASA Astrophysics Data System (ADS)

    Black, Jay R.; John, Seth G.; Kavner, Abby

    2014-01-01

    The isotopic composition of zinc metal electrodeposited on a rotating disc electrode from a Zn-citrate aqueous solution was investigated as a function of overpotential (electrochemical driving force), temperature, and rotation rate. Zn metal was measured to be isotopically light with respect to Zn+2 in solution, with observed fractionations varying from Δ66/64Znmetal-aqueous = -1.0‰ to -3.9‰. Fractionation varies continuously as a function of a dimensionless parameter described by the ratio of observed deposition rate to calculated mass-transport limiting rate, where larger fractionations are observed at lower deposition rates, lower temperature, and at faster electrode rotation rates. Thus, the large fractionation and its rate dependence is interpreted as a competition between the two kinetic processes with different effective activation energies: mass-transport-limited (diffusion limited) kinetics with a large activation energy, which creates small fractionations close to the predicted diffusive fractionation; and electrochemical deposition kinetics, with a smaller effective activation energy, which creates large fractionations at low deposition rates and high hydrodynamic fluxes of solute to the electrode. The results provide a framework for predicting isotope fractionation in processes controlled by two competing reactions with different kinetic isotope effects. Light isotopes are electroplated. In all cases light stable isotopes of the metals are preferentially electroplated, with mass-dependent behavior evident where three or more isotopes are measured. Fractionation is time-independent, meaning that the fractionation factor does not vary with the extent of reaction. In most of our experiments, we have controlled the extent of reaction such that only a small amount of metal is deposited from the stock solution, thus avoiding significant evolution of the reservoir composition. In such experiments, the observed isotope fractionation is constant as a

  16. Coping with model uncertainty in data assimilation using optimal mass transport

    NASA Astrophysics Data System (ADS)

    Ning, L.; Carli, F. P.; Ebtehaj, M.; Foufoula-Georgiou, E.; Georgiou, T.

    2013-12-01

    Most data assimilation methods address the problem of optimally combining model predictions with observations in the presence of zero-mean Gaussian random errors. However, in many hydro-meteorological applications uncertainty in model parameters and/or model structure often result in systematic errors (bias). Examples include the prediction of precipitation or land surface fluxes at the wrong location and/or timing due to a drift in the model, unknown initial conditions, or non-additive error amplification. Existing bias-aware data assimilation methods require characterization of the bias in terms of a well-defined set of parameters or removal of bias, which is not always feasible. Here we present a new variational data assimilation framework to cope with model bias in a non-parametric fashion via an appropriate 'regularization' of the state evolution dynamics. In the context of weak-constraint 4D-VAR, our method can be seen as enforcing a minimum nonlinear distance (regularization or correction) in the evolution of the state so as to reconcile measurements with errors in the model dynamics. While a quadratic functional is typically sufficient to quantify errors in measurements, errors in state evolution is most naturally quantified by a transportation metric (Wasserstein metric) originating in the theory of Optimal Mass Transport (OMT). The proposed framework allows the use of additional regularization functionals, such as the L1-norm regularization of the state in an appropriately chosen domain, as recently introduced by the authors for states that exhibit sparsity and non-Gaussian priors, such as precipitation and soil moisture. We demonstrate the performance of the proposed method using as an example the 1-D and 2-D advection diffusion equation with systematic errors in the velocity and diffusivity parameters. Extension to real world data assimilation settings is currently under way.

  17. Measurement of the top quark mass in the dilepton channel

    SciTech Connect

    Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Agelou, M.; Aguilo, E.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; /Buenos Aires U. /Rio de Janeiro, CBPF /Rio de Janeiro State U. /Sao Paulo, IFT /Alberta U. /Simon Fraser U. /York U., Canada /McGill U. /Hefei, CUST /Andes U., Bogota /Charles U.

    2006-09-01

    We present a measurement of the top quark mass in the dilepton channel based on approximately 370 pb{sup -1} of data collected by the D0 experiment during Run II of the Fermilab Tevatron collider. We employ two different methods to extract the top quark mass. We show that both methods yield consistent results using ensemble tests of events generated with the D0 Monte Carlo simulation. We combine the results from the two methods to obtain a top quark mass m{sub t} = 178.1 {+-} 8.2 GeV. The statistical uncertainty is 6.7 GeV and the systematic uncertainty is 4.8 GeV.

  18. Ultra-low Q values for neutrino mass measurements

    SciTech Connect

    Kopp, Joachim; Merle, Alexander; /Heidelberg, Max Planck Inst.

    2009-11-01

    We investigate weak nuclear decays with extremely small kinetic energy release (Q value) and thus extremely good sensitivity to the absolute neutrino mass scale. In particular, we consider decays into excited daughter states, and we show that partial ionization of the parent atom can help to tune Q values to << 1 keV. We discuss several candidate isotopes undergoing {beta}{sup {+-}}, bound state {beta}, or electron capture decay, and come to the conclusion that a neutrino mass measurement using low-Q decays might only be feasible if no ionization is required, and if future improvements in isotope production technology, nuclear mass spectroscopy, and atomic structure calculations are possible. Experiments using ions, however, are extremely challenging due to the large number of ions that must be stored. New precision data on nuclear excitation levels could help to identify further isotopes with low-Q decay modes and possibly less challenging requirements.

  19. Accelerator mass spectrometry for measurement of long-lived radioisotopes.

    PubMed

    Elmore, D; Phillips, F M

    1987-05-01

    Particle accelerators, such as those built for research in nuclear physics, can also be used together with magnetic and electrostatic mass analyzers to measure rare isotopes at very low abundance ratios. All molecular ions can be eliminated when accelerated to energies of millions of electron volts. Some atomic isobars can be eliminated with the use of negative ions; others can be separated at high energies by measuring their rate of energy loss in a detector. The long-lived radioisotopes (10)Be, (14)C,(26)A1, 36Cl, and (129)1 can now be measured in small natural samples having isotopic abundances in the range 10(-12) to 10(- 5) and as few as 10(5) atoms. In the past few years, research applications of accelerator mass spectrometry have been concentrated in the earth sciences (climatology, cosmochemistry, environmental chemistry, geochronology, glaciology, hydrology, igneous petrogenesis, minerals exploration, sedimentology, and volcanology), in anthropology and archeology (radiocarbon dating), and in physics (searches for exotic particles and measurement of halflives). In addition, accelerator mass spectrometry may become an important tool for the materials and biological sciences. PMID:17740475

  20. Accelerator mass spectrometry for measurement of long-lived radioisotopes.

    PubMed

    Elmore, D; Phillips, F M

    1987-05-01

    Particle accelerators, such as those built for research in nuclear physics, can also be used together with magnetic and electrostatic mass analyzers to measure rare isotopes at very low abundance ratios. All molecular ions can be eliminated when accelerated to energies of millions of electron volts. Some atomic isobars can be eliminated with the use of negative ions; others can be separated at high energies by measuring their rate of energy loss in a detector. The long-lived radioisotopes (10)Be, (14)C,(26)A1, 36Cl, and (129)1 can now be measured in small natural samples having isotopic abundances in the range 10(-12) to 10(- 5) and as few as 10(5) atoms. In the past few years, research applications of accelerator mass spectrometry have been concentrated in the earth sciences (climatology, cosmochemistry, environmental chemistry, geochronology, glaciology, hydrology, igneous petrogenesis, minerals exploration, sedimentology, and volcanology), in anthropology and archeology (radiocarbon dating), and in physics (searches for exotic particles and measurement of halflives). In addition, accelerator mass spectrometry may become an important tool for the materials and biological sciences.

  1. The water mass structure and transports in the Atlantic Subpolar Gyre

    NASA Astrophysics Data System (ADS)

    García-Ibáñez, Maribel I.; Pardo, Paula C.; Carracedo, Lidia I.; Mercier, Herlé; Lherminier, Pascale; Ríos, Aida F.; Pérez, Fiz F.

    2014-05-01

    The water mass structure, mixing and spreading in the North Atlantic Subpolar Gyre (SPG) were analyzed by means of an extended Optimum MultiParameter (eOMP) approach over the six repeats of the WOCE A25 hydrographic line located at the southern boundary of this gyre. The data includes the Fourex (4x) line taken in 1997 and the five repeat sections of the OVIDE line taken every other year from 2002 to 2010. We proposed 10 water masses, defined by their thermohaline properties (potential temperature and salinity), oxygen and nutrients (nitrate, phosphate and silicate), to resolve the water mass structure of the SPG. The eOMP enables to decompose the transports by water mass quantitatively. Our model provides water mass distributions that are able to reproduce the input data of potential temperature, salinity and silicate with r2>0.997 and of oxygen, nitrate and phosphate with r2>0.96. By combining the velocity field and the water mass structure across each section we provide the relative contribution of each water mass to the Meridional Overturning Circulation (MOC) and we evaluate the water mass transformation in the North Atlantic. The MOC upper limb during OVIDE (2002-2010) is constituted by the northward transports of the central waters (9.4 Sv; 1 Sv = 106 m3 s-1), the Subarctic Intermediate Water (SAIW, 2.8 Sv) and the Subpolar Mode Water (SPMW) of the Iceland Basin (2.1 Sv). The MOC lower limb is constituted by the southward transports of the Iceland-Scotland Overflow Water (ISOW, 2.9 Sv), the Denmark Strait Overflow Water (DSOW, 2.5 Sv), the Polar Intermediate Water (PIW, 0.8 Sv), the Labrador Sea Water (LSW, 3.6 Sv) and the SPMW of the Irminger Sea (4.7 Sv). These results contrast with those obtained for the 1997, cruise developed after a period of high NAO index. The greater MOC strength in 1997 resulted in greater northward transports of central waters (17.5 Sv), while the SAIW transports remained approximately unchanged. The increase of the northward

  2. Measurement uncertainties in quantifying aeolian mass flux: evidence from wind tunnel and field site data

    PubMed Central

    Keijsers, Joep G.S.; Maroulis, Jerry; Visser, Saskia M.

    2014-01-01

    Aeolian sediment traps are widely used to estimate the total volume of wind-driven sediment transport, but also to study the vertical mass distribution of a saltating sand cloud. The reliability of sediment flux estimations from such measurements are dependent upon the specific configuration of the measurement compartments and the analysis approach used. In this study, we analyse the uncertainty of these measurements by investigating the vertical cumulative distribution and relative sediment flux derived from both wind tunnel and field studies. Vertical flux data was examined using existing data in combination with a newly acquired dataset; comprising meteorological data and sediment fluxes from six different events, using three customized catchers at Ameland beaches in northern Netherlands. Fast-temporal data collected in a wind tunnel shows that the median transport height has a scattered pattern between impact and fluid threshold, that increases linearly with shear velocities above the fluid threshold. For finer sediment, a larger proportion was transported closer to the surface compared to coarser sediment fractions. It was also shown that errors originating from the distribution of sampling compartments, specifically the location of the lowest sediment trap relative to the surface, can be identified using the relative sediment flux. In the field, surface conditions such as surface moisture, surface crusts or frozen surfaces have a more pronounced but localized effect than shear velocity. Uncertainty in aeolian mass flux estimates can be reduced by placing multiple compartments in closer proximity to the surface. PMID:25071984

  3. Longterm Measurements of Bedload-Transport in alpine Catchments

    NASA Astrophysics Data System (ADS)

    Achleitner, Stefan; Kammerlander, Johannes; Eichner, Bernhard; Schöber, Johannes; Chiari, Michael

    2016-04-01

    In recent years the necessity of predicting the long-term behavior of sediment transport has increased. On the one hand, the effects of technical measures (e.g. retaining measures, hydropower, etc.) in the natural system are to be evaluated. On the other hand long term ecological studies that are strongly linked to the sediment budgets and its variation are more and more evolving. The ACRP Project DevoBeta-CC addresses the dynamics of long term sediment transport dynamics and its temporal altering. The focus is put on smaller tributary catchments enabling the model development. In total the data from ten catchments connected to the hydropower station Kaunertal (Tyrol/Austria) and eleven catchments linked to the power plant group Sellrain-Silz (Tyrol/Austria) are available. The considered catchments vary regarding their characteristics such as size (3 km³ to 27 km²), glaciation (0 % to 53 %), mean catchment slope (53 % to 92 %) and mean channel gradient (4 % to 49 %). The main data basis are records from the water intake structures operated (partly since 1965) by the TIWAG (Tiroler Wasserkraft AG). The sedimentation dynamics and operational flushings of the connected settling basins are used to measure the transported sediments. Since 1985 even high resolution data (15min intervals) are available. At selected catchments, the operationally recorded data (flushings, load membrane measurements,...) are verified within measuring campaigns using bed load traps upstream. Further, the sedimentation dynamics and grain size distributions in the settling basins are evaluated. Therefor two water intakes were put temporally out of operation, allowing an improved measurement of settled volumes by means of terrestrial surveying. Uncertainty assessments reveal an overall accuracy of estimated annual bed load volumes lower than a factor of two. Additionally, the data set enables to address sediment transport at a sub-annual basis, hence, the presented data set is unique regarding

  4. A rain splash transport equation assimilating field and laboratory measurements

    USGS Publications Warehouse

    Dunne, T.; Malmon, D.V.; Mudd, S.M.

    2010-01-01

    Process-based models of hillslope evolution require transport equations relating sediment flux to its major controls. An equation for rain splash transport in the absence of overland flow was constructed by modifying an approach developed by Reeve (1982) and parameterizing it with measurements from single-drop laboratory experiments and simulated rainfall on a grassland in East Africa. The equation relates rain splash to hillslope gradient, the median raindrop diameter of a storm, and ground cover density; the effect of soil texture on detachability can be incorporated from other published results. The spatial and temporal applicability of such an equation for rain splash transport in the absence of overland flow on uncultivated hillslopes can be estimated from hydrological calculations. The predicted transport is lower than landscape-averaged geologic erosion rates from Kenya but is large enough to modify short, slowly eroding natural hillslopes as well as microtopographic interrill surfaces between which overland flow transports the mobilized sediment. Copyright 2010 by the American Geophysical Union. Copyright 2010 by the American Geophysical Union.

  5. Precision Penning Trap Mass Measurements for Nuclear Structure at Triumf

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, A. A.; Dilling, J.; Andreoiu, C.; Brunner, T.; Chaudhuri, A.; Chowdhury, U.; Delheij, P.; Ettenauer, S.; Frekers, D.; Gallant, A. T.; Grossheim, A.; Gwinner, G.; Lennarz, A.; Mané, E.; Pearson, M. R.; Schultz, B. E.; Simon, M. C.; Simon, V. V.

    2013-03-01

    Precision determinations of ground state or even isomeric state masses reveal fingerprints of nuclear structure. In particular at the limits at existence for very neutron-rich or deficient isotopes, this allows one to find detailed information about nuclear structure from separation energies or binding energies. This is important to test theoretical predictions or to refine model approaches, for example for new "magic numbers," as predicted around N = 34, where strong indications exist that the inclusion of NNN forces in theoretical calculations for Ca isotopes leads to significantly better predictions for ground state binding energies. Similarly, halo nuclei present an excellent application for ab-initio theory, where ground state properties, like masses and radii, present prime parameters for testing our understanding of nuclear structure. Precision mass determinations at TRIUMF are carried out with the TITAN (TRIUMF's Ion Trap for Atomic and Nuclear science) system. It is an ion trap setup coupled to the on-line facility ISAC. TITAN has measured masses of isotopes as short-lived as 9 ms (almost an order of magnitude shorter-lived than any other Penning trap system) and the only one with charge breeding capabilities, a feature that allows us to boost the precision by almost 2 orders of magnitude. We recently were able to make use of this feature by measuring short-lived Rb-isotopes, up to 74Rb, and reaching the 12+ charge state, which together with other improvements lead to an increase in precision by a factor 36.

  6. Development of a continuous aerosol mass concentration measurement device.

    PubMed

    Bémer, D; Thomas, D; Contal, P; Subra, I

    2003-08-01

    A dynamic aerosol mass concentration measurement device has been developed for personal sampling. Its principle consists in sampling the aerosol on a filter and monitoring the change of pressure drop over time (Delta P). Ensuring that the linearity of the Delta P = f(mass of particles per unit area of filter) relationship has been well established, the change of concentration can be deduced. The response of the system was validated in the laboratory with a 3.5 microm alumina aerosol (mass median diameter) generated inside a 1-m(3) ventilated enclosure. As the theory predicted that the mass sensitivity of the system would vary inversely with the square of the particle diameter, only sufficiently fine aerosols were able to be measured. The system was tested in the field in a mechanical workshop in the vicinity of an arc-welding station. The aerosol produced by welding is indeed particularly well-adapted due to the sub-micronic size of the particles. The device developed, despite this limitation, has numerous advantages over other techniques: robustness, compactness, reliability of calibration, and ease of use.

  7. [Automatic Measurement of the Stellar Atmospheric Parameters Based Mass Estimation].

    PubMed

    Tu, Liang-ping; Wei, Hui-ming; Luo, A-li; Zhao, Yong-heng

    2015-11-01

    We have collected massive stellar spectral data in recent years, which leads to the research on the automatic measurement of stellar atmospheric physical parameters (effective temperature Teff, surface gravity log g and metallic abundance [Fe/ H]) become an important issue. To study the automatic measurement of these three parameters has important significance for some scientific problems, such as the evolution of the universe and so on. But the research of this problem is not very widely, some of the current methods are not able to estimate the values of the stellar atmospheric physical parameters completely and accurately. So in this paper, an automatic method to predict stellar atmospheric parameters based on mass estimation was presented, which can achieve the prediction of stellar effective temperature Teff, surface gravity log g and metallic abundance [Fe/H]. This method has small amount of computation and fast training speed. The main idea of this method is that firstly it need us to build some mass distributions, secondly the original spectral data was mapped into the mass space and then to predict the stellar parameter with the support vector regression (SVR) in the mass space. we choose the stellar spectral data from the United States SDSS-DR8 for the training and testing. We also compared the predicted results of this method with the SSPP and achieve higher accuracy. The predicted results are more stable and the experimental results show that the method is feasible and can predict the stellar atmospheric physical parameters effectively. PMID:26978937

  8. [Automatic Measurement of the Stellar Atmospheric Parameters Based Mass Estimation].

    PubMed

    Tu, Liang-ping; Wei, Hui-ming; Luo, A-li; Zhao, Yong-heng

    2015-11-01

    We have collected massive stellar spectral data in recent years, which leads to the research on the automatic measurement of stellar atmospheric physical parameters (effective temperature Teff, surface gravity log g and metallic abundance [Fe/ H]) become an important issue. To study the automatic measurement of these three parameters has important significance for some scientific problems, such as the evolution of the universe and so on. But the research of this problem is not very widely, some of the current methods are not able to estimate the values of the stellar atmospheric physical parameters completely and accurately. So in this paper, an automatic method to predict stellar atmospheric parameters based on mass estimation was presented, which can achieve the prediction of stellar effective temperature Teff, surface gravity log g and metallic abundance [Fe/H]. This method has small amount of computation and fast training speed. The main idea of this method is that firstly it need us to build some mass distributions, secondly the original spectral data was mapped into the mass space and then to predict the stellar parameter with the support vector regression (SVR) in the mass space. we choose the stellar spectral data from the United States SDSS-DR8 for the training and testing. We also compared the predicted results of this method with the SSPP and achieve higher accuracy. The predicted results are more stable and the experimental results show that the method is feasible and can predict the stellar atmospheric physical parameters effectively.

  9. LIF Diagnostic for Measuring Beam-Transport Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Jones, T. G.; Noonan, W. A.; Ottinger, P. F.

    1996-11-01

    A novel, spatially-resolved diagnostic is being developed to measure magnetic fields associated with intense ion beam propagation through a low-pressure gas, as is envisioned for light ion-driven ICF. The diagnostic technique uses laser-induced fluorescence (LIF) spectroscopy, and can be varied to measure either small or large fields. Small fields, as expected in ballistic transport with solenoidal lens focusing using ~ 1 Torr gas, produce Zeeman shifts, Δ λ_Z, smaller than the transition linewidth, Δ λ. High sensitivity to measure these shifts is achieved by a variation on the Babcock technique.^1 Large fields, as expected in self-pinched transport using 10--100 mTorr gas, produce Δ λZ larger than Δ λ, which can be measured with a high-resolution spectrometer. Results of proof-of-principle experiments using calibrated B-fields for both the small- and large-field techniques will be presented. Progress in fielding this diagnostic on the Gamble-II accelerator for beam-transport studies will also be presented. This work is supported by DoE through Sandia National Laboratories. ^ NRC-NRL Research Associate. ^ Present address University of Maryland, College Park, MD. ^1 W.A. Noonan, et al., accepted for publication in Rev. Sci. Instrum.

  10. Twin Knudsen Cell Configuration for Activity Measurements by Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Jacobson, N. S.

    1996-01-01

    A twin Knudsen cell apparatus for alloy activity measurements by mass spectrometry is described. Two Knudsen cells - one containing an alloy and one containing a pure component - are mounted on a single flange and translated into the sampling region via a motorized x-y table. Mixing of the molecular beams from the cells is minimized by a novel system of shutters. Activity measurements were taken on two well-characterized alloys to verify the operation of the system. Silver activity measurements are reported for Ag-Cu alloys and aluminum activity measurements are reported for Fe-Al alloys. The temperature dependence of activity for a 0.474 mol fraction Al-Fe alloy gives a partial molar heat of aluminum. Measurements taken with the twin cell show good agreement with literature values for these alloys.

  11. ISOLTRAP Mass Measurements for Weak-Interaction Studies

    SciTech Connect

    Kellerbauer, A.; Delahaye, P.; Herlert, A.; Audi, G.; Guenaut, C.; Lunney, D.; Beck, D.; Herfurth, F.; Kluge, H.-J.; Mukherjee, M.; Rodriguez, D.; Weber, C.; Yazidjian, C.; Blaum, K.; Bollen, G.; Schwarz, S.; George, S.; Schweikhard, L.

    2006-04-26

    The conserved-vector-current (CVC) hypothesis of the weak interaction and the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix are two fundamental postulates of the Standard Model. While existing data on CVC supports vector current conservation, the unitarity test of the CKM matrix currently fails by more than two standard deviations. High-precision mass measurements performed with the ISOLTRAP experiment at ISOLDE/CERN provide crucial input for these fundamental studies by greatly improving our knowledge of the decay energy of super-allowed {beta} decays. Recent results of mass measurements on the {beta} emitters 18Ne, 22Mg, 34Ar, and 74Rb as pertaining to weak-interaction studies are presented.

  12. UHECR mass composition measurement at Telescope Array via stereoscopic observation

    NASA Astrophysics Data System (ADS)

    Stroman, Thomas; Telescope Array Collaboration

    2015-04-01

    The masses of primary ultra-high-energy cosmic-ray (UHECR) nuclei cannot be measured directly on an individual basis, but constraints on the chemical composition can be inferred from the distributions of observable properties. The atmospheric slant depth at which a UHECR-induced extensive air shower reaches its maximum number of particles, Xmax, is particularly sensitive to the mass of the incident nucleus, occurring earlier in the shower's longitudinal development for heavier nuclei at a given energy. The Telescope Array in west-central Utah, the northern hemisphere's largest UHECR detector, is equipped for accurate Xmax and energy measurements via stereoscopic fluorescence observation. Using data from seven years of operation, we will present Xmax distributions at several energies E >10 18 . 2eV , and compare them to distributions predicted by detailed detector simulations under an assortment of assumed UHECR compositions and high-energy hadronic interaction models.

  13. Measurement of the mass difference between top and antitop quarks

    SciTech Connect

    Chatrchyan, Serguei; et al.

    2012-06-01

    A measurement of the mass difference between the top and the antitop quark (Delta m(t) = m(t) - m(anti-t)) is performed using events with a muon or an electron and at least four jets in the final state. The analysis is based on data collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.96 +/- 0.11 inverse femtobarns, and yields the value of Delta m(t) = -0.44 +/- 0.46 (stat) +/- 0.27 (syst) GeV. This result is consistent with equality of particle and antiparticle masses required by CPT invariance, and provides a significantly improved precision relative to existing measurements.

  14. Mean Flow Velocities and Mass Transport for Equatorially-Trapped Water Waves with an Underlying Current

    NASA Astrophysics Data System (ADS)

    Henry, David; Sastre-Gomez, Silvia

    2016-04-01

    In this paper we present an analysis of the mean flow velocities, and related mass transport, which are induced by certain equatorially-trapped water waves. In particular, we examine a recently-derived exact and explicit solution to the geophysical governing equations in the {β} -plane approximation at the equator which incorporates a constant underlying current.

  15. Servo-amplifiers for ion current measurement in mass spectrometry

    USGS Publications Warehouse

    Stacey, J.S.; Russell, R.D.; Kollar, F.

    1965-01-01

    A servo-voltmeter can provide a useful alternative to the d.c. amplifier or vibrating reed electrometer for the accurate measurement of mass spectrometer ion currents, and has some advantages which recommend its use in certain applications. A generalized analysis based on servomechanism theory is presented as an aid for understanding the design criteria for this type of device. Two existing systems are described and their operation and performance are examined.

  16. Present status of the MISTRAL mass measurement experiment

    SciTech Connect

    Monsanglant, C.; Audi, G.; Doubre, H.; Duma, M.; Jacotin, M.; Kepinski, J.-F.; Le Scornet, G.; Saint Simon, M. de; Thibault, C.; Borcea, C.; Lebee, G.; Lunney, M. D.; Toader, C.

    1998-10-26

    The MISTRAL experiment for measuring masses of very short-lived nuclides at ISOLDE has been installed during the summer of 1997 and has had its first radioactive beam in November 1997. Tests are presently been carried out to study all possible systematic effects. This paper recalls the basic principles of the Smith-type radio-frequency spectrometer, gives its present characteristics and limitations, and describes the methods used to improve its performances.

  17. Momentum and mass transport over a superhydrophobic bubble mattress: the influence of interface geometry

    NASA Astrophysics Data System (ADS)

    Tsai, Peichun Amy; Haase, A. Sander; Karatay, Elif; Lammertink, Rob; Soft Matter, Fluidics; Interfaces Group Team

    2013-11-01

    We numerically investigate the influence of interface geometry on momentum and mass transport on a partially slippery bubble mattress. The bubble mattress, forming a superhydrophobic substrate, consists of an array of slippery (shear-free) gas bubbles with (no-slip) solids walls in between. We consider steady pressure-driven laminar flow over the bubble mattress, with a solute being supplied from the gas bubbles. The results show that solute transport can be enhanced significantly due to effective slippage, compared to a fully saturated no-slip wall. The enhancement depends on the interface geometry of the bubble mattress, i.e. on the bubble size, protrusion angle, and surface porosity. In addition, we demonstrate that the mass transfer enhancement disappears below a critical bubble size. The effective slip vanishes for very small bubbles, whereby interfacial transport becomes diffusion dominated. For large bubbles, solute transport near the interface is greatly enhanced by convection. The results provide insight into the optimal design of ultra-hydrophobic bubble mattresses to enhance both momentum and mass transport.

  18. Anatomy of mass transport deposits in the Dead Sea: sedimentary processes in an active tectonic hypersaline basin

    NASA Astrophysics Data System (ADS)

    Waldmann, Nicolas; Hadzhiivanova, Elitsa; Neugebauer, Ina; Brauer, Achim; Schwab, Markus; Frank, Ute; Dulski, Peter

    2014-05-01

    Continental archives such as interplate endorheic lacustrine sedimentary basins provide an excellent source of data for studying regional climate, seismicity and environmental changes through time. Such is the case for the sediments that were deposited in the Dead Sea basin, a tectonically active pull-apart structure along the Dead Sea fault (DSF). This elongated basin is characterized by steep slopes and a deep and flat basin-floor, which are constantly shaped by seismicity and climate. In this study, we present initial results on the sedimentology and internal structure of mass transport deposits in the Pleistocene Dead Sea. The database used for this study consists of a long core retrieved at ~300 m water depth in the deepest part of the Dead Sea as part of an international scientific effort under the auspice of the ICDP. Micro-facies analysis coupled by elemental scanning (µXRF), granulometry and petrophysical measurements (magnetic susceptibility) have been carried out on selected intervals in order to decipher and identify the source-to-sink processes and controlling mechanisms behind the formation of mass transport deposits. The findings of this study allowed defining and characterizing the mass transport deposits into separate sedimentary facies according to the lake level and limnological conditions. Investigating sediments from the deep Dead Sea basin allowed better understanding and deciphering the depositional processes in relation with the tectonic forces shaping this basin.

  19. Radionuclide measurements by accelerator mass spectrometry at Arizona

    NASA Technical Reports Server (NTRS)

    Jull, A. J. T.; Donahue, D. J.; Zabel, T. H.

    1986-01-01

    Over the past years, Tandem Accelerator Mass Spectrometry (TAMS) has become established as an important method for radionuclide analysis. In the Arizona system the accelerator is operated at a thermal voltage of 1.8MV for C-14 analysis, and 1.6 to 2MV for Be-10. Samples are inserted into a cesium sputter ion source in solid form. Negative ions sputtered from the target are accelerated to about 25kV, and the injection magnet selects ions of a particular mass. Ions of the 3+ charge state, having an energy of about 9MeV are selected by an electrostatic deflector, surviving ions pass through two magnets, where only ions of the desired mass-energy product are selected. The final detector is a combination ionization chamber to measure energy loss (and hence, Z), and a silicon surface-barrier detector which measures residual energy. After counting the trace iosotope for a fixed time, the injected ions are switched to the major isotope used for normalization. These ions are deflected into a Faraday cup after the first high-energy magnet. Repeated measurements of the isotope ratio of both sample and standards results in a measurement of the concentration of the radionuclide. Recent improvements in sample preparation for C-14 make preparation of high-beam current graphite targets directly from CO2 feasible. Except for some measurements of standards and backgrounds for Be-10 measurements to date have been on C-14. Although most results have been in archaeology and quaternary geology, studies have been expanded to include cosmogenic C-14 in meteorites. The data obtained so far tend to confirm the antiquity of Antarctic meteorites from the Allan Hills site. Data on three samples of Yamato meteorites gave terrestrial ages of between about 3 and 22 thousand years.

  20. Focused transport of energetic particles along magnetic field lines draped around a coronal mass ejection

    NASA Technical Reports Server (NTRS)

    Tan, L. C.; Mason, G. M.; Lee, M. A.; Klecker, B.; Ipavich, F. M.

    1992-01-01

    Evidence is presented for focused transport of energetic particles along magnetic field lines draped around a coronal mass ejection. This evidence was obtained with the University of Maryland/Max-Planck-Institute experiment on the ISEE-3 spacecraft during the decay phase of the June 6, 1979, solar particle event. During the early portion of the decay phase of this event, interplanetary magnetic field lines were apparently draped around a coronal mass ejection, leading to a small focusing length on the western flank where ISEE 3 was located. A period of very slow decrease of particle intensity was observed, along with large sunward anisotropy in the solar wind frame, which is inconsistent with predictions of the standard Fokker-Planck equation models for diffusive transport. It was found possible to fit the observations, assuming that focused transport dominates and that the particle pitch angle scattering is isotropic.

  1. Measurement of bedload transport in sand-bed rivers: a look at two indirect sampling methods

    USGS Publications Warehouse

    Holmes, Robert R.; Gray, John R.; Laronne, Jonathan B.; Marr, Jeffrey D.G.

    2010-01-01

    Sand-bed rivers present unique challenges to accurate measurement of the bedload transport rate using the traditional direct sampling methods of direct traps (for example the Helley-Smith bedload sampler). The two major issues are: 1) over sampling of sand transport caused by “mining” of sand due to the flow disturbance induced by the presence of the sampler and 2) clogging of the mesh bag with sand particles reducing the hydraulic efficiency of the sampler. Indirect measurement methods hold promise in that unlike direct methods, no transport-altering flow disturbance near the bed occurs. The bedform velocimetry method utilizes a measure of the bedform geometry and the speed of bedform translation to estimate the bedload transport through mass balance. The bedform velocimetry method is readily applied for the estimation of bedload transport in large sand-bed rivers so long as prominent bedforms are present and the streamflow discharge is steady for long enough to provide sufficient bedform translation between the successive bathymetric data sets. Bedform velocimetry in small sandbed rivers is often problematic due to rapid variation within the hydrograph. The bottom-track bias feature of the acoustic Doppler current profiler (ADCP) has been utilized to accurately estimate the virtual velocities of sand-bed rivers. Coupling measurement of the virtual velocity with an accurate determination of the active depth of the streambed sediment movement is another method to measure bedload transport, which will be termed the “virtual velocity” method. Much research remains to develop methods and determine accuracy of the virtual velocity method in small sand-bed rivers.

  2. Measurement of the top quark mass at D0

    SciTech Connect

    Varnes, E.W.; D0 Collaboration

    1996-11-01

    D{null} has measured the top quark mass using a sample of 32 single- lepton events selected from approximately 115 pb{sup -1} of {radical}s = 1.8 TeV {ital p}{ital {anti p}} collisions collected from 1992-1996. The result is {ital m}{sub t} = 169 {+-} 8({ital stat}){+-} 8 ({ital syst}) GeV/c{sup 2}. Using a sample of 3 {ital e{mu}} events, D{null} measures {ital m}{sub t} = 158 {+-} 24({ital stat}) {+-} 10({ital syst}) GeV/c{sup 2}.

  3. Thermodynamic Activity Measurements with Knudsen Cell Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Copland, Evan H.; Jacobson, Nathan S.

    2001-01-01

    Coupling the Knudsen effusion method with mass spectrometry has proven to be one of the most useful experimental techniques for studying the equilibrium between condensed phases and complex vapors. The Knudsen effusion method involves placing a condensed sample in a Knudsen cell, a small "enclosure", that is uniformly heated and held until equilibrium is attained between the condensed and vapor phases. The vapor is continuously sampled by effusion through a small orifice in the cell. A molecular beam is formed from the effusing vapor and directed into a mass spectrometer for identification and pressure measurement of the species in the vapor phase. Knudsen cell mass spectrometry (KCMS) has been used for nearly fifty years now and continues to be a leading technique for obtaining thermodynamic data. Indeed, much of the well-established vapor specie data in the JANAF tables has been obtained from this technique. This is due to the extreme versatility of the technique. All classes of materials can be studied and all constituents of the vapor phase can be measured over a wide range of pressures (approximately 10(exp -4) to 10(exp -11) bar) and temperatures (500-2800 K). The ability to selectively measure different vapor species makes KCMS a very powerful tool for the measurement of component activities in metallic and ceramic solutions. Today several groups are applying KCMS to measure thermodynamic functions in multicomponent metallic and ceramic systems. Thermodynamic functions, especially component activities, are extremely important in the development of CALPHAD (Calculation of Phase Diagrams) type thermodynamic descriptions. These descriptions, in turn, are useful for modeling materials processing and predicting reactions such as oxide formation and fiber/matrix interactions. The leading experimental methods for measuring activities are the Galvanic cell or electro-motive force (EMF) technique and the KCMS technique. Each has specific advantages, depending on

  4. Investigating Mass Transport Limitations on Xylan Hydrolysis During Dilute Acid Pretreatment of Poplar

    SciTech Connect

    Mittal, Ashutosh; Pilath, Heid M.; Parent, Yves; Chatterjee, Siddharth G.; Donohoe, Bryon S.; Yarbrough, John M.; Himmel, Michael E.; Nimlos, Mark R.; Johnson, David K.

    2014-04-28

    Mass transport limitations could be an impediment to achieving high sugar yields during biomass pretreatment and thus be a critical factor in the economics of biofuels production. The objective of this work was to study the mass transfer restrictions imposed by the structure of biomass on the hydrolysis of xylan during dilute acid pretreatment of biomass. Mass transfer effects were studied by pretreating poplar wood at particle sizes ranging from 10 micrometers to 10 mm. This work showed a significant reduction in the rate of xylan hydrolysis in poplar when compared to the intrinsic rate of hydrolysis for isolated xylan that is possible in the absence of mass transfer. In poplar samples we observed no significant difference in the rates of xylan hydrolysis over more than two orders of magnitude in particle size. It appears that no additional mass transport restrictions are introduced by increasing particle size from 10 micrometers to 10 mm. This work suggests that the rates of xylan hydrolysis in biomass particles are limited primarily by the diffusion of hydrolysis products out of plant cell walls. A mathematical description is presented to describe the kinetics of xylan hydrolysis that includes transport of the hydrolysis products through biomass into the bulk solution. The modeling results show that the effective diffusion coefficient of the hydrolysis products in the cell wall is several orders of magnitude smaller than typical values in other applications signifying the role of plant cell walls in offering resistance to diffusion of the hydrolysis products.

  5. Mass transport in a porous microchannel for non-Newtonian fluid with electrokinetic effects.

    PubMed

    Mondal, Sourav; De, Sirshendu

    2013-03-01

    Quantification of mass transfer in porous microchannel is of paramount importance in several applications. Transport of neutral solute in presence of convective-diffusive EOF having non-Newtonian rheology, in a porous microchannel was presented in this article. The governing mass transfer equation coupled with velocity field was solved along with associated boundary conditions using a similarity solution method. An analytical solution of mass transfer coefficient and hence, Sherwood number were derived from first principles. The corresponding effects of assisting and opposing pressure-driven flow and EOF were also analyzed. The influence of wall permeation, double-layer thickness, rheology, etc. on the mass transfer was also investigated. Permeation at the wall enhanced the mass transfer coefficient more than five times compared to impervious conduit in case of pressure-driven flow assisting the EOF at higher values of κh. Shear thinning fluid exhibited more enhancement of Sherwood number in presence of permeation compared to shear thickening one. The phenomenon of stagnation was observed at a particular κh (∼2.5) in case of EOF opposing the pressure-driven flow. This study provided a direct quantification of transport of a neutral solute in case of transdermal drug delivery, transport of drugs from blood to target region, etc. PMID:23192435

  6. Mass transport in a porous microchannel for non-Newtonian fluid with electrokinetic effects.

    PubMed

    Mondal, Sourav; De, Sirshendu

    2013-03-01

    Quantification of mass transfer in porous microchannel is of paramount importance in several applications. Transport of neutral solute in presence of convective-diffusive EOF having non-Newtonian rheology, in a porous microchannel was presented in this article. The governing mass transfer equation coupled with velocity field was solved along with associated boundary conditions using a similarity solution method. An analytical solution of mass transfer coefficient and hence, Sherwood number were derived from first principles. The corresponding effects of assisting and opposing pressure-driven flow and EOF were also analyzed. The influence of wall permeation, double-layer thickness, rheology, etc. on the mass transfer was also investigated. Permeation at the wall enhanced the mass transfer coefficient more than five times compared to impervious conduit in case of pressure-driven flow assisting the EOF at higher values of κh. Shear thinning fluid exhibited more enhancement of Sherwood number in presence of permeation compared to shear thickening one. The phenomenon of stagnation was observed at a particular κh (∼2.5) in case of EOF opposing the pressure-driven flow. This study provided a direct quantification of transport of a neutral solute in case of transdermal drug delivery, transport of drugs from blood to target region, etc.

  7. Air Mass Origin as a Diagnostic of Seasonally-Varying Transport into the Arctic

    NASA Astrophysics Data System (ADS)

    Orbe, C.; Waugh, D. W.; Holzer, M. B.; Newman, P. A.; Polvani, L. M.; Oman, L.; Li, F.

    2013-12-01

    While the signatures of the seasonal cycle on basic state variables such as temperature, winds and on chemical composition have been explored in depth, its signature on air mass composition has received relatively little attention. To this end, we present the first analysis of the seasonally varying transport from the northern hemisphere (NH) midlatitudes into the Arctic using rigorously defined air masses. The fractional contribution from each air mass partitions Arctic air according to where it was last in the planetary boundary layer (PBL) at midlatitudes over the Pacific and Atlantic oceans, North America, Europe, and Asia. Air mass fractions are computed using the coupled climate-chemistry model GEOSCCM subject to fixed present-day climate forcings. We find that during DJF 48% of the air in the free troposphere poleward of 60N was last at midlatitudes primarily at the Pacific and Atlantic oceans, at 20% and 10% respectively. During JJA, however, the largest contributions to Arctic air come from Asian and North American source regions, revealing that transport from the industrialized midlatitude regions dominates during boreal summer. Preliminary calculations of future air masses for a model integration subject to A1B greenhouse gases also reveal the model's climate change response in arctic air mass composition. In concert with weakened tropospheric eddy kinetic energy and a weakened Hadley cell, we find that changes in annual mean arctic air mass fractions are of the order 10%, with increased contributions from air that was last in contact with the PBL over North America and over the Atlantic and Pacific oceans. Air-mass fractions, and their changes, thus help to isolate the role of transport to changes in composition, which are not only driven by changes in chemistry and emissions but also crucially by changes in atmospheric flow.

  8. Review on measurement techniques of transport properties of nanowires.

    PubMed

    Rojo, Miguel Muñoz; Calero, Olga Caballero; Lopeandia, A F; Rodriguez-Viejo, J; Martín-Gonzalez, Marisol

    2013-12-01

    Physical properties at the nanoscale are novel and different from those in bulk materials. Over the last few decades, there has been an ever growing interest in the fabrication of nanowire structures for a wide variety of applications including energy generation purposes. Nevertheless, the study of their transport properties, such as thermal conductivity, electrical conductivity or Seebeck coefficient, remains an experimental challenge. For instance, in the particular case of nanostructured thermoelectrics, theoretical calculations have shown that nanowires offer a promising way of enhancing the hitherto low efficiency of these materials in the conversion of temperature differences into electricity. Therefore, within the thermoelectrical community there has been a great experimental effort in the measurement of these quantities in actual nanowires. The measurements of these properties at the nanoscale are also of interest in fields other than energy, such as electrical components for microchips, field effect transistors, sensors, and other low scale devices. For all these applications, knowing the transport properties is mandatory. This review deals with the latest techniques developed to perform the measurement of these transport properties in nanowires. A thorough overview of the most important and modern techniques used for the characterization of different kinds of nanowires will be shown. PMID:24113712

  9. LIF Diagnostic for Measuring Beam-Transport Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Jones, T. G.; Hinshelwood, D. D.; Neri, J. M.; Ottinger, P. F.; Noonan, W. A.

    1997-11-01

    A novel, spatially-resolved diagnostic is being developed to measure magnetic fields associated with intense ion beam propagation through a low-pressure gas, as is envisioned for light ion-driven ICF. The diagnostic technique uses laser-induced fluorescence (LIF) spectroscopy, and can be varied to measure either small or large fields. Small fields, as expected in ballistic transport with solenoidal lens focusing using ~ 1 Torr gas, produce Zeeman shifts, Δ λ_Z, smaller than the transition linewidth, Δ λ. High sensitivity to measure these shifts is achieved by a variation on the Babcock technique.^1 Large fields, as expected in self-pinched transport using 1--100 mTorr gas, produce Δ λZ larger than Δ λ. These Δ λZ will be resolved using an etalon as a narrowband, high-throughput optical filter. Available results from benchtop experiments using calibrated B-fields for both the small- and large-field techniques, and progress in fielding this diagnostic on the Gamble-II accelerator for beam-transport studies will be presented. Work supported by DOE through Sandia National Laboratories. ^ National Research Council Research Associate. ^ Present address University of Maryland, College Park, MD. ^1 W.A. Noonan, et al., Rev. Sci. Instrum. 68, 1032 (1997).

  10. Review on measurement techniques of transport properties of nanowires.

    PubMed

    Rojo, Miguel Muñoz; Calero, Olga Caballero; Lopeandia, A F; Rodriguez-Viejo, J; Martín-Gonzalez, Marisol

    2013-12-01

    Physical properties at the nanoscale are novel and different from those in bulk materials. Over the last few decades, there has been an ever growing interest in the fabrication of nanowire structures for a wide variety of applications including energy generation purposes. Nevertheless, the study of their transport properties, such as thermal conductivity, electrical conductivity or Seebeck coefficient, remains an experimental challenge. For instance, in the particular case of nanostructured thermoelectrics, theoretical calculations have shown that nanowires offer a promising way of enhancing the hitherto low efficiency of these materials in the conversion of temperature differences into electricity. Therefore, within the thermoelectrical community there has been a great experimental effort in the measurement of these quantities in actual nanowires. The measurements of these properties at the nanoscale are also of interest in fields other than energy, such as electrical components for microchips, field effect transistors, sensors, and other low scale devices. For all these applications, knowing the transport properties is mandatory. This review deals with the latest techniques developed to perform the measurement of these transport properties in nanowires. A thorough overview of the most important and modern techniques used for the characterization of different kinds of nanowires will be shown.

  11. Mass-conserving tracer transport modelling on a reduced latitude-longitude grid

    NASA Astrophysics Data System (ADS)

    Belikov, D.; Maksyutov, S.; Miyasaka, T.; Saeki, T.; Zhuravlev, R.; Kiryushov, B.

    2010-10-01

    The need to perform long-term simulations with reasonable accuracy has led to the development of mass-conservative and efficient numerical methods for solving the transport equation in forward and inverse models. We designed and implemented a flux-form (Eulerian) tracer transport algorithm in the National Institute for Environmental Studies Transport Model (NIES TM), which is used for simulating diurnal and synoptic-scale variations of tropospheric long-lived constituents, as well as their seasonal and inter-annual variability. Implementation of the flux-form method requires the mass conservative wind fields. However, the model is off-line and is driven by datasets from a global atmospheric model or data assimilation system, in which vertically integrated mass changes are not in balance with the surface pressure tendency and mass conservation is not achieved. To rectify the mass-imbalance, a flux-correction method is employed. To avoid singularity near the poles caused by the small grid size arising from the meridional convergence problem, the proposed model uses a reduced latitude-longitude grid scheme, in which the grid size is doubled several times approaching the poles. This approach overcomes the Courant condition in the Polar Regions, maintains a reasonably high integration time-step and ensures adequate model performance during simulations. To assess the model performance, we performed global transport simulations for SF6, 222Rn and CO2. The results were compared with observations available from the World Data Centre for Greenhouse Gases, GLOBALVIEW and the Hateruma monitoring station, Japan. Overall, the results show that the proposed flux-form version of NIES TM can produce tropospheric tracer transport more realistically than previously possible. The reasons for this improvement are discussed.

  12. A mass-conserving advection scheme for offline simulation of scalar transport in coastal ocean models

    NASA Astrophysics Data System (ADS)

    Gillibrand, P. A.; Herzfeld, M.

    2016-05-01

    We present a flux-form semi-Lagrangian (FFSL) advection scheme designed for offline scalar transport simulation with coastal ocean models using curvilinear horizontal coordinates. The scheme conserves mass, overcoming problems of mass conservation typically experienced with offline transport models, and permits long time steps (relative to the Courant number) to be used by the offline model. These attributes make the method attractive for offline simulation of tracers in biogeochemical or sediment transport models using archived flow fields from hydrodynamic models. We describe the FFSL scheme, and test it on two idealised domains and one real domain, the Great Barrier Reef in Australia. For comparison, we also include simulations using a traditional semi-Lagrangian advection scheme for the offline simulations. We compare tracer distributions predicted by the offline FFSL transport scheme with those predicted by the original hydrodynamic model, assess the conservation of mass in all cases and contrast the computational efficiency of the schemes. We find that the FFSL scheme produced very good agreement with the distributions of tracer predicted by the hydrodynamic model, and conserved mass with an error of a fraction of one percent. In terms of computational speed, the FFSL scheme was comparable with the semi-Lagrangian method and an order of magnitude faster than the full hydrodynamic model, even when the latter ran in parallel on multiple cores. The FFSL scheme presented here therefore offers a viable mass-conserving and computationally-efficient alternative to traditional semi-Lagrangian schemes for offline scalar transport simulation in coastal models.

  13. Progress on a Rayleigh Scattering Mass Flux Measurement Technique

    NASA Technical Reports Server (NTRS)

    Mielke-Fagan, Amy F.; Clem, Michelle M.; Elam, Kristie A.; Hirt, Stefanie M.

    2010-01-01

    A Rayleigh scattering diagnostic has been developed to provide mass flux measurements in wind tunnel flows. Spectroscopic molecular Rayleigh scattering is an established flow diagnostic tool that has the ability to provide simultaneous density and velocity measurements in gaseous flows. Rayleigh scattered light from a focused 10 Watt continuous-wave laser beam is collected and fiber-optically transmitted to a solid Fabry-Perot etalon for spectral analysis. The circular interference pattern that contains the spectral information that is needed to determine the flow properties is imaged onto a CCD detector. Baseline measurements of density and velocity in the test section of the 15 cm x 15 cm Supersonic Wind Tunnel at NASA Glenn Research Center are presented as well as velocity measurements within a supersonic combustion ramjet engine isolator model installed in the tunnel test section.

  14. First Run II Measurement of the W Boson Mass

    SciTech Connect

    Aaltonen, T.; Abulencia, A.; Adelman, J.; Akimoto, T.; Albrow, Michael G.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E.; Anastassov, A.; Annovi, A.; Antos, J.; /Comenius U. /Fermilab

    2007-08-01

    We describe a measurement of the W boson mass m{sub W} using 200 pb{sup -1} of {radical}s = 1.96 TeV p{bar p} collision data taken with the CDF II detector. With a sample of 63,964 W {yields} e{nu} candidates and 51,128 W {yields} {mu}{nu} candidates, we measure m{sub W} = [80.413 {+-} 0.034(stat.) {+-} 0.034 (sys.) = 80.413 {+-} 0.048] GeV/c{sup 2}. This is the single most precise m{sub W} measurement to date. When combined with other measured electroweak parameters, this result further constrains the properties of new unobserved particles coupling to W and Z bosons.

  15. New Satellite Laser Ranging TRF and EOP Series for Mass Transport Studies in the Earth System

    NASA Astrophysics Data System (ADS)

    Pavlis, E. C.

    2001-12-01

    The new millennium has started on the right note for geodesy. We finally see a series of gravity mapping missions materialize. What now becomes important is that well-established geodetic techniques rise to the challenge of validating and complementing the data these new missions will deliver. An area where this is likely to be important is the temporal variations in the zonal gravitational field and its very low degree and order components in general. Satellite laser ranging (SLR) has for a long time monitored the continuous redistribution of mass within the Earth system through concomitant changes in the Stokes' coefficients of the terrestrial gravity field. Secular changes in J2 due to post-glacial relaxation have been observed since many years and similar changes in J3, J4 J5, etc. are attributed to changes in the ice sheets of Greenland and Antarctica. Seasonal changes in these coefficients have also been closely correlated with mass transfer in the atmosphere and oceans. JCET's latest analysis of the 1993-present SLR data set from LAGEOS and LAGEOS 2 data for the IERS (International Earth Rotation Service) Terrestrial Reference Frame (ITRF) development, includes the weekly monitoring of such compound changes in the low degree and order harmonics. This latest solution (2001) incorporates several important changes in the modeling of SLR data with resulting improvements in the geophysical products. Along with the static parameters of the TRF we have determined a time series of variations of its origin with respect to the center of mass of the Earth system (geocenter). These estimates provide a measure of the total motion due to all sources of mass transport within the Earth system and can be used to either complement the estimates from the future missions or to validate them through comparisons with their estimates for the same quantities. The data were reduced using NASA Goddard's GEODYN/SOLVE II software, resulting to a final RMS error of ~8 mm - close to the

  16. Multiscale mass transport in z ˜6 galactic discs: fuelling black holes

    NASA Astrophysics Data System (ADS)

    Prieto, Joaquin; Escala, Andrés

    2016-08-01

    By using Adaptive Mesh Refinement cosmological hydrodynamic N-body zoom-in simulations, with the RAMSES code, we studied the mass transport processes on to galactic nuclei from high redshift up to z ˜6. Due to the large dynamical range of the simulations, we were able to study the mass accretion process on scales from ˜50 kpc to ˜few 1 pc. We studied the black hole (BH) growth on to the Galactic Centre in relation with the mass transport processes associated to both the Reynolds stress and the gravitational stress on the disc. Such methodology allowed us to identify the main mass transport process as a function of the scales of the problem. We found that in simulations that include radiative cooling and supernovae feedback, the supermassive black hole (SMBH) grows at the Eddington limit for some periods of time presenting ≈ 0.5 throughout its evolution. The α parameter is dominated by the Reynolds term, αR, with αR ≫ 1. The gravitational part of the α parameter, αG, has an increasing trend towards the Galactic Centre at higher redshifts, with values αG ˜1 at radii ≲ few 101 pc contributing to the BH fuelling. In terms of torques, we also found that gravity has an increasing contribution towards the Galactic Centre at earlier epochs with a mixed contribution above ˜100 pc. This complementary work between pressure gradients and gravitational potential gradients allows an efficient mass transport on the disc with average mass accretion rates of the order of ˜few 1 M⊙ yr-1. These levels of SMBH accretion rates found in our cosmological simulations are needed in all models of SMBH growth that attempt to explain the formation of redshift 6-7 quasars.

  17. Mass Influx of Cosmic Dust Estimated From Vertical Transport of Meteoric Metals

    NASA Astrophysics Data System (ADS)

    Liu, Alan Z.; Guo, Yafang; Gardner, Chester S.

    2016-04-01

    The mesospheric metal layers are formed by the vaporization of high-speed cosmic dust particles in the lower thermosphere and upper mesosphere. The vaporized atoms and ions are transported downward by waves and turbulence to chemical sinks below 85 km, where they form stable compounds. These compounds condense onto meteoric smoke particles and are then transported to the winter pole where they eventually settle onto the surface. The downward fluxes of the metal atoms are directly related to their meteoric influxes and chemical loss rates. In this paper we use Doppler lidar measurements of Na and Fe fluxes made by the University of Illinois and University of Colorado groups, and a chemical ablation model (CABMOD) developed at the University of Leeds, to constrain the velocity/mass distribution of the meteoroids entering the atmosphere and to derive an improved estimate for the global influx of cosmic dust. We find that the particles responsible for injecting a large fraction of the ablated material into the Earth's upper atmosphere, enter at relatively slow speeds and originate primarily from the Jupiter Family of Comets. The global mean Na influx is 21,500±1,100 atoms/cm2/s, which equals 372±18 kg/d for the global input of Na vapor and 186±24 t/d for the global influx of cosmic dust. The global mean Fe influx is 131,000±36,000 atoms/cm2/s, which equals 5.5±1.5 t/d for the global input of Na vapor.

  18. Measurements of CO in an aircraft experiment and their correlation with biomass burning and air mass origin in South America

    NASA Astrophysics Data System (ADS)

    Boian, C.; Kirchhoff, V. W. J. H.

    Carbon monoxide (CO) measurements are obtained in an aircraft experiment during 1-7 September 2000, conducted over Central Brazil in a special region of anticyclonic circulation. This is a typical transport regime during the dry season (July-September), when intense biomass burning occurs, and which gives origin to the transport of burning poluents from the source to distant regions. This aircraft experiment included in situ measurements of CO concentrations in three different scenarios: (1) areas of fresh biomass burning air masses, or source areas; (2) areas of aged biomass burning air masses; and (3) areas of clean air or pristine air masses. The largest CO concentrations were of the order of 450 ppbv in the source region near Conceicao do Araguaia (PA), and the smallest value near 100 ppbv, was found in pristine air masses, for example, near the northeast coastline (clean air, or background region). The observed concentrations were compared to the number of fire pixels seen by the AVHRR satellite instrument. Backward isentropic trajectories were used to determine the origin of the air masses at each sampling point. From the association of the observed CO mixing ratios, fire pixels and air mass trajectories, the previous scenarios may be subdivided as follows: (1a) source regions of biomass burning with large CO concentrations; (1b) regions with few local fire pixels and absence of contributions by transport. Areas with these characteristics include the northeast region of Brazil; (1c) regions close to the source region and strongly affected by transport (region of Para and Amazonas); (2) regions that have a consistent convergence of air masses, that have traveled over biomass burning areas during a few days (western part of the Cerrado region); (3a) Pristine air masses with origin from the ocean; (3b) regions with convergent transport that has passed over areas of no biomass burning, such as frontal weather systems in the southern regions.

  19. Measuring a Black Hole's Mass with Robotic Telescopes

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-11-01

    Who needs humans? Robotic observations made by telescopes in the Las Cumbres Observatory Global Telescope network (LCOGT) have tracked variability in the active galaxy Arp 151 over 200 days. These observations have proven to be enough information to estimate the mass of the black hole at the galaxys center.Mapping EchoesMeasuring the masses of supermassive black holes is notoriously difficult. Except in the few cases where were able to resolve actual objects orbiting around the supermassive black hole (for instance, in the case of the black hole at the center of the Milky Way), our estimates of black-hole mass must come from indirect measurements.One clever approach is called reverberation mapping. In an active galactic nucleus (AGN), continuum emission from the black holes accretion disk photoionizes gas clouds in the nearby broad-line region, causing the clouds to emit light. In reverberation mapping, we track the time lag between variability in the disks continuum emission and the clouds broad-line emission, obtaining a distance scale. Combining this information with a velocity (provided by the broad-line width) allows us to infer the enclosed mass in this case, that of the black hole.So whats the catch? Getting this information requires a lot of man-hours and telescope-hours, because AGN need to be observed over long periods of time to see the variability and the lags needed to make these inferences. This is where LCOGT comes in.Robotic NetworkArp 151 light curves. The top panel shows the continuum emission from the disk; the remaining panels show various emission lines from the broad-line-region clouds. The variability of the line emission lags slightly behind that of the continuum emission. [Valenti et al. 2015]LCOGT is a completely robotic telescope network. Everything from the scheduling to the telescope alignment is done without human involvement. Because of this feature, the LCOGT is an ideal facility for conducting time-intensive observations of AGN

  20. Millisecond measurement of transport during and after an electroporation pulse.

    PubMed Central

    Prausnitz, M R; Corbett, J D; Gimm, J A; Golan, D E; Langer, R; Weaver, J C

    1995-01-01

    Electroporation involves the application of an electric field pulse that creates transient aqueous pathways in lipid bilayer membranes. Transport through these pathways can occur by different mechanisms during and after a pulse. To determine the time scale of transport and the mechanism(s) by which it occurs, efflux of a fluorescent molecule, calcein, across erythrocyte ghost membranes was measured with a fluorescence microscope photometer with millisecond time resolution during and after electroporation pulses several milliseconds in duration. One of four outcomes was typically observed. Ghosts were: (1) partially emptied of calcein, involving efflux primarily after the pulse; (2) completely emptied of calcein, involving efflux primarily after the pulse; (3) completely emptied of calcein, involving efflux both during and after the pulse; or (4) completely emptied of calcein, involving efflux primarily during the pulse. Partial emptying, involving significant efflux during the pulse, was generally not observed. We conclude that under some conditions transport caused by electroporation occurs predominantly by electrophoresis and/or electroosmosis during a pulse, although under other conditions transport occurs in part or almost completely by diffusion within milliseconds to seconds after a pulse. PMID:7612828

  1. Measurement of Flow and Transport in Macroporous Soils

    NASA Astrophysics Data System (ADS)

    Köhne, J. M.; Mohanty, B. P.; Castiglione, P.

    2002-12-01

    Preferential flow in agricultural regions poses a serious environmental threat by allowing chemicals to bypass the soil matrix and to be channeled into ground water. Although a long-known phenomenon, our understanding of and ability to predict macropore flow and transport remain far from complete. To analyze the processes that control macropore flow in soil, we have built large (25 cm diam., 80 cm length) repacked soil columns with different macropore/matrix domain configurations: (i) In column I, multiple macropores were created in one-half cross-section. Water flow and chloride transport experiments were performed for macropores open to the atmosphere and buried-macropores. Measurements at the bottom boundary as well as across the profile consistently revealed the higher degree of preferential flow in open macropores as compared to the buried macropores. (ii) In column II, a single cylindrical macropore was located in the center of the surrounding soil matrix. We conducted experiments of water flow and solute transport using KBr as a conservative tracer. In the soil matrix, TDR-probes measure soil water content and solute concentration, and mini-tensiometers register matric potential. In and adjacent to the macropore-system, TDR-coil probes (diam. 0.3 cm, length of copper coil 1.5 cm) and mini-tensiometers (ceramic cup diam. 0.1-0.2 cm) monitored macropore flow and provided information to quantify inter-region water transfer. Bromide specific electrodes measured the bromide concentration in the effluent of the macropore region and of the matrix region as well as directly inside the soil matrix. The experimental setup seems promising for analyzing basic flow and transport processes in macroporous soils. In future experimental analyses, the complexity of the macropore configuration will be systematically increased in terms of macropore number, geometry, continuity, and physical properties of macropore walls.

  2. Converted charter plane for mass transport of patients after a tsunami.

    PubMed

    Björnsson, Hjalti Már; Kristjánsson, Már; Möller, Alma D

    2008-01-01

    After a tsunami in the Indian Ocean in December 2004, thousands of injured tourists were stranded far away from home. To transport injured Scandinavians and their relatives back to Sweden, a standard Icelandic charter plane was altered for the mission in 2 days. Orthopedic injuries and aspirations were the predominant injuries among patients transported, but all had received advanced care in Thailand. The transport to Sweden was uneventful. The possibility of including charter planes in plans for mass transport of injured patients in disaster preparedness is stressed. For a given incident, a detailed checklist can facilitate gathering vital information to ensure adequate equipment and patient care. The lessons from the preparation of the plane and the mission are reported.

  3. Converted charter plane for mass transport of patients after a tsunami.

    PubMed

    Björnsson, Hjalti Már; Kristjánsson, Már; Möller, Alma D

    2008-01-01

    After a tsunami in the Indian Ocean in December 2004, thousands of injured tourists were stranded far away from home. To transport injured Scandinavians and their relatives back to Sweden, a standard Icelandic charter plane was altered for the mission in 2 days. Orthopedic injuries and aspirations were the predominant injuries among patients transported, but all had received advanced care in Thailand. The transport to Sweden was uneventful. The possibility of including charter planes in plans for mass transport of injured patients in disaster preparedness is stressed. For a given incident, a detailed checklist can facilitate gathering vital information to ensure adequate equipment and patient care. The lessons from the preparation of the plane and the mission are reported. PMID:18992689

  4. Resonance ionization mass spectrometry for isotopic abundance measurements

    NASA Technical Reports Server (NTRS)

    Miller, C. M.

    1986-01-01

    Resonance ionization mass spectrometry (RIMS) is a relatively new laser-based technique for the determination of isotopic abundances. The resonance ionization process depends upon the stepwise absorption of photons from the laser, promoting atoms of the element of interest through progressively higher electronic states until an ion is formed. Sensitivity arises from the efficiency of the resonant absorption process when coupled with the power available from commercial laser sources. Selectivity derives naturally from the distinct electronic structure of different elements. This isobaric discrimination has provided the major impetus for development of the technique. Resonance ionization mass spectrometry was used for analysis of the isotopic abundances of the rare earth lutetium. Isobaric interferences from ytterbium severely effect the ability to measure small amounts of the neutron-deficient Lu isotopes by conventional mass spectrometric techniques. Resonance ionization for lutetium is performed using a continuous-wave laser operating at 452 nm, through a sequential two-photon process, with one photon exciting the intermediate resonance and the second photon causing ionization. Ion yields for microgram-sized quantities of lutetium lie between 10(6) and 10(7) ions per second, at overall ionization efficiencies approaching 10(-4). Discrimination factors against ytterbium greater than 10(6) have been measured. Resonance ionization for technetium is also being explored, again in response to an isobaric interference, molybdenum. Because of the relatively high ionization potential for Tc, three-photon, two-color RIMS processes are being developed.

  5. Precision measurement of the {Sigma}{sup 0} hyperon mass

    SciTech Connect

    Wang, M.H.L.S.; Hartouni, E.P.; Kreisler, M.N.

    1998-02-17

    The research that is described in this paper is part of a program to study strong interaction mechanisms in proton proton collisions. The program consists of two experiments: Brookhaven E766 in which we studied the reactions pp {yields} p+ all charged particles with 27.5 GeV/c incident protons and Fermilab E690 in which we studied the reactions pp {yields} p+ all charged particles with 800 GeV/c incident protons. In these experiments, we employed state-of-the-art data acquisition sys- tems and acquired large samples of data: at Brookhaven we amassed 300 million high multiplicity events and at Fermilab, 5.5 billion events. Our uncertainty in the {Sigma}{sup 0} mass is more than 7 times smaller than the best previous result and was based on 16 times the statistics. Likewise, the {Sigma}{sup 0} - {Lambda}{sup 0} mass difference is more than 14 times more accurate than the previous best result. Finally, we note that this measurement is the first direct measurement of the {Sigma}{sup 0} mass.

  6. Results of precision mass measurements from CARIBU with the CPT

    NASA Astrophysics Data System (ADS)

    van Schelt, J.; Lascar, D.; Savard, G.; Clark, J. A.; Greene, J. P.; Levand, A. F.; Sun, T.; Zabransky, B. J.; Caldwell, S.; Sternberg, M. G.; Chaudhuri, A.; Sharma, K. S.; Li, G.

    2011-10-01

    An array of neutron-rich nuclides from the CAlifornium Rare Isotope Breeder Upgrade (CARIBU) at ANL beyond 132Sn has been subjected to precision mass measurements with the Canadian Penning Trap mass spectrometer, including many never-before-measured nuclides. Neutron-separation energies calculated directly from these results provide essential input to models of the astrophysical r-process. Trends in binding energies far from stability provide input to nuclear mass models and identify regions of deformation. Additional nuclear structure information can be extracted from symmetry energy and observations of isomeric states. Implications for all of these topics will be discussed as well as future plans with the more intense CARIBU source. This work performed under the auspices of NSERC, Canada, application number 216974, and the U.S. DOE, Office of Nuclear Physics, under Contract Nos. DE-AC02- 06CH11357, DE-FG02-91ER-40609, DE-FG02-98ER41086 and DE-AC52-07NA27344.

  7. Charged Kaon Mass Measurement using the Cherenkov Effect

    SciTech Connect

    Graf, N.; Lebedev, A.; Abrams, R.J.; Akgun, U.; Aydin, G.; Baker, W.; Barnes, P.D., Jr.; Bergfeld, T.; Beverly, L.; Bujak, A.; Carey, D.; /Fermilab /Virginia U. /Iowa U.

    2009-09-01

    The two most recent and precise measurements of the charged kaon mass use X-rays from kaonic atoms and report uncertainties of 14 ppm and 22 ppm yet differ from each other by 122 ppm. We describe the possibility of an independent mass measurement using the measurement of Cherenkov light from a narrow-band beam of kaons, pions, and protons. This technique was demonstrated using data taken opportunistically by the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory which recorded beams of protons, kaons, and pions ranging in momentum from +37 GeV/c to +63 GeV/c. The measured value is 491.3 {+-} 1.7 MeV/c{sup 2}, which is within 1.4{sigma} of the world average. An improvement of two orders of magnitude in precision would make this technique useful for resolving the ambiguity in the X-ray data and may be achievable in a dedicated experiment.

  8. Deducing high-altitude precipitation from glacier mass balance measurements

    NASA Astrophysics Data System (ADS)

    Giesen, Rianne H.; Immerzeel, Walter W.; Wanders, Niko

    2016-04-01

    The spatial distribution of precipitation in mountainous terrain is generally not well known due to underrepresentation of gauge observations at higher elevations. Precipitation tends to increase with elevation, but since observations are mainly performed in the valleys, the vertical precipitation gradient cannot be deduced from these measurements. Furthermore, the spatial resolution of gridded meteorological data is often too coarse to resolve individual mountain chains. Still, a reliable estimate of high-elevation precipitation is required for many hydrological applications. We present a method to determine the vertical precipitation gradient in mountainous terrain, making use of glacier mass balance observations. These measurements have the advantage that they provide a basin-wide precipitation estimate at high elevations. The precipitation gradient is adjusted until the solid precipitation over the glacier area combined with the calculated melt gives the measured annual glacier mass balance. Results for the glacierized regions in Central Europe and Scandinavia reveal spatially coherent patterns, with predominantly positive precipitation gradients ranging from -4 to +28 % (100 m)‑1. In some regions, precipitation amounts at high elevations are up to four times as large as in the valleys. A comparison of the modelled winter precipitation with observed snow accumulation on glaciers shows a good agreement. Precipitation measured at the few high-altitude meteorological stations is generally lower than our estimate, which may result from precipitation undercatch. Our findings will improve the precipitation forcing for glacier modelling and hydrological studies in mountainous terrain.

  9. a Cylindrical Mirror Analyser for Neutrino Mass Measurement.

    NASA Astrophysics Data System (ADS)

    Williams, Simon Shaughan

    Available from UMI in association with The British Library. Requires signed TDF. The design of an electrostatic Cylindrical Mirror Analyser (CMA) for neutrino mass measurement is given. The resolution is 15 eV FWHM, being achieved with second order focusing and tight collimation. The field-matching grids are unique, being sets of accurately positioned vertical wires producing negligible resolution effects. Luminosity is maximised with an extended source and by utilisation of the full 2pi of the CMA. Background is minimised as the deflecting voltage is half the analysing energy so that field--emission can be discriminated against. Cosmic -ray secondaries are largely removed by high resolution silicon surface barrier detectors. The construction of the CMA to an accuracy of ~10 eV in base resolution, and of the magnetic shielding and vacuum systems is outlined. The power supplies and monitoring systems, signal processing electronics and data acquisition software are also described. Ytterbium conversion electron measurements confirm the calculated CMA optical resolution function to better than 10% in half-width. These measurements demonstrate that the CMA calibration and dispersion are at their theoretical values and also identify a small mis-alignment in the CMA, consistent with construction accuracy. Correcting fields are subsequently designed. The end-point spectrum of tritium is measured using a Langmuir-Blodgett mono-layer source, yielding a neutrino mass limit of <64 eV (90% CL), including total resolution systematic error and being limited principally by statistical errors. Tritium measurements also verify the luminosity of the CMA as ~ 9 times 10^ {-4} cm^2 and demonstrate the extremely low background of 2 times 10^{-3} s^{-1} . Monte-Carlo simulations indicate that with this optical resolution, knowledge of molecular final states and energy loss, a lower limit of 10 eV (95% CL) should be measured for a neutrino mass of 30 eV with a suitable source. For a zero

  10. Transportable IOT measurement station for direct-broadcast satellites

    NASA Astrophysics Data System (ADS)

    Ulbricht, Michael

    A transportable 11.7-12.5-GHz flux-density measurement facility for use in the in-orbit testing (IOT) of the FRG TV-Sat direct-broadcast satellites is described. Major components include a 1.2-m-diameter antenna, the fluxmeter, a radiometer to determine atmospheric attenuation, a weather station, and a control and data-processing computer; all of the components are mounted on a 5.10 x 2.35 x 2.70-m trailer. IOT performance parameters include gain/temperature ratio 15.9 dB/K, measurement range -97 to -117 dBW/sq m, measurement accuracy less than 0.5 dB rms, and measurement rate 250-650 msec. Photographs and a block diagram are provided.

  11. Reporting and measurement of mass-dependent and mass-independent fractionation of mercury isotopes

    NASA Astrophysics Data System (ADS)

    Bergquist, B. A.; Blum, J. D.

    2007-12-01

    Hg isotope analysis by MC-ICP-MS is an important new approach for fingerprinting Hg sources and monitoring Hg redox reactions and bioaccumulation, especially with the recent discovery of mass independent Hg isotope fractionation. Unfortunately research groups have adopted different standards, definitions of delta values, and methods of isotopic measurement. We suggest that a single standard, NIST SRM 3133, be adopted for reporting the isotopic variability of Hg isotopes. Isotope ratios should be determined by sample-standard bracketing (SSB) during analysis and reported as permil (‰) deviation from SRM 3133. For the highest precision and accuracy, a Tl internal standard along with SSB should be used to correct instrumental mass bias. Measurement routines should also include on-peak zero corrections and matching of concentration and matrix between the samples and bracketing standard. For samples that display mass-dependent fractionation (MDF), only one delta value needs to be reported (δ202/198Hg). Mass-independent fractionation (MIF) (Jackson et al., 2006; Bergquist et al., 2006; Bergquist and Blum, submitted) requires additional nomenclature, and we suggest reporting MIF as the deviation in isotope ratios from the theoretical mass dependent kinetic isotope fractionation (Δxxx/198Hg)¬. External reproducibility should be monitored by analysis of secondary standards. For studies of MDF, we use an in-house secondary standard solution made from metallic Hg mined from Almaden Spain and obtain a δ202Hg of -0.55 ±0.06‰ (2SD). For studies of MIF, we use NRCC CRM DORM-2 (dogfish muscle) and obtain a mean value of δ202Hg of +0.19 ±0.13‰ (2SD), Δ201Hg of +0.89 ±0.07‰ (2SD) , and Δ199Hg of +1.07 ±0.08‰ (2SD).

  12. High-Precision Mass Measurements At TRIGA-TRAP

    NASA Astrophysics Data System (ADS)

    Smorra, C.; Beyer, T.; Blaum, K.; Block, M.; Eberhardt, K.; Eibach, M.; Herfurth, F.; Ketelaer, J.; Knuth, K.; Nörtershäuser, W.; Nagy, Sz.

    2010-04-01

    In order to study neutron-rich nuclides far from the valley of stability as well as long-lived actinoids the double Penning-trap mass spectrometer TRIGA-TRAP has been recently installed at the research reactor TRIGA Mainz. Short-lived neutron-rich fission products are produced by thermal neutron-induced fission of an actinoid target installed close to the reactor core. A helium gas-jet system with carbon aerosol particles is used to extract the fission products to the experiment. The Penning trap system has already been commissioned. Off-line mass measurements are routinely performed using a recently developed laser ablation ion source, and the gas-jet system has been tested. An overview of the experiment and current status will be given.

  13. Can we measure the neutrino mass hierarchy in the sky?

    SciTech Connect

    Jimenez, Raul; Verde, Licia; Kitching, Thomas; Peña-Garay, Carlos E-mail: tdk@roe.ac.uk E-mail: liciaverde@icc.ub.edu

    2010-05-01

    Cosmological probes are steadily reducing the total neutrino mass window, resulting in constraints on the neutrino-mass degeneracy as the most significant outcome. In this work we explore the discovery potential of cosmological probes to constrain the neutrino hierarchy, and point out some subtleties that could yield spurious claims of detection. This has an important implication for next generation of double beta decay experiments, that will be able to achieve a positive signal in the case of degenerate or inverted hierarchy of Majorana neutrinos. We find that cosmological experiments that nearly cover the whole sky could in principle distinguish the neutrino hierarchy by yielding 'substantial' evidence for one scenario over the another, via precise measurements of the shape of the matter power spectrum from large scale structure and weak gravitational lensing.

  14. Measuring Neutrino Mass with Radioactive Ions in a Storage Ring

    SciTech Connect

    Lindroos, Mats; McElrath, Bob; Orme, Christopher; Schwetz, Thomas

    2010-03-30

    A method to measure the neutrino mass kinematically using beams of ions which undergo beta decay is proposed. The idea is to tune the ion beam momentum so that in most decays, the electron is forward moving with respect to the beam, and only in decays near the endpoint is the electron moving backwards. By counting the backward moving electrons one can observe the effect of neutrino mass on the beta spectrum close to the endpoint. In order to reach sensitivities for m{sub n}u<0.2 eV, it is necessary to control the ion momentum with a precision better than deltap/p<10{sup -5}, identify suitable nuclei with low Q-values (in the few to ten keV range), and one must be able to observe at least O(10{sup 18}) decays.

  15. Measuring neutrino mass with radioactive ions in a storage ring

    NASA Astrophysics Data System (ADS)

    Lindroos, Mats; McElrath, Bob; Orme, Christopher; Schwetz, Thomas

    2009-12-01

    We propose a method to measure the neutrino mass kinematically using beams of ions which undergo beta decay. The idea is to tune the ion beam momentum so that in most decays, the electron is forward moving with respect to the beam, and only in decays near the endpoint is the electron moving backwards. Then, by counting the backward moving electrons one can observe the effect of neutrino mass on the beta spectrum close to the endpoint. In order to reach sensitivities for m ν <0.2 eV, it is necessary to control the ion momentum with a precision better than δ p/ p<10-5, identify suitable nuclei with low Q-values (in the few to ten keV range), and one must be able to observe at least mathcal{O}(10^{18}) decays.

  16. Measuring neutrino mass with radioactive ions in a storage ring

    NASA Astrophysics Data System (ADS)

    Lindroos, Mats; McElrath, Bob; Orme, Christopher; Schwetz, Thomas

    2010-01-01

    We propose a method to measure the neutrino mass kinematically using beams of ions which undergo beta decay. The idea is to tune the ion beam momentum so that in most decays, the electron is forward moving with respect to the beam, and only in decays near the endpoint is the electron moving backwards. Then, by counting the backward moving electrons one can observe the effect of neutrino mass on the beta spectrum close to the endpoint. In order to reach sensitivities for mν < 0.2 eV, it is necessary to control the ion momentum with a precision better than δp/p < 10-5, identify suitable nuclei with low Q-values (in the few to ten keV range), and one must be able to observe at least Script O(1018) decays.

  17. Measuring Neutrino Mass with Radioactive Ions in a Storage Ring

    NASA Astrophysics Data System (ADS)

    Lindroos, Mats; McElrath, Bob; Orme, Christopher; Schwetz, Thomas

    2010-03-01

    A method to measure the neutrino mass kinematically using beams of ions which undergo beta decay is proposed. The idea is to tune the ion beam momentum so that in most decays, the electron is forward moving with respect to the beam, and only in decays near the endpoint is the electron moving backwards. By counting the backward moving electrons one can observe the effect of neutrino mass on the beta spectrum close to the endpoint. In order to reach sensitivities for mν<0.2 eV, it is necessary to control the ion momentum with a precision better than δp/p<10-5, identify suitable nuclei with low Q-values (in the few to ten keV range), and one must be able to observe at least O(1018) decays.

  18. Top mass measurements at the Tevatron run II

    SciTech Connect

    Velev, Gueorgui V.; /Fermilab

    2005-10-01

    The latest top quark mass measurements by the CDF and D0 experiments are presented here. The mass has been determined in the dilepton (t{bar t} {yields} e{mu}, ee, {mu}{mu} + jets + E{sub T}) and lepton plus jets (t{bar t} {yields} e or {mu} + jets + E{sub T}) final states. The most accurate single result from lepton plus jets channel is 173.5{sub -3.6}{sup +3.7}(stat. + Jet Energy Scale Systematic) {+-} 1.3(syst.) GeV/c{sup 2}, which is better than the combined CDF and D0 Run I average. A preliminary and unofficial average of the best experimental Run II results gives M{sub top} = 172.7 {+-} 3.5 GeV/c{sup 2}.

  19. Specific features of defect and mass transport in concentrated fcc alloys

    DOE PAGES

    Osetsky, Yuri N.; Béland, Laurent K.; Stoller, Roger E.

    2016-06-15

    We report that diffusion and mass transport are basic properties that control materials performance, such as phase stability, solute decomposition and radiation tolerance. While understanding diffusion in dilute alloys is a mature field, concentrated alloys are much less studied. Here, atomic-scale diffusion and mass transport via vacancies and interstitial atoms are compared in fcc Ni, Fe and equiatomic Ni-Fe alloy. High temperature properties were determined using conventional molecular dynamics on the microsecond timescale, whereas the kinetic activation-relaxation (k-ART) approach was applied at low temperatures. The k-ART was also used to calculate transition states in the alloy and defect transport coefficients.more » The calculations reveal several specific features. For example, vacancy and interstitial defects migrate via different alloy components, diffusion is more sluggish in the alloy and, notably, mass transport in the concentrated alloy cannot be predicted on the basis of diffusion in its pure metal counterparts. Lastly, the percolation threshold for the defect diffusion in the alloy is discussed and it is suggested that this phenomenon depends on the properties and diffusion mechanisms of specific defects.« less

  20. Mass composition measurements at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Molina Bueno, L.; Pierre Auger Collaboration

    2015-11-01

    The Pierre Auger Observatory is the largest ultra-high energy cosmic ray experiment built so far. It is a hybrid detector, since it measures both the fluorescence light emitted while the air showers develop in the atmosphere and the particles reaching the ground. We present the results related to the mass composition of ultra-high energy cosmic rays as obtained from both types of measurements. The depth at which the maximum of the electromagnetic development takes place and its fluctuations are the most sensitive parameters to infer the nature of the cosmic rays. In addition, we present the latest muon measurements that can be used to test and constrain models of hadronic interactions at energies larger than those reached at LHC.

  1. Mass Transport and Shear Stress as Mediators of Flow Effects on Atherosclerotic Plaque Origin and Growth

    NASA Astrophysics Data System (ADS)

    Gorder, Riley; Aliseda, Alberto

    2009-11-01

    The carotid artery bifurcation (CAB) is one of the leading site for atherosclerosis, a major cause of mortality and morbidity in the developed world. The specific mechanisms by which perturbed flow at the bifurcation and in the carotid bulge promotes plaque formation and growth are not fully understood. Shear stress, mass transport, and flow residence times are considered dominant factors. Shear stress causes restructuring of endothelial cells at the arterial wall which changes the wall's permeability. Long residence times are associated with enhanced mass transport through increased diffusion of lipids and white blood cells into the arterial wall. Although momentum and mass transfer are traditionally coupled by correlations similar to Reynolds Analogy, the complex flow patterns present in this region due to the pulsatile, transitional, detached flow associated with the complex geometry makes the validity of commonly accepted assumptions uncertain. We create solid models of the CAB from MRI or ultrasound medical images, build flow phantoms on clear polyester resin and use an IOR matching, blood mimicking, working fluid. Using PIV and dye injection techniques the shear stress and scalar transport are experimentally investigated. Our goal is to establish a quantitative relationship between momentum and mass transfer under a wide range of physiologically normal and pathological conditions.

  2. Implications of anthropogenic river stage fluctuations on mass transport in a valley fill aquifer

    USGS Publications Warehouse

    Boutt, D.F.; Fleming, B.J.

    2009-01-01

    In humid regions a strong coupling between surface water features and groundwater systems may exist. In these environments the exchange of water and solute depends primarily on the hydraulic gradient between the reservoirs. We hypothesize that daily changes in river stage associated with anthropogenic water releases (such as those from a hydroelectric dam) cause anomalous mixing in the near-stream environment by creating large hydraulic head gradients between the stream and adjacent aquifer. We present field observations of hydraulic gradient reversals in a shallow aquifer. Important physical processes observed in the field are explicitly reproduced in a physically based two-dimensional numerical model of groundwater flow coupled to a simplistic surface water boundary condition. Mass transport simulations of a conservative solute introduced into the surface water are performed and examined relative to a stream condition without stage fluctuations. Simulations of 20 d for both fluctuating river stage and fixed high river stage show that more mass is introduced into the aquifer from the stream in the oscillating case even though the net water flux is zero. Enhanced transport by mechanical dispersion leads to mass being driven away from the hydraulic zone of influence of the river. The modification of local hydraulic gradients is likely to be important for understanding dissolved mass transport in near-stream aquifer environments and can influence exchange zone processes under conditions of high-frequency stream stage changes. Copyright 2009 by the American Geophysical Union.

  3. A PRECISE MASS MEASUREMENT OF THE INTERMEDIATE-MASS BINARY PULSAR PSR J1802 - 2124

    SciTech Connect

    Ferdman, R. D.; Cognard, I.; Desvignes, G.; Theureau, G.; Stairs, I. H.; Kramer, M.; McLaughlin, M. A.; Lorimer, D. R.; Nice, D. J.; Manchester, R. N.; Hobbs, G.; Lyne, A. G.; Faulkner, A.; Camilo, F.; Possenti, A.; Demorest, P. B.; Backer, D. C.

    2010-03-10

    PSR J1802 - 2124 is a 12.6 ms pulsar in a 16.8 hr binary orbit with a relatively massive white dwarf (WD) companion. These properties make it a member of the intermediate-mass class of binary pulsar (IMBP) systems. We have been timing this pulsar since its discovery in 2002. Concentrated observations at the Green Bank Telescope, augmented with data from the Parkes and Nancay observatories, have allowed us to determine the general relativistic Shapiro delay. This has yielded pulsar and WD mass measurements of 1.24 +- 0.11 M{sub sun} and 0.78 +- 0.04 M{sub sun} (68% confidence), respectively. The low mass of the pulsar, the high mass of the WD companion, the short orbital period, and the pulsar spin period may be explained by the system having gone through a common-envelope phase in its evolution. We argue that selection effects may contribute to the relatively small number of known IMBPs.

  4. Measuring the neutrino mass from future wide galaxy cluster catalogues

    SciTech Connect

    Carbone, Carmelita; Moscardini, Lauro; Cimatti, Andrea; Fedeli, Cosimo E-mail: cosimo.fedeli@astro.ufl.edu E-mail: a.cimatti@unibo.it

    2012-03-01

    We present forecast errors on a wide range of cosmological parameters obtained from a photometric cluster catalogue of a future wide-field Euclid-like survey. We focus in particular on the total neutrino mass as constrained by a combination of the galaxy cluster number counts and correlation function. For the latter we consider only the shape information and the Baryon Acoustic Oscillations (BAO), while marginalising over the spectral amplitude and the redshift space distortions. In addition to the cosmological parameters of the standard ΛCDM+ν model we also consider a non-vanishing curvature, and two parameters describing a redshift evolution for the dark energy equation of state. For completeness, we also marginalise over a set of ''nuisance'' parameters, representing the uncertainties on the cluster mass determination. We find that combining cluster counts with power spectrum information greatly improves the constraining power of each probe taken individually, with errors on cosmological parameters being reduced by up to an order of magnitude. In particular, the best improvements are for the parameters defining the dynamical evolution of dark energy, where cluster counts break degeneracies. Moreover, the resulting error on neutrino mass is at the level of σ(M{sub ν}) ∼ 0.9 eV, comparable with that derived from present Lyα forest measurements and Cosmic Microwave background (CMB) data in the framework of a non-flat Universe. Further adopting Planck priors and reducing the number of free parameters to a ΛCDM+ν cosmology allows to place constraints on the total neutrino mass of σ(M{sub ν}) ∼ 0.08 eV, close to the lower bound enforced by neutrino oscillation experiments. Finally, in the optimistic case where uncertainties in the calibration of the mass-observable relation were so small to be neglected, the combination of Planck priors with cluster counts and power spectrum would constrain the total neutrino mass down to σ(M{sub ν}) ∼ 0.034 eV, i

  5. Mass transfer and transport of radionuclides through backfill in a geologic nuclear waster repository

    SciTech Connect

    Kang, Chulhyung.

    1989-01-01

    Analytical models for the mass transfer and transport of radionuclides through waste package backfill material are developed and their numerical illustrations are demonstrated. These models can aid in the performance assessment of the waste package in nuclear waste repositories. The following analyses are considered to study the performance of the backfill barrier in a geologic nuclear waste repository. (1) The analysis for time and space dependent mass transfer and mass transport of a radioactive decay chain for a congruent release with the matrix species is studied. Non-recursive analytical solutions are derived for a semi-infinite medium and a finite medium. The theory is illustrated with the important decay chain {sup 234}U {yields} {sup 230}Th {yields} {sup 226}Ra. (2) The time and space dependent mass transport for high solubility nuclides, such as iodine or cesium, is analyzed. The approximate solution that is valid for all times is developed, and validated by comparison with an asymptotic solution and the solution obtained by the numerical inversion of a Laplace transform covering the entire time span. From this model one can determine the thickness of the backfill to satisfy a prescribed release rate limit for high soluble radionuclides. (3) The analysis of the transient radionuclide migration through the backfill into a fracture intersecting the waste form is developed. The nuclides are advected by water flowing in the fracture. The numerical illustrations show that the species transport for the short half-life nuclide can be stopped effectively within the backfill, but the backfill can no longer retard the migration for stable nuclides or long half-life nuclides after some initial time period. (4) The steady state mass transfer from a cylindrical waste form with flow through the backfill layer is examined.

  6. Coupled Gravity and Elevation Measurement of Ice Sheet Mass Change

    NASA Technical Reports Server (NTRS)

    Jezek, K. C.; Baumgartner, F.

    2005-01-01

    During June 2003, we measured surface gravity at six locations about a glaciological measurement site located on the South-central Greenland Ice. We operated a GPS unit for 90 minutes at each site -the unit was operated simultaneously with a base station unit in Sondrestrom Fjord so as to enable differential, post-processing of the data. We installed an aluminum, accumulation-rate-pole at each site. The base section of the pole also served as the mount for the GPS antenna. Two gravimeters were used simultaneously at each site. Measurements were repeated at each site with at time lapse of at least 50 minutes. We measured snow physical properties in two shallow pits The same measurement sites were occupied in 1981 and all were part of a hexagonal network of geodetic and glaciological measurements established by The Ohio State University in 1980. Additional gravity observations were acquired at three of the sites in 1993 and 1995. Gravity data were collected in conjunction with Doppler satellite measurements of position and elevation in 1981 and global positioning system measurements subsequently. The use of satellite navigation techniques permitted reoccupation of the same sites in each year to within a few 10 s of meters or better. After detrending the gravity data, making adjustments for tides and removing the residual effects of local spatial gradients in gravity, we observe an average secular decrease in gravity of about 0.01 milligal/year, but with tenths of milligal variations about the mean trend. The trend is consistent with a nearly linear increase in surface elevation of between 7 to 10 c d y r (depending on location) as measured by repeated airborne laser altimeter, surface Doppler satellite and GPS elevation measurements. Differences between the residual gravity anomalies after free air correction may be attributable to local mass changes. This project is a collaboration between the Byrd Polar Research Center of the Ohio State University and the Arctic

  7. Determination of parameters of Cu surface mass transport on sapphire from morphological changes of beaded films caused by evaporation

    NASA Astrophysics Data System (ADS)

    Beszeda, I.; Beke, D. L.

    Basic parameters of surface mass transport - the surface diffusion length of adatoms, λs, the surface diffusion coefficient, Ds', and the surface reaction rate coefficient, βs', of Cu on alumina are determined in the temperature range 1048-1198 K. Measuring simultaneously the time dependence of the effective thickness, Heff(t), the lateral shift of the boundary, y(t) of beaded films (BF) and using vapour pressure data we concluded that the process is controlled by surface reaction at the perimeters of beads. Supposing Arrhenius-type temperature dependence for Ds', βs' and λs the activation energies and preexponential factors have been calculated.

  8. Plutonium measurements by accelerator mass spectrometry at LLNL

    SciTech Connect

    McAninch, J E; Hamilton, T F; Broan, T A; Jokela, T A; Knezovich, T J; Ognibene, T J; Proctor, I D; Roberts, M L; Southon, J R; Vogel, J S; Sideras-Haddad, E

    1999-10-26

    Mass spectrometric methods provide sensitive, routine, and cost-effective analyses of long-lived radionuclides. Here the authors report on the status of work at Lawrence Livermore National Laboratory (LLNL) to develop a capability for actinide measurements by accelerator mass spectrometry (AMS) to take advantage of the high potential of AMS for rejection of interferences. This work demonstrates that the LLNL AMS spectrometer is well-suited for providing high sensitivity, robust, high throughput measurements of plutonium concentrations and isotope ratios. Present backgrounds are {approximately}2 x 10{sup 7}atoms per sample for environmental samples prepared using standard alpha spectrometry protocols. Recent measurements of {sup 239+240}Pu and {sup 241}Pu activities and {sup 240}Pu/{sup 239}Pu isotope ratios in IAEA reference materials agree well with IAEA reference values and with alpha spectrometry and recently published ICP-MS results. Ongoing upgrades of the AMS spectrometer are expected to reduce backgrounds below 1 x 10{sup 6} atoms per sample while allowing simplifications of the sample preparation chemistry. These simplifications will lead to lower per-sample costs, higher throughput, faster turn around and, ultimately, to larger and more robust data sets.

  9. Measurement of the charged kaon mass with the MIPP RICH

    SciTech Connect

    Graf, Nicholas J.

    2008-08-01

    The currently accepted value of the charged kaon mass is 493.677 ± 0.013 MeV (26 ppm). It is a weighted average of six measurements, most of which use kaonic atom X-ray energy techniques. The two most recent and precise results dominate the average but differ by 122 ppm. Inconsistency in the data set needs to be resolved, preferably using independent techniques. One possibility uses the Cherenkov effect. A measurement of the charged kaon mass using this technique is presented. The data was taken with the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory using a tagged beam of protons, kaons, and pions ranging in momentum from 37 GeV/c to 63 GeV/c. The measured value is 491.3 ± 1.7 MeV. This is within 1.4σ of the current value. An improvement in precision by a factor of 35 would make this technique competitive for resolving the ambiguity in the X-ray data.

  10. Mass spectroscopic characterization of the GeSe:GeI4 vapor transport system

    NASA Technical Reports Server (NTRS)

    Buchan, Nicholas I.; Rosenberger, Franz

    1987-01-01

    The GeSe:GeI4 vapor crystal growth system was characterized mass spectroscopically. A steady-state Knudsen effusion technique was developed to simulate the equilibrium conditions at one end of a vapor transport ampoule. It was found that the previously neglected equilibrium GeSe2(s) = GeSe(v) + 1/2Se2(v) reduces the Se2(v) concentration to an extent that sublimation/condensation of GeSe becomes the dominant transport mechanism. At total pressures near 1 atm the concentration of an additional Ge-Se-I vapor species becomes comparable to that of GeSe(v).

  11. Precision measurement of top quark mass in dilepton channel

    SciTech Connect

    Jayatilaka, Bodhitha; /Michigan U.

    2006-01-01

    We present recent measurements of the top quark mass using events collected at the CDF and D0 detectors from p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron. These analyses are performed using events consistent with the decay channel t{bar t} {yields} {bar b}{ell}{sup -}{bar v}{sub {ell}}b{ell}' + v'{sub {ell}}, or the dilepton channel. 230-360 pb{sup -1} of data are used.

  12. Methods for measuring and transporting angular momentum in general relativity

    NASA Astrophysics Data System (ADS)

    Nichols, David; Flanagan, Eanna; Stein, Leo; Vines, Justin

    2016-03-01

    For an observer in a curved spacetime, elements of the dual space of the set of linearized Poincare transformations from the observer's tangent space to itself can naturally be interpreted as local linear and angular momenta. We give an operational procedure by which the observer can measure such local linear and angular momenta from the local spacetime geometry. These momenta can be interpreted as approximate versions of the linear and angular momenta of the spacetime about the observer's location. The measurement algorithm allows for a more accurate determination of the linear and angular momentum of stationary, asymptotically flat systems than previous proposals do. We also describe a prescription by which observers at different locations can compare values of their measured linear and angular momentum by using a specific transport equation, which refines previous proposals. These operational definitions may also prove useful for clarifying the physical interpretation of Bondi-Metzner-Sachs asymptotic charges in asymptotically flat spacetimes.

  13. Mass transport and organic matter distribution in paleoceanographic reconstruction of the northern Arabian Platform during the Early Cretaceous

    NASA Astrophysics Data System (ADS)

    Bialik, Or; Waldmann, Nicolas

    2016-04-01

    The Barremian-Aptian sedimentary succession in the Western Levant is an important reservoir strata notably due to intercalation of carbonates and coarse siliciclastics. In much of the northern Levant this strata has been described as a transition from siliciclastic marginal marine deposits to carbonate shoals and lagoons - posing the possibility of similar configurations. Results from high-resolution elemental, mineralogical, sedimentological and petrophysical analyses measured on a set of long cores from northern Israel offers a unique look at this transition, in terms of the paleoceanography, geometry and ventilation conditions in the lead-up to Oceanic Anoxic Events 1a and 1b. Two intervals of abundant mass-transport deposits (MTDs) emplacement were identified in this succession: a Late Barremian series and an Aptian series. These MTDs are graded and/or chaotic, they significantly differ from the fine grained, fine laminated calcareous shale in-situ lithology. The background lithology was found to contain elevated organic matter, sulfur and iron content while bioturbation features are notably scarce or absent. At the contacts between the marine shales and the MTDs, there is a decrease in sulfur and iron, indicating more oxic conditions at the sediment-water interface of the emplaced units, compounded by a coeval oxygenation of the native deeper waters due to turbulence and mixing associated with mass transport. Together, these observations indicate emplacement of coarse-grained, shallow water MTDs at the lower termination of a slope, with gradient sufficient to support mass transport above a basal shear plane. The lithologies within the MTDs indicate high energy downslope transport of calcareous and terrestrial material into a low-energy basinal environment during the Late Barremian and Aptian. These background sediments bear evidence suggestive of at least two intervals of diminished oxygen in the lower water column, one predating OAE 1.

  14. Hysteresis in Transport Critical-Current Measurements of Oxide Superconductors

    PubMed Central

    Goodrich, L. F.; Stauffer, T. C.

    2001-01-01

    We have investigated magnetic hysteresis in transport critical-current (Ic) measurements of Ag-matrix (Bi,Pb)2Sr2Ca2Cu3O10–x (Bi-2223) and AgMg-matrix Bi2Sr2CaCu2O8+x (Bi-2212) tapes. The effect of magnetic hysteresis on the measured critical current of high temperature superconductors is a very important consideration for every measurement procedure that involves more than one sweep of magnetic field, changes in field angle, or changes in temperature at a given field. The existence of this hysteresis is well known; however, the implications for a measurement standard or interlaboratory comparisons are often ignored and the measurements are often made in the most expedient way. A key finding is that Ic at a given angle, determined by sweeping the angles in a given magnetic field, can be 17 % different from the Ic determined after the angle was fixed in zero field and the magnet then ramped to the given field. Which value is correct is addressed in the context that the proper sequence of measurement conditions reflects the application conditions. The hysteresis in angle-sweep and temperature-sweep data is related to the hysteresis observed when the field is swept up and down at constant angle and temperature. The necessity of heating a specimen to near its transition temperature to reset it to an initial state between measurements at different angles and temperatures is discussed. PMID:27500042

  15. Effects of reservoir heterogeneity on scaling of effective mass transfer coefficient for solute transport.

    PubMed

    Leung, Juliana Y; Srinivasan, Sanjay

    2016-09-01

    Modeling transport process at large scale requires proper scale-up of subsurface heterogeneity and an understanding of its interaction with the underlying transport mechanisms. A technique based on volume averaging is applied to quantitatively assess the scaling characteristics of effective mass transfer coefficient in heterogeneous reservoir models. The effective mass transfer coefficient represents the combined contribution from diffusion and dispersion to the transport of non-reactive solute particles within a fluid phase. Although treatment of transport problems with the volume averaging technique has been published in the past, application to geological systems exhibiting realistic spatial variability remains a challenge. Previously, the authors developed a new procedure where results from a fine-scale numerical flow simulation reflecting the full physics of the transport process albeit over a sub-volume of the reservoir are integrated with the volume averaging technique to provide effective description of transport properties. The procedure is extended such that spatial averaging is performed at the local-heterogeneity scale. In this paper, the transport of a passive (non-reactive) solute is simulated on multiple reservoir models exhibiting different patterns of heterogeneities, and the scaling behavior of effective mass transfer coefficient (Keff) is examined and compared. One such set of models exhibit power-law (fractal) characteristics, and the variability of dispersion and Keff with scale is in good agreement with analytical expressions described in the literature. This work offers an insight into the impacts of heterogeneity on the scaling of effective transport parameters. A key finding is that spatial heterogeneity models with similar univariate and bivariate statistics may exhibit different scaling characteristics because of the influence of higher order statistics. More mixing is observed in the channelized models with higher-order continuity. It

  16. Effects of reservoir heterogeneity on scaling of effective mass transfer coefficient for solute transport

    NASA Astrophysics Data System (ADS)

    Leung, Juliana Y.; Srinivasan, Sanjay

    2016-09-01

    Modeling transport process at large scale requires proper scale-up of subsurface heterogeneity and an understanding of its interaction with the underlying transport mechanisms. A technique based on volume averaging is applied to quantitatively assess the scaling characteristics of effective mass transfer coefficient in heterogeneous reservoir models. The effective mass transfer coefficient represents the combined contribution from diffusion and dispersion to the transport of non-reactive solute particles within a fluid phase. Although treatment of transport problems with the volume averaging technique has been published in the past, application to geological systems exhibiting realistic spatial variability remains a challenge. Previously, the authors developed a new procedure where results from a fine-scale numerical flow simulation reflecting the full physics of the transport process albeit over a sub-volume of the reservoir are integrated with the volume averaging technique to provide effective description of transport properties. The procedure is extended such that spatial averaging is performed at the local-heterogeneity scale. In this paper, the transport of a passive (non-reactive) solute is simulated on multiple reservoir models exhibiting different patterns of heterogeneities, and the scaling behavior of effective mass transfer coefficient (Keff) is examined and compared. One such set of models exhibit power-law (fractal) characteristics, and the variability of dispersion and Keff with scale is in good agreement with analytical expressions described in the literature. This work offers an insight into the impacts of heterogeneity on the scaling of effective transport parameters. A key finding is that spatial heterogeneity models with similar univariate and bivariate statistics may exhibit different scaling characteristics because of the influence of higher order statistics. More mixing is observed in the channelized models with higher-order continuity. It

  17. Effects of reservoir heterogeneity on scaling of effective mass transfer coefficient for solute transport.

    PubMed

    Leung, Juliana Y; Srinivasan, Sanjay

    2016-09-01

    Modeling transport process at large scale requires proper scale-up of subsurface heterogeneity and an understanding of its interaction with the underlying transport mechanisms. A technique based on volume averaging is applied to quantitatively assess the scaling characteristics of effective mass transfer coefficient in heterogeneous reservoir models. The effective mass transfer coefficient represents the combined contribution from diffusion and dispersion to the transport of non-reactive solute particles within a fluid phase. Although treatment of transport problems with the volume averaging technique has been published in the past, application to geological systems exhibiting realistic spatial variability remains a challenge. Previously, the authors developed a new procedure where results from a fine-scale numerical flow simulation reflecting the full physics of the transport process albeit over a sub-volume of the reservoir are integrated with the volume averaging technique to provide effective description of transport properties. The procedure is extended such that spatial averaging is performed at the local-heterogeneity scale. In this paper, the transport of a passive (non-reactive) solute is simulated on multiple reservoir models exhibiting different patterns of heterogeneities, and the scaling behavior of effective mass transfer coefficient (Keff) is examined and compared. One such set of models exhibit power-law (fractal) characteristics, and the variability of dispersion and Keff with scale is in good agreement with analytical expressions described in the literature. This work offers an insight into the impacts of heterogeneity on the scaling of effective transport parameters. A key finding is that spatial heterogeneity models with similar univariate and bivariate statistics may exhibit different scaling characteristics because of the influence of higher order statistics. More mixing is observed in the channelized models with higher-order continuity. It

  18. Advances in Studies of Electrode Kinetics and Mass Transport in AMTEC Cells (abstract)

    NASA Technical Reports Server (NTRS)

    Williams, R. M.; Jeffries-Nakamura, B.; Ryan, M. A.; Underwood, M. L.; Kisor, A.; O'Connor, D.; Kikkert, S.

    1993-01-01

    Previous work reported from JPL has included characterization of electrode kinetics and alkali atom transport from electrodes including Mo, W, WRh(sub x), WPt(sub x)(Mn), in sodium AMTEC cells and vapor exposure cells, and Mo in potassium vapor exposure cells. These studies were generally performed in cells with small area electrodes (about 1 to 5 cm(sup 2)), and device geometry had little effect on transport. Alkali diffusion coefficients through these electrodes have been characterized, and approximate surface diffusion coefficients derived in cases of activated transport. A basic model of electrode kinetic at the alkali metal vapor/porous metal electrode/alkali beta'-alumina solid electrolyte three phase boundary has been proposed which accounts for electrochemical reaction rates with a collision frequency near the three phase boundary and tunneling from the porous electrode partially covered with adsorbed alkali metal atoms. The small electrode effect in AMTEC cells has been discussed in several papers, but quantitative investigations have described only the overall effect and the important contribution of electrolyte resistance. The quantitative characterization of transport losses in cells with large area electrodes has been limited to simulations of large area electrode effects, or characterization of transport losses from large area electrodes with significant longitudinal temperature gradients. This paper describes new investigations of electrochemical kinetics and transport, particularily with WPt(sub 3.5) electrodes, including the influence of electrode size on the mass transport loss in the AMTEC cell. These electrodes possess excellent sodium transport properties making verification of device limitations on transport much more readily attained.

  19. Schwinger's Measurement Algebra, Preons and the Lepton Masses

    NASA Astrophysics Data System (ADS)

    Brannen, Carl

    2006-04-01

    In the 1950s and 1960s, Julian Schwinger developed an elegant general scheme for quantum kinematics and dynamics appropriate to systems with a finite number of dynamical variables, now knowns as ``Schwinger's Measurement Algebra'' (SMA). The SMA has seen little use, largely because it is non relativistic in that it does not allow for particle creation. In this paper, we apply the SMA to the problem of modeling tightly bound subparticles (preons) of the leptons and quarks. We discuss the structure of the ideals of Clifford algebras and, applying this to the elementary fermions, derive a preon substructure for the quarks and leptons. We show that matrices of SMA type elements can be used to model the quarks and leptons under the assumption that the preons are of such high energy that they cannot be created in normal interactions. This gives a definition of the SMA for the composite particle in terms of the SMA of its constituents. We solve the resulting matrix equation for the quarks and leptons. We show that the mass operator for the charged leptons is related to the democratic mass matrix used in the Koide mass formula.

  20. Nanoscale Electron Transport Measurements of Immobilized Cytochrome P450 Proteins

    PubMed Central

    Bostick, Christopher D.; Flora, Darcy R.; Gannett, Peter M.; Tracy, Timothy S.; Lederman, David

    2015-01-01

    Gold nanopillars, functionalized with an organic self-assembled monolayer, can be used to measure the electrical conductance properties of immobilized proteins without aggregation. Measurements of the conductance of nanopillars with cytochrome P450 2C9 (CYP2C9) proteins using conducting probe atomic force microscopy demonstrate that a correlation exists between the energy barrier height between hopping sites and CYP2C9 metabolic activity. Measurements performed as a function of tip force indicate that, when subjected to a large force, the protein is more stable in the presence of a substrate. This agrees with the hypothesis that substrate entry into the active site helps to stabilize the enzyme. The relative distance between hopping sites also increases with increasing force, possibly because protein functional groups responsible for electron transport depend on the structure of the protein. The inhibitor sulfaphenazole, in addition to the previously studied aniline, increased the barrier height for electron transfer and thereby makes CYP2C9 reduction more difficult and inhibits metabolism. This suggests that P450 Type II binders may decrease the ease of electron transport processes in the enzyme, in addition to occupying the active site. PMID:25804257

  1. Gluon transport equation with effective mass and dynamical onset of Bose–Einstein condensation

    DOE PAGES

    Blaizot, Jean-Paul; Jiang, Yin; Liao, Jinfeng

    2016-05-01

    In this paper we study the transport equation describing a dense system of gluons, in the small scattering angle approximation, taking into account medium-generated effective masses of the gluons. We focus on the case of overpopulated systems that are driven to Bose–Einstein condensation on their way to thermalization. Lastly, the presence of a mass modifies the dispersion relation of the gluon, as compared to the massless case, but it is shown that this does not change qualitatively the scaling behavior in the vicinity of the onset.

  2. LETTER: Construction of the factorized steady state distribution in models of mass transport

    NASA Astrophysics Data System (ADS)

    Zia, R. K. P.; Evans, M. R.; Majumdar, Satya N.

    2004-10-01

    For a class of one-dimensional mass transport models we present a simple and direct test on the chipping functions, which define the probabilities for mass to be transferred to neighbouring sites, to determine whether the stationary distribution is factorized. In cases where the answer is affirmative, we provide an explicit method for constructing the single-site weight function. As an illustration of the power of this approach, previously known results on the zero-range process and asymmetric random average process are recovered in a few lines. We also construct new models, namely a generalized zero-range process and a binomial chipping model, which have factorized steady states.

  3. Technologies involved in configuring an advanced earth-to-orbit transport for low structural mass

    NASA Technical Reports Server (NTRS)

    Macconochie, I. O.; Klich, P. J.

    1980-01-01

    A tradeoff study for a single-stage, earth-to-orbit transport spacecraft configured with low structural mass as the prime objective is presented. Among the major design elements affecting vehicle mass are: maneuverability and re-entry heating, the compatibility of an irregular cargo bay geometry to future mission requirements, the fabrication and assembly of large honeycomb structure fuselage sections, and the development of LOX/LH2 engine extendable nozzles and dual-propulsion schemes. It is shown that vehicle geometry and materials and structural technologies will be the critical areas in the development of such a system.

  4. Capacitive Sensors for Measuring Masses of Cryogenic Fluids

    NASA Technical Reports Server (NTRS)

    Nurge, Mark; Youngquist, Robert

    2003-01-01

    An effort is under way to develop capacitive sensors for measuring the masses of cryogenic fluids in tanks. These sensors are intended to function in both microgravitational and normal gravitational settings, and should not be confused with level sensors, including capacitive ones. A sensor of this type is conceptually simple in the sense that (1) it includes only one capacitor and (2) if properly designed, its single capacitance reading should be readily convertible to a close approximation of the mass of the cryogenic fluid in the tank. Consider a pair of electrically insulated electrodes used as a simple capacitive sensor. In general, the capacitance is proportional to the permittivity of the dielectric medium (in this case, a cryogenic fluid) between the electrodes. The success of design and operation of a sensor of the present type depends on the accuracy of the assumption that to a close approximation, the permittivity of the cryogenic fluid varies linearly with the density of the fluid. Data on liquid nitrogen, liquid oxygen, and liquid hydrogen, reported by the National Institute of Standards and Technology, indicate that the permittivities and densities of these fluids are, indeed, linearly related to within a few tenths of a percent over the pressure and temperature regions of interest. Hence, ignoring geometric effects for the moment, the capacitance between two electrodes immersed in the fluid should vary linearly with the density, and, hence, with the mass of the fluid. Of course, it is necessary to take account of the tank geometry. Because most cryogenic tanks do not have uniform cross sections, the readings of level sensors, including capacitive ones, are not linearly correlated with the masses of fluids in the tanks. In a sensor of the present type, the capacitor electrodes are shaped so that at a given height, the capacitance per unit height is approximately proportional to the cross-sectional area of the tank in the horizontal plane at that

  5. PTV measurements of Lagrangian particle transport by surface gravity wave groups

    NASA Astrophysics Data System (ADS)

    van den Bremer, Ton; Whittaker, Colin; Raby, Alison; Taylor, Paul

    2015-11-01

    We present detailed PTV (particle tracking velocimetry) measurements of the Lagrangian transport and trajectories of neutrally buoyant particles underneath two-dimensional surface gravity wave groups in a laboratory flume. By focussing our attention on wave groups of moderate steepness, we confirm the predictions of standard second-order multi-chromatic wave theory, in which the body of fluid satisfies the potential flow equations. Particles near the surface are transported forwards and their motion is dominated by Stokes drift. Particles at sufficient depth are transported backwards by the Eulerian return current that was first described by Longuet-Higgins & Stewart (1962) and forms an inseparable counterpart of Stokes drift for surface wave groups ensuring the (irrotational) mass balance holds. Finally, we provide experimental validation of a simple scaling relationship, derived based under the assumption of separation of scales, for the transition depth: the depth above which Lagrangian particles are transported forwards by the Stokes drift and below which such particles are transported backwards by the return current. We present results for a range of effective water depths.

  6. Transportation control measure: State Implementation Plan guidance (revised final report)

    SciTech Connect

    Eisinger, D.S.; Deakin, E.A.; Mahoney, L.A.; Morris, R.E.; Ireson, R.G.

    1990-09-01

    The document has been developed for the United States Environmental Protection Agency to summarize current knowledge about transportation control measures (TCMs). The target audience includes transportation and air quality management staff at all government levels. The guidance development effort is motivated by the need to provide post-1987 guidance to attain National Ambient Air Quality Standards (NAAQS). The document provides descriptions and examples of the most frequently implemented TCMs; institutional guidance such as assessing feasibility, agency responsibilities, and funding; and techniques for monitoring and enforcing TCMs. In addition, the document describes the tools available for evaluating TCM impacts on hydrocarbons, nitrogen oxides, and carbon monoxide emissions. Appendices present approaches to estimate TCM effects on PM-10 emissions; important sources of additional information; implementation experiences in various cities; and rules of thumb to quantitatively evaluate TCM transportation system effects. The information presented demonstrates that there have been significant advances in TCM development over the past decade, and that TCMs are appropriate control options for state implementation plans.

  7. Mass spectrometry-based method to investigate the natural selectivity of sucrose as the sugar transport form for plants.

    PubMed

    Yuan, Hang; Wu, Yile; Liu, Wu; Liu, Yan; Gao, Xiang; Lin, Jinming; Zhao, Yufen

    2015-04-30

    Sucrose is the carbon skeletons and energy vector for plants, which is important for plants growth. Among thousands of disaccharides in Nature, why chose sucrose for plants? In this paper, we analyzed the intrinsic structural characteristics of four sucrose isomers with different glycosidic linkage by mass spectrometry (MS) technique. Our results show that sucrose has the most labile glycosidic bond compared with other three isomers, which is helpful for releasing glucose and fructose unit. Besides, sucrose has the most stable integral structure, which is hard to dehydrate and degrade into fragments through losing one or three even four-carbon units, just as its three isomers. In other words, sucrose is more easily holds an integral structure during the transport process, whenever it is necessary, and sucrose can be cleaved into glucose and fructose easily. Besides, we also investigate the internal relationship of sucrose with K(+) by tandem mass spectrometry and viscosity measurement. The related results have shown that the K(+) can stabilize sucrose to a greater extent than the Na(+). Furthermore, under the same conditions, K(+) ions reduce the viscosity of sucrose-water system much more than Na(+). These results suggest that K(+) is a better co-transporter for sucrose. Of course, the transport of sucrose in plants is a very complicated process, which is involved in many proteins. This paper directly accounts for the basic structure feature of sucrose, and the results discovered could provide the novel insight for the answer why Nature chose sucrose for plants.

  8. Effect of ion mass and charge state on transport of vacuum ARC plasmas through a biased magnetic filter

    SciTech Connect

    Byon, Eungsun; Kim, Jong-Kuk; Kwon, Sik-Chol; Anders, Andre

    2003-12-01

    The effect of ion mass and charge state on plasma transport through a 90{sup o}-curved magnetic filter is experimentally investigated using a pulsed cathodic arc source. Graphite, copper, and tungsten were selected as test materials. The filter was a bent copper coil biased via the voltage drop across a low-ohm, ''self-bias'' resistor. Ion transport is accomplished via a guiding electric field, whose potential forms a ''trough'' shaped by the magnetic guiding field of the filter coil. Evaluation was done by measuring the filtered ion current and determination of the particle system coefficient, which can be defined as the ratio of filter ion current, divided by the mean ion charge state, to the arc current. It was found that the ion current and particle system coefficient decreased as the mass-to-charge ratio of ions increased. This result can be qualitatively interpreted by a very simply model of ion transport that is based on compensation of the centrifugal force by the electric force associated with the guiding potential trough.

  9. Measurement of the lifetime difference between Bs mass eigenstates.

    PubMed

    Acosta, D; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Arguin, J-F; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barker, G J; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Ben-Haim, E; Benjamin, D; Beretvas, A; Bhatti, A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Bocci, A; Bodek, A; Bolla, G; Bolshov, A; Booth, P S L; Bortoletto, D; Boudreau, J; Bourov, S; Brau, B; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canepa, A; Casarsa, M; Carlsmith, D; Carron, S; Carosi, R; Cavalli-Sforza, M; Castro, A; Catastini, P; Cauz, D; Cerri, A; Cerrito, L; Chapman, J; Chen, C; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Chu, M L; Chuang, S; Chung, J Y; Chung, W-H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A G; Clark, D; Coca, M; Connolly, A; Convery, M; Conway, J; Cooper, B; Cordelli, M; Cortiana, G; Cranshaw, J; Cuevas, J; Culbertson, R; Currat, C; Cyr, D; Dagenhart, D; Da Ronco, S; D'Auria, S; de Barbaro, P; De Cecco, S; De Lentdecker, G; Dell'Agnello, S; Dell'Orso, M; Demers, S; Demortier, L; Deninno, M; De Pedis, D; Derwent, P F; Dionisi, C; Dittmann, J R; Dörr, C; Doksus, P; Dominguez, A; Donati, S; Donega, M; Donini, J; D'Onofrio, M; Dorigo, T; Drollinger, V; Ebina, K; Eddy, N; Ehlers, J; Ely, R; Erbacher, R; Erdmann, M; Errede, D; Errede, S; Eusebi, R; Fang, H-C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferretti, C; Field, R D; Flanagan, G; Flaugher, B; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J C; Fujii, Y; Furic, I; Gajjar, A; Gallas, A; Galyardt, J; Gallinaro, M; Garcia-Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D W; Gerchtein, E; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giolo, K; Giordani, M; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, D; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Gresele, A; Griffiths, M; Grosso-Pilcher, C; Grundler, U; Guenther, M; da Costa, J Guimaraes; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Handler, R; Happacher, F; Hara, K; Hare, M; Harr, R F; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Hays, C; Hayward, H; Heider, E; Heinemann, B; Heinrich, J; Hennecke, M; Herndon, M; Hill, C; Hirschbuehl, D; Hocker, A; Hoffman, K D; Holloway, A; Hou, S; Houlden, M A; Huffman, B T; Huang, Y; Hughes, R E; Huston, J; Ikado, K; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Issever, C; Ivanov, A; Iwata, Y; Iyutin, B; James, E; Jang, D; Jarrell, J; Jeans, D; Jensen, H; Jeon, E J; Jones, M; Joo, K K; Jun, S Y; Junk, T; Kamon, T; Kang, J; Unel, M Karagoz; Karchin, P E; Kartal, S; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, M S; Kim, S B; Kim, S H; Kim, T H; Kim, Y K; King, B T; Kirby, M; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kobayashi, H; Koehn, P; Kong, D J; Kondo, K; Konigsberg, J; Kordas, K; Korn, A; Korytov, A; Kotelnikov, K; Kotwal, A V; Kovalev, A; Kraus, J; Kravchenko, I; Kreymer, A; Kroll, J; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, J; Lancaster, M; Lander, R; Lannon, K; Lath, A; Latino, G; Lauhakangas, R; Lazzizzera, I; Le, Y; Lecci, C; LeCompte, T; Lee, J; Lee, J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Li, K; Lin, C; Lin, C S; Lindgren, M; Liss, T M; Lister, A; Litvintsev, D O; Liu, T; Liu, Y; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; MacQueen, D; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Manca, G; Marginean, R; Marino, C; Martin, A; Martin, M; Martin, V; Martínez, M; Maruyama, T; Matsunaga, H; Mattson, M; Mazzanti, P; McFarland, K S; McGivern, D; McIntyre, P M; McNamara, P; NcNulty, R; Mehta, A; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miller, L; Miller, R; Miller, J S; Miquel, R; Miscetti, S; Mitselmakher, G; Miyamoto, A; Miyazaki, Y; Moggi, N; Mohr, B; Moore, R; Morello, M; Fernandez, P A Movilla; Mukherjee, A; Mulhearn, M; Muller, T; Mumford, R; Munar, A; Murat, P; Nachtman, J; Nahn, S; Nakamura, I; Nakano, I; Napier, A; Napora, R; Naumov, D; Necula, V; Niell, F; Nielsen, J; Nelson, C; Nelson, T; Neu, C; Neubauer, M S; Newman-Holmes, C; Nigmanov, T; Nodulman, L; Norniella, O; Oesterberg, K; Ogawa, T; Oh, S H; Oh, Y D; Ohsugi, T; Okusawa, T; Oldeman, R; Orava, R; Orejudos, W; Pagliarone, C; Palencia, E; Paoletti, R; Papadimitriou, V; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Pauly, T; Paus, C; Pellett, D; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pitts, K T; Plager, C; Pompos, A; Pondrom, L; Pope, G; Portell, X; Poukhov, O; Prakoshyn, F; Pratt, T; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Rademacker, J; Rahaman, M A; Rakitine, A; Rappoccio, S; Ratnikov, F; Ray, H; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Rimondi, F; Rinnert, K; Ristori, L; Robertson, W J; Robson, A; Rodrigo, T; Rolli, S; Rosenson, L; Roser, R; Rossin, R; Rott, C; Russ, J; Rusu, V; Ruiz, A; Ryan, D; Saarikko, H; Sabik, S; Safonov, A; St Denis, R; Sakumoto, W K; Salamanna, G; Saltzberg, D; Sanchez, C; Sansoni, A; Santi, L; Sarkar, S; Sato, K; Savard, P; Savoy-Navarro, A; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semeria, F; Sexton-Kennedy, L; Sfiligoi, I; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Siegrist, J; Siket, M; Sill, A; Sinervo, P; Sisakyan, A; Skiba, A; Slaughter, A J; Sliwa, K; Smirnov, D; Smith, J R; Snider, F D; Snihur, R; Soha, A; Somalwar, S V; Spalding, J; Spezziga, M; Spiegel, L; Spinella, F; Spiropulu, M; Squillacioti, P; Stadie, H; Stelzer, B; Stelzer-Chilton, O; Strologas, J; Stuart, D; Sukhanov, A; Sumorok, K; Sun, H; Suzuki, T; Taffard, A; Tafirout, R; Takach, S F; Takano, H; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tanimoto, N; Tapprogge, S; Tecchio, M; Teng, P K; Terashi, K; Tesarek, R J; Tether, S; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tollefson, K; Tomura, T; Tonelli, D; Tönnesmann, M; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tseng, J; Tsuchiya, R; Tsuno, S; Tsybychev, D; Turini, N; Turner, M; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vacavant, L; Vaiciulis, A; Varganov, A; Vataga, E; Vejcik, S; Velev, G; Veszpremi, V; Veramendi, G; Vickey, T; Vidal, R; Vila, I; Vilar, R; Vollrath, I; Volobouev, I; von der Mey, M; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wallny, R; Walter, T; Yamashita, T; Yamamoto, K; Wan, Z; Wang, M J; Wang, S M; Warburton, A; Ward, B; Waschke, S; Waters, D; Watts, T; Weber, M; Wester, W C; Whitehouse, B; Wicklund, A B; Wicklund, E; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wolter, M; Worcester, M; Worm, S; Wright, T; Wu, X; Würthwein, F; Wyatt, A; Yagil, A; Yang, C; Yang, U K; Yao, W; Yeh, G P; Yi, K; Yoh, J; Yoon, P; Yorita, K; Yoshida, T; Yu, I; Yu, S; Yu, Z; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zetti, F; Zhou, J; Zsenei, A; Zucchelli, S

    2005-03-18

    We present measurements of the lifetimes and polarization amplitudes for B(0)(s)-->J/psiphi and B(0)(d)-->J/psiK(*0) decays. Lifetimes of the heavy and light mass eigenstates in the B(0)(s) system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203+/-15 B(0)(s) decays we obtain tau(L) = (1.05(+0.16)(-0.13) +/- 0.02) ps and tau(H) = (2.07(+0.58)(-0.46) +/- 0.03) ps. Expressed in terms of the difference DeltaGamma(s) and average Gamma(s), of the decay rates of the two eigenstates, the results are DeltaGamma(s)/Gamma(s) = (65(+25)(-33) +/- 1)% and DeltaGamma(s) = (0.47(+0.19)(-0.24) +/- 0.01) ps(-1).

  10. A Twophase Multirate-Mass Transfer Model for Flow and Transport in Porous Media

    NASA Astrophysics Data System (ADS)

    Dentz, M.; Tecklenburg, J.; Neuweiler, I.; Carrera, J.

    2015-12-01

    We present an upscaled non-local model for two-phase flow and transport in highly heterogeneous porous media. The media under consideration are characterized by sharp contrasts in the hydraulic properties typical for fractured porous media, for example. A two-scale expansion gives an upscaled flow and transport formulation that models multiratemass transfer between mobile (fracture) and immobile (matrix) medium portions. The evolution of saturation due to viscous dominated flow in the mobile domain and mass exchange with the immobile zones through capillary countercurrent flow. The medium heterogeneity is mapped onto the mass transfer parameters, which are encoded in a memory functionthat describes the non-local flux between mobile and immobile zones. The upscaled model is parameterized by the medium heterogeneity and the distribution of hydraulic parameters. Breakthrough of the displaced fluidshows characteristic heavy tails due to fluid retention in immobile zones.

  11. Heat and mass transport resistances in vacuum membrane distillation per drop

    SciTech Connect

    Bandini, S.; Sarti, G.C.

    1999-07-01

    Vacuum membrane distillation (VMD) is a separation process based on the use of microporous hydrophobic membranes. The membrane is located between an aqueous phase and a permeate, which is kept under vacuum at pressure values below the equilibrium vapor pressure of the feed. The liquid stream vaporizes at one side of the membrane, and the vapors diffuse through the gas phase inside the membrane pores. The process rate and performance are affected highly by the transport phenomena both in the liquid phase and through the membrane. Heat- and mass-transfer resistance in the liquid phase, as well as mass-transfer resistance through the membrane, play an important role in determining the process performance. Based on VMD experimental data for several binary aqueous mixtures containing volatile organic compounds, a simple criterion to investigate the role of each transport resistance on the separation efficiency is discussed.

  12. A finite element method for transient analysis of concurrent large deformation and mass transport in gels

    NASA Astrophysics Data System (ADS)

    Zhang, Jiaping; Zhao, Xuanhe; Suo, Zhigang; Jiang, Hanqing

    2009-05-01

    A gel is an aggregate of polymers and solvent molecules. The polymers crosslink into a three-dimensional network by strong chemical bonds and enable the gel to retain its shape after a large deformation. The solvent molecules, however, interact among themselves and with the network by weak physical bonds and enable the gel to be a conduit of mass transport. The time-dependent concurrent process of large deformation and mass transport is studied by developing a finite element method. We combine the kinematics of large deformation, the conservation of the solvent molecules, the conditions of local equilibrium, and the kinetics of migration to evolve simultaneously two fields: the displacement of the network and the chemical potential of the solvent. The finite element method is demonstrated by analyzing several phenomena, such as swelling, draining and buckling. This work builds a platform to study diverse phenomena in gels with spatial and temporal complexity.

  13. Numerical Computation of Mass Transport in Low Reynolds Number Flows and the Concentration Boundary Layer

    NASA Astrophysics Data System (ADS)

    Licata, Nicholas A.; Fuller, Nathaniel J.

    Understanding the physical mechanisms by which an individual cell interacts with its environment often requires detailed information about the fluid in which the cell is immersed. Mass transport between the interior of the cell and the external environment is influenced by the flow of the extracellular fluid and the molecular diffusivity. Analytical calculations of the flow field are challenging in simple geometries, and not generally available in more realistic cases with irregular domain boundaries. Motivated by these problems, we discuss the numerical solution of Stokes equation by implementing a Gauss-Seidel algorithm on a staggered computational grid. The computed velocity profile is used as input to numerically solve the advection-diffusion equation for mass transport. Special attention is paid to the case of two-dimensional flows at large Péclet number. The numerical results are compared with a perturbative analytical treatment of the concentration boundary layer.

  14. Performance of intact and partially degraded concrete barriers in limiting mass transport

    SciTech Connect

    Walton, J.C. )

    1992-06-01

    Mass transport through concrete barriers and release rate from concrete vaults are quantitatively evaluated. The thorny issue of appropriate diffusion coefficients for use in performance assessment calculations is covered, with no ultimate solution found. Release from monolithic concrete vaults composed of concrete waste forms is estimated with a semi-analytical solution. A parametric study illustrates the importance of different parameters on release. A second situation of importance is the role of a concrete shell or vault placed around typical waste forms in limiting mass transport. In both situations, the primary factor controlling concrete performance is cracks. The implications of leaching behavior on likely groundwater concentrations is examined. Frequently, lower groundwater concentrations can be expected in the absence of engineered covers that reduce infiltration.

  15. Upscaling momentum and mass transport under Knudsen and binary diffusion gas slip conditions

    NASA Astrophysics Data System (ADS)

    Valdes-Parada, F. J.; Lasseux, D.

    2015-12-01

    Modeling of gas phase flow in porous media is relevant as it is present in a wide variety of applications ranging from nanofluidic systems to subsurface contaminant transport. In this work, we derive a macroscopic model to study slightly compressible gas flow in porous media for conditions in which the tangential fluid velocity undergoes a slip at the solid interface due to Knudsen effects and to mass diffusion in binary conditions. To this end, we use the method of volume averaging to derive the governing equations at the Darcy scale for both mass and momentum transport. The momentum transport model consists on a modification to Darcy's law due to mass dispersion and to total density gradients. For mass transport, the resulting model is the conventional convection-dispersion equation with two correction terms, one affecting convective transport and the second one affecting mass dispersion due to gas compressibility. The macroscopic model reduces to the one reported by Altevogt et al. (2003) for the case in which gas slip is only due to a concentration gradient and to the one by Lasseux et al. (2014) under Knudsen slip conditions. The model is written in terms of effective-medium coefficients that can be predicted from solving the associated closure problems in representative unit cells. For conditions in which the Péclet number is much greater than one and when the Knudsen number is not exceedingly small compared to the unity, our computations show that the predictions of the longitudinal dispersion may reach an error as high as 60% compared to the predictions obtained by ignoring gas slip. Altevogt A.S., Rolston D.E., Whitaker S. New equations for binary gas transport in porous media, Part 1: equation development. Advances in Water Resources, Vol. 26, 695-715, 2003. Lasseux D., Valdés-Parada F.J., Ochoa-Tapia J.A., Goyeau B. A macroscopic model for slightly compressible gas slip-flow in homogeneous porous media. Physics of Fluids, Vol. 26, 053102, 2014.

  16. Sub-barrier reactions measured using a recoil mass separator

    SciTech Connect

    Betts, R.R.

    1988-01-01

    Few data exist in the sub-barrier region for reaction channels other than fusion. In particular, our experimental knowledge of quasi-elastic transfer reactions is sparse, despite the belief that this particular channel may be dominant in determining some features of the sub-barrier fusion enhancement. Transfer reactions are governed primarily by the closet approach of the colliding nuclei which, at low energies, results in a strong backward peaking of the angular distribution in the center-of-mass frame. For situations where the projectile has a significant fraction of the target mass, as is so in most cases of interest, the backscattered projectile-like fragment has such low energy that the usual techniques of measurement and identification become invalid. Here, we report on a solution to this problem which allows a systematic study of many aspects of transfer reactions in the energy regime of interest. We exploit the fact that associated with the low-energy backscattered projectile-like fragment is a complementary target-like fragment which recoils to forward angles with a large fraction of the incident beam energy. These target-like fragments were detected and identified using the Daresbury Recoil Mass Separator thus allowing the measurement of quasi-elastic transfer over hitherto inaccessible energy range from the vicinity of the barrier to several tens of MeV below. The experiments described here used VYNi beams of energies ranging from 180 to 260 MeV provided by the Daresbury Laboratory Nuclear Structure Facility tandem accelerator. Data on sub-barrier transfer for targets of /sup 116,118,120,122,124/Sn and /sup 144,148,150,152,154/Sm were obtained. 16 refs., 10 figs., 2 tabs.

  17. Quantum limits to center-of-mass measurements

    SciTech Connect

    Vaughan, Timothy; Drummond, Peter; Leuchs, Gerd

    2007-03-15

    We discuss the issue of measuring the mean position (center of mass) of a group of bosonic or fermionic quantum particles, including particle number fluctuations. We introduce a standard quantum limit for these measurements at ultralow temperatures, and discuss this limit in the context of both photons and ultracold atoms. In the case of non-interacting harmonically trapped fermions, we present evidence that the Pauli exclusion principle has a strongly beneficial effect, giving rise to a 1/N scaling in the position standard deviation--as opposed to a 1/{radical}(N) scaling for bosons. The difference between the actual mean-position fluctuation and this limit is evidence for quantum wave-packet spreading in the center of mass. This macroscopic quantum effect cannot be readily observed for noninteracting particles, due to classical pulse broadening. For this reason, we also study the evolution of photonic and matter-wave solitons, where classical dispersion is suppressed. In the photonic case, we show that the intrinsic quantum diffusion of the mean position can contribute significantly to uncertainties in soliton pulse arrival times. We also discuss ways in which the relatively long lifetimes of attractive bosons in matter-wave solitons may be used to demonstrate quantum interference between massive objects composed of thousands of particles.

  18. Measurement of Surface Composition for the Icy Galilean Moons Via Neutral and Ion Mass Spectrometry from Orbit with JIMO

    NASA Technical Reports Server (NTRS)

    Wong, M.; Berthelier, J.; Carlson, R.; Cooper, J.; Johnson, R.; Jurac, S.; Leblanc, F.; Shematovich, V.

    2003-01-01

    In this paper, we will provide insights into mass spectrometer requirements. In addition, we will describe the modeling of the neutrals ejected from likely surface materials and their ionization rates in the Jovian environment. We will use such models to connect the mass spectra measurements of the freshly formed ions to surface composition. We will also discuss what possible compositional signatures are for endogenic materials other than water ice. Finally, since a goal is to identify material composition with surface features, we will describe the transport of neutrals ejected from the surface prior to detection by either an ion or neutral mass spectrometer.

  19. Field measurements of tracer gas transport by barometric pumping

    SciTech Connect

    Lagus, P.L.; McKinnis, W.B.; Hearst, J.R.; Burkhard, N.R.; Smith, C.F.

    1994-07-28

    Vertical gas motions induced by barometric pressure variations can carry radioactive gases out of the rubblized region produced by an underground nuclear explosion, through overburden rock, into the atmosphere. To better quantify transit time and amount of transport, field experiments were conducted at two sites on Pahute Mesa, Kapelli and Tierra, where radioactive gases had been earlier detected in surface cracks. At each site, two tracer gases were injected into the rubblized chimney 300-400 m beneath the surface and their arrival was monitored by concentration measurements in gas samples extracted from shallow collection holes. The first ``active`` tracer was driven by a large quantity of injected air; the second ``passive`` tracer was introduced with minimal gas drive to observe the natural transport by barometric pumping. Kapelli was injected in the fall of 1990, followed by Tierra in the fall of 1991. Data was collected at both sites through the summer of 1993. At both sites, no surface arrival of tracer was observed during the active phase of the experiment despite the injection of several million cubic feet of air, suggesting that cavity pressurization is likely to induce horizontal transport along high permeability layers rather than vertical transport to the surface. In contrast, the vertical pressure gradients associated with barometric pumping brought both tracers to the surface in comparable concentrations within three months at Kapelli, whereas 15 months elapsed before surface arrival at Tierra. At Kapelli, a quasisteady pumping regime was established, with tracer concentrations in effluent gases 1000 times smaller than concentrations thought to exist in the chimney. Tracer concentrations observed at Tierra were typically an order of magnitude smaller. Comparisons with theoretical calculations suggest that the gases are traveling through {approximately}1 millimeter vertical fractures spaced 2 to 4 meters apart. 6 refs., 18 figs., 3 tabs.

  20. New mass measurement of {sup 6}Li and ppb-level systematic studies of the Penning trap mass spectrometer TITAN

    SciTech Connect

    Brodeur, M.; Ettenauer, S.; Smith, M.; Dilling, J.; Brunner, T.; Champagne, C.; Lapierre, A.; Ringle, R.; Ryjkov, V. L.; Delheij, P.; Audi, G.; Lunney, D.

    2009-10-15

    The frequency ratio of {sup 6}Li to {sup 7}Li was measured using the TITAN Penning trap mass spectrometer. This measurement resolves a 16-ppb discrepancy between the {sup 6}Li mass of 6.015 122 795(16) u from the Atomic Mass Evaluation 2003 (AME03), which is based on a measurement by JILATRAP, and the more recent measurement of 6.015 122 890(40) u by SMILETRAP. Our measurement agrees with SMILETRAP and a more precise mass value for {sup 6}Li of 6.015 122 889(26) u is presented along with systematic evaluations of the measurement uncertainties. This result makes {sup 6}Li a solid anchor point for future mass measurements on highly charged ions with m/q{approx}6.

  1. On dynamical formulations of a tethered satellite system with mass transport

    NASA Astrophysics Data System (ADS)

    Liu, F. C.

    1985-01-01

    Two satellites connected by a long flexible tether along the earth radial direction comprise a stable equilibrium state. This paper deals with formulations of in-plane motion of the tether connected satellites with a third mass transporting from one satellite to the other. Systems of equations of motion formulated by two methods, Lagrange equations and D'Alembert's Principle, are presented and methods for numerical solutions are proposed. Initial conditions for inward and outward transfers are derived.

  2. Mass transport phenomena during solidification in microgravity; preliminary results of the first Mephisto flight experiment

    NASA Astrophysics Data System (ADS)

    Favier, J. J.; Garandet, J. P.; Rouzaud, A.; Camel, D.

    1994-06-01

    The MEPHISTO space facility flew on the Columbia space shuttle in October 1992. The preliminary scientific results, mainly based on the analysis of the Seebeck signal, are presented in this paper. Valuable information was obtained for both planar and cellular solidification regimes. It is shown that mass transfer in the melt during the flight was principally diffusive; however, even in microgravity, slow growth rates may result in significant convective transport. A tentative interpretation of the Seebeck signal for destabilized interfaces is also proposed.

  3. Final Report - Ion Production and Transport in Atmospheric Pressure Ion Source Mass Spectrometers

    SciTech Connect

    Farnsworth, Paul B.; Spencer, Ross L.

    2014-05-14

    This document is the final report on a project that focused in the general theme of atmospheric-pressure ion production and transport for mass spectrometry. Within that general theme there were two main projects: the fundamental study of the transport of elemental ions through the vacuum interface of an inductively coupled plasma mass spectrometer (ICPMS), and fundamental studies of the ionization mechanisms in ambient desorption/ionization (ADI) sources for molecular mass spectrometry. In both cases the goal was to generate fundamental understanding of key instrumental processes that would lead to the development of instruments that were more sensitive and more consistent in their performance. The emphasis on consistency derives from the need for instruments that have the same sensitivity, regardless of sample type. In the jargon of analytical chemistry, such instruments are said to be free from matrix effects. In the ICPMS work each stage of ion production and of ion transport from the atmospheric pressure to the high-vacuum mass analyzer was studied. Factors controlling ion transport efficiency and consistency were identified at each stage of pressure reduction. In the ADI work the interactions between an electrospray plume and a fluorescent sample on a surface were examined microscopically. A new mechanism for analyte ion production in desorption electrospray ionization (DESI) was proposed. Optical spectroscopy was used to track the production of reactive species in plasmas used as ADI sources. Experiments with mixed-gas plasmas demonstrated that the addition of a small amount of hydrogen to a helium ADI plasma could boost the sensitivity for some analytes by over an order of magnitude.

  4. In situ global method for measurement of oxygen demand and mass transfer

    SciTech Connect

    Klasson, K.T.; Lundbaeck, K.M.O.; Clausen, E.C.; Gaddy, J.L.

    1997-05-01

    Two aerobic microorganisms, Saccharomycopsis lipolytica and Brevibacterium lactofermentum, have been used in a study of mass transfer and oxygen uptake from a global perspective using a closed gas system. Oxygen concentrations in the gas and liquid were followed using oxygen electrodes, and the results allowed for easy calculation of in situ oxygen transport. The cell yields on oxygen for S. lipolytica and B. lactofermentum were 1.01 and 1.53 g/g respectively. The mass transfer coefficient was estimated as 10 h{sup {minus}1} at 500 rpm for both fermentations. The advantages with this method are noticeable since the use of model systems may be avoided, and the in situ measurements of oxygen demand assure reliable data for scale-up.

  5. Application of Paramagnetically Tagged Molecules for Magnetic Resonance Imaging of Biofilm Mass Transport Processes▿

    PubMed Central

    Ramanan, B.; Holmes, W. M.; Sloan, W. T.; Phoenix, V. R.

    2010-01-01

    Molecules become readily visible by magnetic resonance imaging (MRI) when labeled with a paramagnetic tag. Consequently, MRI can be used to image their transport through porous media. In this study, we demonstrated that this method could be applied to image mass transport processes in biofilms. The transport of a complex of gadolinium and diethylenetriamine pentaacetic acid (Gd-DTPA), a commercially available paramagnetic molecule, was imaged both in agar (as a homogeneous test system) and in a phototrophic biofilm. The images collected were T1 weighted, where T1 is an MRI property of the biofilm and is dependent on Gd-DTPA concentration. A calibration protocol was applied to convert T1 parameter maps into concentration maps, thus revealing the spatially resolved concentrations of this tracer at different time intervals. Comparing the data obtained from the agar experiment with data from a one-dimensional diffusion model revealed that transport of Gd-DTPA in agar was purely via diffusion, with a diffusion coefficient of 7.2 × 10−10 m2 s−1. In contrast, comparison of data from the phototrophic biofilm experiment with data from a two-dimensional diffusion model revealed that transport of Gd-DTPA inside the biofilm was by both diffusion and advection, equivalent to a diffusion coefficient of 1.04 × 10−9 m2 s−1. This technology can be used to further explore mass transport processes in biofilms, either by using the wide range of commercially available paramagnetically tagged molecules and nanoparticles or by using bespoke tagged molecules. PMID:20435773

  6. Skin Friction and Transition Location Measurement on Supersonic Transport Models

    NASA Technical Reports Server (NTRS)

    Kennelly, Robert A., Jr.; Goodsell, Aga M.; Olsen, Lawrence E. (Technical Monitor)

    2000-01-01

    Flow visualization techniques were used to obtain both qualitative and quantitative skin friction and transition location data in wind tunnel tests performed on two supersonic transport models at Mach 2.40. Oil-film interferometry was useful for verifying boundary layer transition, but careful monitoring of model surface temperatures and systematic examination of the effects of tunnel start-up and shutdown transients will be required to achieve high levels of accuracy for skin friction measurements. A more common technique, use of a subliming solid to reveal transition location, was employed to correct drag measurements to a standard condition of all-turbulent flow on the wing. These corrected data were then analyzed to determine the additional correction required to account for the effect of the boundary layer trip devices.

  7. Direct measurements of transport properties are essential for site characterization

    SciTech Connect

    Wright, J.; Conca, J.L.

    1994-08-01

    Direct measurements of transport parameters on subsurface sediments using, the UFA method provided detailed hydrostratigraphic mapping, and subsurface flux distributions at a mixed-waste disposal site at Hanford. Seven hundred unsaturated conductivity measurements on fifty samples were obtained in only six months total of UFA run time. These data are used to provide realistic information to conceptual models, predictive models and restoration strategies. The UFA instrument consists of an ultracentrifuge with a constant, ultralow flow pump that provides fluid to the sample surface through a rotating seal assembly and microdispersal system. Effluent from the sample is collected in a transparent, volumetrically-calibrated chamber at the bottom of the sample assembly. Using a strobe light, an observer can check the chamber while the sample is being centrifuged. Materials can be run in the UFA as recomposited samples or in situ samples can be subcored directly into the sample UFA chamber.

  8. A collision-based model for measuring bedload transport from the seismic waves generated by rivers

    NASA Astrophysics Data System (ADS)

    Roth, D. L.; Finnegan, N. J.; Brodsky, E. E.; Stark, C. P.

    2011-12-01

    Accurately predicting rates of coarse sediment transport in river channels is a central goal of fluvial geomorphology and civil engineering. However, it is difficult to evaluate sediment transport and bedrock abrasion models in large rivers because quantitative measures of bedload transport are labor intensive and often dangerous to obtain in floods. Two recent studies show that the amplitude of seismic waves near rivers may record bedload flux, indicating that seismometers near rivers provide a potential means of monitoring bedload transport. In an effort to better interpret seismic waves generated by rivers, we seek a relationship between the variables governing bedload transport and seismic waves. Our approach relies on the fact that elastic waves are generated when momentum is transferred to the bed during a bedload particle impact. For an impacting particle of known mass and velocity, the momentum transfer can be computed from Hertzian impact theory. Here we combine analytic results based on Hertzian and elastic wave theories with empirical equations developed to describe the ballistics of bedload particles in terms of fluid shear stress and grain size. From this synthesis we arrive at a semi-analytic expression that predicts how the characteristic frequencies and amplitudes of seismic waves generated from saltating bedload particles should scale with fluid shear stress, grain size, and coarse sediment flux. Preliminary tests of our predictions using previously published and newly acquired laboratory data indicate that seismic signals near rivers can record information about the size, velocity and number of particles impacting the bed. Additionally, our analytical results help identify bedload transport events in seismic data collected along the Chijiawan River in Taiwan. Here the river is evolving rapidly in response to a dam removal - resulting in predictable changes in bedload transport efficiency in time and space that we can compare to local seismic data.

  9. Spin transport measurements in gallium arsenide quantum dots

    NASA Astrophysics Data System (ADS)

    Folk, Joshua Alexander

    This thesis presents a series of measurements investigating the spin physics of lateral quantum dots, defined electrostatically in the 2-D electron gas at the interface of a GaAs/AlGaAs heterostructure. The experiments span a range from open dots, where the leads of the dot carry at least one fully transmitting mode, to closed dots, where the leads are set to be tunnel barriers. For open dots, spin physics is inferred from measurements of conductance fluctuations; the effects of spin degeneracy in the orbital levels as well as a spin-orbit interaction are observed. In the closed dot measurements, ground state spin transitions as electrons are added to the dot may be determined from the motion of Coulomb blockade peaks in an in-plane magnetic field. In addition, this thesis demonstrates for the first time a direct measurement of the spin polarization of current emitted from a quantum dot, or a quantum point contact, during transport. These experiments make use of a spin-sensitive focusing geometry in which a quantum point contact serves as a spin analyzer for the mesoscopic device under test. Measurements are presented both in the open dot regime, where good agreement with theory is found, as well as the closed dot regime, where the data defies a simple theoretical explanation.

  10. Measurements and modeling of deposited particle transport by foot traffic indoors.

    PubMed

    Sippola, Mark R; Sextro, Richard G; Thatcher, Tracy L

    2014-04-01

    Deposited particles are transported into and within buildings by adhering to and releasing from people's shoes. To better understand transport of deposited particulate contaminants and exposures to these materials, experimental data on tracking by foot traffic are needed. Laboratory experiments measured uptake and downlay mass transfer efficiencies of particles between shoes and floors in a step-simulation chamber. Equilibrium uptake transfer fractions, the net mass fraction transferred from floors to shoes after several steps, were also measured. Single-step uptake and downlay transfer efficiencies ranged from 0.02 to 0.22 and equilibrium uptake transfer fractions were 0.10-0.40. Particle size, particle loading, shoe type, floor type, step pressure, and step sequence were all investigated. Experiments demonstrated that single-step downlay transfer efficiencies decrease with each successive step onto clean floors. A simple empirical model is proposed to estimate these transfers as a function of step number. Simulations using the transfer efficiency values measured here illustrate the spread of deposited particles by people walking in a hypothetical hallway. These simulations show that in locations where a few people walk over the same area each minute, tracking can spread deposited material over length scales comparable to building dimensions in just a few hours.

  11. Quantifying the contribution of long-range transport to Particulate Matter (PM) mass loadings at a suburban site in the North-Western Indo Gangetic Plain (IGP)

    NASA Astrophysics Data System (ADS)

    Pawar, H.; Garg, S.; Kumar, V.; Sachan, H.; Arya, R.; Sarkar, C.; Chandra, B. P.; Sinha, B.

    2015-04-01

    Many sites in the densely populated Indo Gangetic Plain (IGP) frequently exceed the national ambient air quality standard (NAAQS) of 100 μg m-3 for 24 h average PM10 and 60 μg m-3 for 24 h average PM2.5 mass loadings, exposing residents to hazardous levels of PM throughout the year. We quantify the contribution of long range transport to elevated PM levels and the number of exceedance events through a back trajectory climatology analysis of air masses arriving at the IISER Mohali Atmospheric Chemistry facility (30.667° N, 76.729° E; 310 m a.m.s.l.) for the period August 2011-June 2013. Air masses arriving at the receptor site were classified into 6 clusters, which represent synoptic scale air mass transport patterns and the average PM mass loadings and number of exceedance events associated with each air mass type were quantified for each season. Long range transport from the west leads to significant enhancements in the average coarse mode PM mass loadings during all seasons. The contribution of long range transport from the west and south west (Source region: Arabia, Thar desert, Middle East and Afghanistan) to coarse mode PM varied between 9 and 57% of the total PM10-2.5 mass. Local pollution episodes (wind speed < 1 m s-1) contributed to enhanced coarse mode PM only during winter season. South easterly air masses (Source region: Eastern IGP) were associated with significantly lower coarse mode PM mass loadings during all seasons. For fine mode PM too, transport from the west usually leads to increased mass loadings during all seasons. Local pollution episodes contributed to enhanced PM2.5 mass loadings during winter and summer season. South easterly air masses were associated with significantly lower PM2.5 mass loadings during all seasons. Using simultaneously measured gas phase tracers we demonstrate that most PM2.5 originated from combustion sources. The fraction of days in each season during which the PM mass loadings exceeded the national ambient air

  12. Use of alternate healthcare facilities as alternate transport destinations during a mass-casualty incident.

    PubMed

    Glassman, Erik S; Parrillo, Steven J

    2010-01-01

    The purpose of this discussion is to review the use of destinations other than the hospital emergency department, to transport patients injured as a result of a mass-casualty incident (MCI). A MCI has the ability to overwhelm traditional hospital resources normally thought of as appropriate destinations for the transport of injured patients. As a result, those with less severe injuries often are required to wait before they can receive definitive treatment. This waiting period, either at the scene of the incident or in the emergency department, can increase morbidity and drain resources that can be better directed toward the transport and care of those more severely injured. Potential alternate transport destinations include physician office buildings, ambulatory care centers, ambulatory surgery centers, and urgent care centers. By allowing for transport to alternate locations, these less severely injured patients can be removed rapidly from the scene, treated, and potentially released. This effort can decrease the strain on traditional resources within the system, better allowing these resources to treat more seriously injured patients.

  13. Gas composition measurements in arc heated flowfields via mass spectrometry

    NASA Astrophysics Data System (ADS)

    Willey, Ronald J.; Blake, David J.

    1991-06-01

    Gas compositions for an arc heated flowfield were determined by mass spectrometry on gas samples drawn from the flowfield through a sample probe. Surveys were made across the freestream flow using sample probes made of copper and quartz. Oxygen atoms reaching the mass spectrometer ranged from 6 to 9.4 percent and was a direct function of arc heater current and resultant stream enthalpy. Likewise, mole percents of nitrogen atoms ranged from 13.5 to 19 for total enthalpies of 7.0 to 18.4 MJ/kg. Species gradients existed in both the radial and axial directions. Atomic concentrations were highest near the centerline and at the nozzle exit. A species survey was completed around a shock that was established by a copper blunt body placed in the flowfield. The results showed strong species gradients following the shock edge, with atom mole fractions highest along the shock edge. Overall, the results provide insight into gas composition by point measurements in arc heated flowfields. The results suggest that nitrogen may begin dissociating before all of the oxygen dissociates, and that past assumptions based on frozen chemistry models may be faulty.

  14. Octupole Excitation of Trapped Ion Motion for Precision Mass Measurements

    NASA Astrophysics Data System (ADS)

    Bollen, G.; Ringle, R.; Schury, P.; Schwarz, S.; Sun, T.

    2005-04-01

    National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI, USA An azimuthal octupole radiofrequency field has been used to excite the ion motion of ^40Ar^+ ions stored in a Penning trap. A resonant response was observed at twice the ions' true cyclotron frequency φc=q/m.B. The experiment has been performed with the 9.4-T Penning trap system of the recently commissioned LEBIT facility at the NSCL at MSU [1]. Similar to the excitation with an azimuthal quadrupole field at φc [2,3], octupole excitation at 2φc gives rise to a periodic beating of the ion motion between magnetron and reduced cyclotron motion. Differences are observed in the dependence of the excited ion motion on initial amplitudes and phases of the radial eigen motions. The observed behavior of the ions is found to be in good agreement with the results of numerical simulations. The technique still requires further testing but the first results indicate that 2φc excitation may provide benefits that are similar to doubling the magnetic field strength B. In particular precision mass measurements of short-lived rare isotopes may benefit from this technique by being able to reach a given precision with shorter ion storage and observation times. [1] S. Schwarz et al, Nucl. Instr. Meth. B204 (2004) 507 [2] G. Bollen et al., J. Appl. Phys. 68 (1990) 4355 [3] M. König et al., Int. J. Mass Spec. Ion. Proc. 142 (1995) 95

  15. Using a portable mass spectrometer to measure surface contamination

    SciTech Connect

    Gregg, H.; Meltzer, M.; Lindsey, J.; Edberg, H.

    1995-12-31

    One of the major sources of hazardous waste and VOC air emissions throughout manufacturing industry is parts and equipment cleaning operations. Modification of the cleaning process to use non-hazardous cleaning agents may be the best way to these sources, but some operations still require the use of hazardous solvents. Monitoring the contamination levels during cleaning operations can provide useful feedback for reducing waste generation and air emissions due to over- or under-cleaning. Near real-time evaluation of cleaning operations can help reduce pollution in a wide variety of industries, including aerospace, electronics, and metal finishing industries. The authors have developed a mass spectrometry based analyzer that has similar or better sensitivity than ellipsometry or FTIR and is more tolerant of surface conditions and composition. In addition, the instrument is relatively portable and can be used to help identify unknown surface contamination. This method uses vacuum and thermal desorption to remove volatile and semi-volatile contaminants from the surface. A quadrupole mass spectrometer is used to identify and measure the contamination. A bench-scale model of this {open_quotes}contamination analysis unit{close_quotes} employs a residual gas analyzer (RGA) mated to a small, internally heated inlet that samples a surface.

  16. Technetium measurements by accelerator mass spectrometry at LLNL

    NASA Astrophysics Data System (ADS)

    Bergquist, B. A.; Marchetti, A. A.; Martinelli, R. E.; McAninch, J. E.; Nimz, G. J.; Proctor, I. D.; Southon, J. R.; Vogel, J. S.

    2000-10-01

    Technetium-99 is a long-lived, high-abundance fission product which has been widely distributed in the environment through atmospheric testing, the nuclear fuel cycle, and nuclear medicine. It has a high potential for migration in the environment as the pertechnetate anion. At the Center for Accelerator Mass Spectrometry, methods are being developed for the detection of this radionuclide by accelerator mass spectrometry (AMS), including extraction from environmental samples, concentration and purification of the 99Tc, conversion to a form appropriate for AMS analysis, and quantification by AMS. Besides interference from the stable (though relatively rare) atomic isobar 99Ru, the detection of 99Tc by AMS presents some technical challenges which are not present for the other radionuclides typically measured by AMS. These challenges are related to the lack of a stable Tc isotope. Here we present the status of our 99Tc methods including discussion of interferences and sensitivity, and recent results for environmental samples and the IAEA reference material IAEA-381, Irish Sea Water. Sensitivity is presently ˜10 μBq (˜1×10 8 atoms) per sample, limited primarily by 99Ru introduced from process chemicals, and precision/reproducibility is ˜15-25%.

  17. Giant Mass Transport Deposits of the Caribbean Margin and their Tsunamigenic Potential, Offshore Northern Colombia

    NASA Astrophysics Data System (ADS)

    Leslie, S.; Mann, P.; Carvajal, L. C.

    2014-12-01

    Three large (170-290 m thick, >1000 km3) Mass Transport Deposits (MTDs) are recognized on seismic lines offshore northern Colombia covering a combined area of 27,000 km2, an area the size of the state of Massachusetts. These deposits record a number of massive slope failure events along the Northern Colombian Margin proximal to the actively prograding delta and fan of the Magdalena River, the 26th largest river in the world by discharge volume . The largest MTD covers an area >15,000 km2 outboard of the toe of the continental slope on the abyssal sea floor; the two smaller MTDs range from 5000 to 7000 km2 in area. The volume of the largest deposited measured from >160 km of seismic reflection data ranges from 2000 and 5000 km3, comparable in size to the giant Storegga Slide offshore Norway (3500 km3) and the Nuuanu slide offshore the island of Oahu, Hawai'i (~3000 km3). The timing of the MTDs can be constrained from sparse wells and seismic data to be mid to late Miocene (15-5.3 Ma) through the Plio-Pleistocene (2.6 Ma). Likely causative factors for the MTDs include: 1) elevated pore pressure due to generation of biogenic gas in the sediment column of the continental slopes as observed on seismic reflection data; 2) rapid sedimentation related to the Magdalena delta that has produced oversteepened slopes since the late Miocene (7-10 Ma); and 3) tectonic uplift and infrequent large earthquakes related to shallow, southeastward subduction beneath the nearby Southern Caribbean Fold Belt. Preliminary models of inferred tsunamis and their projected run-ups around the Caribbean Sea are presented.

  18. Representative Elementary Length to Measure Soil Mass Attenuation Coefficient

    PubMed Central

    Borges, J. A. R.; Pires, L. F.; Costa, J. C.

    2014-01-01

    With increasing demand for better yield in agricultural areas, soil physical property representative measurements are more and more essential. Nuclear techniques such as computerized tomography (CT) and gamma-ray attenuation (GAT) have been widely employed with this purpose. The soil mass attenuation coefficient (μs) is an important parameter for CT and GAT analysis. When experimentally determined (μes), the use of suitable sized samples enable to evaluate it precisely, as well as to reduce measurement time and costs. This study investigated the representative elementary length (REL) of sandy and clayey soils for μes measurements. Two radioactive sources were employed (241Am and 137Cs), three collimators (2–4 mm diameters), and 14 thickness (x) samples (2–15 cm). Results indicated ideal thickness intervals of 12–15 and 2–4 cm for the sources 137Cs and 241Am, respectively. The application of such results in representative elementary area (REA) evaluations in clayey soil clods via CT indicated that μes average values obtained for x > 4 cm and source 241Am might induce to the use of samples which are not large enough for soil bulk density evaluations (ρs). As a consequence, ρs might be under- or overestimated, generating inaccurate conclusions about the physical quality of the soil under study. PMID:24672338

  19. Wave-induced mass transport affects daily Escherichia coli fluctuations in nearshore water

    USGS Publications Warehouse

    Ge, Zhongfu; Whitman, Richard L.; Nevers, Meredith B.; Phanikumar, Mantha S.

    2012-01-01

    Characterization of diel variability of fecal indicator bacteria concentration in nearshore waters is of particular importance for development of water sampling standards and protection of public health. Significant nighttime increase in Escherichia coli (E. coli) concentration in beach water, previously observed at marine sites, has also been identified in summer 2000 from fixed locations in waist- and knee-deep waters at Chicago 63rd Street Beach, an embayed, tideless, freshwater beach with low currents at night (approximately 0.015 m s–1). A theoretical model using wave-induced mass transport velocity for advection was developed to assess the contribution of surface waves to the observed nighttime E. coli replenishment in the nearshore water. Using average wave conditions for the summer season of year 2000, the model predicted an amount of E. coli transported from water of intermediate depth, where sediment resuspension occurred intermittently, that would be sufficient to have elevated E. coli concentration in the surf and swash zones as observed. The nighttime replenishment of E. coli in the surf and swash zones revealed here is an important phase in the cycle of diel variations of E. coli concentration in nearshore water. According to previous findings in Ge et al. (Environ. Sci. Technol. 2010, 44, 6731–6737), enhanced current circulation in the embayment during the day tends to displace and deposit material offshore, which partially sets up the system by the early evening for a new period of nighttime onshore movement. This wave-induced mass transport effect, although facilitating a significant base supply of material shoreward, can be perturbed or significantly influenced by high currents (orders of magnitude larger than a typical wave-induced mass transport velocity), current-induced turbulence, and tidal forcing.

  20. A micro-mapping strategy to investigate mechanical and chemical mass transport in migmatite

    NASA Astrophysics Data System (ADS)

    Lanari, Pierre; Riel, Nicolas

    2016-04-01

    Migmatites are fantastic objects to study both mechanical and chemical mass transport occurring at mm to cm-scale. However, migmatitic outcrops are the result of complex space and time interactions between (i) melt producing reactions, (ii) melt gain/loss and (iii) retrograde reactions. This succession of events is recorded in the minerals and microstructures of migmatites, and accounts for their apparent complexity. In order to explore the controlling parameters of these chemico-mechanical mass transport, it is thus necessary to characterize in great details the compositional changes between the different migmatitic domains, such as between leucosome and residuum. In this contribution we show how suitable local effective bulk (LEB) compositions can be derived by means of standardized microprobe X-ray images, using the program XMapTools. For chemically heterogeneous samples, such as migmatites, these LEB allow to forward model the stable mineral assemblages for each domain. Those thermodynamic models are used to investigate the conditions of leucosome-residuum separation. The studied sample is a metapelite embedded within a metasedimentary xenolith in the Marcabeli pluton, El Oro Complex, Ecuador. The sample exhibits complex mineral patterns due to local melt redistribution (at mm to cm-scale). Such physical mass transport involves major changes that affect the local chemical composition observed today. At the same time gradients in chemical potential can be established between adjacent domains such as residuum and leucosome, thus triggering chemical interaction. Diffusive transport between domains aims to reduce such chemical potential gradients. Along a modelled P-T path the chemical and mineralogical evolution of micro-domains can be reconstructed for (at least the reactive parts of) the crystallization history.

  1. Low-level 14C measurements and Accelerator Mass Spectrometry

    SciTech Connect

    Litherland, A.E.; Beukens, R.P.; Zhao, X.-L.; Kieser, W.E.; Gove, H.E.

    2005-09-08

    Accelerator Mass Spectrometry (AMS) and isotope enrichment were used in 1991 to estimate that the 14C content of methane in natural gas was {<=}1.6x10-18 of the total carbon. The low content of 14C in underground hydrocarbons was verified later in the remarkable results from the Borexino test scintillation counter for solar neutrino studies. Since then studies of the 14C background problem have demonstrated that much of the background originally observed in the AMS measurements can, in principle, be eliminated. However, many difficulties and other backgrounds are to be faced as the limit for AMS is pushed still further towards possibly a ratio of < 10-21. These will be discussed.

  2. Pinning down the superfluid and measuring masses using pulsar glitches

    PubMed Central

    Ho, Wynn C. G.; Espinoza, Cristóbal M.; Antonopoulou, Danai; Andersson, Nils

    2015-01-01

    Pulsars are known for their superb timing precision, although glitches can interrupt the regular timing behavior when the stars are young. These glitches are thought to be caused by interactions between normal and superfluid matter in the crust of the star. However, glitching pulsars such as Vela have been shown to require a superfluid reservoir that greatly exceeds that available in the crust. We examine a model in which glitches tap the superfluid in the core. We test a variety of theoretical superfluid models against the most recent glitch data and find that only one model can successfully explain up to 45 years of observational data. We develop a new technique for combining radio and x-ray data to measure pulsar masses, thereby demonstrating how current and future telescopes can probe fundamental physics such as superfluidity near nuclear saturation. PMID:26601293

  3. A tandem mass spectrometric method for singlet oxygen measurement.

    PubMed

    Karonen, Maarit; Mattila, Heta; Huang, Ping; Mamedov, Fikret; Styring, Stenbjörn; Tyystjärvi, Esa

    2014-01-01

    Singlet oxygen, a harmful reactive oxygen species, can be quantified with the substance 2,2,6,6-tetramethylpiperidine (TEMP) that reacts with singlet oxygen, forming a stable nitroxyl radical (TEMPO). TEMPO has earlier been quantified with electron paramagnetic resonance (EPR) spectroscopy. In this study, we designed an ultra-high-performance liquid chromatographic-tandem mass spectrometric (UHPLC-ESI-MS/MS) quantification method for TEMPO and showed that the method based on multiple reaction monitoring (MRM) can be used for the measurements of singlet oxygen from both nonbiological and biological samples. Results obtained with both UHPLC-ESI-MS/MS and EPR methods suggest that plant thylakoid membranes produce 3.7 × 10(-7) molecules of singlet oxygen per chlorophyll molecule in a second when illuminated with the photosynthetic photon flux density of 2000 μmol m(-2 ) s(-1). PMID:24849296

  4. Pinning down the superfluid and measuring masses using pulsar glitches.

    PubMed

    Ho, Wynn C G; Espinoza, Cristóbal M; Antonopoulou, Danai; Andersson, Nils

    2015-10-01

    Pulsars are known for their superb timing precision, although glitches can interrupt the regular timing behavior when the stars are young. These glitches are thought to be caused by interactions between normal and superfluid matter in the crust of the star. However, glitching pulsars such as Vela have been shown to require a superfluid reservoir that greatly exceeds that available in the crust. We examine a model in which glitches tap the superfluid in the core. We test a variety of theoretical superfluid models against the most recent glitch data and find that only one model can successfully explain up to 45 years of observational data. We develop a new technique for combining radio and x-ray data to measure pulsar masses, thereby demonstrating how current and future telescopes can probe fundamental physics such as superfluidity near nuclear saturation.

  5. Pinning down the superfluid and measuring masses using pulsar glitches.

    PubMed

    Ho, Wynn C G; Espinoza, Cristóbal M; Antonopoulou, Danai; Andersson, Nils

    2015-10-01

    Pulsars are known for their superb timing precision, although glitches can interrupt the regular timing behavior when the stars are young. These glitches are thought to be caused by interactions between normal and superfluid matter in the crust of the star. However, glitching pulsars such as Vela have been shown to require a superfluid reservoir that greatly exceeds that available in the crust. We examine a model in which glitches tap the superfluid in the core. We test a variety of theoretical superfluid models against the most recent glitch data and find that only one model can successfully explain up to 45 years of observational data. We develop a new technique for combining radio and x-ray data to measure pulsar masses, thereby demonstrating how current and future telescopes can probe fundamental physics such as superfluidity near nuclear saturation. PMID:26601293

  6. Bidirectional transepithelial water transport: measurement and governing mechanisms.

    PubMed Central

    Phillips, J E; Wong, L B; Yeates, D B

    1999-01-01

    In the search for the mechanisms whereby water is transported across biological membranes, we hypothesized that in the airways, the hydration of the periciliary fluid layer is regulated by luminal-to-basolateral water transport coupled to active transepithelial sodium transport. The luminal-to-basolateral (JWL-->B) and the basolateral-to-luminal (JWB-->L) transepithelial water fluxes across ovine tracheal epithelia were measured simultaneously. The JWL-->B (6.1 microliter/min/cm2) was larger than JWB-->L (4.5 microliter/min/cm2, p < 0.05, n = 30). The corresponding water diffusional permeabilities were PdL-->B = 1.0 x 10(-4) cm/s and PdB-->L = 7.5 x 10(-5) cm/s. The activation energy (Ea) of JWL-->B (11.6 kcal/mol) was larger than the Ea of JWB-->L (6.5 kcal/mol, p < 0.05, n = 5). Acetylstrophanthidin (100 microM basolateral) reduced JWL-->B from 6.1 to 4.4 microliter/min/cm2 (p < 0. 05, n = 5) and abolished the PD. Amiloride (10 microM luminal) reduced JWL-->B from 5.7 to 3.7 microliter/min/cm2 (p < 0.05, n = 5) and reduced PD by 44%. Neither of these agents significantly changed JWB-->L. These data indicate that in tracheal epithelia under homeostatic conditions, JWB-->L was dominated by diffusion (Ea = 4.6 kcal/mol), whereas approximately 30% of JWL-->B was coupled to the active Na+,K+-ATPase pump (Ea = 27 kcal/mol). PMID:9929488

  7. A Precision Measurement of the Top Quark Mass

    SciTech Connect

    Black, Kevin Matthew

    2005-01-01

    This dissertation describes the measurement of the top quark mass using events recorded during a ~ 230 pb-1 exposure of the D0 detector to proton-anti-proton (p$\\bar{p}$) collisions at a center of mass energy of 1.96 TeV. The Standard Model of particle physics predicts that the top quark will decay into a bottom quark and a W boson close to 100% of the time. The bottom quark will hadronize (bind with another quark) and produce a jet of hadronic particles. The W bosons can decay either into a charged lepton and a neutrino or a pair of quarks. this dissertation focuses on the top quark (t$\\bar{t}$) events in which one W decays hadronically and the other decays leptonically. Two methods of identifying t$\\bar{t}$ events from the large number of events produced are used. The first is based on the unique topology of the final state particles of a heavy particle. By using the topological information of the event, the t$\\bar{t}$ events can be efficiently extracted from the background. The second method relies on the identification of the remnants of the long lived bottom quarks that are expected to be produced in the decay of almost every top quark. Because the largest background processes do not contain bottom quarks, this is an extremely efficient way to select the events retaining about 60% of the t$\\bar{t}$ events and removing almost 90% of the background. A kinematic fit to the top quark mass is performed on the t$\\bar{t}$ candidate events using the final state particles that are seen in the detector. A likelihood technique is then used to extract the most likely value of the top quark mass, mt, and signal fraction. The result for the topological selection is mt = 169.9 ± 5.8(statistical)$+8.0\\atop{-7.8}$(systematic) GeV while the results on the sample selected from identification of a b quark in the event is mt = 170.6 ± 4.2(statistical)$+6.3\\atop{-6.8}$(systematic) GeV.

  8. Mass-conservative reconstruction of Galerkin velocity fields for transport simulations

    NASA Astrophysics Data System (ADS)

    Scudeler, C.; Putti, M.; Paniconi, C.

    2016-08-01

    Accurate calculation of mass-conservative velocity fields from numerical solutions of Richards' equation is central to reliable surface-subsurface flow and transport modeling, for example in long-term tracer simulations to determine catchment residence time distributions. In this study we assess the performance of a local Larson-Niklasson (LN) post-processing procedure for reconstructing mass-conservative velocities from a linear (P1) Galerkin finite element solution of Richards' equation. This approach, originally proposed for a-posteriori error estimation, modifies the standard finite element velocities by imposing local conservation on element patches. The resulting reconstructed flow field is characterized by continuous fluxes on element edges that can be efficiently used to drive a second order finite volume advective transport model. Through a series of tests of increasing complexity that compare results from the LN scheme to those using velocity fields derived directly from the P1 Galerkin solution, we show that a locally mass-conservative velocity field is necessary to obtain accurate transport results. We also show that the accuracy of the LN reconstruction procedure is comparable to that of the inherently conservative mixed finite element approach, taken as a reference solution, but that the LN scheme has much lower computational costs. The numerical tests examine steady and unsteady, saturated and variably saturated, and homogeneous and heterogeneous cases along with initial and boundary conditions that include dry soil infiltration, alternating solute and water injection, and seepage face outflow. Typical problems that arise with velocities derived from P1 Galerkin solutions include outgoing solute flux from no-flow boundaries, solute entrapment in zones of low hydraulic conductivity, and occurrences of anomalous sources and sinks. In addition to inducing significant mass balance errors, such manifestations often lead to oscillations in concentration

  9. Mass transport in morphogenetic processes: A second gradient theory for volumetric growth and material remodeling

    NASA Astrophysics Data System (ADS)

    Ciarletta, P.; Ambrosi, D.; Maugin, G. A.

    2012-03-01

    In this work, we derive a novel thermo-mechanical theory for growth and remodeling of biological materials in morphogenetic processes. This second gradient hyperelastic theory is the first attempt to describe both volumetric growth and mass transport phenomena in a single-phase continuum model, where both stress- and shape-dependent growth regulations can be investigated. The diffusion of biochemical species (e.g. morphogens, growth factors, migration signals) inside the material is driven by configurational forces, enforced in the balance equations and in the set of constitutive relations. Mass transport is found to depend both on first- and on second-order material connections, possibly withstanding a chemotactic behavior with respect to diffusing molecules. We find that the driving forces of mass diffusion can be written in terms of covariant material derivatives reflecting, in a purely geometrical manner, the presence of a (first-order) torsion and a (second-order) curvature. Thermodynamical arguments show that the Eshelby stress and hyperstress tensors drive the rearrangement of the first- and second-order material inhomogeneities, respectively. In particular, an evolution law is proposed for the first-order transplant, extending a well-known result for inelastic materials. Moreover, we define the first stress-driven evolution law of the second-order transplant in function of the completely material Eshelby hyperstress. The theory is applied to two biomechanical examples, showing how an Eshelbian coupling can coordinate volumetric growth, mass transport and internal stress state, both in physiological and pathological conditions. Finally, possible applications of the proposed model are discussed for studying the unknown regulation mechanisms in morphogenetic processes, as well as for optimizing scaffold architecture in regenerative medicine and tissue engineering.

  10. Coupled porohyperelastic mass transport (PHEXPT) finite element models for soft tissues using ABAQUS.

    PubMed

    Vande Geest, Jonathan P; Simon, B R; Rigby, Paul H; Newberg, Tyler P

    2011-04-01

    Finite element models (FEMs) including characteristic large deformations in highly nonlinear materials (hyperelasticity and coupled diffusive/convective transport of neutral mobile species) will allow quantitative study of in vivo tissues. Such FEMs will provide basic understanding of normal and pathological tissue responses and lead to optimization of local drug delivery strategies. We present a coupled porohyperelastic mass transport (PHEXPT) finite element approach developed using a commercially available ABAQUS finite element software. The PHEXPT transient simulations are based on sequential solution of the porohyperelastic (PHE) and mass transport (XPT) problems where an Eulerian PHE FEM is coupled to a Lagrangian XPT FEM using a custom-written FORTRAN program. The PHEXPT theoretical background is derived in the context of porous media transport theory and extended to ABAQUS finite element formulations. The essential assumptions needed in order to use ABAQUS are clearly identified in the derivation. Representative benchmark finite element simulations are provided along with analytical solutions (when appropriate). These simulations demonstrate the differences in transient and steady state responses including finite deformations, total stress, fluid pressure, relative fluid, and mobile species flux. A detailed description of important model considerations (e.g., material property functions and jump discontinuities at material interfaces) is also presented in the context of finite deformations. The ABAQUS-based PHEXPT approach enables the use of the available ABAQUS capabilities (interactive FEM mesh generation, finite element libraries, nonlinear material laws, pre- and postprocessing, etc.). PHEXPT FEMs can be used to simulate the transport of a relatively large neutral species (negligible osmotic fluid flux) in highly deformable hydrated soft tissues and tissue-engineered materials. PMID:21428686

  11. Transport Measurements on Si Nanostructures with Counted Sb Donors

    NASA Astrophysics Data System (ADS)

    Singh, Meenakshi; Bielejec, Edward; Garratt, Elias; Ten Eyck, Gregory; Bishop, Nathaniel; Wendt, Joel; Luhman, Dwight; Carroll, Malcolm; Lilly, Michael

    2014-03-01

    Donor based spin qubits are a promising platform for quantum computing. Single qubits using timed implant of donors have been demonstrated.1 Extending this to multiple qubits requires precise control over the placement and number of donors. Such control can be achieved by using a combination of low-energy heavy-ion implants (to reduce depth straggle), electron-beam lithography (to define position), focused ion beam (to localize implants to one lithographic site) and counting the number of implants with a single ion detector.2 We report transport measurements on MOS quantum dots implanted with 5, 10 and 20 Sb donors using the approach described above. A donor charge transition is identified by a charge offset in the transport characteristics. Correlation between the number of donors and the charge offsets is studied. These results are necessary first steps towards fabricating donor nanostructures for two qubit interactions. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. The work was supported by Sandia National Laboratories Directed Research and Development Program. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000. 1J. J. Pla et al., Nature 496, 334 (2013) 2J. A. Seamons et al., APL 93, 043124 (2008).

  12. 1. Transport of Mass, Momentum and Energy in Planetary Magnetodisc Regions

    NASA Astrophysics Data System (ADS)

    Achilleos, Nicholas; André, Nicolas; Blanco-Cano, Xochitl; Brandt, Pontus C.; Delamere, Peter A.; Winglee, Robert

    2015-04-01

    The rapid rotation of the gas giant planets, Jupiter and Saturn, leads to the formation of magnetodisc regions in their magnetospheric environments. In these regions, relatively cold plasma is confined towards the equatorial regions, and the magnetic field generated by the azimuthal (ring) current adds to the planetary dipole, forming radially distended field lines near the equatorial plane. The ensuing force balance in the equatorial magnetodisc is strongly influenced by centrifugal stress and by the thermal pressure of hot ion populations, whose thermal energy is large compared to the magnitude of their centrifugal potential energy. The sources of plasma for the Jovian and Kronian magnetospheres are the respective satellites Io (a volcanic moon) and Enceladus (an icy moon). The plasma produced by these sources is globally transported outwards through the respective magnetosphere, and ultimately lost from the system. One of the most studied mechanisms for this transport is flux tube interchange, a plasma instability which displaces mass but does not displace magnetic flux—an important observational constraint for any transport process. Pressure anisotropy is likely to play a role in the loss of plasma from these magnetospheres. This is especially the case for the Jovian system, which can harbour strong parallel pressures at the equatorial segments of rotating, expanding flux tubes, leading to these regions becoming unstable, blowing open and releasing their plasma. Plasma mass loss is also associated with magnetic reconnection events in the magnetotail regions. In this overview, we summarise some important observational and theoretical concepts associated with the production and transport of plasma in giant planet magnetodiscs. We begin by considering aspects of force balance in these systems, and their coupling with the ionospheres of their parent planets. We then describe the role of the interaction between neutral and ionized species, and how it determines

  13. Transport measurements on monolayer and few-layer WSe2

    NASA Astrophysics Data System (ADS)

    Palomaki, Tauno; Zhao, Wenjin; Finney, Joe; Fei, Zaiyao; Nguyen, Paul; McKay, Frank; Cobden, David

    The behavior of the electrical contacts often dominates transport measurements in mono and few-layer transition metal dichalcogenide (TMD) devices. Creating good contacts for some TMDs is particularly challenging since the fabrication procedure should prevent the TMD from oxidizing or chemically interacting with the contacts. In this talk, we discuss our progress on creating mono and few-layer WSe2 devices with both good electrical contacts and minimal effects from the substrate, polymer contamination, oxidation and other chemistry. For example, we have developed a technique for encapsulating metallic contacts and WSe2 flakes together in hexagonal boron nitride with multiple gates to separate and control the contributions from the channel and the Schottky barriers at the contacts. Research supported in part by Samsung GRO grant US 040814

  14. Modelling mass transport through a porous partition: Effect of pore size distribution

    NASA Astrophysics Data System (ADS)

    Khayet, Mohamed; Velázquez, Armando; Mengual, Juan I.

    2004-09-01

    Direct contact membrane distillation process has been studied using microporous polytetrafluoroethylene and polyvinylidene fluoride membranes. The membranes were characterized in terms of their non-wettability, pore size distribution and porosity. The mean pore sizes and pore size distributions were obtained by means of wet/dry flow method. The mean pore size and the effective porosity of the membranes were also determined from the gas permeation test. A theoretical model that considers the pore size distribution together with the gas transport mechanisms through the membrane pores was developed for this process. The contribution of each mass transport mechanism was analyzed. It was found that both membranes have pore size distributions in the Knudsen region and in the transition between Knudsen and ordinary diffusion region. The transition region was the major contribution to mass transport. The predicted water vapor permeability of the membranes were compared with the experimental ones. The effect of considering pore size distribution instead of mean pore size to predict the water vapor permeability of the membranes was investigated.

  15. Measurements of mesospheric aerosol particles during the ECOMA/MASS campaign 2007.

    NASA Astrophysics Data System (ADS)

    Strelnikova, Irina; Rapp, Markus; Strelnikov, Boris; Latteck, Ralph; Baumgarten, Gerd; Brattli, Alvin; Friedrich, Martin; Gumbel, Jorg; Robertson, Scott

    In August 2007 the joint European-American ECOMA/MASS (Existence and Charge state Of Meteoric smoke particles in the middle Atmosphere/Dust MASS Analyzer) sounding rocket and ground-based campaign took place at the Andøya Rocket Range (ARR) (69° N). This campaign was devoted to the investigation of mesospheric aerosol particles. During this campaign, three instrumented sounding rockets were launched under the PMSE and NLC conditions. All rockets were carrying instruments to characterize mesospheric aerosol particles and their environment. The ECOMA rocket was launched during the first salvo shortly (30 min) after the MASS payload. At that time, the EISCAT (69° N, 19° E) VHF and ALWIN radars observed a double layered PMSE. Also an NLC layer was detected by lidar and photometers onboard each rocket. The main instrument of the ECOMA payload is the "ECOMA particle detector". This instrument comprises a classical Faraday cup with a xenon-flash lamp for the active photoionization/photodetachment of mesospheric smoke particles (MSPs) and the subsequent detection of corresponding photoelectrons. Comparing direct Faraday cup measurements and photocurrents we are able to derive particle properties like number densities and particle radii. We present the results of these measurements that show the presence of aerosol particles inside the NLC and PMSE layer, but not below or above these layers. These results are consistent with model predictions, which account for global transport of meteoric smoke. This implies that ice nucleation in the polar summer needs to be reconsidered.

  16. Quantifying energy and mass transfer in crop canopies: sensors for measurement of temperature and air velocity

    NASA Technical Reports Server (NTRS)

    Bugbee, B.; Monje, O.; Tanner, B.

    1996-01-01

    Here we report on the in situ performance of inexpensive, miniature sensors that have increased our ability to measure mass and energy fluxes from plant canopies in controlled environments: 1. Surface temperature. Canopy temperature measurements indicate changes in stomatal aperture and thus latent and sensible heat fluxes. Infrared transducers from two manufacturers (Exergen Corporation, Newton, MA; and Everest Interscience, Tucson, AZ, USA) have recently become available. Transducer accuracy matched that of a more expensive hand-held infrared thermometer. 2. Air velocity varies above and within plant canopies and is an important component in mass and energy transfer models. We tested commercially-available needle, heat-transfer anemometers (1 x 50 mm cylinder) that consist of a fine-wire thermocouple and a heater inside a hypodermic needle. The needle is heated and wind speed determined from the temperature rise above ambient. These sensors are particularly useful in measuring the low wind speeds found within plant canopies. 3. Accurate measurements of air temperature adjacent to plant leaves facilitates transport phenomena modeling. We quantified the effect of radiation and air velocity on temperature rise in thermocouples from 10 to 500 micrometers. At high radiation loads and low wind speeds, temperature errors were as large as 7 degrees C above air temperature.

  17. Quantifying energy and mass transfer in crop canopies: sensors for measurement of temperature and air velocity.

    PubMed

    Bugbee, B; Monje, O; Tanner, B

    1996-01-01

    Here we report on the in situ performance of inexpensive, miniature sensors that have increased our ability to measure mass and energy fluxes from plant canopies in controlled environments: 1. Surface temperature. Canopy temperature measurements indicate changes in stomatal aperture and thus latent and sensible heat fluxes. Infrared transducers from two manufacturers (Exergen Corporation, Newton, MA; and Everest Interscience, Tucson, AZ, USA) have recently become available. Transducer accuracy matched that of a more expensive hand-held infrared thermometer. 2. Air velocity varies above and within plant canopies and is an important component in mass and energy transfer models. We tested commercially-available needle, heat-transfer anemometers (1 x 50 mm cylinder) that consist of a fine-wire thermocouple and a heater inside a hypodermic needle. The needle is heated and wind speed determined from the temperature rise above ambient. These sensors are particularly useful in measuring the low wind speeds found within plant canopies. 3. Accurate measurements of air temperature adjacent to plant leaves facilitates transport phenomena modeling. We quantified the effect of radiation and air velocity on temperature rise in thermocouples from 10 to 500 micrometers. At high radiation loads and low wind speeds, temperature errors were as large as 7 degrees C above air temperature. PMID:11538791

  18. Mass-corrections for the conservative coupling of flow and transport on collocated meshes

    NASA Astrophysics Data System (ADS)

    Waluga, Christian; Wohlmuth, Barbara; Rüde, Ulrich

    2016-01-01

    Buoyancy-driven flow models demand a careful treatment of the mass-balance equation to avoid spurious source and sink terms in the non-linear coupling between flow and transport. In the context of finite-elements, it is therefore commonly proposed to employ sufficiently rich pressure spaces, containing piecewise constant shape functions to obtain local or even strong mass-conservation. In three-dimensional computations, this usually requires nonconforming approaches, special meshes or higher order velocities, which make these schemes prohibitively expensive for some applications and complicate the implementation into legacy code. In this paper, we therefore propose a lean and conservatively coupled scheme based on standard stabilized linear equal-order finite elements for the Stokes part and vertex-centered finite volumes for the energy equation. We show that in a weak mass-balance it is possible to recover exact conservation properties by a local flux-correction which can be computed efficiently on the control volume boundaries of the transport mesh. We discuss implementation aspects and demonstrate the effectiveness of the flux-correction by different two- and three-dimensional examples which are motivated by geophysical applications.

  19. FemtoMolar measurements using accelerator mass spectrometry.

    PubMed

    Salehpour, Mehran; Forsgard, Niklas; Possnert, Göran

    2009-03-01

    Accelerator mass spectrometry (AMS) is an ultra-sensitive analytical method suitable for the detection of sub-nM concentrations of labeled biological substances such as pharmaceutical drugs in body fluids. A limiting factor in extending the concentration measurements to the sub-pM range is the natural (14)C content in living tissues. This was circumvented by separating the labeled drug from the tissue matrix, using standard high-performance liquid chromatography (HPLC) procedures. As the separated total drug amount is in the few fg range, it is not possible to use a standard AMS sample preparation method, where mg sizes are required. We have utilized a sensitive carbon carrier method where a (14)C-deficient compound is added to the HPLC fractions and the composite sample is prepared and analyzed by AMS. Using 50 microL human blood plasma aliquots, we have demonstrated concentration measurements below 20 fM, containing sub-amol amounts of the labeled drug. The method has the immediate potential of operating in the sub-fM region. PMID:19177507

  20. Nanowire dopant measurement using secondary ion mass spectrometry

    SciTech Connect

    Chia, A. C. E.; Boulanger, J. P.; Wood, B. A.; LaPierre, R. R.; Dhindsa, N.; Saini, S. S.

    2015-09-21

    A method is presented to improve the quantitative determination of dopant concentration in semiconductor nanowire (NW) arrays using secondary ion mass spectrometry (SIMS). SIMS measurements were used to determine Be dopant concentrations in a Be-doped GaAs thin film and NW arrays of various pitches that were dry-etched from the same film. A comparison of these measurements revealed a factor of 3 to 12 difference, depending on the NW array pitch, between the secondary Be ion yields of the film and the NW arrays, despite being identically doped. This was due to matrix effects and ion beam mixing of Be from the NWs into the surrounding benzocyclobutene that was used to fill the space between the NWs. This indicates the need for etched NWs to be used as doping standards instead of 2D films when evaluating NWs of unknown doping by SIMS. Using the etched NWs as doping standards, NW arrays of various pitches grown by the vapour-liquid-solid mechanism were characterized by SIMS to yield valuable insights into doping mechanisms.

  1. Atmospheric mass and metal size distributions measured around Lake Michigan

    SciTech Connect

    Seung-Muk Yi; Sofuoglu, S.C.; Holsen, T.M.

    1996-12-31

    This study, which was part of a multi-university AEOLOS investigation, involved an assessment of the spatial and temporal variations in the dry deposition fluxes and mass size distributions (MSDs) of total mass, crustal (aluminum and magnesium), and anthropogenic (lead and copper) metals over the southern basin of Lake Michigan. The work included measurement of deposition fluxes and MSDs during winter, summer and fall, concurrently, in Chicago, IL, over Lake Michigan, and in South Haven, MI. A Cascade impactor was used to determine the size distribution in the fine particles (<2.5 {mu}m), while Noll Rotary Impactor (NRI) was used to collect coarse particles (>2.5 {mu}m). The flux of these metals was substantially higher in Chicago than at either South Haven or over Lake Michigan. The measured average aluminum and magnesium fluxes were 2.23 and 5.32 mg/m{sup 2}-day over Chicago, and 0.24 and 0.28 mg/m{sup 2}-day over Lake Michigan, while the average aluminum and magnesium fluxes in South Haven were 0.17 and 0.12 mg/m{sup 2}-day respectively. The measured average lead and copper fluxes were 0.07 and 0.06 mg/m{sup 2}-day in Chicago, 0.003 and 0.01 mg/m{sup 2}-day over Lake Michigan, and 0.004 and 0.003 mg/m{sup 2}-day in South Haven. This research provided evidence of three possible peaks in the MSDs: the first in the 0-1 {mu}m range, the second in the 1-10 {mu}m region, and the third in the > 10-50 {mu}m range, with the MSDs being unimodal, bimodal or trimodal. Temporal variations in flux were not evident in this study. The wind direction (e.g., from over land, or from over lake) had large impact on both fluxes and size distributions. 5 refs., 10 figs., 1 tab.

  2. Estimation of vertical profiles of wind from MASS measurements

    NASA Astrophysics Data System (ADS)

    Kornilov, Matwey V.

    2012-07-01

    The problem of the wind prole restoration from Multi-Aperture Scintillation Sensor1 (MASS) scintillation indices was studied. We show that we are able to obtain wind proles on the standard MASS altitude grid with reasonable accuracy and altitudinal resolution. Online data processing is also available. Existing MASS data archives can be reprocessed using method of short exposure time.

  3. 3. Mass Movements, Erosion Patterns and Sediment Transport along the Sutlej River (NW-Himalaya)

    NASA Astrophysics Data System (ADS)

    Bookhagen, B.; Thiede, R. C.; Strecker, M. R.

    2003-04-01

    The spatial and temporal distribution of mass movements in active orogens can provide valuable insights into the relation between sedimentation and erosion processes. In areas of high relief, hillslope processes dominate surface geomorphology and can lead to the damming of rivers and formation of lakes upstream. These basins provide a record of natural climatic variations along the river profile and divide the regions in different sedimentational and erosional compartments. To characterize the variations, digital elevation models were used for quantitative analysis of topography, basin-fill volume, and active channel gradients. High-resolution spatial data (digitized 1:25,000 to 1:100,000 topographic maps) and ASTER-derived digital elevation models (DEM) were processed to analyze topography. Combined with geological field measurements and observations we could distinguish erosional patterns within several study areas in the NW Himalayas. Precipitation data were derived from calibrated passive microwave satellite data (SSMI), providing information on a 10 year time series at sufficient spatial resolution (12.5 km2). Modern sediment flux and transport, discharge, geomorphic field observations including river width and slope define the boundary conditions for surface erosion calculations. The Sutlej Valley (32N, 78E) in NW India is dominated by the antecedent Sutlej River, the third-largest river in the Himalayas. It flows perpendicular through the orogen and cuts through all major geologic units of the Tethyan Himalaya, High and Lesser Himalayan Crystallines, and Lower Himalayan units. The geomorphologic changes across thrust faults bounding these units provide valuable insights into the evolution of the orogen. Tectonically active sectors of the orogen are manifested by pronounced knickpoints in longitudinal river profiles that cross active thrust faults. In contrast to other parts of the Himalayas, no (re-) activation of the MCT and STDS can be seen in the

  4. Ozone-surface interactions: Investigations of mechanisms, kinetics, mass transport, and implications for indoor air quality

    SciTech Connect

    Morrison, Glenn C.

    1999-12-01

    In this dissertation, results are presented of laboratory investigations and mathematical modeling efforts designed to better understand the interactions of ozone with surfaces. In the laboratory, carpet and duct materials were exposed to ozone and measured ozone uptake kinetics and the ozone induced emissions of volatile organic compounds. To understand the results of the experiments, mathematical methods were developed to describe dynamic indoor aldehyde concentrations, mass transport of reactive species to smooth surfaces, the equivalent reaction probability of whole carpet due to the surface reactivity of fibers and carpet backing, and ozone aging of surfaces. Carpets, separated carpet fibers, and separated carpet backing all tended to release aldehydes when exposed to ozone. Secondary emissions were mostly n-nonanal and several other smaller aldehydes. The pattern of emissions suggested that vegetable oils may be precursors for these oxidized emissions. Several possible precursors and experiments in which linseed and tung oils were tested for their secondary emission potential were discussed. Dynamic emission rates of 2-nonenal from a residential carpet may indicate that intermediate species in the oxidation of conjugated olefins can significantly delay aldehyde emissions and act as reservoir for these compounds. The ozone induced emission rate of 2-nonenal, a very odorous compound, can result in odorous indoor concentrations for several years. Surface ozone reactivity is a key parameter in determining the flux of ozone to a surface, is parameterized by the reaction probability, which is simply the probability that an ozone molecule will be irreversibly consumed when it strikes a surface. In laboratory studies of two residential and two commercial carpets, the ozone reaction probability for carpet fibers, carpet backing and the equivalent reaction probability for whole carpet were determined. Typically reaction probability values for these materials were 10

  5. Oscillatory Mass Transport in Vapor-Liquid-Solid Growth of Sapphire Nanowires

    SciTech Connect

    Oh, Sang Ho; Chisholm, Matthew F; Kauffmann, Yaron; Kaplan, Prof. Wayne D.; Luo, Weidong; Ruhle, M.; Scheu, Christina

    2010-01-01

    In vapor-liquid-solid (VLS) growth, the liquid phase plays a pivotal role in mediating mass transport from the vapor source to the growth front of a nanowire. Such transport often takes place through the liquid phase. However, we observed by in situ transmission electron microscopy a different behavior for self-catalytic VLS growth of sapphire nanowires. The growth occurs in a layer-by-layer fashion and is accomplished by interfacial diffusion of oxygen through the ordered liquid aluminum atoms. Oscillatory growth and dissolution reactions at the top rim of the nanowires occur and supply the oxygen required to grow a new (0006) sapphire layer. A periodic modulation of the VLS triple-junction configuration accompanies these oscillatory reactions.

  6. Comparison of Flamelet Models with the Transported Mass Fraction Approach for Supersonic Combustion

    NASA Astrophysics Data System (ADS)

    Li, Wenhai; Alabi, Ken; Ladeinde, Foluso

    2015-11-01

    In this study, two fully compressible RANS, LES, and combined RANS/LES flow solvers - AEROFLO and VULCAN, both of which were originally developed by the United States Department of Defense but have since been significantly enhanced and commercialized by our organization, are used to investigate the accuracy of flamelet-based approach when employed to model supersonic combustion. The flamelet results from both codes are assessed relative to solutions obtained by solving the transport equations for the mass fractions - which is also supported by one of the codes, and making familiar assumptions about the closure of the reaction rate. The studies are carried out in the flamelet regime, and the numerical procedures are based on high-order schemes, which are also used to solve the level-set and mixture fraction transport equations used to study, respectively, premixed and non-premixed combustion. The effects of supersonic Mach numbers on the results are discussed.

  7. Lagrangian analysis of mixing and transport of water masses in the marine bays

    NASA Astrophysics Data System (ADS)

    Prants, S. V.; Ponomarev, V. I.; Budyansky, M. V.; Uleysky, M. Yu.; Fayman, P. A.

    2013-01-01

    The Lagrangian approach to studying the mixing and transport of a passive admixture in marine bays and gulfs based on the methods of a theory of dynamic systems is developed. This approach is employed to investigate the lateral mixing and transport of waters in the Peter the Great Bay, Japan Sea, using a velocity field of the predictive numerical hydrodynamic circulation model of a synoptic scale. It is shown that the Lagrangian characteristics, such as the maximum accumulated Lyapunov exponent, the time of particle stay in the bay, particle relative displacements, and the number of cyclonic and anticyclonic rotations, allow us to describe the movement of water masses, the character of mixing, and chaos in the Bay. In integrating the advection equations forward and backward in time, maps showing a number of particle arrivals to different regions of the Bay make it possible to establish corridors through which particles leave and enter the Bay.

  8. Numerical investigation of mass transport through patient-specific deformed aortae.

    PubMed

    Chen, Jie; Gutmark, Ephraim; Mylavarapu, Goutham; Backeljauw, Philippe F; Gutmark-Little, Iris

    2014-01-22

    Blood flow in human arteries has been investigated using computational fluid dynamics tools. This paper considers flow modeling through three aorta models reconstructed from cross-sectional magnetic resonance scans of female patients. One has the normal control configuration, the second has elongation of the transverse aorta, and the third has tortuosity of the aorta with stenosis. The objective of this study is to determine the impact of aortic abnormal geometries on the wall shear stress (WSS), luminal surface low-density lipoproteins (LDLs) concentration, and oxygen flux along the arterial wall. The results show that the curvature of the aortic arch and the stenosis have significant effects on the blood flow, and in turn, the mass transport. The location of hypoxia areas can be predicted well by ignoring the effect of hemoglobin on the oxygen transport. However, this simplification indeed alters the absolute value of Sherwood number on the wall. PMID:24210472

  9. Interfacial and mass transport enhancement effects on rates of styrene epoxidation catalyzed by myoglobin films in microemulsions.

    PubMed

    Vaze, Abhay; Rusling, James F

    2005-01-01

    Biocatalytic surfaces hold promise for future clean methods of chemical synthesis. Biocatalyst films utilizing inexpensive redox proteins can operate in low-toxicity microemulsions with high capacities to dissolve nonpolar reactants. Crosslinked films of myoglobin (Mb) and poly(L-lysine) (PLL) attached to oxidized carbon cathodes gave up to 40-fold larger turnover rates in bicontinuous microemulsions compared to o/w microemulsions and micelles. Larger synthetic turnover rates are correlated with up to 10-fold faster diffusion of solutes in oil phases of the bicontinuous fluids, as measured by voltammetry. Visible and circular dichroism spectra suggest that myoglobin resides in the film in a largely aqueous environment. The reactant sites in films monitored by a fluorescent probe were more polar when films were in CTAB than in SDS microemulsions. These combined results suggest that larger mass transport rates in the bicontinuous fluids is a major factor for enhanced turnover rates. Electrostatic interactions between the charged films and oppositely charged surfactants may significantly influence turnover rates when reactant mass transport is not fast enough.

  10. A mercury transport and fate model (LM2-mercury) for mass budget assessment of mercury cycling in Lake Michigan

    EPA Science Inventory

    LM2-Mercury, a mercury mass balance model, was developed to simulate and evaluate the transport, fate, and biogeochemical transformations of mercury in Lake Michigan. The model simulates total suspended solids (TSS), disolved organic carbon (DOC), and total, elemental, divalent, ...

  11. Neutrino Transport in Black Hole-Neutron Star Binaries: Dynamical Mass Ejection and Neutrino-Driven Wind

    NASA Astrophysics Data System (ADS)

    Kyutoku, K.; Kiuchi, K.; Sekiguchi, Y.; Shibata, M.; Taniguchi, K.

    2016-10-01

    We present our recent results of numerical-relativity simulations of black hole-neutron star binary mergers incorporating approximate neutrino transport. We in particular discuss dynamical mass ejection and neutrino-driven wind.

  12. Mass transport and crystal growth of the mixed ZrS2-ZrSe2 system

    NASA Technical Reports Server (NTRS)

    Wiedemeier, Heribert; Goldman, Howard

    1986-01-01

    The solid solubility of the ZrS2-ZrSe2 system was reinvestigated by annealing techniques to establish the relationship between composition and lattice parameters. Mixed crystals of ZrS(2x)Se2(1-x) for selected compositions of the source material were grown by chemical vapor transport and characterized by X-ray diffraction and microscopic methods. The mass transport rates and crystal growth of ZrSSe were investigated and compared with those of other compositions. The mass fluxes of the mixed system showed an increase with increasing selenium content. The transport products were richer in ZrSe2 than the residual source materials when the ZrSe2 content of the starting materials was greater than 50 mol.-pct. The mass transport rates revealed an increasing mass flux with pressure.

  13. Mass transport-dominated sedimentation in a foreland basin, the Hidaka Trough, northern Japan

    NASA Astrophysics Data System (ADS)

    Noda, Atsushi; TuZino, Taqumi; Joshima, Masato; Goto, Shusaku

    2013-08-01

    Mass transport is an important process of sediment redistribution from shallow to deep sea basins. It is vital to understand this process for disaster prevention and protection of economic interests in coastal and offshore areas. We describe mass transport-dominated sedimentation in an active foreland basin, the Hidaka Trough, which developed from collision between the northeastern Japan arc and the Kuril arc. The basin is deformed by east-west compression associated with large, frequent earthquakes. The trough is filled with thick (>4.5 km) sediments, ranging from coal-bearing Cretaceous terrestrial strata to modern diatomaceous hemipelagic mud and volcanic ash. Bottom-simulating reflectors and the distribution of mud volcanoes, pockmarks, and acoustic wipe-out zones on the seismic records suggest the presence of subsurface gases in the sediments. The basin features stacked mass transport deposits (MTDs), but no channel-levee systems have developed. The MTDs are relatively thin (<30 m) and are derived from three sides of the basin margin. Initiation of submarine slope failure in this area may be controlled by multiple factors that increase driving forces and decrease resistance of the slopes. The driving forces include oversteepening of the margin slope as a resul`t of thrusting and folding, and additional downslope gravitational acceleration caused by cyclic shaking during earthquakes. Decreased resistance in the slopes may be caused by the accumulation of excess pore-water pressure driven by a high-sedimentation rate, gas hydrate dissociation accompanying changes in sea level or seawater temperature, and liquefaction in coarse-grained beds during earthquakes.

  14. Evaluation and optimization of mass transport of redox species in silicon microwire-array photoelectrodes

    PubMed Central

    Xiang, Chengxiang; Meng, Andrew C.; Lewis, Nathan S.

    2012-01-01

    Physical integration of a Ag electrical contact internally into a metal/substrate/microstructured Si wire array/oxide/Ag/electrolyte photoelectrochemical solar cell has produced structures that display relatively low ohmic resistance losses, as well as highly efficient mass transport of redox species in the absence of forced convection. Even with front-side illumination, such wire-array based photoelectrochemical solar cells do not require a transparent conducting oxide top contact. In contact with a test electrolyte that contained 50 mM/5.0 mM of the cobaltocenium+/0 redox species in CH3CN–1.0 M LiClO4, when the counterelectrode was placed in the solution and separated from the photoelectrode, mass transport restrictions of redox species in the internal volume of the Si wire array photoelectrode produced low fill factors and limited the obtainable current densities to 17.6 mA cm-2 even under high illumination. In contrast, when the physically integrated internal Ag film served as the counter electrode, the redox couple species were regenerated inside the internal volume of the photoelectrode, especially in regions where depletion of the redox species due to mass transport limitations would have otherwise occurred. This behavior allowed the integrated assembly to operate as a two-terminal, stand-alone, photoelectrochemical solar cell. The current density vs. voltage behavior of the integrated photoelectrochemical solar cell produced short-circuit current densities in excess of 80 mA cm-2 at high light intensities, and resulted in relatively low losses due to concentration overpotentials at 1 Sun illumination. The integrated wire array-based device architecture also provides design guidance for tandem photoelectrochemical cells for solar-driven water splitting. PMID:22904185

  15. Molecular modeling of surfactant covered oil-water interfaces: Dynamics, microstructure, and barrier for mass transport

    NASA Astrophysics Data System (ADS)

    Gupta, Ashish; Chauhan, Anuj; Kopelevich, Dmitry I.

    2008-06-01

    Mass transport across surfactant-covered oil-water interfaces of microemulsions plays an important role in numerous applications. In the current work, we use coarse-grained molecular dynamics simulations to investigate model systems containing flat hexadecane-water interfaces covered by monolayers of nonionic surfactants of various lengths. Several properties of the surfactant monolayers relevant to the mass transport are considered, including the monolayer microstructure, dynamics, and a free energy barrier to the solute transport. It is observed that the dominant contribution of a surfactant monolayer to the free energy barrier is a steric repulsion caused by a local density increase inside the monolayer. The local densities, and hence the free energy barriers, are larger for monolayers composed of longer surfactants. Since it is likely that the solute transport mechanism involves a sequence of jumps between short-lived pores within a monolayer, we perform a detailed analysis of structure, size, and lifetime of these pores. We demonstrate that the pore statistics is consistent with predictions of percolation theory and apply this theory to identify the characteristic length scale of the monolayer microstructure. The obtained pore structures are sensitive to minute changes of surfactant configurations occurring on the picosecond time scale. To reduce this sensitivity, the pores are averaged over short time intervals. The optimal duration of these time intervals is estimated from analysis of dynamics of pores with diameters comparable to or exceeding the characteristic percolation length scale. The developed approach allows one to filter out transient events of the pore dynamics and to focus on events leading to substantial changes of the monolayer microstructure.

  16. Angular momentum transport efficiency in post-main sequence low-mass stars

    NASA Astrophysics Data System (ADS)

    Spada, F.; Gellert, M.; Arlt, R.; Deheuvels, S.

    2016-05-01

    Context. Using asteroseismic techniques, it has recently become possible to probe the internal rotation profile of low-mass (≈1.1-1.5 M⊙) subgiant and red giant stars. Under the assumption of local angular momentum conservation, the core contraction and envelope expansion occurring at the end of the main sequence would result in a much larger internal differential rotation than observed. This suggests that angular momentum redistribution must be taking place in the interior of these stars. Aims: We investigate the physical nature of the angular momentum redistribution mechanisms operating in stellar interiors by constraining the efficiency of post-main sequence rotational coupling. Methods: We model the rotational evolution of a 1.25M⊙ star using the Yale Rotational stellar Evolution Code. Our models take into account the magnetic wind braking occurring at the surface of the star and the angular momentum transport in the interior, with an efficiency dependent on the degree of internal differential rotation. Results: We find that models including a dependence of the angular momentum transport efficiency on the radial rotational shear reproduce very well the observations. The best fit of the data is obtained with an angular momentum transport coefficient scaling with the ratio of the rotation rate of the radiative interior over that of the convective envelope of the star as a power law of exponent ≈3. This scaling is consistent with the predictions of recent numerical simulations of the Azimuthal Magneto-Rotational Instability. Conclusions: We show that an angular momentum transport process whose efficiency varies during the stellar evolution through a dependence on the level of internal differential rotation is required to explain the observed post-main sequence rotational evolution of low-mass stars.

  17. Clarke Stations and mercurian mass-drivers: energy for large-scale transportation systems

    SciTech Connect

    Jones, E.M.

    1985-01-01

    Three-week voyages across 1 AU could be made in large sailing craft propelled by microwaves generated at power stations operating at 0.1 AU from the sun. The power stations could be built of mercurian materials launched by mass driver to building sites in solar orbit. A Clarke Station 28 km in radius could generate 64 TW of microwaves and support the operation of a 1000-tonne, 1000-passenger vessel. The ability to build near-sun power stations of mercurian materials would not only support high-speed transport but solar system development in general.

  18. Mass estimating techniques for earth-to-orbit transports with various configuration factors and technologies applied

    NASA Technical Reports Server (NTRS)

    Klich, P. J.; Macconochie, I. O.

    1979-01-01

    A study of an array of advanced earth-to-orbit space transportation systems with a focus on mass properties and technology requirements is presented. Methods of estimating weights of these vehicles differ from those used for commercial and military aircraft; the new techniques emphasizing winged horizontal and vertical takeoff advanced systems are described utilizing the space shuttle subsystem data base for the weight estimating equations. The weight equations require information on mission profile, the structural materials, the thermal protection system, and the ascent propulsion system, allowing for the type of construction and various propellant tank shapes. The overall system weights are calculated using this information and incorporated into the Systems Engineering Mass Properties Computer Program.

  19. Measuring hydrodynamics and sediment transport processes in the Dee estuary

    NASA Astrophysics Data System (ADS)

    Bolaños, R.; Souza, A.

    2010-03-01

    The capability of monitoring and predicting the marine environment leads to a more sustainable development of coastal and offshore regions. Therefore, the continuous measurement of environmental processes become an important source of information. The present paper shows data collected during 6 years, and in particular during 2008, in the Dee Estuary. The data aims to improve the observations of the mobile sediments in coastal areas and its forcing hydrodynamics and turbulence. Data involves the deployment of instrumented rigs measuring sediment in suspension, currents, waves, sea level, sediment size and bedforms as well as cruise work including grab sampling, CTD profiles and side-scan sonar. The data covers flood and ebb tides during spring and neap periods with moderate and mild wave events, thus, having a good coverage of the processes needed to improve knowledge of sediment transport and the parameterizations used in numerical modelling. The data, in raw and treated, is being banked at BODC (British Oceanographic Data Centre, http://www.bodc.ac.uk/) which is the formal British organization for looking after and distributing data concerning the marine environment.

  20. Measuring hydrodynamics and sediment transport processes in the Dee Estuary

    NASA Astrophysics Data System (ADS)

    Bolaños, R.; Souza, A.

    2010-06-01

    The capability of monitoring and prediction in the marine environment provides information that may allow sustainable development of coastal and offshore regions. Therefore, the continuous measurement of environmental processes becomes an important source of information. The present paper shows data collected during 6 years, and in particular during 2008, in the Dee Estuary. The aim of the data collection is to improve the observations of the mobile sediments in coastal areas and its forcing hydrodynamics and turbulence. Data includes information from the deployment of instrumented rigs measuring sediment in suspension, currents, waves, sea level, sediment size and bedforms as well as cruise work including grab sampling, CTD profiles and side-scan sonar. The data cover flood and ebb tides during spring and neap periods with moderate and mild wave events, thus, having a good coverage of the processes needed to improve knowledge of sediment transport and the parameterizations used in numerical modelling. The data, in raw and treated, are being banked at BODC (British Oceanographic Data Centre, http://www.bodc.ac.uk/) which is the formal British organization for looking after and distributing data concerning the marine environment.

  1. Extending Penning trap mass measurements with SHIPTRAP to the heaviest elements

    SciTech Connect

    Block, M.; Ackermann, D.; Herfurth, F.; Hofmann, S.; Blaum, K.; Droese, C.; Marx, G.; Schweikhard, L.; Duellmann, Ch. E.; Eibach, M.; Eliseev, S.; Haettner, E.; Plass, W. R.; Scheidenberger, C.; Hessberger, F. P.; Ramirez, E. Minaya; Nesterenko, D.; and others

    2013-03-19

    Penning-trap mass spectrometry of radionuclides provides accurate mass values and absolute binding energies. Such mass measurements are sensitive indicators of the nuclear structure evolution far away from stability. Recently, direct mass measurements have been extended to the heavy elements nobelium (Z=102) and lawrencium (Z=103) with the Penning-trap mass spectrometer SHIPTRAP. The results probe nuclear shell effects at N=152. New developments will pave the way to access even heavier nuclides.

  2. Extending Penning trap mass measurements with SHIPTRAP to the heaviest elements

    NASA Astrophysics Data System (ADS)

    Block, M.; Ackermann, D.; Blaum, K.; Droese, C.; Düllmann, Ch. E.; Eibach, M.; Eliseev, S.; Haettner, E.; Herfurth, F.; Heßberger, F. P.; Hofmann, S.; Marx, G.; Ramirez, E. Minaya; Nesterenko, D.; Novikov, Yu. N.; Plaß, W. R.; Rodríguez, D.; Scheidenberger, C.; Schweikhard, L.; Thirolf, P. G.; Weber, C.

    2013-03-01

    Penning-trap mass spectrometry of radionuclides provides accurate mass values and absolute binding energies. Such mass measurements are sensitive indicators of the nuclear structure evolution far away from stability. Recently, direct mass measurements have been extended to the heavy elements nobelium (Z=102) and lawrencium (Z=103) with the Penning-trap mass spectrometer SHIPTRAP. The results probe nuclear shell effects at N=152. New developments will pave the way to access even heavier nuclides.

  3. Measurements of the conduction-zone length and mass ablation rate in cryogenic direct-drive implosions on OMEGA

    SciTech Connect

    Michel, D. T.; Davis, A. K.; Goncharov, V. N.; Sangster, T. C.; Hu, S. X.; Igumenshchev, I. V.; Meyerhofer, D. D.; Seka, W.; Froula, D. H.

    2015-04-14

    Measurements of the conduction-zone length (110 ± 20 μm at t = 2.8 ns), the averaged mass ablation rate of the deuterated plastic (7.95 ± 0.3 μg/ns), shell trajectory, and laser absorption are made in direct-drive cryogenic implosions and are used to quantify the electron thermal transport through the conduction zone. Hydrodynamic simulations that use nonlocal thermal transport and cross-beam energy transfer models reproduce these experimental observables. Hydrodynamic simulations that use a time-dependent flux-limited model reproduce the measured shell trajectory and the laser absorption but underestimate the mass ablation rate by ~10% and the length of the conduction zone by nearly a factor of 2.

  4. Measurements of the Conduction-Zone Length and Mass Ablation Rate in Cryogenic Direct-Drive Implosions on OMEGA

    NASA Astrophysics Data System (ADS)

    Michel, D. T.; Davis, A. K.; Goncharov, V. N.; Sangster, T. C.; Hu, S. X.; Igumenshchev, I. V.; Meyerhofer, D. D.; Seka, W.; Froula, D. H.

    2015-04-01

    Measurements of the conduction-zone length (110 ±20 μ m at t =2.8 ns ), the averaged mass ablation rate of the deuterated plastic (7.95 ±0.3 μ g /ns ), shell trajectory, and laser absorption are made in direct-drive cryogenic implosions and are used to quantify the electron thermal transport through the conduction zone. Hydrodynamic simulations that use nonlocal thermal transport and cross-beam energy transfer models reproduce these experimental observables. Hydrodynamic simulations that use a time-dependent flux-limited model reproduce the measured shell trajectory and the laser absorption but underestimate the mass ablation rate by ˜10 % and the length of the conduction zone by nearly a factor of 2.

  5. Helium-3 transport experiments in the scrape-off layer with the Alcator C-Mod omegatron ion mass spectrometer

    SciTech Connect

    Nachtrieb, R.; LaBombard, B.

    2000-11-01

    {sup 3}He gas was puffed from the wall into Ohmic low confinement-mode discharges of the Alcator C-Mod [I. H. Hutchinson , Phys. Plasmas 1, 1551 (1994)] tokamak and the charged states were measured near the wall with the omegatron ion mass spectrometer. Analysis of the data shows that the concentrations of singly- and doubly-ionized helium near the wall are approximately equal. The electron temperature and density at the omegatron are too low to account for ionization of helium in the local flux tube, therefore the helium is ionized in a hotter region of the edge plasma and is transported to the omegatron. A simple one-dimensional radial transport model reproduces the observed values of charge state flux and density, but only if rapid cross-field transport is included, increasing with distance from the separatrix. A constant cross-field diffusion coefficient of order 2m{sup 2}/s and an outward convection velocity profile increasing to of order 100 m/s in the far scrape-off layer is implied.

  6. Ballistic thermal transport in monolayer transition-metal dichalcogenides: Role of atomic mass

    NASA Astrophysics Data System (ADS)

    Ma, Jinlong; Li, Wu; Luo, Xiaobing

    2016-02-01

    We investigate the ballistic thermal transport of monolayer transition-metal dichalcogenides (TMDs), which is crucial for the thermal management of their potential applications in nanoelectronics. We find the thermal conductance is mainly affected by the atomic masses of TMDs. As a consequence, the temperature dependences of thermal conductances of different TMDs cross: At low temperatures below ˜50 K, the thermal conductance increases with the atomic mass, while it exhibits the opposite trend at high temperatures. The crossing behavior of temperature dependent thermal conductance is characteristic of the atomic mass effect, and TMDs provide a model system demonstrating that the thermal conductance can be effectively manipulated via the atomic mass by selecting appropriate atom. In addition, we clarify that in any two dimensional system such as monolayer TMDs and graphene, due to quadratic dispersion of the out-of-plane modes, the thermal conductance and specific heat in the low temperature limit are proportional to T3/2 and T, respectively. Mainly because of much smaller group velocities of in-plane acoustic phonons, the high temperature thermal conductances of monolayer TMDs are much smaller than graphene. However, due to comparable group velocities of out-of-plane acoustic phonons, below 100 K thermal conductances of monolayer TMDs are rather comparable to graphene if taking the same layer thickness for comparison.

  7. Flux dependent MeV self-ion-induced effects on Au nanostructures: dramatic mass transport and nanosilicide formation.

    PubMed

    Ghatak, J; Umananda Bhatta, M; Sundaravel, B; Nair, K G M; Liou, Sz-Chian; Chen, Cheng-Hsuan; Wang, Yuh-Lin; Satyam, P V

    2008-08-13

    We report a direct observation of dramatic mass transport due to 1.5 MeV Au(2+) ion impact on isolated Au nanostructures of average size ≈7.6 nm and height ≈6.9 nm that are deposited on Si(111) substrate under high flux (3.2 × 10(10)-6.3 × 10(12) ions cm(-2) s(-1)) conditions. The mass transport from nanostructures was found to extend up to a distance of about 60 nm into the substrate, much beyond their size. This forward mass transport is compared with the recoil implantation profiles using SRIM simulation. The observed anomalies with theory and simulations are discussed. At a given energy, the incident flux plays a major role in mass transport and its redistribution. The mass transport is explained on the basis of thermal effects and the creation of rapid diffusion paths in the nanoscale regime during the course of ion irradiation. The unusual mass transport is found to be associated with the formation of gold silicide nano-alloys at subsurfaces. The complexity of the ion-nanostructure interaction process is discussed with a direct observation of melting (in the form of spherical fragments on the surface) phenomena. Transmission electron microscopy, scanning transmission electron microscopy, and Rutherford backscattering spectroscopy methods have been used.

  8. Measuring the neutral hydrogen mass of galaxy cluster A262

    NASA Astrophysics Data System (ADS)

    Hassan, Mohd Shaiful Rizal; Abidin, Zamri Zainal; Ibrahim, Zainol Abidin; Ibrahim, Ungku Ferwani Salwa Ungku; Hashim, Norsiah

    2013-05-01

    The total neutral hydrogen mass of galaxy cluster, MHI is measured using spectra taken by a 7 meter single dish radio telescope at Jodrell Bank Observatory. This have been done by using a concept introduced by R. A. Bettye which is make use of small single radio telescope for findings MHI as a whole. MHI is calculated by using simple relationship involving parameter distance of the object from the observer, D and radiated flux of continuum radio source, Sν. A262 is chosen as our test subject since it is compatible with the capability of our instrument. It is a spiral rich galaxy cluster and a fragment of Pisces in the Perseus supercluster, located approximately at 62 - 77 Mpc. It is a part of Local Group Supercluster that is centered at giant elliptical galaxy, NGC 708, and it is also called `cluster dominant' because of its strongly X-ray source concentrated. A262 is chosen as our candidate in this study because of its relatively low redshift, z = 0.0156, observed in 21 cm emission as their tracer. We calculate MHI of A262 according to some analysis from previous studies. Preliminary detection of A262 showed some degree of success.

  9. Device for accurately measuring mass flow of gases

    DOEpatents

    Hylton, James O.; Remenyik, Carl J.

    1994-01-01

    A device for measuring mass flow of gases which utilizes a substantially buoyant pressure vessel suspended within a fluid/liquid in an enclosure. The pressure vessel is connected to a weighing device for continuously determining weight change of the vessel as a function of the amount of gas within the pressure vessel. In the preferred embodiment, this pressure vessel is formed from inner and outer right circular cylindrical hulls, with a volume between the hulls being vented to the atmosphere external the enclosure. The fluid/liquid, normally in the form of water typically with an added detergent, is contained within an enclosure with the fluid/liquid being at a level such that the pressure vessel is suspended beneath this level but above a bottom of the enclosure. The buoyant pressure vessel can be interconnected with selected valves to an auxiliary pressure vessel so that initial flow can be established to or from the auxiliary pressure vessel prior to flow to or from the buoyant pressure vessel.

  10. Device for accurately measuring mass flow of gases

    DOEpatents

    Hylton, J.O.; Remenyik, C.J.

    1994-08-09

    A device for measuring mass flow of gases which utilizes a substantially buoyant pressure vessel suspended within a fluid/liquid in an enclosure is disclosed. The pressure vessel is connected to a weighing device for continuously determining weight change of the vessel as a function of the amount of gas within the pressure vessel. In the preferred embodiment, this pressure vessel is formed from inner and outer right circular cylindrical hulls, with a volume between the hulls being vented to the atmosphere external the enclosure. The fluid/liquid, normally in the form of water typically with an added detergent, is contained within an enclosure with the fluid/liquid being at a level such that the pressure vessel is suspended beneath this level but above a bottom of the enclosure. The buoyant pressure vessel can be interconnected with selected valves to an auxiliary pressure vessel so that initial flow can be established to or from the auxiliary pressure vessel prior to flow to or from the buoyant pressure vessel. 5 figs.

  11. A new approach to mass spectrometer measurements of thermospheric density

    NASA Technical Reports Server (NTRS)

    Melfi, L. T., Jr.; Brock, F. J.; Brown, C. A., Jr.

    1974-01-01

    The gas sampling problem in satellite and high velocity probes was investigated by applying the theory of a drifting Maxwellian gas. A lens system using a free stream ion source was developed and experimentally evaluated over the pressure range of 0.00001 to 0.01 N/m sq (approx. 10 to the minus 7th power to 0.0001 torr). The source has high beam transparency, which minimizes gas-surface collisions within, or near, the ionization volume. It is shown that for high ion energy (60 eV), the extracted ion beam has an on-axis energy spread of less than 4 eV, and that 90 percent of the ions are within 2.5 deg of the beam axis. It is concluded that the molecular beam mass spectrometer concept, developed for gas density measurements in the upper atmosphere, substantially reduces gas-surface scattering and gas-surface reactions in the sample, and preserves the integrity of the gas sample during the analysis process. Studies show that both the Scout and Delta launch vehicles have adequate volume, control, velocity, and data acquisition capability necessary to obtain thermospheric number density in real time.

  12. Measurement of the dipion mass spectrum in decays.

    PubMed

    Abulencia, A; Acosta, D; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arguin, J-F; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Belloni, A; Ben Haim, E; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Bourov, S; Boveia, A; Brau, B; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carlsmith, D; Carosi, R; Carron, S; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chapman, J; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Chu, P H; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciljak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Connolly, A; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Cruz, A; Cuevas, J; Culbertson, R; Cyr, D; Daronco, S; D'Auria, S; D'onofrio, M; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; Dell'orso, M; Demers, S; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Dionisi, C; Dittmann, J R; DiTuro, P; Dörr, C; Dominguez, A; Donati, S; Donega, M; Dong, P; Donini, J; Dorigo, T; Dube, S; Ebina, K; Efron, J; Ehlers, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J C; Fujii, Y; Furic, I; Gajjar, A; Gallinaro, M; Galyardt, J; Garcia, J E; Garcia Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerchtein, E; Gerdes, D; Giagu, S; di Giovanni, G P; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giokaris, N; Giolo, K; Giordani, M; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Gresele, A; Griffiths, M; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Haber, C; Hahn, S R; Hahn, K; Halkiadakis, E; Hamilton, A; Han, B-Y; Handler, R; Happacher, F; Hara, K; Hare, M; Harper, S; Harr, R F; Harris, R M; Hatakeyama, K; Hauser, J; Hays, C; Hayward, H; Heijboer, A; Heinemann, B; Heinrich, J; Hennecke, M; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Huston, J; Ikado, K; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jensen, H; Jeon, E J; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kamon, T; Kang, J; Karagoz-Unel, M; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, M S; Kim, S B; Kim, S H; Kim, Y K; Kirby, M; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kobayashi, H; Kondo, K; Kong, D J; Konigsberg, J; Kordas, K; Korytov, A; Kotwal, A V; Kovalev, A; Kraus, J; Kravchenko, I; Kreps, M; Kreymer, A; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; Lecci, C; Lecompte, T; Lee, J; Lee, J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Li, K; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Liss, T M; Lister, A; Litvintsev, D O; Liu, T; Liu, Y; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Maksimovic, P; Manca, G; Margaroli, F; Marginean, R; Marino, C; Martin, A; Martin, M; Martin, V; Martínez, M; Maruyama, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McGivern, D; McIntyre, P; McNamara, P; McNulty, R; Mehta, A; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; von der Mey, M; Miao, T; Miladinovic, N; Miles, J; Miller, R; Miller, J S; Mills, C; Milnik, M; Miquel, R; Miscetti, S; Mitselmakher, G; Miyamoto, A; Moggi, N; Mohr, B; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Mulhearn, M; Muller, Th; Mumford, R; Murat, P; Nachtman, J; Nahn, S; Nakano, I; Napier, A; Naumov, D; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nigmanov, T; Nodulman, L; Norniella, O; Ogawa, T; Oh, S H; Oh, Y D; Okusawa, T; Oldeman, R; Orava, R; Osterberg, K; Pagliarone, C; Palencia, E; Paoletti, R; Papadimitriou, V; Papikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pitts, K; Plager, C; Pondrom, L; Pope, G; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Rakitin, A; Rappoccio, S; Ratnikov, F; Reisert, B; Rekovic, V; van Remortel, N; Renton, P; Rescigno, M; Richter, S; Rimondi, F; Rinnert, K; Ristori, L; Robertson, W J; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Rott, C; Ruiz, A; Russ, J; Rusu, V; Ryan, D; Saarikko, H; Sabik, S; Safonov, A; Sakumoto, W K; Salamanna, G; Salto, O; Saltzberg, D; Sanchez, C; Santi, L; Sarkar, S; Sato, K; Savard, P; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Semeria, F; Sexton-Kennedy, L; Sfiligoi, I; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sill, A; Sinervo, P; Sisakyan, A; Sjolin, J; Skiba, A; Slaughter, A J; Sliwa, K; Smirnov, D; Smith, J R; Snider, F D; Snihur, R; Soderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Squillacioti, P; Stanitzki, M; Staveris-Polykalas, A; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sumorok, K; Sun, H; Suzuki, T; Taffard, A; Tafirout, R; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Tether, S; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Tönnesmann, M; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tsuchiya, R; Tsuno, S; Turini, N; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vacavant, L; Vaiciulis, A; Vallecorsa, S; Varganov, A; Vataga, E; Velev, G; Veramendi, G; Veszpremi, V; Vickey, T; Vidal, R; Vila, I; Vilar, R; Vollrath, I; Volobouev, I; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wallny, R; Walter, T; Wan, Z; Wang, M J; Wang, S M; Warburton, A; Ward, B; Waschke, S; Waters, D; Watts, T; Weber, M; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Worm, S; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zetti, F; Zhang, X; Zhou, J; Zucchelli, S

    2006-03-17

    We measure the dipion mass spectrum in X(3872)--> J/psipi(+) pi(-) decays using 360 pb(-1) of pp collisions at square root s= 1.96 TeV collected with the CDF II detector. The spectrum is fit with predictions for odd C-parity ((3)S(1), (1)P(1), and (3)D(J)) charmonia decaying to J/psipi(+) pi(-), as well as even C-parity states in which the pions are from rho(0) decay. The latter case also encompasses exotic interpretations, such as a D(0)D(*0) molecule. Only the (3)S(1) and J/psirho hypotheses are compatible with our data. Since (3)S(1) is untenable on other grounds, decay via J/psirho is favored, which implies C= +1 for the X(3872). Models for J/psi - rho different angular momenta L are considered. Flexibility in the models, especially the introduction of rho - omega interference, enables good descriptions of our data for both L = 0 and 1.

  13. Mass flow and its pulsation measurements in supersonic wing wake

    NASA Astrophysics Data System (ADS)

    Shmakov, A. S.; Shevchenko, A. M.; Yatskikh, A. A.; Yermolaev, Yu. G.

    2016-10-01

    The results of experimental study of the flow in the wing wake are presented. Experiments were carried out in supersonic wind tunnel T-325 of ITAM SB RAS. Rectangle half-wing with sharp edges with a chord length of 30 mm and semispan of 95 mm was used to generate vortex wake. Experimental data were obtained in the cross section located 6 chord length downstream of the trailing edge at Mach numbers of 2.5 and 4 and at wing angles of attack of 4 and 10 degrees. Constant temperature hot-wire anemometer was used to measure disturbances in supersonic flow. Hot-wire was made of a tungsten wire with a diameter of 10 μm and length of 1.5 mm. Shlieren flow visualization were performed. As a result, the position and size of the vortex core in the wake of a rectangular wing were determined. For the first time experimental data on the mass flow distribution and its pulsations in the supersonic longitudinal vortex were obtained.

  14. Measurement of the dipion mass spectrum in decays.

    PubMed

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    2006-03-17

    We measure the dipion mass spectrum in X(3872)--> J/psipi(+) pi(-) decays using 360 pb(-1) of pp collisions at square root s= 1.96 TeV collected with the CDF II detector. The spectrum is fit with predictions for odd C-parity ((3)S(1), (1)P(1), and (3)D(J)) charmonia decaying to J/psipi(+) pi(-), as well as even C-parity states in which the pions are from rho(0) decay. The latter case also encompasses exotic interpretations, such as a D(0)D(*0) molecule. Only the (3)S(1) and J/psirho hypotheses are compatible with our data. Since (3)S(1) is untenable on other grounds, decay via J/psirho is favored, which implies C= +1 for the X(3872). Models for J/psi - rho different angular momenta L are considered. Flexibility in the models, especially the introduction of rho - omega interference, enables good descriptions of our data for both L = 0 and 1. PMID:16605726