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Sample records for grade decay heat

  1. Decay heat studies for nuclear energy

    NASA Astrophysics Data System (ADS)

    Algora, A.; Jordan, D.; Taín, J. L.; Rubio, B.; Agramunt, J.; Caballero, L.; Nácher, E.; Perez-Cerdan, A. B.; Molina, F.; Estevez, E.; Valencia, E.; Krasznahorkay, A.; Hunyadi, M. D.; Gulyás, J.; Vitéz, A.; Csatlós, M.; Csige, L.; Eronen, T.; Rissanen, J.; Saastamoinen, A.; Moore, I. D.; Penttilä, H.; Kolhinen, V. S.; Burkard, K.; Hüller, W.; Batist, L.; Gelletly, W.; Nichols, A. L.; Yoshida, T.; Sonzogni, A. A.; Peräjärvi, K.

    2014-01-01

    The energy associated with the decay of fission products plays an important role in the estimation of the amount of heat released by nuclear fuel in reactors. In this article we present results of the study of the beta decay of some refractory isotopes that were considered important contributors to the decay heat in reactors. The measurements were performed at the IGISOL facility of the University of Jyväskylä, Finland. In these studies we have combined for the first time a Penning trap (JYFLTRAP), which was used as a high resolution isobaric separator, with a total absorption spectrometer. The results of the measurements as well as their consequences for decay heat summation calculations are discussed.

  2. Nitinol engine for low grade heat

    SciTech Connect

    Li, Y.T.

    1981-12-01

    A continuous band of nitinol wrapping in between a cluster of tightly engaged rollers to form a series of s-shaped bends is used as the principle working medium of a thermal engine to convert low grade heat to mechanical power output. The band, together with the rollers, divides the space into an inner and an outer zone. A stream of warmer water and a stream of cooler water are guided to flow separately through one or the other of the two zones to make uniform and intimate contact with the segments of the nitinol band alternatively at appropriate intervals. A well defined four-cycle operation of temperature and stress is thus established and can convert a portion of the energy which is available in the thermal gradient of the two water streams into a mechanical shaft power which may be tapped from one of the rollers.

  3. Monticello BWR spent fuel assembly decay heat predictions and measurements

    SciTech Connect

    McKinnon, M.A.; Doman, J.W.; Heeb, C.M.; Creer, J.M.

    1986-06-01

    This report compares pre-calorimetry predictions of rates of six 7 x 7 boiling water reactor (BWR) spent fuel assemblies with measured decay heat rates. The assemblies were from Northern States Power Company's Monticello Nuclear Generating Plant and had burnups of 9 to 21 GWd/MTU and cooling times of 9 to 10 years. Conclusions are: The agreement between ORIGEN2 predictions and decay heat measurements of Monticello spent fuel is dependent on the method used to calibrate the calorimeter and to make the decay heat measurements. The agreement between predictions and measurements of decay heat rates of Monticello fuel is the same as that for Cooper and Dresden fuel if the same measurement method is used. The predictions are within a standard deviation of +-15 W of the measurements. Using a different measurement method, ORIGEN2 underpredicts the measured decay heat output of Monticello fuel assemblies by a constant 20 +- 2 W. The 20-W offset appears to be an artifact of the calibration procedure. The constant term in the calibration curve (i.e., q/sub DH/ = mx + b) can account for measurement differences of 40 W based on the 1983, 1984, and 1985 calibration curves. The difference between ORIGEN2 predictions and calorimeter decay heat measurements does not appear to be dependent on the magnitude of decay heat output. Predicted axial decay heat profiles are in good agreement with measured axial gamma radiation profiles. Recommendations are: Predictions using other decay heat codes should be compared to experimental data contained in this report, to evaluate prediction capabilities. The source of the differences that exist among calorimeter calibration curves needs to be determined. Calorimeter operational methods need to be investigated further to determine cause and effect relationships between operational method and calorimeter precision and accuracy.

  4. Thermal-hydraulic investigations of the European Fast Reactor DHR (decay heat removal) system

    SciTech Connect

    Dueweke, M.; Friedel, G.; Friedrich, H.J. ); Azarian, G. ); Thomasson, R.K. )

    1989-11-01

    With the framework of the European Fast Reactor (EFR) program, a 2-yr conceptual design study was launched in spring 1988. One major area of investigation is the decay heat removal (DHR) following a reactor trip, when the steam plant heat sink is unavailable. Decay heat will be removed from the primary sodium by a safety-grade direct rector cooling system (DRCS), which should be as independent from the emergency power supply as possible. At present, the DRCS for EFR features three identical sodium loops, each with a 30-MW rating, operating in natural circulation under all circumstances. Each loop consists of a sodium/sodium heat-exchanging U-tube dip cooler and a sodium/air heat exchanger (AHX). The thermohydraulic behavior was studied with the one-dimensional system code DYANA and with the two-dimensional thermohydraulic code ATTICA.

  5. Desalination using low grade heat sources

    NASA Astrophysics Data System (ADS)

    Gude, Veera Gnaneswar

    A new, low temperature, energy-efficient and sustainable desalination system has been developed in this research. This system operates under near-vacuum conditions created by exploiting natural means of gravity and barometric pressure head. The system can be driven by low grade heat sources such as solar energy or waste heat streams. Both theoretical and experimental studies were conducted under this research to evaluate and demonstrate the feasibility of the proposed process. Theoretical studies included thermodynamic analysis and process modeling to evaluate the performance of the process using the following alternate energy sources for driving the process: solar thermal energy, solar photovoltaic/thermal energy, geothermal energy, and process waste heat emissions. Experimental studies included prototype scale demonstration of the process using grid power as well as solar photovoltaic/thermal sources. Finally, the feasibility of the process in reclaiming potable-quality water from the effluent of the city wastewater treatment plant was studied. The following results have been obtained from theoretical analysis and modeling: (1) The proposed process can produce up to 8 L/d of freshwater for 1 m2 area of solar collector and evaporation chamber respectively with a specific energy requirement of 3122 kJ for 1 kg of freshwater production. (2) Photovoltaic/thermal (PV/T) energy can produce up to 200 L/d of freshwater with a 25 m2 PV/T module which meets the electricity needs of 21 kWh/d of a typical household as well. This configuration requires a specific energy of 3122 kJ for 1 kg of freshwater production. (3) 100 kg/hr of geothermal water at 60°C as heat source can produce up to 60 L/d of freshwater with a specific energy requirement of 3078 kJ for 1 kg of freshwater production. (4) Waste heat released from an air conditioning system rated at 3.25 kW cooling, can produce up to 125 L/d of freshwater. This configuration requires an additional energy of 208 kJ/kg of

  6. Development of optimized, graded-permeability axial groove heat pipes

    NASA Technical Reports Server (NTRS)

    Kapolnek, Michael R.; Holmes, H. Rolland

    1988-01-01

    Heat pipe performance can usually be improved by uniformly varying or grading wick permeability from end to end. A unique and cost effective method for grading the permeability of an axial groove heat pipe is described - selective chemical etching of the pipe casing. This method was developed and demonstrated on a proof-of-concept test article. The process improved the test article's performance by 50 percent. Further improvement is possible through the use of optimally etched grooves.

  7. Decay Heat Measurements Using Total Absorption Gamma-ray Spectroscopy

    NASA Astrophysics Data System (ADS)

    Rice, S.; Valencia, E.; Algora, A.; Taín, J. L.; Regan, P. H.; Podolyák, Z.; Agramunt, J.; Gelletly, W.; Nichols, A. L.

    2012-09-01

    A knowledge of the decay heat emitted by thermal neutron-irradiated nuclear fuel is an important factor in ensuring safe reactor design and operation, spent fuel removal from the core, and subsequent storage prior to and after reprocessing, and waste disposal. Decay heat can be readily calculated from the nuclear decay properties of the fission products, actinides and their decay products as generated within the irradiated fuel. Much of the information comes from experiments performed with HPGe detectors, which often underestimate the beta feeding to states at high excitation energies. This inability to detect high-energy gamma emissions effectively results in the derivation of decay schemes that suffer from the pandemonium effect, although such a serious problem can be avoided through application of total absorption γ-ray spectroscopy (TAS). The beta decay of key radionuclei produced as a consequence of the neutron-induced fission of 235U and 239Pu are being re-assessed by means of this spectroscopic technique. A brief synopsis is given of the Valencia-Surrey (BaF2) TAS detector, and their method of operation, calibration and spectral analysis.

  8. Decay heat fractions for DFA 8213 and 4192

    SciTech Connect

    Kessler, S.F., Fluor Daniel Hanford

    1997-02-06

    Decay heat fractions for FFTF driver fuel assemblies 8213 and 4192 were calculated to allow the assembly nozzles to be cut. Cutting the nozzles is required to allow the assemblies to fit in the center location of a core component container in an Interim Storage Cask.

  9. Computer program grade for design and analysis of graded-porosity heat-pipe wicks

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.

    1974-01-01

    A computer program for numerical solution of differential equations that describe heat pipes with graded-porosity fibrous wicks is discussed. A mathematical problem is provided with a summary of the input and output steps used to solve it. The program is also applied to the analysis of a typical heat pipe.

  10. Graded-porosity heat-pipe wicks

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.

    1976-01-01

    To maximize the capacity of a nonarterial heat pipe, a wick is considered whose porosity is allowed to vary axially along its length. At every axial location the porosity is set no lower than required to maintain the wick in a nearly saturated state under the maximum heat-transport rate. The result is a wick whose permeability is everywhere as high as possible. The differential equation that governs the optimum porosity variation is solved numerically between a condenser-end boundary condition that just prevents a liquid slug or puddle in the vapor spaces and an evaporator-end boundary condition that just prevents circumferential groove dry-up. Experimental performance measurements for an ammonia heat pipe are presented.

  11. ICRF heating in reactor grade plasmas

    SciTech Connect

    Jacquinot, J.; Bhatnagar, V.P.; Bures, M.; Cottrell, G.A.; Eriksson, L.G.; Sack, C.H.; Start, D.F.H.; Taroni, A. ); Hellsten, T. ); Koch, R. ); Moreau, D. )

    1990-01-01

    Impurity influxes in JET discharges due to ICRH have been reduced to insignificant levels. This has allowed high quality H-modes to be produced with ICRH alone and has enhanced the density limit which is now the same as the NBI limit. Improvement in the deuterium fuel fraction has led to the generation of 100kW of non thermal {sup 3}He-D fusion power. Alpha-particle simulations using MeV ions created by ICRH show classical energy loss and suggest that {alpha}-heating in a reactor will be highly efficient. A clear demonstration of TTMP damping of the fast wave in high beta plasmas has been achieved. A broadband ICRH system is proposed for NET/ITER which will allow fast wave current drive and central ion heating for burn control and ignition. 10 refs., 6 figs.

  12. Decay heat removal in GEN IV gas cooled fast reactors.

    SciTech Connect

    Cheng, L. Y.; Wei, T. Y. C.

    2009-08-01

    The safety goal of the current designs of advanced high-temperature thermal gas-cooled reactors (HTRs) is that no core meltdown would occur in a depressurization event with a combination of concurrent safety system failures. This study focused on the analysis of passive decay heat removal (DHR) in a GEN IV direct-cycle gas-cooled fast reactor (GFR) which is based on the technology developments of the HTRs. Given the different criteria and design characteristics of the GFR, an approach different from that taken for the HTRs for passive DHR would have to be explored. Different design options based on maintaining core flow were evaluated by performing transient analysis of a depressurization accident using the system code RELAP5-3D. The study also reviewed the conceptual design of autonomous systems for shutdown decay heat removal and recommends that future work in this area should be focused on the potential for Brayton cycle DHRs.

  13. Castor-1C spent fuel storage cask decay heat, heat transfer, and shielding analyses

    SciTech Connect

    Rector, D.R.; McCann, R.A.; Jenquin, U.P.; Heeb, C.M.; Creer, J.M.; Wheeler, C.L.

    1986-12-01

    This report documents the decay heat, heat transfer, and shielding analyses of the Gesellschaft fuer Nuklear Services (GNS) CASTOR-1C cask used in a spent fuel storage demonstration performed at Preussen Elektra's Wurgassen nuclear power plant. The demonstration was performed between March 1982 and January 1984, and resulted in cask and fuel temperature data and cask exterior surface gamma-ray and neutron radiation dose rate measurements. The purpose of the analyses reported here was to evaluate decay heat, heat transfer, and shielding computer codes. The analyses consisted of (1) performing pre-look predictions (predictions performed before the analysts were provided the test data), (2) comparing ORIGEN2 (decay heat), COBRA-SFS and HYDRA (heat transfer), and QAD and DOT (shielding) results to data, and (3) performing post-test analyses if appropriate. Even though two heat transfer codes were used to predict CASTOR-1C cask test data, no attempt was made to compare the two codes. The codes are being evaluated with other test data (single-assembly data and other cask data), and to compare the codes based on one set of data may be premature and lead to erroneous conclusions.

  14. Effect of yeast antagonist in combination with heat treatment on postharvest blue mold decay and Rhizopus decay of peaches.

    PubMed

    Zhang, Hongyin; Wang, Lei; Zheng, Xiaodong; Dong, Ying

    2007-04-01

    The potential of using heat treatment alone or in combination with an antagonistic yeast for the control of blue mold decay and Rhizopus decay of peaches caused by Penicillium expansum and Rhizopus stolonifer respectively, and in reducing natural decay development of peach fruits, as well as its effects on postharvest quality of fruit was investigated. In vitro tests, spore germination of pathogens in PDB was greatly controlled by the heat treatment of 37 degrees C for 2 d. In vivo test to control blue mold decay of peaches, heat treatment and antagonist yeast, as stand-alone treatments, were capable of reducing the percentage of infected wounds from 92.5% to 52.5% and 62.5%, respectively, when peach fruits stored at 25 degrees C for 6 d. However, in fruit treated with combination of heat treatment and Cryptococcus laurentii, the percentage of infected wounds of blue mold decay was only 22.5%. The test of using heat treatment alone or in combination with C. laurentii to control Rhizopus decay of peaches gave a similar result. The application of heat treatment and C. laurentii resulted in low average natural decay incidences on peaches after storage at 4 degrees C for 30 days and 20 degrees C for 7 days ranging from 40% to 30%, compared with 20% in the control fruit. The combination of heat treatment and C. laurentii was the most effective treatment, and the percentage of decayed fruits was 20%. Heat treatment in combination with C. laurentii had no significant effect on firmness, TSS, ascorbic acid or titratable acidity compared to control fruit. Thus, the combination of heat treatment and C. laurentii could be an alternative to chemicals for the control of postharvest decay on peach fruits. PMID:17140691

  15. Low-grade heat recuperation by the organic Rankine cycle

    NASA Astrophysics Data System (ADS)

    Verneau, A.

    1980-11-01

    The use of an organic Rankine cycle engine in the conversion of low-grade industrial waste heat into mechanical energy is examined. The principles of a Rankine system using a vapor as the working fluid at operating temperatures from 100 to 500 C are presented, and the advantages of using organic vapors rather than water in the Rankine cycle are pointed out. Attention is then given to the Rankine cycle itself, the organic fluids employed, the multistage low-power turbines and the evaporator, which acts as a countercurrent heat exchanger. Economic aspects of the use of Rankine cycle systems for industrial waste heat recovery are then considered, and examples are presented of the calculation of power recovered and investment costs for the examples of heat recovery from diesel exhaust and from low-pressure steam.

  16. Gas-Cooled Fast Reactor (GFR) Decay Heat Removal Concepts

    SciTech Connect

    K. D. Weaver; L-Y. Cheng; H. Ludewig; J. Jo

    2005-09-01

    Current research and development on the Gas-Cooled Fast Reactor (GFR) has focused on the design of safety systems that will remove the decay heat during accident conditions, ion irradiations of candidate ceramic materials, joining studies of oxide dispersion strengthened alloys; and within the Advanced Fuel Cycle Initiative (AFCI) the fabrication of carbide fuels and ceramic fuel matrix materials, development of non-halide precursor low density and high density ceramic coatings, and neutron irradiation of candidate ceramic fuel matrix and metallic materials. The vast majority of this work has focused on the reference design for the GFR: a helium-cooled, direct power conversion system that will operate with an outlet temperature of 850ºC at 7 MPa. In addition to the work being performed in the United States, seven international partners under the Generation IV International Forum (GIF) have identified their interest in participating in research related to the development of the GFR. These are Euratom (European Commission), France, Japan, South Africa, South Korea, Switzerland, and the United Kingdom. Of these, Euratom (including the United Kingdom), France, and Japan have active research activities with respect to the GFR. The research includes GFR design and safety, and fuels/in-core materials/fuel cycle projects. This report is a compilation of work performed on decay heat removal systems for a 2400 MWt GFR during this fiscal year (FY05).

  17. Grouping of light water reactors for evaluation of decay heat removal capability

    SciTech Connect

    Karol, R.; Fresco, A.; Perkins, K.R.

    1984-06-01

    This grouping report provides a compilation of decay heat removal systems (DHRS) data for operating commercial light water reactors. The reactors have been divided into 12 groups based on similarity of the DHRS and related systems as part of the NRC Task Action Plan on Shutdown Decay Heat Removal Requirements.

  18. Mixed-oxide fuel decay heat analysis for BWR LOCA safety evaluation

    SciTech Connect

    Chiang, R. T.

    2013-07-01

    The mixed-oxide (MOX) fuel decay heat behavior is analyzed for Boiling Water Reactor (BWR) Loss of Coolant Accident (LOCA) safety evaluation. The physical reasoning on why the decay heat power fractions of MOX fuel fission product (FP) are significantly lower than the corresponding decay heat power fractions of uranium-oxide (UOX) fuel FP is illustrated. This is primarily due to the following physical phenomena. -The recoverable energies per fission of plutonium (Pu)-239 and Pu-241 are significantly higher than those of uranium (U)-235 and U-238. Consequently, the fission rate required to produce the same amount of power in MOX fuel is significantly lower than that in UOX fuel, which leads to lower subsequent FP generation rate and associated decay heat power in MOX fuel than those in UOX fuel. - The effective FP decay energy per fission of Pu-239 is significantly lower than the corresponding effective FP decay energy per fission of U-235, e.g., Pu-239's 10.63 Mega-electron-Volt (MeV) vs. U-235's 12.81 MeV at the cooling time 0.2 second. This also leads to lower decay heat power in MOX fuel than that in UOX fuel. The FP decay heat is shown to account for more than 90% of the total decay heat immediately after shutdown. The FP decay heat results based on the American National Standard Institute (ANSI)/American Nuclear Society (ANS)-5.1-1979 standard method are shown very close to the corresponding FP decay heat results based on the ANSI/ANS-5.1-2005 standard method. The FP decay heat results based on the ANSI/ANS-5.1-1979 simplified method are shown very close to but mostly slightly lower than the corresponding FP decay heat results based on the ANSI/ANS-5.1-1971 method. The FP decay heat results based on the ANSI/ANS-5.1-1979 simplified method or the ANSI/ANS-5.1-1971 method are shown significantly larger than the corresponding FP decay heat results based on the ANSI/ANS-5.1-1979 standard method or the ANSI/ANS-5.1-2005 standard method. (authors)

  19. Probabilistic approach for decay heat uncertainty estimation using URANIE platform and MENDEL depletion code

    NASA Astrophysics Data System (ADS)

    Tsilanizara, A.; Gilardi, N.; Huynh, T. D.; Jouanne, C.; Lahaye, S.; Martinez, J. M.; Diop, C. M.

    2014-06-01

    The knowledge of the decay heat quantity and the associated uncertainties are important issues for the safety of nuclear facilities. Many codes are available to estimate the decay heat. ORIGEN, FISPACT, DARWIN/PEPIN2 are part of them. MENDEL is a new depletion code developed at CEA, with new software architecture, devoted to the calculation of physical quantities related to fuel cycle studies, in particular decay heat. The purpose of this paper is to present a probabilistic approach to assess decay heat uncertainty due to the decay data uncertainties from nuclear data evaluation like JEFF-3.1.1 or ENDF/B-VII.1. This probabilistic approach is based both on MENDEL code and URANIE software which is a CEA uncertainty analysis platform. As preliminary applications, single thermal fission of uranium 235, plutonium 239 and PWR UOx spent fuel cell are investigated.

  20. Decay heat measurement of fusion related materials in an ITER-like neutron field

    NASA Astrophysics Data System (ADS)

    Morimoto, Y.; Ochiai, K.; Maekawa, F.; Wada, M.; Nishitani, T.; Takeuchi, H.

    2002-12-01

    Decay heat is one of the most important factors for the safety aspect of ITER. Especially, the prediction of decay heat with an uncertainty less than 15% for the three most important materials, i.e., copper, type-316 stainless steel (SS316) and tungsten, is strongly requested by designers of ITER. To provide experimental decay heat data needed for validation of decay heat calculations for SS316 and copper, an experiment was conducted as the ITER/EDA task T-426. An ITER-like neutron field was constructed, and decay heat source distributions in thick copper and SS316 plates were measured with the whole energy absorption spectrometer. The measured decay heat distributions in the thick sample plates were compared with the predicted values by MCNP calculations. It was found that the use of an effective activation cross-section calculated by MCNP was needed to consider the self-shielding effects and, for both cases, MCNP calculations could predict the decay heat adequately.

  1. Decay heat removal from a Particle Bed Reactor Nuclear Thermal Rocket engine

    SciTech Connect

    Gustafson, E.

    1993-06-01

    Nuclear Thermal Rockets used in propulsion systems for planetary exploration will generate significant amounts of heat following normal engine shutdown due to the buildup of and decay of radioactive fission products. The amount of energy that is generated as decay heat is approximately 2-5 percent of the energy released during nominal operation. Various schemes are possible for removing this heat, including using primary coolant (hydrogen) to cool the reactor. Depending on the amount of coolant required, this may result in a large weight penalty for the mission. This paper quantifies the amount of decay heat that must be removed from the engine, shows the resulting impact on the vehicle design for particular missions, and examines possible approaches for reducing the amount of coolant required for decay heat removal. The costs and benefits of these schemes will be shown for several different missions. The missions that will be considered include both manned Mars missions and unmanned planetary exploration missions. 6 refs.

  2. Time decay rates for the equations of the compressible heat-conductive flow through porous media

    NASA Astrophysics Data System (ADS)

    Chen, Qing; Tan, Zhong; Wu, Guochun

    2015-11-01

    We consider the time decay rates of smooth solutions to the Cauchy problem for the equations of the compressible heat-conductive flow through porous media. We prove the global existence and uniqueness of the solutions by the standard energy method. Moreover, we establish the optimal decay rates of the solution as well as its higher-order spatial derivatives. And the damping effect on the time decay rates of the solution is studied in detail.

  3. Neutronics performance and decay heat calculation of a solid target for a spallation neutron source

    NASA Astrophysics Data System (ADS)

    Nio, D.; Ooi, M.; Takenaka, N.; Furusaka, M.; Kawai, M.; Mishima, K.; Kiyanagi, Y.

    2005-08-01

    A solid target is expected to give higher neutron intensity than a liquid target of mercury at a spallation neutron source with a power of around 1 MW. We have studied the neutronic performance of a target-moderator-reflector assembly with a tungsten solid target. It is found that the neutron intensities from moderators were higher in the solid target system than in the mercury liquid target. However, the tungsten target required cladding to prevent tungsten from the corrosion of cooling water. A tungsten target with tantalum cladding has been already developed although tantalum has high decay heat. Therefore, we estimated the decay heat of the target and found that the decay heat of 0.5 mm thick tantalum was still high. We need a thinner tantalum or new cladding materials. It was revealed that adoption of a thinner tantalum or new cladding material such as chrome nitride reduced the decay heat effectively.

  4. Fission Product Decay Heat Calculations for Neutron Fission of 232Th

    NASA Astrophysics Data System (ADS)

    Son, P. N.; Hai, N. X.

    2016-06-01

    Precise information on the decay heat from fission products following times after a fission reaction is necessary for safety designs and operations of nuclear-power reactors, fuel storage, transport flasks, and for spent fuel management and processing. In this study, the timing distributions of fission products' concentrations and their integrated decay heat as function of time following a fast neutron fission reaction of 232Th were exactly calculated by the numerical method with using the DHP code.

  5. [The influence of oil heat treatment on wood decay resistance by Fourier infrared spectrum analysis].

    PubMed

    Wang, Ya-Mei; Ma, Shu-Ling; Feng, Li-Qun

    2014-03-01

    Wood preservative treatment can improve defects of plantation wood such as easy to corrupt and moth eaten. Among them heat-treatment is not only environmental and no pollution, also can improve the corrosion resistance and dimension stability of wood. In this test Poplar and Mongolian Seoteh Pine was treated by soybean oil as heat-conducting medium, and the heat treatment wood was studied for indoor decay resistance; wood chemical components before and after treatment, the effect of heat treatment on wood decay resistance performance and main mechanism of action were analysed by Fourier infrared spectrometric. Results showed that the mass loss rate of poplar fell from 19.37% to 5% and Mongolian Seoteh Pine's fell from 8.23% to 3.15%, so oil heat treatment can effectively improve the decay resistance. Infrared spectrum analysis shows that the heat treatment made wood's hydrophilic groups such as hydroxyl groups in largely reduced, absorbing capacity decreased and the moisture of wood rotting fungi necessary was reduced; during the heat treatment wood chemical components such as cellulose, hemicellu lose were degraded, and the nutrient source of wood rotting fungi growth necessary was reduced. Wood decay fungi can grow in the wood to discredit wood is because of that wood can provide better living conditions for wood decay fungi, such as nutrients, water, oxygen, and so on. The cellulose and hemicellulose in wood is the main nutrition source of wood decay fungi. So the oil heat-treatment can reduce the cellulose, hemicellulose nutrition source of wood decay fungi so as to improve the decay resistance of wood. PMID:25208386

  6. Heat transfer in turbulent decaying swirl flow in a circular pipe

    NASA Astrophysics Data System (ADS)

    Algifri, A. H.; Bhardwaj, R. K.; Rao, Y. V. N.

    1988-08-01

    Heat transfer coefficients for air are measured along a heated pipe for decaying swirl flow, generated by radial blade cascade. The results are compared with an expression proposed for predicting the heat transfer coefficients in swirling flow. The theoretical predictions are in good agreement with the experimental data, with average and maximum deviations of 7 and 11 percent, respectively. The application of the theoretical approach to the experimental results obtained by other investigators for heat transfer in a decaying swirl flow generated by short-twisted tapes and tangential slots at inlet also give rise to encouraging agreement.

  7. MAGNETIC FIELD-DECAY-INDUCED ELECTRON CAPTURES: A STRONG HEAT SOURCE IN MAGNETAR CRUSTS

    SciTech Connect

    Cooper, Randall L.; Kaplan, David L. E-mail: dkaplan@kitp.ucsb.edu

    2010-01-10

    We propose a new heating mechanism in magnetar crusts. Magnetars' crustal magnetic fields are much stronger than their surface fields; therefore, magnetic pressure partially supports the crust against gravity. The crust loses magnetic pressure support as the field decays and must compensate by increasing the electron degeneracy pressure; the accompanying increase in the electron Fermi energy induces nonequilibrium, exothermic electron captures. The total heat released via field-decay electron captures is comparable to the total magnetic energy in the crust. Thus, field-decay electron captures are an important, if not the primary, mechanism powering magnetars' soft X-ray emission.

  8. Decay heat and anti-neutrino energy spectra in fission fragments from total absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Rykaczewski, Krzysztof

    2015-10-01

    Decay studies of over forty 238U fission products have been studied using ORNL's Modular Total Absorption Spectrometer. The results are showing increased decay heat values, by 10% to 50%, and the energy spectra of anti-neutrinos shifted towards lower energies. The latter effect is resulting in a reduced number of anti-neutrinos interacting with matter, often by tens of percent per fission product. The results for several studied nuclei will be presented and their impact on decay heat pattern in power reactors and reactor anti-neutrino physics will be discussed.

  9. Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Antineutrino Spectra and Decay Heat Calculations

    NASA Astrophysics Data System (ADS)

    Porta, A.; Zakari-Issoufou, A.-A.; Fallot, M.; Algora, A.; Tain, J. L.; Valencia, E.; Rice, S.; Bui, V. M.; Cormon, S.; Estienne, M.; Agramunt, J.; Äystö, J.; Bowry, M.; Briz, J. A.; Caballero-Folch, R.; Cano-Ott, D.; Cucouanes, A.; Elomaa, V.-V.; Eronen, T.; Estévez, E.; Farrelly, G. F.; Garcia, A. R.; Gelletly, W.; Gomez-Hornillos, M. B.; Gorlychev, V.; Hakala, J.; Jokinen, A.; Jordan, M. D.; Kankainen, A.; Karvonen, P.; Kolhinen, V. S.; Kondev, F. G.; Martinez, T.; Mendoza, E.; Molina, F.; Moore, I.; Perez-Cerdán, A. B.; Podolyák, Zs.; Penttilä, H.; Regan, P. H.; Reponen, M.; Rissanen, J.; Rubio, B.; Shiba, T.; Sonzogni, A. A.; Weber, C.

    2016-03-01

    Beta decay of fission products is at the origin of decay heat and antineutrino emission in nuclear reactors. Decay heat represents about 7% of the reactor power during operation and strongly impacts reactor safety. Reactor antineutrino detection is used in several fundamental neutrino physics experiments and it can also be used for reactor monitoring and non-proliferation purposes. 92,93Rb are two fission products of importance in reactor antineutrino spectra and decay heat, but their β-decay properties are not well known. New measurements of 92,93Rb β-decay properties have been performed at the IGISOL facility (Jyväskylä, Finland) using Total Absorption Spectroscopy (TAS). TAS is complementary to techniques based on Germanium detectors. It implies the use of a calorimeter to measure the total gamma intensity de-exciting each level in the daughter nucleus providing a direct measurement of the beta feeding. In these proceedings we present preliminary results for 93Rb, our measured beta feedings for 92Rb and we show the impact of these results on reactor antineutrino spectra and decay heat calculations.

  10. Passive decay heat removal system for water-cooled nuclear reactors

    DOEpatents

    Forsberg, Charles W.

    1991-01-01

    A passive decay-heat removal system for a water-cooled nuclear reactor employs a closed heat transfer loop having heat-exchanging coils inside an open-topped, insulated box located inside the reactor vessel, below its normal water level, in communication with a condenser located outside of containment and exposed to the atmosphere. The heat transfer loop is located such that the evaporator is in a position where, when the water level drops in the reactor, it will become exposed to steam. Vapor produced in the evaporator passes upward to the condenser above the normal water level. In operation, condensation in the condenser removes heat from the system, and the condensed liquid is returned to the evaporator. The system is disposed such that during normal reactor operations where the water level is at its usual position, very little heat will be removed from the system, but during emergency, low water level conditions, substantial amounts of decay heat will be removed.

  11. Decay-phase cooling and inferred heating of M- and X-class solar flares

    SciTech Connect

    Ryan, Daniel F.; Gallagher, Peter T.; Chamberlin, Phillip C.; Milligan, Ryan O.

    2013-11-20

    In this paper, the cooling of 72 M- and X-class flares is examined using GOES/XRS and SDO/EVE. The observed cooling rates are quantified and the observed total cooling times are compared with the predictions of an analytical zero-dimensional hydrodynamic model. We find that the model does not fit the observations well, but does provide a well-defined lower limit on a flare's total cooling time. The discrepancy between observations and the model is then assumed to be primarily due to heating during the decay phase. The decay-phase heating necessary to account for the discrepancy is quantified and found be ∼50% of the total thermally radiated energy, as calculated with GOES. This decay-phase heating is found to scale with the observed peak thermal energy. It is predicted that approximating the total thermal energy from the peak is minimally affected by the decay-phase heating in small flares. However, in the most energetic flares the decay-phase heating inferred from the model can be several times greater than the peak thermal energy.

  12. Decay heat calculations for a 500 kW W-Ta spallation target

    NASA Astrophysics Data System (ADS)

    Yu, Quanzhi; Lu, Youlian; Hu, Zhiliang; Zhou, Bin; Yin, Wen; Liang, Tianjiao

    2015-05-01

    The China Spallation Neutron Source (CSNS) is a short-pulsed neutron scattering facility. The beam power is designed to be 100 kW in Phase I, with the capability of upgrading to 500 kW. Tantalum (Ta)-cladded tungsten (W) was chosen as the spallation target due to its high neutron yield. Ta claddings can solve the problem of the corrosiveness of W plates, although they produce high decay heat after intense irradiation. This paper presents the decay heat distributions and evolutions for the future upgraded 500 kW W-Ta spallation target. The calculations are performed using the MCNPX2.5 Monte Carlo code and the CINDER'90 activation code. The decay heat distributions show that for the W plates, decay heat is mainly produced via the spallation reaction process, whereas for the Ta claddings, it is mainly produced via the neutron capture process. An effective method of reducing the decay heat in the W-Ta target is also presented and discussed.

  13. Method for utilizing decay heat from radioactive nuclear wastes

    DOEpatents

    Busey, H.M.

    1974-10-14

    Management of radioactive heat-producing waste material while safely utilizing the heat thereof is accomplished by encapsulating the wastes after a cooling period, transporting the capsules to a facility including a plurality of vertically disposed storage tubes, lowering the capsules as they arrive at the facility into the storage tubes, cooling the storage tubes by circulating a gas thereover, employing the so heated gas to obtain an economically beneficial result, and continually adding waste capsules to the facility as they arrive thereat over a substantial period of time.

  14. The Gas-Cooled Fast Reactor: Report on Safety System Design for Decay Heat Removal

    SciTech Connect

    K. D. Weaver; T. Marshall; T. Y. C. Wei; E. E. Feldman; M. J. Driscoll; H. Ludewig

    2003-09-01

    The gas-cooled fast reactor (GFR) was chosen as one of the Generation IV nuclear reactor systems to be developed based on its excellent potential for sustainability through reduction of the volume and radiotoxicity of both its own fuel and other spent nuclear fuel, and for extending/utilizing uranium resources orders of magnitude beyond what the current open fuel cycle can realize. In addition, energy conversion at high thermal efficiency is possible with the current designs being considered, thus increasing the economic benefit of the GFR. However, research and development challenges include the ability to use passive decay heat removal systems during accident conditions, survivability of fuels and in-core materials under extreme temperatures and radiation, and economical and efficient fuel cycle processes. This report addresses/discusses the decay heat removal options available to the GFR, and the current solutions. While it is possible to design a GFR with complete passive safety (i.e., reliance solely on conductive and radiative heat transfer for decay heat removal), it has been shown that the low power density results in unacceptable fuel cycle costs for the GFR. However, increasing power density results in higher decay heat rates, and the attendant temperature increase in the fuel and core. Use of active movers, or blowers/fans, is possible during accident conditions, which only requires 3% of nominal flow to remove the decay heat. Unfortunately, this requires reliance on active systems. In order to incorporate passive systems, innovative designs have been studied, and a mix of passive and active systems appears to meet the requirements for decay heat removal during accident conditions.

  15. Natural circulation decay heat removal from an SP-100, 550 kWe power system for a lunar outpost

    NASA Technical Reports Server (NTRS)

    El-Genk, Mohamed S.; Xue, Huimin

    1992-01-01

    This research investigated the decay heat removal from the SP-100 reactor core of a 550-kWe power system for a lunar outpost by natural circulation of lithium coolant. A transient model that simulates the decay heat removal loop (DHRL) of the power system was developed and used to assess the system's decay heat removal capability. The effects of the surface area of the decay heat rejection radiator, the dimensions of the decay heat exchanger (DHE) flow duct, the elevation of the DHE, and the diameter of the rise and down pipes in the DHRL on the decay heat removal capability were examined. Also, to determine the applicability of test results at earth gravity to actual system performance on the lunar surface, the effect of the gravity constant (1 g and 1/6 g) on the thermal behavior of the system after shutdown was investigated.

  16. A Review on the Finite Element Methods for Heat Conduction in Functionally Graded Materials

    NASA Astrophysics Data System (ADS)

    Sharma, R.; Jadon, V. K.; Singh, B.

    2015-01-01

    The review presented in this paper focuses mainly on the application of finite element methods for investigating the effect of heat transfer, variation of temperature and other parameters in the functionally graded materials. Different methods have been investigated for thermal conduction in functionally graded materials. The use of FEM for steady state heat transfer has been addressed in this work. The authors have also discussed the utilization of FEM based shear deformation theories and FEM in combination with other methods for the problems involving complexity of the shape and geometry of functionally graded materials. Finite element methods proved to be effective for the solution of heat transfer problem in functionally graded materials. These methods can be used for steady state heat transfer and as well as for transient state.

  17. Decay Heat Removal by Natural Circulation of Vacuum Vessel Coolant for ITER

    NASA Astrophysics Data System (ADS)

    Iseli, M.; Bartels, H.-W.; Poucet, A.

    1997-06-01

    The decay heat-driven temperature transients of the in-vessel components following a postulated loss of all in-vessel cooling have been calculated. The resulting time-dependent heat load to the vacuum vessel is due to radiation from the backplate and convection of postulated steam between backplate and vacuum vessel. It is shown, that even for a failure of all in-vessel cooling and total loss of power, the ITER design can rely on passive decay heat removal by natural circulation in one of the two existing cooling loops of the vacuum vessel. A mathematical model describes the transient operating conditions and shows that the temperature established by natural circulation does not exceed 200°C at the maximum shut down heat load to the vacuum vessel. Therefore, no additional emergency cooling system is required if the existing heat exchanger is designed for natural circulation and a bypass is used during normal operation to maintain operation temperature.

  18. A PRA case study of extended long term decay heat removal for shutdown risk assessment

    SciTech Connect

    Roglans, J.; Ragland, W.A.; Hill, D.J.

    1992-12-01

    A Probabilistic Risk Assessment (PRA) of the Experimental Breeder Reactor II (EBR-II), a Department of Energy (DOE) Category A research reactor, has recently been completed at Argonne National Laboratory (ANL). The results of this PRA have shown that the decay heat removal system for EBR-II is extremely robust and reliable. In addition, the methodology used demonstrates how the actions of other systems not normally used for actions of other systems not normally used for decay heat removal can be used to expand the mission time of the decay heat removal system and further increase its reliability. The methodology may also be extended to account for the impact of non-safety systems in enhancing the reliability of other dedicated safety systems.

  19. A PRA case study of extended long term decay heat removal for shutdown risk assessment

    SciTech Connect

    Roglans, J.; Ragland, W.A.; Hill, D.J.

    1992-01-01

    A Probabilistic Risk Assessment (PRA) of the Experimental Breeder Reactor II (EBR-II), a Department of Energy (DOE) Category A research reactor, has recently been completed at Argonne National Laboratory (ANL). The results of this PRA have shown that the decay heat removal system for EBR-II is extremely robust and reliable. In addition, the methodology used demonstrates how the actions of other systems not normally used for actions of other systems not normally used for decay heat removal can be used to expand the mission time of the decay heat removal system and further increase its reliability. The methodology may also be extended to account for the impact of non-safety systems in enhancing the reliability of other dedicated safety systems.

  20. Transient testing of the FFTF for decay-heat removal by natural convection

    SciTech Connect

    Beaver, T R; Johnson, H G; Stover, R L

    1982-06-01

    This paper reports on the series of transient tests performed in the FFTF as a major part of the pre-operations testing program. The structure of the transient test program was designed to verify the capability of the FFTF to safely remove decay heat by natural convection. The series culminated in a scram from full power to complete natural convection in the plant, simulating a loss of all electrical power. Test results and acceptance criteria related to the verification of safe decay heat removal are presented.

  1. Emergency Decay Heat Removal in a GEN-IV Gas-Cooled Fast Reactor

    SciTech Connect

    Cheng, Lap Y.; Ludewig, Hans; Jo, Jae

    2006-07-01

    A series of transient analyses using the system code RELAP5-3d has been performed to confirm the efficacy of a proposed hybrid active/passive combination approach to the decay heat removal for an advanced 2400 MWt GEN-IV gas-cooled fast reactor. The accident sequence of interest is a station blackout simultaneous with a small break (10 sq.inch/0.645 m{sup 2}) in the reactor vessel. The analyses cover the three phases of decay heat removal in a depressurization accident: (1) forced flow cooling by the power conversion unit (PCU) coast down, (2) active forced flow cooling by a battery powered blower, and (3) passive cooling by natural circulation. The blower is part of an emergency cooling system (ECS) that by design is to sustain passive decay heat removal via natural circulation cooling 24 hours after shutdown. The RELAP5 model includes the helium-cooled reactor, the ECS (primary and secondary side), the PCU with all the rotating machinery (turbine and compressors) and the heat transfer components (recuperator, pre-cooler and inter-cooler), and the guard containment that surrounds the reactor and the PCU. The transient analysis has demonstrated the effectiveness of passive decay heat removal by natural circulation cooling when the guard containment pressure is maintained at or above 800 kPa. (authors)

  2. A simple method for prediction of first-order modal field and cladding decay parameter in graded index fiber

    NASA Astrophysics Data System (ADS)

    Patra, P.; Gangopadhyay, S.; Goswami, K.

    2008-04-01

    Based on a series expansion method involving the Chebyshev technique, we present analytical expressions for first higher order modal field as well as cladding decay parameter in case of graded index fiber. This method utilizes the formulation of a linear relation of the ratio of first- and zero-order modified Bessel functions, with reciprocal of Cladding decay parameterE This leads to the evaluation of the Cladding decay parameter from a simple equation involving a third-order determinant and the first higher order modal field is thereafter found from two simple equations. Thus the paper presents the technique of avoiding complicated calculations of Chebyshev coefficients and therefore, the present formalism will be extremely important for practical engineering problems. Taking step and parabolic index fibers as examples, we show that our estimations of the said propagation characteristics agree excellently with the available exact results. The concerned calculations involve very little computations.

  3. Analysis of MERCI decay heat measurement for PWR UO{sub 2} fuel rod

    SciTech Connect

    Jaboulay, J.C.; Bourganel, S.

    2012-01-15

    Decay heat measurements, called the MERCI experiment, were conducted at Commissariat a l'Energie Atomique (CEA)/Saclay to characterize accurately residual power at short cooling time and verify its prediction by decay code and nuclear data. The MOSAIC calorimeter, developed and patented by CEA/Grenoble (DTN/SE2T), enables measurement of the decay heat released by a pressurized water reactor (PWR) fuel rod sample between 200 and 4 W within a precision of 1%. The MERCI experiment included three phases. At first, a UO{sub 2} fuel rod sample was irradiated in the CEA/Saclay experimental reactor OSIRIS. The burnup achieved at the end of irradiation was similar to 3.5 GWd/tonne. The second phase was the transfer of the fuel rod sample from its irradiation location to a hot cell, to be inserted inside the MOSAIC calorimeter. It took 26 min to carry out the transfer. Finally, decay heat released by the PWR sample was measured from 27 min to 42 days after shutdown. Post irradiation examinations were performed to measure concentrations of some heavy nuclei (U, Pu) and fission products (Cs, Nd). The decay heat was predicted using a calculation scheme based on the PEPIN2 depletion code, the TRIPOLI-4 Monte Carlo code, and the JEFF3.1.1 nuclear data file. The MERCI experiment analysis shows that the discrepancy between the calculated and the experimental decay heat values is included between -10% at 27 min and +6% at 12 h, 30 min otter shutdown. From 4 up to 42 days of cooling time, the difference between calculation and measurement is about ± 1%, i.e., experimental uncertainty. The MERCI experiment represents a significant contribution for code validation; the time range above 10{sup 5} s has not been validated previously. (authors)

  4. A Modular Radiant-Heat-Initiated Passive Decay-Heat-Removal System for Salt-Cooled Reactors

    SciTech Connect

    Forsberg, Charles W

    2007-01-01

    The Advanced High-Temperature Reactor (AHTR), also called the liquid-salt-cooled very high temperature reactor, is a new reactor concept that combines four existing technologies to create a new reactor option: coated-particle graphite-matrix fuels (the same fuel as used in high-temperature gas-cooled reactors), a liquid-fluoride-salt coolant with a boiling point >1200 C, Brayton power cycles, and passive safety systems. A new passive decay-heat cooling system has been invented that is actuated by the increased temperature of the salt under accident conditions and uses radiant heat transfer from and through the salt to a heat exchanger. This safety system takes advantage of two physical properties of the system: (1) the transparency of the salt coolant and (2) the increase in the radiant heat transfer from the salt to a decay-heat exchanger, which is proportional to the temperature of the hot salt to the fourth power (T4) minus the temperature of the heat exchanger surface to the fourth power (T4). For a high-temperature reactor, small increases in coolant temperatures dramatically increase radiant heat transfer.

  5. An investigation of natural circulation decay heat removal from an SP-100 reactor system for a lunar outpost

    NASA Astrophysics Data System (ADS)

    El-Genk, Mohamed S.; Xue, Huimin

    1992-01-01

    A transient thermal-hydraulic model of the decay heat removal from a 550 kWe SP-100 power system for a lunar outpost has been developed and used to assess the coolability of the system by natural circulation after reactor shutdown. Results show that natural circulation of lithium coolant is sufficient to ensure coolability of the reactor core after shutdown. Further improvement of the decay heat removal capability of the system could be achieved by increasing the dimensions of the decay heat exchanger duct. A radiator area of 10-15 m2 would be sufficient to maintain the reactor core safely coolable by natural circulation after shutdown. Increasing the area of the decay heat rejection radiator or the diameter of the heat pipes in the guard vessel wall insignificantly affects the decay heat removal capability of the system.

  6. Evaluation of spent fuel isotopics, radiation spectra and decay heat using the scale computational system

    SciTech Connect

    Parks, C.V.; Hermann, O.W.; Ryman, J.C.

    1986-01-01

    In order to be a self-sufficient system for transport/storage cask shielding and heat transfer analysis, the SCALE system developers included modules to evaluate spent fuel radiation spectra and decay heat. The primary module developed for these analyses is ORIGEN-S which is an updated verision of the original ORIGEN code. The COUPLE module was also developed to enable ORIGEN-S to easily utilize multigroup cross sections and neutron flux data during a depletion analysis. Finally, the SAS2 control module was developed for automating the depletion and decay via ORIGEN-S while using burnup-dependent neutronic data based on a user-specified fuel assembly and reactor history. The ORIGEN-S data libraries available for depletion and decay have also been significantly updated from that developed with the original ORIGEN code.

  7. Calculation of DWPF Canister Decay Heat for Sludge Macro-Batches 1B to 9

    SciTech Connect

    Choi, A. S.

    1999-04-27

    The rates of heat generation of DWPF glass canisters due to radioactive decay have been estimated for the remaining nine macro-batches of sludge feed. The estimated decay heat ranged from 177.5 Watts for each Macro-batch 1B canister to 498.4 Watts for each Macro-batch 8 canister. These projections are based on the HLW radionuclide inventory data available as of 4/1/98, and do not reflect further decay since then. It was assumed that each DWPF glass canister would also contain a nominal quantity of salt waste based on the reference coupled feed flowsheet. Issue of this report successfully closes a recent technical assistance request (HLW/DWPF-TAR-990003).

  8. Collection of low-grade waste heat for enhanced energy harvesting

    NASA Astrophysics Data System (ADS)

    Dede, Ercan M.; Schmalenberg, Paul; Wang, Chi-Ming; Zhou, Feng; Nomura, Tsuyoshi

    2016-05-01

    Enhanced energy harvesting through the collection of low-grade waste heat is experimentally demonstrated. A structural optimization technique is exploited in the design of a thermal-composite substrate to guide and gather the heat emanating from multiple sources to a predetermined location. A thermoelectric generator is then applied at the selected focusing region to convert the resulting low-grade waste heat to electrical power. The thermal characteristics of the device are experimentally verified by direct temperature measurements of the system and numerically validated via heat conduction simulations. Electrical performance under natural and forced convection is measured, and in both cases, the device with optimized heat flow control plus energy harvesting demonstrates increased power generation when compared with a baseline waste heat recovery system. Electronics applications include energy scavenging for autonomously powered sensor networks or self-actuated devices.

  9. Observation of the parametric decay instability during electron cyclotron resonance heating on the Versator 2 Tokamak

    NASA Astrophysics Data System (ADS)

    McDermott, F. S.; Bekefi, G.; Porkolab, M.

    1982-03-01

    A nonlinear, three wave interaction process occurring during high power electron cyclotron heating in the Versator II Tokamak were observed. The measured spectra and the threshold power are consistent with a model in which the incident power in the extraordinary mode of polarization decays at the upper hybrid resonance layer into a lower hybrid wave and an electron Bernstein wave.

  10. Thermal Capacitance (Slug) Calorimeter Theory Including Heat Losses and Other Decaying Processes

    NASA Technical Reports Server (NTRS)

    Hightower, T. Mark; Olivares, Ricardo A.; Philippidis, Daniel

    2008-01-01

    A mathematical model, termed the Slug Loss Model, has been developed for describing thermal capacitance (slug) calorimeter behavior when heat losses and other decaying processes are not negligible. This model results in the temperature time slope taking the mathematical form of exponential decay. When data is found to fit well to this model, it allows a heat flux value to be calculated that corrects for the losses and may be a better estimate of the cold wall fully catalytic heat flux, as is desired in arc jet testing. The model was applied to the data from a copper slug calorimeter inserted during a particularly severe high heating rate arc jet run to illustrate its use. The Slug Loss Model gave a cold wall heat flux 15% higher than the value of 2,250 W/sq cm obtained from the conventional approach to processing the data (where no correction is made for losses). For comparison, a Finite Element Analysis (FEA) model was created and applied to the same data, where conduction heat losses from the slug were simulated. The heat flux determined by the FEA model was found to be in close agreement with the heat flux determined by the Slug Loss Model.

  11. Thermoelectric energy converter for generation of electricity from low-grade heat

    DOEpatents

    Jayadev, T.S.; Benson, D.K.

    1980-05-27

    A thermoelectric energy conversion device which includes a plurality of thermoelectric elements is described. A hot liquid is supplied to one side of each element and a cold liquid is supplied to the other side of each element. The thermoelectric generator may be utilized to produce power from low-grade heat sources such as ocean thermal gradients, solar ponds, and low-grade geothermal resources. (WHK)

  12. Decay Heat Calculations for PWR and BWR Assemblies Fueled with Uranium and Plutonium Mixed Oxide Fuel using SCALE

    SciTech Connect

    Ade, Brian J; Gauld, Ian C

    2011-10-01

    in MOX fuel is generally obtained from reprocessed irradiated nuclear fuel, whereas weapons-grade plutonium is obtained from decommissioned nuclear weapons material and thus has a different plutonium (and other actinides) concentration. Using MOX fuel instead of UOX fuel has potential impacts on the neutronic performance of the nuclear fuel and the design of the nuclear fuel must take these differences into account. Each of the plutonium sources (RG and WG) has different implications on the neutronic behavior of the fuel because each contains a different blend of plutonium nuclides. The amount of heat and the number of neutrons produced from fission of plutonium nuclides is different from fission of {sup 235}U. These differences in UOX and MOX do not end at discharge of the fuel from the reactor core - the short- and long-term storage of MOX fuel may have different requirements than UOX fuel because of the different discharged fuel decay heat characteristics. The research documented in this report compares MOX and UOX fuel during storage and disposal of the fuel by comparing decay heat rates for typical pressurized water reactor (PWR) and boiling water reactor (BWR) fuel assemblies with and without weapons-grade (WG) and reactor-grade (RG) MOX fuel.

  13. Performance of Decay Heat Removal Systems in the LS-VHTR

    SciTech Connect

    Sienicki, James J.; Moisseytsev, Anton; Farmer, Mitchell T.; Dunn, Floyd E.; Cahalan, James E.

    2006-07-01

    Investigations are underway to determine the viability of the Liquid Salt-Cooled - Very High Temperature Reactor (LS-VHTR) concept which combines fuel and moderator similar to gas cooled VHTR concepts but utilizes liquid salt coolant which can operate at low pressures with improved heat transfer properties relative to helium. Analyses have been carried out investigating the viability of two alternative passive approaches for emergency decay heat removal for a 2400 MWt LS-VHTR: RVACS air natural circulation cooling of the exterior of the guard vessel and DRACS Direct Reactor Heat Exchangers (DRHXs) immersed in the liquid salt coolant and connected to natural draft air heat exchangers through secondary and tertiary cooling circuits. Results of first principles and integrated systems analyses of RVACS and DRACS performance are presented for a postulated accident scenario involving loss-of-normal heat removal, loss-of-forced (pumped) liquid salt flow, and successful scram of the reactor. (authors)

  14. Radiotoxicity and decay heat power of spent nuclear fuel of VVER type reactors at long-term storage.

    PubMed

    Bergelson, B R; Gerasimov, A S; Tikhomirov, G V

    2005-01-01

    Radiotoxicity and decay heat power of the spent nuclear fuel of VVER-1000 type reactors are calculated during storage time up to 300,000 y. Decay heat power of radioactive waste (radwaste) determines parameters of the heat removal system for the safe storage of spent nuclear fuel. Radiotoxicity determines the radiological hazard of radwaste after its leakage and penetration into the environment. PMID:16381764

  15. Studies of the Deteriorated Turbulent Heat Transfer Regime for the Gas-Cooled Fast Reactor Decay Heat Removal System

    SciTech Connect

    Jeong Ik Lee; Hejzlar, Pavel; Kazimi, Mujid S.; Saha, Pradip

    2006-07-01

    Increased reliance on passive emergency cooling using natural circulation of gas at elevated pressure is one of the major goals for the Gas-cooled Fast Reactor (GFR). Since GFR cores have high power density and low thermal inertia, the decay heat removal (DHR) in depressurization accidents is a key challenge. Furthermore, due to its high surface heat flux and low velocities under natural circulation in any post-LOCA scenario, three effects impair the capability of turbulent gas flow to remove heat from the GFR core, namely: (1) Acceleration effect (2) Buoyancy effect (3) Properties variation. This paper reviews previous work on heat transfer mechanisms and flow characteristics of the Deteriorated Turbulent Heat Transfer (DTHT) regime. It is shown that the GFR's DHR system has a potential for operating in the DTHT regime by performing a simple analysis. A description of the MIT/INL experimental facility designed and built to investigate the DTHT regime is provided together with the first test results. The first runs were performed in the forced convection regime to verify facility operation against well-established forced convection correlations. The results of the three runs at Reynolds numbers 6700, 8000 and 12800 showed good agreement with the Gnielinsky correlation [4], which is considered the best available heat transfer correlation in the forced convection regime and is valid for a large range of Reynolds and Prandtl numbers. However, even in the forced convection regime, the effect of heat transfer properties variation of the fluid was found to be still significant. (authors)

  16. Self-Driven Decay Heat Removal in a GCR Closed Brayton Cycle Power System

    SciTech Connect

    Wright, Steven A.; Lipinski, Ronald J.

    2006-07-01

    Closed Brayton Cycle (CBC) systems that are driven by Gas Cooled Reactors (GCR) are being evaluated for high-efficiency electricity generation. These systems were also selected by the Naval Reactor Prime Contractor team for use as space power systems. This paper describes the decay heat removal performance of these systems. A key question for such space or terrestrial based CBC systems is how to shut down the reactor while still removing the decay heat without using substantial amounts of auxiliary power. Tests in the Sandia Brayton Loop (SBL) show that the Brayton cycle is capable of operating on sensible heat for very long times ({approx} hour) after the reactor is shut down. This paper describes the measured and predicted results of generated electrical power produced as a function of time after the heat source had been turned off in the Sandia Brayton Loop. The measured results were obtained from an electrically heated closed Brayton cycle test loop (SBL) that Sandia fabricated and has operating within the laboratories. The predicted behavior is based on integrated dynamic system models that are capable of predicting both the transient and steady state behavior of nuclear heated or electrically heated Brayton cycle systems. The measured data was obtained by running the SBL and shutting off the electrical heater while adjusting the flow through the loop to keep the system operating at (or just above) its self-sustaining operating power level. During the test we were able to produce {approx}500 W of power for over 73 minutes after the heater power was turned off. Thus the Brayton loop was able to operate at self-sustaining conditions (or better) for over one hour. During this time the turbo-compressor was transporting the sensible heat in the heater, ducting, and recuperator to the waste heat rejection system for over an hour. For a reactor-driven system in space, this would give the shutdown decay power sufficient time to decay to levels where it could be

  17. Study of Nuclear Decay Data Contribution to Uncertainties in Heat Load Estimations for Spent Fuel Pools

    NASA Astrophysics Data System (ADS)

    Ferroukhi, H.; Leray, O.; Hursin, M.; Vasiliev, A.; Perret, G.; Pautz, A.

    2014-04-01

    At the Paul Scherrer Institut (PSI), a methodology for nuclear data uncertainty propagation in CASMO-5M (C5M) assembly calculations is under development. This paper presents a preliminary application of this methodology to C5M decay heat calculations. Applying a stochastic sampling method, nuclear decay data uncertainties are first propagated for the cooling phase only. Thereafter, the uncertainty propagation is enlarged to gradually account for cross-section as well as fission yield uncertainties during the depletion phase. On that basis, assembly heat load uncertainties as well as total uncertainty for the entire pool are quantified for cooling times up to one year. The relative contributions from the various types of nuclear data uncertainties are in this context also estimated.

  18. PLASMA HEATING IN THE VERY EARLY AND DECAY PHASES OF SOLAR FLARES

    SciTech Connect

    Falewicz, R.; Rudawy, P.; Siarkowski, M. E-mail: rudawy@astro.uni.wroc.pl

    2011-05-20

    In this paper, we analyze the energy budgets of two single-loop solar flares under the assumption that non-thermal electrons (NTEs) are the only source of plasma heating during all phases of both events. The flares were observed by RHESSI and GOES on 2002 September 20 and 2002 March 17, respectively. For both investigated flares we derived the energy fluxes contained in NTE beams from the RHESSI observational data constrained by observed GOES light curves. We showed that energy delivered by NTEs was fully sufficient to fulfill the energy budgets of the plasma during the pre-heating and impulsive phases of both flares as well as during the decay phase of one of them. We concluded that in the case of the investigated flares there was no need to use any additional ad hoc heating mechanisms other than heating by NTEs.

  19. Testing JEFF-3.1.1 and ENDF/B-VII.1 Decay and Fission Yield Nuclear Data Libraries with Fission Pulse Neutron Emission and Decay Heat Experiments

    NASA Astrophysics Data System (ADS)

    Cabellos, O.; de Fusco, V.; Diez de la Obra, C. J.; Martinez, J. S.; Gonzalez, E.; Cano-Ott, D.; Alvarez-Velarde, F.

    2014-04-01

    The aim of this work is to test the present status of Evaluated Nuclear Decay and Fission Yield Data Libraries to predict decay heat and delayed neutron emission rate, average neutron energy and neutron delayed spectra after a neutron fission pulse. Calculations are performed with JEFF-3.1.1 and ENDF/B-VII.1, and these are compared with experimental values. An uncertainty propagation assessment of the current nuclear data uncertainties is performed.

  20. Heat recovery and pollutant cleanup from low grade fuels

    SciTech Connect

    Ellison, W.; Butcher, T.A.; Carbonara, J.C.; Heaphy, J.P.

    1994-06-01

    Technical development efforts and field testing have pointed to outstanding economy and environmental benefits contemplated in revamping of fueling for reduced cost of power generation. Flue gas cleaning technologies detailed herein are expected to vitally support this objective and strongly contribute to long-term efforts for regional ozone compliance within the favorable economic framework made possible by avoidance of clean, high-cost, steam boiler fuels otherwise necessary in meeting environmental goals. With adequate control of emissions, abundance and attractive price of high-sulfur residium or coal provides the realistic basis for cost-effective power generation in decades ahead. A key element is the design of by-product yielding, wet flue gas desulfurization processes. The choice is among those using lime, ammonia, or sodium alkali reagents, or limestone in highly oxygen-inhibited process operation, with SO{sub 2} removal efficiency of 98+% as a result of dissolved sulfite alkalinity. Integrated use of condensing heat exchangers provides low-level heat recovery and water-condensing-mode scrubbing. SO{sub 3} gas & PM-10 particulates including trace metals are effectively removed in conjunction with optimal, ultra-efficient, simultaneous multi-pollutant reduction. DeNO{sub x} may be accomplished by combining advantageous recirculation of highly-cooled, low-humidity, clean flue gas to burner windboxes with conventional selective non-catalytic reduction. Stack NO{sub x} at 18 to 30 ppM, (60% O{sub 2} basis), i.e. 0.03 to 0.05 lb NO{sub 2}-equivalent/MM Btu, may be achieved by injection of methanol in dilute solution or highly air-diluted, into the rear boiler cavity upstream of the economizer, converting flue-gas NO to NO{sub 2}, thereafter efficiently absorbed and chemically reduced to N{sub 2} by the dissolved-sulfite scrubbing agent to gain colorless discharge with NO{sub 2} concentration less than 15 ppM, i.e. 0.025 lb/MM Btu.

  1. Variation of Mechanical Properties of High RRR And Reactor Grade Niobium With Heat Treatments

    SciTech Connect

    Ganapati Myneni; H. Umezawa

    2003-06-01

    Superconducting rf cavities used as accelerating structures in particle accelerators are made from high purity niobium with residual resistance ratios greater than 250. Reactor grade niobium is also used to make wave-guide and/or end group components for these accelerating structures. The major impurities in this type of niobium are interstitially dissolved gases such as hydrogen, nitrogen, and oxygen in addition to carbon. After fabricating the niobium accelerating structures, they are subjected to heat treatments for several hours in vacuum at temperatures of up to 900 C for degassing hydrogen or up to 1400 C for improving the thermal conductivity of niobium considerably. These heat treatments are affecting the mechanical properties of niobium drastically. In this paper the variation of the mechanical properties of high purity and reactor grade niobium with heat treatments in a vacuum of {approx} 10{sup -6} Torr and temperatures from 600 C to 1250 C for periods of 10 to 6 hours are presented.

  2. Heat-induced ribosome pausing triggers mRNA co-translational decay in Arabidopsis thaliana.

    PubMed

    Merret, Rémy; Nagarajan, Vinay K; Carpentier, Marie-Christine; Park, Sunhee; Favory, Jean-Jacques; Descombin, Julie; Picart, Claire; Charng, Yee-Yung; Green, Pamela J; Deragon, Jean-Marc; Bousquet-Antonelli, Cécile

    2015-04-30

    The reprogramming of gene expression in heat stress is a key determinant to organism survival. Gene expression is downregulated through translation initiation inhibition and release of free mRNPs that are rapidly degraded or stored. In mammals, heat also triggers 5'-ribosome pausing preferentially on transcripts coding for HSC/HSP70 chaperone targets, but the impact of such phenomenon on mRNA fate remains unknown. Here, we provide evidence that, in Arabidopsis thaliana, heat provokes 5'-ribosome pausing leading to the XRN4-mediated 5'-directed decay of translating mRNAs. We also show that hindering HSC/HSP70 activity at 20°C recapitulates heat effects by inducing ribosome pausing and co-translational mRNA turnover. Strikingly, co-translational decay targets encode proteins with high HSC/HSP70 binding scores and hydrophobic N-termini, two characteristics that were previously observed for transcripts most prone to pausing in animals. This work suggests for the first time that stress-induced variation of translation elongation rate is an evolutionarily conserved process leading to the polysomal degradation of thousands of 'non-aberrant' mRNAs. PMID:25845591

  3. Hybrid finite volume/ finite element method for radiative heat transfer in graded index media

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Zhao, J. M.; Liu, L. H.; Wang, S. Y.

    2012-09-01

    The rays propagate along curved path determined by the Fermat principle in the graded index medium. The radiative transfer equation in graded index medium (GRTE) contains two specific redistribution terms (with partial derivatives to the angular coordinates) accounting for the effect of the curved ray path. In this paper, the hybrid finite volume with finite element method (hybrid FVM/FEM) (P.J. Coelho, J. Quant. Spectrosc. Radiat. Transf., vol. 93, pp. 89-101, 2005) is extended to solve the radiative heat transfer in two-dimensional absorbing-emitting-scattering graded index media, in which the spatial discretization is carried out using a FVM, while the angular discretization is by a FEM. The FEM angular discretization is demonstrated to be preferable in dealing with the redistribution terms in the GRTE. Two stiff matrix assembly schemes of the angular FEM discretization, namely, the traditional assembly approach and a new spherical assembly approach (assembly on the unit sphere of the solid angular space), are discussed. The spherical assembly scheme is demonstrated to give better results than the traditional assembly approach. The predicted heat flux distributions and temperature distributions in radiative equilibrium are determined by the proposed method and compared with the results available in other references. The proposed hybrid FVM/FEM method can predict the radiative heat transfer in absorbing-emitting-scattering graded index medium with good accuracy.

  4. Nuclear mass inventory, photon dose rate and thermal decay heat of spent research reactor fuel assemblies

    SciTech Connect

    Pond, R.B.; Matos, J.E.

    1996-12-31

    This document has been prepared to assist research reactor operators possessing spent fuel containing enriched uranium of United States origin to prepare part of the documentation necessary to ship this fuel to the United States. Data are included on the nuclear mass inventory, photon dose rate, and thermal decay heat of spent research reactor fuel assemblies. Isotopic masses of U, Np, Pu and Am that are present in spent research reactor fuel are estimated for MTR, TRIGA and DIDO-type fuel assembly types. The isotopic masses of each fuel assembly type are given as functions of U-235 burnup in the spent fuel, and of initial U-235 enrichment and U-235 mass in the fuel assembly. Photon dose rates of spent MTR, TRIGA and DIDO-type fuel assemblies are estimated for fuel assemblies with up to 80% U-235 burnup and specific power densities between 0.089 and 2.857 MW/kg[sup 235]U, and for fission product decay times of up to 20 years. Thermal decay heat loads are estimated for spent fuel based upon the fuel assembly irradiation history (average assembly power vs. elapsed time) and the spent fuel cooling time.

  5. An electrochemical system for efficiently harvesting low-grade heat energy.

    PubMed

    Lee, Seok Woo; Yang, Yuan; Lee, Hyun-Wook; Ghasemi, Hadi; Kraemer, Daniel; Chen, Gang; Cui, Yi

    2014-01-01

    Efficient and low-cost thermal energy-harvesting systems are needed to utilize the tremendous low-grade heat sources. Although thermoelectric devices are attractive, its efficiency is limited by the relatively low figure-of-merit and low-temperature differential. An alternative approach is to explore thermodynamic cycles. Thermogalvanic effect, the dependence of electrode potential on temperature, can construct such cycles. In one cycle, an electrochemical cell is charged at a temperature and then discharged at a different temperature with higher cell voltage, thereby converting heat to electricity. Here we report an electrochemical system using a copper hexacyanoferrate cathode and a Cu/Cu(2+) anode to convert heat into electricity. The electrode materials have low polarization, high charge capacity, moderate temperature coefficients and low specific heat. These features lead to a high heat-to-electricity energy conversion efficiency of 5.7% when cycled between 10 and 60 °C, opening a promising way to utilize low-grade heat. PMID:24845707

  6. An electrochemical system for efficiently harvesting low-grade heat energy

    NASA Astrophysics Data System (ADS)

    Lee, Seok Woo; Yang, Yuan; Lee, Hyun-Wook; Ghasemi, Hadi; Kraemer, Daniel; Chen, Gang; Cui, Yi

    2014-05-01

    Efficient and low-cost thermal energy-harvesting systems are needed to utilize the tremendous low-grade heat sources. Although thermoelectric devices are attractive, its efficiency is limited by the relatively low figure-of-merit and low-temperature differential. An alternative approach is to explore thermodynamic cycles. Thermogalvanic effect, the dependence of electrode potential on temperature, can construct such cycles. In one cycle, an electrochemical cell is charged at a temperature and then discharged at a different temperature with higher cell voltage, thereby converting heat to electricity. Here we report an electrochemical system using a copper hexacyanoferrate cathode and a Cu/Cu2+ anode to convert heat into electricity. The electrode materials have low polarization, high charge capacity, moderate temperature coefficients and low specific heat. These features lead to a high heat-to-electricity energy conversion efficiency of 5.7% when cycled between 10 and 60 °C, opening a promising way to utilize low-grade heat.

  7. System Analysis for Decay Heat Removal in Lead-Bismuth-Cooled Natural-Circulation Reactors

    SciTech Connect

    Sakai, Takaaki; Enuma, Yasuhiro; Iwasaki, Takashi

    2004-03-15

    Decay heat removal analyses for lead-bismuth-cooled natural-circulation reactors are described in this paper. A combined multidimensional plant dynamics code (MSG-COPD) has been developed to conduct the system analysis for the natural-circulation reactors. For the preliminary study, transient analysis has been performed for a 300-MW(thermal) lead-bismuth-cooled reactor designed by Argonne National Laboratory. In addition, decay heat removal characteristics of a 400-MW(electric) lead-bismuth-cooled natural-circulation reactor designed by the Japan Nuclear Cycle Development Institute (JNC) has been evaluated by using MSG-COPD. The primary reactor auxiliary cooling system (PRACS) is prepared for the JNC concept to get sufficient heat removal capacity. During 2000 s after the transient, the outlet temperature shows increasing tendency up to the maximum temperature of 430 deg. C because the buoyancy force in a primary circulation path is temporarily reduced. However, the natural circulation is recovered by the PRACS system, and the outlet temperature decreases successfully.

  8. System Analysis for Decay Heat Removal in Lead-Bismuth Cooled Natural Circulated Reactors

    SciTech Connect

    Takaaki Sakai; Yasuhiro Enuma; Takashi Iwasaki; Kazuhiro Ohyama

    2002-07-01

    Decay heat removal analyses for lead-bismuth cooled natural circulation reactors are described in this paper. A combined multi-dimensional plant dynamics code (MSG-COPD) has been developed to conduct the system analysis for the natural circulation reactors. For the preliminary study, transient analysis has been performed for a 100 MWe lead-bismuth-cooled reactor designed by Argonne National Laboratory (ANL). In addition, decay heat removal characteristics of a 400 MWe lead-bismuth-cooled natural circulation reactor designed by Japan Nuclear Cycle Development Institute (JNC) has been evaluated by using MSG-COPD. PRACS (Primary Reactor Auxiliary Cooling System) is prepared for the JNC's concept to get sufficient heat removal capacity. During 2000 sec after the transient, the outlet temperature shows increasing tendency up to the maximum temperature of 430 Centigrade, because the buoyancy force in a primary circulation path is temporary reduced. However, the natural circulation is recovered by the PRACS system and the out let temperature decreases successfully. (authors)

  9. Membrane-Based Osmotic Heat Engine with Organic Solvent for Enhanced Power Generation from Low-Grade Heat

    SciTech Connect

    Shaulsky, E; Boo, C; Lin, SH; Elimelech, M

    2015-05-05

    We present a hybrid osmotic heat engine (OHE) system that uses draw solutions with an organic solvent for enhanced thermal separation efficiency. The hybrid OHE system produces sustainable energy by combining pressure-retarded osmosis (PRO) as a power generation stage and membrane distillation (MD) utilizing low-grade heat as a separation stage. While previous OHE systems employed aqueous electrolyte draw solutions, using methanol as a solvent is advantageous because methanol is highly volatile and has a lower heat capacity and enthalpy of vaporization than water. Hence, the thermal separation efficiency of a draw solution with methanol would be higher than that of an aqueous draw solution. In this study, we evaluated the performance of LiCl-methanol as a potential draw solution for a PRO-MD hybrid OHE system. The membrane transport properties as well as performance with LiCl methanol draw solution were evaluated using thin-film composite (TFC) PRO membranes and compared to the results obtained with a LiCl water draw solution. Experimental PRO methanol flux and maximum projected power density of 47.1 L m(-2) h(-1) and 72.1 W m(-2), respectively, were achieved with a 3 M LiCl-methanol draw solution. The overall efficiency of the hybrid OHE system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages under conditions with and without heat recovery. The modeling results demonstrate higher ORE energy efficiency with the LiCl methanol draw solution compared to that with the LiCl water draw solution under practical operating conditions (i.e., heat recovery <90%). We discuss the implications of the results for converting low-grade heat to power.

  10. Membrane-based osmotic heat engine with organic solvent for enhanced power generation from low-grade heat.

    PubMed

    Shaulsky, Evyatar; Boo, Chanhee; Lin, Shihong; Elimelech, Menachem

    2015-05-01

    We present a hybrid osmotic heat engine (OHE) system that uses draw solutions with an organic solvent for enhanced thermal separation efficiency. The hybrid OHE system produces sustainable energy by combining pressure-retarded osmosis (PRO) as a power generation stage and membrane distillation (MD) utilizing low-grade heat as a separation stage. While previous OHE systems employed aqueous electrolyte draw solutions, using methanol as a solvent is advantageous because methanol is highly volatile and has a lower heat capacity and enthalpy of vaporization than water. Hence, the thermal separation efficiency of a draw solution with methanol would be higher than that of an aqueous draw solution. In this study, we evaluated the performance of LiCl-methanol as a potential draw solution for a PRO-MD hybrid OHE system. The membrane transport properties as well as performance with LiCl-methanol draw solution were evaluated using thin-film composite (TFC) PRO membranes and compared to the results obtained with a LiCl-water draw solution. Experimental PRO methanol flux and maximum projected power density of 47.1 L m(-2) h(-1) and 72.1 W m(-2), respectively, were achieved with a 3 M LiCl-methanol draw solution. The overall efficiency of the hybrid OHE system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages under conditions with and without heat recovery. The modeling results demonstrate higher OHE energy efficiency with the LiCl-methanol draw solution compared to that with the LiCl-water draw solution under practical operating conditions (i.e., heat recovery<90%). We discuss the implications of the results for converting low-grade heat to power. PMID:25839239

  11. Passive decay heat removal by natural air convection after severe accidents

    SciTech Connect

    Erbacher, F.J.; Neitzel, H.J.; Cheng, X.

    1995-09-01

    The composite containment proposed by the Research Center Karlsruhe and the Technical University Karlsruhe is to cope with severe accidents. It pursues the goal to restrict the consequences of core meltdown accidents to the reactor plant. One essential of this new containment concept is its potential to remove the decay heat by natural air convection and thermal radiation in a passive way. To investigate the coolability of such a passive cooling system and the physical phenomena involved, experimental investigations are carried out at the PASCO test facility. Additionally, numerical calculations are performed by using different codes. A satisfying agreement between experimental data and numerical results is obtained.

  12. Fission product transport analysis in a loss of decay heat removal accident at Browns Ferry

    SciTech Connect

    Wichner, R.P.; Weber, C.F.; Hodge, S.A.; Beahm, E.C.; Wright, A.L.

    1984-01-01

    This paper summarizes an analysis of the movement of noble gases, iodine, and cesium fission products within the Mark-I containment BWR reactor system represented by Browns Ferry Unit 1 during a postulated accident sequence initiated by a loss of decay heat removal (DHR) capability following a scram. The event analysis showed that this accident could be brought under control by various means, but the sequence with no operator action ultimately leads to containment (drywell) failure followed by loss of water from the reactor vessel, core degradation due to overheating, and reactor vessel failure with attendant movement of core debris onto the drywell floor.

  13. Computer program grade 2 for the design and analysis of heat-pipe wicks

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.; Edwards, D. K.

    1976-01-01

    This user's manual describes the revised version of the computer program GRADE(1), which designs and analyzes heat pipes with graded porosity fibrous slab wicks. The revisions are: (1) automatic calculation of the minimum condenser-end stress that will not result in an excess-liquid puddle or a liquid slug in the vapor space; (2) numerical solution of the equations describing flow in the circumferential grooves to assess the burnout criterion; (3) calculation of the contribution of excess liquid in fillets and puddles to the heat-transport; (4) calculation of the effect of partial saturation on the wick performance; and (5) calculation of the effect of vapor flow, which includes viscousinertial interactions.

  14. A Model of Solar Radiation and Joule Heating in Flow of Third Grade Nanofluid

    NASA Astrophysics Data System (ADS)

    Hussain, Tariq; Hayat, Tasawar; Shehzad, Sabir Ali; Alsaedi, Ahmed; Chen, Bin

    2015-03-01

    The flow problem resulting from the stretching of a surface with convective conditions in a magnetohydrodynamic nanofluid with solar radiation is examined. Both heat and nanoparticle mass transfer convective conditions are employed. An incompressible third grade fluid which exhibits shear thinning and shear thickening characteristics is used as a base fluid. Concept of convective nanoparticle mass condition is introduced. Effects of Brownian motion and thermophoresis on magnetohydrodynamic flow of nanofluid are accounted in the presence of thermal radiation. Energy equation incorporates the features of Joule heating. The impact of physical parameters on the temperature and nanoparticle concentration has been pointed out. Numerical values of skin-friction coefficient are presented and analysed. It is hoped that this present investigation serves as a stimulus for the next generation of solar film collectors, heat exchangers technology, material processing, geothermal energy storage, and all those processes which are highly affected by the heat enhancement concept.

  15. Growth and decay of acceleration waves in non-ideal gas flow with radiative heat transfer

    NASA Astrophysics Data System (ADS)

    Singh, Lal; Singh, Raghwendra; Ram, Subedar

    2012-09-01

    The present paper is concerned with the study of the propagation of acceleration waves along the characteristic path in a non-ideal gas flow with effect of radiative heat transfer. It is shown that a linear solution in the characteristic plane can exhibit non-linear behavior in the physical plane. It is also investigated as to how the radiative heat transfer under the optically thin limit will affect the formation of shock in planer, cylindrical and spherically symmetric flows. We conclude that there exists critical amplitude such that any compressive waves with initial amplitude greater than the critical one terminate into shock waves while an initial amplitude less than the critical one results in the decay of the disturbance. The critical time for shock formation has been computed. In this paper we also compare/contrast the nature of solution in ideal and non ideal gas flows.

  16. Radionuclide mass inventory, activity, decay heat, and dose rate parametric data for TRIGA spent nuclear fuels

    SciTech Connect

    Sterbentz, J.W.

    1997-03-01

    Parametric burnup calculations are performed to estimate radionuclide isotopic mass and activity concentrations for four different Training, Research, and Isotope General Atomics (TRIGA) nuclear reactor fuel element types: (1) Aluminum-clad standard, (2) Stainless Steel-clad standard, (3) High-enrichment Fuel Life Improvement Program (FLIP), and (4) Low-enrichment Fuel Life Improvement Program (FLIP-LEU-1). Parametric activity data are tabulated for 145 important radionuclides that can be used to generate gamma-ray emission source terms or provide mass quantity estimates as a function of decay time. Fuel element decay heats and dose rates are also presented parametrically as a function of burnup and decay time. Dose rates are given at the fuel element midplane for contact, 3.0-feet, and 3.0-meter detector locations in air. The data herein are estimates based on specially derived Beginning-of-Life (BOL) neutron cross sections using geometrically-explicit TRIGA reactor core models. The calculated parametric data should represent good estimates relative to actual values, although no experimental data were available for direct comparison and validation. However, because the cross sections were not updated as a function of burnup, the actinide concentrations may deviate from the actual values at the higher burnups.

  17. Heat flux decay length during RF power operation in the Tore Supra tokamak

    NASA Astrophysics Data System (ADS)

    Corre, Y.; Gunn, J. P.; Firdaouss, M.; Carpentier, S.; Chantant, M.; Colas, L.; Ekedahl, A.; Gardarein, J.-L.; Lipa, M.; Loarer, T.; Courtois, X.; Guilhem, D.; Saint-Laurent, F.

    2014-01-01

    The upgrade of its ion cyclotron resonance (ICRH) and lower hybrid current drive (LHCD) heating systems makes the Tore Supra (TS) tokamak particularly well suited to address the physics and technology of high-power and steady-state plasma-surface interactions. High radio frequency (RF) heating powers have been successfully applied up to 12.2 MW coupled to the plasma, in which about 7.85 MW flows through the scrape-off layer. Thermal calculation based on thermography measurements gives the heat flux density distribution on the TS toroidal limiter located at the bottom of the machine. The target heat flux densities are divided by the incidence angle of the field lines with the surface and mapped to the magnetic flux surface to evaluate the power flowing in the scrape-off layer (SOL). The power profile shows a narrow component near the last closed flux surface and a wide component in the rest of the SOL. The narrow component is attributed to significant cross-field heat flux density around the plasma contact point, about 0.8% of the parallel heat flux density in the SOL, when incident angles are nearly tangential to the surface. The wide component is used to derive the experimental heat flux decay length (λq) and parallel heat flux in the SOL. The power widths are measured for a series of 1 MA/3.8 T discharges involving a scan of RF injected power 3.5 ⩽ Ptot ⩽ 12.2 MW. Independently of the heating power, we measured λq,OMP = 14.5 ± 1.5 mm at the outer mid-plane and parallel heat flux in the SOL in the range 130\\le Q_{\\parallel}^{LCFS}\\le 490\\,MW\\,m^{-2} . TS values obtained with L-mode limiter plasmas are broader than those derived from L-mode divertor plasmas, confirming earlier results obtained with an ohmically heated plasma leaning on the inboard wall of TS.

  18. Decay Heat Removal in GEN IV Gas-Cooled Fast Reactors

    DOE PAGESBeta

    Cheng, Lap-Yan; Wei, Thomas Y. C.

    2009-01-01

    The safety goal of the current designs of advanced high-temperature thermal gas-cooled reactors (HTRs) is that no core meltdown would occur in a depressurization event with a combination of concurrent safety system failures. This study focused on the analysis of passive decay heat removal (DHR) in a GEN IV direct-cycle gas-cooled fast reactor (GFR) which is based on the technology developments of the HTRs. Given the different criteria and design characteristics of the GFR, an approach different from that taken for the HTRs for passive DHR would have to be explored. Different design options based on maintaining core flow weremore » evaluated by performing transient analysis of a depressurization accident using the system code RELAP5-3D. The study also reviewed the conceptual design of autonomous systems for shutdown decay heat removal and recommends that future work in this area should be focused on the potential for Brayton cycle DHRs.« less

  19. Shutdown decay heat removal analysis: Plant case studies and special issues: Summary report

    SciTech Connect

    Ericson, D.M. Jr.; Cramond, W.R.; Sanders, G.A.; Hatch, S.W.

    1989-04-01

    Shutdown Decay Heat Removal Requirements has been designated as Unresolved Safety Issue (USI) A-45. The overall objectives of the USI A-45 program were to evaluate the safety adequacy of decay heat removal (DHR) systems in existing light water reactor nuclear power plants and to assess the value and impact (benefit-cost) of alternative measures for improving the overall reliability of the DHR function. To provide the technical data required to meet these objectives a program was developed that examined the state of DHR system reliability in a sample of existing plants. This program identified potential vulnerabilities and identified and established the feasibility of potential measures to improve the reliability of the DHR function. A value/impact (V/I) analysis of the more promising of such measures was conducted and documented. This report summarizes those studies. In addition, because of the evolving nature of V/I analyses in support of regulation, a number of supporting studies related to appropriate procedures and measures for the V/I analyses were also conducted. These studies are also summarized herein. This report only summarizes findings of technical studies performed by Sandia National Laboratories as part of the program to resolve this issue. 46 refs., 7 figs., 124 tabs.

  20. Beta dependence of electron heating in decaying whistler turbulence: Particle-in-cell simulations

    SciTech Connect

    Saito, S.; Peter Gary, S.

    2012-01-15

    Two-dimensional particle-in-cell simulations have been carried out to study electron beta dependence of decaying whistler turbulence and electron heating in a homogeneous, collisionless magnetized plasma. Initially, applied whistler fluctuations at relatively long wavelengths cascade their energy into shorter wavelengths. This cascade leads to whistler turbulence with anisotropic wavenumber spectra which are broader in directions perpendicular to the background magnetic field than in the parallel direction. Comparing the development of whistler turbulence at different electron beta values, it is found that both the wavenumber spectrum anisotropy and electron heating anisotropy decrease with increasing electron beta. This indicates that higher electron beta reduces the perpendicular energy cascade of whistler turbulence. Fluctuation energy dissipation by electron Landau damping responsible for the electron parallel heating becomes weaker at higher electron beta, which leads to more isotropic heating. It suggests that electron kinetic processes are important in determining the properties of whistler turbulence. This kinetic property is applied to discuss the generation of suprathermal strahl electron distributions in the solar wind.

  1. Study of Supercritical Carbon Dioxide Power Cycle for Low Grade Heat Conversion

    SciTech Connect

    Vidhi, Rachana; Goswami, Yogi D.; Chen, Huijuan; Stefanakos, Elias; Kuravi, Sarada; Sabau, Adrian S

    2011-01-01

    Research on supercritical carbon dioxide power cycles has been mainly focused on high temperature applications, such as Brayton cycle in a nuclear power plant. This paper conducts a comprehensive study on the feasibility of a CO2-based supercritical power cycle for low-grade heat conversion. Energy and exergy analyses of the cycle were conducted to discuss the obstacles as well as the potentials of using supercritical carbon dioxide as the working fluid for supercritical Rankine cycle, Carbon dioxide has desirable qualities such as low critical temperature, stability, little environmental impact and low cost. However, the low critical temperature might be a disadvantage for the condensation process. Comparison between a carbon dioxide-based supercritical Rankine cycle and an organic fluid-based supercritical Rankine cycle showed that the former needs higher pressure to achieve the same efficiency and a heat recovery system is necessary to desuperheat the turbine exhaust and pre-heat the pressure charged liquid.

  2. Radioactive decay products in neutron star merger ejecta: heating efficiency and γ-ray emission

    NASA Astrophysics Data System (ADS)

    Hotokezaka, K.; Wanajo, S.; Tanaka, M.; Bamba, A.; Terada, Y.; Piran, T.

    2016-06-01

    The radioactive decay of the freshly synthesized r-process nuclei ejected in compact binary mergers powers optical/infrared macronovae (kilonovae) that follow these events. The light curves depend critically on the energy partition among the different decay products and it plays an important role in estimates of the amount of ejected r-process elements from a given observed signal. We show that 20-50 per cent of the total radioactive energy is released in γ-rays on time-scales from hours to a month. The number of emitted γ-rays per unit energy interval has roughly a flat spectrum between a few dozen keV and 1 MeV so that most of the energy is carried by ˜1 MeV γ-rays. However, at the peak of macronova emission the optical depth of the γ-rays is ˜0.02 and most of the γ-rays escape. The loss of these γ-rays reduces the heat deposition into the ejecta and hence reduces the expected macronova signals if those are lanthanides dominated. This implies that the ejected mass is larger by a factor of 2-3 than what was previously estimated. Spontaneous fission heats up the ejecta and the heating rate can increase if a sufficient amount of transuranic nuclei are synthesized. Direct measurements of these escaping γ-rays may provide the ultimate proof for the macronova mechanisms and an identification of the r-process nucleosynthesis sites. However, the chances to detect these signals are slim with current X-ray and γ-ray missions. New detectors, more sensitive by at least a factor of 10, are needed for a realistic detection rate.

  3. Quantification of the decay and re-induction of heat acclimation in dry-heat following 12 and 26 days without exposure to heat stress.

    PubMed

    Weller, Andrew S; Linnane, Denise M; Jonkman, Anna G; Daanen, Hein A M

    2007-12-01

    Compared with the induction of heat acclimation (HA), studies investigating the decay and re-induction of HA (RA) are relatively sparse and have yielded conflicting results. Therefore, 16 semi-nude men were acclimated to dry-heat by undertaking an exercise protocol in a hot chamber (dry-bulb temperature 46.1 +/- 0.1 degrees C; relative humidity 17.9 +/- 0.1%) on 10 consecutive days (HA1-10) in winter UK. Thereafter, the subjects were divided into two groups and re-exposed to the work-in-heat tests after 12 and 26 days until RA was attained (RA(12), n = 8; RA(26), n = 8). The exercise protocol consisted of 60 min of treadmill walking (1.53 m s(-1)) at an incline individually set to induce a rectal temperature (T (re)) of approximately 38.5 degrees C during HA1 (equating to 45 +/- 4% peak oxygen uptake), followed by 10 min of rest and 40 min of further treadmill exercise, the intensity of which was increased across HA to maintain T(re )at approximately 38.5 degrees C. T(re), mean skin temperature, heart rate and rate of total water loss measured at 60 min did not change after HA7, and HA was taken as the mean of the responses during HA8-10. For both groups, there was no decay in T(re) and for all measured variables RA was attained after 2 and 4 days in RA(12) and RA(26), respectively. It is concluded that once adaptation to heat has been attained, the time that individuals may spend in cooler conditions before returning to a hot environment could be as long as one month, without the need for extensive re-adaptation to heat. PMID:17891541

  4. Flow and heat transfer to modified second grade fluid over a non-linear stretching sheet

    NASA Astrophysics Data System (ADS)

    Khan, Masood; Rahman, Masood ur

    2015-08-01

    The objective of the present work is to analyze the two-dimensional boundary layer flow and heat transfer of a modified second grade fluid over a non-linear stretching sheet of constant surface temperature. The modelled momentum and energy equations are deduced to a system of ordinary differential equations by employing suitable transformations in boundary layer region and integrated numerically by fourth and fifth order Runge-Kutta Fehlberg method. Additionally, the analytic solutions of the governing problem are presented for some special cases. The secured results make it clear that the power-law index reduces both the momentum and thermal boundary layers. While the incremented values of the generalized second grade parameter leads to an increase in the momentum boundary layer and a decrease in the thermal boundary layer. To see the validity of the present results we have made a comparison with the previously published results as a special case with an outstanding compatibility.

  5. Reactor Decay Heat in {sup 239}Pu: Solving the {gamma} Discrepancy in the 4-3000-s Cooling Period

    SciTech Connect

    Algora, A.; Jordan, D.; Tain, J. L.; Rubio, B.; Agramunt, J.; Perez-Cerdan, A. B.; Molina, F.; Caballero, L.; Nacher, E.; Krasznahorkay, A.; Hunyadi, M. D.; Gulyas, J.; Vitez, A.; Csatlos, M.; Csige, L.; Aeysto, J.; Penttilae, H.; Moore, I. D.; Eronen, T.; Jokinen, A.

    2010-11-12

    The {beta} feeding probability of {sup 102,104,105,106,107}Tc, {sup 105}Mo, and {sup 101}Nb nuclei, which are important contributors to the decay heat in nuclear reactors, has been measured using the total absorption technique. We have coupled for the first time a total absorption spectrometer to a Penning trap in order to obtain sources of very high isobaric purity. Our results solve a significant part of a long-standing discrepancy in the {gamma} component of the decay heat for {sup 239}Pu in the 4-3000 s range.

  6. Reactor decay heat in 239Pu: solving the γ discrepancy in the 4-3000-s cooling period.

    PubMed

    Algora, A; Jordan, D; Taín, J L; Rubio, B; Agramunt, J; Perez-Cerdan, A B; Molina, F; Caballero, L; Nácher, E; Krasznahorkay, A; Hunyadi, M D; Gulyás, J; Vitéz, A; Csatlós, M; Csige, L; Aysto, J; Penttilä, H; Moore, I D; Eronen, T; Jokinen, A; Nieminen, A; Hakala, J; Karvonen, P; Kankainen, A; Saastamoinen, A; Rissanen, J; Kessler, T; Weber, C; Ronkainen, J; Rahaman, S; Elomaa, V; Rinta-Antila, S; Hager, U; Sonoda, T; Burkard, K; Hüller, W; Batist, L; Gelletly, W; Nichols, A L; Yoshida, T; Sonzogni, A A; Peräjärvi, K

    2010-11-12

    The β feeding probability of (102,104,105,106,107)Tc, 105Mo, and 101Nb nuclei, which are important contributors to the decay heat in nuclear reactors, has been measured using the total absorption technique. We have coupled for the first time a total absorption spectrometer to a Penning trap in order to obtain sources of very high isobaric purity. Our results solve a significant part of a long-standing discrepancy in the γ component of the decay heat for 239Pu in the 4-3000 s range. PMID:21231223

  7. Modeling the decay of energy containing eddies: A source of solar wind heating

    NASA Technical Reports Server (NTRS)

    Hossain, M.; Gray, P. C.; Pontius, D. H.; Matthaeus, W. H.; Oughton, S.

    1995-01-01

    To understand the solar wind heating and acceleration mechanisms one needs to understand the decay of energy containing eddies. With this goal in mind, attempts have been made to extend the fluid dynamic phenomenology of large scale quasi-equilibrium to the case of magnetohydrodynamics. Matthaeus et al. have proposed a model for the inhomogeneous transport and decay of five mean variables, namely, two mean square Elsasser variables z(exp 2) (sub +/-) their correlation lengths, and the difference between the kinetic and magnetic energies. We test the validity of this model in the simplified case of homogeneous turbulence simulated in a periodic box. We propose a class of models and show that they may fit the simulation satisfactorily. Analytic solutions of this class of model reveal their inherent properties and demonstrate the difficulties associated with finite cross helicity. It is noted that adjustments are required to make the simplest models, which are based upon isotropic turbulence, scale properly with respect to the strength of the mean magnetic field. This can be interpreted as due to anisotropic turbulence, which can be modelled by simple parameterization in the phenomenology.

  8. BWR spent fuel storage cask performance test. Volume 2. Pre- and post-test decay heat, heat transfer, and shielding analyses

    SciTech Connect

    Wiles, L.E.; Lombardo, N.J.; Heeb, C.M.; Jenquin, U.P.; Michener, T.E.; Wheeler, C.L.; Creer, J.M.; McCann, R.A.

    1986-06-01

    This report describes the decay heat, heat transfer, and shielding analyses conducted in support of performance testing of a Ridhihalgh, Eggers and Associates REA 2033 boiling water reactor (BWR) spent fuel storage cask. The cask testing program was conducted for the US Department of Energy (DOE) Commercial Spent Fuel Management Program by the Pacific Northwest Laboratory (PNL) and by General Electric at the latters' Morris Operation (GE-MO) as reported in Volume I. The analyses effort consisted of performing pretest calculations to (1) select spent fuel for the test; (2) symmetrically load the spent fuel assemblies in the cask to ensure lateral symmetry of decay heat generation rates; (3) optimally locate temperature and dose rate instrumentation in the cask and spent fuel assemblies; and (4) evaluate the ORIGEN2 (decay heat), HYDRA and COBRA-SFS (heat transfer), and QAD and DOT (shielding) computer codes. The emphasis of this second volume is on the comparison of code predictions to experimental test data in support of the code evaluation process. Code evaluations were accomplished by comparing pretest (actually pre-look, since some predictions were not completed until testing was in progress) predictions with experimental cask testing data reported in Volume I. No attempt was made in this study to compare the two heat transfer codes because results of other evaluations have not been completed, and a comparison based on one data set may lead to erroneous conclusions.

  9. In-situ Phase transformation study in fine grained heat affected zone of Grade 91 steels

    SciTech Connect

    Babu, Sudarsanam Suresh; Yamamoto, Yukinori; Santella, Michael L; Yu, Xinghua; Komizo, Prof. Y; Terasaki, Prof. H

    2014-01-01

    Creep strength-enhanced ferritic (CSEF) steels such as the 9 Cr steel [ASTM A387 Grade 91] are widely used as tubing and piping in the new generation of fossil fired power plants. Microstructures in the fine-grained heat affected zone (FGHAZ) may significantly reduce creep strength leading Type IV failures. Current research suggest that reducing pre-weld tempering temperature from 760 C (HTT) to 650 C (LTT) has the potential to double the creep life of these welds. To understand this improvement, time-resolved X-ray diffraction (TRXRD) measurement with synchrotron radiation was used to characterize the microstructure evolution during fine grained heat-affected zone (HAZ) thermal cycling of grade 91 steel. The measurements showed both M23C6 (M=Fe, Cr) and MX (M=Nb, V; X=C,N) are present in the sample after the HTT condition. Near equilibrium fraction of M23C6 was measured in high temperature tempering condition (HTT, 760 C). However, the amount of M23C6 in LTT condition was very low since the diffraction peaks are close to the background. During simulated FGHAZ thermal cycling, the M23C6 partially dissolved in HTT sample. Interestingly, MX did not dissolve in both LTT and HTT samples. Hypothesis for correlation of M23C6 carbide distribution and pre-mature creep failure in FGHAZ will be made.

  10. The heating of nova ejecta by radioactive decays of the beta-unstable nuclei

    NASA Technical Reports Server (NTRS)

    Pistinner, Shlomi; Shaviv, Giora; Starrfield, Sumner

    1994-01-01

    Recent nucleosynthesis and hydrodynamic calculations of the consequences of accretion onto massive ONeMg white dwarf stars show that under certain circumstances significant amounts of the beta-unstable nuclei can be produced and ejected by the resulting explosion. We use these calculations as a guide in order to obtain the conditions under which the heating of the ejected material by the nonthermal electrons and positrons produced by the decays of the beta-unstable nuclei is sufficient to overcome the cooling from adiabatic expansion and lead to the production of X-ray-emitting coronal gas. These conditions are as follows: (1) a mass fraction for Na-22 of the order of 10(exp -3) or greater, (2) an expansion velocity in the range approximately 10(exp 2) - 10(exp 3) km/s, (3) a photospheric radius of approximately 10(exp 14) cm, (4) if the density distribution in the atmosphere satisfies a power law, then the exponent must be less than 3 for heating to overcome adiabatic cooling. Both the simulations of the outburst and the model atmosphere fits to the observed energy distributions, however, imply that the exponent is greater than or = 3 during the early phases of the outburst. Nevertheless, for a value of the exponent of 2, we predict the time when hot coronal gas can form during the expansion phases of the envelope.

  11. Von Kármán energy decay and heating of protons and electrons in a kinetic turbulent plasma.

    PubMed

    Wu, P; Wan, M; Matthaeus, W H; Shay, M A; Swisdak, M

    2013-09-20

    Decay in time of undriven weakly collisional kinetic plasma turbulence in systems large compared to the ion kinetic scales is investigated using fully electromagnetic particle-in-cell simulations initiated with transverse flow and magnetic disturbances, constant density, and a strong guide field. The observed energy decay is consistent with the von Kármán hypothesis of similarity decay, in a formulation adapted to magnetohydrodyamics. Kinetic dissipation occurs at small scales, but the overall rate is apparently controlled by large scale dynamics. At small turbulence amplitudes the electrons are preferentially heated. At larger amplitudes proton heating is the dominant effect. In the solar wind and corona the protons are typically hotter, suggesting that these natural systems are in the large amplitude turbulence regime. PMID:24093244

  12. von Kármán Energy Decay and Heating of Protons and Electrons in a Kinetic Turbulent Plasma

    NASA Astrophysics Data System (ADS)

    Wu, P.; Wan, M.; Matthaeus, W. H.; Shay, M. A.; Swisdak, M.

    2013-09-01

    Decay in time of undriven weakly collisional kinetic plasma turbulence in systems large compared to the ion kinetic scales is investigated using fully electromagnetic particle-in-cell simulations initiated with transverse flow and magnetic disturbances, constant density, and a strong guide field. The observed energy decay is consistent with the von Kármán hypothesis of similarity decay, in a formulation adapted to magnetohydrodyamics. Kinetic dissipation occurs at small scales, but the overall rate is apparently controlled by large scale dynamics. At small turbulence amplitudes the electrons are preferentially heated. At larger amplitudes proton heating is the dominant effect. In the solar wind and corona the protons are typically hotter, suggesting that these natural systems are in the large amplitude turbulence regime.

  13. Advanced Energy and Water Recovery Technology from Low Grade Waste Heat

    SciTech Connect

    Dexin Wang

    2011-12-19

    The project has developed a nanoporous membrane based water vapor separation technology that can be used for recovering energy and water from low-temperature industrial waste gas streams with high moisture contents. This kind of exhaust stream is widely present in many industrial processes including the forest products and paper industry, food industry, chemical industry, cement industry, metal industry, and petroleum industry. The technology can recover not only the sensible heat but also high-purity water along with its considerable latent heat. Waste heats from such streams are considered very difficult to recover by conventional technology because of poor heat transfer performance of heat-exchanger type equipment at low temperature and moisture-related corrosion issues. During the one-year Concept Definition stage of the project, the goal was to prove the concept and technology in the laboratory and identify any issues that need to be addressed in future development of this technology. In this project, computational modeling and simulation have been conducted to investigate the performance of a nanoporous material based technology, transport membrane condenser (TMC), for waste heat and water recovery from low grade industrial flue gases. A series of theoretical and computational analyses have provided insight and support in advanced TMC design and experiments. Experimental study revealed condensation and convection through the porous membrane bundle was greatly improved over an impermeable tube bundle, because of the membrane capillary condensation mechanism and the continuous evacuation of the condensate film or droplets through the membrane pores. Convection Nusselt number in flue gas side for the porous membrane tube bundle is 50% to 80% higher than those for the impermeable stainless steel tube bundle. The condensation rates for the porous membrane tube bundle also increase 60% to 80%. Parametric study for the porous membrane tube bundle heat transfer

  14. Laser surface modification of medical grade alloys for reduced heating in a magnetic resonance imaging environment

    SciTech Connect

    Benafan, O. E-mail: raj@ucf.edu; Vaidyanathan, R. E-mail: raj@ucf.edu; Chen, S.-Y.; Kar, A.

    2015-12-15

    Nanoscale surface modification of medical grade metallic alloys was conducted using a neodymium-doped yttrium aluminum garnet laser-based dopant diffusion technique. The objective of this approach was to minimize the induction heating by reducing the absorbed radio frequency field. Such an approach is advantageous in that the dopant is diffused into the alloy and is not susceptible to detachment or spallation as would an externally applied coating, and is expected to not deteriorate the mechanical and electrical properties of the base alloy or device. Experiments were conducted using a controlled environment laser system with the ability to control laser properties (i.e., laser power, spot size, and irradiation time) and dopant characteristics (i.e., temperature, concentration, and pressure). The reflective and transmissive properties of both the doped and untreated samples were measured in a radio frequency (63.86 MHz) magnetic field using a system comprising a high power signal generator, a localized magnetic field source and sensor, and a signal analyzer. The results indicate an increase in the reflectivity of the laser-treated samples compared to untreated samples. The effect of reflectivity on the heating of the alloys is investigated through a mathematical model incorporating Maxwell’s equations and heat conduction.

  15. Laser surface modification of medical grade alloys for reduced heating in a magnetic resonance imaging environment.

    PubMed

    Benafan, O; Chen, S-Y; Kar, A; Vaidyanathan, R

    2015-12-01

    Nanoscale surface modification of medical grade metallic alloys was conducted using a neodymium-doped yttrium aluminum garnet laser-based dopant diffusion technique. The objective of this approach was to minimize the induction heating by reducing the absorbed radio frequency field. Such an approach is advantageous in that the dopant is diffused into the alloy and is not susceptible to detachment or spallation as would an externally applied coating, and is expected to not deteriorate the mechanical and electrical properties of the base alloy or device. Experiments were conducted using a controlled environment laser system with the ability to control laser properties (i.e., laser power, spot size, and irradiation time) and dopant characteristics (i.e., temperature, concentration, and pressure). The reflective and transmissive properties of both the doped and untreated samples were measured in a radio frequency (63.86 MHz) magnetic field using a system comprising a high power signal generator, a localized magnetic field source and sensor, and a signal analyzer. The results indicate an increase in the reflectivity of the laser-treated samples compared to untreated samples. The effect of reflectivity on the heating of the alloys is investigated through a mathematical model incorporating Maxwell's equations and heat conduction. PMID:26724043

  16. Laser surface modification of medical grade alloys for reduced heating in a magnetic resonance imaging environment

    NASA Astrophysics Data System (ADS)

    Benafan, O.; Chen, S.-Y.; Kar, A.; Vaidyanathan, R.

    2015-12-01

    Nanoscale surface modification of medical grade metallic alloys was conducted using a neodymium-doped yttrium aluminum garnet laser-based dopant diffusion technique. The objective of this approach was to minimize the induction heating by reducing the absorbed radio frequency field. Such an approach is advantageous in that the dopant is diffused into the alloy and is not susceptible to detachment or spallation as would an externally applied coating, and is expected to not deteriorate the mechanical and electrical properties of the base alloy or device. Experiments were conducted using a controlled environment laser system with the ability to control laser properties (i.e., laser power, spot size, and irradiation time) and dopant characteristics (i.e., temperature, concentration, and pressure). The reflective and transmissive properties of both the doped and untreated samples were measured in a radio frequency (63.86 MHz) magnetic field using a system comprising a high power signal generator, a localized magnetic field source and sensor, and a signal analyzer. The results indicate an increase in the reflectivity of the laser-treated samples compared to untreated samples. The effect of reflectivity on the heating of the alloys is investigated through a mathematical model incorporating Maxwell's equations and heat conduction.

  17. Effect of Joule heating and thermal radiation in flow of third grade fluid over radiative surface.

    PubMed

    Hayat, Tasawar; Shafiq, Anum; Alsaedi, Ahmed

    2014-01-01

    This article addresses the boundary layer flow and heat transfer in third grade fluid over an unsteady permeable stretching sheet. The transverse magnetic and electric fields in the momentum equations are considered. Thermal boundary layer equation includes both viscous and Ohmic dissipations. The related nonlinear partial differential system is reduced first into ordinary differential system and then solved for the series solutions. The dependence of velocity and temperature profiles on the various parameters are shown and discussed by sketching graphs. Expressions of skin friction coefficient and local Nusselt number are calculated and analyzed. Numerical values of skin friction coefficient and Nusselt number are tabulated and examined. It is observed that both velocity and temperature increases in presence of electric field. Further the temperature is increased due to the radiation parameter. Thermal boundary layer thickness increases by increasing Eckert number. PMID:24454694

  18. Effect of Joule Heating and Thermal Radiation in Flow of Third Grade Fluid over Radiative Surface

    PubMed Central

    Hayat, Tasawar; Shafiq, Anum; Alsaedi, Ahmed

    2014-01-01

    This article addresses the boundary layer flow and heat transfer in third grade fluid over an unsteady permeable stretching sheet. The transverse magnetic and electric fields in the momentum equations are considered. Thermal boundary layer equation includes both viscous and Ohmic dissipations. The related nonlinear partial differential system is reduced first into ordinary differential system and then solved for the series solutions. The dependence of velocity and temperature profiles on the various parameters are shown and discussed by sketching graphs. Expressions of skin friction coefficient and local Nusselt number are calculated and analyzed. Numerical values of skin friction coefficient and Nusselt number are tabulated and examined. It is observed that both velocity and temperature increases in presence of electric field. Further the temperature is increased due to the radiation parameter. Thermal boundary layer thickness increases by increasing Eckert number. PMID:24454694

  19. Shutdown Decay Heat Removal analysis of a Westinghouse 3-loop pressurized water reactor: Case study

    SciTech Connect

    Sanders, G.A.; Ericson, D.M. Jr.; Cramond, W.R.

    1987-03-01

    This is one of six case studies for USI A-45 Decay Heat Removal (DHR) Requirements. The purpose of this study is to identify any potential vulnerabilities in the DHR systems of a typical Westinghouse 3-loop PWR, to suggest possible modifications to improve the DHR capability, and to assess the value and impact of the most promising alternatives to the existing DHR systems. The systems analysis considered small LOCAs and transient internal initiating events, and seismic, fire, extreme wind, internal and external flood, and lightning external events. A full-scale systems analysis was performed with detailed fault trees and event trees including support system dependencies. The system analysis results were extrapolated into release categories using applicable past PRA phenomenological results and improved containment failure mode probabilities. Public consequences were estimated using site specific CRAC2 calculations. The Value-Impact (VI) analysis of possible alternatives considered both onsite and offsite impacts arriving at several risk measures such as averted population dose out to a 50-mile radius and dollars per person rem averted. Uncertainties in the VI analysis are discussed and the issues of feed and bleed and secondary blowdown are analyzed.

  20. Shutdown decay heat removal analysis of a Babcock and Wilcox pressurized water reactor: Case study

    SciTech Connect

    Cramond, W.R.; Ericson, D.M. Jr.; Sanders, G.A.

    1987-03-01

    This is one of six case studies for USI A-45 Decay Heat Removal (DHR) Requirements. The purpose of this study is to identify any potential vulnerabilities in the DHR systems of a typical Babcock and Wilcox PWR, to suggest possible modifications to improve the DHR capability, and to assess the value and impact of the most promising alternatives to the existing DHR systems. The systems analysis considered small LOCAs and transient internal initiating events, and seismic, fire, extreme wind, internal and external flood, and lightning external events. A full-scale systems analysis was performed with detailed fault trees and event trees including support system dependencies. The system analysis results were extrapolated into release categories using applicable past PRA phenomenological results and improved containment failure mode probabilities. Public consequences were estimated using site specific CRAC2 calculations. The Value-Impact (VI) analysis of possible alternatives considered both onsite and offsite impacts arriving at several risk measures such as averted population dose out to a 50-mile radius and dollars per person rem averted. Uncertainties in the VI analysis are discussed and the issues of feed and bleed and secondary blowdown are analyzed.

  1. Shutdown decay heat removal analysis of a Combustion Engineering 2-loop pressurized water reactor: Case study

    SciTech Connect

    Cramond, W.R.; Ericson, D.M. Jr.; Sanders, G.A.

    1987-08-01

    This is one of six case studies for USI A-45 Decay Heat Removal (DHR) Requirements. The purpose of this study is to identify any potential vulnerabilities in the DHR systems of a typical Combustion Engineering 2-loop PWR, to suggest possible modifications to improve the DHR capability, and to assess the value and impact of the most promising alternatives to the existing DHR systems. The systems analysis considered small LOCAs and transient internal initiating events, and seismic, fire, extreme wind, internal and external flood, and lightning external events. A full-scale systems analysis was performed with detailed fault trees and event trees including support system dependencies. The system analysis results were extrapolated into release categories using applicable past PRA phenomenological results and improved containment failure mode probabilities. Public consequences were estimated using site specific CRAC2 calculations. The Value-Impact (VI) analysis of possible alternatives considered both onsite and offsite impacts arriving at several risk measures such as averted population dose out to a 50-mile radius and dollars per person rem averted. Uncertainties in the VI analysis are discussed and the issues of feed and bleed and secondary blowdown are analyzed.

  2. Shutdown decay heat removal analysis of a Westinghouse 2-loop pressurized water reactor: Case study

    SciTech Connect

    Cramond, W.R.; Ericson, D.M. Jr.; Sanders, G.A.

    1987-03-01

    This is one of six case studies for USI A-45 Decay Heat Removal (DHR) Requirements. The purpose of this study is to identify any potential vulnerabilities in the DHR systems of a typical Westinghouse 2-loop PWR, to suggest possible modifications to improve the DHR capability, and to assess the value and impact of the most promising alternatives to the existing DHR systems. The systems analysis considered small LOCAs and transient internal initiating events, and seismic, fire, extreme wind, internal and external flood, and lightning external events. A full-scale systems analysis was performed with detailed fault trees and event trees including support system dependencies. The system analysis results were extrapolated into release categories using applicable past PRA phenomenological results and improved containment failure mode probabilities. Public consequences were estimated using site specific CRAC2 calculations. The Value-Impact (VI) analysis of possible alternatives considered both onsite and offsite impacts arriving at several risk measures such as averted population dose out to a 50-mile radius and dollars per person rem averted. Uncertainties in the VI analysis are discussed and the issues of feed and bleed and secondary blowdown are analyzed.

  3. Closeout of IE Bulletin 80-12: decay heat removal system operability

    SciTech Connect

    Foley, W.J.; Dean, R.S.; Hennick, A.

    1985-06-01

    On April 19, 1980, decay heat removal (DHR) capability was lost at Davis-Besse 1 for approximately two and one-half hours in a refueling mode. Typically for that mode, many systems and components were out of service for maintanance and testing or were deactivated to preclude inadvertent actuation. IE Bulletin 80-12 was issued May 9, 1980 for action by licensees of operating pressurized water reactors (PWRs); it was issued for information to nuclear power facilities other than operating PWRs. The intent of the bulletin ws to improve nuclear plant safety by reducing the likelihood of losing DHR capability in PWRs, especially when some DHR components are unavailable because of maintenance activities during refueling and cold shutdown modes of operation. A related NRR Generic Letter was issued June 11, 1980 to licensees of operating PWRs, requesting amendment of technical specifications to ensure long-term maintenance of DHR capability. Evaluation of utility responses and NRC/IE inspection reports indicates that the bulletin can be closed out per specific criteria for 33 (75%) of the 44 affected facilities.

  4. Simulation of loss-of-decay heat removal with MAAP 3. 0B

    SciTech Connect

    Plys, M.G.; Paik, C.Y.

    1989-01-01

    Loss-of-decay heat removal (DHR) during nonpower operation and its potential consequences have been of increasing concern to US pressurized water reactor (PWR) owners and regulators. Regulatory action prompted by the April 10, 1987, loss of DHR at Diablo Canyon Unit 2 cited 37 instances of loss of DHR events attributed to inadequate reactor coolant system (RCS) water level. In the Diablo Canyon event, 7 days after shutdown for its first refueling outage, boiling and pressurization of the primary system began after {approximately}1 h after loss of DHR, which was reestablished after another 20 min. This paper describes the modification and application of the Modular Accident Analysis Program (MAAP) version 3.0B (Ref. 3) for simulation of loss of DHR scenarios. MAAP 30.B, maintained by the Electric Power Research Institute and available to most US and many foreign utilities, is designed to perform coupled thermal-hydraulic and fission product calculations for severe-accident analysis. In this application, the capabilities of MAAP are extended to allow simulation of a shutdown plant state to calculate the time to core uncovery and fuel damage. Operator actions to mitigate or terminate the accident can be simulated, and timing of key events given by MAAP is useful for the evaluation of procedures.

  5. Effect of repeated structural recrystallization of grade 20 steel on corrosion resistance of pipes of heating surfaces

    NASA Astrophysics Data System (ADS)

    Pomazova, A. V.; Panova, T. V.; Gering, G. I.

    2015-04-01

    The necessity to enhance the operating characteristics of boiler steels is related to a continuous increase in corrosion damages of pipes of heating surfaces. Therefore, the actual task remains the development of ways to enhance the corrosion resistance of pipes made of grade 20, which are used as heat-absorbing elements in heat power engineering. The effect of cyclic modes of normalization (repeated structural recrystallization) on microstructural characteristics and the mechanical and corrosion properties of grade 20 steel in accordance with the regulatory requirements for products of this kind is studied. It is established that twofold normalization for grade 20 carbon steel is the optimum heat treatment mode for equalizing the ferrite grain sizes and decreasing the corrosion rate. It is revealed that this heat treatment mode increases the inequigranularity factor by three times in comparison with the original magnitude. Subsequent normalization cycles result in the formation of rejected microstructures and a decrease in mechanical properties of metal. The increased homogeneity of the microstructure at the double normalization decreases the corrosion rate by 38-51% of the original magnitude. The obtained results can be used for prolongation of the operation life by a decrease in the corrosion rate in pipes normalized twice as well as for the calculation of the remaining life of heating surfaces of boilers of heat power plants.

  6. Development of a water boil-off spent-fuel calorimeter system. [To measure decay heat generation rate

    SciTech Connect

    Creer, J.M.; Shupe, J.W. Jr.

    1981-05-01

    A calorimeter system was developed to measure decay heat generation rates of unmodified spent fuel assemblies from commercial nuclear reactors. The system was designed, fabricated, and successfully tested using the following specifications: capacity of one BWR or PWR spent fuel assembly; decay heat generation range 0.1 to 2.5 kW; measurement time of < 12 h; and an accuracy of +-10% or better. The system was acceptance tested using a dc reference heater to simulate spent fuel assembly heat generation rates. Results of these tests indicated that the system could be used to measure heat generation rates between 0.5 and 2.5 kW within +- 5%. Measurements of heat generation rates of approx. 0.1 kW were obtained within +- 15%. The calorimeter system has the potential to permit measurements of heat generation rates of spent fuel assemblies and other devices in the 12- to 14-kW range. Results of calorimetry of a Turkey Point spent fuel assembly indicated that the assembly was generating approx. 1.55 kW.

  7. Effect of heat treatment on microstructure and hardness of Grade 91 steel

    DOE PAGESBeta

    Shrestha, Triratna; Alsagabi, Sultan; Charit, Indrajit; Potirniche, Gabriel; Glazoff, Michael

    2015-01-21

    The modified 9Cr-1Mo steel (Grade 91) is a material of choice in fossil-fuel-fired power plants with increased efficiency, service life, and reduction in emission of greenhouse gases. It is also considered a prospective material for the Next Generation Nuclear Power Plant for application in reactor pressure vessels at temperatures up to 650°C. In this paper, heat treatment of the modified 9Cr-1Mo steel was studied by normalizing and tempering the steel at various temperatures and times, with the ultimate goal of improving its creep resistance and optimizing material hardness. The microstructural evolution of the heat treated steels was correlated with themore » differential scanning calorimetric results. Optical microscopy, scanning and transmission electron microscopy in conjunction with microhardness profiles and calorimetric plots were used to understand the evolution of microstructure including precipitate structures in modified 9Cr-1Mo steel and relate it to the mechanical behavior of the steel. Thermo-CalcTM calculations were used to support experimental work and provide guidance in terms of the precipitate stability and microstructural evolution. Furthermore, the carbon isopleth and temperature dependencies of the volume fraction of different precipitates were constructed. The predicted and experimentally observed results were found to be in good agreement.« less

  8. Effect of heat treatment on microstructure and hardness of Grade 91 steel

    SciTech Connect

    Shrestha, Triratna; Alsagabi, Sultan; Charit, Indrajit; Potirniche, Gabriel; Glazoff, Michael

    2015-01-21

    The modified 9Cr-1Mo steel (Grade 91) is a material of choice in fossil-fuel-fired power plants with increased efficiency, service life, and reduction in emission of greenhouse gases. It is also considered a prospective material for the Next Generation Nuclear Power Plant for application in reactor pressure vessels at temperatures up to 650°C. In this paper, heat treatment of the modified 9Cr-1Mo steel was studied by normalizing and tempering the steel at various temperatures and times, with the ultimate goal of improving its creep resistance and optimizing material hardness. The microstructural evolution of the heat treated steels was correlated with the differential scanning calorimetric results. Optical microscopy, scanning and transmission electron microscopy in conjunction with microhardness profiles and calorimetric plots were used to understand the evolution of microstructure including precipitate structures in modified 9Cr-1Mo steel and relate it to the mechanical behavior of the steel. Thermo-CalcTM calculations were used to support experimental work and provide guidance in terms of the precipitate stability and microstructural evolution. Furthermore, the carbon isopleth and temperature dependencies of the volume fraction of different precipitates were constructed. The predicted and experimentally observed results were found to be in good agreement.

  9. A dynamic model for the optimization of oscillatory low grade heat engines

    SciTech Connect

    Markides, Christos N.; Smith, Thomas C. B.

    2015-01-22

    The efficiency of a thermodynamic system is a key quantity on which its usefulness and wider application relies. This is especially true for a device that operates with marginal energy sources and close to ambient temperatures. Various definitions of efficiency are available, each of which reveals a certain performance characteristic of a device. Of these, some consider only the thermodynamic cycle undergone by the working fluid, whereas others contain additional information, including relevant internal components of the device that are not part of the thermodynamic cycle. Yet others attempt to factor out the conditions of the surroundings with which the device is interfacing thermally during operation. In this paper we present a simple approach for the modeling of complex oscillatory thermal-fluid systems capable of converting low grade heat into useful work. We apply the approach to the NIFTE, a novel low temperature difference heat utilization technology currently under development. We use the results from the model to calculate various efficiencies and comment on the usefulness of the different definitions in revealing performance characteristics. We show that the approach can be applied to make design optimization decisions, and suggest features for optimal efficiency of the NIFTE.

  10. The effect of air leakage and heat exchange on the decay of entrapped air pocket slamming oscillations

    NASA Astrophysics Data System (ADS)

    Abrahamsen, Bjørn C.; Faltinsen, Odd M.

    2011-10-01

    The phenomenon studied in this work is that of an air pocket entrapped by a free surface water wave inside a rectangular tank at a high filling level. The wave, which is a gravity wave, is caused by forced horizontal motion which is constructed in a particular way, in order to entrap an air pocket as it approaches the upper left corner of the tank. As the wave touches the roof, the air is compressed and starts to oscillate. The oscillations resemble, to some extent, the free oscillations of an underdamped mass-spring system, where the mass is related to the generalized added mass effect of the water pressure associated with the air pocket oscillations. The stiffness is due to the compressibility of the air. The reason for the damping or, more generally, the decay of the air pocket oscillations is less understood. Air leakage has been proposed as one possible reason for this decay. In this work, the role of air leakage is found not to be the reason for the decay of the air pocket oscillations, because it is not present during major parts of the impact. However, by drilling holes in the roof of the tank, the effect of leakage during the oscillations is proven to cause decay. To explain the physical source of the decay of the oscillations, damping due to heat transfer to and from the air pocket is investigated through an analytical one-dimensional steady-state model. The damping due to heat transfer is observed to play an important role. The obtained understanding of the mechanisms causing the decay of the air-pocket impact at the upper corner is believed to be relevant to other types of impacts, particularly the entrapment of air pockets on walls by breaking waves.

  11. Unsteady Flow of Third Grade Fluid over an Oscillatory Stretching Sheet with Thermal Radiation and Heat Source/Sink

    NASA Astrophysics Data System (ADS)

    Ali, Nasir; Khan, Sami Ullah; Abbas, Zaheer

    2015-12-01

    The aim of this article is to investigate the unsteady boundary layer flow and heat transfer analysis in a third grade fluid over an oscillatory stretching sheet under the influences of thermal radiation and heat source/sink. The convective boundary condition at the sheet is imposed to determine the temperature distribution. Homotopy analysis method (HAM) is used to solve dimensionless nonlinear partial differential equations. The effects of involved parameters on both velocity and temperature fields are illustrated in detail through various plots. It is found that the amplitude of velocity decreases by increasing the ratio of the oscillation frequency of the sheet to its stretching rate and Hartmann number while it increases by increasing the third grade fluid parameter. On contrary, the temperature field is found to be a decreasing function of the third grade fluid parameter.

  12. Thermal Energy Consumption in the Heat-Technology Production of Solid Composite Fuel From Low-Grade Raw Materials

    NASA Astrophysics Data System (ADS)

    Tabakaev, Roman; Astafev, Alexander; Kazakov, Alexander; Zavorin, Alexander

    2016-02-01

    An evaluation is made of the thermal energy consumed in the heat-technology production of solid composite fuel from low-grade organic raw materials. It is shown that the heat of decomposition of the organic mass and the combustion of the by-products of heat-technology may be sufficient to cover all the energy needs for processing peat, brown coal and wood chips. Producing solid composite fuel from sapropel requires external resources to compensate for part of the heat consumed. Calculations show that it is possible for the thermal processing of raw materials to proceed autothermally due to the heat of decomposition when the moisture content at the reactor inlet is limited: for peat it should be no more than 35%, 54% for brown coal, and 37% for wood chips. The low heat of decomposition of the sapropel organic mass means that its thermal processing cannot proceed autothermally.

  13. [Urban heat island intensity and its grading in Liaoning Province of Northeast China].

    PubMed

    Li, Li-Guang; Wang, Hong-Bo; Jia, Qing-Yu; Lü, Guo-Hong; Wang, Xiao-Ying; Zhang, Yu-Shu; Ai, Jing-Feng

    2012-05-01

    According to the recorded air temperature data and their continuity of each weather station, the location of each weather station, the numbers of and the distances among the weather stations, and the records on the weather stations migration, several weather stations in Liaoning Province were selected as the urban and rural representative stations to study the characteristics of urban heat island (UHI) intensity in the province. Based on the annual and monthly air temperature data of the representative stations, the ranges and amplitudes of the UHI intensity were analyzed, and the grades of the UHI intensity were classified. The Tieling station, Dalian station, Anshan station, Chaoyang station, Dandong station, and Jinzhou station and the 18 stations including Tai' an station were selected as the representative urban and rural weather stations, respectively. In 1980-2009, the changes of the annual UHI intensity in the 6 representative cities differed. The annual UHI intensity in Tieling was in a decreasing trend, while that in the other five cities was in an increasing trend. The UHI intensity was strong in Tieling but weak in Dalian. The changes of the monthly UHI intensity in the 6 representative cities also differed. The distribution of the monthly UHI intensity in Dandong, Jinzhou and Tieling took a "U" shape, with the maximum and minimum appeared in January and in May-August, respectively, indicating that the monthly UHI intensity was strong in winter and weak in summer. The ranges of the annual and monthly UHI intensity in the 6 cities were 0.57-2.15 degrees C and -0.70-4.60 degrees C, and the ranges of 0.5-2.0 degrees C accounted for 97.8% and 72.3%, respectively. The UHI intensity in the province could be classified into 4 grades, i. e., weak, strong, stronger and strongest. PMID:22919847

  14. Harvesting low-grade heat energy using thermo-osmotic vapour transport through nanoporous membranes

    NASA Astrophysics Data System (ADS)

    Straub, Anthony P.; Yip, Ngai Yin; Lin, Shihong; Lee, Jongho; Elimelech, Menachem

    2016-07-01

    Low-grade heat from sources below 100 ∘C offers a vast quantity of energy. The ability to extract this energy, however, is limited with existing technologies as they are not well-suited to harvest energy from sources with variable heat output or with a small temperature difference between the source and the environment. Here, we present a process for extracting energy from low-grade heat sources utilizing hydrophobic, nanoporous membranes that trap air within their pores when submerged in a liquid. By driving a thermo-osmotic vapour flux across the membrane from a hot reservoir to a pressurized cold reservoir, heat energy can be converted to mechanical work. We demonstrate operation of air-trapping membranes under hydraulic pressures up to 13 bar, show that power densities as high as 3.53 ± 0.29 W m‑2 are achievable with a 60 ∘C heat source and a 20 ∘C heat sink, and estimate the efficiency of a full-scale system. The results demonstrate a promising process to harvest energy from low-temperature differences (<40 ∘C) and fluctuating heat sources.

  15. HEat Decay Data Repository Footprint for Thermal-Hydrologic and Conduction-Only Models for TSPA-SR

    SciTech Connect

    N.D. Francis

    2000-04-24

    The repository heat decay data contained within this calculation is specified for both mountain-scale and drift-scale thermal-hydrologic (TH), thermal-hydrologic-mechanical (THM), and thermal-hydrologic-chemical (THC) simulations used in total systems performance assessments (TSPA). Repository thermal output data, and how it decays in time, is required by the models that compute changes to the geologic system as a result of a heat addition. The mountain-scale problem requires a repository-wide waste stream including the total heat output of each fuel type to be emplaced in the repository. These models apply a smeared heat source over a predefined repository footprint area specified in the model. The drift-scale problem requires the heat output of a number of representative (specific) waste package types. These models apply specific waste package heat outputs resolved at the scale of the waste package itself. The results of this calculation will supply details of the repository heat load for each model type. It also provides a schematic of the repository footprint outlines for the License Application Design Selection (LADS), the total repository footprint for TSPA site recommendation (SR) including the contingency area, and the actual loaded repository footprint. This calculation is performed under procedure AP-3.12Q, Rev. 0/ICN 0, Calculations. It is directed by the development plan TDP-MGR-HS-000001 (CRWMS M&O 1999f) which was developed under procedure AP-2.13Q, Rev. 0/ICN 1, Technical Product Development Plans for use in Performance Assessment activities.

  16. Decay heat of sodium fast reactor: Comparison of experimental measurements on the PHENIX reactor with calculations performed with the French DARWIN package

    SciTech Connect

    Benoit, J. C.; Bourdot, P.; Eschbach, R.; Boucher, L.; Pascal, V.; Fontaine, B.; Martin, L.; Serot, O.

    2012-07-01

    A Decay Heat (DH) experiment on the whole core of the French Sodium-Cooled Fast Reactor PHENIX has been conducted in May 2008. The measurements began an hour and a half after the shutdown of the reactor and lasted twelve days. It is one of the experiments used for the experimental validation of the depletion code DARWIN thereby confirming the excellent performance of the aforementioned code. Discrepancies between measured and calculated decay heat do not exceed 8%. (authors)

  17. Evaluation of heat generation by radioactive decay of sedimentary rocks in Eastern Desert and Nile Valley, Egypt.

    PubMed

    Abbady, Adel G E

    2010-10-01

    Radioactive heat-production (RHP) data of sedimentary outcrops in Gebel Anz (Eastern Desert) and Gebel Sarai (Nile Valley) are presented. A total of 103 rock samples were investigated, covering all major rock types of the areas. RHP were derived from uranium, thorium and potassium concentrations measured from gamma-radiation originating from the decay of (214)Bi ((238)U series), (208)Tl ((232)Th series) and the primary decay of (40)K, obtained with a NaI (Tl) detector. The heat-production rate of Gebel Anz ranges from 0.94 (Nubai Sandstone ) to 5.22 microW m(-3) (Duwi Formation). In Gebel Sarai it varies from 0.82 (Esna Shale) to 7 microW m(-3) (Duwi Formation). The contribution due to U is about 62%, from Th is 34% and 4% from K in Gebel Anz. The corresponding values in Gebel Sarai are 69.6%, 26.9% and 3.5%, respectively. These data can be used to discuss the effects of the lateral variation of the RHP rate on the heat flux and the temperature fields in the upper crust. PMID:20472452

  18. Experimental investigations on decay heat removal in advanced nuclear reactors using single heater rod test facility: Air alone in the annular gap

    SciTech Connect

    Bopche, Santosh B.; Sridharan, Arunkumar

    2010-11-15

    During a loss of coolant accident in nuclear reactors, radiation heat transfer accounts for a significant amount of the total heat transfer in the fuel bundle. In case of heavy water moderator nuclear reactors, the decay heat of a fuel bundle enclosed in the pressure tube and outer concentric calandria tube can be transferred to the moderator. Radiation heat transfer plays a significant role in removal of decay heat from the fuel rods to the moderator, which is available outside the calandria tube. A single heater rod test facility is designed and fabricated as a part of preliminary investigations. The objective is to anticipate the capability of moderator to remove decay heat, from the reactor core, generated after shut down. The present paper focuses mainly on the role of moderator in removal of decay heat, for situation with air alone in the annular gap of pressure tube and calandria tube. It is seen that the naturally aspirated air is capable of removing the heat generated in the system compared to the standstill air or stagnant water situations. It is also seen that the flowing moderator is capable of removing a greater fraction of heat generated by the heater rod compared to a stagnant pool of boiling moderator. (author)

  19. COMBINED ACTIVE/PASSIVE DECAY HEAT REMOVAL APPROACH FOR THE 24 MWt GAS-COOLED FAST REACTOR

    SciTech Connect

    CHENG,L.Y.; LUDEWIG, H.

    2007-06-01

    Decay heat removal at depressurized shutdown conditions has been regarded as one of the key areas where significant improvement in passive response was targeted for the GEN IV GFR over the GCFR designs of thirty years ago. It has been recognized that the poor heat transfer characteristics of gas coolant at lower pressures needed to be accommodated in the GEN IV design. The design envelope has therefore been extended to include a station blackout sequence simultaneous with a small break/leak. After an exploratory phase of scoping analysis in this project, together with CEA of France, it was decided that natural convection would be selected as the passive decay heat removal approach of preference. Furthermore, a double vessel/containment option, similar to the double vessel/guard vessel approach of the SFR, was selected as the means of design implementation to reduce the PRA risks of the depressurization accident. However additional calculations in conjunction with CEA showed that there was an economic penalty in terms of decay heat removal system heat exchanger size, elevation heights for thermal centers, and most of all in guard containment back pressure for complete reliance on natural convection only. The back pressure ranges complicated the design requirements for the guard containment. Recognizing that the definition of a loss-of-coolant-accident in the GFR is a misnomer, since gas coolant will always be present, and the availability of some driven blower would reduce fuel temperature transients significantly; it was decided instead to aim for a hybrid active/passive combination approach to the selected BDBA. Complete natural convection only would still be relied on for decay heat removal but only after the first twenty four hours after the initiation of the accident. During the first twenty four hour period an actively powered blower would be relied on to provide the emergency decay power removal. However the power requirements of the active blower

  20. Heat transfer analysis in a second grade fluid over and oscillating vertical plate using fractional Caputo-Fabrizio derivatives

    NASA Astrophysics Data System (ADS)

    Shah, Nehad Ali; Khan, Ilyas

    2016-07-01

    This paper presents a Caputo-Fabrizio fractional derivatives approach to the thermal analysis of a second grade fluid over an infinite oscillating vertical flat plate. Together with an oscillating boundary motion, the heat transfer is caused by the buoyancy force induced by temperature differences between the plate and the fluid. Closed form solutions of the fluid velocity and temperature are obtained by means of the Laplace transform. The solutions of ordinary second grade and Newtonian fluids corresponding to time derivatives of integer and fractional orders are obtained as particular cases of the present solutions. Numerical computations and graphical illustrations are used in order to study the effects of the Caputo-Fabrizio time-fractional parameter α, the material parameter α _2 , and the Prandtl and Grashof numbers on the velocity field. A comparison for time derivative of integer order versus fractional order is shown graphically for both Newtonian and second grade fluids. It is found that fractional fluids (second grade and Newtonian) have highest velocities. This shows that the fractional parameter enhances the fluid flow.

  1. Control of reactor coolant flow path during reactor decay heat removal

    DOEpatents

    Hunsbedt, Anstein N.

    1988-01-01

    An improved reactor vessel auxiliary cooling system for a sodium cooled nuclear reactor is disclosed. The sodium cooled nuclear reactor is of the type having a reactor vessel liner separating the reactor hot pool on the upstream side of an intermediate heat exchanger and the reactor cold pool on the downstream side of the intermediate heat exchanger. The improvement includes a flow path across the reactor vessel liner flow gap which dissipates core heat across the reactor vessel and containment vessel responsive to a casualty including the loss of normal heat removal paths and associated shutdown of the main coolant liquid sodium pumps. In normal operation, the reactor vessel cold pool is inlet to the suction side of coolant liquid sodium pumps, these pumps being of the electromagnetic variety. The pumps discharge through the core into the reactor hot pool and then through an intermediate heat exchanger where the heat generated in the reactor core is discharged. Upon outlet from the heat exchanger, the sodium is returned to the reactor cold pool. The improvement includes placing a jet pump across the reactor vessel liner flow gap, pumping a small flow of liquid sodium from the lower pressure cold pool into the hot pool. The jet pump has a small high pressure driving stream diverted from the high pressure side of the reactor pumps. During normal operation, the jet pumps supplement the normal reactor pressure differential from the lower pressure cold pool to the hot pool. Upon the occurrence of a casualty involving loss of coolant pump pressure, and immediate cooling circuit is established by the back flow of sodium through the jet pumps from the reactor vessel hot pool to the reactor vessel cold pool. The cooling circuit includes flow into the reactor vessel liner flow gap immediate the reactor vessel wall and containment vessel where optimum and immediate discharge of residual reactor heat occurs.

  2. Parametric performance of circumferentially grooved heat pipes with homogeneous and graded-porosity slab wicks at cryogenic temperatures

    NASA Technical Reports Server (NTRS)

    Groll, M.; Pittman, R. B.; Eninger, J. E.

    1975-01-01

    A recently developed, potentially high-performance nonarterial wick has been extensively tested. This slab wick has an axially varying porosity which can be tailored to match the local stress imposed on the wick. The purpose of the tests was to establish the usefulness of the graded-porosity slab wick at cryogenic temperatures between 110 K and 260 K, with methane and ethane as working fluids. For comparison, a homogeneous (i.e., uniform porosity) slab wick was also tested. The tests included: (1) maximum heat pipe performance as a function of fluid inventory, (2) maximum performance as a function of operating temperature, (3) maximum performance as a function of evaporator elevation, and (4) influence of slab wick orientation on performance. The experimental data was compared with theoretical predictions obtained with the computer program GRADE.

  3. BWR spent fuel storage cask performance test. Volume 1. Cask handling experience and decay heat, heat transfer, and shielding data

    SciTech Connect

    McKinnon, M.A.; Doman, J.W.; Tanner, J.E.; Guenther, R.J.; Creer, J.M.; King, C.E.

    1986-02-01

    This report documents a heat transfer and shielding performance test conducted on a Ridihalgh, Eggers and Associates REA 2023 boiling water reactor (BWR) spent fuel storage cask. The testing effort consisted of three parts: pretest preparations, performance testing, and post-test activities. Pretest preparations included conducting cask handling dry runs and characterizing BWR spent fuel assemblies from Nebraska Public Power District's Cooper Nuclear Station. The performance test matrix included 14 runs consisting of two loadings, two cask orientations, and three backfill environments. Post-test activities included calorimetry and axial radiation scans of selected fuel assemblies, in-basin sipping of each assembly, crud collection, video and photographic scans, and decontamination of the cask interior and exterior.

  4. Comparison of deterministic and stochastic approaches for isotopic concentration and decay heat uncertainty quantification on elementary fission pulse

    NASA Astrophysics Data System (ADS)

    Lahaye, S.; Huynh, T. D.; Tsilanizara, A.

    2016-03-01

    Uncertainty quantification of interest outputs in nuclear fuel cycle is an important issue for nuclear safety, from nuclear facilities to long term deposits. Most of those outputs are functions of the isotopic vector density which is estimated by fuel cycle codes, such as DARWIN/PEPIN2, MENDEL, ORIGEN or FISPACT. CEA code systems DARWIN/PEPIN2 and MENDEL propagate by two different methods the uncertainty from nuclear data inputs to isotopic concentrations and decay heat. This paper shows comparisons between those two codes on a Uranium-235 thermal fission pulse. Effects of nuclear data evaluation's choice (ENDF/B-VII.1, JEFF-3.1.1 and JENDL-2011) is inspected in this paper. All results show good agreement between both codes and methods, ensuring the reliability of both approaches for a given evaluation.

  5. Study on natural convection capability of liquid gallium for passive decay heat removal system (PDHRS)

    SciTech Connect

    Kang, S.; Ha, K. S.; Lee, S. W.; Park, S. D.; Kim, S. M.; Seo, H.; Kim, J. H.; Bang, I. C.

    2012-07-01

    The safety issues of the SFRs are important due to the fact that it uses sodium as a nuclear coolant, reacting vigorously with water and air. For that reason, there are efforts to seek for alternative candidates of liquid metal coolants having excellent heat transfer property and to adopt improved safety features to the SFR concepts. This study considers gallium as alternative liquid metal coolant applicable to safety features in terms of chemical activity issue of the sodium and aims to experimentally investigate the natural convection capability of gallium as a feasibility study for the development of gallium-based passive safety features in SFRs. In this paper, the design and construction of the liquid gallium natural convection loop were carried out. The experimental results of heat transfer coefficient of liquid gallium resulting in heat removal {approx}2.53 kW were compared with existing correlations and they were much lower than the correlations. To comparison of the experimental data with computer code analysis, gallium property code was developed for employing MARS-LMR (Korea version of RELAP) based on liquid gallium as working fluid. (authors)

  6. Investigation of the impact of transient heat loads applied by laser irradiation on ITER-grade tungsten

    NASA Astrophysics Data System (ADS)

    Huber, A.; Arakcheev, A.; Sergienko, G.; Steudel, I.; Wirtz, M.; Burdakov, A. V.; Coenen, J. W.; Kreter, A.; Linke, J.; Mertens, Ph; Philipps, V.; Pintsuk, G.; Reinhart, M.; Samm, U.; Shoshin, A.; Schweer, B.; Unterberg, B.; Zlobinski, M.

    2014-04-01

    Cracking thresholds and crack patterns in tungsten targets after repetitive ITER-like edge localized mode (ELM) pulses have been studied in recent simulation experiments by laser irradiation. The tungsten specimens were tested under selected conditions to quantify the thermal shock response. A Nd:YAG laser capable of delivering up to 32 J of energy per pulse with a duration of 1 ms at the fundamental wavelength λ = 1064 nm has been used to irradiate ITER-grade tungsten samples with repetitive heat loads. The laser exposures were performed for targets at room temperature (RT) as well as for targets preheated to 400 °C to measure the effects of the ELM-like loading conditions on the formation and development of cracks. The magnitude of the heat loads was 0.19, 0.38, 0.76 and 0.90 MJ m-2 (below the melting threshold) with a pulse duration of 1 ms. The tungsten surface was analysed after 100 and 1000 laser pulses to investigate the influence of material modification by plasma exposures on the cracking threshold. The observed damage threshold for ITER-grade W lies between 0.38 and 0.76 GW m-2. Continued cycling up to 1000 pulses at RT results in enhanced erosion of crack edges and crack edge melting. At the base temperature of 400 °C, the formation of cracks is suppressed.

  7. Organic Fluids and Passive Cooling in a Supercritical Rankine Cycle for Power Generation from Low Grade Heat Sources

    NASA Astrophysics Data System (ADS)

    Vidhi, Rachana

    Low grade heat sources have a large amount of thermal energy content. Due to low temperature, the conventional power generation technologies result in lower efficiency and hence cannot be used. In order to efficiently generate power, alternate methods need to be used. In this study, a supercritical organic Rankine cycle was used for heat source temperatures varying from 125°C to 200°C. Organic refrigerants with zero ozone depletion potential and their mixtures were selected as working fluid for this study while the cooling water temperature was changed from 10-25°C. Operating pressure of the cycle has been optimized for each fluid at every heat source temperature to obtain the highest thermal efficiency. Energy and exergy efficiencies of the thermodynamic cycle have been obtained as a function of heat source temperature. Efficiency of a thermodynamic cycle depends significantly on the sink temperature. At areas where water cooling is not available and ambient air temperature is high, efficient power generation from low grade heat sources may be a challenge. Use of passive cooling systems coupled with the condenser was studied, so that lower sink temperatures could be obtained. Underground tunnels, buried at a depth of few meters, were used as earth-air-heat-exchanger (EAHE) through which hot ambient air was passed. It was observed that the air temperature could be lowered by 5-10°C in the EAHE. Vertical pipes were used to lower the temperature of water by 5°C by passing it underground. Nocturnal cooling of stored water has been studied that can be used to cool the working fluid in the thermodynamic cycle. It was observed that the water temperature can be lowered by 10-20°C during the night when it is allowed to cool. The amount of water lost was calculated and was found to be approximately 0.1% over 10 days. The different passive cooling systems were studied separately and their effects on the efficiency of the thermodynamic cycle were investigated. They were

  8. Heating and melting of small icy satellites by the decay of Al-26

    NASA Technical Reports Server (NTRS)

    Prialnik, Dina; Bar-Nun, Akiva

    1990-01-01

    The effect of radiogenic heating due to Al-26 on the thermal evolution of small icy satellites is studied. The object is to find the extent of internal melting as a function of the satellite radius and of the initial Al-26 abundance. The implicit assumption, based on observations of young stars, is that planet and satellite accretion occurred on a time scale of about 10 to the 6th yr (comparable with the lifetime of Al-26. The icy satellites are modeled as spheres of initially amorphous ice, with chondritic abundances of K-40, Th-232, U-235, and U-238, corresponding to an ice/dust mass ratio of 1. Evolutionary calculations are carried out, spanning 4.5 x 10 to the 9th yr, for different combinations of the two free parameters. Heat transfer by subsolidus convection is neglected for these small satellites. The main conclusion is that the initial Al-26 abundance capable of melting icy bodies of satellite size to a significant extent is more than 10 times lower than that prevailing in the interstellar medium (or that inferred from the Ca-Al rich inclusions of the Allende meteorite, about 7 x 10 to the -7th by mass).

  9. Thermal energy storage for low grade heat in the organic Rankine cycle

    NASA Astrophysics Data System (ADS)

    Soda, Michael John

    Limits of efficiencies cause immense amounts of thermal energy in the form of waste heat to be vented to the atmosphere. Up to 60% of unrecovered waste heat is classified as low or ultra-low quality, making recovery difficult or inefficient. The organic Rankine cycle can be used to generate mechanical power and electricity from these low temperatures where other thermal cycles are impractical. A variety of organic working fluids are available to optimize the ORC for any target temperature range. San Diego State University has one such experimental ORC using R245fa, and has been experimenting with multiple expanders. One limitation of recovering waste heat is the sporadic or cyclical nature common to its production. This inconsistency makes sizing heat recovery ORC systems difficult for a variety of reasons including off-design-point efficiency loss, increased attrition from varying loads, unreliable outputs, and overall system costs. Thermal energy storage systems can address all of these issues by smoothing the thermal input to a constant and reliable level and providing back-up capacity for times when the thermal input is deactivated. Multiple types of thermal energy storage have been explored including sensible, latent, and thermochemical. Latent heat storage involves storing thermal energy in the reversible phase change of a phase change material, or PCM, and can have several advantages over other modalities including energy storage density, cost, simplicity, reliability, relatively constant temperature output, and temperature customizability. The largest obstacles to using latent heat storage include heat transfer rates, thermal cycling stability, and potentially corrosive PCMs. Targeting 86°C, the operating temperature of SDSU's experimental ORC, multiple potential materials were explored and tested as potential PCMs including Magnesium Chloride Hexahydrate (MgCl2˙6H2O), Magnesium Nitrate Hexahydrate (Mg(NO3)2˙6H 2O), montan wax, and carnauba wax. The

  10. Generation of large scale field-aligned density irregularities in ionospheric heating experiments. [electromagnetic wave decay

    NASA Technical Reports Server (NTRS)

    Fejer, J. A.

    1974-01-01

    Threshold and growth rate for stimulated Brillouin scattering are calculated for a uniform magnetoplasma. These are then compared with the threshold and growth rate of a new thermal instability in which the nonlinear Lorentz force felt by the electrons at the beat frequency of the two electromagnetic waves is replaced by a pressure force due to differential heating in the interference pattern of the pump wave and the generated electromagnetic wave. This thermal instability, which is still essentially stimulated Brillouin scattering, has a threshold which is especially low when the propagation vector of the beat wave is almost normal to the magnetic field. The threshold is then considerably lower than the threshold for normal stimulated Brillouin scattering and therefore this new instability is probably responsible for the generation of large scale field aligned irregularities and ionospheric spread F.

  11. Heating and melting of small icy satellites by the decay of 26Al

    NASA Technical Reports Server (NTRS)

    Prialnik, D.; Bar-Nun, A.; Owen, T. (Principal Investigator)

    1990-01-01

    We study the effect of radiogenic heating due to 26Al on the thermal evolution of small icy satellites. Our object is to find the extent of internal melting as a function of the satellite radius and of the initial 26Al abundance. The implicit assumption, based on observations of young stars, is that planet and satellite accretion occurred on a time scale of approximately 10(6) yr (comparable with the lifetime of 26Al). The icy satellites are modeled as spheres of initially amorphous ice, with chondritic abundances of 40K, 232Th, 235U, 238U, corresponding to an ice/dust mass ratio of 1. Evolutionary calculations are carried out, spanning 4.5 x 10(9) yr, for different combinations of the two free parameters. Heat transfer by subsolidus convection is neglected for these small satellites. Our main conclusion is that the initial 26Al abundance capable of melting icy bodies of satellite size to a significant extent is more than 10 times lower than that prevailing in the interstellar medium (or that inferred from the Ca-Al rich inclusions of the Allende meteorite, approximately 7 x 10(-7) by mass). We find, for example, that an initial 26Al mass fraction of approximately 4 x 10(-8) is sufficient for melting almost completely icy spheres with radii of 800 km, typical of the larger icy planetary satellites. We also find that for any given 26Al abundance, there is a narrow range of radii below which only marginal melting occurs and above which most of the ice melts (and refreezes later). Since extensive melting may have important consequences, such as differentiation, gas release, and volcanic activity, the effect of 26Al should be included in future studies of satellite interiors.

  12. Heating and melting of small icy satellites by the decay of 26Al.

    PubMed

    Prialnik, D; Bar-Nun, A

    1990-05-20

    We study the effect of radiogenic heating due to 26Al on the thermal evolution of small icy satellites. Our object is to find the extent of internal melting as a function of the satellite radius and of the initial 26Al abundance. The implicit assumption, based on observations of young stars, is that planet and satellite accretion occurred on a time scale of approximately 10(6) yr (comparable with the lifetime of 26Al). The icy satellites are modeled as spheres of initially amorphous ice, with chondritic abundances of 40K, 232Th, 235U, 238U, corresponding to an ice/dust mass ratio of 1. Evolutionary calculations are carried out, spanning 4.5 x 10(9) yr, for different combinations of the two free parameters. Heat transfer by subsolidus convection is neglected for these small satellites. Our main conclusion is that the initial 26Al abundance capable of melting icy bodies of satellite size to a significant extent is more than 10 times lower than that prevailing in the interstellar medium (or that inferred from the Ca-Al rich inclusions of the Allende meteorite, approximately 7 x 10(-7) by mass). We find, for example, that an initial 26Al mass fraction of approximately 4 x 10(-8) is sufficient for melting almost completely icy spheres with radii of 800 km, typical of the larger icy planetary satellites. We also find that for any given 26Al abundance, there is a narrow range of radii below which only marginal melting occurs and above which most of the ice melts (and refreezes later). Since extensive melting may have important consequences, such as differentiation, gas release, and volcanic activity, the effect of 26Al should be included in future studies of satellite interiors. PMID:11538079

  13. Nano-Pervaporation Membrane with Heat Exchanger Generates Medical-Grade Water

    NASA Technical Reports Server (NTRS)

    Tsai, Chung-Yi; Alexander, Jerry

    2009-01-01

    A nanoporous membrane is used for the pervaporation process in which potable water is maintained, at atmospheric pressure, on the feed side of the membrane. The water enters the non-pervaporation (NPV) membrane device where it is separated into two streams -- retentate water and permeated water. The permeated pure water is removed by applying low vapor pressure on the permeate side to create water vapor before condensation. This permeated water vapor is subsequently condensed by coming in contact with the cool surface of a heat exchanger with heat being recovered through transfer to the feed water stream.

  14. Application of the Reverberation-Ray Matrix to the Non-Fourier Heat Conduction in Functionally Graded Materials

    NASA Astrophysics Data System (ADS)

    Zhou, Feng-xi

    2016-02-01

    The method of the reverberation-ray matrix has been developed and successfully applied to analyse the wave propagation in a multibranched framed structure or in a layered medium. However, the method is confined to the case of mechanical loads applied at the medium until now. This paper aims to extend the formulation of the reverberation-ray matrix to cases of thermal propagation and diffusion. The thermal response in functionally graded materials (FGM) with the non-Fourier heat conduction model is analysed. In the present work, it is assumed that the material properties of an FG plate vary only in the thickness direction by following the power law function. The effect of non-Fourier and material inhomogeneity in the plate subjected to a periodic thermal disturbance is investigated. The present approach is validated by comparing it with the solutions obtained by other methods.

  15. Do Different Colors Absorb Heat Better? Grades PreK-2.

    ERIC Educational Resources Information Center

    Rushton, Erik; Ryan, Emily; Swift, Charles

    In this activity, students test whether the color of a material affects how much heat it absorbs. An ice cube is placed in a box made of colored paper (one box per color; white, yellow, red, and black) which is then placed in the sun. Students predict which color will melt the ice cube first and record the order and time required for the ice cubes…

  16. Hot-electron production and suprathermal heat flux scaling with laser intensity from the two-plasmon-decay instability

    NASA Astrophysics Data System (ADS)

    Vu, H. X.; DuBois, D. F.; Myatt, J. F.; Russell, D. A.

    2012-10-01

    The fully kinetic reduced-description particle-in-cell (RPIC) method has been applied to simulations of two-plasmon-decay (TPD) instability, driven by crossed laser beams, in an inhomogeneous plasma for parameters consistent with recent direct-drive experiments related to laser-driven inertial fusion. The nonlinear saturated state is characterized by very spiky electric fields, with Langmuir cavitation occurring preferentially inside density channels produced by the ponderomotive beating of the crossed laser beams and the primary TPD Langmuir waves (LWs). The heated electron distribution function is, in all cases, bi-Maxwellian, with instantaneous hot-electron temperatures in the range 60-100 keV. The net hot-electron energy flux out of the system is a small fraction (˜1% to 2%) of the input laser intensity in these simulations. Scalings of the hot-electron temperature and suprathermal heat flux as functions of the laser intensity are obtained numerically from RPIC simulations. These simulations lead to the preliminary conclusion that Langmuir cavitation and collapse provide dissipation by producing suprathermal electrons, which stabilize the system in saturation and drive the LW spectrum to the small dissipation scales at the Landau cutoff. The Langmuir turbulence originates at an electron density 0.241× the laser's critical density, where the crossed laser beams excite a "triad" mode—a common forward LW plus a pair of backward LWs. Remnants of this "triad" evolve in k-space and dominate the time-averaged energy spectrum. At times exceeding 10 ps, the excited Langmuir turbulence spreads toward lower densities. Comparisons of RPIC simulations with the extended Zakharov model are presented in appropriate regimes, and the necessary requirements for the validity of a quasi-linear Zakharov model (where the spatially averaged electron-velocity distribution is evolved) are verified by RPIC simulation results.

  17. Hot-electron production and suprathermal heat flux scaling with laser intensity from the two-plasmon-decay instability

    SciTech Connect

    Vu, H. X.; DuBois, D. F.; Myatt, J. F.; Russell, D. A.

    2012-10-15

    The fully kinetic reduced-description particle-in-cell (RPIC) method has been applied to simulations of two-plasmon-decay (TPD) instability, driven by crossed laser beams, in an inhomogeneous plasma for parameters consistent with recent direct-drive experiments related to laser-driven inertial fusion. The nonlinear saturated state is characterized by very spiky electric fields, with Langmuir cavitation occurring preferentially inside density channels produced by the ponderomotive beating of the crossed laser beams and the primary TPD Langmuir waves (LWs). The heated electron distribution function is, in all cases, bi-Maxwellian, with instantaneous hot-electron temperatures in the range 60-100 keV. The net hot-electron energy flux out of the system is a small fraction ({approx}1% to 2%) of the input laser intensity in these simulations. Scalings of the hot-electron temperature and suprathermal heat flux as functions of the laser intensity are obtained numerically from RPIC simulations. These simulations lead to the preliminary conclusion that Langmuir cavitation and collapse provide dissipation by producing suprathermal electrons, which stabilize the system in saturation and drive the LW spectrum to the small dissipation scales at the Landau cutoff. The Langmuir turbulence originates at an electron density 0.241 Multiplication-Sign the laser's critical density, where the crossed laser beams excite a 'triad' mode-a common forward LW plus a pair of backward LWs. Remnants of this 'triad' evolve in k-space and dominate the time-averaged energy spectrum. At times exceeding 10 ps, the excited Langmuir turbulence spreads toward lower densities. Comparisons of RPIC simulations with the extended Zakharov model are presented in appropriate regimes, and the necessary requirements for the validity of a quasi-linear Zakharov model (where the spatially averaged electron-velocity distribution is evolved) are verified by RPIC simulation results.

  18. Simulation of decay heat removal by natural convection in a pool type fast reactor model-ramona-with coupled 1D/2D thermal hydraulic code system

    SciTech Connect

    Kasinathan, N.; Rajakumar, A.; Vaidyanathan, G.; Chetal, S.C.

    1995-09-01

    Post shutdown decay heat removal is an important safety requirement in any nuclear system. In order to improve the reliability of this function, Liquid metal (sodium) cooled fast breeder reactors (LMFBR) are equipped with redundant hot pool dipped immersion coolers connected to natural draught air cooled heat exchangers through intermediate sodium circuits. During decay heat removal, flow through the core, immersion cooler primary side and in the intermediate sodium circuits are also through natural convection. In order to establish the viability and validate computer codes used in making predictions, a 1:20 scale experimental model called RAMONA with water as coolant has been built and experimental simulation of decay heat removal situation has been performed at KfK Karlsruhe. Results of two such experiments have been compiled and published as benchmarks. This paper brings out the results of the numerical simulation of one of the benchmark case through a 1D/2D coupled code system, DHDYN-1D/THYC-2D and the salient features of the comparisons. Brief description of the formulations of the codes are also included.

  19. Phase coherence of parametric-decay modes during high-harmonic fast-wave heating in the National Spherical Torus Experiment

    NASA Astrophysics Data System (ADS)

    Carlsson, J. A.; Wilson, J. R.; Hosea, J. C.; Greenough, N. L.; Perkins, R. J.

    2016-06-01

    Third-order spectral analysis, in particular, the auto bicoherence, was applied to probe signals from high-harmonic fast-wave heating experiments in the National Spherical Torus Experiment. Strong evidence was found for parametric decay of the 30 MHz radio-frequency (RF) pump wave, with a low-frequency daughter wave at 2.7 MHz, the local majority-ion cyclotron frequency. The primary decay modes have auto bicoherence values around 0.85, very close to the theoretical value of one, which corresponds to total phase coherence with the pump wave. The threshold RF pump power for onset of parametric decay was found to be between 200 kW and 400 kW.

  20. Modeling of combustion of low grade lignites in fluidized beds with heat extraction

    SciTech Connect

    Mancuhan, E.; Oezyl, E.

    1999-07-01

    A computerized model was developed for any low rank coal with a known particle size distribution and mass fraction. When the coal is fed into the bed, the volatile matter is assumed to be released instantaneously and a new particle size distribution is achieved within the bed. The effect of elutriation and chemical reactions are also taken into account. The model developed investigates the effect of excess air on elutriation, particle size distribution of the semi-coke, and the mass fraction values within the bed at steady state conditions. The excess air ranged from 1 to 1.48. The model also takes into account the effect of coal type on the bed temperature. As is already known, temperature may vary significantly from type to type in the low quality coal range, much more than in the high quality coal types. The results of the model simulation studies are compared with a limited amount of experimental work available for Turkish lignites. The agreement between the model prediction and the experimental data is reasonably good. Closer to the distributor plate, the bed temperature prediction of the model is low, but agreement improves as the active bed surface is reached. The results obtained from the model are presented for feed air temperatures of 300, 400, and 500 K for Seyitoemer lignite. If 60% of the desired heat is extracted from the active bed, the optimum results can be obtained. Under optimum conditions, 70% of the volatile matter is burned within the active bed and the remainder of the freeboard.

  1. Nuclide Importance to Criticality Safety, Decay Heating, and Source Terms Related to Transport and Interim Storage of High-Burnup LWR Fuel

    SciTech Connect

    Gauld, I. C.; Ryman, J. C.

    2000-12-11

    This report investigates trends in the radiological decay properties and changes in relative nuclide importance associated with increasing enrichments and burnup for spent LWR fuel as they affect the areas of criticality safety, thermal analysis (decay heat), and shielding analysis of spent fuel transport and storage casks. To facilitate identifying the changes in the spent fuel compositions that most directly impact these application areas, the dominant nuclides in each area have been identified and ranked by importance. The importance is investigated as a function of increasing burnup to assist in identifying the key changes in spent fuel characteristics between conventional- and extended-burnup regimes. Studies involving both pressurized water-reactor (PWR) fuel assemblies and boiling-water-reactor (BWR) assemblies are included. This study is seen to be a necessary first step in identifying the high-burnup spent fuel characteristics that may adversely affect the accuracy of current computational methods and data, assess the potential impact on previous guidance on isotopic source terms and decay-heat values, and thus help identify areas for methods and data improvement. Finally, several recommendations on the direction of possible future code validation efforts for high-burnup spent fuel predictions are presented.

  2. Creep Deformation, Rupture Analysis, Heat Treatment and Residual Stress Measurement of Monolithic and Welded Grade 91 Steel for Power Plant Components

    NASA Astrophysics Data System (ADS)

    Shrestha, Triratna

    Modified 9Cr-1 Mo (Grade 91) steel is currently considered as a candidate material for reactor pressure vessels (RPVs) and reactor internals for the Very High Temperature Reactor (VHTR), and in fossil-fuel fired power plants at higher temperatures and stresses. The tensile creep behavior of Grade 91 steel was studied in the temperature range of 600°C to 750°C and stresses between 35 MPa and 350 MPa. Heat treatment of Grade 91 steel was studied by normalizing and tempering the steel at various temperatures and times. Moreover, Thermo-Ca1c(TM) calculation was used to predict the precipitate stability and their evolution, and construct carbon isopleths of Grade 91 steel. Residual stress distribution across gas tungsten arc welds (GTAW) in Grade 91 steel was measured by the time-of-flight neutron diffraction using the Spectrometer for Materials Research at Temperature and Stress (SMARTS) diffractometer at Lujan Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, NM, USA. Analysis of creep results yielded stress exponents of ˜9-11 in the higher stress regime and ˜1 in the lower stress regime. The creep behavior of Grade 91 steel was described by the modified Bird-Mukherjee-Dorn relation. The rate-controlling creep deformation mechanism in the high stress regime was identified as the edge dislocation climb with a stress exponent of n = 5. On the other hand, the deformation mechanism in the Newtonian viscous creep regime (n = 1) was identified as the Nabarro-Herring creep. Creep rupture data were analyzed in terms of Monkman-Grant relation and Larson-Miller parameter. Creep damage tolerance factor and stress exponent were used to identify the cause of creep damage. The fracture surface morphology of the ruptured specimens was studied by scanning electron microscopy to elucidate the failure mechanisms. Fracture mechanism map for Grade 91 steel was developed based on the available material parameters and experimental observations. The microstructural

  3. Influence of frequency, grade, moisture and temperature on Green River oil shale dielectric properties and electromagnetic heating processes

    SciTech Connect

    Hakala, J. Alexandra; Stanchina, William; Soong, Yee; Hedges, Sheila

    2011-01-01

    Development of in situ electromagnetic (EM) retorting technologies and design of specific EM well logging tools requires an understanding of various process parameters (applied frequency, mineral phases present, water content, organic content and temperature) on oil shale dielectric properties. In this literature review on oil shale dielectric properties, we found that at low temperatures (<200° C) and constant oil shale grade, both the relative dielectric constant (ε') and imaginary permittivity (ε'') decrease with increased frequency and remain constant at higher frequencies. At low temperature and constant frequency, ε' decreases or remains constant with oil shale grade, while ε'' increases or shows no trend with oil shale grade. At higher temperatures (>200º C) and constant frequency, epsilon' generally increases with temperature regardless of grade while ε'' fluctuates. At these temperatures, maximum values for both ε' and ε'' differ based upon oil shale grade. Formation fluids, mineral-bound water, and oil shale varve geometry also affect measured dielectric properties. This review presents and synthesizes prior work on the influence of applied frequency, oil shale grade, water, and temperature on the dielectric properties of oil shales that can aid in the future development of frequency- and temperature-specific in situ retorting technologies and oil shale grade assay tools.

  4. 7 CFR 51.898 - Decay.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Decay. 51.898 Section 51.898 Agriculture Regulations... Standards for Grades of Table Grapes (European or Vinifera Type) 1 Definitions § 51.898 Decay. Decay means.... Slight surface development of green mold (Cladosporium) shall not be considered decay....

  5. Functionally Graded High-Alloy CrMnNi TRIP Steel Produced by Local Heat Treatment Using High-Energy Electron Beam

    NASA Astrophysics Data System (ADS)

    Heinze, D.; Buchwalder, A.; Jung, A.; Weidner, A.; Segel, C.; Müller, A.; Zenker, R.; Biermann, H.

    2016-01-01

    Cold-rolled, high-alloy CrMnNi TRIP steel was heat treated by electron beam (EB) treatment. After cold rolling to a deformation degree of 70 pct, the microstructure was mainly martensitic with residual austenite. The aim of the subsequent EB treatment was to improve mechanical properties regarding strength and ductility by grain refinement. The process is influenced by EB-specific parameters, resulting in different temperature-time regimes due to different heating and cooling rates. Grain size gradients over the cross section could not be completely suppressed, but minimized. Investigations included optical microscopy, scanning electron microscopy, hardness measurements, quasi static tensile tests, digital image correlation, and thermography for functionally graded tensile specimens. The local heat treatment was used to set specific tailored properties.

  6. Parametric performance of circumferentially grooved heat pipes with homogeneous and graded-porosity slab wicks at cryogenic temperatures. [methane and ethane working fluids

    NASA Technical Reports Server (NTRS)

    Groll, M.; Pittman, R. B.; Eninger, J. E.

    1976-01-01

    A recently developed, potentially high-performance nonarterial wick was extensively tested. This slab wick has an axially varying porosity which can be tailored to match the local stress imposed on the wick. The purpose of the tests was to establish the usefulness of the graded-porosity slab wick at cryogenic temperatures between 110 and 260 K, with methane and ethane as working fluids. For comparison, a homogeneous (i.e., uniform porosity) slab wick was also tested. The tests included: maximum heat pipe performance as a function of fluid inventory, maximum performance as a function of operating temperature, maximum performance as a function of evaporator elevation, and influence of slab wick orientation on performance. The experimental data were compared with theoretical predictions obtained with the GRADE computer program.

  7. Reply to the comments on: ''Series solution of hydromagnetic flow and heat transfer with Hall effect in a second grade fluid over a stretching sheet''

    NASA Astrophysics Data System (ADS)

    Zaman, Haider; Ayub, Muhammad

    2010-06-01

    In this reply to comment on ”Series solution of hydromagnetic flow and heat transfer with Hall effect in a second grade fluid over a stretching sheet” by R. A. Van Gorder and K. Vajravelu manuscript [R. A. Van Gorder, K. Vajravelu, Cent. Eur. J. Phys., DOI:10. 2478/s11534-009-0145-2], we once again claim that the governing similarity equations of Vajravelu and Roper [K. Vajravelu, T. Roper, Int. J. Nonlin. Mech. 34, 1031 (1999)] are incorrect and our claim in [M. Ayub, H. Zaman, M. Ahmad, Cent. Eur. J. Phys. 8, 135 (2010)] is true. For the literature providing justification regarding this issue is discussed in detail.

  8. Reply to the comments on: "Series solution of hydromagnetic flow and heat transfer with Hall effect in a second grade fluid over a stretching sheet"

    NASA Astrophysics Data System (ADS)

    Zaman, Haider; Ayub, Muhammad

    2010-06-01

    In this reply to comment on "Series solution of hydromagnetic flow and heat transfer with Hall effect in a second grade fluid over a stretching sheet" by R. A. Van Gorder and K. Vajravelu manuscript [R. A. Van Gorder, K. Vajravelu, Cent. Eur. J. Phys., DOI:10. 2478/s11534-009-0145-2], we once again claim that the governing similarity equations of Vajravelu and Roper [K. Vajravelu, T. Roper, Int. J. Nonlin. Mech. 34, 1031 (1999)] are incorrect and our claim in [M. Ayub, H. Zaman, M. Ahmad, Cent. Eur. J. Phys. 8, 135 (2010)] is true. For the literature providing justification regarding this issue is discussed in detail.

  9. Heat. A Teacher's Manual for General Level Program Development, Grade 9. Science and Society Teaching Units. Informal Series 49.

    ERIC Educational Resources Information Center

    Roberts, Douglas A.; And Others

    This teacher's manual is one of a series designed to support "general level" program development for intermediate/junior high school science, emphasizing the relationship between science and society. The main body of the manual deals with teaching about heat in the context of home heating systems. In addition, a brief treatment of the particle…

  10. Effect of Post-Weld Heat Treatment on Creep Rupture Properties of Grade 91 Steel Heavy Section Welds

    SciTech Connect

    Li, Leijun

    2012-11-02

    This project will conduct a systematic metallurgical study on the effect of post-weld heat treatment (PWHT) on the creep rupture properties of P91 heavy section welds. The objective is to develop a technical guide for selecting PWHT parameters, and to predict expected creep-rupture life based on the selection of heat treatment parameters. The project consists of four interdependent tasks: Experimentally and numerically characterize the temperature fields of typical post-weld heat treatment procedures for various weld and joint configurations to be used in Gen IV systems. Characterize the microstructure of various regions, including the weld fusion zone, coarse-grain heat-affected zone, and fine-grain heat affected zone, in the welds that underwent the various welding and PWHT thermal histories. Conduct creep and creep-rupture testing of coupons extracted from actual and physically simulated welds. Establish the relationship among PWHT parameters, thermal histories, microstructure, creep, and creep-rupture properties.

  11. An analysis of loss of decay heat removal trends (1989-1994): Outage risk assessment and management (ORAM) technology. Final report

    SciTech Connect

    Wells, J.

    1995-12-01

    There have been many actions taken by the US nuclear industry to improve reactor safety during shutdown conditions. The purpose of this analysis is to determine if the industry initiatives have been effective at reducing the frequency and severity of reactor coolant system loss of inventory and decay heat removal (DHR) incidents during shutdown, and to determine if there are additional insights based on this analysis that should be shared with the industry to continue to improve performance. Operating experience information from 1989 through 1994 was compiled and analyzed to determine the effectiveness of industry initiatives and to provide additional insights. The results of this analysis show there has been a measurable improvement in the number of incidents, the average severity of incidents, and the frequency of significant incidents. In addition, improvement is noted in the frequency and/or severity of previously identified problem areas. This indicates that industry initiatives have been effective at reducing the frequency of incidents during shutdown conditions.

  12. Thermal-hydraulic simulation of natural convection decay heat removal in the High Flux Isotope Reactor using RELAP5 and TEMPEST: Part 1, Models and simulation results

    SciTech Connect

    Morris, D.G.; Wendel, M.W.; Chen, N.C.J.; Ruggles, A.E.; Cook, D.H.

    1989-01-01

    A study was conducted to examine decay heat removal requirements in the High Flux Isotope Reactor (HFIR) following shutdown from 85 MW. The objective of the study was to determine when forced flow through the core could be terminated without causing the fuel to melt. This question is particularly relevant when a station blackout caused by an external event is considered. Analysis of natural circulation in the core, vessel upper plenum, and reactor pool indicates that 12 h of forced flow will permit a safe shutdown with some margin. However, uncertainties in the analysis preclude conclusive proof that 12 h is sufficient. As a result of the study, two seismically qualified diesel generators were installed in HFIR. 9 refs., 4 figs.

  13. Similarity solution to three dimensional boundary layer flow of second grade nanofluid past a stretching surface with thermal radiation and heat source/sink

    SciTech Connect

    Hayat, T.; Muhammad, Taseer; Shehzad, S. A.; Alsaedi, A.

    2015-01-15

    Development of human society greatly depends upon solar energy. Heat, electricity and water from nature can be obtained through solar power. Sustainable energy generation at present is a critical issue in human society development. Solar energy is regarded one of the best sources of renewable energy. Hence the purpose of present study is to construct a model for radiative effects in three-dimensional of nanofluid. Flow of second grade fluid by an exponentially stretching surface is considered. Thermophoresis and Brownian motion effects are taken into account in presence of heat source/sink and chemical reaction. Results are derived for the dimensionless velocities, temperature and concentration. Graphs are plotted to examine the impacts of physical parameters on the temperature and concentration. Numerical computations are presented to examine the values of skin-friction coefficients, Nusselt and Sherwood numbers. It is observed that the values of skin-friction coefficients are more for larger values of second grade parameter. Moreover the radiative effects on the temperature and concentration are quite reverse.

  14. ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS: Apparently Negative Electric Polarization in Shaped Graded Dielectric Materials

    NASA Astrophysics Data System (ADS)

    Fan, Chun-Zhen; Gao, Yin-Hao; Gao, Yong; Huang, Ji-Ping

    2010-05-01

    By using a first-principles approach, we investigate the pathway of electric displacement fields in shaped graded dielectric materials existing in the form of cloaks with various shapes. We reveal a type of apparently negative electric polarization (ANEP), which is due to a symmetric oscillation of the paired electric permittivities, satisfying a sum rule. The ANEP does not occur for a spherical cloak, but appears up to maximum as a/b (the ratio between the long and short principal axis of the spheroidal cloak) is about 5/2, and eventually disappears as a/b becomes large enough corresponding to a rod-like shape. Further, the cloaking efficiency is calculated for different geometrical shapes and demonstrated to closely relate to the ANEP. The possibility of experiments is discussed. This work has relevance to dielectric shielding based on shaped graded dielectric materials.

  15. Measurement Accuracy of Heart Rate and Respiratory Rate during Graded Exercise and Sustained Exercise in the Heat Using the Zephyr BioHarness™

    PubMed Central

    Kim, J.-H.; Roberge, R.; Powell, J. B.; Shafer, A. B.; Williams, W. Jon

    2015-01-01

    The Zephyr BioHarness™ was tested to determine the accuracy of heart rate (HR) and respiratory rate (RR) measurements during 2 exercise protocols in conjunction with either a laboratory metabolic cart (Vmax) or a previously validated portable metabolic system (K4b2). In one protocol, HR and RR were measured using the BioHarness and Vmax during a graded exercise up to V̇O2max (n = 12). In another protocol, HR and RR were measured using the BH and K4b2 during sustained exercise (30 % and 50 % V̇O2max for 20 min each) in a hot environment (30°C, 50 % relative humidity) (n = 6). During the graded exercise, HR but not RR, obtained from the BioHarness was higher compared to the Vmax at baseline and 30 % V̇O2max (p < 0.05), but showed no significant difference at other stages with high correlation coefficients for both HR (r = 0.87–0.96) and RR (r = 0.90–0.99 above 30 % V̇O2max). During the exercise in the heat, there were no significant differences between the BioHarness and K4b2 system. Correlation coefficients between the methods were low for HR but moderately to highly correlated (0.49–0.99) for RR. In conclusion, the BioHarness is comparable to Vmax and K4b2 over a wide range of V̇O2 during graded exercise and sustained exercise in the heat. PMID:23175181

  16. Hybrid Pressure Retarded Osmosis-Membrane Distillation System for Power Generation from Low-Grade Heat: Thermodynamic Analysis and Energy Efficiency

    SciTech Connect

    Lin, SH; Yip, NY; Cath, TY; Osuji, CO; Elimelech, M

    2014-05-06

    We present a novel hybrid membrane system that operates as a heat engine capable of utilizing low-grade thermal energy, which is not readily recoverable with existing technologies. The closed-loop system combines membrane distillation (MD), which generates concentrated and pure water streams by thermal separation, and pressure retarded osmosis (PRO), which converts the energy of mixing to electricity by a hydro-turbine. The PRO-MD system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages for heat source temperatures ranging from 40 to 80 degrees C and working concentrations of 1.0, 2.0, and 4.0 mol/kg NaCl. The factors controlling the energy efficiency of the heat engine were evaluated for both limited and unlimited mass and heat transfer kinetics in the thermal separation stage. In both cases, the relative flow rate between the MD permeate (distillate) and feed streams is identified as an important operation parameter. There is an optimal relative flow rate that maximizes the overall energy efficiency of the PRO-MD system for given working temperatures and concentration. In the case of unlimited mass and heat transfer kinetics, the energy efficiency of the system can be analytically determined based on thermodynamics. Our assessment indicates that the hybrid PRO-MD system can theoretically achieve an energy efficiency of 9.8% (81.6% of the Carnot efficiency) with hot and cold working temperatures of 60 and 20 degrees C, respectively, and a working solution of 1.0 M NaCl. When mass and heat transfer kinetics are limited, conditions that more closely represent actual operations, the practical energy efficiency will be lower than the theoretically achievable efficiency. In such practical operations, utilizing a higher working concentration will yield greater energy efficiency. Overall, our study demonstrates the theoretical viability of the PRO-MD system and identifies the key factors for

  17. 7 CFR 51.2087 - Decay.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Decay. 51.2087 Section 51.2087 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Almonds in the Shell Definitions § 51.2087 Decay. Decay means that part or all...

  18. 7 CFR 51.2962 - Decay.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Decay. 51.2962 Section 51.2962 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Walnuts in the Shell Definitions § 51.2962 Decay. Decay means that any portion...

  19. 7 CFR 51.490 - Decay.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Decay. 51.490 Section 51.490 Agriculture Regulations... Standards for Grades of Cantaloups 1 Definitions § 51.490 Decay. Decay means breakdown, disintegration or fermentation of the flesh or rind of the cantaloup caused by bacteria or fungi; except that dry type...

  20. 7 CFR 51.2962 - Decay.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Decay. 51.2962 Section 51.2962 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Walnuts in the Shell Definitions § 51.2962 Decay. Decay means that any portion...

  1. 7 CFR 51.2120 - Decay.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Decay. 51.2120 Section 51.2120 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Shelled Almonds Definitions § 51.2120 Decay. Decay means that part or all of...

  2. 7 CFR 51.2120 - Decay.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Decay. 51.2120 Section 51.2120 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Shelled Almonds Definitions § 51.2120 Decay. Decay means that part or all of...

  3. 7 CFR 51.2087 - Decay.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Decay. 51.2087 Section 51.2087 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Grades of Almonds in the Shell Definitions § 51.2087 Decay. Decay means that part or all...

  4. 7 CFR 51.490 - Decay.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Decay. 51.490 Section 51.490 Agriculture Regulations... Standards for Grades of Cantaloups 1 Definitions § 51.490 Decay. Decay means breakdown, disintegration or fermentation of the flesh or rind of the cantaloup caused by bacteria or fungi; except that dry type...

  5. Effects of composition and heat treatment on the toughness of ASTM A508 Grade 3 Class 1 material for pressure vessels

    SciTech Connect

    Lin, M.; Hansen, S.S.; Nelson, T.D.; Focht, R.B.

    1997-12-31

    A laboratory study was conducted to evaluate the effects of composition and heat treatment on the toughness of ASTM A508 Grade 3 Class 1 material for pressure vessels. Five steels were vacuum induction melted and cast as ingots in the laboratory. These heats included a base steel representing the specification mid-range analysis, a steel containing higher levels of Si, Ni, and Cr (high-side composition) as compared to the base steel, and three steels derived from the high-side composition by adding Al, Al/N, and Nb, respectively. The ingots were rolled to plate, heat treated, and evaluated. Among these steels, the high-side composition with additions of Al and N displays the best strength/toughness combination. For example, a 75 mm-thick plate of this steel has acceptable strength and a reference nil ductility transition temperature (RT{sub NDT}) of {le} {minus} 29 C after austenitizing at 875 C, air cooling, and tempering at 660 C for up to 20 hours. Upper-nose temper embrittlement (UNTE) occurs in all these steels. This UNTE is attributed to the precipitation of needle-like Mo-rich carbides during tempering, and is significantly reduced by increasing the cooling rate after austenitizing.

  6. Primary-Grade Students' Knowledge and Thinking about the Supply of Utilities (Water, Heat, and Light) to Modern Homes.

    ERIC Educational Resources Information Center

    Brophy, Jere; Alleman, Janet

    2003-01-01

    This interview study gathered information about the prior knowledge and thinking of kindergarten to third- graders regarding the supply of water, heat, and light to modern homes. Findings indicated that students possessed only limited and spotty knowledge about utilities in modern homes. Within general trends, there was evidence of growth in…

  7. Heat Transfer Analysis of MHD Thin Film Flow of an Unsteady Second Grade Fluid Past a Vertical Oscillating Belt

    PubMed Central

    Gul, Taza; Islam, Saeed; Shah, Rehan Ali; Khan, Ilyas; Khalid, Asma; Shafie, Sharidan

    2014-01-01

    This article aims to study the thin film layer flowing on a vertical oscillating belt. The flow is considered to satisfy the constitutive equation of unsteady second grade fluid. The governing equation for velocity and temperature fields with subjected initial and boundary conditions are solved by two analytical techniques namely Adomian Decomposition Method (ADM) and Optimal Homotopy Asymptotic Method (OHAM). The comparisons of ADM and OHAM solutions for velocity and temperature fields are shown numerically and graphically for both the lift and drainage problems. It is found that both these solutions are identical. In order to understand the physical behavior of the embedded parameters such as Stock number, frequency parameter, magnetic parameter, Brinkman number and Prandtl number, the analytical results are plotted graphically and discussed. PMID:25383797

  8. Association between small heat shock protein B11 and the prognostic value of MGMT promoter methylation in patients with high-grade glioma.

    PubMed

    Cheng, Wen; Li, Mingyang; Jiang, Yang; Zhang, Chuanbao; Cai, Jinquan; Wang, Kuanyu; Wu, Anhua

    2016-07-01

    OBJECT This study investigated the role and prognostic value of heat shock proteins (HSPs) in glioma. METHODS Data from 3 large databases of glioma samples (Chinese Glioma Genome Atlas, Repository for Molecular Brain Neoplasia Data, and GSE16011), which contained whole-genome messenger RNA microarray expression data and patients' clinical data, were analyzed. Immunohistochemical analysis was performed to validate protein expression in another set of 50 glioma specimens. RESULTS Of 28 HSPs, 11 were overexpressed in high-grade glioma (HGG) compared with low-grade glioma. A univariate Cox analysis revealed that HSPB11 has significant prognostic value for each glioma grade, which was validated by a Kaplan-Meier survival analysis. HSPB11 expression was associated with poor prognosis and was independently correlated with overall survival (OS) in HGG. This study further explored the combined role of HSPB11 and other molecular markers in HGG, such as isocitrate dehydrogenase 1 (IDH1) mutation and O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation status. HSPB11 expression was able to refine the prognostic value of IDH1 mutation in patients with HGG. However, when combined with MGMT promoter methylation status, among patients with a methylated MGMT promoter, those with lower levels of HSPB11 expression had longer OS and progression-free survival than patients with higher levels of HSPB11 expression or with an unmethylated MGMT promoter. Moreover, within the MGMT promoter methylation group, patients with low levels of HSPB11 expression were more sensitive to combined radiochemotherapy than those with high levels of HSPB11 expression, which may explain why some patients with HGG with a methylated MGMT promoter show tolerance to radiochemotherapy. CONCLUSIONS HSPB11 was identified as a novel prognostic marker in patients with HGG. Together with MGMT promoter methylation status, HSPB11 expression can predict outcome for patients with HGG and identify those who

  9. Application of Response Surface Methodology for Modeling of Postweld Heat Treatment Process in a Pressure Vessel Steel ASTM A516 Grade 70

    PubMed Central

    Peasura, Prachya

    2015-01-01

    This research studied the application of the response surface methodology (RSM) and central composite design (CCD) experiment in mathematical model and optimizes postweld heat treatment (PWHT). The material of study is a pressure vessel steel ASTM A516 grade 70 that is used for gas metal arc welding. PWHT parameters examined in this study included PWHT temperatures and time. The resulting materials were examined using CCD experiment and the RSM to determine the resulting material tensile strength test, observed with optical microscopy and scanning electron microscopy. The experimental results show that using a full quadratic model with the proposed mathematical model is YTS = −285.521 + 15.706X1 + 2.514X2 − 0.004X12 − 0.001X22 − 0.029X1X2. Tensile strength parameters of PWHT were optimized PWHT time of 5.00 hr and PWHT temperature of 645.75°C. The results show that the PWHT time is the dominant mechanism used to modify the tensile strength compared to the PWHT temperatures. This phenomenon could be explained by the fact that pearlite can contribute to higher tensile strength. Pearlite has an intensity, which results in increased material tensile strength. The research described here can be used as material data on PWHT parameters for an ASTM A516 grade 70 weld. PMID:26550602

  10. Application of Response Surface Methodology for Modeling of Postweld Heat Treatment Process in a Pressure Vessel Steel ASTM A516 Grade 70.

    PubMed

    Peasura, Prachya

    2015-01-01

    This research studied the application of the response surface methodology (RSM) and central composite design (CCD) experiment in mathematical model and optimizes postweld heat treatment (PWHT). The material of study is a pressure vessel steel ASTM A516 grade 70 that is used for gas metal arc welding. PWHT parameters examined in this study included PWHT temperatures and time. The resulting materials were examined using CCD experiment and the RSM to determine the resulting material tensile strength test, observed with optical microscopy and scanning electron microscopy. The experimental results show that using a full quadratic model with the proposed mathematical model is YTS = -285.521 + 15.706X1 + 2.514X2 - 0.004X1(2) - 0.001X2(2) - 0.029X1X2. Tensile strength parameters of PWHT were optimized PWHT time of 5.00 hr and PWHT temperature of 645.75°C. The results show that the PWHT time is the dominant mechanism used to modify the tensile strength compared to the PWHT temperatures. This phenomenon could be explained by the fact that pearlite can contribute to higher tensile strength. Pearlite has an intensity, which results in increased material tensile strength. The research described here can be used as material data on PWHT parameters for an ASTM A516 grade 70 weld. PMID:26550602

  11. Hybrid pressure retarded osmosis-membrane distillation system for power generation from low-grade heat: thermodynamic analysis and energy efficiency.

    PubMed

    Lin, Shihong; Yip, Ngai Yin; Cath, Tzahi Y; Osuji, Chinedum O; Elimelech, Menachem

    2014-05-01

    We present a novel hybrid membrane system that operates as a heat engine capable of utilizing low-grade thermal energy, which is not readily recoverable with existing technologies. The closed-loop system combines membrane distillation (MD), which generates concentrated and pure water streams by thermal separation, and pressure retarded osmosis (PRO), which converts the energy of mixing to electricity by a hydro-turbine. The PRO-MD system was modeled by coupling the mass and energy flows between the thermal separation (MD) and power generation (PRO) stages for heat source temperatures ranging from 40 to 80 °C and working concentrations of 1.0, 2.0, and 4.0 mol/kg NaCl. The factors controlling the energy efficiency of the heat engine were evaluated for both limited and unlimited mass and heat transfer kinetics in the thermal separation stage. In both cases, the relative flow rate between the MD permeate (distillate) and feed streams is identified as an important operation parameter. There is an optimal relative flow rate that maximizes the overall energy efficiency of the PRO-MD system for given working temperatures and concentration. In the case of unlimited mass and heat transfer kinetics, the energy efficiency of the system can be analytically determined based on thermodynamics. Our assessment indicates that the hybrid PRO-MD system can theoretically achieve an energy efficiency of 9.8% (81.6% of the Carnot efficiency) with hot and cold working temperatures of 60 and 20 °C, respectively, and a working solution of 1.0 M NaCl. When mass and heat transfer kinetics are limited, conditions that more closely represent actual operations, the practical energy efficiency will be lower than the theoretically achievable efficiency. In such practical operations, utilizing a higher working concentration will yield greater energy efficiency. Overall, our study demonstrates the theoretical viability of the PRO-MD system and identifies the key factors for performance

  12. Mammalian heat shock p70 and histone H4 transcripts, which derive from naturally intronless genes, are immune to nonsense-mediated decay.

    PubMed Central

    Maquat, L E; Li, X

    2001-01-01

    Nonsense-mediated decay (NMD), also called mRNA surveillance, is an evolutionarily conserved pathway that degrades mRNAs that prematurely terminate translation. To date, the pathway in mammalian cells has been shown to depend on the presence of a cis-acting destabilizing element that usually consists of an exon-exon junction generated by the process of pre-mRNA splicing. Whether or not mRNAs that derive from naturally intronless genes, that is, mRNAs not formed by the process of splicing, are also subject to NMD has yet to be investigated. The possibility of NMD is certainly reasonable considering that mRNAs of Saccharomyces cerevisiae are subject to NMD even though most derive from naturally intronless genes. In fact, mRNAs of S. cerevisiae generally harbor a loosely defined splicing-independent destabilizing element that has been proposed to function in NMD analogously to the spliced exon-exon junction of mammalian mRNAs. Here, we demonstrate that nonsense codons introduced into naturally intronless genes encoding mouse heat shock protein 70 or human histone H4 fail to elicit NMD. Failure is most likely because each mRNA lacks a cis-acting destabilizing element, because insertion of a spliceable intron a sufficient distance downstream of a nonsense codon within either gene is sufficient to elicit NMD. PMID:11333024

  13. Runge-Kutta ray tracing technique for solving radiative heat transfer in a two-dimensional graded-index medium

    NASA Astrophysics Data System (ADS)

    Huang, Yong; Shi, Guo-Dong; Zhu, Ke-Yong

    2016-06-01

    This paper adopts the Runge-Kutta ray tracing method to obtain the ray-trajectory numerical solution in a two-dimensional gradient index medium. The emitting, absorbing and scattering processes are simulated by the Monte Carlo method. The temperature field and ray trajectory in the medium are obtained by the three methods, the Runge-Kutta ray tracing method, the ray tracing method with the cell model and the discrete curved ray tracing method with the linear refractive index cell model. Comparing the results of the three methods, it is found that the results by the Monte Carlo Runge-Kutta ray tracing method are of the highest accuracy. To improve the computational speed, the variable step-size Runge-Kutta ray tracing method is proposed, and the maximum relative error between the temperature field in the nonscattering medium by this method and the benchmark solution is less than 0.5%. The results also suggest that the Runge-Kutta ray tracing method would make the radiative transfer solution in the three-dimensional graded index media much easier.

  14. Microstructure and Toughness of Simulated Heat-Affected Zone of Laser Welded Joint for 960 MPa Grade High Strength Steel

    NASA Astrophysics Data System (ADS)

    Meng, Wei; Li, Zhuguo; Jiang, Xiaoxia; Huang, Jian; Wu, Yixiong; Katayama, Seiji

    2014-10-01

    The microstructure and toughness of coarse grain zone (CGZ) and mixed grain zone (MGZ) for laser welded 960 MPa grade high strength steel joints were investigated by thermal simulation with a Gleeble-3500 thermal simulator. The results show that microstructure of the stimulated CGZ mainly consists of uniform interweaved lath martensite, and grain growth is not severe upon increasing the cooling time ( t 8/5). Microstructure of the stimulated MGZ presents strip-like in low peak temperature, and small block martensite is formed on the grain boundary. However, in high peak temperature, the strip-like microstructure disappears and small block martensite presents net-like structure. The lath character for MGZ and CGZ is very obvious under TEM observation, and the average lath thickness of BM, MGZ, and CGZ is 100, 150 and 200 nm, respectively. The impact energy and microhardness of CGZ are higher than MGZ and reduce with increasing the cooling time. The fracture toughness deteriorating drastically for MGZ may be related with the formation of the mixture microstructure, in which the small block martensite is distributed in the shape of a network.

  15. Unsteady stagnation-point flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet.

    PubMed

    Naganthran, Kohilavani; Nazar, Roslinda; Pop, Ioan

    2016-01-01

    In this paper, the unsteady stagnation-point boundary layer flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet has been studied. Similarity transformation is used to transform the system of boundary layer equations which is in the form of partial differential equations into a system of ordinary differential equations. The system of similarity equations is then reduced to a system of first order differential equations and has been solved numerically by using the bvp4c function in Matlab. The numerical solutions for the skin friction coefficient and heat transfer coefficient as well as the velocity and temperature profiles are presented in the forms of tables and graphs. Dual solutions exist for both cases of stretching and shrinking sheet. Stability analysis is performed to determine which solution is stable and valid physically. Results from the stability analysis depict that the first solution (upper branch) is stable and physically realizable, while the second solution (lower branch) is unstable. PMID:27091085

  16. Unsteady stagnation-point flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet

    NASA Astrophysics Data System (ADS)

    Naganthran, Kohilavani; Nazar, Roslinda; Pop, Ioan

    2016-04-01

    In this paper, the unsteady stagnation-point boundary layer flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet has been studied. Similarity transformation is used to transform the system of boundary layer equations which is in the form of partial differential equations into a system of ordinary differential equations. The system of similarity equations is then reduced to a system of first order differential equations and has been solved numerically by using the bvp4c function in Matlab. The numerical solutions for the skin friction coefficient and heat transfer coefficient as well as the velocity and temperature profiles are presented in the forms of tables and graphs. Dual solutions exist for both cases of stretching and shrinking sheet. Stability analysis is performed to determine which solution is stable and valid physically. Results from the stability analysis depict that the first solution (upper branch) is stable and physically realizable, while the second solution (lower branch) is unstable.

  17. Unsteady stagnation-point flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet

    PubMed Central

    Naganthran, Kohilavani; Nazar, Roslinda; Pop, Ioan

    2016-01-01

    In this paper, the unsteady stagnation-point boundary layer flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet has been studied. Similarity transformation is used to transform the system of boundary layer equations which is in the form of partial differential equations into a system of ordinary differential equations. The system of similarity equations is then reduced to a system of first order differential equations and has been solved numerically by using the bvp4c function in Matlab. The numerical solutions for the skin friction coefficient and heat transfer coefficient as well as the velocity and temperature profiles are presented in the forms of tables and graphs. Dual solutions exist for both cases of stretching and shrinking sheet. Stability analysis is performed to determine which solution is stable and valid physically. Results from the stability analysis depict that the first solution (upper branch) is stable and physically realizable, while the second solution (lower branch) is unstable. PMID:27091085

  18. Cytoplasmic and extracellular expression of pharmaceutical-grade mycobacterial 65-kDa heat shock protein in Lactococcus lactis.

    PubMed

    de Azevedo, M S P; Rocha, C S; Electo, N; Pontes, D S; Molfetta, J B; Gonçalves, E D C; Azevedo, V; Silva, C L; Miyoshi, A

    2012-01-01

    Lactic acid bacteria (LAB) are an attractive and safe alternative for the expression of heterologous proteins, as they are nonpathogenic and endotoxin-free organisms. Lactococcus lactis, the LAB model organism, has been extensively employed in the biotechnology field for large-scale production of heterologous proteins, and its use as a "cell factory" has been widely studied. We have been particularly interested in the use of L. lactis for production of heat shock proteins (HSPs), which reportedly play important roles in the initiation of innate and adaptive immune responses. However, this activity has been questioned, as LPS contamination appears to be responsible for most, if not all, immunostimulatory activity of HSPs. In order to study the effect of pure HSPs on the immune system, we constructed recombinant L. lactis strains able to produce and properly address the Mycobacterium leprae 65-kDa HSP (Hsp65) to the cytoplasm or to the extracellular medium, using a xylose-induced expression system. Approximately 7 mg/L recombinant Hsp65 was secreted. Degradation products related to lactococcal HtrA activity were not observed, and the Limulus amebocyte lysate assay demonstrated that the amount of LPS in the recombinant Hsp65 preparations was 10-100 times lower than the permitted levels established by the U.S. Food and Drug Administration. These new L. lactis strains will allow investigation of the effects of M. leprae Hsp65 without the interference of LPS; consequently, they have potential for a variety of biotechnological, medical and therapeutic applications. PMID:22614283

  19. Tooth Decay

    MedlinePlus

    ... decay starts in the outer layer, called the enamel. Without a filling, the decay can get deep into the tooth and its nerves and cause a toothache or abscess. To help prevent cavities Brush your teeth every day with a fluoride toothpaste Clean between ...

  20. Thermal-hydraulic simulation of natural convection decay heat removal in the High Flux Isotope Reactor (HFIR) using RELAP5 and TEMPEST: Part 2, Interpretation and validation of results

    SciTech Connect

    Ruggles, A.E.; Morris, D.G.

    1989-01-01

    The RELAP5/MOD2 code was used to predict the thermal-hydraulic behavior of the HFIR core during decay heat removal through boiling natural circulation. The low system pressure and low mass flux values associated with boiling natural circulation are far from conditions for which RELAP5 is well exercised. Therefore, some simple hand calculations are used herein to establish the physics of the results. The interpretation and validation effort is divided between the time average flow conditions and the time varying flow conditions. The time average flow conditions are evaluated using a lumped parameter model and heat balance. The Martinelli-Nelson correlations are used to model the two-phase pressure drop and void fraction vs flow quality relationship within the core region. Systems of parallel channels are susceptible to both density wave oscillations and pressure drop oscillations. Periodic variations in the mass flux and exit flow quality of individual core channels are predicted by RELAP5. These oscillations are consistent with those observed experimentally and are of the density wave type. The impact of the time varying flow properties on local wall superheat is bounded herein. The conditions necessary for Ledinegg flow excursions are identified. These conditions do not fall within the envelope of decay heat levels relevant to HFIR in boiling natural circulation. 14 refs., 5 figs., 1 tab.

  1. Optimizing VANDLE for Decay Spectroscopy

    NASA Astrophysics Data System (ADS)

    Brewer, N. T.; Taylor, S. Z.; Grzywacz, R.; Madurga, M.; Paulauskas, S. V.; Cizewski, J. A.; Peters, W. A.; Vandle Collaboration

    2013-10-01

    Understanding the decay properties of neutron rich isotopes has well established importance to the path of the r-process and to the total decay heat for reactor physics. Specifically, the half-life, branching ratio and spectra for β-n decay is of particular interest. With that in mind, we have continued attempts to improve upon the Versatile Array of Neutron Detectors at Low Energy (VANDLE) in terms of efficiency and TOF resolution through the use of new and larger scintillators. Details of the new implementation, design and characterization of the array will be shown and compared to previous results.

  2. Low-threshold absolute two-plasmon decay instability in the second harmonic electron cyclotron resonance heating experiments in toroidal devices

    NASA Astrophysics Data System (ADS)

    Popov, A. Yu; Gusakov, E. Z.

    2015-02-01

    The effect of the X-mode parametric decay into two short wavelength upper hybrid (UH) plasmons propagating in opposite directions is analyzed. Due to the huge convective power loss of both the UH plasmons along the inhomogeneity direction, the power threshold of the convective parametric decay instability (PDI), which can be excited in the presence of a monotonous density profile is derived to exceed the gyrotron power range currently available. In the presence of the magnetic island possessing the local density maximum at its O-point the daughter UH plasmons can be trapped in the radial direction that suppresses their energy loss from the decay layer in full and makes the power threshold of the convective two-plasmon PDI drastically (three orders of magnitude) lower than in the previous case. The possibility of the absolute PDI being due to the finite size of the pump beam spot is demonstrated as well. The power threshold of the absolute instability is shown to be more than two orders of magnitude lower than the threshold of the convective instability at the monotonous density profile.

  3. Seal Out Tooth Decay

    MedlinePlus

    ... Topics > Tooth Decay (Caries) > Seal Out Tooth Decay Seal Out Tooth Decay Main Content What are dental ... back teeth decay so easily? Who should get seal​ants? Should sealants be put on baby teeth? ...

  4. 7 CFR 993.601 - More restrictive grade regulation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false More restrictive grade regulation. 993.601 Section 993... PRUNES PRODUCED IN CALIFORNIA Grade Regulations § 993.601 More restrictive grade regulation. (a) Incoming... infestation, and decay shall not exceed fifteen percent (15%), except that the first eight percent (8%) of...

  5. 7 CFR 993.601 - More restrictive grade regulation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false More restrictive grade regulation. 993.601 Section 993... PRUNES PRODUCED IN CALIFORNIA Grade Regulations § 993.601 More restrictive grade regulation. (a) Incoming... infestation, and decay shall not exceed fifteen percent (15%), except that the first eight percent (8%) of...

  6. Rapid heating tensile tests of high-energy-rate-forged 316L stainless steel containing internal helium from radioactive decay of absorbed tritium

    SciTech Connect

    Mosley, W.C.

    1990-01-01

    316L stainless steel is a candidate material for construction of equipment that will be exposed to tritium. This austenitic stainless steel is frequently used in the high-energy-rate-forged (HERF) metallurgical condition to take advantage of increased strength produced by cold work introduced by this process. Proper design of tritium-handling equipment will require an understanding of how helium-3, the product of radioactive decay of tritium, affects mechanical properties. This report describes results of elevated-temperature tensile testing of HERF 316L stainless steel specimens containing helium concentrations of 171 (calculated) atomic parts per million (appm). Results are compared with those reported previously for specimens containing 0 and 94 (measured) appm helium.

  7. Rapid heating tensile tests of high-energy-rate-forged 316L stainless steel containing internal helium from radioactive decay of absorbed tritium

    SciTech Connect

    Mosley, W.C.

    1990-12-31

    316L stainless steel is a candidate material for construction of equipment that will be exposed to tritium. This austenitic stainless steel is frequently used in the high-energy-rate-forged (HERF) metallurgical condition to take advantage of increased strength produced by cold work introduced by this process. Proper design of tritium-handling equipment will require an understanding of how helium-3, the product of radioactive decay of tritium, affects mechanical properties. This report describes results of elevated-temperature tensile testing of HERF 316L stainless steel specimens containing helium concentrations of 171 (calculated) atomic parts per million (appm). Results are compared with those reported previously for specimens containing 0 and 94 (measured) appm helium.

  8. Development of JENDL Decay and Fission Yield Data Libraries

    NASA Astrophysics Data System (ADS)

    Katakura, J.

    2014-04-01

    Decay and fission yield data of fission products have been developed for decay heat calculations to constitute one of the special purpose files of JENDL (Japanese Nuclear Data Library). The decay data in the previous JENDL decay data file have been updated based on the data extracted from ENSDF (Evaluated Nuclear Structure Data File) and those by Total Absorption Gamma-ray Spectroscopy (TAGS) measurements reported recently. Fission yield data have also been updated in order to maintain consistency between the decay and yield data files. Decay heat calculations were performed using the updated decay and yield data, and the results were compared with measured decay heat data to demonstrate their applicability. The uncertainties of the calculated results were obtained by sensitivity analyses. The resulting JENDL calculations and their uncertainty were compared with those from the ENDF and JEFF evaluated files.

  9. Electron capture decay in Jovian planets

    NASA Astrophysics Data System (ADS)

    Zito, R. R.; Schiferl, D.

    1987-12-01

    Following the commonly acknowledged fact that the decay of K-40 substantially contributes to the heating of planetary interiors, an examination is made of the possibility that interior heat in the Jovian planets and stars, where interior pressures may exceed 45 Mbar, may be generated by the pressure-accelerated electron capture decay of a variety of isotopes. The isotopes considered encompass K-40, V-50, Te-123, La-138, Al-26, and Cl-36.

  10. Growth and decay of the Equatorial Atlantic SST mode by means of closed heat budget in a coupled General Circulation Model

    NASA Astrophysics Data System (ADS)

    Polo, Irene; Lazar, Alban; Rodriguez-Fonseca, Belen; Mignot, Juliette

    2015-07-01

    Tropical Atlantic variability is strongly biased in coupled General Circulation Models (GCM). Most of the models present a mean Sea Surface Temperature (SST) bias pattern that resembles the leading mode of inter-annual SST variability. Thus, understanding the causes of the main mode of variability of the system is crucial. A GCM control simulation with the IPSL-CM4 model as part of the CMIP3 experiment has been analyzed. Mixed layer heat budget decomposition has revealed the processes involved in the origin and development of the leading inter-annual variability mode which is defined over the Equatorial Atlantic (hereafter EA mode). In comparison with the observations, it is found a reversal in the anomalous SST evolution of the EA mode: from west equator to southeast in the simulation, while in the observations is the opposite. Nevertheless, despite the biases over the eastern equator and the African coast in boreal summer, the seasonality of the inter-annual variability is well reproduced in the model. The triggering of the EA mode is found to be related to vertical entrainment at the equator as well as to upwelling along South African coast. The damping is related to the air-sea heat fluxes and oceanic horizontal terms. As in the observation, this EA mode exerts an impact on the West African and Brazilian rainfall variability. Therefore, the correct simulation of EA amplitude and time evolution is the key for a correct rainfall prediction over tropical Atlantic. In addition to that, identification of processes which are responsible for the tropical Atlantic biases in GCMs is an important element in order to improve the current global prediction systems.

  11. Beta and gamma decay heat measurements between 0.1s - 50,000s for neturon fission of {sup 235}U, {sup 238}U and {sup 239}Pu. Progress report, June 1, 1992--December 31, 1994

    SciTech Connect

    Schier, W.A.; Couchell, G.P.

    1997-05-01

    In the investigations reported here, a helium-jet/tape-transport system was used for the rapid transfer of fission products to a low-background environment where their aggregate beta and gamma-ray spectra were measured as a function of delay time after neutron induced fission of {sup 235}U, {sup 238}U and {sup 239}Pu. Beta and gamma-ray energy distributions have been deduced for delay times as short as 0.2 s and extending out to 100,000s. Instrumentation development during the initial phase of the project included: (1) assembly and characterization of a NaI(Tl) spectrometer for determining aggregate gamma-ray energy distributions, (2) development and characterization of a beta spectrometer (having excellent gamma-ray rejection) for measuring aggregate beta-particle energy distributions, (3) assembly and characterization of a Compton-suppressed HPGe spectrometer for determining gamma-ray intensities of individual fission products to deduce fission-product yields. Spectral decomposition and analysis codes were developed for deducing energy distributions from measured aggregate beta and gamma spectra. The aggregate measurements in the time interval 0.2 - 20s after fission are of special importance since in this region data from many short-lived nuclei are missing and summation calculations in this region rely on model calculations for a large fraction of their predicted beta and gamma decay heat energy spectra. Comparison with ENDF/B-VI fission product data was performed in parallel with the measurements through a close collaboration with Dr. T. England at LANL, assisted by one of our graduate students. Such aggregate measurements provide tests of the Gross Theory of beta decay used to calculated missing contributions to this data base. Fission-product yields deduced from the HPGe studies will check the accuracy of the semi-empirical Gaussian dispersion model used presently by evaluators in the absence of measured yields.

  12. Semileptonic Decays

    SciTech Connect

    Luth, Vera G.; /SLAC

    2012-10-02

    The following is an overview of the measurements of the CKM matrix elements |V{sub cb}| and |V{sub ub}| that are based on detailed studies of semileptonic B decays by the BABAR and Belle Collaborations and major advances in QCD calculations. In addition, a new and improved measurement of the ratios R(D{sup (*)}) = {Beta}({bar B} {yields} D{sup (*)}{tau}{sup -}{bar {nu}}{sub {tau}})/{Beta}({bar B} {yields} D{sup (*)}{ell}{sup -}{bar {nu}}{sub {ell}}) is presented. Here D{sup (*)} refers to a D or a D* meson and {ell} is either e or {mu}. The results, R(D) = 0.440 {+-} 0.058 {+-} 0.042 and R(D*) = 0.332 {+-} 0.024 {+-} 0.018, exceed the Standard Model expectations by 2.0{sigma} and 2.7{sigma}, respectively. Taken together, they disagree with these expectations at the 3.4{sigma} level. The excess of events cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model.

  13. Dental Caries (Tooth Decay)

    MedlinePlus

    ... Find Data by Topic > Dental Caries (Tooth Decay) Dental Caries (Tooth Decay) Main Content Dental caries (tooth decay) remains the most prevalent chronic ... important source of information on oral health and dental care in the United States since the early ...

  14. Parametric Decay During HHFW on NSTX

    SciTech Connect

    Wilson, J.R.; Bernabei, S.; Biewer, T.; Diem, S.; Hosea, J.; LeBlanc, B.; Phillips, C.K.; Ryan, P.; Swain, D.W.

    2005-09-26

    High Harmonic Fast Wave (HHFW) heating experiments on NSTX have been observed to be accompanied by significant edge ion heating (Ti >> Te). This heating is found to be anisotropic with T perpendicular > T parallel. Simultaneously, coherent oscillations have been detected with an edge Langmuir probe. The oscillations are consistent with parametric decay of the incident fast wave ({omega} > 13{omega}c) into ion Bernstein waves and an unobserved ion-cyclotron quasi-mode. The observation of anisotropic heating is consistent with Bernstein wave damping and the Bernstein waves should completely damp in the plasma periphery as they propagate toward a cyclotron harmonic resonance. The number of daughter waves is found to increase with rf power and to increase as the incident wave's toroidal wavelength increases. The frequencies of the daughter wave are separated by the edge ion cyclotron frequency. Theoretical calculations of the threshold for this decay in uniform plasma indicate an extremely small value of incident power should be required to drive the instability. While such decays are commonly observed at lower harmonics in conventional ICRF heating scenarios they usually do not involve the loss of significant wave power from the pump wave. On NSTX an estimate of the power loss can be found by calculating the minimum power required to support the edge ion heating (presumed to come from the decay Bernstein wave). This calculation indicates at least 20-30% of the incident rf power ends up as decay waves.

  15. Parametric Decay during HHFW on NSTX

    SciTech Connect

    J.R. Wilson; S. Bernabei; T. Biewer; S. Diem; J. Hosea; B. LeBlanc; C.K. Phillips; P. Ryan; D.W. Swain

    2005-05-13

    High Harmonic Fast Wave (HHFW) heating experiments on NSTX have been observed to be accompanied by significant edge ion heating (T{sub i} >> T{sub e}). This heating is found to be anisotropic with T{sub perp} > T{sub par}. Simultaneously, coherent oscillations have been detected with an edge Langmuir probe. The oscillations are consistent with parametric decay of the incident fast wave ({omega} > 13{omega}{sub ci}) into ion Bernstein waves and an unobserved ion-cyclotron quasi-mode. The observation of anisotropic heating is consistent with Bernstein wave damping, and the Bernstein waves should completely damp in the plasma periphery as they propagate toward a cyclotron harmonic resonance. The number of daughter waves is found to increase with rf power, and to increase as the incident wave's toroidal wavelength increases. The frequencies of the daughter wave are separated by the edge ion cyclotron frequency. Theoretical calculations of the threshold for this decay in uniform plasma indicate an extremely small value of incident power should be required to drive the instability. While such decays are commonly observed at lower harmonics in conventional ICRF heating scenarios, they usually do not involve the loss of significant wave power from the pump wave. On NSTX an estimate of the power loss can be found by calculating the minimum power required to support the edge ion heating (presumed to come from the decay Bernstein wave). This calculation indicates at least 20-30% of the incident rf power ends up as decay waves.

  16. Proton decay theory

    SciTech Connect

    Marciano, W.J.

    1983-01-01

    Topics include minimal SU(5) predictions, gauge boson mediated proton decay, uncertainties in tau/sub p/, Higgs scalar effects, proton decay via Higgs scalars, supersymmetric SU(5), dimension 5 operators and proton decay, and Higgs scalars and proton decay. (WHK)

  17. 7 CFR 52.3184 - Grades of dried prunes.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., dirt, foreign material, insect infestation, or decay: Provided, That not more than 1 percent, by weight... flesh damage. 2 damage. 2 Fermentation. Insect infestation.Decay. Fermentation. Scars. Scars. Heat damage. Heat damage. Insect injury. Insect injury. Other means. Other means. Mold. Mold. Dirt....

  18. 7 CFR 52.3184 - Grades of dried prunes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., of the dried prunes may be affected by mold, dirt, foreign material, insect infestation, or decay.... End cracks. Skin or flesh Foreign material. Skin or flesh damage. 2 damage. 2 Fermentation. Insect infestation.Decay. Fermentation. Scars. Scars. Heat damage. Heat damage. Insect injury. Insect injury....

  19. 7 CFR 52.3184 - Grades of dried prunes.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., of the dried prunes may be affected by mold, dirt, foreign material, insect infestation, or decay.... End cracks. Skin or flesh Foreign material. Skin or flesh damage. 2 damage. 2 Fermentation. Insect infestation.Decay. Fermentation. Scars. Scars. Heat damage. Heat damage. Insect injury. Insect injury....

  20. 7 CFR 52.3184 - Grades of dried prunes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., dirt, foreign material, insect infestation, or decay: Provided, That not more than 1 percent, by weight... flesh damage. 2 damage. 2 Fermentation. Insect infestation.Decay. Fermentation. Scars. Scars. Heat damage. Heat damage. Insect injury. Insect injury. Other means. Other means. Mold. Mold. Dirt....

  1. Improving Grading Consistency through Grade Lift Reporting

    ERIC Educational Resources Information Center

    Millet, Ido

    2010-01-01

    We define Grade Lift as the difference between average class grade and average cumulative class GPA. This metric provides an assessment of how lenient the grading was for a given course. In 2006, we started providing faculty members individualized Grade Lift reports reflecting their position relative to an anonymously plotted school-wide…

  2. Simulation Analysis of the NH3-H2O Two-Stage Desorption Type Absorption Refrigerator Driven by Low Grade Waste Heat

    NASA Astrophysics Data System (ADS)

    Takei, Toshitaka; Kimijima, Shinji; Saito, Kiyoshi; Kawai, Sunao

    Recently, from a view point of the environmental protection, NH3-H2O absorption refrigerator attracts attention in the field of the refrigeration and the air conditioning. Since NH3-H2O absorption refrigerators can produce below zero degree products, this type of refrigerators have many usages in the refrigeration. This paper describes the two-stage desorption type absorption refrigerator driven by waste heat of co-generation system. There are two absorption cycles which are operated under the condition of the different pressure and the solution concentration in this absorption refrigerator. It becomes essential to clarify the characteristics of this absorption refrigerator since the operating conditions are changed through out the year in the co-generation system. Particularly, in this paper, we investigate the effects of evaporating temperature of ammonia and cooling water temperature for the performance of this absorption refrigerator by simulation analysis. Through out the research, it is shown that COP can be improved when evaporating temperature is higher or cooling water temperature is lower. In addition to this, it is obtained that the necessary temperature of hot water becomes lower in such condition. As a result, the effectiveness of using this absorption refrigerator under the operating condition of which hot watertemperatureis90∼100[°C] and evaporating temperature is -10∼- 20 [°C] is clarified

  3. Experiments Demonstrate Geothermal Heating Process

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    When engineers design heat-pump-based geothermal heating systems for homes and other buildings, they can use coil loops buried around the perimeter of the structure to gather low-grade heat from the earth. As an alternative approach, they can drill well casings and store the summer's heat deep in the earth, then bring it back in the winter to warm…

  4. Grading More Accurately

    ERIC Educational Resources Information Center

    Rom, Mark Carl

    2011-01-01

    Grades matter. College grading systems, however, are often ad hoc and prone to mistakes. This essay focuses on one factor that contributes to high-quality grading systems: grading accuracy (or "efficiency"). I proceed in several steps. First, I discuss the elements of "efficient" (i.e., accurate) grading. Next, I present analytical results…

  5. Moduli Decays and Gravitinos

    SciTech Connect

    Dine, Michael; Kitano, Ryuichiro; Morisse, Alexander; Shirman, Yuri

    2006-04-21

    One proposed solution of the moduli problem of string cosmology requires that the moduli are quite heavy, their decays reheating the universe to temperatures above the scale of nucleosynthesis. In many of these scenarios, the moduli are approximately supersymmetric; it is then crucial that the decays to gravitinos are helicity suppressed. In this paper, we discuss situations where these decays are, and are not, suppressed. We also comment on a possible gravitino problem from inaton decay.

  6. Baryonic B Decays

    NASA Astrophysics Data System (ADS)

    Chistov, R.

    2016-02-01

    In this talk the decays of B-mesons into baryons are discussed. Large mass of B-meson makes possible the decays of the type B → baryon (+mesons). Experimental observations and measurements of these decays at B-factories Belle and BaBar have stimulate the development of theoretical models in this field. We briefly review the experimental results together with the current theoretical models which describe baryonic B decays.

  7. 7 CFR 810.304 - Grades and grade requirements for canola.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...: Other material: Animal filth 3 3 3 Glass 0 0 0 Unknown foreign substance 1 1 1 U.S. Sample grade Canola... commercially objectionable foreign odor; or (c) Is heating or otherwise of distinctly low quality....

  8. 7 CFR 810.304 - Grades and grade requirements for canola.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...: Other material: Animal filth 3 3 3 Glass 0 0 0 Unknown foreign substance 1 1 1 U.S. Sample grade Canola... commercially objectionable foreign odor; or (c) Is heating or otherwise of distinctly low quality....

  9. 7 CFR 810.304 - Grades and grade requirements for canola.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...: Other material: Animal filth 3 3 3 Glass 0 0 0 Unknown foreign substance 1 1 1 U.S. Sample grade Canola... commercially objectionable foreign odor; or (c) Is heating or otherwise of distinctly low quality....

  10. Plumbing and Heating Curriculum.

    ERIC Educational Resources Information Center

    EASTCONN Regional Educational Services Center, North Windham, CT.

    Theory and experience in the following areas are included in this plumbing curriculum: (1) plumbing fixtures and heating; (2) city water service; (3) fixture roughing; (4) venting; and (5) solar heating systems. The plumbing program manual includes the following sections: (1) general objectives for grades 10, 11, and 12; (2) a list of 33 major…

  11. Asterisk Grade Study Report.

    ERIC Educational Resources Information Center

    Kokorsky, Eileen A.

    A study was conducted at Passaic County Community College (PCCC) to investigate the operation of a grading system which utilized an asterisk (*) grade to indicate progress in a course until a letter grade was assigned. The study sought to determine the persistence of students receiving the "*" grade, the incidence of cases of students receiving…

  12. Grading. Research Brief

    ERIC Educational Resources Information Center

    Walker, Karen

    2006-01-01

    What do grades mean? Is there a commonly understood and acceptable definition for what a grade stands? The current grading system is approximately 100 years old. In the 1700s, students were given feedback but not grades. In 1780, Yale University began using a 4.0 system that is similar to the current system. In the 1830s, Harvard University…

  13. Plus and Minus Grading.

    ERIC Educational Resources Information Center

    Farland, Ronnald; Cepeda, Rita

    The current official policy of the California community colleges on grading prohibits the use of plus and minus symbols to modify a standard letter grade. Plus and minus grades may influence a student's grade point average (GPA) either through statistical effects or psychological effects on teachers and students. At its fall 1985 session, and…

  14. Axions from string decay

    SciTech Connect

    Hagmann, C., LLNL

    1998-07-09

    We have studied numerically the evolution and decay of axion strings. These global defects decay mainly by axion emission and thus contribute to the cosmological axion energy density. The relative importance of this source relative to misalignment production of axions depends on the spectrum. Radiation spectra for various string loop configurations are presented. They support the contention that the string decay contribution is of the same order of magnitude as the contribution from misalignment.

  15. 7 CFR 810.1204 - Grades and grade requirements for rye.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... bushel (pounds) Maximum limits of— Foreign material Foreign matter other than wheat (percent) Total (percent) Damaged kernels Heat damaged (percent) Total (percent) Thin Rye (percent) U.S. No. 1 56.0 1.0 3.0... or garlic odor); or (d) Is heating or otherwise of distinctly low quality. Special Grades and...

  16. Role of radiogenic heat generation in surface heat flow formation

    NASA Astrophysics Data System (ADS)

    Khutorskoi, M. D.; Polyak, B. G.

    2016-03-01

    Heat generation due to decay of long-lived radioactive isotopes is considered in the Earth's crust of the Archean-Proterozoic and Paleozoic provinces of Eurasia and North America. The heat flow that forms in the mantle is calculated as the difference between the heat flow observed at the boundary of the solid Earth and radiogenic heat flow produced in the crust. The heat regime in regions with anomalously high radiogenic heat generation is discussed. The relationship between various heat flow components in the Precambrian and Phanerozoic provinces has been comparatively analyzed, and the role of erosion of the surfaceheat- generating layer has been estimated.

  17. Radioactive Decay - An Analog.

    ERIC Educational Resources Information Center

    McGeachy, Frank

    1988-01-01

    Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

  18. Properties of textile grade ceramic fibers

    NASA Technical Reports Server (NTRS)

    Pudnos, Eric

    1992-01-01

    The availability of textile grade ceramic fibers has sparked great interest for applications in composite reinforcement and high temperature insulation. This paper summarizes the properties of various small diameter textile grade ceramic fibers currently available. Room temperature mechanical and electrical properties of the fibers are discussed for three cases: ambient conditions, after heat aging in argon, and after heat aging in wet air. Dow Corning (R) HPZ Ceramic Fiber, a silicon nitride type fiber, is shown to have improved retention of mechanical and electrical properties above 1200 C.

  19. Hypernuclear Weak Decays

    NASA Astrophysics Data System (ADS)

    Itonaga, K.; Motoba, T.

    The recent theoretical studies of Lambda-hypernuclear weak decaysof the nonmesonic and pi-mesonic ones are developed with the aim to disclose the link between the experimental decay observables and the underlying basic weak decay interactions and the weak decay mechanisms. The expressions of the nonmesonic decay rates Gamma_{nm} and the decay asymmetry parameter alpha_1 of protons from the polarized hypernuclei are presented in the shell model framework. We then introduce the meson theoretical Lambda N -> NN interactions which include the one-meson exchanges, the correlated-2pi exchanges, and the chiral-pair-meson exchanges. The features of meson exchange potentials and their roles on the nonmesonic decays are discussed. With the adoption of the pi + 2pi/rho + 2pi/sigma + omega + K + rhopi/a_1 + sigmapi/a_1 exchange potentials, we have carried out the systematic calculations of the nonmesonic decay observables for light-to-heavy hypernuclei. The present model can account for the available experimental data of the decay rates, Gamma_n/Gamma_p ratios, and the intrinsic asymmetry parameters alpha_Lambda (alpha_Lambda is related to alpha_1) of emitted protons well and consistently within the error bars. The hypernuclear lifetimes are evaluated by converting the total weak decay rates Gamma_{tot} = Gamma_pi + Gamma_{nm} to tau, which exhibit saturation property for the hypernuclear mass A ≥ 30 and agree grossly well with experimental data for the mass range from light to heavy hypernuclei except for the very light ones. Future extensions of the model and the remaining problems are also mentioned. The pi-mesonic weak processes are briefly surveyed, and the calculations and predictions are compared and confirmed by the recent high precision FINUDA pi-mesonic decay data. This shows that the theoretical basis seems to be firmly grounded.

  20. Gleason grading system

    MedlinePlus

    ... medlineplus.gov/ency/patientinstructions/000920.htm Gleason grading system To use the sharing features on this page, ... score of between 5 and 7. Gleason Grading System Sometimes, it can be hard to predict how ...

  1. Axions from wall decay

    SciTech Connect

    Chang, S; Hagmann, C; Sikivie, P

    2001-01-08

    The authors discuss the decay of axion walls bounded by strings and present numerical simulations of the decay process. In these simulations, the decay happens immediately, in a time scale of order the light travel time, and the average energy of the radiated axions is {approx_equal} 7m{sub a} for v{sub a}/m{sub a} {approx_equal} 500. is found to increase approximately linearly with ln(v{sub a}/m{sub a}). Extrapolation of this behavior yields {approx_equal} 60 m{sub a} in axion models of interest.

  2. Modulated curvaton decay

    SciTech Connect

    Assadullahi, Hooshyar; Wands, David; Firouzjahi, Hassan; Namjoo, Mohammad Hossein E-mail: firouz@mail.ipm.ir E-mail: david.wands@port.ac.uk

    2013-03-01

    We study primordial density perturbations generated by the late decay of a curvaton field whose decay rate may be modulated by the local value of another isocurvature field, analogous to models of modulated reheating at the end of inflation. We calculate the primordial density perturbation and its local-type non-Gaussianity using the sudden-decay approximation for the curvaton field, recovering standard curvaton and modulated reheating results as limiting cases. We verify the Suyama-Yamaguchi inequality between bispectrum and trispectrum parameters for the primordial density field generated by multiple field fluctuations, and find conditions for the bound to be saturated.

  3. Combinedatomic-nuclear decay

    NASA Astrophysics Data System (ADS)

    Dzyublik, A. Ya.

    2016-05-01

    We analyzed in details the combined decay of the atomic-nuclear state, which consists of the excited 3/2+ level of 63 153 Eu and K hole, formed in the K capture by 153Gd. This decay proceeds in two stages. First, the nucleus transfers its energy to 2 p electron, which flies into the continuum spectrum, and then returns into 1s hole, emitting γ quantum with the energy equal to the sum of energies of the nuclear and atomic transitions. We estimated the decay probability to be 2.2 × 10-13, that is much less than the recent experimental findings.

  4. Grade-A Perfect

    ERIC Educational Resources Information Center

    Brown, Joseph

    2004-01-01

    Despite the wealth of information available, there is no consensus on best practices for grading. In this article, the author identifies four key philosophical questions that should guide the development of a teacher's grading system and provides tips that can help principals guide teachers in developing a grading system. (Contains 1 figure.)

  5. General Graded Response Model.

    ERIC Educational Resources Information Center

    Samejima, Fumiko

    This paper describes the graded response model. The graded response model represents a family of mathematical models that deal with ordered polytomous categories, such as: (1) letter grading; (2) an attitude survey with "strongly disagree, disagree, agree, and strongly agree" choices; (3) partial credit given in accord with an individual's degree…

  6. [Grading of prostate cancer].

    PubMed

    Kristiansen, G; Roth, W; Helpap, B

    2016-07-01

    The current grading of prostate cancer is based on the classification system of the International Society of Urological Pathology (ISUP) following a consensus conference in Chicago in 2014. The foundations are based on the frequently modified grading system of Gleason. This article presents a brief description of the development to the current ISUP grading system. PMID:27393141

  7. Bias in Grading

    ERIC Educational Resources Information Center

    Malouff, John

    2008-01-01

    Bias in grading can be conscious or unconscious. The author describes different types of bias, such as those based on student attractiveness or performance in prior courses, and a variety of methods of reducing bias, including keeping students anonymous during grading and using detailed criteria for subjective grading.

  8. Redesigning Grading--Districtwide

    ERIC Educational Resources Information Center

    Townsley, Matt

    2014-01-01

    In the first years of his career as a high school math teacher, Matt Townsley was bothered by the fact that his grades penalized students for not learning content quickly. A student could master every standard, but low quiz grades and homework assignments they didn't complete because they didn't understand would lower their final grade,…

  9. Biomass recycling heat technology and energy products

    NASA Astrophysics Data System (ADS)

    Tabakaev, R. B.; Gergelizhiu, P. S.; Kazakov, A. V.; Zavorin, A. S.

    2014-10-01

    Relevance is determined by necessity of utilizing of local low-grade fuels by energy equpment. Most widespread Tomsk oblast (Russian Federation region) low-grade fuels are described and listed. Capability of utilizing is analysed. Mass balances of heat-technology conversion materials and derived products are described. As a result, recycling capability of low-grade fuels in briquette fuel is appraised.

  10. Radiative B Decays

    SciTech Connect

    Bard, D.; /Imperial Coll., London

    2011-11-23

    I discuss recent results in radiative B decays from the Belle and BaBar collaborations. I report new measurements of the decay rate and CP asymmetries in b {yields} s{gamma} and b {yields} d{gamma} decays, and measurements of the photon spectrum in b {yields} s{gamma}. Radiative penguin decays are flavour changing neutral currents which do not occur at tree level in the standard model (SM), but must proceed via one loop or higher order diagrams. These transitions are therefore suppressed in the SM, but offer access to poorlyknown SM parameters and are also a sensitive probe of new physics. In the SM, the rate is dominated by the top quark contribution to the loop, but non-SM particles could also contribute with a size comparable to leading SM contributions. The new physics effects are potentially large which makes them theoretically very interesting, but due to their small branching fractions they are typically experimentally challenging.

  11. RARE KAON DECAYS.

    SciTech Connect

    LITTENBERG, L.

    2005-07-19

    Lepton flavor violation (LFV) experiments have probed sensitivities corresponding to mass scales of well over 100 TeV, making life difficult for models predicting accessible LFV in kaon decay and discouraging new dedicated experiments of this type.

  12. Tooth decay - early childhood

    MedlinePlus

    Bottle mouth; Bottle carries; Baby bottle tooth decay; Early childhood caries (ECC) ... chap 304. Ribeiro NM, Ribeiro MA. Breastfeeding and early childhood caries: a critical review. J Pediatr (Rio J) . ...

  13. Westside Outdoor Teacher's Guide, Grades K-6.

    ERIC Educational Resources Information Center

    Brainard, Lynn; And Others

    This illustrated guide includes activities in Creative Arts, Language Arts, Math, Science, and Social Studies. Activities progress from an animal rhyme quiz for lower grades, to projects for upper level students on soil testing, relative humidity, and solar heat collection. The guide emphasizes activities selected to motivate students to…

  14. A Simple Alternative to Grading

    ERIC Educational Resources Information Center

    Potts, Glenda

    2010-01-01

    In this article, the author investigates whether an alternative grading system (contract grading) would yield the same final grades as traditional grading (letter grading), and whether or not it would be accepted by students. The author states that this study demonstrated that contract grading was widely, and for the most part, enthusiastically…

  15. Decay of metastable topological defects

    SciTech Connect

    Preskill, J. ); Vilenkin, A. Lyman Laboratory of Physics, Harvard University, Cambridge, Massachusetts 02138 )

    1993-03-15

    We systematically analyze the decay of metastable topological defects that arise from the spontaneous breakdown of gauge or global symmetries. Quantum-mechanical tunneling rates are estimated for a variety of decay processes. The decay rate for a global string, vortex, domain wall, or kink is typically suppressed compared to the decay rate for its gauged counterpart. We also discuss the decay of global texture, and of semilocal and electroweak strings.

  16. Long-term strength and allowable stresses of grade 10Kh9MFB and X10CrMoVNb9-1 (T91/P91) chromium heat-resistant steels

    NASA Astrophysics Data System (ADS)

    Skorobogatykh, V. N.; Danyushevskiy, I. A.; Schenkova, I. A.; Prudnikov, D. A.

    2015-04-01

    Currently, grade X10CrMoVNb9-1 (T91, P91) and 10Kh9MFB (10Kh9MFB-Sh) chromium steels are widely applied in equipment manufacturing for thermal power plants in Russia and abroad. Compilation and comparison of tensile, impact, and long-term strength tests results accumulated for many years of investigations of foreign grade X10CrMoVNb9-1, T91, P91, and domestic grade 10Kh9MFB (10Kh9MFB-Sh) steels is carried out. The property identity of metals investigated is established. High strength and plastic properties of steels, from which pipes and other products are made, for operation under creep conditions are confirmed. Design characteristics of long-term strength on the basis of tests with more than one million of hour-samples are determined ( and at temperatures of 500-650°C). The table of recommended allowable stresses for grade 10Kh9MFB, 10Kh9MFB-SH, X10CrMoVNb9-1, T91, and P91 steels is developed. The long-time properties of pipe welded joints of grade 10Kh9MFB+10Kh9MFB, 10Kh9MFB-Sh+10Kh9MFB-Sh, X10CrMoVNb9-1+X10CrMoVNb9-1, P91+P91, T91+T91, 10Kh9MFB (10Kh9MFB-Sh)+X10CrMoVNb9-1(T/P91) steels is researched. The welded joint reduction factor is experimentally determined.

  17. Project ACE Activity Sets. Book I: Grades 3, 4, and 5.

    ERIC Educational Resources Information Center

    Eden City Schools, NC.

    Eleven activity sets suitable for supplementing social studies units in grades 3, 4, and 5 are presented. Each set lists appropriate resources, concepts, general objectives and instructional objectives for each activity within the set. Grade 3 sets are "You Can Help Conserve Our Natural Resources,""Urban Decay and Urban Renewal,""The Use of…

  18. Neutrinoless Double Beta Decay

    NASA Astrophysics Data System (ADS)

    Cremonesi, Oliviero

    2016-05-01

    After more than 3/4 of century from its proposal, Neutrinoless Double Beta Decay (NLDBD) is still missing observation and continues to represent the only practical method for investigating the Dirac/Majorana nature of neutrinos. In case neutrinos would be Majorana particles, NLDBD would provide unique informations on their properties (absolute mass scale and Majorana phases). Boosted by the discovery of neutrino oscillations, a number of experiments with improved sensitivity have been proposed in the past decade. Some of them have recently started operation and others are ready to start. They will push the experimental sensitivity on the decay halflife beyond 1026 year, starting to analyze the region of the inverted mass hierarchy. The status and perspectives of the ongoing experimental effort are reviewed. Uncertainties coming from the calculation othe decay nuclear matrix elements (NME) as well as the recently suggested possibility of a relevant quenching of the axial coupling constant are also discussed.

  19. Decay of superdeformed bands

    SciTech Connect

    Carpenter, M.P.; Khoo, T.L.; Lauritsen, T.

    1995-12-31

    One of the major challenges in the study of superdeformation is to directly connect the large number of superdeformed bands now known to the yrast states. In this way, excitation energies, spins and parities can be assigned to the levels in the second well which is essential to establish the collective and single-particle components of these bands. This paper will review some of the progress which has been made to understand the decay of superdeformed bands using the new arrays including the measurement of the total decay spectrum and the establishment of direct one-step decays from the superdeformed band to the yrast line in {sup 194}Hg. 42 refs., 5 figs.

  20. Suppressed Charmed B Decay

    SciTech Connect

    Snoek, Hella Leonie

    2009-06-02

    This thesis describes the measurement of the branching fractions of the suppressed charmed B0 → D*- a0+ decays and the non-resonant B0 → D*- ηπ+ decays in approximately 230 million Υ(4S) → B$\\bar{B}$ events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B0 → D*- a{sub 0}+ decays show large QCD model dependent uncertainties. Non-factorizing terms, in the naive factorization model, that can be calculated by QCD factorizing models have a large impact on the branching fraction of these decay modes. The predictions of the branching fractions are of the order of 10-6. The measurement of the branching fraction gives more insight into the theoretical models. In general a better understanding of QCD models will be necessary to conduct weak interaction physics at the next level. The presence of CP violation in electroweak interactions allows the differentiation between matter and antimatter in the laws of physics. In the Standard Model, CP violation is incorporated in the CKM matrix that describes the weak interaction between quarks. Relations amongst the CKM matrix elements are used to present the two relevant parameters as the apex of a triangle (Unitarity Triangle) in a complex plane. The over-constraining of the CKM triangle by experimental measurements is an important test of the Standard Model. At this moment no stringent direct measurements of the CKM angle γ, one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle γ can be performed using the decays of neutral B mesons. The B0 → D*- a0+ decay is sensitive to the angle γ and, in comparison to the current decays that are being employed, could significantly

  1. What Is Heat? Inquiry regarding the Science of Heat

    ERIC Educational Resources Information Center

    Rascoe, Barbara

    2010-01-01

    This lab activity uses inquiry to help students define heat. It is generic in that it can be used to introduce a plethora of science content across middle and high school grade levels and across science disciplines that include biology, Earth and space science, and physical science. Even though heat is a universal science phenomenon that is…

  2. Weak decay of hypernuclei

    SciTech Connect

    Grace, R.

    1983-01-01

    The Moby Dick spectrometer (at BNL) in coincidence with a range spectrometer and a TOF neutron detector will be used to study the weak decay modes of /sup 12/C. The Moby Dick spectrometer will be used to reconstruct and tag events in which specific hypernuclear states are formed in the reaction K/sup -/ + /sup 12/C ..-->.. ..pi../sup -/ + /sup 12/C. Subsequent emission of decay products (pions, protons and neutrons) in coincidence with the fast forward pion will be detected in a time and range spectrometer, and a neutron detector.

  3. Search for the decay

    NASA Astrophysics Data System (ADS)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; d'Argent, P.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Birnkraut, A.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Braun, S.; Brett, D.; Britsch, M.; Britton, T.; Brodzicka, J.; Brook, N. H.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Campana, P.; Campora Perez, D.; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carniti, P.; Carson, L.; Carvalho Akiba, K.; Casanova Mohr, R.; Casse, G.; Cassina, L.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Cavallero, G.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chefdeville, M.; Chen, S.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Corvo, M.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Dean, C.-T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Di Ruscio, F.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dreimanis, K.; Dujany, G.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H. M.; Evans, T.; Falabella, A.; Färber, C.; Farinelli, C.; Farley, N.; Farry, S.; Fay, R.; Ferguson, D.; Fernandez Albor, V.; Ferrari, F.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fol, P.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; García Pardiñas, J.; Garofoli, J.; Garra Tico, J.; Garrido, L.; Gascon, D.; Gaspar, C.; Gastaldi, U.; Gauld, R.; Gavardi, L.; Gazzoni, G.; Geraci, A.; Gerick, D.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Gianì, S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gotti, C.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graverini, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Humair, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Karodia, S.; Kelsey, M.; Kenyon, I. R.; Kenzie, M.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Klimaszewski, K.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Likhomanenko, T.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lucchesi, D.; Lucio Martinez, M.; Luo, H.; Lupato, A.; Luppi, E.; Lupton, O.; Machefert, F.; Maciuc, F.; Maev, O.; Malde, S.; Malinin, A.; Manca, G.; Mancinelli, G.; Manning, P.; Mapelli, A.; Maratas, J.; Marchand, J. F.; Marconi, U.; Marin Benito, C.; Marino, P.; Märki, R.; Marks, J.; Martellotti, G.; Martinelli, M.; Martinez Santos, D.; Martinez Vidal, F.; Martins Tostes, D.; Massafferri, A.; Matev, R.; Mathad, A.; Mathe, Z.; Matteuzzi, C.; Matthieu, K.; Mauri, A.; Maurin, B.; Mazurov, A.; McCann, M.; McCarthy, J.; McNab, A.; McNulty, R.; Meadows, B.; Meier, F.; Meissner, M.; Merk, M.; Milanes, D. A.; Minard, M.-N.; Mitzel, D. S.; Molina Rodriguez, J.; Monteil, S.; Morandin, M.; Morawski, P.; Mordà, A.; Morello, M. J.; Moron, J.; Morris, A. B.; Mountain, R.; Muheim, F.; Müller, J.; Müller, K.; Müller, V.; Mussini, M.; Muster, B.; Naik, P.; Nakada, T.; Nandakumar, R.; Nasteva, I.; Needham, M.; Neri, N.; Neubert, S.; Neufeld, N.; Neuner, M.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Niess, V.; Niet, R.; Nikitin, N.; Nikodem, T.; Ninci, D.; Novoselov, A.; O'Hanlon, D. P.; Oblakowska-Mucha, A.; Obraztsov, V.; Ogilvy, S.; Okhrimenko, O.; Oldeman, R.; Onderwater, C. J. G.; Osorio Rodrigues, B.; Otalora Goicochea, J. M.; Otto, A.; Owen, P.; Oyanguren, A.; Palano, A.; Palombo, F.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Pappalardo, L. L.; Parkes, C.; Passaleva, G.; Patel, G. D.; Patel, M.; Patrignani, C.; Pearce, A.; Pellegrino, A.; Penso, G.; Pepe Altarelli, M.; Perazzini, S.; Perret, P.; Pescatore, L.; Petridis, K.; Petrolini, A.; Petruzzo, M.; Picatoste Olloqui, E.; Pietrzyk, B.; Pilař, T.; Pinci, D.; Pistone, A.; Playfer, S.; Plo Casasus, M.; Poikela, T.; Polci, F.; Poluektov, A.; Polyakov, I.; Polycarpo, E.; Popov, A.; Popov, D.; Popovici, B.; Potterat, C.; Price, E.; Price, J. D.; Prisciandaro, J.; Pritchard, A.; Prouve, C.; Pugatch, V.; Puig Navarro, A.; Punzi, G.; Qian, W.; Quagliani, R.; Rachwal, B.; Rademacker, J. H.; Rakotomiaramanana, B.; Rama, M.; Rangel, M. S.; Raniuk, I.; Rauschmayr, N.; Raven, G.; Redi, F.; Reichert, S.; Reid, M. M.; dos Reis, A. C.; Ricciardi, S.; Richards, S.; Rihl, M.; Rinnert, K.; Rives Molina, V.; Robbe, P.; Rodrigues, A. B.; Rodrigues, E.; Rodriguez Lopez, J. A.; Rodriguez Perez, P.; Roiser, S.; Romanovsky, V.; Romero Vidal, A.; Rotondo, M.; Rouvinet, J.; Ruf, T.; Ruiz, H.; Ruiz Valls, P.; Saborido Silva, J. J.; Sagidova, N.; Sail, P.; Saitta, B.; Salustino Guimaraes, V.; Sanchez Mayordomo, C.; Sanmartin Sedes, B.; Santacesaria, R.; Santamarina Rios, C.; Santovetti, E.; Sarti, A.; Satriano, C.; Satta, A.; Saunders, D. M.; Savrina, D.; Schiller, M.; Schindler, H.; Schlupp, M.; Schmelling, M.; Schmelzer, T.; Schmidt, B.; Schneider, O.; Schopper, A.; Schune, M.-H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Semennikov, A.; Sepp, I.; Serra, N.; Serrano, J.; Sestini, L.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, V.; Shires, A.; Silva Coutinho, R.; Simi, G.; Sirendi, M.; Skidmore, N.; Skillicorn, I.; Skwarnicki, T.; Smith, E.; Smith, E.; Smith, J.; Smith, M.; Snoek, H.; Sokoloff, M. D.; Soler, F. J. P.; Soomro, F.; Souza, D.; Souza De Paula, B.; Spaan, B.; Spradlin, P.; Sridharan, S.; Stagni, F.; Stahl, M.; Stahl, S.; Steinkamp, O.; Stenyakin, O.; Sterpka, F.; Stevenson, S.; Stoica, S.; Stone, S.; Storaci, B.; Stracka, S.; Straticiuc, M.; Straumann, U.; Stroili, R.; Sun, L.; Sutcliffe, W.; Swientek, K.; Swientek, S.; Syropoulos, V.; Szczekowski, M.; Szczypka, P.; Szumlak, T.; T'Jampens, S.; Tekampe, T.; Teklishyn, M.; Tellarini, G.; Teubert, F.; Thomas, C.; Thomas, E.; van Tilburg, J.; Tisserand, V.; Tobin, M.; Todd, J.; Tolk, S.; Tomassetti, L.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Trabelsi, K.; Tran, M. T.; Tresch, M.; Trisovic, A.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Ukleja, A.; Ustyuzhanin, A.; Uwer, U.; Vacca, C.; Vagnoni, V.; Valenti, G.; Vallier, A.; Vazquez Gomez, R.; Vazquez Regueiro, P.; Vázquez Sierra, C.; Vecchi, S.; Velthuis, J. J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vieites Diaz, M.; Vilasis-Cardona, X.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voß, C.; de Vries, J. A.; Waldi, R.; Wallace, C.; Wallace, R.; Walsh, J.; Wandernoth, S.; Wang, J.; Ward, D. R.; Watson, N. K.; Websdale, D.; Weiden, A.; Whitehead, M.; Wiedner, D.; Wilkinson, G.; Wilkinson, M.; Williams, M.; Williams, M. P.; Williams, M.; Wilson, F. F.; Wimberley, J.; Wishahi, J.; Wislicki, W.; Witek, M.; Wormser, G.; Wotton, S. A.; Wright, S.; Wyllie, K.; Xie, Y.; Xu, Z.; Yang, Z.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zavertyaev, M.; Zhang, L.; Zhang, Y.; Zhelezov, A.; Zhokhov, A.; Zhong, L.

    2015-08-01

    A search for decays is performed using 3 .0 fb1- of pp collision data recorded by the LHCb experiment during 2011 and 2012. The f 0(980) meson is reconstructed through its decay to the π + π - final state in the mass window 900 MeV /c 2 < m( π + π -) < 1080 MeV /c 2. No significant signal is observed. The first upper limits on the branching fraction of are set at 90 % (95 %) confidence level. [Figure not available: see fulltext.

  4. Decay of relativistic hypernuclei

    SciTech Connect

    Majlingova, Olga

    2008-05-12

    The contribution is focused on the analysis of the hypernuclei decay. Hypernuclei, nuclei composed of nucleons and hyperon, enable us to more precise study baryon-baryon interaction, both weak and strong. Several experiments for study new hypernuclear objects are presently taking data or are planned in several laboratories in Italy, Germany, Russia, Japan and USA. The aim of the contribution is the introduction the catalogue of all possible decays of light hypernuclei (A{<=}12). Created catalogue could be exploited for planning next experiments.

  5. Naturally formed graded junction for organic light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Shao, Yan; Yang, Yang

    2003-09-01

    In this letter, we report naturally-formed graded junctions (NFGJ) for organic light-emitting diodes (OLEDs). These junctions are fabricated using single thermal evaporation boat loaded with uniformly mixed charge transport and light-emitting materials. Upon heating, materials sublimate sequentially according to their vaporizing temperatures forming the graded junction. Two kinds of graded structures, sharp and shallow graded junctions, can be formed based on the thermal properties of the selected materials. The NFGJ OLEDs have shown excellent performance in both brightness and lifetime compared with heterojunction devices.

  6. Heat pipe array heat exchanger

    DOEpatents

    Reimann, Robert C.

    1987-08-25

    A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

  7. Beef grading by ultrasound

    NASA Technical Reports Server (NTRS)

    Gammell, P. M.

    1981-01-01

    Reflections in ultrasonic A-scan signatures of beef carcasses indicate USDA grade. Since reflections from within muscle are determined primarily by fat/muscle interface, richness of signals is direct indication of degree of marbling and quality. Method replaces subjective sight and feel tests by individual graders and is applicable to grade analysis of live cattle.

  8. Grain Grading and Handling.

    ERIC Educational Resources Information Center

    Rendleman, Matt; Legacy, James

    This publication provides an introduction to grain grading and handling for adult students in vocational and technical education programs. Organized in five chapters, the booklet provides a brief overview of the jobs performed at a grain elevator and of the techniques used to grade grain. The first chapter introduces the grain industry and…

  9. Classroom: Efficient Grading

    ERIC Educational Resources Information Center

    Shaw, David D.; Pease, Leonard F., III.

    2014-01-01

    Grading can be accelerated to make time for more effective instruction. This article presents specific time management strategies selected to decrease administrative time required of faculty and teaching assistants, including a multiple answer multiple choice interface for exams, a three-tier grading system for open ended problem solving, and a…

  10. Controlling Grade Inflation

    ERIC Educational Resources Information Center

    Stanoyevitch, Alexander

    2008-01-01

    In this article concerning grade inflation, the author restricts his attention to the college and university level, although many of the tools and ideas developed here should be useful for high schools as well. The author considers the relationships between grades instructors assign and scores they receive on end-of-the semester student…

  11. Are Math Grades Cyclical?

    ERIC Educational Resources Information Center

    Adams, Gerald J.; Dial, Micah

    1998-01-01

    The cyclical nature of mathematics grades was studied for a cohort of elementary school students from a large metropolitan school district in Texas over six years (average cohort size of 8495). The study used an autoregressive integrated moving average (ARIMA) model. Results indicate that grades do exhibit a significant cyclical pattern. (SLD)

  12. [Grading of neuroendocrine tumors].

    PubMed

    Saeger, W; Schnabel, P A; Komminoth, P

    2016-07-01

    The current WHO classification of neuroendocrine tumors (NET) differentiates between typical carcinoids (low grade NET), atypical carcinoids (intermediate grade NET) and small cell and large cell carcinomas (high grade NET) according to the prognosis. Neuroendocrine neoplasms (NEN) of the gastrointestinal tract and the pancreas are graded in an identical way. Together with the TNM system this enables a preoperative estimation of the prognosis in biopsies and fine needle aspirates. Well-differentiated tumors are graded into G1 tumors by the number of mitoses, <2 per 10 high-power fields (HPF) and the Ki-67 (index <3 %) and G2 tumors (2-20 mitoses/10 HPF, Ki-67 3-20 %). Discrepancies between the number of mitoses and the Ki-67 index are not uncommon and in these cases the higher value of the two should be applied. The more differentiated tumors of the G3 type have to be differentiated from undifferentiated carcinomas of the small cell type and large cell type with a much poorer prognosis. Prognosis relevant grading of thyroid cancers is achieved by special subtyping so that the G1-G3 system is not applicable. The rare cancers of the parathyroid gland and of the pituitary gland are not graded. Adrenal tumors also have no grading system. The prognosis is dependent on the Ki-67 index and with some reservations on the established scoring systems. PMID:27379621

  13. Grading Exceptional Learners

    ERIC Educational Resources Information Center

    Jung, Lee Ann; Guskey, Thomas R.

    2010-01-01

    Teachers often grapple with the challenge of giving report card grades to students with learning disabilities and English language learners. The authors offer a five-step model that "offers a fair, accurate, and legal way to adapt the grading process for exceptional learners." The model begins with a high-quality reporting system for all students…

  14. Third Grade Reading Policies

    ERIC Educational Resources Information Center

    Rose, Stephanie

    2012-01-01

    In 2012, 14 states passed legislation geared toward improving 3rd-grade literacy through identification, intervention, and/or retention initiatives. Today, a total of 32 states and the District of Columbia have policies in statute aimed at improving 3rd-grade reading proficiency. The majority of these states require early assessment and…

  15. Making Grading Work.

    ERIC Educational Resources Information Center

    Lotto, Edward; Smith, Bruce

    Two teachers have developed a procedure for grading student compositions that seems fairer to both them and their students. The students are given a choice of which papers they wish to submit for grading, and when they do submit work, the papers are identified by a number only (chosen by the student and indexed in a class card file). Each teacher…

  16. Determining Faculty Grading Variation.

    ERIC Educational Resources Information Center

    Demerjian, Marlene D.

    A study was undertaken at the College of the Canyons, in California, to assess the variation of grades given by mathematics instructors teaching intermediate algebra. A sample was drawn from all instructors who taught Math 070 repeatedly from fall 1990 to fall 1994, resulting in the examination of the grades of at least 200 students from classes…

  17. Grades out, Badges in

    ERIC Educational Resources Information Center

    Young, Jeffrey R.

    2012-01-01

    Grades are broken. Students grub for them, pick classes where good ones come easily, and otherwise hustle to win the highest scores for the least learning. As a result, college grades are inflated to the point of meaninglessness--especially to employers who want to know which diploma-holder is best qualified for their jobs. An alternative is to…

  18. The Grades Game

    ERIC Educational Resources Information Center

    Fleenor, Andy; Lamb, Sarah; Anton, Jennifer; Stinson, Todd; Donen, Tony

    2011-01-01

    It can be quite alarming (and eye-opening) to see exactly how many of the grades students receive are based on their behaviors rather than their learning. Students should be assessed on what they know and can use rather than on their behavior. The reality, unfortunately, is that the opposite is often the case. Grades for students who work hard are…

  19. Are Grades Undermining Motivation?

    ERIC Educational Resources Information Center

    Berliner, David; Casanova, Ursula

    1988-01-01

    A study of fifth and sixth grade public school students in Israel suggests that grades and other norm-referenced methods are less effective than task-involving evaluation methods in enhancing student performance, interest, and motivation. This article consists of two commentaries on the findings, with suggestions for implementing task-involving…

  20. Decay Time of Cathodoluminescence

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2009-01-01

    Simple measurements of the decay time of cathodoluminescence are described. Cathodoluminescence is used in many devices, including computer monitors, oscilloscopes, radar displays and television tubes. The experimental setup is simple and easy to build. Two oscilloscopes, a function generator, and a fast photodiode are needed for the experiments.…

  1. Chiral quirkonium decays

    NASA Astrophysics Data System (ADS)

    Fok, R.; Kribs, Graham D.

    2011-08-01

    We calculate the two-body decay rates of quirkonium states formed from quirks that acquire mass solely through electroweak symmetry breaking. We consider SU(N)ic infracolor with two flavors of quirks transforming under the electroweak group (but not QCD) of the standard model. In one case, the quirks are in a chiral representation of the electroweak group, while in the other case, a vectorlike representation. The differences in the dominant decay channels between “chiral quirkonia” versus “vectorlike quirkonia” are striking. Several chiral quirkonia states can decay into the unique two-body resonance channels WH, ZH, tt¯, tb¯/bt¯, and γH, which never dominate for vectorlike quirkonia. Additionally, the channels WW, WZ, ZZ, and Wγ, are shared among both chiral and vectorlike quirkonia. Resonances of dileptons or light quarks (dijets) can dominate for some vectorlike quirkonia states throughout their mass range, while these modes never dominate for chiral quirkonia unless the decays into pairs of gauge or Higgs bosons are kinematically forbidden.

  2. Chiral Quirkonium Decays

    SciTech Connect

    Fok, R.; Kribs, Graham D.; /Fermilab

    2011-06-01

    We calculate the two-body decay rates of quirkonium states formed from quirks that acquire mass solely through electroweak symmetry breaking. We consider SU(N){sub ic} infracolor with two flavors of quirks transforming under the electroweak group (but not QCD) of the standard model. In one case, the quirks are in a chiral representation of the electroweak group, while in the other case, a vectorlike representation. The differences in the dominant decay channels between 'chiral quirkonia' versus 'vectorlike quirkonia' are striking. Several chiral quirkonia states can decay into the unique two-body resonance channels WH, ZH, t{bar t}, t{bar b}/b{bar t}, and {gamma}H, which never dominate for vectorlike quirkonia. Additionally, the channels WW, WZ, ZZ, and W{gamma}, are shared among both chiral and vectorlike quirkonia. Resonances of dileptons or light quarks (dijets) can dominate for some vectorlike quirkonia states throughout their mass range, while these modes never dominate for chiral quirkonia unless the decays into pairs of gauge or Higgs bosons are kinematically forbidden.

  3. Heat pump apparatus

    DOEpatents

    Nelson, Paul A.; Horowitz, Jeffrey S.

    1983-01-01

    A heat pump apparatus including a compact arrangement of individual tubular reactors containing hydride-dehydride beds in opposite end sections, each pair of beds in each reactor being operable by sequential and coordinated treatment with a plurality of heat transfer fluids in a plurality of processing stages, and first and second valves located adjacent the reactor end sections with rotatable members having multiple ports and associated portions for separating the hydride beds at each of the end sections into groups and for simultaneously directing a plurality of heat transfer fluids to the different groups. As heat is being generated by a group of beds, others are being regenerated so that heat is continuously available for space heating. As each of the processing stages is completed for a hydride bed or group of beds, each valve member is rotated causing the heat transfer fluid for the heat processing stage to be directed to that bed or group of beds. Each of the end sections are arranged to form a closed perimeter and the valve member may be rotated repeatedly about the perimeter to provide a continuous operation. Both valves are driven by a common motor to provide a coordinated treatment of beds in the same reactors. The heat pump apparatus is particularly suitable for the utilization of thermal energy supplied by solar collectors and concentrators but may be used with any source of heat, including a source of low-grade heat.

  4. Anatomy of decays

    NASA Astrophysics Data System (ADS)

    Bel, Lennaert; De Bruyn, Kristof; Fleischer, Robert; Mulder, Mick; Tuning, Niels

    2015-07-01

    The decays B {/d 0} → D {/d -} D {/d +} and B {/s 0} → D {/s -} D {/s +} probe the CP-violating mixing phases ϕ d and ϕ s , respectively. The theoretical uncertainty of the corresponding determinations is limited by contributions from penguin topologies, which can be included with the help of the U-spin symmetry of the strong interaction. We analyse the currently available data for B {/d, s 0} → D {/d, s -} D {/d, s +} decays and those with similar dynamics to constrain the involved non-perturbative parameters. Using further information from semileptonic B {/d 0} → D {/d -} ℓ + ν ℓ decays, we perform a test of the factorisation approximation and take non-factorisable SU(3)-breaking corrections into account. The branching ratios of the B {/d 0} → D {/d -} D {/d +}, B {/s 0} → D {/s -} D {/d +} and B {/s 0} → D {/s -} D {/s +}, B {/d 0} → D {/d -} D {/s +} decays show an interesting pattern which can be accommodated through significantly enhanced exchange and penguin annihilation topologies. This feature is also supported by data for the B {/s 0} → D {/d -} D {/d +} channel. Moreover, there are indications of potentially enhanced penguin contributions in the B {/d 0} → D {/d -} D {/d +} and B {/s 0} → D {/s -} D {/s +} decays, which would make it mandatory to control these effects in the future measurements of ϕ d and ϕ s . We discuss scenarios for high-precision measurements in the era of Belle II and the LHCb upgrade.

  5. Five Obstacles to Grading Reform

    ERIC Educational Resources Information Center

    Guskey, Thomas R.

    2011-01-01

    Educators seeking to reform grading must combat five long-held traditions that stand as formidable obstacles to change: (1) Grades should provide the basis for differentiating students; (2) grade distributions should resemble a bell-shaped curve; (3) grades should be based on students' standing among classmates; (4) poor grades prompt students to…

  6. Paperless Grades and Faculty Development.

    ERIC Educational Resources Information Center

    Hardy, James C.; Jones, Dennis; Turner, Sandy

    2003-01-01

    Provides overview of process of switching from paper-based grade reporting to computer-based grading. Authors found that paperless grading decreased number of errors, made student access more immediate, and reduced costs incurred by purchasing and storing grade-scanning sheets. Authors also argue that direct entry grading encourages faculty to…

  7. Rare Down Quark Decays

    NASA Astrophysics Data System (ADS)

    Tung, Kwong-Kwai Humphrey

    1992-01-01

    The rare decays bto sX are sensitive to strong interaction corrections. The effects can be estimated by a renormalization group technique which requires the evaluation of QCD mixing among effective operators. In the dimensional reduction and the naive dimensional regularization methods, there are discrepancies in evaluating the QCD mixing of the four-quark operators with the bto sgamma and bto s+gluon dipole operators. In this thesis, the problem is investigated by considering the contributions of the epsilon -scalar field and the epsilon -dimensional operators that distinguish between the two methods. The discrepancies are shown to come from the epsilon-dimensional four-quark operators in dimensional reduction and not from the epsilon -scalar field. In the decay bto sl^+l^ -, the intermediate of cc pairs in the charm-penguin diagram can form the resonance states J/psi and psi^'. In the published literature, there is a sign discrepancy in the Breit-Wigner amplitude for the resonance effects. Here, the sign difference is settled by considering the unitarity limit of the amplitude in the Argand diagram. The effects of the resonances are quite substantial on the invariant mass spectrum for this decay. However, they are shown to be negligible on the dilepton energy spectrum below 0.95 GeV. The energy spectrum is, thus, more useful than the invariant mass spectrum for measurements of the top -quark mass. The decays Bto K^*X are well modeled by the quark-level decays bto sX. In the quark model, the hadronization is done using a nonrelativistic wave function. In the decay B to K^*gamma, the large K ^* recoil creates an uncertainty in calculating the branching ratio using the quark model. The problem is explored by considering other meson processes where data exist. The data on the pi form factor and the omegapi^0 transition form factor suggest the necessity to retain relativistic spinor and meson normalizations in the quark -model; however, the data do not resolve the

  8. [Grading of lung cancer].

    PubMed

    Bohle, R M; Schnabel, P A

    2016-07-01

    In comparison with other tumor entities there is no common generally accepted grading system for lung cancer with clearly defined criteria and clinical relevance. In the recent fourth edition of the World Health Organization (WHO) classification from 2015 of tumors of the lungs, pleura, thymus and heart, there is no generally applicable grading for pulmonary adenocarcinomas, squamous cell carcinomas or rarer forms of carcinoma. Since the new IASLC/ATS/ERS classification of adenocarcinomas published in 2011, 5 different subtypes with significantly different prognosis are proposed. This results in an architectural (histologic) grading, which is usually applied to resection specimens. For squamous cell carcinoma the number of different histological subtypes in the new WHO classification was reduced compared to earlier versions but without a common grading system. In recent publications nesting and budding were proposed as the main (histologic) criteria for a grading of squamous cell carcinomas. The grading of neuroendocrine tumors (NET) of the lungs in comparison with NET in other organs is presented in a separate article in this issue. Certain rare tumor types are high grade per definition: small cell, large cell and pleomorphic carcinomas, carcinosarcomas and pulmonary blastomas. In the future it is to be expected that these developments will be further refined, e. g. by adding further subtypes for adenocarcinomas and cytologic and/or nuclear criteria for adenocarcinoma and/or squamous cell carcinomas. PMID:27356985

  9. Functionally graded boron carbide

    SciTech Connect

    Petrovic, J.J.; McClellan, K.J.; Kise, C.D.; Hoover, R.C.; Scarborough, W.K.

    1998-12-31

    Lightweight body armor is important for the protection of US soldiers in the field. Here, fabrication techniques were developed for producing graded porosity B{sub 4}C, and for producing aluminum-B{sub 4}C and epoxy-B{sub 4}C functionally graded materials. The key fabrication aspect was obtaining the graded porosity B{sub 4}C. The feasibility of producing graded porosity B{sub 4}C using a grading of carbon densification aid produced from a gradient of furfuryl alcohol carbon precursor was demonstrated. This approach is quite promising, but it was not optimized in the present investigation. Graded porosity B{sub 4}C materials were produced by a layering approach using different size distributions of B{sub 4}C powders in the green state, and then densifying the layered assembly by hot pressing at 1,900 C. The hardness of uninfiltrated graded B{sub 4}C, aluminum infiltrated B{sub 4}C, and epoxy infiltrated B{sub 4}C was observed to be similar.

  10. Nebraska Science Standards: Grades K-12

    ERIC Educational Resources Information Center

    Nebraska Department of Education, 2010

    2010-01-01

    This publication presents the Nebraska Science Standards for Grades K-12. The standards are presented according to the following grades: (1) Grades K-2; (2) Grades 3-5; (3) Grades 6-8; and (4) Grades 9-12.

  11. Methods of increasing net work output of organic Rankine cycles for low-grade waste heat recovery with a detailed analysis using a zeotropic working fluid mixture and scroll expander

    NASA Astrophysics Data System (ADS)

    Woodland, Brandon Jay

    An organic Rankine cycle (ORC) is a thermodynamic cycle that is well-suited for waste heat recovery. It is generally employed for waste heat with temperatures in the range of 80 °C -- 300 °C. When the application is strictly to convert waste heat into work, thermal efficiency is not recommended as a key performance metric. In such an application, maximization of the net power output should be the objective rather than maximization of the thermal efficiency. Two alternative cycle configurations that can increase the net power produced from a heat source with a given temperature and flow rate are proposed and analyzed. These cycle configurations are 1) an ORC with two-phase flash expansion and 2) an ORC with a zeotropic working fluid mixture (ZRC). A design-stage ORC model is presented for consistent comparison of multiple ORC configurations. The finite capacity of the heat source and heat sink fluids is a key consideration in this model. Of all working fluids studied for the baseline ORC, R134a and R245fa yield the highest net power output from a given heat source. Results of the design-stage model indicate that the ORC with two-phase flash expansion offers the most improvement over the baseline ORC. However, the level of improvement that could be achieved in practice is highly uncertain due to the requirement of highly efficient two-phase expansion. The ZRC shows improvement over the baseline as long as the condenser fan power requirement is not negligible. At the highest estimated condenser fan power, the ZRC shows the most improvement, while the ORC with flash expansion is no longer beneficial. The ZRC was selected for detailed study because it does not require two-phase expansion. An experimental test rig was used to evaluate baseline ORC performance with R134a and with R245fa. The ZRC was tested on the same rig with a mixture of 62.5% R134a and 37.5% R245fa. The tested expander is a minimally-modified, of-the-shelf automotive scroll compressor. The high

  12. Validity Decay in STEM and Non-STEM Fields of Study. ACT Working Paper Series. WP-2014-05

    ERIC Educational Resources Information Center

    Westrick, Paul A.

    2014-01-01

    The purpose of this study was to determine if validity coefficients for ACT scores and high school grade point average (HSGPA) decayed or held stable over eight semesters of undergraduate study in science, technology, engineering, and mathematics (STEM) fields at civilian four-year institutions, and whether the decay patterns differed from those…

  13. Antimatter signatures of gravitino dark matter decay

    SciTech Connect

    Ibarra, Alejandro; Tran, David E-mail: david.tran@desy.de

    2008-07-15

    The scenario of gravitino dark matter with broken R-parity naturally reconciles three paradigms that, albeit very well motivated separately, seem to be in mutual conflict: supersymmetric dark matter, thermal leptogenesis and standard big bang nucleosynthesis. Interestingly, the products of the gravitino decay could be observed, opening the possibility of indirect detection of gravitino dark matter. In this paper, we compute the positron and the antiproton fluxes from gravitino decay. We find that a gravitino with a mass of m{sub 3/2}{approx}150 GeV and a lifetime of {tau}{sub 3/2}{approx}10{sup 26} s could simultaneously explain the EGRET anomaly in the extragalactic diffuse gamma ray background and the HEAT excess in the positron fraction. However, the predicted antiproton flux tends to be too large, although the prediction suffers from large uncertainties and might be compatible with present observations for certain choices of propagation parameters.

  14. B Decays Involving Light Mesons

    SciTech Connect

    Eschrich, Ivo Gough; /UC, Irvine

    2007-01-09

    Recent BABAR results for decays of B-mesons to combinations of non-charm mesons are presented. This includes B decays to two vector mesons, B {yields} {eta}{prime}({pi}, K, {rho}) modes, and a comprehensive Dalitz Plot analysis of B {yields} KKK decays.

  15. Decay Dynamics of Tumors

    PubMed Central

    2016-01-01

    The fractional cell kill is a mathematical expression describing the rate at which a certain population of cells is reduced to a fraction of itself. We investigate the mathematical function that governs the rate at which a solid tumor is lysed by a cell population of cytotoxic lymphocytes. We do it in the context of enzyme kinetics, using geometrical and analytical arguments. We derive the equations governing the decay of a tumor in the limit in which it is plainly surrounded by immune cells. A cellular automaton is used to test such decay, confirming its validity. Finally, we introduce a modification in the fractional cell kill so that the expected dynamics is attained in the mentioned limit. We also discuss the potential of this new function for non-solid and solid tumors which are infiltrated with lymphocytes. PMID:27310010

  16. Distinction of brain tissue, low grade and high grade glioma with time-resolved fluorescence spectroscopy.

    PubMed

    Yong, William H; Butte, Pramod V; Pikul, Brian K; Jo, Javier A; Fang, Qiyin; Papaioannou, Thanassis; Black, Keith; Marcu, Laura

    2006-01-01

    Neuropathology frozen section diagnoses are difficult in part because of the small tissue samples and the paucity of adjunctive rapid intraoperative stains. This study aims to explore the use of time-resolved laser-induced fluorescence spectroscopy as a rapid adjunctive tool for the diagnosis of glioma specimens and for distinction of glioma from normal tissues intraoperatively. Ten low grade gliomas, 15 high grade gliomas without necrosis, 6 high grade gliomas with necrosis and/or radiation effect, and 14 histologically uninvolved "normal" brain specimens are spectroscopicaly analyzed and contrasted. Tissue autofluorescence was induced with a pulsed Nitrogen laser (337 nm, 1.2 ns) and the transient intensity decay profiles were recorded in the 370-500 nm spectral range with a fast digitized (0.2 ns time resolution). Spectral intensities and time-dependent parameters derived from the time-resolved spectra of each site were used for tissue characterization. A linear discriminant analysis diagnostic algorithm was used for tissue classification. Both low and high grade gliomas can be distinguished from histologically uninvolved cerebral cortex and white matter with high accuracy (above 90%). In addition, the presence or absence of treatment effect and/or necrosis can be identified in high grade gliomas. Taking advantage of tissue autofluorescence, this technique facilitates a direct and rapid investigation of surgically obtained tissue. PMID:16368511

  17. Assigning Grades More Fairly

    ERIC Educational Resources Information Center

    Cheshier, Stephen R.

    1975-01-01

    Describes a simplified method for converting raw scores to standard scores and transforming them to "T-scores" for easy comparison of performance. Obtaining letter grades from T-scores is discussed. A reading list is included. (GH)

  18. RADIATIVE PENGUIN DECAYS FROM BABAR

    SciTech Connect

    Eigen, Gerald

    2003-08-28

    Electroweak penguin decays provide a promising hunting ground for Physics beyond the Standard Model (SM). The decay B {yields} X{sub s}{gamma}, which proceeds through an electromagnetic penguin loop, already provides stringent constraints on the supersymmetric (SUSY) parameter space. The present data samples of {approx}1 x 10{sup 8} B{bar B} events allow to explore radiative penguin decays with branching fractions of the order of 10{sup -6} or less. In this brief report they discuss a study of B {yields} K*{ell}{sup +}{ell}{sup -} decay modes and a search for B {yields} {rho}({omega}){gamma} decays.

  19. Charmless b decays at CDF

    SciTech Connect

    Donega, Mauro; /Geneva U.

    2005-07-01

    The authors report on the charmless B decays measurements performed on 180 pb{sup -1} of data collected with the CDF II detector at the Fermilab Tevatron collider. This paper describes: the first observation of the decay mode B{sub s} {yields} K{sup +}K{sup -} and the measurement of the direct Cp asymmetry in the ({bar B}){sub d} {yields} K{sup {+-}}{pi}{sup {-+}} decay; the first evidence of the decay mode B{sub s} {yields} {phi}{phi} and the branching ratio and Cp asymmetry for the B{sup {+-}} {yields} {phi}K{sup {+-}} decay.

  20. Energy decay rate of the thermoelastic Bresse system

    NASA Astrophysics Data System (ADS)

    Liu, Zhuangyi; Rao, Bopeng

    2009-01-01

    In this paper, we study the energy decay rate for the thermoelastic Bresse system which describes the motion of a linear planar, shearable thermoelastic beam. If the longitudinal motion and heat transfer are neglected, this model reduces to the well-known thermoelastic Timoshenko beam equations. The system consists of three wave equations and two heat equations coupled in certain pattern. The two wave equations about the longitudinal displacement and shear angle displacement are effectively damped by the dissipation from the two heat equations. Actually, the corresponding energy decays exponentially like the classical one-dimensional thermoelastic system. However, the third wave equation about the vertical displacement is only weakly damped. Thus the decay rate of the energy of the overall system is still unknown. We will show that the exponentially decay rate is preserved when the wave speed of the vertical displacement coincides with the wave speed of longitudinal displacement or of the shear angle displacement. Otherwise, only a polynomial type decay rate can be obtained. These results are proved by verifying the frequency domain conditions.

  1. Graded pitch electromagnetic pump for thin strip metal casting systems

    DOEpatents

    Kuznetsov, S.B.

    1986-04-01

    A metal strip casing system is provided with an electromagnetic pump which includes a pair of primary blocks having a graded pole pitch, polyphase ac winding and being arranged on opposite sides of a movable heat sink. A nozzle is provided for depositing liquid metal on the heat sink such that the resulting metal strip and heat sink combination is subjected to a longitudinal electromagnetic field which increases in wavelength in the direction of travel of the heat sink, thereby subjecting the metal and heat sink to a longitudinal force having a magnitude which increases in the direction of travel. 4 figs.

  2. Graded pitch electromagnetic pump for thin strip metal casting systems

    DOEpatents

    Kuznetsov, Stephen B.

    1986-01-01

    A metal strip casing system is provided with an electromagnetic pump which includes a pair of primary blocks having a graded pole pitch, polyphase ac winding and being arranged on opposite sides of a movable heat sink. A nozzle is provided for depositing liquid metal on the heat sink such that the resulting metal strip and heat sink combination is subjected to a longitudinal electromagnetic field which increases in wavelength in the direction of travel of the heat sink, thereby subjecting the metal and heat sink to a longitudinal force having a magnitude which increases in the direction of travel.

  3. The Meaning of College Grades in Three Grading Systems.

    ERIC Educational Resources Information Center

    Eiszler, Charles F.

    1983-01-01

    To determine if college students (n=345) attribute different meanings to specific grades (depending on the nature of the grading system used), three grading systems were compared: competitive, mastery, and growth. In addition, students were asked to rate the meaning of a specific grade ("A,""B," or "C") in the context of one of the three grading…

  4. 7 CFR 810.105 - Grades and grade requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD ADMINISTRATION (FEDERAL GRAIN INSPECTION SERVICE), DEPARTMENT OF AGRICULTURE OFFICIAL UNITED STATES STANDARDS FOR GRAIN General Provisions Grades, Grade Requirements, and Grade Designations § 810.105 Grades and...

  5. 7 CFR 810.105 - Grades and grade requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD ADMINISTRATION (FEDERAL GRAIN INSPECTION SERVICE), DEPARTMENT OF AGRICULTURE OFFICIAL UNITED STATES STANDARDS FOR GRAIN General Provisions Grades, Grade Requirements, and Grade Designations § 810.105 Grades and...

  6. How Consistent Are Course Grades? An Examination of Differential Grading

    ERIC Educational Resources Information Center

    Rauschenberg, Samuel

    2014-01-01

    Differential grading occurs when students in courses with the same content and curriculum receive inconsistent grades across teachers, schools, or districts. It may be due to many factors, including differences in teacher grading standards, district grading policies, student behavior, teacher stereotypes, teacher quality, and curriculum adherence.…

  7. Dark-matter decays and self-gravitating halos

    SciTech Connect

    Peter, Annika H. G.; Moody, Christopher E.; Kamionkowski, Marc

    2010-05-15

    We consider models in which a dark-matter particle decays to a slightly less massive daughter particle and a noninteracting massless particle. The decay gives the daughter particle a small velocity kick. Self-gravitating dark-matter halos that have a virial velocity smaller than this velocity kick may be disrupted by these particle decays, while those with larger virial velocities will be heated. We use numerical simulations to follow the detailed evolution of the total mass and density profile of self-gravitating systems composed of particles that undergo such velocity kicks as a function of the kick speed (relative to the virial velocity) and the decay time (relative to the dynamical time). We show how these decays will affect the halo mass-concentration relation and mass function. Using measurements of the halo mass-concentration relation and galaxy-cluster mass function to constrain the lifetime-kick-velocity parameter space for decaying dark matter, we find roughly that the observations rule out the combination of kick velocities greater than 100 km s{sup -1} and decay times less than a few times the age of the Universe.

  8. NEANDC specialists meeting on yields and decay data of fission product nuclides

    SciTech Connect

    Chrien, R.E.; Burrows, T.W.

    1983-01-01

    Separate abstracts were prepared for the 29 papers presented. Workshop reports on decay heat, fission yields, beta- and gamma-ray spectroscopy, and delayed neutrons are included. An appendix contains a survey of the most recent compilations and evaluations containing fission product yield, fission product decay data, and delayed neutron yield information. (WHK)

  9. Rare B Decays

    SciTech Connect

    Jackson, P.D.; /Victoria U.

    2006-02-24

    Recent results from Belle and BaBar on rare B decays involving flavor-changing neutral currents or purely leptonic final states are presented. Measurements of the CP asymmetries in B {yields} K*{gamma} and b {yields} s{gamma} are reported. Also reported are updated limits on B{sup +} {yields} K{sup +}{nu}{bar {nu}}, B{sup +} {yields} {tau}{sup +}{nu}, B{sup +} {yields} {mu}{sup +}{nu} and the recent measurement of B {yields} X{sub s}{ell}{sup +}{ell}{sup -}.

  10. E6 Gamma Decay

    SciTech Connect

    Brown, B. Alex; Rae, W. D. M.

    2011-05-06

    Rare electric hexacontatetrapole (E6) transitions are studied in the full (f{sub 7/2},f{sub 5/2},p{sub 3/2},p{sub 1/2}) shell-model basis. Comparison of theory to the results from the gamma decay in {sup 53}Fe and from inelastic electron scattering on {sup 52}Cr provides unique and interesting tests of the valence wavefunctions, the models used for energy density functionals and into the origin of effective charge.

  11. Music Handbook for Primary Grades.

    ERIC Educational Resources Information Center

    Bowman, Doris; And Others

    GRADES OR AGES: Primary grades (1, 2, and 3). SUBJECT MATTER: Music. ORGANIZATION AND PHYSICAL APPEARANCE: This guide contains a detailed outline of the basic music concepts for elementary grades with suggestions for activities which may develop understanding of the concepts. The pages of activities are color coded by grade level. There are three…

  12. Arizona Academic Standards, Grade 3.

    ERIC Educational Resources Information Center

    Arizona State Department of Education, 2004

    2004-01-01

    This publication contains Arizona public schools' academic standards for grade 3. The contents of this document include the following: (1) The Arts Standards, 1997--Foundations (Grades 1-3); (2) Comprehensive Health Standards, 1997--Foundations (Grades 1-3); (3) Foreign and Native Language Standards, 1997--Foundations (Grades 1-3); (4) Reading…

  13. Arizona Academic Standards: Grade 1.

    ERIC Educational Resources Information Center

    Arizona State Department of Education, 2004

    2004-01-01

    This document contains the Arizona academic standards for Grade 1. The following 11 standards are reviewed: (1) The Arts Standards 1997 ? Foundations (Grades 1-3); (2) Comprehensive Health Standards 1997 ? Foundations (Grades 1-3); (3) Foreign and Native Language Standards 1997 ? Foundations (Grades 1-3); (4) Reading Standard Articulated by…

  14. Grading Students in Inclusive Settings.

    ERIC Educational Resources Information Center

    Salend, Spencer J.; Duhaney, Laurel M. Garrick

    2002-01-01

    This article offers guidelines for determining equitable, accountable, and effective grading practices and policies for all students that balance the need for a common set of standards and the individual needs of the students. Purposes of grading, grading systems, and effective instructional practices that support grading processes are discussed.…

  15. Arizona Academic Standards, Grade 2

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains Arizona public schools' academic standards for grade 2. The contents of this document include the following: (1) The Arts Standard 2006--Grade 2; (2) Comprehensive Health Education/Physical Activity Standards 1997--Foundations (Grades 1-3); (3) Foreign and Native Language Standards 1997--Foundations (Grades 1-3); (4)…

  16. Arizona Academic Standards, Grade 1

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains Arizona public schools' academic standards for Grade 1. The contents of this document include the following: (1) The Arts Standard 2006--Grade 1; (2) Comprehensive Health Education/Physical Activity Standards 1997--Foundations (Grades 1-3); (3) Foreign and Native Language Standards 1997--Foundations (Grades 1-3); (4)…

  17. Arizona Academic Standards: Grade 4

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains Arizona public schools' academic standards for grade 4. The contents of this document include the following: (1) The Arts Standard 2006--Grade 4; (2) Comprehensive Health Education/Physical Activity Standards 1997--Essentials (Grades 4-8); (3) Foreign and Native Language Standards 1997--Essentials (Grades 4-8); (4)…

  18. Teachers' Experiences of Unfair Grading

    ERIC Educational Resources Information Center

    Alm, Fredrik; Colnerud, Gunnel

    2015-01-01

    Grading is often perceived as one of a teacher's most difficult tasks. Despite most teachers endeavoring to grade their students as objectively as possible, many students feel that they are subject to unfair grading. The aim of this study is to describe what it is about a teacher's grading that contributes to the perception of unfairness. This…

  19. Arizona Academic Standards, Grade 3

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains Arizona public schools' academic standards for grade 3. The contents of this document include the following: (1) The Arts Standard 2006--Grade 3; (2) Comprehensive Health Education/Physical Activity Standards 1997--Foundations (Grades 1-3); (3) Foreign and Native Language Standards 1997--Foundations (Grades 1-3); (4)…

  20. Arizona Academic Standards, Grade 6

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2007

    2007-01-01

    This publication contains Arizona public schools' academic standards for grade 6. The contents of this document include the following: (1) The Arts Standard 2006--Grade 6; (2) Comprehensive Health Education/Physical Activity Standards 1997--Essentials (Grades 4-8); (3) Foreign and Native Language Standards 1997--Essentials (Grades 4-8); (4)…

  1. Arizona Academic Standards, Grade 7

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2007

    2007-01-01

    This document contains the Arizona academic standards for Grade 7. The following 11 standards are reviewed: (1) The Arts Standard 2006--Grade 7; (2) Comprehensive Health Education Physical Activity Standards 1997--Essentials (Grades 4-8); (3) Foreign and Native Language Standards 1997--Essentials (Grades 4-8); (4) Reading Standard Articulated by…

  2. Arizona Academic Standards, Grade 4

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2007

    2007-01-01

    This publication contains Arizona public schools' academic standards for grade 4. The contents of this document include the following: (1) The Arts Standard 2006--Grade 4; (2) Comprehensive Health Education/Physical Activity Standards 1997--Essentials (Grades 4-8); (3) Foreign and Native Language Standards 1997--Essentials (Grades 4-8); (4)…

  3. Arizona Academic Standards, Grade 5

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2007

    2007-01-01

    This publication contains Arizona public schools' academic standards for grade 5. The contents of this document include the following: (1) The Arts Standard 2006--Grade 5; (2) Comprehensive Health Education/Physical Activity Standards 1997--Essentials (Grades 4-8);(3) Foreign and Native Language Standards 1997--Foundations (Grades 4-8); (4)…

  4. Arizona Academic Standards, Grade 2

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2007

    2007-01-01

    This publication contains Arizona public schools' academic standards for grade 2. The contents of this document include the following: (1) The Arts Standard 2006--Grade 2; (2) Comprehensive Health Education/Physical Activity Standards 1997--Foundations (Grades 1-3); (3) Foreign and Native Language Standards 1997--Foundations (Grades 1-3); (4)…

  5. Arizona Academic Standards, Grade 8

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains the updated academic standards of Arizona for Grade 8. The contents of this document include the following: (1) The Arts Standard 2006--Grade 8; (2) Comprehensive Health Education/Physical Activity Standards 1997--Essentials (Grades 4-8); (3) Foreign and Native Language Standards 1997--Essentials (Grades 4-8); (4) Reading…

  6. Arizona Academic Standards: Grade 7

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2009

    2009-01-01

    This document contains the Arizona academic standards for Grade 7. The following 11 standards are reviewed: (1) The Arts Standard 2006 --Grade 7; (2) Comprehensive Health Education/Physical Activity Standards 1997--Essentials (Grades 4-8); (3) Foreign and Native Language Standards 1997--Essentials (Grades 4-8); (4) Reading Standard Articulated by…

  7. Eight Steps to Meaningful Grading

    ERIC Educational Resources Information Center

    Deddeh, Heather; Main, Erin; Fulkerson, Sharon Ratzlaff

    2010-01-01

    A group of teachers at Clifford Smart Middle School in Michigan's Walled Lake Consolidated School District have broken free from traditional grading in order to embrace a more meaningful grading practice. Using standards-based grading practices, they believe their grading now accurately communicates to students and parents the student's mastery…

  8. Graded-index magnonics

    NASA Astrophysics Data System (ADS)

    Davies, C. S.; Kruglyak, V. V.

    2015-10-01

    The wave solutions of the Landau-Lifshitz equation (spin waves) are characterized by some of the most complex and peculiar dispersion relations among all waves. For example, the spin-wave ("magnonic") dispersion can range from the parabolic law (typical for a quantum-mechanical electron) at short wavelengths to the nonanalytical linear type (typical for light and acoustic phonons) at long wavelengths. Moreover, the long-wavelength magnonic dispersion has a gap and is inherently anisotropic, being naturally negative for a range of relative orientations between the effective field and the spin-wave wave vector. Nonuniformities in the effective field and magnetization configurations enable the guiding and steering of spin waves in a deliberate manner and therefore represent landscapes of graded refractive index (graded magnonic index). By analogy to the fields of graded-index photonics and transformation optics, the studies of spin waves in graded magnonic landscapes can be united under the umbrella of the graded-index magnonics theme and are reviewed here with focus on the challenges and opportunities ahead of this exciting research direction.

  9. Heat Waves

    MedlinePlus

    Heat Waves Dangers we face during periods of very high temperatures include: Heat cramps: These are muscular pains and spasms due ... that the body is having trouble with the heat. If a heat wave is predicted or happening… - ...

  10. Heat emergencies

    MedlinePlus

    Heat emergencies or illnesses are caused by exposure to extreme heat and sun. Heat illnesses can be prevented by ... to regulate the temperature, and make a heat emergency more likely: Drinking alcohol before or during exposure ...

  11. The application of value-impact analysis to USI A-45: Summary report of UCLA studies on value-impact analysis in relation to USI A-45. [Decay-heat removal safety issues

    SciTech Connect

    Cave, L.; Kastenberg, W.E.

    1987-09-01

    In the Task Action Plan for Unresolved Safety Issue A-45 (After-Heat Removal) it was recognized that the value-impact (VI) analysis of possible solutions would be an essential part of the work, particularly in the later stages. Accordingly, a review of existing methods and development of a methodology to meet the specific requirements of TAP A-45 was undertaken. In this report each of the principal areas of work is described. Due to the high capital costs associated with major changes to DHR systems, values arising from avertable ''offsite costs'' (i.e., the costs of the potential effects on the health and safety of the public, both direct and indirect) would be insufficient to justify any significant changes to DHR systems simply on the grounds of cost effectiveness. Therefore, a major part of the work reported here has been a study of possible additional avertable costs that should properly be included in the ''value'' term of the V-I analysis.

  12. Wood decay at sea

    NASA Astrophysics Data System (ADS)

    Charles, François; Coston-Guarini, Jennifer; Guarini, Jean-Marc; Fanfard, Sandrine

    2016-08-01

    The oceans and seas receive coarse woody debris since the Devonian, but the kinetics of wood degradation remains one of many unanswered questions about the fate of driftwood in the marine environment. A simple gravimetric experiment was carried out at a monitoring station located at the exit of a steep, forested Mediterranean watershed in the Eastern Pyrenees. The objective was to describe and quantify, with standardized logs (in shape, structure and constitution), natural degradation of wood in the sea. Results show that the mass decrease of wood logs over time can be described by a sigmoidal curve. The primary process of wood decay observed at the monitoring station was due to the arrival and installation of wood-boring species that consumed more than half of the total wood mass in six months. Surprisingly, in a region where there is little remaining wood marine infrastructure, "shipworms", i.e. xylophagous bivalves, are responsible for an important part of this wood decay. This suggests that these communities are maintained probably by a frequent supply of a large quantity of riparian wood entering the marine environment adjacent to the watershed. By exploring this direct link between terrestrial and marine ecosystems, our long term objective is to determine how these supplies of terrestrial organic carbon can sustain wood-based marine communities as it is observed in the Mediterranean Sea.

  13. Virus decay and its causes in coastal waters.

    PubMed

    Noble, R T; Fuhrman, J A

    1997-01-01

    Recent evidence suggests that viruses play an influential role within the marine microbial food web. To understand this role, it is important to determine rates and mechanisms of virus removal and degradation. We used plaque assays to examine the decay of infectivity in lab-grown viruses seeded into natural seawater. The rates of loss of infectivity of native viruses from Santa Monica Bay and of nonnative viruses from the North Sea in the coastal seawater of Santa Monica Bay were determined. Viruses were seeded into fresh seawater that had been pretreated in various ways: filtration with a 0.2-(mu)m-pore-size filter to remove organisms, heat to denature enzymes, and dissolved organic matter enrichment to reconstitute enzyme activity. Seawater samples were then incubated in full sunlight, in the dark, or under glass to allow partitioning of causative agents of virus decay. Solar radiation always resulted in increased rates of loss of virus infectivity. Virus isolates which are native to Santa Monica Bay consistently degraded more slowly in full sunlight in untreated seawater (decay ranged from 4.1 to 7.2% h(sup-1)) than nonnative marine bacteriophages which were isolated from the North Sea (decay ranged from 6.6 to 11.1% h(sup-1)). All phages demonstrated susceptibility to degradation by heat-labile substances, as heat treatment reduced the decay rates to about 0.5 to 2.0% h(sup-1) in the dark. Filtration reduced decay rates by various amounts, averaging 20%. Heat-labile, high-molecular-weight dissolved material (>30 kDa, probably enzymes) appeared responsible for about 1/5 of the maximal decay. Solar radiation was responsible for about 1/3 to 2/3 of the maximal decay of nonnative viruses and about 1/4 to 1/3 of that of the native viruses, suggesting evolutionary adaptation to local light levels. Our results suggest that sunlight is an important contributing factor to virus decay but also point to the significance of particles and dissolved substances in seawater

  14. Alpha decay in electron surrounding

    SciTech Connect

    Igashov, S. Yu.; Tchuvil’sky, Yu. M.

    2013-12-15

    The influence of atomic electron shells on the constant of alpha decay of heavy and mediummass nuclei was considered in detail. A method for simultaneously taking into account the change in the potential-barrier shape and the effect of reflection of a diverging Coulomb wave in the classically allowed region was developed. The ratios of decay probabilities per unit time for a bare nucleus and the respective neutral atom were found for some alpha-decaying isotopes.

  15. Search for rare B decays

    NASA Astrophysics Data System (ADS)

    Albrecht, H.; Hamacher, T.; Hofmann, R. P.; Kirchhoff, T.; Mankel, R.; Nau, A.; Nowak, S.; Reßing, D.; Schröder, H.; Schulz, H. D.; Walter, M.; Wurth, R.; Hast, C.; Kapitza, H.; Kolanoski, H.; Kosche, A.; Lange, A.; Lindner, A.; Schieber, M.; Siegmund, T.; Spaan, B.; Thurn, H.; Töpfer, D.; Wegener, D.; Eckstein, P.; Frankl, C.; Graf, J.; Schmidtler, M.; Schramm, M.; Schubert, K. R.; Schwierz, R.; Waldi, R.; Reim, K.; Wegener, H.; Eckmann, R.; Kuipers, H.; Mai, O.; Mundt, R.; Oest, T.; Reiner, R.; Schmidt-Parzefall, W.; Stiewe, J.; Werner, S.; Ehret, K.; Hofmann, W.; Hüpper, A.; Knöpfle, K. T.; Spengler, J.; Krieger, P.; Macfarlane, D. B.; Prentice, J. D.; Saull, P. R. B.; Tzamariudaki, K.; van de Water, R. G.; Yoon, T.-S.; Schneider, M.; Weseler, S.; Kernel, G.; Križan, P.; Križnič, E.; Podobnik, T.; Živko, T.; Balagura, V.; Barsuk, S.; Belyaev, I.; Chistov, R.; Danilov, M.; Gershtein, L.; Gershtein, Yu.; Golutyin, A.; Korolko, I.; Kostina, G.; Litvintsev, D.; Pakhlov, P.; Semenov, S.; Snizhko, A.; Tichomirov, I.; Zaitsev, Yu.; Argus Collaboration

    1995-02-01

    Using the ARGUS detector at the e +e - storage ring DORIS II at DESY, we have searched for decays b → sgluon through full reconstruction of a whole event. Two B overlineB decays were found with one of B meson decaying into a final state without charmed particles. We also obtained an upper limit of Br(B + → τ+ντ) of 1.04% at 90% CL.

  16. On nonlocal electron heat conduction

    SciTech Connect

    Krasheninnikov, S.I. )

    1993-01-01

    An improvement of the Albritton nonlocal electron heat transport model is proposed for high-[ital Z] plasmas. The thermal decay of the temperature perturbation in a uniform plasma as calculated by this model is compared with that obtained by Fokker--Planck simulations. Complete agreement is found up to values [ital k][lambda][sub [ital e

  17. CP violation in K decays and rare decays

    SciTech Connect

    Buchalla, G.

    1996-12-01

    The present status of CP violation in decays of neutral kaons is reviewed. In addition selected rare decays of both K and B mesons are discussed. The emphasis is in particular on observables that can be reliably calculated and thus offer the possibility of clean tests of standard model flavor physics. 105 refs.

  18. Career Awareness: Grade 5.

    ERIC Educational Resources Information Center

    Boise City Independent School District, ID.

    A broad educational background is necessary to meet ever changing occupational fields, and career education is an approach incorporating career information within regular school curriculum. For the elementary level, career awareness is the main thrust in this program to integrate students and community. The format for grade five, performance…

  19. Hungarian Graded Reader.

    ERIC Educational Resources Information Center

    Mihalyfy, Ilona; Koski, Augustus A.

    This graded reader is intended to supplement a beginning course in Hungarian after the student has "developed control of about 700 lexical items and can manipulate with fluency much of the basic structure of Hungarian." (It may also be used in an intermediate course.) The 56 reading selections are varied in content and sequenced to develop reading…

  20. Finnish Graded Reader.

    ERIC Educational Resources Information Center

    Bell, Aili Rytkonen; Koski, Augustus A.

    This audiolingual text is designed to serve as supplementary material for a beginning course in Finnish, to be introduced "when the student has mastered much of the basic structure of Finnish and about 700 lexical items." The authors suggest that it may also be used as an intermediate course. The text comprises 57 graded reading selections…

  1. American Independence. Fifth Grade.

    ERIC Educational Resources Information Center

    Crosby, Annette

    This fifth grade teaching unit covers early conflicts between the American colonies and Britain, battles of the American Revolutionary War, and the Declaration of Independence. Knowledge goals address the pre-revolutionary acts enforced by the British, the concepts of conflict and independence, and the major events and significant people from the…

  2. Grades as Information

    ERIC Educational Resources Information Center

    Grant, Darren

    2007-01-01

    We determine how much observed student performance in microeconomics principles can be attributed, inferentially, to three kinds of student academic "productivity," the instructor, demographics, and unmeasurables. The empirical approach utilizes an ordered probit model that relates student performance in micro to grades in prior coursework,…

  3. Health, Grade 3.

    ERIC Educational Resources Information Center

    Bui Van Bao; And Others

    This is the third in a series of health primers for elementary education in Vietnam. It is written for Vietnamese children at the third grade level. The fifty-three lessons are integrated into one story. Each lesson is illustrated and briefly summarized. The eight chapters are: (1) Hygiene, at home, in school and in public places; (2) Food and…

  4. Computer grading of examinations

    NASA Technical Reports Server (NTRS)

    Frigerio, N. A.

    1969-01-01

    A method, using IBM cards and computer processing, automates examination grading and recording and permits use of computational problems. The student generates his own answers, and the instructor has much greater freedom in writing questions than is possible with multiple choice examinations.

  5. American Megalopolises, Grade 3.

    ERIC Educational Resources Information Center

    Bowers, Judy

    This is a third-grade teaching unit on large cities (megalopolises) in the United States. The components of the unit are: (1) a content outline, (2) unit goals, (3) unit objectives, (4) activities, (5) unit evaluation, and (6) bibliography. The content of the unit focuses on defining a megalopolis, noting what can be found in it, its special…

  6. Purpose-Driven Grading

    ERIC Educational Resources Information Center

    Carlson, Jane A. K.; Kimpton, Ann

    2010-01-01

    Allowing students to improve their grade by revising their written work may help students learn to revise, but it gives them no incentive to turn in quality work from the start. This article proposes a way to invert the process, thereby teaching students how to revise, while enforcing a more disciplined approach to good writing. (Contains 3…

  7. First Grade Baseline Evaluation

    ERIC Educational Resources Information Center

    Center for Innovation in Assessment (NJ1), 2013

    2013-01-01

    The First Grade Baseline Evaluation is an optional tool that can be used at the beginning of the school year to help teachers get to know the reading and language skills of each student. The evaluation is composed of seven screenings. Teachers may use the entire evaluation or choose to use those individual screenings that they find most beneficial…

  8. Middle Grades Ideas.

    ERIC Educational Resources Information Center

    Classroom Computer Learning, 1984

    1984-01-01

    Presented are six activities suitable for middle grades. They include programs for voting, creating Logo patterns, and for selecting a writing topic. Other activities focus on use of the colon and FOR/NEXT loop in BASIC and evaluating programs. (JN)

  9. Middle Grades Ideas.

    ERIC Educational Resources Information Center

    Classroom Computer Learning, 1984

    1984-01-01

    Presents five activities suitable for middle grades. These include listings for a car race (BASIC) and poetry (Pilot) programs, and activities on graphics without programing, new meanings (related to computers) of old words, and developing a list of historical events. (JN)

  10. Early Grades Ideas.

    ERIC Educational Resources Information Center

    Classroom Computer Learning, 1984

    1984-01-01

    Presents computer-oriented teaching suggestions suitable for early grades. They include creating houses and stained glass ornaments using Logo, recording class activities with a database management program, making mazes with graphics programs, making drawings with a KoalaPad, and using a program to introduce computers to non-English speaking…

  11. Health, Grade 5.

    ERIC Educational Resources Information Center

    Bui Van Bao; And Others

    This is the fifth and last of the Vietnamese series of elementary health textbooks. This one was designed for fifth grade students in Vietnam. The thirty-five lessons are presented in the form of short stories with illustrations and a short summary. The four chapters cover the ordinary symptoms of illness, elementary notions of microbes and…

  12. Early Grades Ideas.

    ERIC Educational Resources Information Center

    Classroom Computer Learning, 1985

    1985-01-01

    Presents a collection of computer-oriented teaching activities for the early grades. They include creating musical tones using Atari PILOT, a simulation of traffic lights, teacher-friendly password protection, drawing the alphabet using Logo, and using the Commodore 64's special character graphics. (JN)

  13. Social Studies: Grade 8.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education, Winnipeg.

    This Manitoba (Canada) curriculum guide for eighth grade social studies students contains suggested teaching strategies and learning activities in four units covering: (1) life during prehistoric and early historic times; (2) ancient civilizations; (3) life in early modern Europe; and (4) life in the modern world. Each unit includes an overview,…

  14. Second-Grade "Professors"

    ERIC Educational Resources Information Center

    Wu, Zhonghe; An, Shuhua; King, Joyce; Ramirez, Melissa; Evans, Stacee

    2009-01-01

    Finding ways to help primary-grade students overcome difficulties in solving mathematical word problems can be a daunting task for teachers in a regular classroom setting. Student challenges may include: (1) difficulty with vocabulary; (2) lack of confidence when solving problems; (3) confusion on the proper operation to use when solving a…

  15. Endangered Animals. Second Grade.

    ERIC Educational Resources Information Center

    Popp, Marcia

    This second grade teaching unit centers on endangered animal species around the world. Questions addressed are: What is an endangered species? Why do animals become extinct? How do I feel about the problem? and What can I do? Students study the definition of endangered species and investigate whether it is a natural process. They explore topics…

  16. Modern Problems. Grade 12.

    ERIC Educational Resources Information Center

    Wilmington Public Schools, DE.

    The general purpose of the twelfth grade course is to help the student assume his role as a decision-maker in a democratic society. The nature and complexity of contemporary problems are examined using this guide to enable the student: 1) to analyze alternative solutions to these problems; 2) to develop attitudes and values appropriate to a…

  17. Cutting Class Harms Grades

    ERIC Educational Resources Information Center

    Taylor, Lewis A., III

    2012-01-01

    An accessible business school population of undergraduate students was investigated in three independent, but related studies to determine effects on grades due to cutting class and failing to take advantage of optional reviews and study quizzes. It was hypothesized that cutting classes harms exam scores, attending preexam reviews helps exam…

  18. Elementary Science: Grade 2.

    ERIC Educational Resources Information Center

    Carroll County Public Schools, Westminster, MD.

    This grade 2 science curriculum guide contains three activity units: (1) insects; (2) measuring; and (3) sink or float. Each unit contains a rationale, teacher background material, lesson plans, and lists of resources including books, audiovisual materials, resource persons, and science activity modules. The lesson plans list the science processes…

  19. Student Grade History System.

    ERIC Educational Resources Information Center

    White, Stephen R.

    This document describes the computerized procedures developed and utilized by Montgomery College (Maryland) to maintain records related to student academic progress. The new system was fully operable by fall 1972. Systems development included: (1) the conversion of past student records to a permanent grade history file; (2) the development of a…

  20. ARITHMETIC, GRADE FIVE.

    ERIC Educational Resources Information Center

    GARBER, CLAIRE N.

    FIFTH GRADE WORK SHOULD CONTINUE THE SEQUENTIAL DEVELOPMENT OF MATHEMATICAL UNDERSTANDINGS AND COMPUTATIONAL SKILLS. THE PROBLEMS APPROACH SHOULD BE USED SO CHILDREN MAY DISCOVER MATHEMATICAL TRUTHS AND ARRIVE AT GENERALIZATIONS. THE NUMBER SYSTEM UNIT SHOULD EMPHASIZE THE ABILITY TO READ AND WRITE NUMERALS TO SIX PLACES AND THE ABILITY TO READ…

  1. Elementary Science: Grade 5.

    ERIC Educational Resources Information Center

    Carroll County Public Schools, Westminster, MD.

    This grade 5 science curriculum guide contains four activity units: (1) mineral identification; (2) earth science; (3) soil analysis; and (4) small friends community. Each unit contains a letter to the parents to introduce the unit, lesson plans, and word searches. The lesson plans list the science processes involved, content objectives,…

  2. Student Almanac. Grade Five.

    ERIC Educational Resources Information Center

    Minnesota Univ., Minneapolis. Project Social Studies Curriculum Center.

    This almanac is designed for use in the fifth grade course on regional studies which focuses on several case studies rather than on detailed study of each region. (The course is described in ED 062 226). For that reason the factual information is selected and includes figures relevant to the case studies in the regional areas of the Midwest, North…

  3. Graded SPSS Exercises.

    ERIC Educational Resources Information Center

    Allen, Mary J.

    The attached materials have been developed for use on the CSU CYBER Computer's Statistical Package for the Social Sciences (SPSSONL). The assignments are graded in difficulty and gradually introduce new commands and require the practice of previously learned commands. The handouts begin with basic instructions for logging on; then XEDIT is taught…

  4. Graphing for Any Grade.

    ERIC Educational Resources Information Center

    Nibbelink, William

    1982-01-01

    An instructional sequence for teaching graphing that has been extensively field tested in kindergarten through grade six is detailed. The material begins with point graphs, employs a movable y-axis to begin with minimal clutter, and has graphs constructed before reading graphs is required. (MP)

  5. Career Awareness: Grade 6.

    ERIC Educational Resources Information Center

    Boise City Independent School District, ID.

    A broad educational background is necessary to meet ever changing occupational fields, and career education is an approach incorporating career information within the regular school curriculum. For the elementary level, career awareness is the main thrust in this program to integrate students and community. The format for grade six, performance…

  6. Measurement of fission products β decay properties using a total absorption spectrometer

    NASA Astrophysics Data System (ADS)

    Zakari-Issoufou, A.-A.; Porta, A.; Fallot, M.; Algora, A.; Tain, J. L.; Valencia, E.; Rice, S.; Agramunt, J.; Äystö, J.; Bowry, M.; Bui, V. M.; Caballero-Folch, R.; Cano-Ott, D.; Eloma, V.; Estévez, E.; Farrelly, G. F.; Garcia, A.; Gelletly, W.; Gomez-Hornillos, M. B.; Gorlychev, V.; Hakala, J.; Jokinen, A.; Jordan, M. D.; Kankainen, A.; Kondev, F. G.; Martinez, T.; Mendoza, E.; Molina, F.; Moore, I.; Perez, A.; Podolyak, Zs.; Penttilä, H.; Regan, P. H.; Rissanen, J.; Rubio, B.; Weber, C.

    2013-12-01

    In a nuclear reactor, the β decay of fission fragments is at the origin of decay heat and antineutrino flux. These quantities are not well known while they are very important for reactor safety and for our understanding of neutrino physics. One reason for the discrepancies observed in the estimation of the decay heat and antineutrinos flux coming from reactors could be linked with the Pandemonium effect. New measurements have been performed at the JYFL facility of Jyväskylä with a Total Absorption Spectrometer (TAS) in order to circumvent this effect. An overview of the TAS technique and first results from the 2009 measurement campaign will be presented.

  7. Timing and heat sources for the Barrovian metamorphism, Scotland

    NASA Astrophysics Data System (ADS)

    Viete, Daniel R.; Oliver, Grahame J. H.; Fraser, Geoff L.; Forster, Marnie A.; Lister, Gordon S.

    2013-09-01

    New SHRIMP U/Pb zircon ages of 472.2 ± 5.8 Ma and 471.2 ± 5.9 Ma are presented for the age of peak metamorphism of Barrovian migmatites. 40Ar/39Ar ages for white mica from the Barrovian metamorphic series are presented, and are recalculated using recently-proposed revisions to the 40K decay constants to allow more precise and accurate comparison with U/Pb ages. The 40Ar/39Ar ages are found to vary systematically with increasing metamorphic grade, between c. 465 Ma for the biotite zone and c. 461 Ma for the sillimanite zone. There is no evidence for any significant metamorphic heating during the first 15 Myr of the Grampian Orogeny (before c. 473 Ma) or the final 4 Myr (after c. 465 Ma). The Barrovian metamorphism occurred over a period of ~ 8 Myr within the ~ 27-Myr Grampian Orogeny. The Barrovian metamorphism records punctuated heating, was temporally and spatially associated with large-scale bimodal magmatism, and developed within crust that was not overthickened. The temporally distinct nature of the Barrovian metamorphic episode within the Grampian Orogeny, and its heating pattern and tectonic context, are not consistent with significant heat contribution from thermal equilibration of overthickened crust. Rather, the Barrovian metamorphism records a transient phase of crustal thermal disequilibrium during the Grampian Orogeny. Temporal and spatial association with Grampian bimodal magmatism is consistent with production of the Barrovian metamorphic series within the middle crust as the result of advection of heat from the lower crust and/or mantle. The Barrovian metamorphic series - the classic example of ‘orogenic regional metamorphism’ - did not form in response to crustal thickening and thermal relaxation, but appears to record large-scale contact metamorphism.

  8. The Sticking Place: Another Look at Grades and Grading.

    ERIC Educational Resources Information Center

    Blynt, Ruth Ann

    1992-01-01

    Maintains that putting a number or letter grade on student writing is fundamentally wrong. Argues that trashing the traditional grading system is the best thing that could be done to ensure better reading and writing among students. (SR)

  9. Tau decays: A theoretical perspective

    SciTech Connect

    Marciano, W.J.

    1992-11-01

    Theoretical predictions for various tau decay rates are reviewed. Effects of electroweak radiative corrections are described. Implications for precision tests of the standard model and ``new physics`` searches are discussed. A perspective on the tau decay puzzle and 1-prong problem is given.

  10. Tau decays: A theoretical perspective

    SciTech Connect

    Marciano, W.J.

    1992-11-01

    Theoretical predictions for various tau decay rates are reviewed. Effects of electroweak radiative corrections are described. Implications for precision tests of the standard model and new physics'' searches are discussed. A perspective on the tau decay puzzle and 1-prong problem is given.

  11. Theoretical understanding of charm decays

    SciTech Connect

    Bigi, I.I.

    1986-08-01

    A detailed description of charm decays has emerged. The various concepts involved are sketched. Although this description is quite successful in reproducing the data the chapter on heavy flavour decays is far from closed. Relevant questions like on th real strength of weak annihilation, Penguin operators, etc. are still unanswered. Important directions in future work, both on the experimental and theoretical side are identified.

  12. Counterflow driven by swirl decay

    NASA Astrophysics Data System (ADS)

    Shtern, Vladimir N.; Borissov, Anatoli A.

    2010-06-01

    The global meridional circulation of a viscous fluid, caused by swirl decay in a cylindrical container, is studied. To this end, a new solution to the Navier-Stokes equations is obtained, and simple experiments are performed to verify the predictions of the theory. The swirl decay mechanism explains elongated counterflows in hydrocyclones and vortex tubes sometimes extending over a hundred diameters.

  13. Heat Without Heat

    NASA Astrophysics Data System (ADS)

    Lubkin, Elihu

    1997-04-01

    Logic of the Second Law of Thermodynamics demands acquisition of naked entropy. Accordingly, the leanest liaison between systems is not a diathermic membrane, it is a purely informational tickler, leaking no appreciable energy. The subsystem here is a thermodynamic universe, which gets `heated' entropically, yet without gaining calories. Quantum Mechanics graciously supports that(Lubkin, E. and Lubkin, T., International Journal of Theoretical Physics,32), 933-943 (1993) (at a cost of about 1 bit) through entanglement---across this least permeable of membranes---with what is beyond that universe. Heat without heat(Also v. forthcoming Proceedings of the 4th Drexel University Conference of September 1994) is the aspirin for Boltzmann's headache, conserving entropy in mechanical isolation, even while increasing entropy in thermodynamic isolation.

  14. Top decays in extended models

    SciTech Connect

    Gaitan, R.; Miranda, O. G.; Cabral-Rosetti, L. G.

    2009-04-20

    Top quark decays are interesting as a mean to test the Standard Model (SM) predictions. The Cabbibo-Kobayashi-Maskawa (CKM)-suppressed process t{yields}cWW, and the rare decays t{yields}cZ, t{yields}H{sup 0}+c, and t{yields}c{gamma} an excellent window to probe the predictions of theories beyond the SM. We evaluate the flavor changing neutral currents (FCNC) decay t{yields}H{sup 0}+c in the context of Alternative Left-Right symmetric Models (ALRM) with extra isosinglet heavy fermions; the FCNC decays may place at tree level and are only supressed by the mixing between ordinary top and charm quarks. We also comment on the decay process t{yields}c+{gamma}, which involves radiative corrections.

  15. Logarithmic decays of unstable states

    NASA Astrophysics Data System (ADS)

    Giraldi, Filippo

    2015-01-01

    It is known that the survival amplitude of unstable quantum states deviates from exponential relaxations and exhibits decays that depend on the integral and analytic properties of the energy distribution density. In the same scenario, model independent dominant logarithmic decays t -1- α0log t of the survival amplitude are induced over long times by special conditions on the energy distribution density. While the instantaneous decay rate exhibits the dominant long time relaxation 1 / t, the instantaneous energy tends to the minimum value of the energy spectrum with the dominant logarithmic decay 1/( tlog 2 t) over long times. Similar logarithmic relaxations have already been found in the dynamics of short range potential systems with even dimensional space or in the Weisskopf-Wigner model of spontaneous emission from a two-level atom. Here, logarithmic decays are obtained as a pure model independent quantum effect in general unstable states.

  16. 7 CFR 810.1404 - Grades and grade requirements for sorghum.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Unknown foreign substance 3 3 3 3 Cockleburs 7 7 7 7 Total 3 10 10 10 10 U.S. Sample grade is sorghum that... animal filth, castor beans, crotalaria seeds, glass, stones, unknown foreign substance or cockleburs... kernels: Heat (part of total) 0.2 0.5 1.0 3.0 Total 2.0 5.0 10.0 15.0 Broken kernels and foreign...

  17. 7 CFR 810.1404 - Grades and grade requirements for sorghum.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Unknown foreign substance 3 3 3 3 Cockleburs 7 7 7 7 Total 3 10 10 10 10 U.S. Sample grade is sorghum that... animal filth, castor beans, crotalaria seeds, glass, stones, unknown foreign substance or cockleburs... kernels: Heat (part of total) 0.2 0.5 1.0 3.0 Total 2.0 5.0 10.0 15.0 Broken kernels and foreign...

  18. Partial radiogenic heat model for Earth revealed by geoneutrino measurements

    NASA Astrophysics Data System (ADS)

    Kamland Collaboration; Gando, A.; Gando, Y.; Ichimura, K.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Morikawa, T.; Nagai, N.; Nakajima, K.; Nakamura, K.; Narita, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takahashi, H.; Takahashi, N.; Takemoto, Y.; Tamae, K.; Watanabe, H.; Xu, B. D.; Yabumoto, H.; Yoshida, H.; Yoshida, S.; Enomoto, S.; Kozlov, A.; Murayama, H.; Grant, C.; Keefer, G.; Piepke, A.; Banks, T. I.; Bloxham, T.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Han, K.; Kadel, R.; O'Donnell, T.; Steiner, H. M.; Dwyer, D. A.; McKeown, R. D.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Sakai, M.; Horton-Smith, G. A.; Downum, K. E.; Gratta, G.; Tolich, K.; Efremenko, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Heeger, K. M.; Decowski, M. P.

    2011-09-01

    The Earth has cooled since its formation, yet the decay of radiogenic isotopes, and in particular uranium, thorium and potassium, in the planet's interior provides a continuing heat source. The current total heat flux from the Earth to space is 44.2+/-1.0TW, but the relative contributions from residual primordial heat and radiogenic decay remain uncertain. However, radiogenic decay can be estimated from the flux of geoneutrinos, electrically neutral particles that are emitted during radioactive decay and can pass through the Earth virtually unaffected. Here we combine precise measurements of the geoneutrino flux from the Kamioka Liquid-Scintillator Antineutrino Detector, Japan, with existing measurements from the Borexino detector, Italy. We find that decay of uranium-238 and thorium-232 together contribute TW to Earth's heat flux. The neutrinos emitted from the decay of potassium-40 are below the limits of detection in our experiments, but are known to contribute 4TW. Taken together, our observations indicate that heat from radioactive decay contributes about half of Earth's total heat flux. We therefore conclude that Earth's primordial heat supply has not yet been exhausted.

  19. The Grades Transfer from One Grading Scale to Other Algorithmization

    ERIC Educational Resources Information Center

    Lieponiene, Jurgita; Kulvietiene, Regina

    2011-01-01

    The article presents the consideration of grading scales used for education outcomes in different countries, describes likeness and differences of applied grading scales. Application of the European Credit Transfer and Accumulation System (ECTS) grading scale is investigated according of the analysis of scientific literature as well as cases of…

  20. Graded Readers: How the Publishers Make the Grade

    ERIC Educational Resources Information Center

    Claridge, Gillian

    2012-01-01

    Publishing graded readers is big business, but there is evidence that the texts themselves are not being read in sufficient quantity to improve language proficiency. This article reports on a study of graded readers, focusing on interviews with some major publishers of graded readers, to investigate their production rationales. The findings…

  1. Write More, Grade Less: Five Practices for Effectively Grading Writing

    ERIC Educational Resources Information Center

    Lucas, Lisa

    2012-01-01

    One of the dilemmas that teachers frequently face is grading student papers. As a teacher, the author regularly reads research regarding instructional practices, grading, and assessment, but struggled to translate theory into practice in her own classroom. The intent of this article is to share one method of instructing and grading writing that…

  2. 7 CFR 51.304 - Combination grades.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Apples Grades § 51.304 Combination grades. (a) Combinations of the above grades may... permitted in connection with the U.S. apple grades. When Combination grades are packed, at least 50 percent of the apples in any lot shall meet the requirements of the higher grade in the combination....

  3. 7 CFR 51.304 - Combination grades.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Apples Grades § 51.304 Combination grades. (a) Combinations of the above grades may... permitted in connection with the U.S. apple grades. When Combination grades are packed, at least 50 percent of the apples in any lot shall meet the requirements of the higher grade in the combination....

  4. 7 CFR 51.304 - Combination grades.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Apples Grades § 51.304 Combination grades. (a) Combinations of the above grades may... permitted in connection with the U.S. apple grades. When Combination grades are packed, at least 50 percent of the apples in any lot shall meet the requirements of the higher grade in the combination....

  5. Design of the 1.5 MW, 30-96 MHz ultra-wideband 3 dB high power hybrid coupler for Ion Cyclotron Resonance Frequency (ICRF) heating in fusion grade reactor

    NASA Astrophysics Data System (ADS)

    Yadav, Rana Pratap; Kumar, Sunil; Kulkarni, S. V.

    2016-01-01

    Design and developmental procedure of strip-line based 1.5 MW, 30-96 MHz, ultra-wideband high power 3 dB hybrid coupler has been presented and its applicability in ion cyclotron resonance heating (ICRH) in tokamak is discussed. For the high power handling capability, spacing between conductors and ground need to very high. Hence other structural parameters like strip-width, strip thickness coupling gap, and junction also become large which can be gone upto optimum limit where various constrains like fabrication tolerance, discontinuities, and excitation of higher TE and TM modes become prominent and significantly deteriorates the desired parameters of the coupled lines system. In designed hybrid coupler, two 8.34 dB coupled lines are connected in tandem to get desired coupling of 3 dB and air is used as dielectric. The spacing between ground and conductors are taken as 0.164 m for 1.5 MW power handling capability. To have the desired spacing, each of 8.34 dB segments are designed with inner dimension of 3.6 × 1.0 × 40 cm where constraints have been significantly realized, compensated, and applied in designing of 1.5 MW hybrid coupler and presented in paper.

  6. Design of the 1.5 MW, 30-96 MHz ultra-wideband 3 dB high power hybrid coupler for Ion Cyclotron Resonance Frequency (ICRF) heating in fusion grade reactor.

    PubMed

    Yadav, Rana Pratap; Kumar, Sunil; Kulkarni, S V

    2016-01-01

    Design and developmental procedure of strip-line based 1.5 MW, 30-96 MHz, ultra-wideband high power 3 dB hybrid coupler has been presented and its applicability in ion cyclotron resonance heating (ICRH) in tokamak is discussed. For the high power handling capability, spacing between conductors and ground need to very high. Hence other structural parameters like strip-width, strip thickness coupling gap, and junction also become large which can be gone upto optimum limit where various constrains like fabrication tolerance, discontinuities, and excitation of higher TE and TM modes become prominent and significantly deteriorates the desired parameters of the coupled lines system. In designed hybrid coupler, two 8.34 dB coupled lines are connected in tandem to get desired coupling of 3 dB and air is used as dielectric. The spacing between ground and conductors are taken as 0.164 m for 1.5 MW power handling capability. To have the desired spacing, each of 8.34 dB segments are designed with inner dimension of 3.6 × 1.0 × 40 cm where constraints have been significantly realized, compensated, and applied in designing of 1.5 MW hybrid coupler and presented in paper. PMID:26827337

  7. Grade Inflation: Metaphor and Reality

    ERIC Educational Resources Information Center

    Kamber, Richard; Biggs, Mary

    2003-01-01

    Grade inflation has become a general term for teachers and administrators in recent times and is an ambiguous denomination which needs to be identified. The allegory and reality of grade inflation is discussed.

  8. Determinants for grading Malaysian rice

    NASA Astrophysics Data System (ADS)

    ChePa, Noraziah; Yusoff, Nooraini; Ahmad, Norhayati

    2016-08-01

    Due to un-uniformity of rice grading practices in Malaysia, zones which actively producing rice in Malaysia are using their own way of grading rice. Rice grading is important in determining rice quality and its subsequent price in the market. It is an important process applied in the rice production industry with the purpose of ensuring that the rice produced for the market meets the quality requirements of consumer. Two important aspects that need to be considered in determining rice grades are grading technique and determinants to be used for grading (usually referred as rice attributes). This article proposes the list of determinants to be used in grading Malaysian rice. Determinants were explored through combination of extensive literature review and series of interview with the domain experts and practitioners. The proposed determinants are believed to be beneficial to BERNAS in improving the current Malaysian rice grading process.

  9. Beauty meson decays to charmonium

    NASA Astrophysics Data System (ADS)

    Ershov, Alexey Valerievich

    2001-10-01

    We study decays of beauty (B) mesons into the final states containing charmonium mesons. The data were collected by the CLEO experiment at the Cornell Electron Storage Ring from 1990 to 1999. First, we describe a technique that significantly improves the reconstruction efficiency for decays of J/ y and y (2S) mesons into a pair of leptons. This reconstruction method is used in all the analyses presented in this dissertation. Then we present a study of B decays to the χc 1 and χc2 charmonium states and compare our results with the predictions of different theoretical models of charmonium production. After that we report the first observation of the decay B --> J/ y φK, which is the first B meson decay requiring a creation of an additional ss¯ quark pair. Then we measure the B0 and B+ meson masses from B0 --> y (') K0S and B+ --> y (') K+ decays. The method employed eliminates the dominant systematic uncertainty associated with the previous B meson mass measurements at the e+e- colliders and results in a significant improvement in precision. After that we present a study of three B0 decay modes useful for time-dependent CP asymmetry measurements. In this study we reconstruct B0 --> J/ y K0S , B0 --> χc 1 K0S , and B0 --> J/ y π0 decays. The latter two decay modes are observed for the first time. We describe a K0S --> π0π0 detection technique and its application to the reconstruction of the decay B 0 --> J/ y K0S . Then we present a sensitivity study for the measurement of the mixing-induced CP violation in the neutral B meson system (parameter sin 2β) at CLEO using the method that requires a measurement of the decay time of only one meson in a B0overline B0 pair. Finally, we search for direct CP violation in decays B+/- --> J/ y K+/- and B +/- --> y (2S) K+/- . The results of this search are consistent with the Standard Model expectations and provide the first experimental test of the assumption that direct CP violation is negligible in B --> y (') K decays.

  10. Primordial nucleosynthesis with decaying particles. I - Entropy-producing decays. II - Inert decays

    NASA Technical Reports Server (NTRS)

    Scherrer, Robert J.; Turner, Michael S.

    1988-01-01

    The effect of a nonrelativistic particle X, which decays out of equilibrium, on primordial nucleosynthesis is investigated, including both the energy density of the X particle and the electromagnetic entropy production from its decay. The results are parametrized in terms of the X particle lifetime and the density parameter rm(X), where m(X) is the X particle mass and r is the ratio of X number density to photon number density prior to nucleosynthesis. The results rule out particle lifetimes greater than 1-10 s for large values of rm(X). The question of a decaying particle which produces no electromagnetic entropy in the course of its decay is addressed, and particles which produce both entropy and an inert component in their decay are discussed.

  11. Taking the Grading Conversation Public

    ERIC Educational Resources Information Center

    Reeves, Douglas B.

    2011-01-01

    To manage effective grading reform, education leaders must engage teachers, parents, communities, and policymakers in a rational discussion about grading. Doug Reeves suggests that leaders start the conversation with a discussion of the principles on which all stakeholders can agree; make clear what will not change under the new grading policy; be…

  12. Four Steps in Grading Reform

    ERIC Educational Resources Information Center

    Guskey, Thomas R.; Jung, Lee Ann

    2012-01-01

    The field of education is moving rapidly toward a standards-based approach to grading. School leaders have become increasingly aware of the tremendous variation that exists in grading practices, even among teachers of the same courses in the same department in the same school. Consequently, students' grades often have little relation to their…

  13. A New Framework for Grading

    ERIC Educational Resources Information Center

    Green, Kris H.; Emerson, Allen

    2007-01-01

    Grading is one of the least liked, least understood and least considered aspects of teaching. After years of work, we have developed a grading system that is quite different from traditional and reformed approaches to grading and which meaningfully incorporates and integrates the collection of evidence, the evaluation of evidence, and the…

  14. Arizona Academic Standards, Grade 5

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains an updated academic standards of Arizona public schools for grade 5. The contents of this document include the following: (1) The Arts Standard 2006--Grade 5; (2) Comprehensive Health Education/Physical Activity Standards 1997--Essentials (Grades 4-8); (3) Foreign and Native Language Standards 1997--Foundations (Grades…

  15. Arizona Academic Standards, Grade 6

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains an updated academic standards of Arizona public schools for grade 6. The contents of this document include the following: (1) The Arts Standard 2006--Grade 6; (2) Comprehensive Health Education/Physical Activity Standards 1997--Essentials (Grades 4-8); (3) Foreign and Native Language Standards 1997--Essentials (Grades…

  16. Artificial muscles on heat

    NASA Astrophysics Data System (ADS)

    McKay, Thomas G.; Shin, Dong Ki; Percy, Steven; Knight, Chris; McGarry, Scott; Anderson, Iain A.

    2014-03-01

    Many devices and processes produce low grade waste heat. Some of these include combustion engines, electrical circuits, biological processes and industrial processes. To harvest this heat energy thermoelectric devices, using the Seebeck effect, are commonly used. However, these devices have limitations in efficiency, and usable voltage. This paper investigates the viability of a Stirling engine coupled to an artificial muscle energy harvester to efficiently convert heat energy into electrical energy. The results present the testing of the prototype generator which produced 200 μW when operating at 75°C. Pathways for improved performance are discussed which include optimising the electronic control of the artificial muscle, adjusting the mechanical properties of the artificial muscle to work optimally with the remainder of the system, good sealing, and tuning the resonance of the displacer to minimise the power required to drive it.

  17. Charm counting in b decays

    NASA Astrophysics Data System (ADS)

    Buskulic, D.; de Bonis, I.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Odier, P.; Pietrzyk, B.; Casado, M. P.; Chmeissani, M.; Crespo, J. M.; Delfino, M.; Efthymiopoulos, I.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Juste, A.; Martinez, M.; Orteu, S.; Padilla, C.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Teubert, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Girone, M.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Alemany, R.; Bazarko, A. O.; Bonvicini, G.; Bright-Thomas, P.; Cattaneo, M.; Cerutti, F.; Comas, P.; Coyle, P.; Drevermann, H.; Forty, R. W.; Frank, M.; Hagelberg, R.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Knobloch, J.; Lehraus, I.; Lutters, G.; Martin, E. B.; Mato, P.; Minten, A.; Miquel, R.; Mir, Ll. M.; Moneta, L.; Oest, T.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rensing, P.; Rizzo, G.; Rolandi, L.; Schlatter, D.; Schmelling, M.; Schmitt, M.; Schneider, O.; Tejessy, W.; Tomalin, I. R.; Venturi, A.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barrès, A.; Boyer, C.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.-M.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Zachariadou, K.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Rougé, A.; Rumpf, M.; Valassi, A.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Focardi, E.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Knowles, I. G.; Lynch, J. G.; O'Shea, V.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, F.; Thorn, S.; Turnbull, R. M.; Becker, U.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Schmidt, M.; Sommer, J.; Stenzel, H.; Tittel, K.; Werner, S.; Wunsch, M.; Abbaneo, D.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Stacey, A. M.; Williams, M. D.; Dissertori, G.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Sloan, T.; Williams, M. I.; Galla, A.; Giehl, I.; Greene, A. M.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Calvet, D.; Carr, J.; Diaconu, C.; Etienne, F.; Konstantinidis, N.; Payre, P.; Rousseau, D.; Talby, M.; Sadouki, A.; Thulasidas, M.; Trabelsi, K.; Aleppo, M.; Ragusa, F.; Bauer, C.; Berlich, R.; Blum, W.; Büscher, V.; Dietl, H.; Dydak, F.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; Denis, R. St.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Choi, Y.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Nikolic, I.; Park, H. J.; Schune, M.-H.; Simion, S.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Batignani, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; Dell'Orso, R.; Fantechi, R.; Ferrante, I.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciabà, A.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Vannini, C.; Verdini, P. G.; Blair, G. A.; Bryant, L. M.; Chambers, J. T.; Gao, Y.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Maley, P.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Johnson, R. P.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Boswell, R.; Brew, C. A. J.; Cartwright, S.; Combley, F.; Koksal, A.; Letho, M.; Newton, W. M.; Reeve, J.; Thompson, L. F.; Böhrer, A.; Brandt, S.; Cowan, G.; Grupen, C.; Minguet-Rodriguez, J.; Rivera, F.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; Della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Rothberg, J.; Wasserbaech, S.; Armstrong, S. R.; Elmer, P.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; González, S.; Grahl, J.; Greening, T. C.; Hayes, O. J.; Hu, H.; McNamara, P. A.; Nachtman, J. M.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, A. M.; Walsh, J.; Wu, Sau Lan; Wu, X.; Yamartino, J. M.; Zheng, M.; Zobernig, G.; Aleph Collaboration

    1996-02-01

    The inclusive production of charmed particles in Z → b overlineb decays has been measured from the yield of D0, D+, Ds+ and Λc+ decays in a sample of q overlineq events with high b purity collected with the ALEPH detector from 1992 to 1995. From these measurements, adding the charmonia production rate and an estimate of the charmed strange baryon contribution, the average number of charm quarks per b decay is determined to be nc = 1.230 ± 0.036 ± 0.038 ± 0.053, where the uncertainties are due to statistics, systematic effects and branching ratios, respectively.

  18. Glueball decay in holographic QCD

    SciTech Connect

    Hashimoto, Koji; Tan, C.-I; Terashima, Seiji

    2008-04-15

    Using holographic QCD based on D4-branes and D8-anti-D8-branes, we have computed couplings of glueballs to light mesons. We describe glueball decay by explicitly calculating its decay widths and branching ratios. Interestingly, while glueballs remain less well understood both theoretically and experimentally, our results are found to be consistent with the experimental data for the scalar glueball candidate f{sub 0}(1500). More generally, holographic QCD predicts that decay of any glueball to 4{pi}{sup 0} is suppressed, and that mixing of the lightest glueball with qq mesons is small.

  19. Decays of electron Bernstein waves near plasma edge

    SciTech Connect

    Xiang Nong; Cary, John R.

    2011-12-15

    Nonlinear wave-wave couplings near the upper hybrid resonance are studied via particle-in-cell simulations. It is found that the decay of an electron Bernstein wave (EBW) depends on the ratio of the incident frequency and electron cyclotron frequency. For ratios less than two, parametric decay into a lower hybrid wave (or an ion Bernstein wave) and EBWs at a lower frequency is observed. For ratios larger than two, the daughter waves could be an electron cyclotron quasi-mode and another EBW or an ion wave and EBW. For sufficiently high incident power, the former process may dominate. Because of the electron cyclotron quasi-mode, electrons can be strongly heated by nonlinear Landau damping. As a result, the bulk of the incident power can be absorbed near plasma edge at high power. The increase in number of decay channels with frequency implies that the allowable power into the plasma must decrease with frequency.

  20. Building Blocks of Tropical Diabatic Heating

    SciTech Connect

    Hagos, Samson M.

    2010-07-01

    Rotated EOF analyses are used to study the composition and variability of large-scale tropical diabatic heating profiles estimated from eight field campaigns. The results show that the profiles are composed of a pair of building blocks. These are the stratiform heating with peak heating near 400hpa and a cooling peak near 700hPa and convective heating with a heating maximum near 700hPa. Variations in the contributions of these building blocks account for the evolution of the large-scale heating profile. Instantaneous top (bottom) heavy large scale heating profiles associated with excess of stratiform (convective) heating evolve towards a stationary mean profile due to exponential decay of the excess stratiform (convective) heating.

  1. NUCLEAR POWER PLANT WASTE HEAT HORTICULTURE

    EPA Science Inventory

    The report gives results of a study of the feasibility of using low grade (70 degrees F) waste heat from the condenser cooling water of the Vermont Yaknee nuclear plant for commercial food enhancement. The study addressed the possible impact of laws on the use of waste heat from ...

  2. Radiative Leptonic B Decays

    SciTech Connect

    Chen, Edward Tann

    2007-01-01

    We present the results of a search for B+ meson decays into γℓ+v, where ℓ = e,μ. We use a sample of 232 million B$\\bar{B}$ meson pairs recorded at the Υ(4S) resonance with the BABAR detector at the PEP-II B factory. We measure a partial branching fraction Δβ in a restricted region of phase space that reduces the effect of theoretical uncertainties, requiring the lepton energy to be in the range 1.875 and 2.850 GeV, the photon energy to be in the range 0.45 and 2.35 GeV, and the cosine of the angle between the lepton and photon momenta to be less than -0.36, with all quantities computed in the Υ(4S) center-of-mass frame. We find Δβ(B+ → γℓ+v) = (-0.31.5+1.3(statistical) -0.6+0.6(systematic) ± 0.1(theoretical)) x 10-6, under the assumption of lepton universality. Interpreted as a 90% confidence-level Bayesian upper limit, the result corresponds to 1.7 x 10-6 for a prior at in amplitude, and 2.3 x 10-6 for a prior at in branching fraction.

  3. Job Grading Standard for Instrument Maker, WG-4712.

    ERIC Educational Resources Information Center

    Civil Service Commission, Washington, DC. Bureau of Policies and Standards.

    The standard is used to grade all nonsupervisory jobs involved inplanning and fabricating complex research and prototype instruments, made from a variety of materials, which are used to detect, measure, record, and regulate heat, pressure, speed, vibration, sound, illumination, biomedical phenomena, and other areas of interest to scientific,…

  4. Autothermal gasification of low-grade fuels in fluidized bed

    NASA Astrophysics Data System (ADS)

    Belyaev, A. A.

    2009-01-01

    Autothermal gasification of high-ash floatation wastes of Grade Zh Kuzbass coal and low-ash fuel in a suspended-spouted (fluidized) bed at atmospheric pressure is investigated, and a comparison is presented of experimental results that indicate that the ash content of fuels has only slight influence on the generator gas heating value.

  5. Weather. Third Grade. Revised. Anchorage School District Elementary Science Program.

    ERIC Educational Resources Information Center

    Defendorf, Jean, Ed.

    This resource book introduces third-grade children to the environment by studying the weather and its effects. Lessons are provided including: (1) constructing a weather diary; (2) thermometers; (3) clouds; (4) barometric pressure; (5) wind vanes; (6) heating and cooling air; and (7) analyzing weather data. Each lesson includes a listing of…

  6. The decay of hot nuclei

    SciTech Connect

    Moretto, L.G.; Wozniak, G.J.

    1988-11-01

    The formation of hot compound nuclei in intermediate-energy heavy ion reactions is discussed. The statistical decay of such compound nuclei is responsible for the abundant emission of complex fragments and high energy gamma rays. 43 refs., 23 figs.

  7. Questions Students Ask: Beta Decay.

    ERIC Educational Resources Information Center

    Koss, Jordan; Hartt, Kenneth

    1988-01-01

    Answers a student's question about the emission of a positron from a nucleus. Discusses the problem from the aspects of the uncertainty principle, beta decay, the Fermi Theory, and modern physics. (YP)

  8. The Search for Proton Decay.

    ERIC Educational Resources Information Center

    Marshak, Marvin L.

    1984-01-01

    Provides the rationale for and examples of experiments designed to test the stability of protons and bound neutrons. Also considers the unification question, cosmological implications, current and future detectors, and current status of knowledge on proton decay. (JN)

  9. Overview of rare K decays

    SciTech Connect

    Littenberg, L.

    1995-05-01

    The status and future prospects of searches for and studies of forbidden and highly suppressed K decays are reviewed. Here the author discusses three areas of recent activity in rare K decay. These are lepton-flavor violating decays, which are entirely forbidden in the Standard Model, K{sub S} {yields} {pi}{sup +}{pi}{sup {minus}}{pi}{sup 0}, which is of interest from the point of view of CP-violation, and `one loop` decays of the form K{sup 0,{+-}} {yields} ({pi}{sup 0,{+-}})l{bar l}, that can throw light on Standard Model CP-violation and determine parameters such as V{sub td}.

  10. CP violation in K decays

    SciTech Connect

    Gilman, F.J.

    1989-05-01

    Recent theoretical and experimental progress on the manifestation of CP violation in K decays, and toward understanding whether CP violation originates in a phase, or phases, in the weak mixing matrix of quarks is reviewed. 23 refs., 10 figs.

  11. A comparative study of radiation effects in medical-grade polymers: UHMWPE, PCU and PEEK

    NASA Astrophysics Data System (ADS)

    Jahan, Muhammad S.; Walters, Benjamin M.; Riahinasab, Tayebeh; Gnawali, Rudra; Adhikari, Dipendra; Trieu, Hai

    2016-01-01

    In this study, three medical-grade polymers, ultra-high molecular weight polyethylene (UHMWPE), polycarbonate urethane (PCU) and poly (ether ether ketone) PEEK, were tested immediately after x-irradiation. The primary purpose of this study was to provide a qualitative comparison of the radiation-sensitivity of these polymers. To evaluate radiation-induced defects or trapped charges, radiation dosimetry method, known as thermally stimulated luminescence (TSL) or thermoluminescence (TL), was employed, and for free radical comparison, electron spin resonance (ESR) was used. When these polymers were x-irradiated at room temperature and subsequently heated, broad luminescence was detected as a function of temperature (known as a glow curve) in the temperature region of 75 °C to 250 °C. In particular, TSL of PCU exhibited glow peaks near 140 °C and 225 °C, that of PEEK near 100 °C and 150 °C, and of UHMWPE near 100 °C and 140 °C. In each case, totalTSL was found to increase as a function of x-ray exposure, suggesting the production of radiation-induced species in the respective polymer matrix. Compared to PCU or PEEK, UHMWPE was found to form more than one order of magnitude of free radicals per unit mass per unit x-ray exposure. In two hours in air at room temperature after irradiation, UHMWPE lost 42% of its initial radical concentration, while PCU lost 75%. X-ray induced PEEK radicals (peroxy/phenoxy) decayed in about one week. Unlike UHMWPE or PCU, non-irradiated (as-received) PEEK was found to contain residual radicals. In UHMWPE, primary radicals reportedly decay to oxygen-centered polyenyl radicals in about three months. In all the results did find significant radical formation via ESR and supporting radiation sensitivity measurements via TSL, warranting further investigation into the effects of radiation on PEEK and PCU.

  12. Proton decay and nuclear dynamics

    SciTech Connect

    Alvioli, M.; Strikman, M.; Benhar, O.; Ericson, M.

    2010-04-15

    The kinematics of the decay of a bound proton is governed by the proton spectral function. We evaluate this quantity in {sup 16}O using the information from nuclear physics experiments. It also includes a correlated part. The reliability of this evaluation is sufficient to open the possibility of correlated cuts in the missing mass and momentum variables to identify the decay events from the bound protons with a possible increase of the signal-to-noise ratio.

  13. Thermal corrections to Electroweak Decays

    NASA Astrophysics Data System (ADS)

    Masood, Samina

    2016-03-01

    We study the electroweak processes at finite temperatures. This includes the decay rates of electroweak gauge bosons and beta decays. Major thermal corrections come from QED type radiative corrections. Heavy mass of the electroweak gauge bosons helps to suppress the radiative corrections due to the electroweak gauge boson loops. Therefore, dominant thermal corrections are due to the photon loops. We also discuss the relevance of our results to astrophysics and cosmology.

  14. Semileptonic B-Meson Decays

    SciTech Connect

    Volk, Alexei; /Dresden, Tech. U.

    2010-08-26

    The study of the semileptonic B-meson decays is the most accessible and cleanest way to determine the CKM matrix elements |V{sub cb}| and V{sub ub}. These decays also provide experimental access to study the QCD form-factors, heavy quark masses, and HQE parameters. The theoretical description of semileptonic B-meson decays at the parton level is very simple because there is no interaction between leptonic and hadronic currents. At the hadron level one needs to introduce corrections due to the strong interaction between quarks. Especially in the description of the inclusive B-meson decays the motion of the b-quark inside the B-meson plays a crucial role. All these effects are described in the frameworks of Heavy Quark Effective Theory (HQET) and Lattice QCD (LQCD). We give an overview about results of studies of semileptonic B-meson decays collected with the BABAR and Belle detectors at the PEP-II and the KEKB e{sup +}e{sup -}-storage rings. We present recent results on hadronic moments measured in inclusive B {yields} X{sub c}lv and B {yields} X{sub u}lv decays and extracted heavy quark masses m{sub b} and m{sub c} and dominant non-perturbative Heavy Quark Expansion (HQE) parameters. We also report the measurements of the CKM matrix elements |V{sub cb}| and |V{sub ub}| in inclusive and in exclusive semileptonic B-meson decays. We describe the studies of the form-factor parameters for the decay B{sup 0} {yields} D*{sup -}l{sup +}v and present the measurement of the B{sup 0} {yields} {pi}{sup -}l{sup +}v form-factor shape.

  15. 7 CFR 810.106 - Grade designations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD ADMINISTRATION (FEDERAL GRAIN INSPECTION SERVICE), DEPARTMENT OF AGRICULTURE OFFICIAL UNITED STATES STANDARDS FOR GRAIN General Provisions Grades, Grade Requirements, and Grade Designations § 810.106 Grade...

  16. 7 CFR 810.106 - Grade designations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD ADMINISTRATION (FEDERAL GRAIN INSPECTION SERVICE), DEPARTMENT OF AGRICULTURE OFFICIAL UNITED STATES STANDARDS FOR GRAIN General Provisions Grades, Grade Requirements, and Grade Designations § 810.106 Grade...

  17. 7 CFR 810.106 - Grade designations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD ADMINISTRATION (FEDERAL GRAIN INSPECTION SERVICE), DEPARTMENT OF AGRICULTURE OFFICIAL UNITED STATES STANDARDS FOR GRAIN General Provisions Grades, Grade Requirements, and Grade Designations § 810.106 Grade...

  18. Physical limits on steam generation by radioactive decay heat

    SciTech Connect

    Chesnut, D.A.

    1991-12-01

    This report briefly discusses the possibilities that flood water contacting the hot radioactive waste and rock at Yucca Mountain could produce enough steam to lift the top of the mountain off the repository.

  19. Grading the teacher

    NASA Astrophysics Data System (ADS)

    Swartz, Clifford E.

    2000-04-01

    Several fads ago there was a movement to grade teachers in terms of their competency — competency-based testing. Everyone knows that there are good teachers and there are bad teachers. The trouble is, it's hard to define the categories. It's like the Supreme Court justice who couldn't define pornography, but knew it when he saw it. In New York State, prospective teachers must take tests in both pedagogy and subject material. That seems reasonable. There ought to be some minimum standards, so I thought that I would try my hand at setting up such requirements.

  20. Reionization and dark matter decay

    NASA Astrophysics Data System (ADS)

    Oldengott, Isabel M.; Boriero, Daniel; Schwarz, Dominik J.

    2016-08-01

    Cosmic reionization and dark matter decay can impact observations of the cosmic microwave sky in a similar way. A simultaneous study of both effects is required to constrain unstable dark matter from cosmic microwave background observations. We compare two reionization models with and without dark matter decay. We find that a reionization model that fits also data from quasars and star forming galaxies results in tighter constraints on the reionization optical depth τreio, but weaker constraints on the spectral index ns than the conventional parametrization. We use the Planck 2015 data to constrain the effective decay rate of dark matter to Γeff < 2.9 × 10‑25/s at 95% C.L. This limit is robust and model independent. It holds for any type of decaying dark matter and it depends only weakly on the chosen parametrization of astrophysical reionization. For light dark matter particles that decay exclusively into electromagnetic components this implies a limit of Γ < 5.3 × 10‑26/s at 95% C.L. Specifying the decay channels, we apply our result to the case of keV-mass sterile neutrinos as dark matter candidates and obtain constraints on their mixing angle and mass, which are comparable to the ones from the diffuse X-ray background.

  1. Observations of HF backscatter decay rates from HAARP generated FAI

    NASA Astrophysics Data System (ADS)

    Bristow, William; Hysell, David

    2016-07-01

    Suitable experiments at the High-frequency Active Auroral Research Program (HAARP) facilities in Gakona, Alaska, create a region of ionospheric Field-Aligned Irregularities (FAI) that produces strong radar backscatter observed by the SuperDARN radar on Kodiak Island, Alaska. Creation of FAI in HF ionospheric modification experiments has been studied by a number of authors who have developed a rich theoretical background. The decay of the irregularities, however, has not been so widely studied yet it has the potential for providing estimates of the parameters of natural irregularity diffusion, which are difficult measure by other means. Hysell, et al. [1996] demonstrated using the decay of radar scatter above the Sura heating facility to estimate irregularity diffusion. A large database of radar backscatter from HAARP generated FAI has been collected over the years. Experiments often cycled the heater power on and off in a way that allowed estimates of the FAI decay rate. The database has been examined to extract decay time estimates and diffusion rates over a range of ionospheric conditions. This presentation will summarize the database and the estimated diffusion rates, and will discuss the potential for targeted experiments for aeronomy measurements. Hysell, D. L., M. C. Kelley, Y. M. Yampolski, V. S. Beley, A. V. Koloskov, P. V. Ponomarenko, and O. F. Tyrnov, HF radar observations of decaying artificial field aligned irregularities, J. Geophys. Res. , 101, 26,981, 1996.

  2. Triton's Global Heat Budget.

    PubMed

    Brown, R H; Johnson, T V; Goguen, J D; Schubert, G; Ross, M N

    1991-03-22

    Internal heat flow from radioactive decay in Triton's interior along with absorbed thermal energy from Neptune total 5 to 20 percent of the insolation absorbed by Triton, thus comprising a significant fraction of Triton's surface energy balance. These additional energy inputs can raise Triton's surface temperature between approximately 0.5 and 1.5 K above that possible with absorbed sunlight alone, resulting in an increase of about a factor of approximately 1.5 to 2.5 in Triton's basal atmospheric pressure. If Triton's internal heat flow is concentrated in some areas, as is likely, local effects such as enhanced sublimation with subsequent modification of albedo could be quite large. Furthermore, indications of recent global albedo change on Triton suggest that Triton's surface temperature and pressure may not now be in steady state, further suggesting that atmospheric pressure on Triton was as much as ten times higher in the recent past. PMID:17779439

  3. Triton's global heat budget

    SciTech Connect

    Brown, R.H.; Johnson, T.V.; Goguen, J.D. ); Schubert, G. ); Ross, M.N. )

    1991-03-22

    Internal heat flow from radioactive decay in Triton's interior along with absorbed thermal energy from Neptune total 5 to 20% of the insolation absorbed by Triton, thus comprising a significant fraction of Triton's surface energy balance. These additional energy inputs can raise Triton's surface temperature between {approximately}0.5 and 1.5 K above that possible with adsorbed sunlight alone, resulting in an increase of about a factor of {approximately}1.5 to 2.5 in Triton's basal atmospheric pressure. If Triton's internal heat flow is concentrated in some areas, as is likely, local effects such as enhanced sublimation with subsequent modification of albedo could be quite large. Furthermore, indications of recent global albedo change on Triton suggest that Triton's surface temperature and pressure may not now be in steady state, further suggesting that atmospheric pressure on Triton was as much as ten times higher in the recent past.

  4. Triton's global heat budget

    NASA Technical Reports Server (NTRS)

    Brown, R. H.; Johnson, T. V.; Goguen, J. D.; Schubert, G.; Ross, M. N.

    1991-01-01

    Internal heat flow from radioactive decay in Triton's interior along with absorbed thermal energy from Neptune total 5 to 20 percent of the isolation absorbed by Triton, thus comprising a significant fraction of Triton's surface energy balance. These additional energy inputs can raise Triton's surface temperature between about 0.5 and 1.5 K above that possible with absorbed sunlight alone, resulting in an increase of about a factor of about 1.5 to 2.5 in Triton's basal atmospheric pressure. If Triton's internal heat flow is concentrated in some areas, as is likely, local effects such as enhanced sublimation with subsequent modification of albedo could be quite large. Furthermore, indications of recent global albedo change on Triton suggest that Triton's surface temperature and pressure may not now be in steady state, further suggesting that atmospheric pressure on Triton was as much as ten times higher in the recent past.

  5. Pollination biology of basal angiosperms (ANITA grade).

    PubMed

    Thien, Leonard B; Bernhardt, Peter; Devall, Margaret S; Chen, Zhi-Duan; Luo, Yi-Bo; Fan, Jian-Hua; Yuan, Liang-Chen; Williams, Joseph H

    2009-01-01

    The first three branches of the angiosperm phylogenetic tree consist of eight families with ∼201 species of plants (the ANITA grade). The oldest flower fossil for the group is dated to the Early Cretaceous (115-125 Mya) and identified to the Nymphaeales. The flowers of extant plants in the ANITA grade are small, and pollen is the edible reward (rarely nectar or starch bodies). Unlike many gymnosperms that secrete "pollination drops," ANITA-grade members examined thus far have a dry-type stigma. Copious secretions of stigmatic fluid are restricted to the Nymphaeales, but this is not nectar. Floral odors, floral thermogenesis (a resource), and colored tepals attract insects in deceit-based pollination syndromes throughout the first three branches of the phylogenetic tree. Self-incompatibility and an extragynoecial compitum occur in some species in the Austrobaileyales. Flies are primary pollinators in six families (10 genera). Beetles are pollinators in five families varying in importance as primary (exclusive) to secondary vectors of pollen. Bees are major pollinators only in the Nymphaeaceae. It is hypothesized that large flowers in Nymphaeaceae are the result of the interaction of heat, floral odors, and colored tepals to trap insects to increase fitness. PMID:21628182

  6. Results of fission products β decay properties measurement performed with a total absorption spectrometer

    NASA Astrophysics Data System (ADS)

    Zakari-Issoufou, A.-A.; Porta, A.; Fallot, M.; Algora, A.; Tain, J. L.; Valencia, E.; Rice, S.; Agramunt, J.; Äystö, J.; Bowry, M.; Bui, V. M.; Caballero-Folch, R.; Cano-Ott, D.; Eloma, V.; Estévez, E.; Farrelly, G. F.; Garcia, A.; Gelletly, W.; Gomez-Hornillos, M. B.; Gorlychev, V.; Hakala, J.; Jokinen, A.; Jordan, M. D.; Kankainen, A.; Kondev, F. G.; Martinez, T.; Mendoza, E.; Molina, F.; Moore, I.; Perez, A.; Podolyak, Zs.; Penttilä, H.; Regan, P. H.; Rissanen, J.; Rubio, B.; Weber, C.

    2014-03-01

    β-decay properties of fission products are very important for applied reactor physics, for instance to estimate the decay heat released immediately after the reactor shutdown and to estimate the bar ν flux emitted. An accurate estimation of the decay heat and the bar ν emitted flux from reactors, are necessary for purposes such as reactors operation safety and non-proliferation. In order to improve the precision in the prediction for these quantities, the bias due to the Pandemonium effect affecting some important fission product data has to be corrected. New measurements of fission products β-decay, not sensitive to this effect, have been performed with a Total Absorption Spectrometer (TAS) at the JYFL facility of Jyväskylä. An overview of the TAS technique and first results from the 2009 campaign will be presented.

  7. Unsolved problems in hadronic charm decay

    SciTech Connect

    Browder, T.E.

    1989-08-01

    This paper describes several outstanding problems in the study of hadronic decays of charmed mesons where further experimental work and theoretical understanding is needed. Four topics are stressed: double Cabibbo suppressed decays (DCSD) of D/sup +/ mesons, hadronic D/sub s/ decays, weak hadronic quasi-two-body decays to pairs of vector mesons, and penguin decays of D mesons. 24 refs., 10 figs., 5 tabs.

  8. Decay curve study in a standard electron capture decay

    SciTech Connect

    Nishimura, D.; Fukuda, M.; Kisamori, K.; Kuwada, Y.; Makisaka, K.; Matsumiya, R.; Matsuta, K.; Mihara, M.; Takagi, A.; Yokoyama, R.; Izumikawa, T.; Ohtsubo, T.; Suzuki, T.; Yamaguchi, T.

    2010-05-12

    We have searched for a time-modulated decay in a standard electron capture experiment for {sup 140}Pr, in order to confirm a report from GSI, where an oscillatory decay has been observed for hydrogen-like {sup 140}Pr and {sup 142}Pm ions in the cooler storage ring. {sup 140}Pr has been produced with the {sup 140}Ce(p, n) reaction by a pulsed proton beam accelerated from the Van de Graaff accelerator at Osaka University. Resultant time dependence of the K{sub a}lpha and K{sub b}eta X-ray intensities from the daughter shows no oscillatory behavior.

  9. Mechanics of Graded Wrinkles

    NASA Astrophysics Data System (ADS)

    Raayai-Ardakani, Shabnam; Boyce, Mary

    2013-03-01

    Shark skin is known for its anti-fouling and self-cleaning properties. In attempts to mimic this pattern for getting similar properties, different surface patterns such as Sharklet and wrinkles have been previously introduced. Wrinkled patterns have gained importance in applications such as microfluidics, wetting and adhesion. Through buckling of a thin film of stiff material on a substrate of softer material, and maintaining symmetric geometries, ordered wrinkled patterns can be created. However, it can be shown that using the same principle, by changing the geometry of the surface, the dimensions of the wrinkles can be altered. This alteration turns ordered wrinkles into graded wrinkles which have more resemblance to shark skin than the ordered wrinkles, maintaining the same wave length while each wave having different amplitude. Here using finite element models, experiments and analytical solutions, the relations between different geometries and the resulting patterns were investigated.

  10. Cheap Heat.

    ERIC Educational Resources Information Center

    Switzer, Terry G.

    1986-01-01

    Describes an activity from the ninth-grade physical science program at the Energy Management Center, the outdoor science and energy education center for students in Pasco County, Florida. The activity focuses on making an effective solar collector. (JN)

  11. Grade 10 to Grade 12 Mathematics Resources: Annotated Bibliography.

    ERIC Educational Resources Information Center

    Western Canadian Protocol for Collaboration in Basic Education, Edmonton (Alberta).

    This annotated bibliography identifies English language resources endorsed by all Western Canadian Protocol (WCP) jurisdictions implementing The Common Curriculum Framework for K-12 Mathematics Grade 10 to Grade 12. Resources in this annotated bibliography were selected through a collaborative review process based on their high level of fidelity…

  12. Mathematics, Grade 2, Grade 3, Scope and Sequence.

    ERIC Educational Resources Information Center

    New York City Board of Education, Brooklyn, NY. Bureau of Curriculum Development.

    This publication is designed to extend and strengthen the computational skills and mathematical understandings of children in Grades 2 and 3. It presents an overall scope and detailed sequence for implementation by teachers and supervisors, based on the modern program introduced in pre-kindergarten, kindergarten and first grade classes. The scope…

  13. Mathematics, Grade 4, Grade 5, Scope and Sequence.

    ERIC Educational Resources Information Center

    New York City Board of Education, Brooklyn, NY. Bureau of Curriculum Development.

    Presented is the scope and sequence of mathematics for Grades 4 and 5. It is based on the program which is introduced in prekindergarten through Grade 3 and is designed to extend and strengthen the computational skills and mathematical understanding of children. The units described are organized around four main themes--sets, number, and…

  14. Prediction of Grade of Dropout from 3rd Grade Data.

    ERIC Educational Resources Information Center

    Lloyd, Dee Norman; Bleach, Gail

    Measures of background characteristics, school performance, and test achievement were analyzed for four race-by-sex samples of third graders who were known to have later become high school dropouts. In each sample, age in the third grade, course marks, and standardized achievement scores were found to be significantly related to the grade in which…

  15. Heat Stress

    MedlinePlus

    ... Stress Learn some tips to protect workers including: acclimatization, rest breaks, and fluid recommendations. NIOSH Workplace Solution: ... Blog: Adjusting to Work in the Heat: Why Acclimatization Matters The natural adaptation to the heat takes ...

  16. Heating Safety

    MedlinePlus

    ... from heating equipment, such as the furnace, fireplace, wood stove, or portable heater. • Only use heating equipment ... into the room and burn only dry, seasoned wood. Allow ashes to cool before disposing in a ...

  17. The search for proton decay

    SciTech Connect

    Haines, T.; Kaneyuki, K.; McGrew, C.; Mohapatra, R.; Peterson, E.; Cline, D.B.

    1994-12-31

    The conservation of the quantum number called baryon number, like lepton (or family) number, is an empirical fact even though there are very good reasons to expect otherwise. Experimentalists have been searching for baryon number violating decays of the proton and neutron for decades now without success. Theorists have evolved deep understanding of the relationship between the natural forces in the development of various Grand Unified Theories (GUTs) that nearly universally predict baryon number violating proton decay, or related phenomena like n-{bar n} oscillations. With this in mind, the Proton Decay Working Group reviewed the current experimental and theoretical status of the search for baryon number violation with an eye to the advancement in the next decade.

  18. Tunneling decay of false kinks

    NASA Astrophysics Data System (ADS)

    Dupuis, Éric; Gobeil, Yan; MacKenzie, Richard; Marleau, Luc; Paranjape, M. B.; Ung, Yvan

    2015-07-01

    We consider the decay of "false kinks," that is, kinks formed in a scalar field theory with a pair of degenerate symmetry-breaking false vacua in 1 +1 dimensions. The true vacuum is symmetric. A second scalar field and a peculiar potential are added in order for the kink to be classically stable. We find an expression for the decay rate of a false kink. As with any tunneling event, the rate is proportional to exp (-SE) where SE is the Euclidean action of the bounce describing the tunneling event. This factor varies wildly depending on the parameters of the model. Of interest is the fact that for certain parameters SE can get arbitrarily small, implying that the kink is only barely stable. Thus, while the false vacuum itself may be very long-lived, the presence of kinks can give rise to rapid vacuum decay.

  19. Observable signatures of inflaton decays

    SciTech Connect

    Battefeld, Diana; Battefeld, Thorsten; Giblin, John T. Jr.; Pease, Evan K. E-mail: tbattefe@astro.physik.uni-goettingen.de E-mail: peasee@kenyon.edu

    2011-02-01

    We numerically compute features in the power-spectrum that originate from the decay of fields during inflation. Using a simple, phenomenological, multi-field setup, we increase the number of fields from a few to thousands. Whenever a field decays, its associated potential energy is transferred into radiation, causing a jump in the equation of state parameter and mode mixing at the perturbed level. We observe discrete steps in the power-spectrum if the number of fields is low, in agreement with analytic arguments in the literature. These features become increasingly smeared out once many fields decay within a given Hubble time. In this regime we confirm the validity of the analytic approach to staggered inflation, which is based on a coarse-graining procedure. Our numerical approach bridges the aforementioned analytic treatments, and can be used in more complicated scenarios.

  20. Free radical decay in adamantane

    SciTech Connect

    Tegowski, A.T.; Pratt, D.W.

    1984-01-11

    Kinetic electron paramagnetic resonance (EPR) techniques have been used to characterize the decay behavior of the ''stable'' free radical 2-cyclohexanonyl in the plastic crystal phase f an adamantane matrix over the temperature range 257-313 K. Typical plots of the EPR signal intensity as a function of time are biexponential in nature, suggesting the existence of at least two channels for free radical decay. The activation parameters for both processes have been measured in both protonated and deuterated samples. A comparison of these results with those in other systems suggests that the host does, as expected, considerably reduce the pre-exponential factors for decay of the radical by bimolecular processes but has relatively little influence on the corresponding activation energies. 3 figures.

  1. EC decay of 244Bk

    NASA Astrophysics Data System (ADS)

    Sodaye, Suparna; Tripathi, R.; Sudarshan, K.; Sharma, S. K.; Pujari, P. K.; Palit, R.; Mukhopadhyay, S.

    2014-12-01

    Berkelium isotopes have been produced in 11B-induced reaction on 238U. The EC decay of 244Bk → 244Cm has been studied by carrying out the single and coincidence measurements of the γ-rays emitted during the de-excitation of the 244Cm levels. Radiochemical separations have been carried out to minimize the contribution from the fission products and target. The new half-life of 244Bk is obtained as 5.02 ± 0.03 h, which is close to the theoretically calculated value. The relative intensities of the decay γ-rays have been re-evaluated. Based on the coincidence measurements, a tentative partial level scheme for 244Bk → 244Cm decay has been proposed.

  2. Heavy quark spectroscopy and decay

    SciTech Connect

    Schindler, R.H.

    1987-01-01

    The understanding of q anti q systems containing heavy, charmed, and bottom quarks has progressed rapidly in recent years, through steady improvements in experimental techniques for production and detection of their decays. These lectures are meant to be an experimentalist's review of the subject. In the first of two lectures, the existing data on the spectroscopy of the bound c anti c and b anti b systems will be discussed. Emphasis is placed on comparisons with the theoretical models. The second lecture covers the rapidly changing subject of the decays of heavy mesons (c anti q and b anti q), and their excited states. In combination, the spectroscopy and decays of heavy quarks are shown to provide interesting insights into both the strong and electroweak interactions of the heavy quarks. 103 refs., 39 figs.

  3. General Purpose Heat Source Simulator

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.

    2008-01-01

    The General Purpose Heat Source (GPHS) project seeks to combine the development of an electrically heated, single GPHS module simulator with the evaluation of potential nuclear surface power systems. The simulator is designed to match the form, fit, and function of actual GPHS modules which normally generate heat through the radioactive decay of Pu238. The use of electrically heated modules rather than modules containing Pu238 facilitates the testing of the subsystems and systems without sacrificing the quantity and quality of the test data gathered. Current GPHS activities are centered on developing robust heater designs with sizes and weights which closely match those of actual Pu238 fueled GPHS blocks. Designs are being pursued which will allow operation up to 1100 C.

  4. Heat exchanger

    DOEpatents

    Daman, Ernest L.; McCallister, Robert A.

    1979-01-01

    A heat exchanger is provided having first and second fluid chambers for passing primary and secondary fluids. The chambers are spaced apart and have heat pipes extending from inside one chamber to inside the other chamber. A third chamber is provided for passing a purge fluid, and the heat pipe portion between the first and second chambers lies within the third chamber.

  5. The study of rare decays

    NASA Astrophysics Data System (ADS)

    Ju, Wan-Li; Wang, Guo-Li; Fu, Hui-Feng; Wang, Tian-Hong; Jiang, Yue

    2014-04-01

    In this paper, we study rare decays within the Standard Model. The penguin, box, annihilation, color-favored cascade and color-suppressed cascade contributions are included. Based on our calculation, the annihilation and color-favored cascade diagrams play important roles in the differential branching fractions, forward-backward asymmetries, longitudinal polarizations of the final vector mesons and leptonic longitudinal polarization asymmetries. More importantly, color-favored cascade decays largely enhance the resonance cascade contributions. To avoid the resonance cascade contribution pollution, new cutting regions are put forward.

  6. Laser-Assisted Muon Decay

    SciTech Connect

    Liu Aihua; Li Shumin; Berakdar, Jamal

    2007-06-22

    We show theoretically that the muon lifetime can be changed dramatically by embedding the decaying muon in a strong linearly polarized laser field. Evaluating the S-matrix elements taking all electronic multiphoton processes into account we find that a CO{sub 2} laser with an electric field amplitude of 10{sup 6} V cm{sup -1} results in an order of magnitude shorter lifetime of the muon. We also analyze the dependencies of the decay rate on the laser frequency and intensity.

  7. Online Data Monitoring for the CUORE Neutrinoless Double-beta Decay Experiment

    NASA Astrophysics Data System (ADS)

    Feintzeig, Jacob; Cuore Collaboration

    2015-10-01

    The Cryogenic Underground Observatory for Rare Events (CUORE) is an upcoming bolometric experiment that will search for neutrinoless double-beta decay at Gran Sasso, Italy. Crystals of tellurium dioxide are instrumented with neutron transmutation doped (NTD) thermistors to observe the heat pulse caused by a double beta decay event. Currently under construction, CUORE will contain 988 independent bolometers. The CUORE-0 detector, consisting of the first 52 bolometers, took data from 2013-2015. After briefly reviewing results from a neutrinoless double-beta decay search with CUORE-0, I will outline recent work to improve data analysis and online data quality monitoring for the upcoming CUORE detector.

  8. Decay Data Evaluation Project (DDEP): evaluation of the main 233Pa decay characteristics.

    PubMed

    Chechev, Valery P; Kuzmenko, Nikolay K

    2006-01-01

    The results of a decay data evaluation are presented for 233Pa (beta-) decay to nuclear levels in 233U. These evaluated data have been obtained within the Decay Data Evaluation Project using information published up to 2005. PMID:16574422

  9. Elementary Science Curriculum, Grade 4.

    ERIC Educational Resources Information Center

    Stoneham Public Schools, MA.

    This is one of a set of curriculum guides for the Stoneham Elementary School Science Program (see SE 012 153 - SE 012 158). Each guide contains a chart illustrating the scope and sequence of the physical, life, and earth sciences introduced at each grade level. For each of the topics introduced at this grade level an overview of the topic, a list…

  10. Elementary Science Curriculum, Grade 1.

    ERIC Educational Resources Information Center

    Stoneham Public Schools, MA.

    This is one of a set of curriculum guides for the Stoneham Elementary School Science Program (see SE 012 153 - SE 012 158). Each guide contains a chart illustrating the scope and sequence of the physical, life, and earth sciences introduced at each grade level. For each of the topics introduced at this grade level, an overview of the topic, a list…

  11. Learning-Centered Grading Practices

    ERIC Educational Resources Information Center

    Campbell, Conni

    2012-01-01

    The research on grading practice over two decades is clear: grading practices are firmly held beliefs that are near and dear to the teaching professional. At a time when government, business and industry, and the general public are calling for an accountability of student knowledge and abilities, classroom assessment practices could be…

  12. Grading Practices: The Third Rail

    ERIC Educational Resources Information Center

    Erickson, Jeffrey A.

    2010-01-01

    Although Social Security funds are in decline and no solution is evident, few politicians have the temerity to try to change the system. Why? Because Social Security is the third rail in politics: if one touches it, he or she will die. The field of education has an issue that is equally as lethal: grading. Grading is one of the most private…

  13. Graded geometry and Poisson reduction

    SciTech Connect

    Cattaneo, A. S.; Zambon, M.

    2009-02-02

    The main result extends the Marsden-Ratiu reduction theorem in Poisson geometry, and is proven by means of graded geometry. In this note we provide the background material about graded geometry necessary for the proof. Further, we provide an alternative algebraic proof for the main result.

  14. Grading Exceptional and Struggling Learners

    ERIC Educational Resources Information Center

    Jung, Lee Ann; Guskey, Thomas R.

    2011-01-01

    How can you ensure that you are grading your exceptional students fairly? Teachers receive very little guidance for grading students with disabilities, English learners, and those receiving services through a response-to-intervention (RTI) process. This practitioner-friendly book provides teachers and administrators with an effective framework for…

  15. Elementary Science Curriculum, Grade 2.

    ERIC Educational Resources Information Center

    Stoneham Public Schools, MA.

    This is one of a set of curriculum guides for the Stoneham Elementary School Science Program (see SE 012 153 - SE 012 158). Each guide contains a chart illustrating the scope and sequence of the physical, life, and earth sciences introduced at each grade level. For each of the topics introduced at this grade level, an overview of the topic, a list…

  16. Elementary Science Curriculum, Grade 6.

    ERIC Educational Resources Information Center

    Stoneham Public Schools, MA.

    This is one of a set of curriculum guides for the Stoneham Elementary School Science Program (see SE 012 153 - SE 012 158). Each guide contains a chart illustrating the scope and sequence of the physical, life, and earth sciences introduced at each grade level. For each of the topics introduced at this grade level an overview of the topic, a list…

  17. First Grade Pre-Screening

    ERIC Educational Resources Information Center

    Center for Innovation in Assessment (NJ1), 2013

    2013-01-01

    The First Grade Pre-Screening is designed to be used at the start of the first grade school year so that teachers can obtain information about their incoming students. This information is intended to give teachers insight about what math and reading skills a student may or may not have at the beginning of the year. The information can aid teachers…

  18. Alternatives to Grading Student Writing.

    ERIC Educational Resources Information Center

    Tchudi, Stephen, Ed.

    The result of an investigation into the grading writing by the National Council of Teachers of English Committee on Alternatives to Grading Student Writing, this collection of essays offers the writing teacher several innovative and interesting options. Following an introduction by the editor (chair of the Committee), in which he delineates the…

  19. Retention in Grade: Lethal Lessons?

    ERIC Educational Resources Information Center

    Sherwood, Charles

    Despite a growing trend toward retention in grade of low-achieving students and apparent public support for the practice, many educators and psychologists disagree with the perception that flunking is an appropriate response to poor academic performance. Research reported in the past two decades indicates that grade-level retention produces little…

  20. Reading Abilities and College Grades

    ERIC Educational Resources Information Center

    Pedrini, D. T.; Pedrini, Bonnie C.

    1975-01-01

    The importance of reading in a course (content, evaluation, etc.) needs to be considered. This research involved 120 college students and compared the Revised Nelson-Denny reading scores (vocabulary, comprehension, rate) and a course grade. Questionnaire responses were also received. Vocabulary predicted about 35 percent of the grade variance.…

  1. Starting the Conversation about Grading

    ERIC Educational Resources Information Center

    Brookhart, Susan M.

    2011-01-01

    As they attempt to make the transition to standards-based grading, many schools go off track or get swamped by side issues, writes Brookhart. They waste energy having hard discussions about grading practice details that, by themselves, cannot accomplish real reform. Instead, schools should focus discussion on major questions: What meaning do we…

  2. Upgrading Metallurgical-Grade Silicon

    NASA Technical Reports Server (NTRS)

    Woerner, L. M.; Moore, E. B.

    1985-01-01

    Closed-loop process produces semiconductor-grade silicon. Metallurgical-grade silicon converted to ultrapure silicon by reacting with hydrogen and silicon tetrahalide to form trihalosilane, purifying this intermediate and again decomposing to high purity silicon in third stage. Heterogeneously and homogeneously nucleated polycrystalline silicon used in semiconductor device applications and in silicon photovoltaic solar cell fabrication.

  3. RTP AREA ROAD GRADE MEASUREMENTS

    EPA Science Inventory

    Grade data collection with GPS equipment is important because the load model component of the MEASURE model uses grade to predict the vehicle load. To date, data collection has been conducted for high priority roads and this task will include other roads not included in the firs...

  4. Coastal Studies for Primary Grades.

    ERIC Educational Resources Information Center

    Butler, Venetia R.; Roach, Ellen M.

    1986-01-01

    Describes a set of field trips for participants of the Coastal Environmental Education for Primary Grades program in Georgia. Includes a sample of the activities used by first- and second-grade students. Discusses follow-up activities and the need for more educational programs dealing with sand dunes and saltwater marshes. (TW)

  5. Teaching Literacy in Fourth Grade

    ERIC Educational Resources Information Center

    Johnson, Denise

    2008-01-01

    Fourth grade is an important year for literacy learning. Having left the primary grades behind, students must grapple with more demanding texts and content material. Effective, motivating instruction can help them succeed. This book helps teachers create an energized and organized learning environment in which all students can improve their…

  6. Elementary Science Curriculum, Grade 3.

    ERIC Educational Resources Information Center

    Stoneham Public Schools, MA.

    This is one of a set of curriculum guides for the Stoneham Elementary School Science Program (see SE 012 153 - SE 012 158). Each guide contains a chart illustrating the scope and sequence of the physical, life, and earth sciences introduced at each grade level. For each of the topics introduced at this grade level, an overview of the topic, a list…

  7. Predictors of General Chemistry Grades.

    ERIC Educational Resources Information Center

    Ozsogomonyan, Ardas; Loftus, Drew

    1979-01-01

    Chemistry pretest scores, high school chemistry grades and, to a greater extent, math SAT scores were useful predictors of college general chemistry grades. Regression analysis of all these predictors combined was used to construct an expectancy table which is being used to identify and advise underprepared students. (BB)

  8. Competitive Grading Sabotages Good Teaching.

    ERIC Educational Resources Information Center

    Krumboltz, John D.; Yeh, Christine J.

    1996-01-01

    Competitive grading stresses judging over learning. Assigning competitive grades adversely affects teachers by turning them into students' opponents, justifying inadequate teaching methods, trivializing course content, encouraging evaluation methods that misdirect and inhibit student learning, and rewarding teachers for punishing students. High…

  9. Clinical Grading in Psychiatric Clerkships

    ERIC Educational Resources Information Center

    Briscoe, Gregory W.; Carlson, David L.; Fore Arcand, Lisa; Levine, Ruth E.; Cohen, Mitchell J.

    2006-01-01

    Objective: The clinical grade assessment is the most frequently used and heavily weighted component in the overall assessment of U.S. psychiatry clerkship students, yet the topic is understudied. The authors aimed to learn more about the nature, perceived virtues, and deficiencies of the clinical grade evaluation. Methods: A 26-item questionnaire…

  10. Student Expectations of Grade Inflation.

    ERIC Educational Resources Information Center

    Landrum, R. Eric

    1999-01-01

    College students completed evaluation-of-teaching surveys in five different courses to develop an evaluation instrument that would provide results concerning faculty performance. Two questions examined students' expectations regarding grades. Results indicated a significant degree of expected grade inflation. Large proportions of students doing…

  11. Elementary Science Curriculum, Grade 5.

    ERIC Educational Resources Information Center

    Stoneham Public Schools, MA.

    This is one of a set of curriculum guides for the Stoneham Elementary School Science Program (see SE 012 153 - SE 012 158). Each guide contains a chart illustrating the scope and sequence of the physical, life, and earth sciences introduced at each grade level. For each of the topics introduced at this grade level an overview of the topic, a list…

  12. Graded Hilbert C*-modules

    SciTech Connect

    Wang, Chunxiang

    2014-02-15

    The notion of Hilbert C*-modules graded by a semilattice was first introduced in the study of many-body systems. We show the relationship between these Hilbert C*-modules and their homogeneous subspaces. We study the stability of graded Hilbert C*-modules under tensor products and crossed products.

  13. Annotated Bibliography, Grades K-6.

    ERIC Educational Resources Information Center

    Massachusetts Dept. of Education, Boston. Bureau of Nutrition Education and School Food Services.

    This annotated bibliography on nutrition is for the use of teachers at the elementary grade level. It contains a list of books suitable for reading about nutrition and foods for pupils from kindergarten through the sixth grade. Films and audiovisual presentations for classroom use are also listed. The names and addresses from which these materials…

  14. Science Grade 7, Long Form.

    ERIC Educational Resources Information Center

    New York City Board of Education, Brooklyn, NY. Bureau of Curriculum Development.

    The Grade 7 Science course of study was prepared in two parallel forms. A short form designed for students who had achieved a high measure of success in previous science courses; the long form for those who have not been able to maintain the pace. Both forms contain similar content. The Grade 7 guide is the first in a three-year sequence for…

  15. Science: Grade 7. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  16. Science: Grade 9. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  17. Science: Grade 6. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  18. Science: Grade 5. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  19. Science: Grade 8. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  20. Science: Grade 2. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This guide is one of a set of 10 science guides, each covering a separate grade in Manitoba, together covering kindergarten through grade 9. The guides have been designed to provide a framework for building scientific concepts and developing the learning of process skills. They replace an earlier set of guides dated 1979. Each guide is essentially…

  1. Practicing Good Habits, Grade 4.

    ERIC Educational Resources Information Center

    Van Cong Lau; And Others

    This illustrated textbook was designed for teaching civics and values to fourth grade students in Vietnam. It is divided into six chapters: (1) At School (recapitulation of the grade three program, friendship, respect for the teacher, team work, discipline, honor); (2) In the Street: Traffic Regulations; (3) At Home (the extended family spirit,…

  2. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Phoenix Refrigeration Systems, Inc.'s heat pipe addition to the Phoenix 2000, a supermarket rooftop refrigeration/air conditioning system, resulted from the company's participation in a field test of heat pipes. Originally developed by NASA to control temperatures in space electronic systems, the heat pipe is a simple, effective, heat transfer system. It has been used successfully in candy storage facilities where it has provided significant energy savings. Additional data is expected to fully quantify the impact of the heat pipes on supermarket air conditioning systems.

  3. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Heat Pipes were originally developed by NASA and the Los Alamos Scientific Laboratory during the 1960s to dissipate excessive heat build- up in critical areas of spacecraft and maintain even temperatures of satellites. Heat pipes are tubular devices where a working fluid alternately evaporates and condenses, transferring heat from one region of the tube to another. KONA Corporation refined and applied the same technology to solve complex heating requirements of hot runner systems in injection molds. KONA Hot Runner Systems are used throughout the plastics industry for products ranging in size from tiny medical devices to large single cavity automobile bumpers and instrument panels.

  4. [Regression grading in gastrointestinal tumors].

    PubMed

    Tischoff, I; Tannapfel, A

    2012-02-01

    Preoperative neoadjuvant chemoradiation therapy is a well-established and essential part of the interdisciplinary treatment of gastrointestinal tumors. Neoadjuvant treatment leads to regressive changes in tumors. To evaluate the histological tumor response different scoring systems describing regressive changes are used and known as tumor regression grading. Tumor regression grading is usually based on the presence of residual vital tumor cells in proportion to the total tumor size. Currently, no nationally or internationally accepted grading systems exist. In general, common guidelines should be used in the pathohistological diagnostics of tumors after neoadjuvant therapy. In particularly, the standard tumor grading will be replaced by tumor regression grading. Furthermore, tumors after neoadjuvant treatment are marked with the prefix "y" in the TNM classification. PMID:22293790

  5. Heating of heavy ions on auroral field lines

    SciTech Connect

    Nishikawa, K.I.; Okuda, H., Hasegawa, A.

    1983-01-01

    Heating of heavy ions is studied in the presence of large amplitude hydrogen cyclotron waves. A three wave decay process, in which a large amplitude pump hydrogen cyclotron wave decays into a daughter hydrogen cyclotron wave and a low frequency oxygen cyclotron wave, is studied theoretically and by numerical simulations. The numerical simulations show a decay instability resulting in strong heating of both the oxygen ions and the hydrogen ions. In particular, the high energy tail of the oxygen ions is observed in the perpendicular distribution.

  6. 7 CFR 810.1404 - Grades and grade requirements for sorghum.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... kernels: Heat (part of total) 0.2 0.5 1.0 3.0 Total 2.0 5.0 10.0 15.0 Broken kernels and foreign material: Foreign material (part of total) 1.0 2.0 3.0 4.0 Total 3.0 6.0 8.0 10.0 Maximum count limits of Other... Unknown foreign substance 3 3 3 3 Cockleburs 7 7 7 7 Total 3 10 10 10 10 U.S. Sample grade is sorghum...

  7. Multiple photon emission in heavy particle decays

    NASA Technical Reports Server (NTRS)

    Asakimori, K.; Burnett, T. H.; Cherry, M. L.; Christl, M. J.; Dake, S.; Derrickson, J. H.; Fountain, W. F.; Fuki, M.; Gregory, J. C.; Hayashi, T.

    1994-01-01

    Cosmic ray interactions, at energies above 1 TeV/nucleon, in emulsion chambers flown on high altitude balloons have yielded two events showing apparent decays of a heavy particle into one charged particle and four photons. The photons converted into electron pairs very close to the decay vertex. Attempts to explain this decay topology with known particle decays are presented. Unless both events represent a b yields u transition, which is statistically unlikely, then other known decay modes for charmed or bottom particles do not account satisfactorily for these observations. This could indicate, possibly, a new decay channel.

  8. Rare B decays at CDF

    SciTech Connect

    Farrington, Sinead M.; /Liverpool U.

    2006-10-01

    The confidence level limits of the CDF search for the B{sub s}{sup 0} and B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -} rare decays and the branching ratio measurement of B{sub s}{sup 0} {yields} D{sub s}{sup +} D{sub s}{sup -} are presented.

  9. Fermi's β-DECAY Theory

    NASA Astrophysics Data System (ADS)

    Yang, Chen Ning

    2013-05-01

    Throughout his lifetime Enrico Fermi (1901-1954) had considered his 1934 β-decay theory as his most important contribution to theoretical physics. E. Segrè (1905-1989) had vividly written about an episode at the inception of that paper:1...

  10. Review of tau lepton decays

    SciTech Connect

    Stoker, D.P.

    1991-07-01

    Measurements of the {tau} decay modes are reviewed and compared with the predictions of the Standard Model. While the agreement is generally good, the status of the 1-prong puzzle'' remains controversial and a discrepancy between the measured leptonic branching fractions and the {tau} lifetime persists. Prospects for precision measurements at a Tau-Charm Factory are also reviewed. 20 refs., 2 tabs.

  11. Nuclear structure from radioactive decay

    SciTech Connect

    Wood, J.L.

    1990-09-30

    This report discusses the nuclear structure of the following isotopes as a result of radioactive decays: neutron-deficient iridium isotopes; neutron-deficient platinum isotopes; neutron-deficient gold isotopes; neutron-deficient mercury isotopes; neutron-deficient thallium isotopes; neutron-deficient lead isotopes; neutron-deficient promethium isotopes; and neutron-deficient samarium isotopes.

  12. Entanglement entropy in particle decay

    NASA Astrophysics Data System (ADS)

    Lello, Louis; Boyanovsky, Daniel; Holman, Richard

    2013-11-01

    The decay of a parent particle into two or more daughter particles results in an entangled quantum state as a consequence of conservation laws in the decay process. Recent experiments at Belle and BaBar take advantage of quantum entanglement and the correlations in the time evolution of the product particles to study CP and T violations. If one (or more) of the product particles are not observed, their degrees of freedom are traced out of the pure state density matrix resulting from the decay, leading to a mixed state density matrix and an entanglement entropy. This entropy is a measure of the loss of information present in the original quantum correlations of the entangled state. We use the Wigner-Weisskopf method to construct an approximation to this state that evolves in time in a manifestly unitary way. We then obtain the entanglement entropy from the reduced density matrix of one of the daughter particles obtained by tracing out the unobserved states, and follow its time evolution. We find that it grows over a time scale determined by the lifetime of the parent particle to a maximum, which when the width of the parent particle is narrow, describes the phase space distribution of maximally entangled Bell-like states. The method is generalized to the case in which the parent particle is described by a wave packet localized in space. Possible experimental avenues to measure the entanglement entropy in the decay of mesons at rest are discussed.

  13. Electrical Experiments. VT-214-10-1. Part One. Grade 10. Experiments 1-63 Revised.

    ERIC Educational Resources Information Center

    Connecticut State Dept. of Education, Hartford. Div. of Vocational Education.

    Designed for tenth-grade students, this activity book contains sixty-three electrical experiments. Experiments focus on topics such as the direction of flow of electricity in an electric circuit, comparison of heating effect using different amounts of current, comparison of heating effects of electric current in conductors of different sizes, and…

  14. Acoustic emission during tensile deformation of M250 grade maraging steel

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, Chandan Kumar; Rajkumar, Kesavan Vadivelu; Chandra Rao, Bhaghi Purna; Jayakumar, Tamanna

    2012-05-01

    Acoustic emission (AE) generated during room temperature tensile deformation of varyingly heat treated (solution annealed and thermally aged) M250 grade maraging steel specimens have been studied. Deformation of microstructure corresponding to different heat treated conditions in this steel could be distinctly characterized using the AE parameters such as RMS voltage, counts and peak amplitude of AE hits (events).

  15. 7 CFR 52.772 - Grades.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... United States Standards for Grades of Canned Red Tart Pitted Cherries 1 Identity and Grades § 52.772 Grades. (a) “U.S. Grade A” (or “U.S. Fancy”) is the quality of canned red tart pitted cherries that have.... Canned red tart pitted cherries of this grade may contain not more than eight cherries per sample...

  16. 7 CFR 51.304 - Combination grades.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Grades § 51.304 Combination grades...) Combinations other than these are not permitted in connection with the U.S. apple grades. When Combination grades are packed, at least 50 percent of the apples in any lot shall meet the requirements of the...

  17. 7 CFR 51.304 - Combination grades.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Grades § 51.304 Combination grades...) Combinations other than these are not permitted in connection with the U.S. apple grades. When Combination grades are packed, at least 50 percent of the apples in any lot shall meet the requirements of the...

  18. [GRADE: Methodology for formulating and grading recommendations in clinical practice].

    PubMed

    Sanabria, Andrea Juliana; Rigau, David; Rotaeche, Rafael; Selva, Anna; Marzo-Castillejo, Mercè; Alonso-Coello, Pablo

    2015-01-01

    Clinical practice guidelines (CPG) provide recommendations on the benefits and harms of different healthcare interventions. Proper CPG development and implementation can potentially reduce variability in clinical practice while improving its quality and safety. The GRADE system is used to assess the quality of evidence and to grade the strength of recommendations in the context of the development of CPGs, systematic reviews or health technology assessments. The aim of this article is to describe the main characteristics of the GRADE system through relevant examples in the context of primary care. PMID:24684818

  19. Ion acoustic wave collapse via two-ion wave decay: 2D Vlasov simulation and theory

    NASA Astrophysics Data System (ADS)

    Chapman, Thomas; Berger, Richard; Banks, Jeffrey; Brunner, Stephan

    2015-11-01

    The decay of ion acoustic waves (IAWs) via two-ion wave decay may transfer energy from the electric field of the IAWs to the particles, resulting in a significant heating of resonant particles. This process has previously been shown in numerical simulations to decrease the plasma reflectivity due to stimulated Brillouin scattering. Two-ion wave decay is a fundamental property of ion acoustic waves that occurs over most if not all of the parameter space of relevance to inertial confinement fusion experiments, and can lead to a sudden collapse of IAWs. The treatment of all species kinetically, and in particular the electrons, is required to describe the decay process correctly. We present fully kinetic 2D+2V Vlasov simulations of IAWs undergoing decay to a highly nonlinear turbulent state using the code LOKI. The scaling of the decay rate with characteristic plasma parameters and wave amplitude is shown. A new theory describing two-ion wave decay in 2D, that incorporates key kinetic properties of the electrons, is presented and used to explain quantitatively for the first time the observed decay of IAWs. Work performed under auspices of U.S. DoE by LLNL, Contract DE-AC52-07NA2734. Funded by LDRD 15-ERD-038 and supported by LLNL Grand Challenge allocation.

  20. Staffroom Interchange: Avoiding Whadjaget with No-Grade, Graded Papers.

    ERIC Educational Resources Information Center

    Birdsall, Eric R.

    1979-01-01

    Describes a technique for increasing students' concern for the merits of their papers and for their teachers' suggestions by withholding the grade each paper receives and offering the opportunity to rewrite. (DD)

  1. Heated Goggles

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The electrically heated ski goggles shown incorporate technology similar to that once used in Apollo astronauts' helmet visors, and for the same reason-providing fogfree sight in an activity that demands total vision. Defogging is accomplished by applying heat to prevent moisture condensation. Electric heat is supplied by a small battery built into the h goggles' headband. Heat is spread across the lenses by means of an invisible coating of electrically conductive metallic film. The goggles were introduced to the market last fall. They were designed by Sierracin Corporation, Sylmar, California, specialists in the field of heated transparent materials. The company produces heated windshields for military planes and for such civil aircraft as the Boeing 747, McDonnell Douglas DC-10 and Lockheed L-1011 TriStar.

  2. Neutron Beta Decay Studies with Nab

    SciTech Connect

    Baessler, S.; Alarcon, R.; Alonzi, L. P.; Balascuta, S.; Barron-Palos, L.; Bowman, James David; Bychkov, M. A.; Byrne, J.; Calarco, J; Chupp, T.; Cianciolo, T. V.; Crawford, C.; Frlez, E.; Gericke, M. T.; Glück, F.; Greene, G. L.; Grzywacz, R. K.; Gudkov, V.; Harrison, D.; Hersman, F. W.; Ito, T.; Makela, M.; Martin, J.; McGaughey, P. L.; McGovern, S.; Page, S.; Penttila, Seppo I; Pocanic, Dinko; Salas-Bacci, A.; Tompkins, Z.; Wagner, D.; Wilburn, W. S.; Young, A. R.

    2013-01-01

    Precision measurements in neutron beta decay serve to determine the coupling constants of beta decay and allow for several stringent tests of the standard model. This paper discusses the design and the expected performance of the Nab spectrometer.

  3. Decay Spectroscopy for Nuclear Astrophysics: {beta}-delayed Proton Decay

    SciTech Connect

    Trache, L.; Simmons, E.; Spiridon, A.; McCleskey, M.; Roeder, B. T.; Tribble, R. E.; Saastamoinen, A.; Jokinen, A.; Aysto, J.; Davinson, T.; Woods, P. J.; Pollacco, E.; Kebbiri, M.

    2011-11-30

    Decay spectroscopy is one of the oldest indirect methods in nuclear astrophysics. We have developed at TAMU techniques to measure beta- and beta-delayed proton decay of sd-shell, proton-rich nuclei. The short-lived radioactive species are produced in-flight, separated, then slowed down (from about 40 MeV/u) and implanted in the middle of very thin Si detectors. These allowed us to measure protons with energies as low as 200 keV from nuclei with lifetimes of 100 ms or less. At the same time we measure gamma-rays up to 8 MeV with high resolution HPGe detectors. We have studied the decay of {sup 23}Al, {sup 27}P, {sup 31}Cl, all important for understanding explosive H-burning in novae. The technique has shown a remarkable selectivity to beta-delayed charged-particle emission and works even at radioactive beam rates of a few pps. The states populated are resonances for the radiative proton capture reactions {sup 22}Na(p,{gamma}){sup 23}Mg(crucial for the depletion of {sup 22}Na in novae), {sup 26m}Al(p,{gamma}){sup 27}Si and {sup 30}P(p,{gamma}){sup 31}S(bottleneck in novae and XRB burning), respectively. More recently we have radically improved the technique using a gas based detector we call AstroBox.

  4. Decays of near BPS heterotic strings

    SciTech Connect

    Gutperle, Michael; Krym, Darya

    2006-10-15

    The decay of highly excited massive string states in compactified heterotic string theories is discussed. We calculate the decay rate and spectrum of states carrying momentum and winding in the compactified direction. The longest lived states in the spectrum are near Bogomol'nyi-Prasad-Sommerfield (BPS) states whose decay is dominated by a single decay channel of massless radiation which brings the state closer to being BPS.

  5. 7 CFR 810.2204 - Grades and grade requirements for wheat.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 7 2013-01-01 2013-01-01 false Grades and grade requirements for wheat. 810.2204... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Wheat Principles Governing the Application of Standards § 810.2204 Grades and grade requirements for wheat. (a) Grades and grade...

  6. 7 CFR 810.2204 - Grades and grade requirements for wheat.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Grades and grade requirements for wheat. 810.2204... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Wheat Principles Governing the Application of Standards § 810.2204 Grades and grade requirements for wheat. (a) Grades and grade...

  7. 7 CFR 810.2204 - Grades and grade requirements for wheat.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 false Grades and grade requirements for wheat. 810.2204... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Wheat Principles Governing the Application of Standards § 810.2204 Grades and grade requirements for wheat. (a) Grades and grade...

  8. 7 CFR 810.1604 - Grades and grade requirements for soybeans.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 7 2013-01-01 2013-01-01 false Grades and grade requirements for soybeans. 810.1604... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Soybeans Principles Governing the Application of Standards § 810.1604 Grades and grade requirements for soybeans. Grading factors Grades...

  9. 7 CFR 810.1604 - Grades and grade requirements for soybeans.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 false Grades and grade requirements for soybeans. 810.1604... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Soybeans Principles Governing the Application of Standards § 810.1604 Grades and grade requirements for soybeans. Grading factors Grades...

  10. 7 CFR 810.1604 - Grades and grade requirements for soybeans.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Grades and grade requirements for soybeans. 810.1604... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Soybeans Principles Governing the Application of Standards § 810.1604 Grades and grade requirements for soybeans. Grading factors Grades...

  11. 7 CFR 810.1604 - Grades and grade requirements for soybeans.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Grades and grade requirements for soybeans. 810.1604... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Soybeans Principles Governing the Application of Standards § 810.1604 Grades and grade requirements for soybeans. Grading factors Grades...

  12. 7 CFR 810.1604 - Grades and grade requirements for soybeans.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Grades and grade requirements for soybeans. 810.1604... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Soybeans Principles Governing the Application of Standards § 810.1604 Grades and grade requirements for soybeans. Grading factors Grades...

  13. Solitons versus parametric instabilities during ionospheric heating

    NASA Technical Reports Server (NTRS)

    Nicholson, D. R.; Payne, G. L.; Downie, R. M.; Sheerin, J. P.

    1984-01-01

    Various effects associated with ionospheric heating are investigated by numerically solving the modified Zakharov (1972) equations. It is shown that, for typical ionospheric parameters, the modulational instability is more important than the parametric decay instability in the spatial region of strongest heater electric field. It is concluded that the modulational instability leads to the formation of solitons, as originally predicted by Petviashvili (1976).

  14. Depolarization of decaying counterflow turbulence in He II.

    PubMed

    Barenghi, C F; Gordeev, A V; Skrbek, L

    2006-08-01

    We present experimental evidence backed up by numerical simulations that the steady-state vortex tangle created in He II by heat-transfer counterflow is strongly polarized. When the heater that generates the counterflow turbulence is switched off, the vortex tangle decays, the vortex lines randomize their spatial orientation and the tangle's polarization decreases. The process of depolarization slows down the recovery of the transverse second sound signal which measures the vortex line density; at some values of parameters it even leads to a net decrease of the amplitude of the transverse second sound prior to reaching the universal -32 power temporal law decay typical of classical homogeneous isotropic turbulence in a finite-sized channel. PMID:17025541

  15. Depolarization of decaying counterflow turbulence in He II

    SciTech Connect

    Barenghi, C. F.; Gordeev, A. V.; Skrbek, L.

    2006-08-15

    We present experimental evidence backed up by numerical simulations that the steady-state vortex tangle created in He II by heat-transfer counterflow is strongly polarized. When the heater that generates the counterflow turbulence is switched off, the vortex tangle decays, the vortex lines randomize their spatial orientation and the tangle's polarization decreases. The process of depolarization slows down the recovery of the transverse second sound signal which measures the vortex line density; at some values of parameters it even leads to a net decrease of the amplitude of the transverse second sound prior to reaching the universal -3/2 power temporal law decay typical of classical homogeneous isotropic turbulence in a finite-sized channel.

  16. Penguin and rare decays in BABAR

    NASA Astrophysics Data System (ADS)

    Akar, Simon; Babar Collaboration

    2014-11-01

    We present recent results from the BABAR Collaboration on radiative decays. These include searches for new physics via measurements of several observables such as the time- dependent CP asymmetry in B0 → K0Sπ-π+γ exclusive decays, as well as direct CP asymmetries and branching fractions in B → Xsγ and B → Xsl+l- inclusive decays.

  17. Weak radiative baryonic decays of B mesons

    SciTech Connect

    Kohara, Yoji

    2004-11-01

    Weak radiative baryonic B decays B{yields}B{sub 1}B{sub 2}-bar{gamma} are studied under the assumption of the short-distance b{yields}s{gamma} electromagnetic penguin transition dominance. The relations among the decay rates of various decay modes are derived.

  18. Review of B and Bs decays

    NASA Astrophysics Data System (ADS)

    Bozzi, Concezio

    2014-05-01

    A review of B and Bs decays is presented. Emphasis is given to processes most sensitive to physics beyond the Standard Model, such as radiative, electroweak and "Higgs" penguin decays, and tree-level decays involving tau leptons in the final state. An outlook on future perspectives is also given.

  19. Beauty baryon decays: a theoretical overview

    NASA Astrophysics Data System (ADS)

    Wang, Yu-Ming

    2014-11-01

    I overview the theoretical status and recent progress on the calculations of beauty baryon decays focusing on the QCD aspects of the exclusive semi-leptonic Λb → plμ decay at large recoil and theoretical challenges of radiative and electro-weak penguin decays Λb → Λγ,Λl+l-.

  20. Severity grading in radial dysplasia.

    PubMed

    Vilkki, S K

    2014-11-01

    A functional scoring method to grade the usefulness and quality of the upper limbs in congenital radial dysplasia is presented. It is based on the author's examinations of 44 arms with congenital deficiency of the radius. The hand (H), wrist (W) and proximal parts (P) of the extremity are each scored from 0 to 10 points for severity. The scoring is expressed similarly to the TNM (tumour, nodes, metastasis) tumour classification, for example as H5W4P2. The maximum severity index is 30 points. A severity grade of mild is between 1 and 8 points, moderate between 9 and 16 points and severe 17 points and over. In the author's series, the grades were mild in eight, moderate in 21 and severe in 15 cases. The functional severity grading should allow better comparison of radially deficient limbs and the results of treatment between groups of patients. PMID:24401744