Powered by Deep Web Technologies
Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Vanadium hydride deuterium-tritium generator  

DOE Patents (OSTI)

A pressure controlled vanadium hydride gas generator to provide deuterium-tritium gas in a series of pressure increments. A high pressure chamber filled with vanadium-deuterium-tritium hydride is surrounded by a heater which controls the hydride temperature. The heater is actuated by a power controller which responds to the difference signal between the actual pressure signal and a programmed pressure signal.

Christensen, Leslie D. (Livermore, CA)

1982-01-01T23:59:59.000Z

2

Vanadium hydride deuterium-tritium generator  

DOE Patents (OSTI)

A pressure controlled vanadium hydride gas generator was designed to provide deuterium-tritium gas in a series of pressure increments. A high pressure chamber filled with vanadium-deuterium-tritium hydride is surrounded by a heater which controls the hydride temperature. The heater is actuated by a power controller which responds to the difference signal between the actual pressure signal and a programmed pressure signal.

Christensen, L.D.

1980-03-13T23:59:59.000Z

3

Metal Hydride Thermal Storage: Reversible Metal Hydride Thermal Storage for High-Temperature Power Generation Systems  

SciTech Connect

HEATS Project: PNNL is developing a thermal energy storage system based on a Reversible Metal Hydride Thermochemical (RMHT) system, which uses metal hydride as a heat storage material. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at nightwhen the sun is not outto drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. PNNLs metal hydride material can reversibly store heat as hydrogen cycles in and out of the material. In a RHMT system, metal hydrides remain stable in high temperatures (600- 800C). A high-temperature tank in PNNLs storage system releases heat as hydrogen is absorbed, and a low-temperature tank stores the heat until it is needed. The low-cost material and simplicity of PNNLs thermal energy storage system is expected to keep costs down. The system has the potential to significantly increase energy density.

None

2011-12-05T23:59:59.000Z

4

Method of generating hydrogen-storing hydride complexes  

DOE Patents (OSTI)

A ternary hydrogen storage system having a constant stoichiometric molar ratio of LiNH.sub.2:MgH.sub.2:LiBH.sub.4 of 2:1:1. It was found that the incorporation of MgH.sub.2 particles of approximately 10 nm to 20 nm exhibit a lower initial hydrogen release temperature of 150.degree. C. Furthermore, it is observed that the particle size of LiBNH quaternary hydride has a significant effect on the hydrogen sorption concentration with an optimum size of 28 nm. The as-synthesized hydrides exhibit two main hydrogen release temperatures, one around 160.degree. C. and the other around 300.degree. C., with the main hydrogen release temperature reduced from 310.degree. C. to 270.degree. C., while hydrogen is first reversibly released at temperatures as low as 150.degree. C. with a total hydrogen capacity of 6 wt. % to 8 wt. %. Detailed thermal, capacity, structural and microstructural properties have been demonstrated and correlated with the activation energies of these materials.

Srinivasan, Sesha S; Niemann, Michael U; Goswami, D. Yogi; Stefanakos, Elias K

2013-05-14T23:59:59.000Z

5

Gas atomization processing of tin and silicon modified LaNi{sub 5} for nickel-metal hydride battery applications  

DOE Green Energy (OSTI)

Numerous researchers have studied the relevant material properties of so-called AB{sub 5} alloys for battery applications. These studies involved LaNi{sub 5} substituted alloys which were prepared using conventional cast and crush alloying techniques. While valuable to the understanding of metal hydride effects, the previous work nearly ignored the potential for alternative direct powder production methods, like high pressure gas atomization (HPGA). Thus, there is a need to understand the relationship between gas atomization processes, powder particle solidification phases, and hydrogen absorption properties of ultra fine (< 25 {micro}m) atomized powders with high surface area for enhanced battery performance. Concurrently, development of a gas atomization nozzle that is more efficient than all current designs is needed to increase the yield of ultrafine AB{sub 5} alloy powder for further processing advantage. Gas atomization processing of the AB{sub 5} alloys was demonstrated to be effective in producing ultrafine spherical powders that were resilient to hydrogen cycling for the benefit of improving corrosion resistance in battery application. These ultrafine powders benefited from the rapid solidification process by having refined solute segregation in the microstructure of the gas atomized powders which enabled a rapid anneal treatment of the powders. The author has demonstrated the ability to produce high yields of ultrafine powder efficiently and cost effectively, using the new HPGA-III technology. Thus, the potential benefits of processing AB{sub 5} alloys using the new HPGA technology could reduce manufacturing cost of nickel-metal hydride powder. In the near future, the manufacture of AB{sub 5} alloy powders could become a continuous and rapid production process. The economic benefit of an improved AB{sub 5} production process may thereby encourage the use of nickel-metal hydride rechargeable batteries in electrical vehicle applications in the foreseeable future.

Ting, J.

1999-02-12T23:59:59.000Z

6

Rapid hydrogen gas generation using reactive thermal decomposition of uranium hydride.  

DOE Green Energy (OSTI)

Oxygen gas injection has been studied as one method for rapidly generating hydrogen gas from a uranium hydride storage system. Small scale reactors, 2.9 g UH{sub 3}, were used to study the process experimentally. Complimentary numerical simulations were used to better characterize and understand the strongly coupled chemical and thermal transport processes controlling hydrogen gas liberation. The results indicate that UH{sub 3} and O{sub 2} are sufficiently reactive to enable a well designed system to release gram quantities of hydrogen in {approx} 2 seconds over a broad temperature range. The major system-design challenge appears to be heat management. In addition to the oxidation tests, H/D isotope exchange experiments were performed. The rate limiting step in the overall gas-to-particle exchange process was found to be hydrogen diffusion in the {approx}0.5 {mu}m hydride particles. The experiments generated a set of high quality experimental data; from which effective intra-particle diffusion coefficients can be inferred.

Kanouff, Michael P.; Van Blarigan, Peter; Robinson, David B.; Shugard, Andrew D.; Gharagozloo, Patricia E.; Buffleben, George M.; James, Scott Carlton; Mills, Bernice E.

2011-09-01T23:59:59.000Z

7

Advanced Metal-Hydrides-Based Thermal Battery: A New Generation of High Density Thermal Battery Based on Advanced Metal Hydrides  

Science Conference Proceedings (OSTI)

HEATS Project: The University of Utah is developing a compact hot-and-cold thermal battery using advanced metal hydrides that could offer efficient climate control system for EVs. The teams innovative designs of heating and cooling systems for EVs with high energy density, low-cost thermal batteries could significantly reduce the weight and eliminate the space constraint in automobiles. The thermal battery can be charged by plugging it into an electrical outlet while charging the electric battery and it produces heat and cold through a heat exchanger when discharging. The ultimate goal of the project is a climate-controlling thermal battery that can last up to 5,000 charge and discharge cycles while substantially increasing the driving range of EVs, thus reducing the drain on electric batteries.

None

2011-12-01T23:59:59.000Z

8

Cavity Loss Induced Generation of Entangled Atoms  

E-Print Network (OSTI)

We discuss the generation of entangled states of two two-level atoms inside an optical resonator. When the cavity decay is continuously monitored, the absence of photon-counts is associated with the presence of an atomic entangled state. In addition to being conceptually simple, this scheme could be demonstrated with presently available technology. We describe how such a state is generated through conditional dynamics, using quantum jump methods, including both cavity damping and spontaneous emission decay, and evaluate the fidelity and relative entropy of entanglement of the generated state compared with the target entangled state.

M. B. Plenio; S. F. Huelga; A. Beige; P. L. Knight

1998-11-02T23:59:59.000Z

9

Cavity Loss Induced Generation of Entangled Atoms  

E-Print Network (OSTI)

We discuss the generation of entangled states of two two-level atoms inside an optical resonator. When the cavity decay is continuously monitored, the absence of photon-counts is associated with the presence of an atomic entangled state. In addition to being conceptually simple, this scheme could be demonstrated with presently available technology. We describe how such a state is generated through conditional dynamics, using quantum jump methods, including both cavity damping and spontaneous emission decay, and evaluate the fidelity and relative entropy of entanglement of the generated state compared with the target entangled state.

Plenio, M B; Beige, A; Knight, P L

1999-01-01T23:59:59.000Z

10

Atom-photon entanglement generation and distribution  

E-Print Network (OSTI)

We extend an earlier model by Law {\\it et al.} \\cite{law} for a cavity QED based single-photon-gun to atom-photon entanglement generation and distribution. We illuminate the importance of a small critical atom number on the fidelity of the proposed operation in the strong coupling limit. Our result points to a promisingly high purity and efficiency using currently available cavity QED parameters, and sheds new light on constructing quantum computing and communication devices with trapped atoms and high Q optical cavities.

B. Sun; M. S. Chapman; L. You

2003-08-31T23:59:59.000Z

11

Kinetics and Mechanism of Hydrogen-Atom Abstraction from Rhodium Hydrides by Alkyl Radicals in Aqueous Solutions  

DOE Green Energy (OSTI)

The kinetics of the reaction of benzyl radicals with [L{sup 1}(H{sub 2}O)RhH{l_brace}D{r_brace}]{sup 2+} (L{sup 1}=1,4,8,11-tetraazacyclotetradecane) were studied directly by laser-flash photolysis. The rate constants for the two isotopologues, k=(9.3 {+-} 0.6) x 10{sup 7} M{sup -1} s{sup -1} (H) and (6.2 {+-} 0.3) x 10{sup 7} M{sup -1} s{sup -1} (D), lead to a kinetic isotope effect k{sub H}/k{sub D}=1.5 {+-} 0.1. The same value was obtained from the relative yields of PhCH{sub 3} and PhCH{sub 2}D in a reaction of benzyl radicals with a mixture of rhodium hydride and deuteride. Similarly, the reaction of methyl radicals with {l_brace}[L{sup 1}(H{sub 2}O)RhH]{sup 2+} + [L{sup 1}(H{sub 2}O)RhD]{sup 2+}{r_brace} produced a mixture of CH{sub 4} and CH{sub 3}D that yielded k{sub H}/k{sub D}=1.42 {+-} 0.07. The observed small normal isotope effects in both reactions are consistent with reduced sensitivity to isotopic substitution in very fast hydrogen-atom abstraction reactions. These data disprove a literature report claiming much slower kinetics and an inverse kinetic isotope effect for the reaction of methyl radicals with hydrides of L{sup 1}Rh.

Pestovsky, Oleg; Veysey, Stephen W.; Bakac, Andrej

2011-03-22T23:59:59.000Z

12

Boron hydride polymer coated substrates  

DOE Patents (OSTI)

A method is disclosed for coating a substrate with a uniformly smooth layer of a boron hydride polymer. The method comprises providing a reaction chamber which contains the substrate and the boron hydride plasma. A boron hydride feed stock is introduced into the chamber simultaneously with the generation of a plasma discharge within the chamber. A boron hydride plasma of ions, electrons and free radicals which is generated by the plasma discharge interacts to form a uniformly smooth boron hydride polymer which is deposited on the substrate.

Pearson, R.K.; Bystroff, R.I.; Miller, D.E.

1986-08-27T23:59:59.000Z

13

Boron hydride polymer coated substrates  

DOE Patents (OSTI)

A method is disclosed for coating a substrate with a uniformly smooth layer of a boron hydride polymer. The method comprises providing a reaction chamber which contains the substrate and the boron hydride plasma. A boron hydride feed stock is introduced into the chamber simultaneously with the generation of a plasma discharge within the chamber. A boron hydride plasma of ions, electrons and free radicals which is generated by the plasma discharge interacts to form a uniformly smooth boron hydride polymer which is deposited on the substrate.

Pearson, Richard K. (Pleasanton, CA); Bystroff, Roman I. (Livermore, CA); Miller, Dale E. (Livermore, CA)

1987-01-01T23:59:59.000Z

14

Method of producing a chemical hydride  

DOE Patents (OSTI)

A method of producing a chemical hydride is described and which includes selecting a composition having chemical bonds and which is capable of forming a chemical hydride; providing a source of a hydrocarbon; and reacting the composition with the source of the hydrocarbon to generate a chemical hydride.

Klingler, Kerry M. (Idaho Falls, ID); Zollinger, William T. (Idaho Falls, ID); Wilding, Bruce M. (Idaho Falls, ID); Bingham, Dennis N. (Idaho Falls, ID); Wendt, Kraig M. (Idaho Falls, ID)

2007-11-13T23:59:59.000Z

15

Activated aluminum hydride hydrogen storage compositions and uses thereof  

DOE Patents (OSTI)

In one aspect, the invention relates to activated aluminum hydride hydrogen storage compositions containing aluminum hydride in the presence of, or absence of, hydrogen desorption stimulants. The invention particularly relates to such compositions having one or more hydrogen desorption stimulants selected from metal hydrides and metal aluminum hydrides. In another aspect, the invention relates to methods for generating hydrogen from such hydrogen storage compositions.

Sandrock, Gary (Ringwood, NJ); Reilly, James (Bellport, NY); Graetz, Jason (Mastic, NY); Wegrzyn, James E. (Brookhaven, NY)

2010-11-23T23:59:59.000Z

16

Hydride compositions  

DOE Patents (OSTI)

A composition for use in storing hydrogen, and a method for making the composition. The composition comprises a mixture of two or more hydrides, each hydride having a different series of hydrogen sorption isotherms that contribute to the overall isotherms of the mixture. The hydrides are chosen so that the isotherms of the mixture have regions wherein the hydrogen equilibrium pressure increases with increasing hydrogen, preferably linearly. The isotherms of the mixture can be adjusted by selecting hydrides with different isotherms and by varying the amounts of the individual hydrides, or both. Preferably, the mixture is made up of hydrides that have isotherms with substantially flat plateaus and in nearly equimolar amounts. The composition is activated by degassing, exposing to hydrogen and then heating at a temperature below the softening temperature of any of the. constituents so that their chemical and structural integrity is preserved. When the composition is used to store hydrogen, its hydrogen content can be found simply by measuring P.sub.H.sbsb.2 and determining H/M from the isothermic function of the composition.

Lee, Myung W. (North Augusta, SC)

1995-01-01T23:59:59.000Z

17

Hydride compositions  

DOE Patents (OSTI)

Disclosed are a composition for use in storing hydrogen and a method for making the composition. The composition comprises a mixture of two or more hydrides, each hydride having a different series of hydrogen sorption isotherms that contribute to the overall isotherms of the mixture. The hydrides are chosen so that the isotherms of the mixture have regions wherein the H equilibrium pressure increases with increasing hydrogen, preferably linearly. The isotherms of the mixture can be adjusted by selecting hydrides with different isotherms and by varying the amounts of the individual hydrides, or both. Preferably, the mixture is made up of hydrides that have isotherms with substantially flat plateaus and in nearly equimolar amounts. The composition is activated by degassing, exposing to H, and then heating below the softening temperature of any of the constituents. When the composition is used to store hydrogen, its hydrogen content can be found simply by measuring P{sub H}{sub 2} and determining H/M from the isothermic function of the composition.

Lee, Myung, W.

1994-01-01T23:59:59.000Z

18

Remote generation of entanglement for individual atoms via optical fibers  

E-Print Network (OSTI)

The generation of atomic entanglement is discussed in a system that atoms are trapped in separate cavities which are connected via optical fibers. Two distant atoms can be projected to Bell-state by synchronized turning off the local laser fields and then performing a single quantum measurement by a distant controller. The distinct advantage of this scheme is that it works in a regime that $\\Delta\\approx\\kappa\\gg g$, which makes the scheme insensitive to cavity strong leakage. Moreover, the fidelity is not affected by atomic spontaneous emission.

Y. Q. Guo; H. Y. Zhong; Y. H. Zhang; H. S. Song

2008-05-29T23:59:59.000Z

19

Hydride compressor  

DOE Patents (OSTI)

Method of producing high energy pressurized gas working fluid power from a low energy, low temperature heat source, wherein the compression energy is gained by using the low energy heat source to desorb hydrogen gas from a metal hydride bed and the desorbed hydrogen for producing power is recycled to the bed, where it is re-adsorbed, with the recycling being powered by the low energy heat source. In one embodiment, the adsorption-desorption cycle provides a chemical compressor that is powered by the low energy heat source, and the compressor is connected to a regenerative gas turbine having a high energy, high temperature heat source with the recycling being powered by the low energy heat source.

Powell, James R. (Wading River, NY); Salzano, Francis J. (Patchogue, NY)

1978-01-01T23:59:59.000Z

20

Advanced Hydride Laboratory  

DOE Green Energy (OSTI)

Metal hydrides have been used at the Savannah River Tritium Facilities since 1984. However, the most extensive application of metal hydride technology at the Savannah River Site is being planned for the Replacement Tritium Facility, a $140 million facility schedules for completion in 1990 and startup in 1991. In the new facility, metal hydride technology will be used to store, separate, isotopically purify, pump, and compress hydrogen isotopes. In support of the Replacement Tritium Facility, a $3.2 million, cold,'' process demonstration facility, the Advanced Hydride Laboratory began operation in November of 1987. The purpose of the Advanced Hydride Laboratory is to demonstrate the Replacement Tritium Facility's metal hydride technology by integrating the various unit operations into an overall process. This paper will describe the Advanced Hydride Laboratory, its role and its impact on the application of metal hydride technology to tritium handling.

Motyka, T.

1989-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Silica Embedded Metal Hydrides  

DOE Green Energy (OSTI)

A method to produce silica embedded metal hydride was developed. The product is a composite in which metal hydride particles are embedded in a matrix of silica. The silica matrix is highly porous. Hydrogen gas can easily reach the embedded metal hydride particles. The pores are small so that the metal hydride particles cannot leave the matrix. The porous matrix also protects the metal hydride particles from larger and reactive molecules such as oxygen, since the larger gas molecules cannot pass through the small pores easily. Tests show that granules of this composite can absorb hydrogen readily and withstand many cycles without making fines.

Heung, L.K. [Westinghouse Savannah River Company, AIKEN, SC (United States); Wicks, G.G.

1998-08-01T23:59:59.000Z

22

Velocity distribution measurements in atomic beams generated using laser induced back-ablation  

E-Print Network (OSTI)

We present measurements of the velocity distribution of calcium atoms in an atomic beam generated using a dual-stage laser back-ablation apparatus. Distributions are measured using a velocity selective Doppler time-of-flight technique. They are Boltzmann-like with rms velocities corresponding to temperatures above the melting point for calcium. Contrary to a recent report in the literature, this method does not generate a sub-thermal atomic beam.

Denning, A; Lee, S; Ammonson, M; Bergeson, S D

2008-01-01T23:59:59.000Z

23

Transition-Metal Hydrides  

NLE Websites -- All DOE Office Websites (Extended Search)

Transition-Metal Hydride Electrochromics Transition-Metal Hydride Electrochromics A new type of electrochromic hydride material has interesting and unusual properties. Thin Ni-Mg films, for example, are mirror-like in appearance and have very low visible transmittance. On exposure to hydrogen gas or on reduction in alkaline electrolyte, the films become transparent. The transition is believed to result from formation of nickel magnesium hydride, Mg2NiH4. Switchable mirrors based on rare earth hydrides were discovered in 1996 at Vrije University in the Netherlands, Rare earth-magnesium alloy films were subsequently found to be superior to the pure lanthanides in maximum transparency and mirror-state reflectivity by Philips Laboratories. The newer transition-metal types which use less expensive and less reactive materials were discovered at LBNL. This has now become a very active area of study with a network of researchers.

24

Correlated photon pairs generated from a warm atomic ensemble  

E-Print Network (OSTI)

We present measurements of the cross-correlation function of photon pairs at 780 nm and 1367 nm, generated in a hot rubidium vapor cell. The temporal character of the biphoton is determined by the dispersive properties of the medium where the pair generation takes place. We show that short correlation times occur for optically thick samples, which can be understood in terms of off-resonant pair generation. By modifying the linear response of the sample, we produce near-resonant photon pairs, which could in principle be used for entanglement distribution.

Willis, R T; Orozco, L A; Rolston, S L

2010-01-01T23:59:59.000Z

25

Correlated photon pairs generated from a warm atomic ensemble  

E-Print Network (OSTI)

We present measurements of the cross-correlation function of photon pairs at 780 nm and 1367 nm, generated in a hot rubidium vapor cell. The temporal character of the biphoton is determined by the dispersive properties of the medium where the pair generation takes place. We show that short correlation times occur for optically thick samples, which can be understood in terms of off-resonant pair generation. By modifying the linear response of the sample, we produce near-resonant photon pairs, which could in principle be used for entanglement distribution.

R. T. Willis; F. E. Becerra; L. A. Orozco; S. L. Rolston

2010-11-11T23:59:59.000Z

26

Quasideterministic generation of maximally entangled states of two mesoscopic atomic ensembles by adiabatic quantum feedback  

Science Conference Proceedings (OSTI)

We introduce an efficient, quasideterministic scheme to generate maximally entangled states of two atomic ensembles. The scheme is based on quantum nondemolition measurements of total atomic populations and on adiabatic quantum feedback conditioned by the measurements outputs. The high efficiency of the scheme is tested and confirmed numerically for ideal photodetection as well as in the presence of losses.

Di Lisi, Antonio; De Siena, Silvio; Illuminati, Fabrizio [Dipartimento di Fisica 'E. R. Caianiello', Universita di Salerno, INFM-Coherentia, and INFN Sezione di Napoli, Gruppo collegato di Salerno, Via S. Allende, I-84081 Baronissi, SA (Italy); Vitali, David [Dipartimento di Fisica, Universita di Camerino, I-62032 Camerino, MC (Italy)

2005-09-15T23:59:59.000Z

27

Quasideterministic generation of maximally entangled states of two mesoscopic atomic ensembles by adiabatic quantum feedback  

E-Print Network (OSTI)

We introduce an efficient, quasideterministic scheme to generate maximally entangled states of two atomic ensembles. The scheme is based on quantum nondemolition measurements of total atomic populations and on adiabatic quantum feedback conditioned by the measurements outputs. The high efficiency of the scheme is tested and confirmed numerically for ideal photodetection as well as in the presence of losses.

Antonio Di Lisi; Silvio De Siena; Fabrizio Illuminati; David Vitali

2004-07-29T23:59:59.000Z

28

Entanglement generation between two atoms via surface modes  

SciTech Connect

We discuss the coupling of two identical atoms, separated by a metal or metamaterial slab, through surface modes. We show that the coupling through the surface modes can induce entanglement. We discuss how to control the coupling for the metal or metamaterial slab by adjusting the symmetrical and antisymmetrical property of the surface modes. We analyze the dispersion relation of the surface modes and study the parameter ranges that support the surface modes with the same properties. Our results have potential applications in quantum communication and quantum computation.

Xu Jingping; Yang Yaping [Key Laboratory of Advanced Micro-structure Materials, Ministry of Education, Department of Physics, Tongji University, Shanghai 200092 (China); Al-Amri, M. [National Center for Mathematics and Physics, KACST, P.O. Box 6086, Riyadh 11442 (Saudi Arabia); Zhu Shiyao [Key Laboratory of Advanced Micro-structure Materials, Ministry of Education, Department of Physics, Tongji University, Shanghai 200092 (China); Beijing Computational Science Research Center, Beijing 100084 (China); Department of Physics, Hong Kong Baptist University (Hong Kong); Zubairy, M. Suhail [Beijing Computational Science Research Center, Beijing 100084 (China); Institute for Quantum Science and Engineering (IQSE) and Department of Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States)

2011-09-15T23:59:59.000Z

29

Chemistry of intermetallic hydrides  

DOE Green Energy (OSTI)

Certain intermetallic hydrides are safe, convenient and inexpensive hydrogen storage compounds. A particular advantage of such compounds is the ease with which their properties can be modified by small changes in alloy composition or preparation. This quality can be exploited to optimize their storage properties for particular applications, e.g. as intermetallic hydride electrodes in batteries. We will be concerned herein with the more important aspects of the thermodynamic and structural principles which regulate the behavior of intermetallic hydrogen systems and then illustrate their application using the archetype hydrides of LaNi5, FeTi and Mg alloys. The practical utility of these classes of materials will be briefly noted.

Reilly, J.J.

1991-01-01T23:59:59.000Z

30

Hydride heat pump  

DOE Patents (OSTI)

Method and apparatus for the use of hydrides to exhaust heat from one temperature source and deliver the thermal energy extracted for use at a higher temperature, thereby acting as a heat pump. For this purpose there are employed a pair of hydridable metal compounds having different characteristics working together in a closed pressure system employing a high temperature source to upgrade the heat supplied from a low temperature source.

Cottingham, James G. (Center Moriches, NY)

1977-01-01T23:59:59.000Z

31

Controlled generation of field squeezing with cold atomic clouds coupled to a superconducting transmission line resonator  

E-Print Network (OSTI)

We propose an efficient method for controlled generation of field squeezing with cold atomic clouds trapped close to a superconducting transmission line resonator. It is shown that, based on the coherent strong magnetic coupling between the collective atomic spins and microwave fields in the transmission line resonator, two-mode or single mode field squeezed states can be generated through coherent control on the dynamics of the system. The degree of squeezing and preparing time can be directly controlled through tuning the external classical fields. This protocol may offer a promising platform for implementing scalable on-chip quantum information processing with continuous variables.

Li, Peng-Bo

2010-01-01T23:59:59.000Z

32

Controlled generation of field squeezing with cold atomic clouds coupled to a superconducting transmission line resonator  

E-Print Network (OSTI)

We propose an efficient method for controlled generation of field squeezing with cold atomic clouds trapped close to a superconducting transmission line resonator. It is shown that, based on the coherent strong magnetic coupling between the collective atomic spins and microwave fields in the transmission line resonator, two-mode or single mode field squeezed states can be generated through coherent control on the dynamics of the system. The degree of squeezing and preparing time can be directly controlled through tuning the external classical fields. This protocol may offer a promising platform for implementing scalable on-chip quantum information processing with continuous variables.

Peng-Bo Li; Fu-Li Li

2010-02-26T23:59:59.000Z

33

atomic  

NLE Websites -- All DOE Office Websites (Extended Search)

theory and fundamental quantum mechanics In addition to research on hadronic and nuclear physics, we also conduct research in atomic physics, neutron physics, and quantum...

34

Method for preparing porous metal hydride compacts  

DOE Patents (OSTI)

A method for preparing porous metallic-matrix hydride compacts which can be repeatedly hydrided and dehydrided without disintegration. A mixture of a finely divided metal hydride and a finely divided matrix metal is contacted with a poison which prevents the metal hydride from dehydriding at room temperature and atmospheric pressure. The mixture of matrix metal and poisoned metal hydride is then compacted under pressure at room temperature to form porous metallic-matrix hydride compacts.

Ron, M.; Gruen, D.M.; Mendelsohn, M.H.; Sheft, I.

1980-01-21T23:59:59.000Z

35

Hydrogen Outgassing from Lithium Hydride  

DOE Green Energy (OSTI)

Lithium hydride is a nuclear material with a great affinity for moisture. As a result of exposure to water vapor during machining, transportation, storage and assembly, a corrosion layer (oxide and/or hydroxide) always forms on the surface of lithium hydride resulting in the release of hydrogen gas. Thermodynamically, lithium hydride, lithium oxide and lithium hydroxide are all stable. However, lithium hydroxides formed near the lithium hydride substrate (interface hydroxide) and near the sample/vacuum interface (surface hydroxide) are much less thermally stable than their bulk counterpart. In a dry environment, the interface/surface hydroxides slowly degenerate over many years/decades at room temperature into lithium oxide, releasing water vapor and ultimately hydrogen gas through reaction of the water vapor with the lithium hydride substrate. This outgassing can potentially cause metal hydriding and/or compatibility issues elsewhere in the device. In this chapter, the morphology and the chemistry of the corrosion layer grown on lithium hydride (and in some cases, its isotopic cousin, lithium deuteride) as a result of exposure to moisture are investigated. The hydrogen outgassing processes associated with the formation and subsequent degeneration of this corrosion layer are described. Experimental techniques to measure the hydrogen outgassing kinetics from lithium hydride and methods employing the measured kinetics to predict hydrogen outgassing as a function of time and temperature are presented. Finally, practical procedures to mitigate the problem of hydrogen outgassing from lithium hydride are discussed.

Dinh, L N; Schildbach, M A; Smith, R A; Balazs1, B; McLean II, W

2006-04-20T23:59:59.000Z

36

Activated aluminum hydride hydrogen storage compositions and ...  

In one aspect, the invention relates to activated aluminum hydride hydrogen storage compositions containing aluminum hydride in the presence of, or absence of ...

37

Generation and purification of maximally entangled atomic states in optical cavities  

Science Conference Proceedings (OSTI)

We present a probabilistic scheme for generating and purifying maximally entangled states of two atoms inside an optical cavity via no-photon detection at the cavity output, where ideal detectors are not required. The intermediate mixed states can be continuously purified so as to violate Bell inequalities in a parametrized manner. The scheme relies on an additional strong-driving field that realizes, atypically, simultaneous Jaynes-Cummings and anti-Jaynes-Cummings interactions.

Lougovski, P.; Walther, H. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany); Solano, E. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany); Seccion Fisica, Departamento de Ciencias, Pontificia Universidad Catolica del Peru, Apartado 1761, Lima (Peru)

2005-01-01T23:59:59.000Z

38

Dimensionally stable metal hydrides - major problem with hydrides is resolved  

SciTech Connect

A patented innovation designed to stabilize metal hydrides and prevent breakbown is described. The innovation is a five step process: reduction of the metal hydride to a particle size less than 10 microns in size; oxidation of particle surfaces; blending of the particles with a porous component and a ballast metal; compression into pellets; calcination of the pellets.

McCarthy, K.

1995-11-01T23:59:59.000Z

39

Dimensionally stable metallic hydride composition  

SciTech Connect

A stable, metallic hydride composition and a process for making such a composition. The composition comprises a uniformly blended mixture of a metal hydride, kieselguhr, and a ballast metal, all in the form of particles. The composition is made by subjecting a metal hydride to one or more hydrogen absorption/desorption cycles to disintegrate the hydride particles to less than approximately 100 microns in size. The particles are partly oxidized, then blended with the ballast metal and the kieselguhr to form a uniform mixture. The mixture is compressed into pellets and calcined. Preferably, the mixture includes approximately 10 vol. % or more kieselguhr and approximately 50 vol. % or more ballast. Metal hydrides that can be used in the composition include Zr, Ti, V, Nb, Pd, as well as binary, tertiary, and more complex alloys of La, Al, Cu, Ti, Co, Ni, Fe, Zr, Mg, Ca, Mn, and mixtures and other combinations thereof. Ballast metals include Al, Cu and Ni.

Heung, Leung K. (Aiken, SC)

1994-01-01T23:59:59.000Z

40

Dimensionally stable metallic hydride composition  

SciTech Connect

A stable, metallic hydride composition and a process for making such a composition are described. The composition comprises a uniformly blended mixture of a metal hydride, kieselguhr, and a ballast metal, all in the form of particles. The composition is made by subjecting a metal hydride to one or more hydrogen absorption/desorption cycles to disintegrate the hydride particles to less than approximately 100 microns in size. The particles are partly oxidized, then blended with the ballast metal and the kieselguhr to form a uniform mixture. The mixture is compressed into pellets and calcined. Preferably, the mixture includes approximately 10 vol. % or more kieselguhr and approximately 50 vol. % or more ballast. Metal hydrides that can be used in the composition include Zr, Ti, V, Nb, Pd, as well as binary, tertiary, and more complex alloys of La, Al, Cu, Ti, Co, Ni, Fe, Zr, Mg, Ca, Mn, and mixtures and other combinations thereof. Ballast metals include Al, Cu and Ni.

Heung, L.K.

1994-03-22T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

A REVIEW OF THE RARE-EARTH HYDRIDES  

SciTech Connect

Some of the properties of rare earth hydrides are reviewed. Information on the hydrides of Tm, Lu, Tb, and Ho is not included because no work has been done on these elements. Eu and Yb are different from other rare earths in that MH/sub 2/ is their highest hydride and the crystal structures of EuH/sub 2/ and YbH/sub 2/ are orthorhombic. ra, Ce, Pr, and Nd form a dihydride which will take hydrogen into solid solution up to MH/sub 3/ without a change in crystal structure. The heavy rare earths form the same type of dihydride as the light, but as the hydrogen content increases from MH/sub 2/ the cubic structure becomes unstable and is replaced by a hexagonal structare. With increasing atomic number, thermal stability and hydrogen deusity increase. (J.R.D.)

Mulford, R.N.R.

1950-01-01T23:59:59.000Z

42

Ground state energy of large atoms in a self-generated magnetic field  

E-Print Network (OSTI)

We consider a large atom with nuclear charge $Z$ described by non-relativistic quantum mechanics with classical or quantized electromagnetic field. We prove that the absolute ground state energy, allowing for minimizing over all possible self-generated electromagnetic fields, is given by the non-magnetic Thomas-Fermi theory to leading order in the simultaneous $Z\\to \\infty$, $\\al\\to 0$ limit if $Z\\al^2\\leq \\kappa$ for some universal $\\kappa$, where $\\al$ is the fine structure constant.

Laszlo Erdos; Jan Philip Solovej

2009-03-10T23:59:59.000Z

43

Asymptotics of the ground state energy for atoms and molecules in the self-generated magnetic field  

E-Print Network (OSTI)

Asymptotics of the ground state energy of the heavy atoms and molecules in the self-generated magnetic field has been derived and for minimal energy positions of nuclei remainder estimate $O(N^{16/9})$ has been recovered.

Ivrii, Victor

2011-01-01T23:59:59.000Z

44

Asymptotics of the ground state energy for atoms and molecules in the self-generated magnetic field  

E-Print Network (OSTI)

Asymptotics of the ground state energy of the heavy atoms and molecules in the self-generated magnetic field has been derived and for minimal energy positions of nuclei remainder estimate $O(N^{16/9})$ has been recovered.

Victor Ivrii

2011-12-23T23:59:59.000Z

45

High-order harmonic generation with Rydberg atoms by using an intense few-cycle pulse  

Science Conference Proceedings (OSTI)

We demonstrate that high-order harmonic generation (HHG) with both high cutoff frequency and high conversion efficiency can be realized by using a Rydberg atom in a few-cycle laser pulse. This is because a Rydberg state has a large electron orbital radius and small binding energy; therefore an electron in the Rydberg state can be ionized easily and accelerated directly toward the core under the interaction of a few-cycle laser pulse, leading to emission of harmonic photons. In this case, the tunneling process of the electron is not involved and, hence, the conversion efficiency and the cutoff frequency of harmonic generation can be higher than that predicted by the conventional three-step model.

Zhai Zhen; Fu Panming; Wang Bingbing [Laboratory of Optical Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China); Zhu Qiren [Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012 (China); Chen Jing [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Yan Zongchao [Department of Physics, University of New Brunswick, P.O. Box 4400, Fredericton, New Brunswick E3B 5A3 (Canada)

2011-04-15T23:59:59.000Z

46

Heat-actuated metal hydride hydrogen compressor testing  

SciTech Connect

Electric utilities use hydrogen for cooling turbine generators. The majority of the utilities purchase the gas from industrial gas markets. On-site electrolytic hydrogen production may prove advantageous both logistically and economically. In order to demonstrate this concept, Public Service Electric and Gas Co. (PSE and G) and EPRI installed an electrolyzer at the Sewaren (NJ) station. To compress the gas, PSE and G purchased a heat-activated metal hydride compressor from Ergenics, Inc. This report describes closed- and open-cycle tests conducted on this metal hydride hydrogen compressor. Test systems, plans, methodologies, and results are presented. A brief discussion evaluates these performance results, addresses some of the practical problems involved with electrolyzer-compressor interface, and compares the costs and benefits of metal hydride versus mechanical hydrogen compression for utility generator cooling.

Piraino, M.; Metz, P.D.; Nienke, J.L.; Freitelberg, A.S.; Rahaman, R.S.

1985-09-01T23:59:59.000Z

47

Light-induced torque for the generation of persistent current flow in atomic gas Bose-Einstein condensates  

SciTech Connect

We show that a persistent current flow in an atomic gas Bose-Einstein condensate could be realized when the system is subject to two counterpropagating Laguerre-Gaussian so-called doughnut beams, creating a toroidal trap. The theory is developed involving a two-photon process within three atomic levels leading to a quantized light-induced torque which rotates the atoms, generating an atomic current flow in the ring. We also show that it is possible for the torque to be controlled and even switched on and off by varying the frequencies of the incident light, thereby allowing a mechanism for the control of the current flow.

Lembessis, V. E. [New York College, 38 Amalias Avenue, GR-105 58, Athens (Greece); Babiker, M. [Department of Physics, University of York, York YO10 5DD (United Kingdom)

2010-11-15T23:59:59.000Z

48

Control of decoherence in the generation of photon pairs from atomic ensembles  

E-Print Network (OSTI)

We report an investigation to establish the physical mechanisms responsible for decoherence in the generation of photon pairs from atomic ensembles, via the protocol of Duan et. al for long distance quantum communication [Nature (London) 414, 413 (2001)] and present the experimental techniques necessary to properly control the process. We develop a theory to model in detail the decoherence process in experiments with magneto-optical traps. The inhomogeneous broadening of the ground state by the trap magnetic field is identified as the principal mechanism for decoherence. In conjunction with our theoretical analysis, we report a series of measurements to characterize and control the coherence time in our experimental setup. We use copropagating stimulated Raman spectroscopy to access directly the ground state energy distribution of the ensemble. These spectroscopic measurements allow us to switch off the trap magnetic field in a controlled way, optimizing the repetition rate for single-photon measurements. With the magnetic field off, we then measure nonclassical correlations for pairs of photons generated by the ensemble as a function of the storage time of the single collective atomic excitation. We report coherence times longer than 10 microseconds, corresponding to an increase of two orders of magnitude compared to previous results in cold ensembles. The coherence time is now two orders of magnitude longer than the duration of the excitation pulses. The comparison between these experimental results and the theory shows good agreement. Finally, we employ our theory to devise ways to improve the experiment by optical pumping to specific initial states.

D. Felinto; C. W. Chou; H. de Riedmatten; S. V. Polyakov; H. J. Kimble

2005-07-13T23:59:59.000Z

49

Erbium hydride decomposition kinetics.  

DOE Green Energy (OSTI)

Thermal desorption spectroscopy (TDS) is used to study the decomposition kinetics of erbium hydride thin films. The TDS results presented in this report are analyzed quantitatively using Redhead's method to yield kinetic parameters (E{sub A} {approx} 54.2 kcal/mol), which are then utilized to predict hydrogen outgassing in vacuum for a variety of thermal treatments. Interestingly, it was found that the activation energy for desorption can vary by more than 7 kcal/mol (0.30 eV) for seemingly similar samples. In addition, small amounts of less-stable hydrogen were observed for all erbium dihydride films. A detailed explanation of several approaches for analyzing thermal desorption spectra to obtain kinetic information is included as an appendix.

Ferrizz, Robert Matthew

2006-11-01T23:59:59.000Z

50

Complex Hydrides for Hydrogen Storage  

DOE Green Energy (OSTI)

This report describes research into the use of complex hydrides for hydrogen storage. The synthesis of a number of alanates, (AIH4) compounds, was investigated. Both wet chemical and mechano-chemical methods were studied.

Slattery, Darlene; Hampton, Michael

2003-03-10T23:59:59.000Z

51

Generating squeezed vacuum field with non-zero orbital angular momentum with atomic ensembles  

E-Print Network (OSTI)

We demonstrated that by using a pump field with non-zero orbital angular momentum (OAM) in the polarization self-rotation squeezing process it is possible to generate a squeezed vacuum optical field with the matching OAM. We found a similar level of maximum quantum noise reduction for a first-order Laguerre-Gaussian pump beam and a regular Gaussian pump beam, even though the optimal operational conditions differed in these two cases. Also, we investigated the effect of self-defocusing on the level of the vacuum squeezing by simultaneously monitoring the minimum quantum noise level and the output beam transverse profile at various pump laser powers and atomic densities, and found no direct correlations between the increased beam size and the degree of measured squeezing.

Mi Zhang; Joseph Soultanis; Irina Novikova; Eugeniy E. Mikhailov

2013-10-21T23:59:59.000Z

52

Generating squeezed vacuum field with non-zero orbital angular momentum with atomic ensembles  

E-Print Network (OSTI)

We demonstrated that by using a pump field with non-zero orbital angular momentum (OAM) in the polarization self-rotation squeezing process it is possible to generate a squeezed vacuum optical field with the matching OAM. We found a similar level of maximum quantum noise reduction for a first-order Laguerre-Gaussian pump beam and a regular Gaussian pump beam, even though the optimal operational conditions differed in these two cases. Also, we investigated the effect of self-defocusing on the level of the vacuum squeezing by simultaneously monitoring the minimum quantum noise level and the output beam transverse profile at various pump laser powers and atomic densities, and found no direct correlations between the increased beam size and the degree of measured squeezing.

Zhang, Mi; Novikova, Irina; Mikhailov, Eugeniy E

2013-01-01T23:59:59.000Z

53

A non-isothermal model of a nickelmetal hydride cell , M. Mohammedb  

E-Print Network (OSTI)

generation during over- charge. Since the metal hydride material gradually loses capacity through usage due KOH solution, which has good electric conductivity for a wide range of temperatures. Some Li

54

Hydride Rim Formation in Unirradiated Zircaloy  

Energy.gov (U.S. Department of Energy (DOE))

The purpose of this work is to develop the means of pre-hydriding unirradiated Zircaloy cladding such that a high concentration, or rim, of hydrides is formed at the cladding outside diameter.

55

Generating conditional atomic entanglement by measuring photon number in a single output channel  

E-Print Network (OSTI)

The polarization analysis of quantized probe light transmitted through an atomic ensemble has been used to prepare entangled collective atomic states. In a "balanced" detection configuration, where the difference signal from two detection ports is analyzed, the continuous monitoring of a component of the Stokes field vector provides a means for conditional projective measurements on the atomic system. Here, we make use of classical driving fields, in the pulsed regime, and of an "unbalanced" detection setup (single detector) where the effective photon number of scattered photons is the detected observable. Conditional atomic spin squeezed states and superpositions of such squeezed states can be prepared in this manner.

Berman, C G P R

2005-01-01T23:59:59.000Z

56

Generating conditional atomic entanglement by measuring photon number in a single output channel  

E-Print Network (OSTI)

The polarization analysis of quantized probe light transmitted through an atomic ensemble has been used to prepare entangled collective atomic states. In a "balanced" detection configuration, where the difference signal from two detection ports is analyzed, the continuous monitoring of a component of the Stokes field vector provides a means for conditional projective measurements on the atomic system. Here, we make use of classical driving fields, in the pulsed regime, and of an "unbalanced" detection setup (single detector) where the effective photon number of scattered photons is the detected observable. Conditional atomic spin squeezed states and superpositions of such squeezed states can be prepared in this manner.

C. Genes P. R. Berman

2005-12-01T23:59:59.000Z

57

Complex Hydrides for Hydrogen Storage  

NLE Websites -- All DOE Office Websites (Extended Search)

Hydrides for Hydrides for Hydrogen Storage George Thomas, Consultant Sandia National Laboratories G. J. Thomas Efficient onboard hydrogen storage is a critical enabling technology for the use of hydrogen in vehicles * The low volumetric density of gaseous fuels requires a storage method which densifies the fuel. - This is particularly true for hydrogen because of its lower energy density relative to hydrocarbon fuels. * Storage methods result in additional weight and volume above that of the fuel. How do we achieve adequate stored energy in an efficient, safe and cost-effective system? G. J. Thomas However, the storage media must meet certain requirements: - reversible hydrogen uptake/release - lightweight - low cost - cyclic stability - rapid kinetic properties - equilibrium properties (P,T) consistent

58

Activated Aluminum Hydride Hydrogen Storage Compositions ...  

Aluminum hydride is the best known alane and has been known for over 60 years. It is potentially a very attractive medium for onboard automotive hydrogen storage ...

59

Phase Field Modeling of Coherent Zirconium Hydrides ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Mechanical properties of hydrided Zircaloy claddings under external load lie in the center of nuclear reactor safety. Numerous experimental...

60

Hydrogen Storage property of sandwiched magnesium hydride naoparticle...  

NLE Websites -- All DOE Office Websites (Extended Search)

Storage property of sandwiched magnesium hydride naoparticle thin film Title Hydrogen Storage property of sandwiched magnesium hydride naoparticle thin film Publication Type...

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Thermal analysis of uranium zirconium hydride fuel using a lead-bismuth gap at LWR operating temperatures  

E-Print Network (OSTI)

Next generation nuclear technology calls for more advanced fuels to maximize the effectiveness of new designs. A fuel currently being studied for use in advanced light water reactors (LWRs) is uranium zirconium hydride ...

Ensor, Brendan M. (Brendan Melvin)

2012-01-01T23:59:59.000Z

62

Diffusional exchange of isotopes in a metal hydride sphere.  

DOE Green Energy (OSTI)

This report describes the Spherical Particle Exchange Model (SPEM), which simulates exchange of one hydrogen isotope by another hydrogen isotope in a spherical metal hydride particle. This is one of the fundamental physical processes during isotope exchange in a bed of spherical metal particles and is thus one of the key components in any comprehensive physics-based model of exchange. There are two important physical processes in the model. One is the entropy of mixing between the two isotopes; the entropy of mixing is increased by having both isotopes randomly placed at interstitial sites on the lattice and thus impedes the exchange process. The other physical process is the elastic interaction between isotope atoms on the lattice. The elastic interaction is the cause for {beta}-phase formation and is independent of the isotope species. In this report the coupled diffusion equations for two isotopes in the {beta}-phase hydride are solved. A key concept is that the diffusion of one isotope depends not only on its concentration gradient, but also on the concentration gradient of the other isotope. Diffusion rate constants and the chemical potentials for deuterium and hydrogen in the {beta}-phase hydride are reviewed because these quantities are essential for an accurate model of the diffusion process. Finally, a summary of some of the predictions from the SPEM model are provided.

Wolfer, Wilhelm G.; Hamilton, John C.; James, Scott Carlton

2011-04-01T23:59:59.000Z

63

Pure superposition states of atoms generated by a bichromatic elliptically polarized filed  

E-Print Network (OSTI)

We find specific polarizations of components of a bichromatic field, which allow one to prepare pure superposition states of atoms, using the coherent population trapping effect. These $m$$-$$m$ states are prepared in the system of Zeeman substates of the ground-state hyperfine levels with arbitrary angular momenta $F_1$ and $F_2$. It is established that, in general case $m\

A. V. Taichenachev; V. I. Yudin; V. L. Velichansky; A. S. Zibrov

2005-03-03T23:59:59.000Z

64

Hydrogen storage technology for metal hydrides  

DOE Green Energy (OSTI)

The advantages of using hydrogen as a secondary energy carrier are stated, and numerous factors pertinent to the technology of hydrogen storage via metal hydrides are briefly described. The technology is centered on iron-titanium hydride, FeTiH/sub x/, as the most practical choice for the safe and compact storage of hydrogen. Uses of hydride hydrogen as a fuel or energy carrier are given. The features of hydride reservoir designs are explained, and some performance data are given for two reservoirs constructed at BNL. Results of tests on the long-term behavior of FeTiH/sub x/ are presented along with information on pressure drop in a hydride bed. Two methods of accommodating hydride expansion are described. Other topics include: container materials selection, safety testing of FeTiH/sub x/, hydride materials development, storage systems work at BNL, the proposed Hydrogen-Halogen Energy Storage System, a proposed technique of storing hydrogen in hollow glass microspheres at very high pressure, and information on the commercial availability of materials and equipment for hydride hydrogen. Current development needs are included in the various sections.

Strickland, G

1978-06-01T23:59:59.000Z

65

Hydrogenation using hydrides and acid  

DOE Patents (OSTI)

The present invention relates to a very rapid, non-catalytic process for hydrogenating unsaturated organic compounds that can be carried out at temperatures generally lower than previously utilized. In this process organic compounds which contain at least one reducible functional group are hydrogenated non-catalytically by reacting them with a hydride complex and a strong acid. The reducible functional group may be, for example, C=C, C-OH, C-O-C, or a strained cyclic structure. If the reactants are not mutually soluble, they are dissolved in an appropriate inert solvent. 3 tabs.

Bullock, R.M.

1989-12-13T23:59:59.000Z

66

Wire Wrapped Hexagonal Pin Arrays for Hydride Fueled PWRs  

E-Print Network (OSTI)

This work contributes to the Hydride Fuels Project, a collaborative effort between UC Berkeley and MIT

Diller, Peter

67

Electrochemical process and production of novel complex hydrides  

SciTech Connect

A process of using an electrochemical cell to generate aluminum hydride (AlH.sub.3) is provided. The electrolytic cell uses a polar solvent to solubilize NaAlH.sub.4. The resulting electrochemical process results in the formation of AlH.sub.3. The AlH.sub.3 can be recovered and used as a source of hydrogen for the automotive industry. The resulting spent aluminum can be regenerated into NaAlH.sub.4 as part of a closed loop process of AlH.sub.3 generation.

Zidan, Ragaiy

2013-06-25T23:59:59.000Z

68

X-Ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin X-Ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin Films Title X-Ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin Films Publication Type Journal Article LBNL Report Number LBNL-50574 Year of Publication 2002 Authors Richardson, Thomas J., Baker Farangis, Jonathan L. Slack, Ponnusamy Nachimuthu, Rupert C. C. Perera, Nobumichi Tamura, and Michael D. Rubin Journal Journal of Alloys and Compounds Volume 356-357 Start Page 204 Pagination 204-207 Date Published 08/2003 Keywords A. hydrogen storage materials, NEXAFS, thin film s; C. EXAFS, x-ray diffraction Abstract Mixed metal thin films containing magnesium and a first-row transition element exhibit very large changes in both reflectance and transmittance on exposure to hydrogen gas. Changes in electronic structure and coordination of the magnesium and transition metal atoms during hydrogen absorption were studied using dynamic in situ transmission mode X-ray absorption spectroscopy. Mg K-edge and Ni, Co, and Ti L-edge spectra reflect both reversible and irreversible changes in the metal environments. A significant shift in the nickel L absorption edge shows it to be an active participant in hydride formation. The effect on cobalt and titanium is much less dramatic, suggesting that these metals act primarily as catalysts for formation of magnesium hydride.

69

Hydrogen-storing hydride complexes  

SciTech Connect

A ternary hydrogen storage system having a constant stoichiometric molar ratio of LiNH.sub.2:MgH.sub.2:LiBH.sub.4 of 2:1:1. It was found that the incorporation of MgH.sub.2 particles of approximately 10 nm to 20 nm exhibit a lower initial hydrogen release temperature of 150.degree. C. Furthermore, it is observed that the particle size of LiBNH quaternary hydride has a significant effect on the hydrogen sorption concentration with an optimum size of 28 nm. The as-synthesized hydrides exhibit two main hydrogen release temperatures, one around 160.degree. C. and the other around 300.degree. C., with the main hydrogen release temperature reduced from 310.degree. C. to 270.degree. C., while hydrogen is first reversibly released at temperatures as low as 150.degree. C. with a total hydrogen capacity of 6 wt. % to 8 wt. %. Detailed thermal, capacity, structural and microstructural properties have been demonstrated and correlated with the activation energies of these materials.

Srinivasan, Sesha S. (Tampa, FL); Niemann, Michael U. (Venice, FL); Goswami, D. Yogi (Tampa, FL); Stefanakos, Elias K. (Tampa, FL)

2012-04-10T23:59:59.000Z

70

Intense multimicrojoule high-order harmonics generated from neutral atoms of In{sub 2}O{sub 3} nanoparticles  

Science Conference Proceedings (OSTI)

We studied high-order harmonic generation from plasma that contains an abundance of indium oxide nanoparticles. We found that harmonics from nanoparticle-containing plasma are considerably more intense than from plasma produced on the In{sub 2}O{sub 3} bulk target, with high-order harmonic energy ranging from 6 {mu}J (for the ninth harmonic) to 1 {mu}J (for the 17th harmonic) in the former case. The harmonic cutoff from nanoparticles was at the 21st order, which is lower than that observed using indium oxide solid target. By comparing the harmonic spectra obtained from solid and nanoparticle indium oxide targets, we concluded that intense harmonics in the latter case are dominantly generated from neutral atoms of the In{sub 2}O{sub 3} nanoparticles.

Elouga Bom, L. B.; Abdul-Hadi, J.; Vidal, F.; Ozaki, T. [Centre Energie, Materiaux et Telecommunications, Institut National de la Recherche Scientifique, 1650 Lionel-Boulet, Varennes, Quebec J3X 1S2 (Canada); Ganeev, R. A. [Centre Energie, Materiaux et Telecommunications, Institut National de la Recherche Scientifique, 1650 Lionel-Boulet, Varennes, Quebec J3X 1S2 (Canada); Scientific Association Akadempribor, Uzbekistan Academy of Sciences, Akademgorodok, Tashkent 100125 (Uzbekistan)

2009-03-16T23:59:59.000Z

71

Chemical Hydride Slurry for Hydrogen Production and Storage  

DOE Green Energy (OSTI)

?\tDuring the investigation of hydriding techniques, we learned that magnesium hydride in a slurry can also be cycled in a rechargeable fashion. Thus, magnesium hydride slurry can act either as a chemical hydride storage medium or as a rechargeable hydride storage system. Hydrogen can be stored and delivered and then stored again thus significantly reducing the cost of storing and delivering hydrogen. Further evaluation and development of this concept will be performed as follow-on work under a

McClaine, Andrew W.

2008-09-30T23:59:59.000Z

72

Liquid suspensions of reversible metal hydrides  

DOE Patents (OSTI)

The reversibility of the process M + x/2 H/sub 2/ ..-->.. MH/sub x/, where M is a metal hydride former that forms a hydride MH/sub x/ in the presence of H/sub 2/, generally used to store and recall H/sub 2/, is found to proceed under a liquid, thereby to reduce contamination, provide better temperature control and provide in situ mobility of the reactants. Thus, a slurry of particles of a metal hydride former with an inert solvent is subjected to temperature and pressure controlled atmosphere containing H/sub 2/, to store hydrogen (at high pressures) and to release (at low pressures) previously stored hydrogen. The direction of the flow of the H/sub 2/ through the liquid is dependent upon the H/sub 2/ pressure in the gas phase at a given temperature. When the former is above the equilibrium absorption pressure of the respective hydride the reaction proceeds to the right, i.e., the metal hydride is formed and hydrogen is stored in the solid particle. When the H/sub 2/ pressure in the gas phase is below the equilibrium dissociation pressure of the respective hydride the reaction proceeds to the left, the metal hydride is decomposed and hydrogen is released into the gas phase.

Reilly, J.J.; Grohse, E.W.; Winsche, W.E.

1983-12-08T23:59:59.000Z

73

Computational Modeling of Uranium Hydriding and Complexes  

DOE Green Energy (OSTI)

Uranium hydriding is one of the most important processes that has received considerable attention over many years. Although many experimental and modeling studies have been carried out concerning thermochemistry, diffusion kinetics and mechanisms of U-hydriding, very little is known about the electronic structure and electronic features that govern the U-hydriding process. Yet it is the electronic feature that controls the activation barrier and thus the rate of hydriding. Moreover the role of impurities and the role of the product UH{sub 3} on hydriding rating are not fully understood. An early study by Condon and Larson concerns with the kinetics of U-hydrogen system and a mathematical model for the U-hydriding process. They proposed that diffusion in the reactant phase by hydrogen before nucleation to form hydride phase and that the reaction is first order for hydriding and zero order for dehydriding. Condon has also calculated and measures the reaction rates of U-hydriding and proposed a diffusion model for the U-hydriding. This model was found to be in excellent agreement with the experimental reaction rates. From the slopes of the Arrhenius plot the activation energy was calculated as 6.35 kcal/mole. In a subsequent study Kirkpatrick formulated a close-form for approximate solution to Condon's equation. Bloch and Mintz have proposed the kinetics and mechanism for the U-H reaction over a wide range of pressures and temperatures. They have discussed their results through two models, one, which considers hydrogen diffusion through a protective UH{sub 3} product layer, and the second where hydride growth occurs at the hydride-metal interface. These authors obtained two-dimensional fits of experimental data to the pressure-temperature reactions. Kirkpatrick and Condon have obtained a linear solution to hydriding of uranium. These authors showed that the calculated reaction rates compared quite well with the experimental data at a hydrogen pressure of 1 atm. Powell et al. have studied U-hydriding in ultrahigh vacuum and obtained the linear rate data over a wide range of temperatures and pressures. They found reversible hydrogen sorption on the UH{sub 3} reaction product from kinetic effects at 21 C. This demonstrates restarting of the hydriding process in the presence of UH{sub 3} reaction product. DeMint and Leckey have shown that Si impurities dramatically accelerate the U-hydriding rates. We report our recent results of relativistic computations that vary from complete active space multi-configuration interaction (CAS-MCSCF) followed by multi-reference configuration interaction (MRSDCI) computations that included up to 50 million configurations for modeling of uranium-hydriding with cluster models will be presented.

Balasubramanian, K; Siekhaus, W J; McLean, W

2003-02-03T23:59:59.000Z

74

New generation polyphase resonant converter-modulators for the Korean atomic energy research institute  

SciTech Connect

This paper will present operational data and performance parameters of the newest generation polyphase resonant high voltage converter modulator (HVCM) as developed and delivered to the KAERI 100 MeV ''PEFP'' accelerator [1]. The KAERI design realizes improvements from the SNS and SLAC designs [2]. To improve the IGBT switching performance at 20 kHz for the KAERI system, the HVCM utilizes the typical zero-voltage-switching (ZVS) at turn on and as well as artificial zero-current-switching (ZCS) at turn-off. The new technique of artificial ZCS technique should result in a 6 fold reduction of IGBT switching losses (3). This improves the HCVM conversion efficiency to better than 95% at full average power, which is 500 kW for the KAERI two klystron 105 kV, 50 A application. The artificial ZCS is accomplished by placing a resonant RLC circuit across the input busswork to the resonant boost transformer. This secondary resonant circuit provides a damped ''kick-back'' to assist in IGBT commutation. As the transformer input busswork is extremely low inductance (< 10 nH), the single RLC network acts like it is across each of the four IGBT collector-emitter terminals of the H-bridge switching network. We will review these topological improvements and the overall system as delivered to the KAERI accelerator and provide details of the operational results.

Reass, William A [Los Alamos National Laboratory; Baca, David M [Los Alamos National Laboratory; Gribble, Robert F [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

75

Design of an Integrated System to Recycle Zircaloy Cladding Using a Hydride-Milling-Dehydride Process  

E-Print Network (OSTI)

A process for recycling spent nuclear fuel cladding, a zirconium alloy (Zircaloy), into a metal powder that may be used for advanced nuclear fuel applications, was investigated to determine if it is a viable strategy. The process begins with hydriding the Zircaloy cladding hulls after the spent nuclear fuel has been dissolved from the cladding. The addition of hydrogen atoms to the zirconium matrix stresses the lattice and forms brittle zirconium hydride, which is easily pulverized into a powder. The dehydriding process removes hydrogen by heating the powder in a vacuum, resulting in a zirconium metal powder. The two main objectives of this research are to investigate the dehydriding process and to design, build and demonstrate a specialized piece of equipment to process the zirconium from cladding hulls to metal powder without intermediate handling. The hydriding process (known from literature) took place in a 95 percent argon - 5 percent hydrogen atmosphere at 500 degrees C while the dehydriding process conditions were researched with a Thermogavimetric Analyzer (TGA). Data from the TGA showed the dehydriding process requires vacuum conditions (~0.001 bar) and 800 degrees C environment to decompose the zirconium hydride. Zirconium metal powder was created in two separate experiments with different milling times, 45 minutes (coarse powder) and 12 hours (fine powder). Both powders were analyzed by three separate analytical methods, X-Ray Diffraction (XRD), size characterization and digital micrographs. XRD analysis proved that the process produced a zirconium metal. Additionally, visual observations of the samples silvery color confirmed the presence of zirconium metal. The presence on zirconium metal in the two samples confirmed the operation of the hydriding / milling / hydriding machine. Further refining of the hydride / milling / dehydride machine could make this process commercially favorable when compared to the high cost of storing nuclear waste and its components. An additional important point is that this process can easily be used on other metals that are subject to hydrogen embrittlement, knowing the relevant temperatures and pressures associated with the hydriding / dehydriding of that particular metal.

Kelley, Randy Dean

2010-08-01T23:59:59.000Z

76

Optimization of hydride fueled pressurized water reactor cores  

E-Print Network (OSTI)

This thesis contributes to the Hydride Fuels Project, a collaborative effort between UC Berkeley and MIT aimed at investigating the potential benefits of hydride fuel use in light water reactors (LWRs). This pursuit involves ...

Shuffler, Carter Alexander

2004-01-01T23:59:59.000Z

77

Thermal hydraulic analysis of hydride fuels in BWR's  

E-Print Network (OSTI)

This thesis contributes to the hydride nuclear fuel project being completed by UC Berkeley and MIT to assess the possible benefits of using hydride fuel in light water nuclear reactors (LWR's). More specifically, this ...

Creighton, John Everett

2005-01-01T23:59:59.000Z

78

Using Metal Hydride to Store Hydrogen  

DOE Green Energy (OSTI)

Hydrogen is the lightest element. At ambient conditions on a volume basis it stores the least amount of energy compared to other fuel carriers such as natural gas and gasoline. For hydrogen to become a practical fuel carrier, a way must be found to increase its volumetric energy density to a practical level. Present techniques being developed include compressed gas, cryogenic liquid and absorbed solid. Each of these techniques has its advantages and disadvantages. And none of them appears to be satisfactory for use in a hydrogen economy. In the interim all of them are used for demonstration purposes. Metal hydrides store hydrogen in a solid form under moderate temperature and pressure that gives them a safety advantage. They require the least amount of energy to operate. Their stored hydrogen density is nearing that of liquid hydrogen. But they are heavy and the weight is their main disadvantage. Current usable metal hydrides can hold no more than about 1.8 percent hydrogen by weight. However much effort is underway to find lighter materials. These include other solid materials other than the traditional metal hydrides. Their operation is expected to be similar to that of metal hydride and can use the technology developed for metal hydrides.

Heung, L.K.

2003-03-12T23:59:59.000Z

79

An Electrolytic Method to Form Zirconium Hydride Phases in Zirconium Alloys with Morphologies Similar to Hydrides Formed in Used Nuclear Fuel  

E-Print Network (OSTI)

An electrolytic cell was designed, built, and tested with several proof-of-concept experiments in which Zircaloy material was charged with hydrogen in order to generate zirconium hydride formations. The Electrolytic Charging with Hydrogen and a Thermal Gradient (ECH-TG) system has the ability to generate static 20C to 120C temperatures for a H2SO4 and H2O bath for isothermal experiment conditions. This system was designed to accommodate a molten salt bath in future experiments to achieve higher isothermal temperatures. Additionally, the design accommodates a cartridge heater, which when placed on the inside of the sample tube, can be set at temperatures up to 350 C and create a thermal gradient across the sample. Finally, a custom LABVIEW VI, L2.vi, was developed to control components and record data during experimentation. This program, along with web cameras and the commercial StirPC software package, enables remote operation for extended periods of time with only minor maintenance during an experiment. While proving the concept for this design, 19 experiments where performed, which form the basis for a future parametric study. Initial results indicate formations of zirconium hydrides which formed rim structures between 8.690 +/- 0.982 ?m and 12.365 +/- 0.635 ?m thick. These electrolytically produced rims were compared with hydrides formed under a previous vapor diffusion experiment via Scanning Electron Microscope (SEM) imaging and Energy dispersive X-ray Spectroscopy (EDS) analysis. While the existing vapor diffusion method formed gradients of zirconium hydride, it failed to produce the gradient in the correct direction and also failed to create a hydride rim. The successful use of the ECH-TG system to create said rim, and some of the methods used to direct that rim to the OD of the tube can be used for future work with the vapor diffusion method in order to create zirconium hydrides of the correct geometry. The procedures and apparatus created for this project represent a reliable method for creating zirconium hydride rim structures.

Kuhr, Samuel Houston

2012-08-01T23:59:59.000Z

80

Hydridable material for the negative electrode in a nickel-metal hydride storage battery  

SciTech Connect

A monophase hydridable material for the negative electrode of a nickel-metal hydride storage battery with a "Lave's phase" structure of hexagonal C14 type (MgZn.sub.2) has the general formula: Zr.sub.1-x Ti.sub.x Ni.sub.a Mn.sub.b Al.sub.c Co.sub.d V.sub.e where ##EQU1##

Knosp, Bernard (Neuilly-sur-Seine, FR); Bouet, Jacques (Paris, FR); Jordy, Christian (Dourdan, FR); Mimoun, Michel (Neuilly-sur-Marne, FR); Gicquel, Daniel (Lanorville, FR)

1997-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Hydrogen isotope exchange in metal hydride columns  

DOE Green Energy (OSTI)

Several metal hydrides were shown to act as chromatographic media for hydrogen isotopes. The procedure was to equilibrate a column of hydride with flowing hydrogen, inject a small quantity of tritium tracer, and observe its elution behavior. Characteristic retention times were found. From these and the extent of widening of the tritium band, the heights equivalent to a theoretical plate could be calculated. Values of around 1 cm were obtained. The following are the metals whose hydrides were studied, together with the temperature ranges in which chromatographic behavior was observed: vanadium, 0 to 70/sup 0/C; zirconium, 500 to 600/sup 0/C; LaNi/sub 5/, -78 to +30/sup 0/C; Mg/sub 2/Ni, 300 to 375/sup 0/C; palladium, 0 to 70/sup 0/C. A dual-temperature isotope separation process based on hydride chromatography was demonstrated. In this, a column was caused to cycle between two temperatures while being supplied with a constant stream of tritium-traced hydrogen. Each half-cycle was continued until ''breakthrough,'' i.e., until the tritium concentration in the effluent was the same as that in the feed. Up to that point, the effluent was enriched or depleted in tritium, by up to 20%.

Wiswall, R; Reilly, J; Bloch, F; Wirsing, E

1977-11-21T23:59:59.000Z

82

Metal hydride fuel storage and method thereof  

DOE Patents (OSTI)

Disclosed herein is a metal hydride fuel storage cartridge having integrated resistive heaters that can be used in conjunction with fuel cells such as MEMS-based fuel cells. The cartridge is fabricated using micromachining methods and thin/thick film materials synthesis techniques.

Morse, Jeffrey D. (Martinez, CA); Jankowski, Alan F. (Livermore, CA); Yu, Conrad (Antioch, CA)

2006-10-17T23:59:59.000Z

83

Development of encapsulated lithium hydride thermal energy storage for space power systems  

DOE Green Energy (OSTI)

Inclusion of thermal energy storage in a pulsed space power supply will reduce the mass of the heat rejection system. In this mode, waste heat generated during the brief high-power burst operation is placed in the thermal store; later, the heat in the store is dissipated to space via the radiator over the much longer nonoperational period of the orbit. Thus, the radiator required is of significantly smaller capacity. Scoping analysis indicates that use of lithium hydride as the thermal storage medium results in system mass reduction benefits for burst periods as long as 800 s. A candidate design for the thermal energy storage component utilizes lithium hydride encapsulated in either 304L stainless steel or molybdenum in a packed-bed configuration with a lithium or sodium-potassium (NaK) heat transport fluid. Key issues associated with the system design include phase-change induced stresses in the shell, lithium hydride and shell compatibility, lithium hydride dissociation and hydrogen loss from the system, void presence and movement associated with the melt-freeze process, and heat transfer limitations on obtaining the desired energy storage density. 58 refs., 40 figs., 11 tabs.

Morris, D.G.; Foote, J.P.; Olszewski, M.

1987-12-01T23:59:59.000Z

84

Internal hydriding in irradiated defected Zircaloy fuel rods: A review (LWBR Development Program)  

DOE Green Energy (OSTI)

Although not a problem in recent commercial power reactors, including the Shippingport Light Water Breeder Reactor, internal hydriding of Zircaloy cladding was a persistent cause of gross cladding failures during the 1960s. It occurred in the fuel rods of water-cooled nuclear power reactors that had a small cladding defect. This report summarizes the experimental findings, causes, mechanisms, and methods of minimizing internal hydriding in defected Zircaloy-clad fuel rods. Irradiation test data on the different types of defected fuel rods, intentionally fabricated defected and in-pile operationally defected rods, are compared. Significant factors affecting internal hydriding in defected Zircaloy-clad fuel rods (defect hole size, internal and external sources of hydrogen, Zircaloy cladding surface properties, nickel alloy contamination of Zircaloy, the effect of heat flux and fluence) are discussed. Pertinent in-pile and out-of-pile test results from Bettis and other laboratories are used as a data base in constructing a qualitative model which explains hydrogen generation and distribution in Zircaloy cladding of defected water-cooled reactor fuel rods. Techniques for minimizing internal hydride failures in Zircaloy-clad fuel rods are evaluated.

Clayton, J C

1987-10-01T23:59:59.000Z

85

Preparation of Prototypic Irradiated Hydrided-Zircaloy Cladding for UFDC Programs  

SciTech Connect

The DOE Used Fuel Disposition Campaign (UFDC) has tasked ORNL to investigate the behavior of light-water-reactor fuel cladding material performance related to extended storage and transportation of used fuel. Fast neutron irradiation of pre-hydrided zirconium-alloy cladding in the High Flux Isotope Reactor (HFIR) at elevated temperatures has been used to simulate the effects of high burnup on used fuel cladding for use in understanding the materials properties relevant to very long-term storage (VLTS) and subsequent transportation. The irradiated pre-hydrided metallic materials will generate baseline data to benchmark hot-cell testing of high-burnup used fuel cladding; and, more importantly, samples free of alpha contamination can be provided to the researchers who do not have hot cell facilities to handle highly contaminated high-burnup used fuel cladding to support their research projects for the UFDC. In order to accomplish this research, ORNL has produced unirradiated zirconium-based cladding tubes with a certain hydrogen concentration. Two capsules (HYCD-1 and HYCD-2) containing hydrided zirconium-based samples, 9.50 mm (0.374 in) in diameter, were inserted in HFIR for neutron irradiation. HYCD-1 was removed after Cycle 440B and HYCD-2 after Cycle 442. This paper will describe the general HYCD experiment configuration, achieved temperatures, and temperature gradients within the cladding, and current results of the PIE of the irradiated hydrided cladding samples.

Ott, Larry J [ORNL] [ORNL; Howard, Richard H [ORNL] [ORNL; Howard, Rob L [ORNL] [ORNL; McDuffee, Joel Lee [ORNL] [ORNL; Yan, Yong [ORNL] [ORNL

2013-01-01T23:59:59.000Z

86

High-order optical harmonic generation as a process of single atom interaction with sub-relativistic single- and multicolor laser fields  

Science Conference Proceedings (OSTI)

We present a non-perturbative theory of a single atom interaction with the multicolor laser field. The theory is based on the use of exact mathematical solutions of the boundary value problem for 'an atom in the external field', as a result the case of arbitrary orientation of atomic angular momentum and electromagnetic wave polarization vector can be described in the consistent mathematical form. We also present the results of numerical simulations on silver and argon atoms interaction with single-and two-color laser fields formed by fundamental frequency and second harmonic of Ti:Sapphire laser. The results of numerical calculations show that the efficiency of high-order harmonic generation (HHG) depends strongly on the laser field parameters (especially on the orientation of polarization vectors and chirp of the two-color laser field components). We have demonstrated the saturation of the cut-off frequency in the laser fields of near-atomic strength and investigated the impact of the field phase in the case of ultrashort laser pulses.

Andreev, A. V.; Stremoukhov, S. Yu.; Shoutova, O. A. [M. V. Lomonosov Moscow State University, physical department, 119991 Leninskie Gory, 1, build. 2, Moscow (Russian Federation)

2012-07-30T23:59:59.000Z

87

The interaction of 193-nm excimer laser radiation with single-crystal zinc oxide: The generation of atomic Zn line emission at laser fluences below breakdown  

SciTech Connect

The production of gas phase atomic and ionic line spectra accompanying the high laser fluence irradiation of solid surfaces is well known and is most often due to the production and interaction of high densities of atoms, ions, and electrons generated from laser-induced breakdown. The resulting plasma expands and moves rapidly away from the irradiated spot and is accompanied by intense emission of light. This type of plume is well studied and is frequently exploited in the technique of chemical analysis known as laser induced breakdown spectroscopy. Here, we describe a similar but weaker emission of light generated in vacuum by the laser irradiation of single crystal ZnO at fluences well below breakdown; this emission consists entirely of optical line emission from excited atomic Zn. We compare the properties of the resulting laser-generated gas-phase light emission (above and below breakdown) and describe a mechanism for the production of the low-fluence optical emission resulting from a fortuitous choice of material and laser wavelength.

Kahn, E. H. [Washington State University, Pullman; Langford, S. C. [Washington State University, Pullman; Dickinson, J. T. [Washington State University, Pullman; Boatner, Lynn A [ORNL

2013-01-01T23:59:59.000Z

88

Recovering hydrogen from gas stream using metal hydride  

SciTech Connect

This invention relates to an improved adiabatic process for separating hydrogen from mixed gas streams using hydridable materials as the absorbing medium. The improvement comprises utilizing a composite comprising a thermal ballast in admixture with the hydride material to absorb the heat of reaction and to aid in desorption. By virtue of the intimate contact of the ballast with the hydridable material rapid cycle times plus good bed utilization are achieved.

Cheng, G.C.; Eisenberg, F.G.; Huston, E.L.; Sandrock, G.D.; Sheridan, J.J.; Snape, E.; Stickles, R.P.

1982-11-23T23:59:59.000Z

89

Dissipative hydride precipitates in superconducting niobium cavities  

Science Conference Proceedings (OSTI)

We report the first direct observation of the microstructural features exhibiting RF losses at high surface magnetic fields of above 100 mT in field emission free superconducting niobium cavities. The lossy areas were identified by advanced thermometry. Surface investigations using different techniques were carried out on cutout samples from lossy areas and showed the presence of dendritic niobium hydrides. This finding has possible implications to the mechanisms of RF losses in superconducting niobium at all field levels.

Romanenko, A.; Cooley, L.D.; /Fermilab; Ciovati, G.; / /Jefferson Lab; Wu, G.; /Argonne

2011-10-01T23:59:59.000Z

90

Metal hydride fuel storage and method thereof - Energy ...  

Disclosed herein is a metal hydride fuel storage cartridge having integrated resistive heaters that can be used in conjunction with fuel cells such as MEMS-based fuel ...

91

Materials compatibility of hydride storage materials with austenitic stainless steels  

DOE Green Energy (OSTI)

This task evaluated the materials compatibility of LaNi[sub 5-x]Al[sub x] (x= 0.3, 0.75) hydrides and palladium coated kieselguhr with austenitic stainless steel in hydrogen and tritium process environments. Based on observations of retired prototype hydride storage beds and materials exposure testing samples designed for this study, no materials compatibility problem was indicated. Scanning electron microscopy observations of features on stainless steel surfaces after exposure to hydrides are also commonly found on as-received materials before hydriding. These features are caused by either normal heat treating and acid cleaning of stainless steel or reflect the final machining operation.

Clark, E.A.

1992-09-21T23:59:59.000Z

92

Materials compatibility of hydride storage materials with austenitic stainless steels  

DOE Green Energy (OSTI)

This task evaluated the materials compatibility of LaNi{sub 5-x}Al{sub x} (x= 0.3, 0.75) hydrides and palladium coated kieselguhr with austenitic stainless steel in hydrogen and tritium process environments. Based on observations of retired prototype hydride storage beds and materials exposure testing samples designed for this study, no materials compatibility problem was indicated. Scanning electron microscopy observations of features on stainless steel surfaces after exposure to hydrides are also commonly found on as-received materials before hydriding. These features are caused by either normal heat treating and acid cleaning of stainless steel or reflect the final machining operation.

Clark, E.A.

1992-09-21T23:59:59.000Z

93

METHOD AND APPARATUS FOR MAKING URANIUM-HYDRIDE COMPACTS  

DOE Patents (OSTI)

A method and apparatus are presented for making compacts of pyrophoric hydrides in a continuous operation out of contact with air. It is particularly useful for the preparation of a canned compact of uranium hydride possessing high density and purity. The metallic uranium is enclosed in a container, positioned in a die body evacuated and nvert the uranium to the hydride is admitted and the container sealed. Heat is applied to bring about the formation of the hydride, following which compression is used to form the compact sealed in a container ready for use.

Wellborn, W.; Armstrong, J.R.

1959-03-10T23:59:59.000Z

94

Development of a Passively Cooled, Electrically Heated Hydride (PACE) Bed  

Science Conference Proceedings (OSTI)

Hydride and Storage / Proceedings of the Sixth International Conference on Tritium Science and Technology Tsukuba, Japan November 12-16, 2001

J. E. Klein; J. R. Brenner; E. F. Dyer

95

Method of making crack-free zirconium hydride  

DOE Patents (OSTI)

Crack-free hydrides of zirconium and zirconium-uranium alloys are produced by alloying the zirconium or zirconium-uranium alloy with beryllium, or nickel, or beryllium and scandium, or nickel and scandium, or beryllium and nickel, or beryllium, nickel and scandium and thereafter hydriding.

Sullivan, Richard W. (Denver, CO)

1980-01-01T23:59:59.000Z

96

Nano-engineering of magnesium hydride for hydrogen storage  

Science Conference Proceedings (OSTI)

The destabilization of magnesium hydride (MgH"2) by solid-state reaction with Si in a nanoscale under vacuum was studied. The nanostructured Si films were deposited on the nanocrystalline MgH"2/Mg composite substrate by the pulsed laser deposition (PLD). ... Keywords: Destabilization, Magnesium hydride, Microstructure, Nano-engineering, Silicon

J. Bystrzycki; T. P?oci?ski; W. Zieli?ski; Z. Winiewski; M. Polanski; W. Mrz; Z. Bojar; K. J. Kurzd?owski

2009-04-01T23:59:59.000Z

97

Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Neutron Irradiation of Hydrided Cladding Material in HFIR Summary Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of Initial Activities Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of Initial Activities Irradiation is known to have a significant impact on the properties and performance of Zircaloy cladding and structural materials (material degradation processes, e.g., effects of hydriding). This UFD study examines the behavior and performance of unirradiated cladding and actual irradiated cladding through testing and simulation. Three capsules containing hydrogen-charged Zircaloy-4 cladding material have been placed in the High Flux Isotope Reactor (HFIR). Irradiation of the capsules was conducted for post-irradiation examination (PIE) metallography. Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of

98

Porous metal hydride composite and preparation and uses thereof  

DOE Patents (OSTI)

A composite formed from large pieces of aggregate formed from (1) metal hydride (or hydride-former) powder and (2) either metal powder or plastic powder or both is prepared. The composite has large macroscopic interconnected pores (much larger than the sizes of the powders which are used) and will have a very fast heat transfer rate and low windage loss. It will be useful, for example, in heat engines, hydrogen storage devices, and refrigerator components which depend for their utility upon both a fast rate of hydriding and dehydriding. Additionally, a method of preparing the composite and a method of increasing the rates of hydriding and dehydriding of metal hydrides are also given.

Steyert, William A. (Los Alamos, NM); Olsen, Clayton E. (Los Alamos, NM)

1982-01-01T23:59:59.000Z

99

Porous metal hydride composite and preparation and uses thereof  

DOE Patents (OSTI)

A composite formed from large pieces of aggregate formed from (1) metal hydride (or hydride-former) powder and (2) either metal powder or plastic powder or both is prepared. The composite has large macroscopic interconnected pores (much larger than the sizes of the powders which are used) and will have a very fast heat transfer rate and low windage loss. It will be useful, for example, in heat engines, hydrogen storage devices, and refrigerator components which depend for their utility upon both a fast rate of hydriding and dehydriding. Additionally, a method of preparing the composite and a method of increasing the rates of hydriding and dehydriding of metal hydrides are also given.

Steyert, W.A.; Olsen, C.E.

1980-03-12T23:59:59.000Z

100

Recent advances in metal hydrides for clean energy applications  

SciTech Connect

Metal hydrides are a fascinating class of materials that can be utilized for a surprising variety of clean energy applications, including smart solar collectors, smart windows, sensors, thermal energy storage, and batteries, in addition to their traditional application for hydrogen storage. Over the past decade, research on metal hydrides for hydrogen storage increased due to global governmental incentives and an increased focus on hydrogen storage research for polymer electrolyte membrane fuel cell operation. Tremendous progress has been made in so-called complex metal hydrides for hydrogen storage applications with the discovery of many new hydrides containing covalently bound complex anions. Many of these materials have applications beyond hydrogen storage and are being investigated for lithium-ion battery separator and anode materials. In this issue of MRS Bulletin , we present the state of the art of key evolving metal-hydride-based clean energy technologies with an outlook toward future needs.

Ronnebro, Ewa; Majzoub, Eric H.

2013-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

On-board hydrogen storage system using metal hydride  

DOE Green Energy (OSTI)

A hydrogen powered hybrid electric bus has been developed for demonstration in normal city bus service in the City of Augusta, Georgia, USA. The development team, called H2Fuel Bus Team, consists of representatives from government, industry and research institutions. The bus uses hydrogen to fuel an internal combustion engine which drives an electric generator. The generator charges a set of batteries which runs the electric bus. The hydrogen fuel and the hybrid concept combine to achieve the goal of near-zero emission and high fuel efficiency. The hydrogen fuel is stored in a solid form using an on-board metal hydride storage system. The system was designed for a hydrogen capacity of 25 kg. It uses the engine coolant for heat to generate a discharge pressure higher than 6 atm. The operation conditions are temperature from ambient to 70 degrees C, hydrogen discharge rate to 6 kg/hr, and refueling time 1.5 hours. Preliminary tests showed that the performance of the on-board storage system exceeded the design requirements. Long term tests have been planned to begin in 2 months. This paper discusses the design and performance of the on-board hydrogen storage system.

Heung, L.K.

1997-07-01T23:59:59.000Z

102

Modular hydride beds for mobile applications  

DOE Green Energy (OSTI)

Design, construction, initial testing and simple thermal modeling of modular, metal hydride beds have been completed. Originally designed for supplying hydrogen to a fuel cell on a mobile vehicle, the complete bed design consists of 8 modules and is intended for use on the Palm Desert Vehicle (PDV) under development at the Schatz Energy Center, Humbolt State University. Each module contains approximately 2 kg of a commercially available, low temperature, hydride-forming metal alloy. Waste heat from the fuel cell in the form of heated water is used to desorb hydrogen from the alloy for supplying feed hydrogen to the fuel cell. In order to help determine the performance of such a modular bed system, six modules were constructed and tested. The design and construction of the modules is described in detail. Initial testing of the modules both individually and as a group showed that each module can store {approximately} 30 g of hydrogen (at 165 PSIA fill pressure, 17 C), could be filled with hydrogen in 6 minutes at a nominal, 75 standard liters/min (slm) fueling rate, and could supply hydrogen during desorption at rates of 25 slm, the maximum anticipated hydrogen fuel cell input requirement. Tests made of 5 modules as a group indicated that the behavior of the group run in parallel both in fueling and gas delivery could be directly predicted from the corresponding, single module characteristics by using an appropriate scaling factor. Simple thermal modeling of a module as an array of cylindrical, hydride-filled tubes was performed. The predictions of the model are in good agreement with experimental data.

Malinowski, M.E.; Stewart, K.D.

1997-08-01T23:59:59.000Z

103

OPTIMIZATION OF INTERNAL HEAT EXCHANGERS FOR HYDROGEN STORAGE TANKS UTILIZING METAL HYDRIDES  

DOE Green Energy (OSTI)

Two detailed, unit-cell models, a transverse fin design and a longitudinal fin design, of a combined hydride bed and heat exchanger are developed in COMSOL{reg_sign} Multiphysics incorporating and accounting for heat transfer and reaction kinetic limitations. MatLab{reg_sign} scripts for autonomous model generation are developed and incorporated into (1) a grid-based and (2) a systematic optimization routine based on the Nelder-Mead downhill simplex method to determine the geometrical parameters that lead to the optimal structure for each fin design that maximizes the hydrogen stored within the hydride. The optimal designs for both the transverse and longitudinal fin designs point toward closely-spaced, small cooling fluid tubes. Under the hydrogen feed conditions studied (50 bar), a 25 times improvement or better in the hydrogen storage kinetics will be required to simultaneously meet the Department of Energy technical targets for gravimetric capacity and fill time. These models and methodology can be rapidly applied to other hydrogen storage materials, such as other metal hydrides or to cryoadsorbents, in future work.

Garrison, S.; Tamburello, D.; Hardy, B.; Anton, D.; Gorbounov, M.; Cognale, C.; van Hassel, B.; Mosher, D.

2011-07-14T23:59:59.000Z

104

Chemical Hydride Slurry for Hydrogen Production and Storage  

Science Conference Proceedings (OSTI)

The purpose of this project was to investigate and evaluate the attractiveness of using a magnesium chemical hydride slurry as a hydrogen storage, delivery, and production medium for automobiles. To fully evaluate the potential for magnesium hydride slurry to act as a carrier of hydrogen, potential slurry compositions, potential hydrogen release techniques, and the processes (and their costs) that will be used to recycle the byproducts back to a high hydrogen content slurry were evaluated. A 75% MgH2 slurry was demonstrated, which was just short of the 76% goal. This slurry is pumpable and storable for months at a time at room temperature and pressure conditions and it has the consistency of paint. Two techniques were demonstrated for reacting the slurry with water to release hydrogen. The first technique was a continuous mixing process that was tested for several hours at a time and demonstrated operation without external heat addition. Further work will be required to reduce this design to a reliable, robust system. The second technique was a semi-continuous process. It was demonstrated on a 2 kWh scale. This system operated continuously and reliably for hours at a time, including starts and stops. This process could be readily reduced to practice for commercial applications. The processes and costs associated with recycling the byproducts of the water/slurry reaction were also evaluated. This included recovering and recycling the oils of the slurry, reforming the magnesium hydroxide and magnesium oxide byproduct to magnesium metal, hydriding the magnesium metal with hydrogen to form magnesium hydride, and preparing the slurry. We found that the SOM process, under development by Boston University, offers the lowest cost alternative for producing and recycling the slurry. Using the H2A framework, a total cost of production, delivery, and distribution of $4.50/kg of hydrogen delivered or $4.50/gge was determined. Experiments performed at Boston University have demonstrated the technical viability of the process and have provided data for the cost analyses that have been performed. We also concluded that a carbothermic process could also produce magnesium at acceptable costs. The use of slurry as a medium to carry chemical hydrides has been shown during this project to offer significant advantages for storing, delivering, and distributing hydrogen: Magnesium hydride slurry is stable for months and pumpable. The oils of the slurry minimize the contact of oxygen and moisture in the air with the metal hydride in the slurry. Thus reactive chemicals, such as lithium hydride, can be handled safely in the air when encased in the oils of the slurry. Though magnesium hydride offers an additional safety feature of not reacting readily with water at room temperatures, it does react readily with water at temperatures above the boiling point of water. Thus when hydrogen is needed, the slurry and water are heated until the reaction begins, then the reaction energy provides heat for more slurry and water to be heated. The reaction system can be relatively small and light and the slurry can be stored in conventional liquid fuel tanks. When transported and stored, the conventional liquid fuel infrastructure can be used. The particular metal hydride of interest in this project, magnesium hydride, forms benign byproducts, magnesium hydroxide (Milk of Magnesia) and magnesium oxide. We have estimated that a magnesium hydride slurry system (including the mixer device and tanks) could meet the DOE 2010 energy density goals. ? During the investigation of hydriding techniques, we learned that magnesium hydride in a slurry can also be cycled in a rechargeable fashion. Thus, magnesium hydride slurry can act either as a chemical hydride storage medium or as a rechargeable hydride storage system. Hydrogen can be stored and delivered and then stored again thus significantly reducing the cost of storing and delivering hydrogen. Further evaluation and development of this concept will be performed as follow-on work under a

McClaine, Andrew W.

2008-09-30T23:59:59.000Z

105

ENVIRONMENTAL REACTIVITY OF SOLID STATE HYDRIDE MATERIALS  

DOE Green Energy (OSTI)

In searching for high gravimetric and volumetric density hydrogen storage systems, it is inevitable that higher energy density materials will be used. In order to make safe and commercially acceptable condensed phase hydrogen storage systems, it is important to understand quantitatively the risks involved in using and handling these materials and to develop appropriate mitigation strategies to handle potential material exposure events. A crucial aspect of the development of risk identification and mitigation strategies is the development of rigorous environmental reactivity testing standards and procedures. This will allow for the identification of potential risks and implementation of risk mitigation strategies. Modified testing procedures for shipping air and/or water sensitive materials, as codified by the United Nations, have been used to evaluate two potential hydrogen storage materials, 2LiBH{sub 4} {center_dot} MgH{sub 2} and NH{sub 3}BH{sub 3}. The modified U.N. procedures include identification of self-reactive substances, pyrophoric substances, and gas-emitting substances with water contact. The results of these tests for air and water contact sensitivity will be compared to the pure material components where appropriate (e.g. LiBH{sub 4} and MgH{sub 2}). The water contact tests are divided into two scenarios dependent on the hydride to water mole ratio and heat transport characteristics. Air contact tests were run to determine whether a substance will spontaneously react with air in a packed or dispersed form. In the case of the 2LiBH{sub 4} {center_dot} MgH{sub 2} material, the results from the hydride mixture compared to the pure materials results showed the MgH{sub 2} to be the least reactive component and LiBH{sub 4} the more reactive. The combined 2LiBH{sub 4} {center_dot} MgH{sub 2} resulted in a material having environmental reactivity between these two materials. Relative to 2LiBH{sub 4} {center_dot} MgH{sub 2}, the chemical hydride NH{sub 3}BH{sub 3} was observed to be less environmentally reactive.

Gray, J; Donald Anton, D

2009-04-23T23:59:59.000Z

106

The Hydriding Kinetics of Organic Hydrogen Getters  

DOE Green Energy (OSTI)

The aging of hermetically sealed systems is often accompanied by the gradual production of hydrogen gas that is a result of the decay of environmental gases and the degradation of organic materials. In particular, the oxygen, water, hydrogen ''equilibrium'' is affected by the removal of oxygen due the oxidation of metals and organic materials. This shift of the above ''equilibrium'' towards the formation of hydrogen gas, particularly in crevices, may eventually reach an explosive level of hydrogen gas or degrade metals by hydriding them. The latter process is generally delayed until the oxidizing species are significantly reduced. Organic hydrogen getters introduced by Allied Signal Aerospace Company, Kansas City Division have proven to be a very effective means of preventing hydrogen gas accumulation in sealed containers. These getters are relatively unaffected by air and environmental gases. They can be packaged in a variety of ways to fit particular needs such as porous pellets, fine or coarse [gravel] powder, or loaded into silicone rubber. The hydrogen gettering reactions are extremely irreversible since the hydrogen gas is converted into an organic hydrocarbon. These getters are based on the palladium-catalyzed hydrogenation of triple bonds to double and then single bonds in aromatic aryl compounds. DEB (1,4 bis (phenyl ethynyl) benzene) typically mixed with 25% by weight carbon with palladium (1% by weight of carbon) is one of the newest and best of these organic hydrogen getters. The reaction mechanisms are complex involving solid state reaction with a heterogeneous catalyst leading to the many intermediates, including mixed alkyl and aryl hydrocarbons with the possibilities of many isomers. The reaction kinetics mechanisms are also strongly influenced by the form in which they are packaged. For example, the hydriding rates for pellets and gravel have a strong dependence on reaction extent (i.e., DEB reduction) and a kinetic order in pressure of 0.76. Silicone rubber based DEB getters hydride at a much lower rate, have little dependence on reaction extent, have a higher kinetic order in pressure (0.87), and have a lower activation energy. The kinetics of the reaction as a function of hydrogen pressure, stoichiometry, and temperature for hydrogen and deuterium near ambient temperature (0 to 75 C) for pressures near or below 100 Pa over a wide range (in some cases, the complete) hydrogenation range are presented along with multi-dimensional rate models.

Powell, G. L.

2002-02-11T23:59:59.000Z

107

Advanced nickel-metal hydride cell development. Final report, September 1993--March 1996  

DOE Green Energy (OSTI)

Inert gas atomization using metal hydride alloys for a Ni/MH{sub x}cell was studied. Atomization of the alloys was demonstrated on a small production scale up to batch size of several kg. Relative performance of the atomized and nonatomized alloys was investigated for the electrode material in a Ni/MH{sub x} cell. The study included effects of charge-discharge rates, temperature, and particle size on cell voltage (polarization) and specific capacity. Results show that the specific capacity of the present atomized alloys was apprecialy smaller than that of the nonatomized powder, especially for initial cycles. Full activation of the atomized alloys oftentook several hundreds of cycles. However, no appreciable difference in discharge rate capability was observed with R10 and R12 alloys. Chemical compositions were indistinguishable, although the oxygen contents of the atomized alloys were always higher. Effects of Ni and Cu coating on alloy performance were studied after electroless coating; the coatings noticeably improved the electrode rate capability for all the alloys. The electrode polarization was esecially improved, but not the cycle life. Further studies are needed.

Lim, Hong S.

1996-03-01T23:59:59.000Z

108

Use of Solid Hydride Fuel for Improved long-Life LWR Core Designs  

Science Conference Proceedings (OSTI)

The primary objective of this project was to assess the feasibility of improving the performance of PWR and BWR cores by using solid hydride fuels instead of the commonly used oxide fuel. The primary measure of performance considered is the bus-bar cost of electricity (COE). Additional performance measures considered are safety, fuel bundle design simplicity in particular for BWRs, and plutonium incineration capability. It was found that hydride fuel can safely operate in PWRs and BWRs without restricting the linear heat generation rate of these reactors relative to that attainable with oxide fuel. A couple of promising applications of hydride fuel in PWRs and BWRs were identified: (1) Eliminating dedicated water moderator volumes in BWR cores thus enabling to significantly increase the cooled fuel rods surface area as well as the coolant flow cross section area in a given volume fuel bundle while significantly reducing the heterogeneity of BWR fuel bundles thus achieving flatter pin-by-pin power distribution. The net result is a possibility to significantly increase the core power density on the order of 30% and, possibly, more, while greatly simplifying the fuel bundle design. Implementation of the above modifications is, though, not straightforward; it requires a design of completely different control system that could probably be implemented only in newly designed plants. It also requires increasing the coolant pressure drop across the core. (2) Recycling plutonium in PWRs more effectively than is possible with oxide fuel by virtue of a couple of unique features of hydride fuel reduced inventory of U-238 and increased inventory of hydrogen. As a result, the hydride fuelled core achieves nearly double the average discharge burnup and the fraction of the loaded Pu it incinerates in one pass is double that of the MOX fuel. The fissile fraction of the Pu in the discharged hydride fuel is only ~2/3 that of the MOX fuel and the discharged hydride fuel is more proliferation resistant. Preliminary feasibility assessment indicates that by replacing some of the ZrH1.6 by ThH2 it will be possible to further improve the plutonium incineration capability of PWRs. Other possibly promising applications of hydride fuel were identified but not evaluated in this work. A number of promising oxide fueled PWR core designs were also found as spin-offs of this study: (1) The optimal oxide fueled PWR core design features smaller fuel rod diameter of D=6.5 mm and a larger pitch-to-diameter ratio of P/D=1.39 than presently practiced by industry 9.5mm and 1.326. This optimal design can provide a 30% increase in the power density and a 24% reduction in the cost of electricity (COE) provided the PWR could be designed to have the coolant pressure drop across the core increased from the reference 29 psia to 60 psia. (2) Using wire wrapped oxide fuel rods in hexagonal fuel assemblies it is possible to design PWR cores to operate at 54% higher power density than the reference PWR design that uses grid spacers and a square lattice, provided 60 psia coolant pressure drop across the core could be accommodated. Uprating existing PWRs to use such cores could result in 40% reduction in the COE. The optimal lattice geometry is D = 8.08 mm and P/D = 1.41. The most notable advantages of wire wraps over grid spacers are their significant lower pressure drop, higher critical heat flux and improved vibrations characteristics.

Greenspan, E

2006-04-30T23:59:59.000Z

109

A new phase in palladium hydride technology  

DOE Green Energy (OSTI)

Two plateaux are observed in both the absorption and desorption isotherms of palladium hydride. For the absorption isotherm, a change in plateau pressure is observed at a hydrogen-to-metal (H/M) ratio of about 0.35 for all temperatures studied. For the desorption isotherm, the change in plateau pressure appears to be a function of temperature, ranging from an H/M ratio of 0.18 at 80{degrees}C to 0.3 at 140{degrees}C. These data are interpreted as being experimentally observed boundaries to an equilibrium phase line located in the miscibility gap of the palladium/hydrogen phase diagram. This new phase does not appear to be a stoichiometric compounds, but rather its composition seems to vary with temperature. 6 refs., 4 figs.

Walters, R.T.

1991-12-31T23:59:59.000Z

110

A new phase in palladium hydride technology  

DOE Green Energy (OSTI)

Two plateaux are observed in both the absorption and desorption isotherms of palladium hydride. For the absorption isotherm, a change in plateau pressure is observed at a hydrogen-to-metal (H/M) ratio of about 0.35 for all temperatures studied. For the desorption isotherm, the change in plateau pressure appears to be a function of temperature, ranging from an H/M ratio of 0.18 at 80{degrees}C to 0.3 at 140{degrees}C. These data are interpreted as being experimentally observed boundaries to an equilibrium phase line located in the miscibility gap of the palladium/hydrogen phase diagram. This new phase does not appear to be a stoichiometric compounds, but rather its composition seems to vary with temperature. 6 refs., 4 figs.

Walters, R.T.

1991-01-01T23:59:59.000Z

111

Hydrogen storage in sodium aluminum hydride.  

DOE Green Energy (OSTI)

Sodium aluminum hydride, NaAlH{sub 4}, has been studied for use as a hydrogen storage material. The effect of Ti, as a few mol. % dopant in the system to increase kinetics of hydrogen sorption, is studied with respect to changes in lattice structure of the crystal. No Ti substitution is found in the crystal lattice. Electronic structure calculations indicate that the NaAlH{sub 4} and Na{sub 3}AlH{sub 6} structures are complex-ionic hydrides with Na{sup +} cations and AlH{sub 4}{sup -} and AlH{sub 6}{sup 3-} anions, respectively. Compound formation studies indicate the primary Ti-compound formed when doping the material at 33 at. % is TiAl{sub 3} , and likely Ti-Al compounds at lower doping rates. A general study of sorption kinetics of NaAlH{sub 4}, when doped with a variety of Ti-halide compounds, indicates a uniform response with the kinetics similar for all dopants. NMR multiple quantum studies of solution-doped samples indicate solvent interaction with the doped alanate. Raman spectroscopy was used to study the lattice dynamics of NaAlH{sub 4}, and illustrated the molecular ionic nature of the lattice as a separation of vibrational modes between the AlH{sub 4}{sup -} anion-modes and lattice-modes. In-situ Raman measurements indicate a stable AlH{sub 4}{sup -} anion that is stable at the melting temperature of NaAlH{sub 4}, indicating that Ti-dopants must affect the Al-H bond strength.

Ozolins, Vidvuds; Herberg, J.L. (Lawrence Livermore National Laboratories, Livermore, CA); McCarty, Kevin F.; Maxwell, Robert S. (Lawrence Livermore National Laboratories, Livermore, CA); Stumpf, Roland Rudolph; Majzoub, Eric H.

2005-11-01T23:59:59.000Z

112

Steps to Commercialization: Nickel Metal Hydride Batteries | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Steps to Commercialization: Nickel Metal Hydride Batteries Steps to Commercialization: Nickel Metal Hydride Batteries Steps to Commercialization: Nickel Metal Hydride Batteries October 17, 2011 - 10:42am Addthis Steps to Commercialization: Nickel Metal Hydride Batteries Matthew Loveless Matthew Loveless Data Integration Specialist, Office of Public Affairs How does it work? Through licensing and collaborative work, Energy Department-sponsored research can yield great economic benefits and help bring important new products to market. The Energy Department funds cutting-edge research on a broad range of topics ranging from advanced battery construction to the modeling of industrial processes and supercomputer simulation of supernovae. But this research is not only about furthering our understanding of the world around

113

Nonaqueous actinide hydride dissolution and production of actinide $beta$- diketonates  

DOE Patents (OSTI)

Actinide beta-diketonate complex molecular compounds are produced by reacting a beta-diketone compound with a hydride of the actinide material in a mixture of carbon tetrachloride and methanol. (auth)

Crisler, L.R.

1975-11-11T23:59:59.000Z

114

Transient analysis of hydride fueled pressurized water reactor cores  

E-Print Network (OSTI)

This thesis contributes to the hydride nuclear fuel project led by U. C. Berkeley for which MIT is to perform the thermal hydraulic and economic analyses. A parametric study has been performed to determine the optimum ...

Trant, Jarrod Michael

2004-01-01T23:59:59.000Z

115

Metal hydrides: Relevant Materials for Lithium-ion Batteries ...  

Science Conference Proceedings (OSTI)

Reactivity of MgH2 with lithium is a reversible conversion reaction (reversible capacity of 1500 mAh/g) generalized to many hydrides as: MHx + xLi+ + xe- ? M +...

116

Development of the Low-Pressure Hydride/Dehydride Process  

DOE Green Energy (OSTI)

The low-pressure hydride/dehydride process was developed from the need to recover thin-film coatings of plutonium metal from the inner walls of an isotope separation chamber located at Los Alamos and to improve the safety operation of a hydride recovery process using hydrogen at a pressure of 0.7 atm at Rocky Flats. This process is now the heart of the Advanced Recovery and Integrated Extraction System (ARIES) project.

Rueben L. Gutierrez

2001-04-01T23:59:59.000Z

117

Optimization of Hydride Rim Formation in Unirradiated Zr 4 Cladding  

Science Conference Proceedings (OSTI)

The purpose of this work is to build on the results reported in the M2 milestone M2FT 13PN0805051, document number FCRD-USED-2013-000151 (Hanson, 2013). In that work, it was demonstrated that unirradiated samples of zircaloy-4 cladding could be pre-hydrided at temperatures below 400C in pure hydrogen gas and that the growth of hydrides on the surface could be controlled by changing the surface condition of the samples and form a desired hydride rim on the outside diameter of the cladding. The work performed at Pacific Northwest National Laboratory since the issuing of the M2 milestone has focused its efforts to optimize the formation of a hydride rim on available zircaloy-4 cladding samples by controlling temperature variation and gas flow control during pre-hydriding treatments. Surface conditioning of the outside surface was also examined as a variable. The results of test indicate that much of the variability in the hydride thickness is due to temperature variation occurring in the furnaces as well as how hydrogen gas flows across the sample surface. Efforts to examine other alloys, gas concentrations, and different surface conditioning plan to be pursed in the next FY as more cladding samples become available

Shimskey, Rick W.; Hanson, Brady D.; MacFarlan, Paul J.

2013-09-30T23:59:59.000Z

118

Electronic structure, bonding and chemisorption in metallic hydrides  

DOE Green Energy (OSTI)

Problems that can arise during the cycling steps for a hydride storage system usually involve events at surfaces. Chemisorption and reaction processes can be affected by small amounts of contaminants that may act as catalytic poisons. The nature of the poisoning process can vary greatly for the different metals and alloys that form hydrides. A unifying concept is offered, which satisfactorily correlates many of the properties of transition-metal, rare-earth and actinide hydrides. The metallic hydrides can be differentiated on the basis of electronegativity, metallic radius (valence) and electronic structure. For those systems where there are d (transition metals) or f (early actinides) electrons near the Fermi level a broad range of chemical and catalytic behaviors are found, depending on bandwidth and energy. The more electropositive metals (rare-earths, actinides, transition metals with d < 5) tend to strongly chemisorb electrophilic molecules; this is a consequence of the manner in which new bonding states are introduced. More electronegative metals (d >> 5) dissolve hydrogen and form hydrides by an electronically somewhat different process, and as a class tend to adsorb electrophobic molecules. The net charge-transfer in either situation is subtle; however, the small differences are responsible for many of the observed structural, chemical, and catalytic properties in these hydride systems.

Ward, J.W.

1980-01-01T23:59:59.000Z

119

Feasibility study for the recycling of nickel metal hydride electric vehicle batteries. Final report  

DOE Green Energy (OSTI)

This feasibility study examined three possible recycling processes for two compositions (AB{sub 2} and AB{sub 5}) of nickel metal hydride electric vehicle batteries to determine possible rotes for recovering battery materials. Analysts examined the processes, estimated the costs for capital equipment and operation, and estimated the value of the reclaimed material. They examined the following three processes: (1) a chemical process that leached battery powders using hydrochloric acid, (2) a pyrometallurical process, and (3) a physical separation/chemical process. The economic analysis revealed that the physical separation/chemical process generated the most revenue.

Sabatini, J.C.; Field, E.L.; Wu, I.C.; Cox, M.R.; Barnett, B.M.; Coleman, J.T. [Little (Arthur D.), Inc., Cambridge, MA (United States)

1994-01-01T23:59:59.000Z

120

The Universe Adventure - Atoms  

NLE Websites -- All DOE Office Websites (Extended Search)

Matter and Atoms Matter and Atoms Richard Feynman "If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generations of creatures, what statement would contain the most information in the fewest words? I believe it is that...all things are made of atoms." -Richard P. Feynman, winner of the 1965 Nobel Prize in Physics All is atoms Matter is made of atoms, and atoms are comprised of protons, neutrons, and electrons. Everything in the Universe is made of matter. Though matter exists in many different forms, each form is made out of the same basic constituents: small particles called atoms. Atoms themselves are made of smaller particles: protons, neutrons, and electrons. Protons and neutrons are composed of even smaller particles called quarks.

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

REACTION KINETICS AND X-RAY ABSORPTION SPECTROSCOPY STUDIES OF YTTRIUM CONTAINING METAL HYDRIDE ELECTRODES  

DOE Green Energy (OSTI)

This was a study of electrode degradation mechanisms and the reaction kinetics of LaNi{sub 4.7}Sn{sub 0.3}, La{sub (1{minus}x)}, (x = 0.1, 0.2, and 0.3) and La{sub 0.7}Y{sub 0.3}Ni{sub 4.6}Sn{sub 0.3}Co{sub 0.1} metal hydride electrodes. Alloy characterization included x-ray diffraction (XRD), x-ray absorption (XAS), hydrogen absorption in a Sieverts apparatus, and electrochemical cycling of alloy electrodes. The atomic volume of H was determined for two of the alloys. Electrochemical kinetic measurements were made using steady state galvanostatic measurements, galvanodynamic sweep, and electrochemical impedance techniques. XAS was used to examine the degree of corrosion of the alloys with cycling. Alloying with Y decreased the corrosion rate. The results are consistent with corrosion inhibition by a Y containing passive film. The increase in the kinetics of the hydrogen oxidation reaction (HOR) with increasing depth of discharge was much greater on the Y containing alloys. This may be due to the dehydriding of the catalytic species on the surface of the metal hydride particles.

TICIANELLI,E.A.; MUKERJEE,S.; MCBREEN,J.; ADZIC,G.D.; JOHNSON,J.R.; REILLY,J.J.

1998-11-01T23:59:59.000Z

122

Synthesis and characterization of metal hydride/carbon aerogel composites for hydrogen storage  

Science Conference Proceedings (OSTI)

Two materials currently of interest for onboard lightweight hydrogen storage applications are sodium aluminum hydride (NaAlH4), a complex metal hydride, and carbon aerogels (CAs), a light porous material connected by several spherical nanoparticles. ...

Kuen-Song Lin; Yao-Jen Mai; Su-Wei Chiu; Jing-How Yang; Sammy L. I. Chan

2012-01-01T23:59:59.000Z

123

Synthesis and small molecule chemistry of the niobaziridine-hydride functional group  

E-Print Network (OSTI)

Chapter 1. Synthesis and Divergent Reactivity of the Niobaziridine-Hydride Functional Group The synthesis, characterization and reactivity of the niobaziridine-hydride complex Nb(H)([eta]-t- ]Bu(H)C=NAr)(N[Np]Ar)? (la-H; ...

Figueroa, Joshua S

2005-01-01T23:59:59.000Z

124

THE EFFECT OF 3HE ON LOW PRESSURE HYDRIDE ABSORPTION MEASUREMENTS WITH TRITIUM  

DOE Green Energy (OSTI)

Absorption isotherm data exists for a wide variety of hydrogen-metal systems. When working with high purity gases, appropriately sized equipment, and hydrides with equilibrium pressures above several hundred Pa, data collection is relatively straightforward. Special consideration must be given to experiments involving low equilibrium pressure hydrides, as even sub-ppm levels of gas impurities can generate partial pressures many times greater than the equilibrium pressures to be measured. Tritium absorption experiments are further complicated by the continuous generation of helium-3. The time required to transfer and absorb a known quantity of tritium onto a sample ultimately limits the minimum pressure range that can be studied using the standard technique. Equations are presented which show the pressure of helium-3 in a sample cell based on the amount of tritium to be absorbed, the sample cell volume and temperature, and the decay time of tritium. Sample calculations for zirconium show that at 300 C, the estimated helium-3 pressure in the cell will be equal to the hydrogen absorption pressure after only milliseconds of tritium decay. An alternate method is presented that permits the collection of equilibrium data at pressures orders of magnitude lower than possible using a direct approach.

Staack, G.; Klein, J.

2011-01-20T23:59:59.000Z

125

X-RAY ABSORPTION SPECTROSCOPY OF TRANSITION METAL-MAGNESIUM HYDRIDE FILMS  

NLE Websites -- All DOE Office Websites (Extended Search)

Spectroscopy of Transition Metal-Magnesium Spectroscopy of Transition Metal-Magnesium Hydride Thin Films T. J. Richardson a, *, B. Farangis a , J. L. Slack a , P. Nachimuthu b , R. Pereira b , N. Tamura b , and M. Rubin a a Environmental Energy Technologies Division, b Advanced Light Source, Ernest Orlando Lawrence Berkeley National Laboratory Berkeley, California 94720, USA *Corresponding author, E-mail address: tjrichardson@lbl.gov Abstract Mixed metal thin films containing magnesium and a first-row transition element exhibit very large changes in both reflectance and transmittance on exposure to hydrogen gas. Changes in electronic structure and coordination of the magnesium and transition metal atoms during hydrogen absorption were studied using dynamic in situ transmission mode X-ray absorption

126

Progress in the development of Ovonic nickel-metal hydride batteries  

SciTech Connect

Proprietary, multicomponent hydrogen storage alloys using the principles of atomic engineering form the heart of Ovonic Nickel-Metal Hydride (Ni/MH) battery technology. This battery system, in development for 10 years, has been licensed to several manufacturers both for consumer cells and electric vehicle batteries. These cells have achieved a specific energy of over 80 Wh/kg, a peak power in excess of 200 W/kg, and over 1000 cycles at 100% depth of discharge. They also have an intrinsic ability to withstand overcharge and overdischarge abuse. Ovonic Ni/MH batteries are environmentally friendly and can be recycled. Performance data will be presented showing the successful scale-up of this technology for electric vehicle applications.

Venkatesan, S.; Corrigan, D.A.; Gifford, P.R.; Fetcenko, M.A.; Dhar, S.K.; Ovshinsky, S.R. (Ovonic Battery Co., Troy, MI (United States))

1993-05-01T23:59:59.000Z

127

Magnetic properties and crystal structure of RENiA1 and UniA1 hydrides.  

DOE Green Energy (OSTI)

RENiAl (RE = rare-earth metal) and UNiAl compounds crystallizing in the hexagonal ZrNiAl-type structure (space group P{bar 6}2m) can absorb up to 2 and 3 hydrogen (deuterium) atoms per formula unit, respectively. Hydrogenation leads to a notable lattice expansion and modification of magnetic properties. However, the impact of hydrogenation on magnetism is the opposite for 4f- and 5f-materials: TN(T{sub c})is lowered in the case of rare-earth hydrides, while for UNiAlH(D){sub x} it increases by an order of magnitude. Here we present results of magnetic and structure studies performed of these compounds, focusing on the correlation between magnetic and structural variations and discussing possible reasons of the striking difference in effect of hydrogenation on rare-earth and actinide intermetallics.

Bordallo, H. N.; Drulis, H.; Havela, L.; Iwasieczko, W.; Kolomiets, A. V.; Nakotte, H.; Refaja, D.; Yartys, V. A.

1999-08-11T23:59:59.000Z

128

Final Report for the DOE Metal Hydride Center of Excellence  

NLE Websites -- All DOE Office Websites (Extended Search)

SANDIA REPORT SANDIA REPORT SAND2012-0786 Unlimited Release Printed February 2012 Final Report for the DOE Metal Hydride Center of Excellence Lennie Klebanoff Director, Metal Hydride Center of Excellence Jay Keller Deputy Director, Metal Hydride Center of Excellence Prepared by Sandia National Laboratories Albuquerque, New Mexico 87185 and Livermore, California 94550 Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. Approved for public release; further dissemination unlimited. Issued by Sandia National Laboratories, operated for the United States Department of Energy

129

Models for Metal Hydride Particle Shape, Packing, and Heat Transfer  

E-Print Network (OSTI)

A multiphysics modeling approach for heat conduction in metal hydride powders is presented, including particle shape distribution, size distribution, granular packing structure, and effective thermal conductivity. A statistical geometric model is presented that replicates features of particle size and shape distributions observed experimentally that result from cyclic hydride decreptitation. The quasi-static dense packing of a sample set of these particles is simulated via energy-based structural optimization methods. These particles jam (i.e., solidify) at a density (solid volume fraction) of 0.665+/-0.015 - higher than prior experimental estimates. Effective thermal conductivity of the jammed system is simulated and found to follow the behavior predicted by granular effective medium theory. Finally, a theory is presented that links the properties of bi-porous cohesive powders to the present systems based on recent experimental observations of jammed packings of fine powder. This theory produces quantitative experimental agreement with metal hydride powders of various compositions.

Kyle C. Smith; Timothy S. Fisher

2012-05-04T23:59:59.000Z

130

High-Spin Cobalt Hydrides for Catalysis  

SciTech Connect

Organometallic chemists have traditionally used catalysts with strong-field ligands that give low-spin complexes. However, complexes with a weak ligand field have weaker bonds and lower barriers to geometric changes, suggesting that they may lead to more rapid catalytic reactions. Developing our understanding of high-spin complexes requires the use of a broader range of spectroscopic techniques, but has the promise of changing the mechanism and/or selectivity of known catalytic reactions. These changes may enable the more efficient utilization of chemical resources. A special advantage of cobalt and iron catalysts is that the metals are more abundant and cheaper than those currently used for major industrial processes that convert unsaturated organic molecules and biofeedstocks into useful chemicals. This project specifically evaluated the potential of high-spin cobalt complexes for small-molecule reactions for bond rearrangement and cleavage reactions relevant to hydrocarbon transformations. We have learned that many of these reactions proceed through crossing to different spin states: for example, high-spin complexes can flip one electron spin to access a lower-energy reaction pathway for beta-hydride elimination. This reaction enables new, selective olefin isomerization catalysis. The high-spin cobalt complexes also cleave the C-O bond of CO2 and the C-F bonds of fluoroarenes. In each case, the detailed mechanism of the reaction has been determined. Importantly, we have discovered that the cobalt catalysts described here give distinctive selectivities that are better than known catalysts. These selectivities come from a synergy between supporting ligand design and electronic control of the spin-state crossing in the reactions.

Holland, Patrick L. [Yale University] [Yale University

2013-08-29T23:59:59.000Z

131

METHOD OF PREPARING SINTERED ZIRCONIUM METAL FROM ITS HYDRIDES  

DOE Patents (OSTI)

The invention relates to the preparation of metal shapes from zirconium hydride by powder metallurgical techniques. The zirconium hydride powder which is to be used for this purpose can be prepared by rendering massive pieces of crystal bar zirconium friable by heat treatment in purified hydrogen. This any then be ground into powder and powder can be handled in the air without danger of it igniting. It may then be compacted in the normal manner by being piaced in a die. The compact is sintered under vacuum conditions preferably at a temperature ranging from 1200 to 1300 deg C and for periods of one to three hours.

Angier, R.P.

1958-02-11T23:59:59.000Z

132

OBSERVATION AND MECHANISM OF HYDRIDE IN ZIRCALOY-4 AND LOCAL HYDRIDE RE-ORIENTATION INDUCED BY HIGH PRESSURE AT HIGH TEMPERATURES  

SciTech Connect

Hydrided Zircaloy-4 samples were produced by a gas charging method to desired amounts of hydrogen. For low hydrogen content samples, the hydrided platelets appear elongated and needle-like, orientated in the circumferential direction. Mechanical testing was carried out by the ring compression method at various temperatures. Samples with higher hydrogen concentration resulted in lower strain before fracture and reduced maximum load. The trend between temperature and ductility was also very clear: increasing temperatures resulted in increased ductility of the hydrided cladding. A single through-wall crack was observed for a hydrided sample having very high hydrogen concentration under ring compression testing. For samples having lower hydrogen concentrations, the fracture surfaces traversed both circumferential and radial directions, and for which voids were observed near the hydrides. Mechanical tests to study hydride reorientation in these samples are under way, and the results will be reported in the near future.

Yan, Yong [ORNL; Blackwell, Andrew S [ORNL; Plummer, Lee K [ORNL; Radhakrishnan, Balasubramaniam [ORNL; Gorti, Sarma B [ORNL; Clarno, Kevin T [ORNL

2013-01-01T23:59:59.000Z

133

Atomic History  

Science Conference Proceedings (OSTI)

... These Data Centers, one on Atomic Energy Levels and one on Atomic Transition ... After a few years Kessler went on to higher management at NIST. ...

2010-10-05T23:59:59.000Z

134

Atomic magnetometer  

SciTech Connect

An atomic magnetometer is disclosed which uses a pump light beam at a D1 or D2 transition of an alkali metal vapor to magnetically polarize the vapor in a heated cell, and a probe light beam at a different D2 or D1 transition to sense the magnetic field via a polarization rotation of the probe light beam. The pump and probe light beams are both directed along substantially the same optical path through an optical waveplate and through the heated cell to an optical filter which blocks the pump light beam while transmitting the probe light beam to one or more photodetectors which generate electrical signals to sense the magnetic field. The optical waveplate functions as a quarter waveplate to circularly polarize the pump light beam, and as a half waveplate to maintain the probe light beam linearly polarized.

Schwindt, Peter (Albuquerque, NM); Johnson, Cort N. (Albuquerque, NM)

2012-07-03T23:59:59.000Z

135

FEASIBILITY OF RECYCLING PLUTONIUM AND MINOR ACTINIDES IN LIGHT WATER REACTORS USING HYDRIDE FUEL  

Science Conference Proceedings (OSTI)

The objective of this DOE NERI program sponsored project was to assess the feasibility of improving the plutonium (Pu) and minor actinide (MA) recycling capabilities of pressurized water reactors (PWRs) by using hydride instead of oxide fuels. There are four general parts to this assessment: 1) Identifying promising hydride fuel assembly designs for recycling Pu and MAs in PWRs 2) Performing a comprehensive systems analysis that compares the fuel cycle characteristics of Pu and MA recycling in PWRs using the promising hydride fuel assembly designs identified in Part 1 versus using oxide fuel assembly designs 3) Conducting a safety analysis to assess the likelihood of licensing hydride fuel assembly designs 4) Assessing the compatibility of hydride fuel with cladding materials and water under typical PWR operating conditions Hydride fuel was found to offer promising transmutation characteristics and is recommended for further examination as a possible preferred option for recycling plutonium in PWRs.

Greenspan, Ehud; Todreas, Neil; Taiwo, Temitope

2009-03-10T23:59:59.000Z

136

Composition and function in AB{sub 5} hydride electrodes  

DOE Green Energy (OSTI)

Multicomponent AB, hydrides are attractive replacements for the cadmium electrode in nickel - cadmium batteries. This paper is concerned with the differential effects of Ni substitution by cobalt, Mn and Al upon electrode corrosion and capacity, using alloys having the generic composition of Al(NiCoMnAl){sub 5} and similar to those used for the preparation of commercial battery electrodes. The corrosion of metal hydride electrodes is determined by two factors, surface passivation due to the presence of surface oxides or hydroxides and crystal lattice expansion - contraction the charge - discharge process. Thus, in addition to determining the effects of Ni substitution we will also address the question of whether an observed change is due to a change lattice expansion or to a change in surface passivation, e.g. the formation a corrosion resistant oxide layer.

Adzic, G.D.; Johnson, J.R.; Mukerjee, S.; McBreen, J.; Reilly, J.J.

1996-12-31T23:59:59.000Z

137

ALUMINUM HYDRIDE: A REVERSIBLE STORAGE MATERIAL FOR HYDROGEN STORAGE  

DOE Green Energy (OSTI)

One of the challenges of implementing the hydrogen economy is finding a suitable solid H{sub 2} storage material. Aluminium (alane, AlH{sub 3}) hydride has been examined as a potential hydrogen storage material because of its high weight capacity, low discharge temperature, and volumetric density. Recycling the dehydride material has however precluded AlH{sub 3} from being implemented due to the large pressures required (>10{sup 5} bar H{sub 2} at 25 C) and the thermodynamic expense of chemical synthesis. A reversible cycle to form alane electrochemically using NaAlH{sub 4} in THF been successfully demonstrated. Alane is isolated as the triethylamine (TEA) adduct and converted to unsolvated alane by heating under vacuum. To complete the cycle, the starting alanate can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride (NaH) This novel reversible cycle opens the door for alane to fuel the hydrogen economy.

Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B; Joshua Gray, J

2009-01-09T23:59:59.000Z

138

Postirradiation examination of pressure tubes 2954 and 3053: Corrosion, hydriding and fluence measurements  

SciTech Connect

Pressure Tubes 2954 and 3053 were removed from N Reactor in March 1987 for postirradiation examinations (PIE) including hydriding, corrosion, fluence and mechanical property measurements. The results of the corrosion, hydriding, and fluence measurements are the subject of this report. These data will be used to evaluate the trends in corrosion and hydriding behavior which are important to the structural integrity of the tubes. The trend evaluations as well as the mechanical property data are or will be reported elsewhere.

Chastain, S.A.; Trimble, D.J.; Boyd, S.M.

1988-08-01T23:59:59.000Z

139

Thermomechanics of hydrogen storage in metallic hydrides: modeling and analysis  

E-Print Network (OSTI)

A thermodynamically consistent mathematical model for hydrogen adsorption in metal hydrides is proposed. Beside hydrogen diffusion, the model accounts for phase transformation accompanied by hysteresis, swelling, temperature and heat transfer, strain, and stress. We prove existence of solutions of the ensuing system of partial differential equations by a carefully-designed, semi-implicit approximation scheme. A generalization for a drift-diffusion of multi-component ionized "gas" is outlined, too.

Tomas Roubicek; Giuseppe Tomassetti

2013-09-12T23:59:59.000Z

140

Measurement and modeling of strain fields in zirconium hydrides precipitated at a stress concentration  

SciTech Connect

Hydrogen adsorption into zirconium, as a result of corrosion in aqueous environments, leads to the precipitation of a secondary brittle hydride phase. These hydrides tend to first form at stress concentrations such as fretting flaws or cracks in engineering components, potentially degrading the structural integrity of the component. One mechanism for component failure is a slow crack growth mechanism known as Delayed Hydride Cracking (DHC), where hydride fracture occurs followed by crack arrest in the ductile zirconium matrix. The current work employs both an experimental and a modeling approach to better characterize the effects and behavior of hydride precipitation at such stress concentrations. Strains around stress concentrations containing hydrides were mapped using High Energy X-ray Diffraction (HEXRD). These studies highlighted important differences in the behavior of the hydride phase and the surrounding zirconium matrix, as well as the strain associated with the precipitation of the hydride. A finite element model was also developed and compared to the X-ray strain mapping results. This model provided greater insight into details that could not be obtained directly from the experimental approaches, as well as providing a framework for future modeling to predict the effects of hydride precipitation under varied conditions.

Allen, Gregory B.; Kerr, Matthew; Daymond, Mark R. (Queens)

2012-10-23T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Thermodynamics of metal hydrides for hydrogen storage applications using first principles calculations .  

E-Print Network (OSTI)

??Metal hydrides are promising candidates for H2 storage, but high stability and poor kinetics are the important challenges which have to be solved for vehicular (more)

Kim, Ki Chul

2010-01-01T23:59:59.000Z

142

Electrochromically switched, gas-reservoir metal hydride devices with  

NLE Websites -- All DOE Office Websites (Extended Search)

Electrochromically switched, gas-reservoir metal hydride devices with Electrochromically switched, gas-reservoir metal hydride devices with application to energy-efficient windows Title Electrochromically switched, gas-reservoir metal hydride devices with application to energy-efficient windows Publication Type Journal Article LBNL Report Number LBNL-1089E Year of Publication 2008 Authors Anders, André, Jonathan L. Slack, and Thomas J. Richardson Journal Thin Solid Films Volume 1 Date Published 08/2003 Call Number LBNL-1089E Abstract Proof-of-principle gas-reservoir MnNiMg electrochromic mirror devices have been investigated. In contrast to conventional electrochromic approaches, hydrogen is stored (at low concentration) in the gas volume between glass panes of the insulated glass units (IGUs). The elimination of a solid state ion storage layer simplifies the layer stack, enhances overall transmission, and reduces cost. The cyclic switching properties were demonstrated and system durability improved with the incorporation a thin Zr barrier layer between the MnNiMg layer and the Pd catalyst. Addition of 9% silver to the palladium catalyst further improved system durability. About 100 full cycles have been demonstrated before devices slow considerably. Degradation of device performance appears to be related to Pd catalyst mobility, rather than delamination or metal layer oxidation issues originally presumed likely to present significant challenges.

143

Characterization of the molecular structure and mechanical properties of polymer surfaces and protein/polymer interfaces by sum frequency generation vibrational spectroscopy and atomic force microscopy  

SciTech Connect

Sum frequency generation (SFG) vibrational spectroscopy, atomic force microscopy (AFM), and other complementary surface-sensitive techniques have been used to study the surface molecular structure and surface mechanical behavior of biologically-relevant polymer systems. SFG and AFM have emerged as powerful analytical tools to deduce structure/property relationships, in situ, for polymers at air, liquid and solid interfaces. The experiments described in this dissertation have been performed to understand how polymer surface properties are linked to polymer bulk composition, substrate hydrophobicity, changes in the ambient environment (e.g., humidity and temperature), or the adsorption of macromolecules. The correlation of spectroscopic and mechanical data by SFG and AFM can become a powerful methodology to study and engineer materials with tailored surface properties. The overarching theme of this research is the interrogation of systems of increasing structural complexity, which allows us to extend conclusions made on simpler model systems. We begin by systematically describing the surface molecular composition and mechanical properties of polymers, copolymers, and blends having simple linear architectures. Subsequent chapters focus on networked hydrogel materials used as soft contact lenses and the adsorption of protein and surfactant at the polymer/liquid interface. The power of SFG is immediately demonstrated in experiments which identify the chemical parameters that influence the molecular composition and ordering of a polymer chain's side groups at the polymer/air and polymer/liquid interfaces. In general, side groups with increasingly greater hydrophobic character will be more surface active in air. Larger side groups impose steric restrictions, thus they will tend to be more randomly ordered than smaller hydrophobic groups. If exposed to a hydrophilic environment, such as water, the polymer chain will attempt to orient more of its hydrophilic groups to the surface in order to minimize the total surface energy. With an understanding of the structural and environmental parameters which govern polymer surface structure, SFG is then used to explore the effects of surface hydrophobicity and solvent polarity on the orientation and ordering of amphiphilic neutral polymers adsorbed at the solid/liquid interface. SFG spectra show that poly(propylene glycol) (PPG) and poly(ethylene glycol) (PEG) adsorb with their hydrophobic moieties preferentially oriented toward hydrophobic polystyrene surfaces. These same moieties, however, disorder when adsorbed onto a hydrophilic silica/water interface. Water is identified as a critical factor for mediating the orientation and ordering of hydrophobic moieties in polymers adsorbed at hydrophobic interfaces. The role of bulk water content and water vapor, as they influence hydrogel surface structure and mechanics, continues to be explored in the next series of experiments. A method was developed to probe the surface viscoelastic properties of hydroxylethyl methacrylate (HEMA) based contact lens materials by analyzing AFM force-distance curves. AFM analysis indicates that the interfacial region is dehydrated, relative to the bulk. Experiments performed on poly(HEMA+MA) (MA = methacrylic acid), a more hydrophilic copolymer with greater bulk water content, show even greater water depletion at the surface. SFG spectra, as well as surface energy arguments, suggest that the more hydrophilic polymer component (such as MA) is not favored at the air interface; this may explain anomalies in water retention at the hydrogel surface. Adsorption of lysozyme onto poly(HEMA+MA) was found to further reduce near-surface viscous behavior, suggesting lower surface water content. Lastly, protein adsorption is studied using a model polymer system of polystyrene covalently bound with a monolayer of bovine serum albumin. SFG results indicate that some amino acid residues in proteins adopt preferred orientations. SFG spectra also show that the phenyl rings of the bare polystyrene substrate in contact with air or

Koffas, Telly Stelianos

2004-05-15T23:59:59.000Z

144

Cluster generator  

DOE Patents (OSTI)

Described herein is an apparatus and a method for producing atom clusters based on a gas discharge within a hollow cathode. The hollow cathode includes one or more walls. The one or more walls define a sputtering chamber within the hollow cathode and include a material to be sputtered. A hollow anode is positioned at an end of the sputtering chamber, and atom clusters are formed when a gas discharge is generated between the hollow anode and the hollow cathode.

Donchev, Todor I. (Urbana, IL); Petrov, Ivan G. (Champaign, IL)

2011-05-31T23:59:59.000Z

145

The affect of erbium hydride on the conversion efficience to accelerated protons from ultra-shsort pulse laser irradiated foils  

DOE Green Energy (OSTI)

This thesis work explores, experimentally, the potential gains in the conversion efficiency from ultra-intense laser light to proton beams using erbium hydride coatings. For years, it has been known that contaminants at the rear surface of an ultra-intense laser irradiated thin foil will be accelerated to multi-MeV. Inertial Confinement Fusion fast ignition using proton beams as the igniter source requires of about 10{sup 16} protons with an average energy of about 3MeV. This is far more than the 10{sup 12} protons available in the contaminant layer. Target designs must include some form of a hydrogen rich coating that can be made thick enough to support the beam requirements of fast ignition. Work with computer simulations of thin foils suggest the atomic mass of the non-hydrogen atoms in the surface layer has a strong affect on the conversion efficiency to protons. For example, the 167amu erbium atoms will take less energy away from the proton beam than a coating using carbon with a mass of 12amu. A pure hydrogen coating would be ideal, but technologically is not feasible at this time. In the experiments performed for my thesis, ErH{sub 3} coatings on 5 {micro}m gold foils are compared with typical contaminants which are approximately equivalent to CH{sub 1.7}. It will be shown that there was a factor of 1.25 {+-} 0.19 improvement in the conversion efficiency for protons above 3MeV using erbium hydride using the Callisto laser. Callisto is a 10J per pulse, 800nm wavelength laser with a pulse duration of 200fs and can be focused to a peak intensity of about 5 x 10{sup 19}W/cm{sup 2}. The total number of protons from either target type was on the order of 10{sup 10}. Furthermore, the same experiment was performed on the Titan laser, which has a 500fs pulse duration, 150J of energy and can be focused to about 3 x 10{sup 20} W/cm{sup 2}. In this experiment 10{sup 12} protons were seen from both erbium hydride and contaminants on 14 {micro} m gold foils. Significant improvements were also observed but possibly because of the depletion of hydrogen in the contaminant layer case.

Offermann, D

2008-09-04T23:59:59.000Z

146

Hydride production in zircaloy-4 as a function of time and temperature  

E-Print Network (OSTI)

The experiments performed for this thesis were designed to define the primary process variables of time, temperature, and atmosphere for an engineering system that will produce metal powder from recycled nuclear fuel cladding. The proposed system will hydride and mill Zircaloy cladding tubes to produce fine hydride powder and then dehydride the powder to produce metal; this thesis is focused on the hydride formation reaction. These experiments were performed by hydriding nuclear grade Zircaloy-4 tubes under flowing argon-5% hydrogen for various times and temperatures. The result of these experiments is a correlation which relates the rate of zirconium hydride formation to the process temperature. This correlation may now be used to design a method to efficiently produce zirconium hydride powder. It was observed that it is much more effective to hydride the Zircaloy-4 tubes at temperatures below the a-B-d eutectoid temperature of 540C. These samples tended to readily disassemble during the hydride formation reaction and were easily ground to powder. Hydrogen pickup was faster above this temperature but the samples were generally tougher and it was difficult to pulverize them into powder.

Parkison, Adam Joseph

2008-05-01T23:59:59.000Z

147

Mathematical Modelling of a Metal Hydride Hydrogen Storage System Brendan David MacDonald  

E-Print Network (OSTI)

Member Abstract In order for metal hydride hydrogen storage systems to compete with existing energyMathematical Modelling of a Metal Hydride Hydrogen Storage System by Brendan David MacDonald B Hydrogen Storage System by Brendan David MacDonald B.A.Sc., University of Waterloo, 2004 Supervisory

Victoria, University of

148

Hydrogen storage material and process using graphite additive with metal-doped complex hydrides  

DOE Patents (OSTI)

A hydrogen storage material having improved hydrogen absorbtion and desorption kinetics is provided by adding graphite to a complex hydride such as a metal-doped alanate, i.e., NaAlH.sub.4. The incorporation of graphite into the complex hydride significantly enhances the rate of hydrogen absorbtion and desorption and lowers the desorption temperature needed to release stored hydrogen.

Zidan, Ragaiy (Aiken, SC); Ritter, James A. (Lexington, SC); Ebner, Armin D. (Lexington, SC); Wang, Jun (Columbia, SC); Holland, Charles E. (Cayce, SC)

2008-06-10T23:59:59.000Z

149

Analytical and numerical models of uranium ignition assisted by hydride formation  

DOE Green Energy (OSTI)

Analytical and numerical models of uranium ignition assisted by the oxidation of uranium hydride are described. The models were developed to demonstrate that ignition of large uranium ingots could not occur as a result of possible hydride formation during storage. The thermodynamics-based analytical model predicted an overall 17 C temperature rise of the ingot due to hydride oxidation upon opening of the storage can in air. The numerical model predicted locally higher temperature increases at the surface; the transient temperature increase quickly dissipated. The numerical model was further used to determine conditions for which hydride oxidation does lead to ignition of uranium metal. Room temperature ignition only occurs for high hydride fractions in the nominally oxide reaction product and high specific surface areas of the uranium metal.

Totemeier, T.C.; Hayes, S.L. [Argonne National Lab., Idaho Falls, ID (United States). Engineering Div.

1996-05-01T23:59:59.000Z

150

HYDRIDES AND METAL-HYDROGEN SYSTEMS. Final Report  

DOE Green Energy (OSTI)

The work reported deals with the preparation and physical properties, especially thermal dissociation pressures, and densities of hydrides, hydrogen- metal systems, and mixtures of hydrides with other substances. Possible applicatlons as moderators, high-temperature neutron shields, and low-temperature shields are cited and design problems discussed. Most of the data on dissociation pressures cover ranges and compounds not hltherto explored because of experimental difficulties and the basic knowledge of the thermal behavior of hydrides was substantially increased. New hydrldes were prepared and several reported in the literature were shown not to exist. The following compounds, mixtures, and systems were studled: Tl-H, U-H, Ll-H, Na-H, Ca-H, Ba-H, Th-H, Sr- H; NaH-NaF, NaH-NaOH, NaH-CaH/, LlH-LiF, CaH/sub 2/-CaF/sub 2/, CaH/sub 2/-CaC/ sub 2/,CaH/sub 2/-Ca/sub 3/N/sub 2/; FeH/sub 3/ (alleged), NiH/sub 2/ (alleged), Ti(BH/sub 4/)/sub 3/, Th(BH/sub 4/)/sub 4/, WH/sub 4/ (attempted), W(BH/sub 4/)/ sub 4/ (attempted), /sub 4/NBH/sub 4/, (CH , and ydrides are ing an N/sub H/ comparable to water yet stable at red heat, compounds giving a neutron shield weight less than half that of water, and compounds suitable for use as hightemperature moderators containing large amounts of hydrogen. (auth)

Gibb, T.R.P. Jr.

1951-04-30T23:59:59.000Z

151

Mathematical modeling of the nickel/metal hydride battery system  

DOE Green Energy (OSTI)

A group of compounds referred to as metal hydrides, when used as electrode materials, is a less toxic alternative to the cadmium hydroxide electrode found in nickel/cadmium secondary battery systems. For this and other reasons, the nickel/metal hydride battery system is becoming a popular rechargeable battery for electric vehicle and consumer electronics applications. A model of this battery system is presented. Specifically the metal hydride material, LaNi{sub 5}H{sub 6}, is chosen for investigation due to the wealth of information available in the literature on this compound. The model results are compared to experiments found in the literature. Fundamental analyses as well as engineering optimizations are performed from the results of the battery model. In order to examine diffusion limitations in the nickel oxide electrode, a ``pseudo 2-D model`` is developed. This model allows for the theoretical examination of the effects of a diffusion coefficient that is a function of the state of charge of the active material. It is found using present data from the literature that diffusion in the solid phase is usually not an important limitation in the nickel oxide electrode. This finding is contrary to the conclusions reached by other authors. Although diffusion in the nickel oxide active material is treated rigorously with the pseudo 2-D model, a general methodology is presented for determining the best constant diffusion coefficient to use in a standard one-dimensional battery model. The diffusion coefficients determined by this method are shown to be able to partially capture the behavior that results from a diffusion coefficient that varies with the state of charge of the active material.

Paxton, B.K. [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering]|[Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

1995-09-01T23:59:59.000Z

152

ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE  

DOE Green Energy (OSTI)

Hydrogen storage is one of the challenges to be overcome for implementing the ever sought hydrogen economy. Here we report a novel cycle to reversibly form high density hydrogen storage materials such as aluminium hydride. Aluminium hydride (AlH{sub 3}, alane) has a hydrogen storage capacity of 10.1 wt% H{sub 2}, 149 kg H{sub 2}/m{sup 3} volumetric density and can be discharged at low temperatures (< 100 C). However, alane has been precluded from use in hydrogen storage systems because of the lack of practical regeneration methods. The direct hydrogenation of aluminium to form AlH{sub 3} requires over 10{sup 5} bars of hydrogen pressure at room temperature and there are no cost effective synthetic means. Here we show an unprecedented reversible cycle to form alane electrochemically, using alkali metal alanates (e.g. NaAlH{sub 4}, LiAlH{sub 4}) in aprotic solvents. To complete the cycle, the starting alanates can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride being the other compound formed in the electrochemical cell. The process of forming NaAlH{sub 4} from NaH and Al is well established in both solid state and solution reactions. The use of adducting Lewis bases is an essential part of this cycle, in the isolation of alane from the mixtures of the electrochemical cell. Alane is isolated as the triethylamine (TEA) adduct and converted to pure, unsolvated alane by heating under vacuum.

Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B; Joshua Gray, J

2009-01-09T23:59:59.000Z

153

ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE  

DOE Green Energy (OSTI)

Hydrogen storage is one of the greatest challenges for implementing the ever sought hydrogen economy. Here we report a novel cycle to reversibly form high density hydrogen storage materials such as aluminium hydride. Aluminium hydride (AlH{sub 3}, alane) has a hydrogen storage capacity of 10.1 wt% H{sub 2}, 149 kg H{sub 2}/m{sup 3} volumetric density and can be discharged at low temperatures (< 100 C). However, alane has been precluded from use in hydrogen storage systems because of the lack of practical regeneration methods; the direct hydrogenation of aluminium to form AlH{sub 3} requires over 10{sup 5} bars of hydrogen pressure at room temperature and there are no cost effective synthetic means. Here we show an unprecedented reversible cycle to form alane electrochemically, using alkali alanates (e.g. NaAlH{sub 4}, LiAlH{sub 4}) in aprotic solvents. To complete the cycle, the starting alanates can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride being the other compound formed in the electrochemical cell. The process of forming NaAlH{sub 4} from NaH and Al is well established in both solid state and solution reactions. The use of adducting Lewis bases is an essential part of this cycle, in the isolation of alane from the mixtures of the electrochemical cell. Alane is isolated as the triethylamine (TEA) adduct and converted to pure, unsolvated alane by heating under vacuum.

Fewox, C; Ragaiy Zidan, R; Brenda Garcia-Diaz, B

2008-12-31T23:59:59.000Z

154

Designation of Sites for Remedial Action - Metal Hydrides, Beverly,  

Office of Legacy Management (LM)

T: T: Designation of Sites for Remedial Action - Metal Hydrides, Beverly, MA; Bridgeport Brass, Adrian, MI and Seymour, Chicago, IL CT; National Guard Armory, 0: Joe LaGrone, Manager Oak Ridge Operations Office Based on the attached radiological survey data (Attachments 1 through 3) and an appropriate authority review, the following properties are being authorized for remedial action. It should be noted that the attached survey data are for designation purposes only and that Bechtel National, Inc. (BNI) should conduct appropriate comprehensive characterization studies to determine the extent'and magnitude of contamination on properties. Site Location Priority Former Bridgeport Brass Co. (General Motors) Adrian, MI Low Former Bridgeport Brass Co.

155

Sintering of sponge and hydride-dehydride titanium powders  

Science Conference Proceedings (OSTI)

The sintering behavior of compacts produced from sponge and hydride-dehydride (HDH) Ti powders was examined. Compacts were vacuum sintered at 1200 or 1300 deg C for 30, 60, 120, 240, 480 or 960 minutes. The porosity decreased with sintering time and/or temperature in compacts produced from the HDH powders. Compacts produced from these powders could be sintered to essentially full density. However, the sintering condition did not influence the amount of porosity present in compacts produced from the sponge powders. These samples could only be sintered to a density of 97% theoretical. The sintering behavior was attributed to the chemical impurities in the powders.

Alman, David E.; Gerdemann, Stephen J.

2004-04-01T23:59:59.000Z

156

Metal hydride based isotope separation: Large-scale operations  

DOE Green Energy (OSTI)

A program to develop a metal hydride based hydrogen isotope separation process began at the Savannah River Laboratory in 1980. This semi-continuous gas chromatographic separation process will be used in new tritium facilities at the Savannah River Site. A tritium production unit is scheduled to start operation in 1993. An experimental, large-scale unit is currently being tested using protium and deuterium. Operation of the large-scale unit has demonstrated separation of mixed hydrogen isotopes (55% protium and 45% deuterium), resulting in protium and deuterium product streams with purities better than 99.5%. 3 refs., 4 figs.

Horen, A.S.; Lee, Myung W.

1991-01-01T23:59:59.000Z

157

Metal hydride based isotope separation: Large-scale operations  

DOE Green Energy (OSTI)

A program to develop a metal hydride based hydrogen isotope separation process began at the Savannah River Laboratory in 1980. This semi-continuous gas chromatographic separation process will be used in new tritium facilities at the Savannah River Site. A tritium production unit is scheduled to start operation in 1993. An experimental, large-scale unit is currently being tested using protium and deuterium. Operation of the large-scale unit has demonstrated separation of mixed hydrogen isotopes (55% protium and 45% deuterium), resulting in protium and deuterium product streams with purities better than 99.5%. 3 refs., 4 figs.

Horen, A.S.; Lee, Myung W.

1991-12-31T23:59:59.000Z

158

Chemical Hydrides for Hydrogen Storage in Fuel Cell Applications  

Science Conference Proceedings (OSTI)

Due to its high hydrogen storage capacity (up to 19.6% by weight for the release of 2.5 molar equivalents of hydrogen gas) and its stability under typical ambient conditions, ammonia borane (AB) is a promising material for chemical hydrogen storage for fuel cell applications in transportation sector. Several systems models for chemical hydride materials such as solid AB, liquid AB and alane were developed and evaluated at PNNL to determine an optimal configuration that would meet the 2010 and future DOE targets for hydrogen storage. This paper presents an overview of those systems models and discusses the simulation results for various transient drive cycle scenarios.

Devarakonda, Maruthi N.; Brooks, Kriston P.; Ronnebro, Ewa; Rassat, Scot D.; Holladay, Jamelyn D.

2012-04-16T23:59:59.000Z

159

Electronic band structure and optical properties of the cubic, Sc, Y and La hydride systems  

DOE Green Energy (OSTI)

Electronic band structure calculations are used to interpret the optical spectra of the cubic Sc, Y and La hydride systems. Self-consistent band calculations of ScH/sub 2/ and YH/sub 2/ were carried out. The respective joint densities of states are computed and compared to the dielectric functions determined from the optical measurements. Additional calculations were performed in which the Fermi level or band gap energies are rigidly shifted by a small energy increment. These calculations are then used to simulate the derivative structure in thermomodulation spectra and relate the origin of experimental interband features to the calculated energy bands. While good systematic agreement is obtained for several spectral features, the origin of low-energy interband transitions in YH/sub 2/ cannot be explained by these calculated bands. A lattice-size-dependent premature occupation of octahedral sites by hydrogen atoms in the fcc metal lattice is suggested to account for this discrepancy. Various non-self-consistent calculations are used to examine the effect of such a premature occupation. Measurements of the optical absorptivity of LaH/sub x/ with 1.6 < x < 2.9 are presented which, as expected, indicate a more premature occupation of the octahedral sites in the larger LaH/sub 2/ lattice. These experimental results also suggest that, in contrast to recent calculations, LaH/sub 3/ is a small-band-gap semiconductor.

Peterman, D.J.

1980-01-01T23:59:59.000Z

160

ACCEPTABILITY ENVELOPE FOR METAL HYDRIDE-BASED HYDROGEN STORAGE SYSTEMS  

DOE Green Energy (OSTI)

The design and evaluation of media based hydrogen storage systems requires the use of detailed numerical models and experimental studies, with significant amount of time and monetary investment. Thus a scoping tool, referred to as the Acceptability Envelope, was developed to screen preliminary candidate media and storage vessel designs, identifying the range of chemical, physical and geometrical parameters for the coupled media and storage vessel system that allow it to meet performance targets. The model which underpins the analysis allows simplifying the storage system, thus resulting in one input-one output scheme, by grouping of selected quantities. Two cases have been analyzed and results are presented here. In the first application the DOE technical targets (Year 2010, Year 2015 and Ultimate) are used to determine the range of parameters required for the metal hydride media and storage vessel. In the second case the most promising metal hydrides available are compared, highlighting the potential of storage systems, utilizing them, to achieve 40% of the 2010 DOE technical target. Results show that systems based on Li-Mg media have the best potential to attain these performance targets.

Hardy, B.; Corgnale, C.; Tamburello, D.; Garrison, S.; Anton, D.

2011-07-18T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

A deformation and thermodynamic model for hydride precipitation kinetics in spent fuel cladding  

DOE Green Energy (OSTI)

Hydrogen is contained in the Zircaloy cladding of spent fuel rods from nuclear reactors. All the spent fuel rods placed in a nuclear waste repository will have a temperature history that decreases toward ambient; and as a result, most all of the hydrogen in the Zircaloy will eventually precipitate as zirconium hydride platelets. A model for the density of hydride platelets is a necessary sub-part for predicting Zircaloy cladding failure rate in a nuclear waste repository. A model is developed to describe statistically the hydride platelet density, and the density function includes the orientation as a physical attribute. The model applies concepts from statistical mechanics to derive probable deformation and thermodynamic functionals for cladding material response that depend explicitly on the hydride platelet density function. From this model, hydride precipitation kinetics depend on a thermodynamic potential for hydride density change and on the inner product of a stress tensor and a tensor measure for the incremental volume change due to hydride platelets. The development of a failure response model for Zircaloy cladding exposed to the expected conditions in a nuclear waste repository is supported by the US DOE Yucca Mountain Project. 19 refs., 3 figs.

Stout, R.B.

1989-10-01T23:59:59.000Z

162

Determination of white phosphorus residues in ducks: An atomic emission detection/compound-independent calibration-based method of generating residue data for risk assessment and environmental monitoring  

Science Conference Proceedings (OSTI)

Analysis of phosphorus concentrations in the gizzards of ducks harvested from munitions sites is necessary to ascertain if acute phosphorus toxicity was the cause of death and to estimate potential secondary hazards to predators and scavengers, such as eagles that readily consume the dead ducks. Gas chromatography-atomic emission detection analysis permitted compound-independent quantification of white phosphorus standards following analysis of the stable phosphorus-containing compound triethyl phosphate. The white phosphorus standards were then used to quantify white phosphorus residues in duck gizzard extracts by gas chromatography-flame photometric detection analysis. For gizzards containing less than 0.01 {micro}g of phosphorus, quantification was based on a three-point calibration curve. For gizzards containing 0.01 {micro}g or more of white phosphorus, single-point calibration was used. Mean recoveries for phosphorus-fortified gizzards ranged from 73 to 91%. The method limit of detection was 0.013 {micro}g of phosphorus. This method was successfully applied to the quantification of white phosphorus in ducks collected from Eagle River Flats, AK. Potential applications to risk assessment and environmental monitoring are also discussed.

Johnston, J.J.; Goldade, D.A.; Kohler, D.J.; Cummings, J.L.

2000-05-01T23:59:59.000Z

163

THE PREPARATION OF PLUTONIUM POWDER BY A HYDRIDING PROCESS-INITIAL STUDIES  

DOE Green Energy (OSTI)

Micron-sized plutonium powder was produced by hydriding massive metal, then grinding and decomposing the hydride. An apparatus containing clean plutonium metal was evacuated to a pressure of 10 mu . Dry oxygen-free hydrogen was introduced and the apparatus placed in a furnace. After the reaction started, the apparatus was removed from the furnace and hydrogen added until the reaction was complete. The hydride was decomposed by heating to 400 deg C. Plutonium metal produced in this manner was porous. (C.J.G.)

Stiffler, G.L.; Curtis, M.H.

1960-03-10T23:59:59.000Z

164

DEVELOPMENT OF A FABRICATION PROCESS FOR SOL-GEL/METAL HYDRIDE COMPOSITE GRANULES  

DOE Green Energy (OSTI)

An external gelation process was developed to produce spherical granules that contain metal hydride particles in a sol-gel matrix. Dimensionally stable granules containing metal hydrides are needed for applications such as hydrogen separation and hydrogen purification that require columns containing metal hydrides. Gases must readily flow through the metal hydride beds in the columns. Metal hydrides reversibly absorb and desorb hydrogen and hydrogen isotopes. This is accompanied by significant volume changes that cause the metal hydride to break apart or decrepitate. Repeated cycling results in very fine metal hydride particles that are difficult to handle and contain. Fine particles tend to settle and pack making it more difficult to flow gases through a metal hydride bed. Furthermore, the metal hydrides can exert a significant force on the containment vessel as they expand. These problems associated with metal hydrides can be eliminated with the granulation process described in this report. Small agglomerates of metal hydride particles and abietic acid (a pore former) were produced and dispersed in a colloidal silica/water suspension to form the feed slurry. Fumed silica was added to increase the viscosity of the feed slurry which helped to keep the agglomerates in suspension. Drops of the feed slurry were injected into a 27-foot tall column of hot ({approx}70 C), medium viscosity ({approx}3000 centistokes) silicone oil. Water was slowly evaporated from the drops as they settled. The drops gelled and eventually solidified to form spherical granules. This process is referred to as external gelation. Testing was completed to optimize the design of the column, the feed system, the feed slurry composition, and the operating parameters of the column. The critical process parameters can be controlled resulting in a reproducible fabrication technique. The residual silicone oil on the surface of the granules was removed by washing in mineral spirits. The granules were dried in air at 40 C. The granules were heated to 230 C for 30 minutes in argon to remove the remaining water and organic materials. The resulting product was spherical composite granules (100 to 2000 micron diameter) with a porous silica matrix containing small agglomerates of metal hydride particles. Open porosity in the silica matrix allows hydrogen to permeate rapidly through the matrix but the pores are small enough to contain the metal hydride particles. Additional porosity around the metal hydride particles, induced using abietic acid as a pore former, allows the particles to freely expand and contract without fracturing the brittle sol-gel matrix. It was demonstrated that the granules readily absorb and desorb hydrogen while remaining integral and dimensionally stable. Microcracking was observed after the granules were cycled in hydrogen five times. The strength of the granules was improved by coating them with a thin layer of a micro-porous polymer sol-gel that would allow hydrogen to freely pass through the coating but would filter out metal hydride poisons such as water and carbon monoxide. It was demonstrated that if a thin sol-gel coating was applied after the granules were cycled, the coating not only improved the strength of the granules but the coated granules retained their strength after additional hydrogen cycling tests. This additional strength is needed to extend the lifetime of the granules and to survive the compressive load in a large column of granules. Additional hydrogen adsorption tests are planned to evaluate the performance of coated granules after one hundred cycles. Tests will also be performed to determine the effects of metal hydride poisons on the granules. The results of these tests will be documented in a separate report. The process that was developed to form these granules could be scaled to a production process. The process to form granules from a mixture of metal hydride particles and pore former such as abietic acid can be scaled up using commercial granulators. The current laboratory-scale external gelation column produc

Hansen, E; Eric Frickey, E; Leung Heung, L

2004-02-23T23:59:59.000Z

165

Final report for the DOE Metal Hydride Center of Excellence.  

DOE Green Energy (OSTI)

This report summarizes the R&D activities within the U.S. Department of Energy Metal Hydride Center of Excellence (MHCoE) from March 2005 to June 2010. The purpose of the MHCoE has been to conduct highly collaborative and multi-disciplinary applied R&D to develop new reversible hydrogen storage materials that meet or exceed DOE 2010 and 2015 system goals for hydrogen storage materials. The MHCoE combines three broad areas: mechanisms and modeling (which provide a theoretically driven basis for pursuing new materials), materials development (in which new materials are synthesized and characterized) and system design and engineering (which allow these new materials to be realized as practical automotive hydrogen storage systems). This Final Report summarizes the organization and execution of the 5-year research program to develop practical hydrogen storage materials for light duty vehicles. Major results from the MHCoE are summarized, along with suggestions for future research areas.

Keller, Jay O.; Klebanoff, Leonard E.

2012-01-01T23:59:59.000Z

166

Wall pressure exerted by hydrogenation of sodium aluminum hydride.  

DOE Green Energy (OSTI)

Wall pressure exerted by the bulk expansion of a sodium aluminum hydride bed was measured as a function of hydrogen content. A custom apparatus was designed and loaded with sodium alanates at densities of 1.0, 1.1, and 1.16 g/cc. Four complete cycles were performed to identify variations in measured pressure. Results indicated poor correlation between exerted pressure and hydrogen capacity of the sodium alanate beds. Mechanical pressure due to the hydrogenation of sodium alanates does not influence full-scale system designs as it falls within common design factors of safety. Gas pressure gradients within the porous solid were identified and may limit reaction rates, especially for high aspect ratio beds.

Perras, Yon E.; Dedrick, Daniel E.; Zimmerman, Mark D.

2009-06-01T23:59:59.000Z

167

Nickel-metal hydride battery development. Final technical report  

SciTech Connect

Rechargeable batteries are used as the power source for a broad range of portable equipment. Key battery selection criteria typically are weight, volume, first cost, life cycle cost, and environmental impact. Rechargeable batteries are favored from a life cycle cost and environmental impact standpoint over primary batteries. The nickel-metal hydride (Ni-MH) battery system has emerged as the battery of choice for many applications based on its superior characteristics when judged on the above criteria against other battery types. In most cases commercial Ni-MH batteries are constructed with coiled electrodes in cylindrical metal containers. Electro Energy, Inc. (EEI) has been developing a novel flat bipolar configuration of the Ni-MH system that offers weight, volume, and cost advantages when compared to cylindrical cells. The unique bipolar approach consists of fabricating individual flat wafer cells in conductive, carbon-filled, plastic face plates. The individual cells contain a nonconductive plastic border which is heat sealed around the perimeter to make a totally sealed unit cell. Multi-cell batteries are fabricated by stacking the individual wafer cells in such a way that the positive face of one cell contacts the negative face of the adjacent cell. The stack is then contained in an outer housing with end contacts. The purpose of this program was to develop, evaluate, and demonstrate the capabilities of the EEI Ni-MH battery system for consumer applications. The work was directed at the development and evaluation of the compact bipolar construction for its potential advantages of high power and energy density. Experimental investigations were performed on various nickel electrode types, hydride electrode formulations, and alternate separator materials. Studies were also directed at evaluating various oxygen recombination techniques for low pressure operation during charge and overcharge.

1995-06-01T23:59:59.000Z

168

Model for Simulation of Hydride Precipitation in Zr-Based Used Fuel  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

for Simulation of Hydride Precipitation in Zr-Based Used Fuel for Simulation of Hydride Precipitation in Zr-Based Used Fuel Claddings: A Status Report on Current Model Capabilities Model for Simulation of Hydride Precipitation in Zr-Based Used Fuel Claddings: A Status Report on Current Model Capabilities The report demonstrates a meso-scale, microstructural evolution model for simulation of zirconium hydride precipitation in the cladding of used fuels during long-term dry-storage. While the Zr-based claddings (regarded as a barrier for containment of radioactive fission products and fuel) are manufactured free of any hydrogen, they absorb hydrogen during service in the reactor. The amount of hydrogen that the cladding picks up is primarily a function of the exact chemistry and microstructure of the claddings and reactor operating conditions, time-temperature history, and

169

Some new techniques in tritium gas handling as applied to metal hydride synthesis  

SciTech Connect

A state-of-the-art tritium Hydride Synthesis System (HSS) was designed and built to replace the existing system within the Tritium Salt Facility (TSF) at the Los Alamos National Laboratory. This new hydriding system utilized unique fast-cycling 5.63 mole uranium beds (50.9 g to T/sub 2/ at 100% loading) and novel gas circulating hydriding furnaces. Tritium system components discussed include fast-cycling uranium beds, circulating gas hydriding furnaces, valves, storage volumes, manifolds, gas transfer pumps, and graphic display and control consoles. Many of the tritium handling and processing techniques incorporated into this system are directly applicable to today's fusion fuel loops.

Nasise, J.E.

1988-09-01T23:59:59.000Z

170

Some new techniques in tritium gas handling as applied to metal hydride synthesis  

SciTech Connect

A state-of-the-art tritium Hydriding Synthesis System (HSS) was designed and built to replace the existing system within the Tritium Salt Facility (TSF) at the Los Alamos National Laboratory. This new hydriding system utilizes unique fast-cycling 7.9 mole uranium beds (47.5g of T at 100% loading) and novel gas circulating hydriding furnaces. Tritium system components discussed include fast-cycling uranium beds, circulating gas hydriding furnaces, valves, storage volumes, manifolds, gas transfer pumps, and graphic display and control consoles. Many of the tritium handling and processing techniques incorporated into this system are directly applicable to today's fusion fuel loops. 12 refs., 7 figs.

Nasise, J.E.

1988-01-01T23:59:59.000Z

171

Development of lightweight hydrides. Annual task report, August 1978-September 1978  

DOE Green Energy (OSTI)

The results of the first years effort to develop lightweight hydrides for automotive storage of hydrogen are described. A test fixture to subject a magnesium alloy hydride to hundreds of hydriding cycles has been designed and is being constructed. Extensive testing of the magnesium lithium and magnesium aluminum alloy hydrides has been performed. Several alloys demonstrate significantly higher hydrogen dissociation pressures than the baseline alloy Mg/sub 2/Ni-Mg. No alloy has yet demonstrated one atmosphere of hydrogen pressure at the goal temperature of 200/sup 0/C. Hydrogen capacity varies greatly with alloy composition. Alloys with high dissociation pressures have hydrogen capacities up to 3.6% by weight. Plans include the reduction of aluminum content in the alloys to increase the hydrogen capacity.

Rohy, D.A.; Nachman, J.F.

1979-10-01T23:59:59.000Z

172

Photogeneration of Hydride Donors and Their Use Toward CO2 Reduction  

DOE Green Energy (OSTI)

Despite substantial effort, no one has succeeded in efficiently producing methanol from CO2 using homogeneous photocatalytic systems. We are pursuing reaction schemes based on a sequence of hydride-ion transfers to carry out stepwise reduction of CO2 to methanol. We are using hydride-ion transfer from photoproduced C-H bonds in metal complexes with bio-inspired ligands (i.e., NADH-like ligands) that are known to store one proton and two electrons.

Fujita,E.; Muckerman, J.T.; Polyansky, D.E.

2009-06-07T23:59:59.000Z

173

Atomic line emission analyzer for hydrogen isotopes  

DOE Patents (OSTI)

Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

1993-01-01T23:59:59.000Z

174

Atomic line emission analyzer for hydrogen isotopes  

DOE Patents (OSTI)

Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using, a metal hydride.

Kronberg, J.W.

1991-05-08T23:59:59.000Z

175

Atomic line emission analyzer for hydrogen isotopes  

DOE Patents (OSTI)

Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

Kronberg, J.W.

1993-03-30T23:59:59.000Z

176

CHARACTERIZATION OF THE LOCAL TITANIUM ENVIRONMENT IN DOPED SODIUM ALUMINUM HYDRIDE USING X-RAY ADSORPTION SPECTROSCOPY.  

DOE Green Energy (OSTI)

Ti K-edge x-ray absorption spectroscopy was used to explore the local titanium environment and valence in 2-4 mol% Ti-doped sodium alanate. An estimate of the oxidation state of the dopant, based upon known standards, revealed a zero-valent titanium atom. An analysis of the near-edge and extended fine structures indicates that the Ti does not enter substitutional or interstitial sites in the NaAlH{sub 4} lattice. Rather, the Ti is located on/near the surface and is coordinated by 10.2 {+-} 1 aluminum atoms with an interatomic distance of 2.82 {+-} 0.01 {angstrom}, similar to that of TiAl{sub 3}. The Fourier transformed EXAFS spectra reveals a lack of long-range order around the Ti dopant indicating that the Ti forms nano-clusters of TiAl{sub 3}. The similarity of the spectra in the hydrided and dehydrided samples suggests that the local Ti environment is nearly invariant during hydrogen cycling.

GRAETZ, J.; IGNATOV, A. YU; TYSON, T.A.; REILLY, J.J.; JOHNSON, J.

2004-11-30T23:59:59.000Z

177

Test of the quantumness of atom-atom correlations in a bosonic gas  

E-Print Network (OSTI)

It is shown how the quantumness of atom-atom correlations in a trapped bosonic gas can be made observable. Application of continuous feedback control of the center of mass of the atomic cloud is shown to generate oscillations of the spatial extension of the cloud, whose amplitude can be directly used as a characterization of atom-atom correlations. Feedback parameters can be chosen such that the violation of a Schwarz inequality for atom-atom correlations can be tested at noise levels much higher than the standard quantum limit.

D. Ivanov; S. Wallentowitz

2006-03-16T23:59:59.000Z

178

Complex Hydride Compounds with Enhanced Hydrogen Storage Capacity  

DOE Green Energy (OSTI)

The United Technologies Research Center (UTRC), in collaboration with major partners Albemarle Corporation (Albemarle) and the Savannah River National Laboratory (SRNL), conducted research to discover new hydride materials for the storage of hydrogen having on-board reversibility and a target gravimetric capacity of ? 7.5 weight percent (wt %). When integrated into a system with a reasonable efficiency of 60% (mass of hydride / total mass), this target material would produce a system gravimetric capacity of ? 4.5 wt %, consistent with the DOE 2007 target. The approach established for the project combined first principles modeling (FPM - UTRC) with multiple synthesis methods: Solid State Processing (SSP - UTRC), Solution Based Processing (SBP - Albemarle) and Molten State Processing (MSP - SRNL). In the search for novel compounds, each of these methods has advantages and disadvantages; by combining them, the potential for success was increased. During the project, UTRC refined its FPM framework which includes ground state (0 Kelvin) structural determinations, elevated temperature thermodynamic predictions and thermodynamic / phase diagram calculations. This modeling was used both to precede synthesis in a virtual search for new compounds and after initial synthesis to examine reaction details and options for modifications including co-reactant additions. The SSP synthesis method involved high energy ball milling which was simple, efficient for small batches and has proven effective for other storage material compositions. The SBP method produced very homogeneous chemical reactions, some of which cannot be performed via solid state routes, and would be the preferred approach for large scale production. The MSP technique is similar to the SSP method, but involves higher temperature and hydrogen pressure conditions to achieve greater species mobility. During the initial phases of the project, the focus was on higher order alanate complexes in the phase space between alkaline metal hydrides (AmH), Alkaline earth metal hydrides (AeH2), alane (AlH3), transition metal (Tm) hydrides (TmHz, where z=1-3) and molecular hydrogen (H2). The effort started first with variations of known alanates and subsequently extended the search to unknown compounds. In this stage, the FPM techniques were developed and validated on known alanate materials such as NaAlH4 and Na2LiAlH6. The coupled predictive methodologies were used to survey over 200 proposed phases in six quaternary spaces, formed from various combinations of Na, Li Mg and/or Ti with Al and H. A wide range of alanate compounds was examined using SSP having additions of Ti, Cr, Co, Ni and Fe. A number of compositions and reaction paths were identified having H weight fractions up to 5.6 wt %, but none meeting the 7.5 wt%H reversible goal. Similarly, MSP of alanates produced a number of interesting compounds and general conclusions regarding reaction behavior of mixtures during processing, but no alanate based candidates meeting the 7.5 wt% goal. A novel alanate, LiMg(AlH4)3, was synthesized using SBP that demonstrated a 7.0 wt% capacity with a desorption temperature of 150C. The deuteride form was synthesized and characterized by the Institute for Energy (IFE) in Norway to determine its crystalline structure for related FPM studies. However, the reaction exhibited exothermicity and therefore was not reversible under acceptable hydrogen gas pressures for on-board recharging. After the extensive studies of alanates, the material class of emphasis was shifted to borohydrides. Through SBP, several ligand-stabilized Mg(BH4)2 complexes were synthesized. The Mg(BH4)2*2NH3 complex was found to change behavior with slightly different synthesis conditions and/or aging. One of the two mechanisms was an amine-borane (NH3BH3) like dissociation reaction which released up to 16 wt %H and more conservatively 9 wt%H when not including H2 released from the NH3. From FPM, the stability of the Mg(BH4)2*2NH3 compound was found to increase with the inclusion of NH3 groups in the inner-Mg coordination

Mosher, Daniel A.; Opalka, Susanne M.; Tang, Xia; Laube, Bruce L.; Brown, Ronald J.; Vanderspurt, Thomas H.; Arsenault, Sarah; Wu, Robert; Strickler, Jamie; Anton, Donald L.; Zidan, Ragaiy; Berseth, Polly

2008-02-18T23:59:59.000Z

179

Postirradiation examination of Pressure Tubes 2755 and 1054 Part 1: Dimensional, hydride, inner surface defects, and corrosion measurements: Addendum 1  

Science Conference Proceedings (OSTI)

This addendum is issued to document additional postirradiation examinations that were conducted on Pressure Tubes 2755 and 1054 for evaluation of inner surface defects, corrosion and hydride measurements.

Chastain, S.A.; Trimble, D.J.

1986-04-01T23:59:59.000Z

180

Synthesis and characterization of metal hydride electrodes. Interim report  

DOE Green Energy (OSTI)

The objective of this project is to elucidate the compositional and structural parameters that affect the thermodynamics, kinetics and stability of alloy hydride electrodes and to use this information in the development of new high capacity long life hydride electrodes for rechargeable batteries. The work focuses on the development of AB{sub 5} alloys and the application of in situ methods, at NSLS, such as x-ray absorption (XAS), to elucidate the role of the alloying elements in hydrogen storage and corrosion inhibition. The most significant results to date are: The decay of electrode capacity on cycling was directly related to alloy corrosion. The rate of corrosion depended in part on both the alloy composition and the partial molar volume of hydrogen, V{sub H}. The corrosion rate depended on the composition of the A component in AB{sub 5} (LaNi{sub 5} type) alloys. Partial substitution of La with Ce in AB{sub 5} alloys substantially inhibits electrode corrosion on cycling. Recent results indicate that Co also greatly inhibits electrode corrosion, possibly by minimizing V{sub H}. The AB{sub 5} alloys investigated included LaNi{sub 5}, ternary alloys (e.g. LaN{sub 4.8}Sn{sub 0.2} and La{sub 0.8}Ce{sub 0.2}Ni{sub 5}), alloys with various substitutions for both La and Ni (e.g. La{sub 0.8}Ce{sub 0.2}Ni{sub 4.8}Sn{sub 0.2}) and mischmetal (Mm) alloys of the type normally used in batteries, such as MmB{sub 5} (B = Ni{sub 3.55}Mn{sub 0.4}A1{sub 0.3}Co{sub 0.75}). A major effort was devoted to the effects of La substitution in the A component. Both in situ and ex situ XAS measurements are used to study the electronic effects that occur on the addition of various metal substitutions and on the ingress of hydrogen.

McBreen, J.; Reilly, J.J.

1995-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Glossary Term - Atomic Number  

NLE Websites -- All DOE Office Websites (Extended Search)

Particle Previous Term (Alpha Particle) Glossary Main Index Next Term (Avogadro's Number) Avogadro's Number Atomic Number Silver's atomic number is 47 The atomic number is equal to...

182

Monitoring atom-atom entanglement and decoherence in a solvable tripartite open system in cavity QED  

E-Print Network (OSTI)

We solve exactly the dynamics of two strongly-driven two-level atoms resonantly coupled to a dissipative cavity field mode. Starting with the cavity field vacuum state, we show that the entanglement of the atom-atom subsystem cannot be created or increased. On the other hand, when the atoms are initially entangled the atomic Hilbert space divides into two subspaces. One of them is decoherence free so that the initial atomic entanglement remains available for applications, even in presence of a low enough atomic decay rate. In the other subspace a measure of entanglement, decoherence, and also purity, are described by a similar functional behavior that can be monitored by joint atomic measurements. Furthermore, we show the possible generation of Schr\\"odinger-cat-like states for the whole system in the transient regime, as well as of entanglement for the cavity field and the atom-atom subsystems conditioned by measurements on the complementary subsystem.

Bina, Matteo; Lulli, Alfredo; Solano, Enrique

2007-01-01T23:59:59.000Z

183

Alternatives for metal hydride storage bed heating and cooling  

DOE Green Energy (OSTI)

The reaction of hydrogen isotopes with the storage bed hydride material is exothermic during absorption and endothermic during desorption. Therefore, storage bed operation requires a cooling system to remove heat during absorption, and a heating system to add the heat needed for desorption. Three storage bed designs and their associated methods of heating and cooling and accountability are presented within. The first design is the current RTF (Replacement Tritium Facility) nitrogen heating and cooling system. The second design uses natural convection cooling with ambient glove box nitrogen and electrical resistance for heating. This design is referred to as the Naturally Cooled/Electrically Heated (NCEH) design. The third design uses forced convection cooling with ambient glove box nitrogen and electrical resistance for heating. The design is referred to as the Forced Convection Cooled/Electrically Heated (FCCEH) design. In this report the operation, storage bed design, and equipment required for heating, cooling, and accountability of each design are described. The advantages and disadvantages of each design are listed and discussed. Based on the information presented within, it is recommended that the NCEH design be selected for further development.

Fisher, I.A.; Ramirez, F.B.; Koonce, J.E.; Ward, D.E.; Heung, L.K.; Weimer, M.; Berkebile, W.; French, S.T.

1991-10-04T23:59:59.000Z

184

Golden Sections of Interatomic Distances as Exact Ionic Radii and Additivity of Atomic and Ionic Radii in Chemical Bonds  

E-Print Network (OSTI)

The Golden ratio which appears in the geometry of a variety of creations in Nature is found to arise right in the Bohr radius of the hydrogen atom due to the opposite charges of the electron and proton. The bond length of the hydrogen molecule is the diagonal of a square on the Bohr radius and hence also has two Golden sections, which form the cationic and anionic radii of hydrogen. It is shown here that these radii account for the bond lengths of many hydrides when added to the atomic and Golden ratio based ionic radii of many other atoms.

Raji Heyrovska

2009-02-06T23:59:59.000Z

185

HYCSOS: a chemical heat pump and energy conversion system based on metal hydrides. 1979 status report  

DOE Green Energy (OSTI)

The current status of the HYCSOS chemical heat pump and energy conversion system based on metal hydrides is described. Heat transfer fluid loops were insulated and modified for isothermal operation. Software development for HYCSOS manual mode operation was completed. Routines to handle data acquisition, logging, compression, correction and plotting, using a Tektronix Graphics system with flexible disk data storage, provide a rapid and versatile means of presenting HYCSOS data for analysis. Advanced concept heat exchangers to improve the heat transfer of the hydride bed with the heat transfer fluid are discussed. Preliminary tests made with a LaNi/sub 5/ loaded aluminum foam test unit showed that heat transfer properties are very markedly improved. Thermodynamic expressions are applied to the selection of alloys for use in HYCSOS. The substitution of aluminum for nickel in AB/sub 5/ type alloys is shown to reduce hysteresis and permits the use of potentially lower cost materials with added flexibility for the optimization of engineering design and performance characteristics of the hydride heat pump system. Transient thermal measurements on hydride beds of CaNi/sub 5/ and LaNi/sub 5/ show no deterioration with cycling. Relatively slow heat transfer between the hydride beds and heat transfer fluid in the coiled tube heat exchangers is indicated by temperature lag of the bed and heat transfer fluid. Improved heat transfer is anticipated with aluminum foam heat exchangers.

Sheft, I.; Gruen, D.M.; Lamich, G.

1979-04-01T23:59:59.000Z

186

Materials Down-selection Decisions Made within the DOE Metal Hydride Center of Excellence (MHCoE) - September-October 2007  

Fuel Cell Technologies Publication and Product Library (EERE)

Reports on which hydrogen storage materials offer potential for further research as decided by DOE's Metal Hydride Center of Excellence.

187

Atomic Spectroscopy Data Center  

Science Conference Proceedings (OSTI)

Atomic Spectroscopy Data Center. Summary: ... Atomic Spectroscopy Data Webpage. End Date: ongoing. Lead Organizational Unit: physlab. Contact. ...

2013-06-06T23:59:59.000Z

188

Process for production of an aluminum hydride compound  

SciTech Connect

A compound of formula M(AlH.sub.3OR.sup.1).sub.y, wherein R.sup.1 is phenyl substituted by at least one of: (i) an alkoxy group having from one to six carbon atoms; and (ii) an alkyl group having from three to twelve carbon atoms; wherein M is an alkali metal, Be or Mg; and y is one or two.

Allen, Nathan Tait; Butterick, III, Robert; Chin, Arthur Achhing; Miller, Dean Michael; Molzahn, David Craig

2013-08-06T23:59:59.000Z

189

Titanium tritide radioisotope heat source development : palladium-coated titanium hydriding kinetics and tritium loading tests.  

DOE Green Energy (OSTI)

We have found that a 180 nm palladium coating enables titanium to be loaded with hydrogen isotopes without the typical 400-500 C vacuum activation step. The hydriding kinetics of Pd coated Ti can be described by the Mintz-Bloch adherent film model, where the rate of hydrogen absorption is controlled by diffusion through an adherent metal-hydride layer. Hydriding rate constants of Pd coated and vacuum activated Ti were found to be very similar. In addition, deuterium/tritium loading experiments were done on stacks of Pd coated Ti foil in a representative-size radioisotope heat source vessel. The experiments demonstrated that such a vessel could be loaded completely, at temperatures below 300 C, in less than 10 hours, using existing department-of-energy tritium handling infrastructure.

Van Blarigan, Peter; Shugard, Andrew D.; Walters, R. Tom (Savannah River National Labs, Aiken, SC)

2012-01-01T23:59:59.000Z

190

High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides  

DOE Green Energy (OSTI)

This final report describes the motivations, activities and results of the hydrogen storage independent project "High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides" performed by the United Technologies Research Center under the Department of Energy Hydrogen Program, contract # DE-FC36-02AL67610. The objectives of the project were to identify and address the key systems technologies associated with applying complex hydride materials, particularly ones which differ from those for conventional metal hydride based storage. This involved the design, fabrication and testing of two prototype systems based on the hydrogen storage material NaAlH4. Safety testing, catalysis studies, heat exchanger optimization, reaction kinetics modeling, thermochemical finite element analysis, powder densification development and material neutralization were elements included in the effort.

Daniel A. Mosher; Xia Tang; Ronald J. Brown; Sarah Arsenault; Salvatore Saitta; Bruce L. Laube; Robert H. Dold; Donald L. Anton

2007-07-27T23:59:59.000Z

191

Automotive storage of hydrogen using modified magnesium hydrides. Final report, March 1976-March 1978  

DOE Green Energy (OSTI)

Metal hydrides can store more hydrogen per unit volume than normal high pressure or cryogenic techniques. Little energy is required to store the hydrogen in the hydride, and high stability at room temperature ensures low losses over long storage periods. Safety features of metal hydride storage are favorable. Because of its low weight and high hydrogen storage densities, modified magnesium hydride offers the greatest potential for automotive storage of hydrogen. Experimental and analytical work in this program has been directed toward the optimization of this storage system. Due to the relative stability of MgH/sub 2/, modifications of the MgMH/sub x/ (M = metal ion) have been made to decrease the dissociation temperature while retaining high hydrogen capacity. This parameter is crucial since vehicle exhaust will supply the thermal energy to dissociate the hydride in an automobile. System studies indicate that hydride dissociation temperature (T/sub D/) should be 200/sup 0/C to ensure uninterrupted fuel flow at all driving and idle conditions. From experimental data developed in this four task study, we conclude that alloys comprised of Mg, Cu and Ni have come closest to meeting the dissociation temperature goal. Small additions of rare-earth elements to the basic alloy also contribute to a reduction of T/sub D/. The best alloy developed in this program exhibits a T/sub D/ = 223/sup 0/C and a hydrogen capacity near four weight percent compared to a theoretical 7.65 percent for MgH/sub 2/. That alloy has been characterized for dissociation temperature, hydrogen capacity, kinetics, and P-C-T relationships. Dissociation temperature, hydrogen capacity and material cost are reported for each alloy tested in this program.

Rohy, D. A.; Nachman, J. F.; Hammer, A. N.; Duffy, T. E.

1979-01-01T23:59:59.000Z

192

Monitoring atom-atom entanglement and decoherence in a solvable tripartite open system in cavity QED  

E-Print Network (OSTI)

We present a fully analytical solution of the dynamics of two strongly-driven atoms resonantly coupled to a dissipative cavity field mode. We show that an initial atom-atom entanglement cannot be increased. In fact, the atomic Hilbert space divides into two subspaces, one of which is decoherence free so that the initial atomic entanglement remains available for applications, even in presence of a low enough atomic decay rate. In the other subspace a measure of entanglement, decoherence, and also purity, are described by a similar functional behavior that can be monitored by joint atomic measurements. Furthermore, we show the possible generation of Schr\\"odinger-cat-like states for the whole system in the transient regime, as well as of entanglement for the cavity field and the atom-atom subsystems conditioned by measurements on the complementary subsystem.

Matteo Bina; Federico Casagrande; Alfredo Lulli; Enrique Solano

2007-11-08T23:59:59.000Z

193

Single artificial-atom lasing  

E-Print Network (OSTI)

Solid-state superconducting circuits are versatile systems in which quantum states can be engineered and controlled. Recent progress in this area has opened up exciting possibilities for exploring fundamental physics as well as applications in quantum information technology; in a series of experiments it was shown that such circuits can be exploited to generate quantum optical phenomena, by designing superconducting elements as artificial atoms that are coupled coherently to the photon field of a resonator. Here we demonstrate a lasing effect with a single artificial atom - a Josephson-junction charge qubit - embedded in a superconducting resonator. We make use of one of the properties of solid-state artificial atoms, namely that they are strongly and controllably coupled to the resonator modes. The device is essentially different from existing lasers and masers; one and the same artificial atom excited by current injection produces many photons.

O. Astafiev; K. Inomata; A. O. Niskanen; T. Yamamoto; Yu. A. Pashkin; Y. Nakamura; J. S. Tsai

2007-10-04T23:59:59.000Z

194

INVESTIGATION OF THE THERMODYNAMICS GOVERNING METAL HYDRIDE SYNTHESIS IN THE MOLTEN STATE PROCESS.  

Science Conference Proceedings (OSTI)

Complex metal hydrides have been synthesized for hydrogen storage through a new synthetic technique utilizing high hydrogen overpressure at elevated temperatures (molten state processing). This synthesis technique holds the potential of fusing different complex hydrides at elevated temperatures and pressures to form new species with enhanced hydrogen storage properties. Formation of these compounds is driven by thermodynamic and kinetic considerations. We report on investigations of the thermodynamics. Novel synthetic complexes were formed, structurally characterized, and their hydrogen desorption properties investigated. The effectiveness of the molten state process is compared with mechanicosynthetic ball milling.

Stowe, A; Polly Berseth, P; Ragaiy Zidan, R; Donald Anton, D

2007-08-23T23:59:59.000Z

195

Lesson 6- Atoms to Electricity  

Energy.gov (U.S. Department of Energy (DOE))

Most power plants make electricity by boiling water to make steam that turns a turbine. A nuclear power plant works this way, too. At a nuclear power plant, splitting atoms produce the heat to boil the water. This lesson covers inside the reactor, fission control and electricity generation.

196

Evaluation of Protected Metal Hydride Slurries in a H2 Mini-  

E-Print Network (OSTI)

Evaluation of Protected Metal Hydride Slurries in a H2 Mini- Grid TIAX, LLC Acorn Park Cambridge_MERIT_REVIEW_MAY2003 2 Introduction Hydrogen Mini-Grid Concept Distributed FCPS utilizing a H2 Mini-Grid can provide waste heat can be used for hot water or space heating in buildings (i.e. "cogen") Distributed FCPS

197

Model for the Prediction of the Hydriding Thermodynamics of Pd-Rh-Co Ternary Alloys  

DOE Green Energy (OSTI)

A dilute solution model (with respect to the substitutional alloying elements) has been developed, which accurately predicts the hydride formation and decomposition thermodynamics and the storage capacities of dilute ternary Pd-Rh-Co alloys. The effect of varying the rhodium and cobalt compositions on the thermodynamics of hydride formation and decomposition and hydrogen capacity of several palladium-rhodium-cobalt ternary alloys has been investigated using pressure-composition (PC) isotherms. Alloying in the dilute regime (<10 at.%) causes the enthalpy for hydride formation to linearly decrease with increasing alloying content. Cobalt has a stronger effect on the reduction in enthalpy than rhodium for equivalent alloying amounts. Also, cobalt reduces the hydrogen storage capacity with increasing alloying content. The plateau thermodynamics are strongly linked to the lattice parameters of the alloys. A near-linear dependence of the enthalpy of hydride formation on the lattice parameter was observed for both the binary Pd-Rh and Pd-Co alloys, as well as for the ternary Pd-Rh-Co alloys. The Pd-5Rh-3Co (at. %) alloy was found to have similar plateau thermodynamics as a Pd-10Rh alloy, however, this ternary alloy had a diminished hydrogen storage capacity relative to Pd-10Rh.

Teter, D.F.; Thoma, D.J.

1999-03-01T23:59:59.000Z

198

Lithium hydride and lithium amide for hydrogen storage J. Engbk, G. Nielsen, I. Chorkendorff  

E-Print Network (OSTI)

Lithium hydride and lithium amide for hydrogen storage J. Engbæk, G. Nielsen, I. Chorkendorff 1 interest. Lithium amid has a high hydrogen storage capability; 10.4wt.% hydrogen. In this study surface reactions of thin films of lithium with hydrogen and ammonia is studied under well controlled conditions

Mosegaard, Klaus

199

STANDARDIZED TESTING PROGRAM FOR EMERGENT CHEMICAL HYDRIDE AND CARBON STORAGE TECHNOLOGIES  

E-Print Network (OSTI)

hydride/carbon hydrogen storage systems. The development of a standardized protocol and testing system to an urgent need for accelerated development of hydrogen storage systems. In vehicular applications, hydrogen storage and distribution presents the greatest challenge in creating the hydrogen fuel infrastructure

200

Transition from LEDCOP to ATOMIC  

SciTech Connect

This paper discusses the development of the ATOMIC code, a new low to mid Z opacity code, which will replace the current Los Alamos low Z opacity code LEDCOP. The ATOMIC code is based on the FINE code, long used by the Los Alamos group for spectral comparisons in local thermodynamic equilibrium (LTE) and for non-LTE calculations, both utilizing the extensive databases from the atomic physics suite of codes based on the work of R.D. Cowan. Many of the plasma physics packages in LEDCOP, such as line broadening and free-free absorption, are being transferred to the new ATOMIC code. A new equation of state (EOS) model is being developed to allow higher density calculations than were possible with either the FINE or LEDCOP codes. Extensive modernization for both ATOMIC and the atomic physics code suites, including conversion to Fortran 90 and parallelization, are underway to speed up the calculations and to allow the use of expanded databases for both the LTE opacity tables and the non-LTE calculations. Future plans for the code will be outlined, including considerations for new generation opacity tables.

Magee, N. H. (Norman H.); Abdallah, J. (Joseph); Colgan, J. (James); Hakel, P. (Peter); Kilcrease, D. P. (David P.); Mazevet, S. (Stephane); Sherrill, M. E. (Manolo E.); Fontes, C. J. (Christopher J.); Zhang, H. (Honglin)

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Tritium storage development. Progress report No. 10, October--December 1976. [In metal hydride; polymer-impregnated tritiated concrete  

DOE Green Energy (OSTI)

Laboratory and engineering scale work has been initiated on the storage of tritium in a metal hydride. Laboratory hydriding apparatus has been assembled and a preliminary series of experiments was carried out on zirconium. Several engineering design concepts for the reaction and storage of tritium in a metal hydride are presented. The design of a three 3-in.-diam. bench scale reaction system is in progress. Developmental work is continuing on the injector technique for the fixation of tritium in polymer-impregnated concrete.

Colombo, P; Steinberg, M

1976-01-01T23:59:59.000Z

202

Supercomputers and atomic physics data  

SciTech Connect

The advent of the supercomputer has dramatically increased the possibilities for generating and using massive amounts of detailed fine structure atomic physics data. Size, speed, and software have made calculations which were impossible just a few years ago into a reality. Further technological advances make future possibilities seem endless. The cornerstone atomic structure codes of R.D. Cowan have been adapted into a single code CATS for use on Los Alamos supercomputers. We provide a brief overview of the problem; and report a sample CATS calculation using configuration interaction to calculate collision and oscillator strengths for over 300,000 transitions in neutral nitrogen. We also discuss future supercomputer needs. 2 refs.

Abdallah, J. Jr.; Clark, R.E.H.

1988-01-01T23:59:59.000Z

203

Atomic Reference Data for Electronic Structure Calculations - TMS  

Science Conference Proceedings (OSTI)

Feb 7, 2007 ... For this resource, data have been generated for atomic electronic structure calculations, to provide a standard reference for results of specified...

204

NIST Ytterbium Atomic Clocks Set Record for Stability  

Science Conference Proceedings (OSTI)

... Ytterbium atoms are generated in an oven (large metal cylinder on the left) and sent to a vacuum chamber in the center of the photo to be ...

2013-08-22T23:59:59.000Z

205

NIST: Atomic Reference Data for Electronic Structure Calc.  

Science Conference Proceedings (OSTI)

... We have generated data for atomic electronic structure calculations, to ... are presented here for total energies and orbital energy eigenvalues for ...

2011-12-09T23:59:59.000Z

206

Role of electronic, geometric, and surface properties on the mechanism of the electrochemical hydriding/dehydriding reactions  

DOE Green Energy (OSTI)

Since 1990 there has been an ongoing collaboration among the authors to investigate the role of individual elements on the thermodynamics and kinetics of hydriding/dehydriding reactions. This review article presents the electrochemical and physicochemical characteristics of hydriding/dehydriding reactions from the point of view of their dependence on electronic, geometric and surface properties of the hydride materials. X-ray absorption spectroscopy (XAS), x-ray diffraction spectroscopy (XRD) and scanning vibrating electrode technique (SVET) studies were based on AB{sub 5} type alloys, partially substituted by other elements. Expansion of the unit cell volume and a larger Ni d band vacancy are beneficial for increasing the amount of the hydrogen storage. XAS and SVET showed that the Ce substitution for La in an AB{sub 5} alloy enhances the lifetime of hydride electrode.

Srinivasan, S.; Zhang, W.; Kumar, M.P.S. [Texas A and M Univ., College Station, TX (United States). Texas Engineering Experiment Station] [and others

1996-03-01T23:59:59.000Z

207

Metal Hydrides for Thermal Energy Storage Applications - A review  

Science Conference Proceedings (OSTI)

Symposium, Energy Storage: Materials, Systems and Applications. Presentation Title ... Hydrogen Generation Using Cyclic Redox Reaction of Iron Oxide ... The Effect the Distribution of the Conducting Phase on SiCO-Li+ Anode Performance.

208

Method of performing MRI with an atomic magnetometer  

SciTech Connect

A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

Savukov, Igor Mykhaylovich; Matlashov, Andrei Nikolaevich; Espy, Michelle A; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry; Zotev, Vadim Sergeyevich

2013-08-27T23:59:59.000Z

209

Method of performing MRI with an atomic magnetometer  

DOE Patents (OSTI)

A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

Savukov, Igor Mykhaylovich; Matlashov, Andrei Nikolaevich; Espy, Michelle A.; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry; Zotev, Vadim Sergeyevich

2012-11-06T23:59:59.000Z

210

New plasma source of hydrides for epitaxial growth. Final subcontract report, 15 April 1991--3 September 1993  

DOE Green Energy (OSTI)

This report describes a novel plasma-activated selenium source that was developed during the course of this subcontract and which is significantly different than any other heretofore reported in the scientific literature. It involves microwave excited, magnetically confined plasma sources that are intended to operate under electron cyclotron resonance (ECR) conditions at 2.455 GHz. This source is designed to excite and dissociate the molecular vapor evaporating or subliming from a heated solid or liquid reservoir. It can combine an effusion cell vapor flux with a stream of hydrogen or helium gas, enabling the in-situ generation of hydrides for use in low-pressure growth techniques where long mean free paths are desirable. Experiments were conducted to demonstrate a stable discharge within the source, and measures were identified to improve its operational characteristics. Application of this novel source is anticipated to enable a low-temperature, safe process for the growth of high-quality epitaxial compound semiconductor films. This reduction of epitaxial growth temperatures may enable the fabrication of novel photovoltaic devices that have heretofore been impossible due to the deleterious effects of interdiffusion at heterointerfaces resulting from the high temperatures required to grow adequate quality material using conventional processes.

Stanbery, B.J. [Boeing Defense & Space Group, Seattle, WA (United States)

1994-05-01T23:59:59.000Z

211

Nickel-Metal-Hydride Batterie--High Energy Storage for Electric Vehicles  

NLE Websites -- All DOE Office Websites (Extended Search)

Freedomcar & Vehicle Technologies Program Freedomcar & Vehicle Technologies Program Nickel-Metal-Hydride Batteries - High Energy Storage for Electric Vehicles Background The key to making electric vehicles (EVs) practical is the development of batteries that can provide performance comparable with that of con ventional vehicles at a similar cost. Most EV batteries have limited energy storage capabili ties, permitting only relatively short driving distances before the batteries must be recharged. In 1991, under a coopera tive agreement with The U.S. Department of Energy (DOE), the United States Advanced Battery Consortium (USABC) initiated development of nickel- metal-hydride (NiMH) battery technology and established it as a prime mid-term candidate for use in EVs. DOE funding has been instru

212

Aluminum Hydride - DOE Hydrogen and Fuel Cells Program FY 2012 Annual Progress Report  

NLE Websites -- All DOE Office Websites (Extended Search)

1 1 FY 2012 Annual Progress Report DOE Hydrogen and Fuel Cells Program Jason Graetz (Primary Contact), James Wegrzyn Brookhaven National Laboratory (BNL) Building 815 Upton, NY 11973 Phone: (631) 344-3242 Email: graetz@bnl.gov DOE Manager HQ: Ned Stetson Phone: (202) 586-9995 Email: Ned.Stetson@ee.doe.gov Project Start Date: October 1, 2011 Project End Date: Project continuation and direction determined annually by DOE Fiscal Year (FY) 2012 Objectives Develop onboard vehicle storage systems using aluminum hydride that meets all of DOE's targets for proton exchange membrane fuel cell vehicles. Produce aluminum hydride material with a hydrogen * storage capacity greater than 9.7% gravimetric (kg-H 2 /kg) and 0.13 kg-H 2 /L volumetric. Develop practical and economical processes for *

213

Pressure Acceleration of Hydride Formation on a Cobalt(I) Macrocycle  

NLE Websites -- All DOE Office Websites (Extended Search)

Pressure Acceleration of Hydride Formation via Pressure Acceleration of Hydride Formation via Proton Binding to a Cobalt(I) Macrocycle Etsuko Fujita, James F. Wishart, and Rudi van Eldik Inorg. Chem. 41, 1579-1583 (2002) [Find paper at ACS Publications] Abstract: The effect of pressure on proton binding to the racemic isomer of the cobalt(I) macrocycle, CoL+ (L = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene), has been studied for a series of proton donors using pulse radiolysis techniques. The second-order rate constants for the reaction of CoL+ with proton donors decrease with increasing pKa of the donor acid, consistent with a reaction occurring via proton transfer. Whereas the corresponding volumes of activation (DVý) are rather small and negative for all acids (proton donors) with pKa values below 8.5, significantly larger negative

214

Method to predict relative hydriding within a group of zirconium alloys under nuclear irradiation  

DOE Patents (OSTI)

An out-of-reactor method for screening to predict relative in-reactor hydriding behavior of zirconium-based materials is disclosed. Samples of zirconium-based materials having different compositions and/or fabrication methods are autoclaved in a relatively concentrated (0.3 to 1.0M) aqueous lithium hydroxide solution at constant temperatures within the water reactor coolant temperature range (280 to 316 C). Samples tested by this out-of-reactor procedure, when compared on the basis of the ratio of hydrogen weight gain to oxide weight gain, accurately predict the relative rate of hydriding for the same materials when subject to in-reactor (irradiated) corrosion. 1 figure.

Johnson, A.B. Jr.; Levy, I.S.; Trimble, D.J.; Lanning, D.D.; Gerber, F.S.

1990-04-10T23:59:59.000Z

215

RESEARCH AND DEVELOPMENT OF METAL HYDRIDES. Summary Report for October 1, 1958-September 30, 1960  

DOE Green Energy (OSTI)

A detailed study of the fundamental relations in the zirconium -- hydrogen system was made in order to clarify the many points of dispute and to evolve a complete picture describing all phases of this system. An engineering evaluation was made of means for utillzing the various high cross-section metal hydrides in shielding or control applications. These materials would combine the processes of thermalization and absorption. Consequently, they are of considerable interest for use in shielding or controlling epithermal reactors. (auth)

Beck, R.L.

1960-11-01T23:59:59.000Z

216

Develop improved metal hydride technology for the storage of hydrogen. Final technical report  

DOE Green Energy (OSTI)

The overall objective was to develop commercially viable metal hydrides capable of reversibly storing at least 3 wt.% hydrogen for use with PEM fuel cells and hydrogen fueled internal combustion engine (HICE) applications. Such alloys are expected to result in system capacities of greater than 2 wt.%, making metal hydride storage systems (MHSS`s) a practical means of supplying hydrogen for many consumer applications. ECD`s (Energy Conversion Devices, Inc.) past work on sputtered thin films of transition metal-based alloys led to the commercialization of it`s nickel/metal hydride batteries, and similar work on thin film Mg-based alloys demonstrated potential to achieve very high gravimetric and volumetric energy densities approaching 2,500 Wh/Kg and 2,500 Wh/M{sup 3} respectively. Under this 2-year cost shared project with the DOE, the authors have successfully demonstrated the feasibility of scaling up the Mg-based hydrides from thin film to bulk production without substantial loss of storage capacity. ECD made progress in alloy development by means of compositional and process modification. Processes used include Mechanical Alloying, Melt spinning and novel Gas Phase Condensation. It was showed that the same composition when prepared by melt-spinning resulted in a more homogeneous material having a higher PCT plateau pressure as compared to mechanical alloying. It was also shown that mechanically alloyed Mg-Al-Zn results in much higher plateau pressures, which is an important step towards reducing the desorption temperature. While significant progress has been made during the past two years in alloy development and understanding the relationship between composition, structure, morphology, and processing parameters, additional R and D needs to be performed to achieve the goals of this work.

Sapru, K.

1998-12-04T23:59:59.000Z

217

Correlated Quantum Memory: Manipulating Atomic Entanglement via Electromagnetically Induced Transparency  

E-Print Network (OSTI)

We propose a feasible scheme of quantum state storage and manipulation via electromagnetically induced transparency (EIT) in flexibly $united$ multi-ensembles of three-level atoms. For different atomic array configurations, one can properly steer the signal and the control lights to generate different forms of atomic entanglement within the framework of linear optics. These results shed new light on designing the versatile quantum memory devices by using, e.g., an atomic grid.

H. Jing; X. -J. Liu; M. -L. Ge; M. -S. Zhan

2004-10-05T23:59:59.000Z

218

Non-stoichiometric AB5 alloys for metal hydride electrodes  

DOE Patents (OSTI)

The present invention provides a non-stoichiometric alloy comprising a composition having the formula AB.sub.5+X an atomic ratio wherein A is selected from the group consisting of the rare earth metals, yttrium, mischmetal, or a combination thereof; B is nickel and tin, or nickel and tin and at least a third element selected from the group consisting of the elements in group IVA of the periodic table, aluminum, manganese, iron, cobalt, copper, antimony or a combination thereof; X is greater than 0 and less than or equal to about 2.0; and wherein at least one substituted A site is occupied by at least one of the B elements. An electrode incorporating said alloy and an electrochemical cell incorporating said electrode are also described.

Reilly, James J. (Bellport, NY); Adzic, Gordana D. (Setauket, NY); Johnson, John R. (Calverton, NY); Vogt, Thomas (Cold Spring Harbor, NY); McBreen, James (Bellport, NY)

2001-01-01T23:59:59.000Z

219

Systems Modeling, Simulation and Material Operating Requirements for Chemical Hydride Based Hydrogen Storage  

Science Conference Proceedings (OSTI)

Research on ammonia borane (AB, NH3BH3) has shown it to be a promising material for chemical hydride based hydrogen storage. AB was selected by DOE's Hydrogen Storage Engineering Center of Excellence (HSECoE) as the initial chemical hydride of study because of its high hydrogen storage capacity (up to 19.6% by weight for the release of {approx}2.5 molar equivalents of hydrogen gas) and its stability under typical ambient conditions. A new systems concept based on augers, ballast tank, hydrogen heat exchanger and H2 burner was designed and implemented in simulation. In this design, the chemical hydride material was assumed to produce H2 on the augers itself, thus minimizing the size of ballast tank and reactor. One dimensional models based on conservation of mass, species and energy were used to predict important state variables such as reactant and product concentrations, temperatures of various components, flow rates, along with pressure, in various components of the storage system. Various subsystem components in the models were coded as C language S-functions and implemented in Matlab/Simulink environment. The control variable AB (or alane) flow rate was determined through a simple expression based on the ballast tank pressure, H2 demand from the fuel cell and hydrogen production from AB (or alane) in the reactor. System simulation results for solid AB, liquid AB and alane for both steady state and transient drive cycle cases indicate the usefulness of the model for further analysis and prototype development.

Devarakonda, Maruthi N.; Brooks, Kriston P.; Ronnebro, Ewa; Rassat, Scot D.

2012-02-01T23:59:59.000Z

220

Method for the prediction of the hydriding thermodynamics of ternary PD-based alloys.  

DOE Green Energy (OSTI)

A method has been developed to calculate the hydriding thermodynamics of ternary Pd-X-Y systems, where X and Y are substitutional alloying elements, by using the properties of the binary Pd-X and Pd-Y systems. Experimental data was collected on the Pd-Rh-Co system to test the validity of this method. Hydrogen pressure-composition isotherms of several binary Pd-Rh and Pd-Co alloys and Pd-Rh-Co ternary alloys were measured to determine the thermodynamics of hydrogen absorption, hydride formation and decomposition, and hydrogen capacity. Good agreement between the calculated and measured values for the ternary Pd-Rh-Co system, in the dilute alloying regime (< 10 at.% total alloying additions), was obtained using our method. Examining literature results on other ternary Pd-X-Y systems checked the universality of this method. Again, the method succeeds in predicting the hydriding thermodynamics for both lattice contracted and lattice expanded alloy systems, Pd-Ni-Rh and Pd-Ag-Y respectively.

Teter, D. F. (David F.); Mauro, M. E. (Michael Ernest)

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Theoretical Atomic Physics code development IV: LINES, A code for computing atomic line spectra  

SciTech Connect

A new computer program, LINES, has been developed for simulating atomic line emission and absorption spectra using the accurate fine structure energy levels and transition strengths calculated by the (CATS) Cowan Atomic Structure code. Population distributions for the ion stages are obtained in LINES by using the Local Thermodynamic Equilibrium (LTE) model. LINES is also useful for displaying the pertinent atomic data generated by CATS. This report describes the use of LINES. Both CATS and LINES are part of the Theoretical Atomic PhysicS (TAPS) code development effort at Los Alamos. 11 refs., 9 figs., 1 tab.

Abdallah, J. Jr.; Clark, R.E.H.

1988-12-01T23:59:59.000Z

222

Reading Comprehension - Atomic History  

NLE Websites -- All DOE Office Websites (Extended Search)

Atomic History Atomic History A Greek philosopher named Democritus said that all atoms are small, hard particles. He thought that atoms were made of a single material formed into different shapes and sizes. The word " _________ element compound mixture atom " is derived from the Greek word "atomos" which means "not able to be divided." In 1803, John Dalton, a school teacher, proposed his atomic theory. Dalton's theory states that elements (substances composed of only one type of _________ molecules ions atom ) combine in certain proportions to form _________ compounds atoms mixtures elements . In 1897, a British scientist named J. J. Thomson experimented with a cathode-ray tube which had a positively charged plate. The plate attracted negatively charged particles that we now call _________ protons neutrons

223

Atomic and Molecular Physics  

Science Conference Proceedings (OSTI)

... DG, * SRD 105 Physic Laboratory's Elemental ... Nuclear Physics SRD 144 Atomic Weights & ... Physical Constants SRD 121 Fundamental Physical ...

2012-10-10T23:59:59.000Z

224

Atomizing nozzle and process  

DOE Patents (OSTI)

High pressure atomizing nozzle includes a high pressure gas manifold having a divergent expansion chamber between a gas inlet and arcuate manifold segment to minimize standing shock wave patterns in the manifold and thereby improve filling of the manifold with high pressure gas for improved melt atomization. The atomizing nozzle is especially useful in atomizing rare earth-transition metal alloys to form fine powder particles wherein a majority of the powder particles exhibit particle sizes having near-optimum magnetic properties.

Anderson, I.E.; Figliola, R.S.; Molnar, H.M.

1993-07-20T23:59:59.000Z

225

Calibrated Atomic Force Microscopy  

Science Conference Proceedings (OSTI)

... Vorburger, SL Tan, NG Orji, J. Fu, Interlaboratory Comparison of Traceable Atomic Force Microscope Pitch Measurements, SPIE Proceedings Vol. ...

2011-10-28T23:59:59.000Z

226

Manhattan Project: Atomic Bombardment, 1932-1938  

Office of Scientific and Technical Information (OSTI)

Solvay Physics Conference, Brussels, October 1933 ATOMIC BOMBARDMENT Solvay Physics Conference, Brussels, October 1933 ATOMIC BOMBARDMENT (1932-1938) Events > Atomic Discoveries, 1890s-1939 A Miniature Solar System, 1890s-1919 Exploring the Atom, 1919-1932 Atomic Bombardment, 1932-1938 The Discovery of Fission, 1938-1939 Fission Comes to America, 1939 M. Stanley Livingston and Ernest O. Lawrence in front of a 27-inch cyclotron, Rad Lab, University of California, Berkeley, 1934. In the 1930s, scientists learned a tremendous amount about the structure of the atom by bombarding it with sub-atomic particles. Ernest O. Lawrence's cyclotron, the Cockroft-Walton machine, and the Van de Graaff generator, developed by Robert J. Van de Graaff at Princeton University, were particle accelerators designed to bombard the nuclei of various elements to disintegrate atoms. Attempts of the early 1930s to split atoms, however, required huge amounts of energy because the first accelerators used proton beams and alpha particles as sources of energy. Since protons and alpha particles are positively charged, they Albert Einstein met substantial resistance from the positively charged target nucleus when they attempted to penetrate atoms. Even high-speed protons and alpha particles scored direct hits on a nucleus only approximately once in a million tries. Most simply passed by the target nucleus. Not surprisingly, Ernest Rutherford, Albert Einstein (right), and Niels Bohr regarded particle bombardment as useful in furthering knowledge of nuclear physics but believed it unlikely to meet public expectations of harnessing the power of the atom for practical purposes anytime in the near future. In a 1933 interview, Rutherford called such expectations "moonshine." Einstein compared particle bombardment with shooting in the dark at scarce birds, while Bohr, the Danish Nobel laureate, agreed that the chances of taming atomic energy were remote.

227

Atomic Data for Mercury (Hg)  

Science Conference Proceedings (OSTI)

... Mercury (Hg) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Mercury (Hg). ...

228

Atomic Data for Plutonium (Pu)  

Science Conference Proceedings (OSTI)

... Plutonium (Pu) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Plutonium (Pu). ...

229

Atomic Data for Tungsten (W )  

Science Conference Proceedings (OSTI)

... Tungsten (W) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Tungsten (W). ...

230

Atomic Data for Uranium (U )  

Science Conference Proceedings (OSTI)

... Uranium (U) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Uranium (U). ...

231

Atomic Data for Hydrogen (H )  

Science Conference Proceedings (OSTI)

... Hydrogen (H) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Hydrogen (H). ...

232

Atomic Data for Thorium (Th)  

Science Conference Proceedings (OSTI)

... Thorium (Th) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Thorium (Th). ...

233

Mathematical model of a NiOOH/metal hydride cell. Final report, September 15, 1993--November 14, 1996  

DOE Green Energy (OSTI)

One of the objectives of work on the nickel/metal hydride cell has been to develop a mathematical model of the performance of the cell. This is a summary of work to date and is meant to be a Final Report of the BES project. Mathematical model of the nickel/metal hydride cell depends on the kinetics, thermodynamics, and transport properties of the metal hydride electrode. Consequently, investigations were carried out to determine: (1) the exchange current density and the equilibrium potential as a function of hydrogen content in the electrode; (2) the hydrogen diffusion coefficient in the bulk of the alloy; (3) the hydrogen reaction rate order; (4) the symmetry factor for hydrogen evolution reaction and (5) to determine the reaction mechanisms of the hydrogen charge and discharge processes including overcharge and overdischarge mechanism.

White, R.E.; Popov, B.N.

1996-12-31T23:59:59.000Z

234

Postirradiation examination of pressure tubes 2954 and 3053: Corrosion, hydriding and fluence measurements  

Science Conference Proceedings (OSTI)

Pressure Tubes 2954 and 3053 were removed from N Reactor in March 1987 for postirradiation examinations (PIE) including hydriding, corrosion, fluence and mechanical property measurements. The results of the corrosion, hydriding, and fluence measurements are the subject of this report. These data will be used to evaluate the trends in corrosion and hydriding behavior which are important to the structural integrity of these tubes. The trend evaluations as well as the mechanical property data are or will be reported elsewhere. Both tubes operated at high power accumulating 101,800 hours of service since reactor startup in 1964. Fabricated by the Harvey Aluminum Company, Tube 2954 was cold drawn to 30% reduction of area as were 86% of the reactor tubes. Tube 3053 was also a Harvey Tube but was cold worked 18% representing 2.5% of the reactor tubes. Corrosion measurements were made from metallographic sections. The inner surface oxide thickness peaks at 2 to 5 ft downstream of the center of the fueled zone. This profile is typical of previous examined N Reactor pressure tubes. The maximum measured oxide thickness on tube 2954 was 64 microns, 17% greater than for tubes removed in 1984. The corrosion product hydrogen that is absorbed by the tube has distribution gradients in the azimuthal, axial, and radial directions. Radical surveys confirmed previous observations that most of the hydrogen is concentrated near the tube ID surfaces. For Tubes 2954 and 3053, 50% to 80% of the hydrogen is found in 20% of the tube wall. The radial as well as the azimuthal gradients are caused by thermal gradients in the tubes, with the hydrogen redistributing to the cooler parts of the tube wall. 6 refs., 50 figs., 2 tabs.

Chastain, S.A.; Trimble, D.J.; Boyd, S.M.

1988-06-01T23:59:59.000Z

235

Metal hydride/chemical heat-pump development project. Phase I. Final report  

DOE Green Energy (OSTI)

The metal hydride/chemical heat pump (MHHP) is a chemical heat pump containing two hydrides for the storage and/or recovery of thermal energy. It utilizes the heat of reaction of hydrogen with specific metal alloys. The MHHP design can be tailored to provide heating and/or cooling or temperature upgrading over a wide range of input and ambient temperatures. The system can thus be used with a variety of heat sources including waste heat, solar energy or a fossil fuel. The conceptual design of the MHHP was developed. A national market survey including a study of applications and market sectors was conducted. The technical tasks including conceptual development, thermal and mechanical design, laboratory verification of design and material performance, cost analysis and the detailed design of the Engineering Development Test Unit (EDTU) were performed. As a result of the market study, the temperature upgrade cycle of the MHHP was chosen for development. Operating temperature ranges for the upgrader were selected to be from 70 to 110/sup 0/C (160 to 230/sup 0/F) for the source heat and 140 to 190/sup 0/C (280 to 375/sup 0/F) for the product heat. These ranges are applicable to many processes in industries such as food, textile, paper and pulp, and chemical. The hydride pair well suited for these temperatures is LaNi/sub 5//LaNi/sub 4/ /sub 5/Al/sub 0/ /sub 5/. The EDTU was designed for the upgrade cycle. It is a compact finned tube arrangement enclosed in a pressure vessel. This design incorporates high heat transfer and low thermal mass in a system which maximizes the coefficient of performance (COP). It will be constructed in Phase II. Continuation of this effort is recommended.

Argabright, T.A.

1982-02-01T23:59:59.000Z

236

ATOMS PEACE WAR Eisenhower  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

ATOMS ATOMS PEACE WAR Eisenhower and the Atomic Energy Commission Richard G. Hewlett and lack M. Roll With a Foreword by Richard S. Kirkendall and an Essay on Sources by Roger M. Anders University of California Press Berkeley Los Angeles London Published 1989 by the University of California Press Berkeley and Los Angeles, California University of California Press, Ltd. London, England Prepared by the Atomic Energy Commission; work made for hire. Library of Congress Cataloging-in-Publication Data Hewlett, Richard G. Atoms for peace and war, 1953-1961. (California studies in the history of science) Bibliography: p. Includes index. 1. Nuclear energy-United States-History. 2. U.S. Atomic Energy Commission-History. 3. Eisenhower, Dwight D. (Dwight David), 1890-1969.

237

Thermodynamic Guidelines for the Prediction of Hydrogen Storage Reactions and Their Application to Destabillzed Hydride Mixtures  

NLE Websites -- All DOE Office Websites (Extended Search)

Thermodynamic guidelines for the prediction of hydrogen Thermodynamic guidelines for the prediction of hydrogen storage reactions and their application to destabilized hydride mixtures Hydrogen Storage & Nanoscale Modeling Group Ford Motor Company Don Siegel dsiegel2@ford.com Phys. Rev. B 76, 134102 (2007) 1 Acknowledgements C. Wolverton V. Ozolins Computation Northwestern UCLA J. Yang A. Sudik Experiments Ford Ford 2 Computational Methodology * Atomistic computer simulations based on quantum mechanics (Density Functional Theory) * First-principles approach: - Only empirical input are crystal structure and fundamental physical constants - VASP code - PAW potentials - PW91 GGA - Temperature-dependent thermodynamic contributions evaluated within harmonic approximation * "Direct method" for construction of dynamical matrix

238

Self-discharge mechanism of sealed-type nickel/metal-hydride battery  

Science Conference Proceedings (OSTI)

Factors affecting the self-discharge rate of a nickel/metal-hydride (Ni-MH) battery, generally much higher than that of nickel/cadmium (Ni-Cd) battery, are investigated, and the self-discharge mechanism is discussed. Ammonia and amine participate in the shuttle reaction like nitrate ion in the Ni-Cd battery, resulting in acceleration of the self-discharge. When nonwoven fabric made of sulfonated-polypropylene is used as a separator instead of conventional polyamide separator, the self-discharge rate of the Ni-MH battery is strongly depressed, to the same level as that of Ni-Cd battery.

Ikoma, Munehisa; Hoshina, Yasuko; Matsumoto, Isao [Matsushita Battery Industrial Co., Ltd., Osaka (Japan); Iwakura, Chiaki [Univ. of Osaka Prefecture, Sakai, Osaka (Japan). Dept. of Applied Chemistry

1996-06-01T23:59:59.000Z

239

High cycle life, cobalt free, AB{5} metal hydride electrodes [Revised 11/10/98  

SciTech Connect

Cobalt-free La(Ni,Sn)5+x alloys have been identified as low cost, corrosion resistant electrodes for nickel-metal-hydride batteries. The structure of theses alloys are similar to non-stoichiometric La(Ni,Cu)5+x compounds; i.e., they retain the P6/mmm space group while Ni dumbbells occupy La sites. Electrodes fabricated from some of these novel alloys have capacities and cycle lives equivalent to those made from commercial, battery grade, AB5 alloys with cobalt.

Vogt, Tom; Reilly, J.J.; Johnson, J.R.; Adzic, G.D.; Ticianelli, E.A.; Mukerjee, S.; McBreen, J.

1998-11-10T23:59:59.000Z

240

Metal atom oxidation laser  

DOE Patents (OSTI)

A chemical laser which operates by formation of metal or carbon atoms and reaction of such atoms with a gaseous oxidizer in an optical resonant cavity is described. The lasing species are diatomic or polyatomic in nature and are readily produced by exchange or other abstraction reactions between the metal or carbon atoms and the oxidizer. The lasing molecules may be metal or carbon monohalides or monoxides. (auth)

Jensen, R.J.; Rice, W.W.; Beattie, W.H.

1975-10-28T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Metal atom oxidation laser  

DOE Patents (OSTI)

A chemical laser which operates by formation of metal or carbon atoms and reaction of such atoms with a gaseous oxidizer in an optical resonant cavity is described. The lasing species are diatomic or polyatomic in nature and are readily produced by exchange or other abstraction reactions between the metal or carbon atoms and the oxidizer. The lasing molecules may be metal or carbon monohalides or monoxides.

Jensen, R.J.; Rice, W.W.; Beattie, W.H.

1975-10-28T23:59:59.000Z

242

Atomic Spectroscopy: An Introduction  

Science Conference Proceedings (OSTI)

... 60. A. de-Shalit and I. Talmi, Nuclear Shell Theory (Academic, New York, 1963). ... CE Moore, Atomic Energy Levels, Natl. Stand. Ref. ...

243

NIST Atomic Spectra Database  

Science Conference Proceedings (OSTI)

... Ground states and ionization energies of atoms ... the US Department of Energy, by the ... SRDP), and by NIST's Systems Integration for Manufacturing ...

2013-09-12T23:59:59.000Z

244

Cold Atoms News  

Science Conference Proceedings (OSTI)

... the first time caused a gas of atoms ... mysterious data in ultracold gases of rubidium ... Material May Demonstrate Long-Sought 'Liquid' Magnetic State ...

2010-10-20T23:59:59.000Z

245

Atomic Collapse Observed  

NLE Websites -- All DOE Office Websites (Extended Search)

Collapse State Observed Aided by Simulations, Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 |...

246

The Harnessed Atom  

Energy.gov (U.S. Department of Energy (DOE))

The Harnessed Atom is a new middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on nuclear science and energy. It offers teachers accurate, unbiased,...

247

EXPERIMENTAL RESULTS FOR THE ISOTOPIC EXCHANGE OF A 1600 LITER TITANIUM HYDRIDE STORAGE VESSEL  

Science Conference Proceedings (OSTI)

Titanium is used as a low pressure tritium storage material. The absorption/desorption rates and temperature rise during air passivation have been reported previously for a 4400 gram prototype titanium hydride storage vessel (HSV). A desorption limit of roughly 0.25 Q/M was obtained when heating to 700 C which represents a significant residual tritium process vessel inventory. To prepare an HSV for disposal, batchwise isotopic exchange has been proposed to reduce the tritium content to acceptable levels. A prototype HSV was loaded with deuterium and exchanged with protium to determine the effectiveness of a batch-wise isotopic exchange process. A total of seven exchange cycles were performed. Gas samples were taken nominally at the beginning, middle, and end of each desorption cycle. Sample analyses showed the isotopic exchange process does not follow the standard dilution model commonly reported. Samples taken at the start of the desorption process were lower in deuterium (the gas to be removed) than those taken later in the desorption cycle. The results are explained in terms of incomplete mixing of the exchange gas in the low pressure hydride.

Klein, J.

2010-12-14T23:59:59.000Z

248

METHOD FOR PRODUCING ISOTOPIC METHANES FROM LITHIUM CARBONATE AND LITHIUM HYDRIDE  

DOE Patents (OSTI)

A process is descrlbed for the production of methane and for the production of methane containing isotopes of hydrogen and/or carbon. Finely divided lithium hydrlde and litldum carbonate reactants are mixed in intimate contact and subsequently compacted under pressures of from 5000 to 60,000 psl. The compacted lithium hydride and lithium carbenate reactunts are dispised in a gas collecting apparatus. Subsequently, the compact is heated to a temperature in the range 350 to 400 deg C whereupon a solid-solid reaction takes place and gaseous methane is evolved. The evolved methane is contaminated with gaseous hydrogen and a very small amount of CO/sub 2/; however, the desired methane product is separated from sald impurities by well known chemical processes, e.g., condensation in a cold trap. The product methane contalns isotopes of carbon and hydrogen, the Isotopic composition being determined by the carbon isotopes originally present In the lithium carbonate and the hydrogen isotopes originally present in the lithium hydride.

Frazer, J.W.

1959-10-27T23:59:59.000Z

249

A Novel Zr-1Nb Alloy and a New Look at Hydriding  

Science Conference Proceedings (OSTI)

A novel Zr-1Nb has begun development based on a working model that takes into account the hydrogen permeabilities for zirconium and niobium metals. The beta-Nb secondary phase particles (SPPs) in Zr-1Nb are believed to promote more rapid hydrogen dynamics in the alloy in comparison to other zirconium alloys. Furthermore, some hydrogen release is expected at the lower temperatures corresponding to outages when the partial pressure of H2 in the coolant is less. These characteristics lessen the negative synergism between corrosion and hydriding that is otherwise observed in cladding alloys without niobium. In accord with the working model, development of nanoscale precursors was initiated to enhance the performance of existing Zr-1Nb alloys. Their characteristics and properties can be compared to oxide-dispersion strengthened alloys, and material additions have been proposed to zirconium-based LWR cladding to guard further against hydriding and to fix the size of the SPPs for microstructure stability enhancements. A preparative route is being investigated that does not require mechanical alloying, and 10 nanometer molybdenum particles have been prepared which are part of the nanoscale precursors. If successful, the approach has implications for long term dry storage of used fuel and for new routes to nanoferritic and ODS alloys.

Robert D. Mariani; James I. Cole; Assel Aitkaliyeva

2013-09-01T23:59:59.000Z

250

ALUMINUM HYDRIDE, A1H3, AS A HYDROGEN STORAGE COMPOUND.  

DOE Green Energy (OSTI)

Aluminum hydride is a covalent, binary hydride that has been known for more than 60 years and is an attractive medium for on-board automotive hydrogen storage, since it contains 10.1% by wt. hydrogen with a density of 1.48 g/ml. There are at least 7 non-solvated AlH{sub 3} phases, namely {alpha}, {alpha}{prime}, {beta}, {gamma}, {var_epsilon} and {zeta}. The properties of {alpha}-AlH{sub 3}, obtained from the Dow Chemical Co. in 1980, have been previously reported. Here we present a description of the thermodynamic and kinetic properties of freshly prepared {alpha}, {beta} and {gamma} phases of AlH{sub 3}. In all cases the decomposition kinetics are appreciable below 100 C and all will meet the DOE 2010 gravimetric and volumetric vehicular system targets (6 wt% H{sub 2} and 0.045 kg/L). However, further research will be required to develop an efficient and economical process to regenerate AlH{sub 3} from the spent Al powder.

GRAETZ, J.; REILLY, J.; SANDROCK, G.; JOHNSON, J.; ZHOU, W.M.; WEGRZYN, J.

2006-11-27T23:59:59.000Z

251

First-Principles Modeling of Hydrogen Storage in Metal Hydride Systems  

SciTech Connect

The objective of this project is to complement experimental efforts of MHoCE partners by using state-of-the-art theory and modeling to study the structure, thermodynamics, and kinetics of hydrogen storage materials. Specific goals include prediction of the heats of formation and other thermodynamic properties of alloys from first principles methods, identification of new alloys that can be tested experimentally, calculation of surface and energetic properties of nanoparticles, and calculation of kinetics involved with hydrogenation and dehydrogenation processes. Discovery of new metal hydrides with enhanced properties compared with existing materials is a critical need for the Metal Hydride Center of Excellence. New materials discovery can be aided by the use of first principles (ab initio) computational modeling in two ways: (1) The properties, including mechanisms, of existing materials can be better elucidated through a combined modeling/experimental approach. (2) The thermodynamic properties of novel materials that have not been made can, in many cases, be quickly screened with ab initio methods. We have used state-of-the-art computational techniques to explore millions of possible reaction conditions consisting of different element spaces, compositions, and temperatures. We have identified potentially promising single- and multi-step reactions that can be explored experimentally.

J. Karl Johnson

2011-05-20T23:59:59.000Z

252

Hydride transfer made easy in the oxidation of alcohols catalyzed by choline oxidase  

Science Conference Proceedings (OSTI)

Choline oxidase (E.C. 1.1.3.17) catalyzes the two-step, four-electron oxidation of choline to glycine betaine with betaine aldehyde as enzyme-associated intermediate and molecular oxygen as final electron acceptor (Scheme 1). The gem-diol, hydrated species of the aldehyde intermediate of the reaction acts as substrate for aldehyde oxidation, suggesting that the enzyme may use similar strategies for the oxidation of the alcohol substrate and aldehyde intermediate. The determination of the chemical mechanism for alcohol oxidation has emerged from biochemical, mechanistic, mutagenetic, and structural studies. As illustrated in the mechanism of Scheme 2, the alcohol substrate is initially activated in the active site of the enzyme by removal of the hydroxyl proton. The resulting alkoxide intermediate is then stabilized in the enzyme-substrate complex via electrostatic interactions with active site amino acid residues. Alcohol oxidation then occurs quantum mechanically via the transfer of the hydride ion from the activated substrate to the N(5) flavin locus. An essential requisite for this mechanism of alcohol oxidation is the high degree of preorganization of the activated enzyme-substrate complex, which is achieved through an internal equilibrium of the Michaelis complex occurring prior to, and independently from, the subsequent hydride transfer reaction. The experimental evidence that support the mechanism for alcohol oxidation shown in Scheme 2 is briefly summarized in the Results and Discussion section.

Gadda, G.; Orville, A.; Pennati, A.; Francis, K.; Quaye, O.; Yuan, H.; Rungsrisuriyachai, K.; Finnegan, S.; Mijatovic, S.; Nguyen, T.

2008-06-08T23:59:59.000Z

253

Mechanical Behavior Studies of Depleted Uranium in the Presence of Hydrides  

DOE Green Energy (OSTI)

This project addresses critical issues related to aging in the presence of hydrides (UH{sub 3}) in DU and the subsequent effect on mechanical behavior. Rolled DU specimens with three different hydrogen concentrations and the as-rolled condition were studied. The texture measurements indicate that the hydrogen charging is affecting the initial as-rolled DU microstructure/texture. The macroscopic mechanical behavior suggests the existence of a threshold between the 0 wpmm H and 0.3 wppm H conditions. A VPSC simulation of the macroscopic strain-stress behavior, when taking into account only a texture effect, shows no agreement with the experiment. This suggests that the macroscopic mechanical behavior observed is indeed due to the presence of hydrogen/hydrides in the DU bulk. From the lattice strain variation it can be concluded that the hydrogen is affecting the magnitude and/or the nature of CRSS. The metallography indicates the specimens that underwent the hydrogen charging process, developed large grains and twinning, which were enhanced by the presence of hydrogen. Further studies using electron microscopy and modeling will be conducted to learn about the deformation mechanisms responsible for the observed behavior.

Garlea, E.; Morrell, J. S.; Bridges, R. L.; Powell, G. L.; Brown, d. W.; Sisneros, T. A.; Tome, C. N.; Vogel, S. C.

2011-02-14T23:59:59.000Z

254

Review of Uranium Hydriding and Dehydriding Rate Models in GOTH_SNF for Spent Fuel MCO Calculations  

DOE Green Energy (OSTI)

The present report is one of a series of three. The series provides an independent technical review of certain aspects of the GOTH_SNF code that is used for accident analysis of the multicanister overpack (MCO) that is proposed for permanent storage of spent nuclear fuel in the planned repository at Yucca Mountain, Nevada. The work documented in the present report and its two companions was done under the auspices of the National Spent Nuclear Fuel Program. The other reports in the series are DOE/SNF/REP-087 and DOE/SNF/REP-088. This report analyzes the model for uranium hydriding and dissociation of the hydride that was documented in the SNF report titled MCO Work Book GOTH_SNF Input Data.1 Reference 1 used a single expression from a model by Bloch and Mintz for both the uranium hydriding and dehydriding reactions. This report compares the results of the GOTH_SNF expression for both phenomena with those from the models proposed by J. B. Condon and further developed by Condon and J. R. Kirkpatrick. The expression for the uranium hydriding rate used in GOTH_SNF (from the model of Bloch and Mintz) gives consistently lower values than those from the models of Condon and Kirkpatrick. This is true for all hydrogen pressures and for all temperatures. For a hydrogen pressure of 1 atm, the hydriding rates given by the models of Condon and Kirkpatrick are zero by the time the temperature reaches 400C. That is, the term representing the dehydriding reaction has become large enough to overwhelm the term representing the hydriding reaction. The same is true for the expression used in GOTH_SNF. For lower hydrogen pressures, the hydriding rates reach zero at even lower temperatures for the Bloch and Mintz model and also for the Condon and Kirkpatrick models. Uranium dehydriding rates can be calculated for temperatures as high as 2,000C. The dehydriding rates from GOTH_SNF contain an assumption that there is a 0.22 psia hydrogen pressure in the atmosphere surrounding the hydride. For temperatures >~700C, the expression from GOTH_SNF (the model of Bloch and Mintz) gives higher dehydriding rates than that from Condon. However, in calculations of MCOs using GOTH_SNF, the dehydriding is complete by ~400C so that rates for temperatures higher than that are not relevant. In the temperature range 275400C, the dehydriding rate from the Condon model is much higher than that from GOTH_SNF. The practical consequences of the differences in hydriding and dehydriding rates are not obvious. A way to evaluate the consequences is to repeat an important MCO calculation on GOTH_SNF using hydriding and dehydriding rates that have been artificially modified to be closer to those given by the expressions of Condon and Kirkpatrick and see if the conclusions about the safety of the MCO are changed.

John R. Kirkpatrick; Chris A. Dahl

2003-09-01T23:59:59.000Z

255

Method and apparatus for atomic imaging  

SciTech Connect

A method and apparatus for three dimensional imaging of the atomic environment of disordered adsorbate atoms are disclosed. The method includes detecting and measuring the intensity of a diffuse low energy electron diffraction pattern formed by directing a beam of low energy electrons against the surface of a crystal. Data corresponding to reconstructed amplitudes of a wave form is generated by operating on the intensity data. The data corresponding to the reconstructed amplitudes is capable of being displayed as a three dimensional image of an adsorbate atom. The apparatus includes a source of a beam of low energy electrons and a detector for detecting the intensity distribution of a DLEED pattern formed at the detector when the beam of low energy electrons is directed onto the surface of a crystal. A device responsive to the intensity distribution generates a signal corresponding to the distribution which represents a reconstructed amplitude of a wave form and is capable of being converted into a three dimensional image of the atomic environment of an adsorbate atom on the crystal surface.

Saldin, Dilano K. (Milwaukee, WI); de Andres Rodriquez, Pedro L. (Madrid, ES)

1993-01-01T23:59:59.000Z

256

Materials' Deformation Dynamics at Atomic Scale In situ Atomic ...  

Science Conference Proceedings (OSTI)

Presentation Title, Materials' Deformation Dynamics at Atomic Scale In situ Atomic .... What Can We Learn from Measurements of Li-ion Battery Single Particles?

257

general_atomics.cdr  

NLE Websites -- All DOE Office Websites (Extended Search)

former former General Atomics Hot Cell Facility was constructed in 1959 and operated until 1991. The site encompassed approximately 7,400 square feet of laboratory and remote operations cells. Licensed operations at the facility included receipt, handling, and shipment of radioactive materials; remote handling, examination, and storage of previously irradiated nuclear fuel materials; pilot-scale tritium extraction operations; and development, fabrication, and inspection of uranium oxide-beryllium oxide fuel materials. General Atomics performed most of the work for the federal government. The General Atomics Hot Cell Facility was located in a 60-acre complex 13 miles northwest of downtown San Diego, 1 mile inland from the Pacific Ocean, and approximately 300 feet above sea level. The General Atomics site is in the center of Torrey Mesa Science Center, a 304-acre industrial

258

general_atomics.cdr  

Office of Legacy Management (LM)

from the U.S. Department of Energy (DOE). Discussions between DOE and General Atomics led to an agreed cost-sharing and no-fee arrangement for the decontamination and site...

259

Development of Regenerable High Capacity Boron Nitrogen Hydrides as Hydrogen Storage Materials  

DOE Green Energy (OSTI)

The objective of this three-phase project is to develop synthesis and hydrogen extraction processes for nitrogen/boron hydride compounds that will permit exploitation of the high hydrogen content of these materials. The primary compound of interest in this project is ammonia-borane (NH{sub 3}BH{sub 3}), a white solid, stable at ambient conditions, containing 19.6% of its weight as hydrogen. With a low-pressure on-board storage and an efficient heating system to release hydrogen, ammonia-borane has a potential to meet DOE's year 2015 specific energy and energy density targets. If the ammonia-borane synthesis process could use the ammonia-borane decomposition products as the starting raw material, an efficient recycle loop could be set up for converting the decomposition products back into the starting boron-nitrogen hydride. This project is addressing two key challenges facing the exploitation of the boron/nitrogen hydrides (ammonia-borane), as hydrogen storage material: (1) Development of a simple, efficient, and controllable system for extracting most of the available hydrogen, realizing the high hydrogen density on a system weight/volume basis, and (2) Development of a large-capacity, inexpensive, ammonia-borane regeneration process starting from its decomposition products (BNHx) for recycle. During Phase I of the program both catalytic and non-catalytic decomposition of ammonia borane are being investigated to determine optimum decomposition conditions in terms of temperature for decomposition, rate of hydrogen release, purity of hydrogen produced, thermal efficiency of decomposition, and regenerability of the decomposition products. The non-catalytic studies provide a base-line performance to evaluate catalytic decomposition. Utilization of solid phase catalysts mixed with ammonia-borane was explored for its potential to lower the decomposition temperature, to increase the rate of hydrogen release at a given temperature, to lead to decomposition products amenable for regeneration, and direct catalytic hydrogenation of the decomposition products. Two different approaches of heating ammonia-borane are being investigated: (a) 'heat to material approach' in which a fixed compartmentalized ammonia-borane is heated by a carefully controlled heating pattern, and (b) 'material to heat approach' in which a small amount of ammonia-borane is dispensed at a time in a fixed hot zone. All stages of AB decomposition are exothermic which should allow the small 'hot zone' used in the second approach for heating to be self-sustaining. During the past year hydrogen release efforts focused on the second approach determining the amount of hydrogen released, kinetics of hydrogen release, and the amounts of impurities released as a function of AB decomposition temperature in the 'hot zone.'

Damle, A.

2010-02-03T23:59:59.000Z

260

Sharing the atom bomb  

Science Conference Proceedings (OSTI)

Shaken by the devastation of Hiroshima and Nagasaki and fearful that the American atomic monopoly would spark an arms race, Dean Acheson led a push in 1946 to place the bomb-indeed, all atomic energy-under international control. But as the memories of wartime collaboration faded, relations between the superpowers grew increasingly tense, and the confrontational atmosphere undid his proposal. Had Acheson succeeded, the Cold War might not have been. 2 figs.

Chace, J.

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Metal atomization spray nozzle  

DOE Patents (OSTI)

A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal.

Huxford, Theodore J. (Harriman, TN)

1993-01-01T23:59:59.000Z

262

Metal atomization spray nozzle  

DOE Patents (OSTI)

A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal. 6 figures.

Huxford, T.J.

1993-11-16T23:59:59.000Z

263

Effects of atomic radiation  

SciTech Connect

This book focuses on the lifelong effects of atomic radiation exposure in language understandable by the concerned layperson or the specialist in another field. The base of knowledge used is the work of the Atomic Bomb Casualty Commission and its successor since 1975 the Radiation Effects Research Foundation. Within the range of Chronic effects on human health the book provides a thorough review, although effects of nonionizing radiation, effects on structures, effects on other living species, and acute effects are not discussed.

Schull, W.J.

1995-12-31T23:59:59.000Z

264

Atomizing nozzle and method  

DOE Patents (OSTI)

A high pressure close-coupled gas atomizing nozzle includes multiple discrete gas jet discharge orifices having aerodynamically designed convergent-divergent geometry with an first converging section communicated to a gas supply manifold and to a diverging section by a constricted throat section to increase atomizing gas velocity. The gas jet orifices are oriented at gas jet apex angle selected relative to the melt supply tip apex angle to establish a melt aspiration condition at the melt supply tip.

Ting, Jason (Ames, IA); Anderson, Iver E. (Ames, IA); Terpstra, Robert L. (Ames, IA)

2000-03-16T23:59:59.000Z

265

Atomic Data for Americium (Am)  

Science Conference Proceedings (OSTI)

... Atomic Number = 95. Atomic Weight = (243). Reference E95. Isotope, Mass, Abundance, Spin, Mag Moment, 241 Am, 241.056823, 0, 5/2, +1.61. ...

266

Thermo-fluid Dynamics of Flash Atomizing Sprays and Single Droplet Impacts.  

E-Print Network (OSTI)

??Spray atomization and droplet dynamics are research topics that have existed for many decades. Their prevalence in manufacturing, energy generation and other practical applications is (more)

Vu, Henry

2010-01-01T23:59:59.000Z

267

Raman Spectroscopy of Lithium Hydride Corrosion: Selection of an Appropriate Excitation Wavelength to Minimize Fluorescence  

DOE Green Energy (OSTI)

The recent interest in a hydrogen-based fuel economy has renewed research into metal hydride chemistry. Many of these compounds react readily with water to release hydrogen gas and form a caustic. Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFT) has been used to study the hydrolysis reaction. The LiOH stretch appears at 3670 cm{sup -1}. Raman spectroscopy is a complementary technique that employs monochromatic excitation (laser) allowing access to the low energy region of the vibrational spectrum (<600 cm{sup -1}). Weak scattering and fluorescence typically prevent Raman from being used for many compounds. The role of Li{sub 2}O in the moisture reaction has not been fully studied for LiH. Li{sub 2}O can be observed by Raman while being hidden in the Infrared spectrum.

Stowe, A. C.; Smyrl, N. R.

2011-05-26T23:59:59.000Z

268

Development of encapsulated lithium hydride sink-side thermal energy storage for pulsed space power systems  

DOE Green Energy (OSTI)

Value analysis indicates that inclusion of thermal energy storage (TES) as an element in a pulsed space power supply will reduce the mass of the heat rejection system. A candidate design for the TES component utilizes lithium hydride (LiH) encapsulated in 304L stainless steel or molybdenum in a packed-bed configuration with a lithium or sodium-potassium (NaK) heat transport fluid. Critical concerns with this concept are the need to (1) accommodate shell stresses induced by volumetric expansion of the melting salt or surface gripping by the freezing salt and (2) minimize hydrogen loss through the shell due to LiH dissociation at high temperatures. Experimental observation of significant cracking of the LiH during cooling mitigates the first of these issues by providing a leakage path into the interior void as melting occurs at the salt-containment interface, thus allowing use of thin shells.

Morris, D.G.; Foote, J.P.; Olszewski, M.; Whittaker, J.W.

1988-01-01T23:59:59.000Z

269

LaNi{sub 5}-based metal hydride electrode in Ni-MH rechargeable cells  

DOE Patents (OSTI)

An at least ternary metal alloy of the formula AB{sub (Z-Y)}X{sub (Y)} is disclosed. In this formula, A is selected from the rare earth elements, B is selected from the elements of Groups 8, 9, and 10 of the Periodic Table of the Elements, and X includes at least one of the following: antimony, arsenic, germanium, tin or bismuth. Z is greater than or equal to 4.8 and less than or equal to 6.0. Y is greater than 0 and less than 1. Ternary or higher-order substitutions to the base AB{sub 5} alloys that form strong kinetic interactions with the predominant metals in the base metal hydride are used to form metal alloys with high structural integrity after multiple cycles of hydrogen sorption. 16 figs.

Bugga, R.V.; Fultz, B.; Bowman, R.; Surampudi, S.R.; Witham, C.K.; Hightower, A.

1999-03-30T23:59:59.000Z

270

Development of a lithium hydride powered hydrogen generator for use in long life, low power PEM fuel cell power supplies  

E-Print Network (OSTI)

This thesis studies a hybrid PEM fuel cell system for use in low power, long life sensor networks. PEM fuel cells offer high efficiency and environmental friendliness but have not been widely adopted due to cost, reliability, ...

Strawser, Daniel DeWitt

2012-01-01T23:59:59.000Z

271

Zinc-Column Hydride Generation and 7'rapping Dilute standards or samples containing less than 5 mg  

E-Print Network (OSTI)

- sium iodide-iodine trapping solution in the centrifuge tube. The nitrogen gas flow rate wasadjusted furnace program (Table I). Gas flow was stopped during the atomizationstep. TABLE I Optimized Furnace

Canberra, University of

272

Questions and Answers - How do atoms form?  

NLE Websites -- All DOE Office Websites (Extended Search)

(Biggest and smallest atom?) Questions and Answers Main Index Next Question (Does gravity affect atoms?) Does gravity affect atoms? How do atoms form? The current view is that...

273

Questions and Answers - Can you crush atoms?  

NLE Websites -- All DOE Office Websites (Extended Search)

Does gravity affect atoms? Previous Question (Does gravity affect atoms?) Questions and Answers Main Index Next Question (Parts and weights of atoms?) Parts and weights of atoms?...

274

Changes related to "Zhejiang Windey Wind Generating Engineering...  

Open Energy Info (EERE)

"http:en.openei.orgwikiSpecial:RecentChangesLinkedZhejiangWindeyWindGeneratingEngineering" Atom Special pages About us Disclaimers Energy blogs Developer services...

275

Peaceful Uses of the Atom and Atoms for Peace  

Office of Scientific and Technical Information (OSTI)

Peaceful Uses of the Atom Peaceful Uses of the Atom Fermi and Atoms for Peace · Understanding the Atom · Seaborg · Teller Atoms for Peace Atoms for Peace + 50 - Conference, October 22, 2003 Celebrating the 50th anniversary of President Eisenhower's "Atoms for Peace" speech to the UN General Assembly Atoms for Peace (video 12:00 Minutes) Atoms for Peace Address given by Dwight D. Eisenhower before the General Assembly of the United Nations, New York City, December 8, 1953 Documents: Atomic Power in Space: A History A history of the Space Isotope Power Program of the United States from the mid-1950s through 1982; interplanetary space exploration successes and achievements have been made possible by this technology. Establishing Site X: Letter, Arthur H. Compton to Enrico Fermi, September 14, 1942

276

Strongly driven one-atom laser and decoherence monitoring  

Science Conference Proceedings (OSTI)

We propose the implementation of a strongly driven one-atom laser, based on the off-resonant interaction of a three-level atom in {lambda} configuration with a single cavity mode and three laser fields. We show that the system can be described equivalently by a two-level atom resonantly coupled to the cavity and driven by a strong effective coherent field. The effective dynamics can be solved exactly, including a thermal field bath, allowing an analytical description of field statistics and entanglement properties. We also show the possible generation of quantum superposition (Schroedinger cat) states for the whole atom-field system and for the field alone after atomic measurement. We propose a way to monitor the system decoherence by measuring atomic populations. Finally, we confirm the validity of our model through numerical solutions.

Lougovski, P. [Hearne Institute for Theoretical Physics, Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803 (United States); Casagrande, F.; Lulli, A. [Dipartimento di Fisica, Universita di Milano, Via Celoria 16, 20133 Milan (Italy); Solano, E. [Physics Department, ASC, and CeNS, Ludwig-Maximilians-Universitaet, Theresienstrasse 37, 80333 Munich (Germany); Seccion Fisica, Departamento de Ciencias, Pontificia Universidad Catolica del Peru, Apartado 1761, Lima (Peru)

2007-09-15T23:59:59.000Z

277

Strongly-Driven One-Atom Laser and Decoherence Monitoring  

E-Print Network (OSTI)

We propose the implementation of a strongly-driven one-atom laser, based on the off-resonant interaction of a three-level atom in $\\Lambda$-configuration with a single cavity mode and three laser fields. We show that the system can be described equivalently by a two-level atom resonantly coupled to the cavity and driven by a strong effective coherent field. The effective dynamics can be solved exactly, including a thermal field bath, allowing an analytical description of field statistics and entanglement properties. We also show the possible generation of Schr\\"odinger cat states for the whole atom-field system and for the field alone after atomic measurement. We propose a way to monitor the system decoherence by measuring atomic population. Finally, we confirm the validity of our model through numerical solutions.

P. Lougovski; F. Casagrande; A. Lulli; E. Solano

2007-02-06T23:59:59.000Z

278

Hydrogen storage via metal hydrides for utility and automotive energy storage applications. [HCl electrolysis for H/sub 2/--Cl/sub 2/ fuel cells  

DOE Green Energy (OSTI)

Brookhaven National Laboratory is currently supported by ERDA to develop the technology and techniques for storing hydrogen via metal hydrides. Hydrogen is able to react with a wide variety of metal and metal alloy materials to form hydride compounds of hydrogen and metals. These compounds differ in stability--some are relatively unstable and can be readily formed and decomposed at low temperatures. The use of these systems for hydrogen storage involves the design of heat exchanger and mass transfer systems, i.e., removal of heat during the charging reaction and addition of heat during the discharge reaction. The most notable example of a metal hydride material is iron titanium which shows promise of being economical for a number of near term hydrogen storage applications. Recent work and progress on the development of metal hydrides for hydrogen storage connected with utility energy storage applications and natural gas supplementation are discussed and electric-to-electric storage system is described in some detail. A system of energy storage involving the electrolysis of hydrochloric acid is described which would utilize metal hydrides to store the hydrogen. In addition, the use of metal hydrides for hydrogen storage in automotive systems is described.

Salzano, F J; Braun, C; Beaufrere, A; Srinivasan, S; Strickland, G; Reilly, J J; Waide, C

1976-08-01T23:59:59.000Z

279

NIST Atomic Spectroscopy Data Center  

Science Conference Proceedings (OSTI)

Atomic Spectroscopy Data Center. ... Responds to user requests for data, literature references, and technical information. ...

2011-11-29T23:59:59.000Z

280

Lesson 3- Atoms and Isotopes  

Energy.gov (U.S. Department of Energy (DOE))

Youve probably heard people refer to nuclear energy as atomic energy. Why? Nuclear energy is the energy that is stored in the bonds of atoms, inside the nucleus. Nuclear power plants are designed to capture this energy as heat and convert it to electricity. This lesson looks closely at what atoms are and how atoms store energy.

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

general_atomics.cdr  

Office of Legacy Management (LM)

former General former General Atomics Hot Cell Facility was constructed in 1959 and operated until 1991. The site encompassed approximately 7,400 square feet of laboratory and remote operations cells. Licensed operations at the facility included receipt, handling, and shipment of radioactive materials; remote handling, examination, and storage of previously irradiated nuclear fuel materials; pilot-scale tritium extraction operations; and development, fabrication, and inspection of uranium oxide-beryllium oxide fuel materials. General Atomics performed most of the work for the federal government. The General Atomics Hot Cell Facility was located in a 60-acre complex 13 miles northwest of downtown San Diego, 1 mile inland from the Pacific Ocean, and approximately 300 feet above sea level.

282

Distributed Generation  

NLE Websites -- All DOE Office Websites (Extended Search)

Untapped Value of Backup Generation Untapped Value of Backup Generation While new guidelines and regulations such as IEEE (Institute of Electrical and Electronics Engineers) 1547 have come a long way in addressing interconnection standards for distributed generation, utilities have largely overlooked the untapped potential of these resources. Under certain conditions, these units (primarily backup generators) represent a significant source of power that can deliver utility services at lower costs than traditional centralized solutions. These backup generators exist today in large numbers and provide utilities with another option to reduce peak load, relieve transmission congestion, and improve power reliability. Backup generation is widely deployed across the United States. Carnegie Mellon's Electricity

283

Materials Go/No-Go Decisions Made Within the Department of Energy Metal Hydride Center of Excellence  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Go/No-Go Decisions Made Within Materials Go/No-Go Decisions Made Within the Department of Energy Metal Hydride Center of Excellence (MHCoE) In fulfillment of the end of Fiscal Year 2007 Project Milestone on Materials Down-selection Lennie Klebanoff, Director Sandia National Laboratories Livermore, CA 94551 September/October 2007 1 Acknowledgements The author wishes to acknowledge the contributions of all Principal Investigators within the Metal Hydride Center of Excellence (MHCoE) to the work summarized herein. Their names and affiliations are listed below. Especially significant contributions to this document were made by Dr. Ewa Ronnebro (SNL), Dr. John Vajo (HRL), Prof. Zak Fang (U. Utah), Dr. Robert Bowman Jr. (JPL), Prof. David Sholl (CMU) and Prof. Craig Jensen (U. Hawaii). The author thanks Dr.

284

URANIUM METAL POWDER PRODUCTION, PARTICLE DISTRIBUTION ANALYSIS, AND REACTION RATE STUDIES OF A HYDRIDE-DEHYDRIDE PROCESS  

E-Print Network (OSTI)

Work was done to study a hydride-dehydride method for producing uranium metal powder. Particle distribution analysis was conducted using digital microscopy and grayscale image analysis software. The particle size was found to be predominantly in the 40 ?m range, which agreed with previous work. The effects of temperature, pressure, and time on the reaction fraction of powder were measured by taking experimental data. The optimum hydride temperature for the system was found to be 233.4C. Higher gas pressures resulted in higher reaction fractions, over the range studied. For the sample parameters studied, a time of 371 minutes was calculated to achieve complete powderization. System design parameters for commercialization are proposed.

Sames, William

2011-05-01T23:59:59.000Z

285

Erroneous Wave Functions of Ciuchi et al for Collective Modes in Neutron Production on Metallic Hydride Cathodes  

E-Print Network (OSTI)

There is a recent comment (Ciuchi et al., 2012) concerning the theory of collective many body effects on the neutron production rates in a chemical battery cathode. Ciuchi et al employ an inverse beta decay expression that contains a two body amplitude. Only one electron and one proton may exist in the Ciuchi et al model initial state wave function. A flaw in their reasoning is that one cannot in reality describe collective many body correlations with only a two particle wave function. One needs very many particles to describe collective effects. In the model wave functions of Ciuchi et al there are no metallic hydrides, there are no cathodes and there are no chemical batteries. Employing a wave function with only one electron and one proton is inadequate for describing collective metallic hydride surface quantum plasma physics in cathodes accurately.

A. Widom; Y. N. Srivastava; L. Larsen

2012-10-17T23:59:59.000Z

286

Layered Atom Arrangements in Complex Materials  

Science Conference Proceedings (OSTI)

In this report, we develop an atom layer stacking model to describe systematically the crystal structures of complex materials. To illustrate the concepts, we consider a sequence of oxide compounds in which the metal cations progress in oxidation state from monovalent (M{sup 1+}) to tetravalent (M{sup 4+}). We use concepts relating to geometric subdivisions of a triangular atom net to describe the layered atom patterns in these compounds (concepts originally proposed by Shuichi Iida). We demonstrate that as a function of increasing oxidation state (from M{sup 1+} to M{sup 4+}), the layer stacking motifs used to generate each successive structure (specifically, motifs along a 3 symmetry axis), progress through the following sequence: MMO, MO, M{sub r}O, MO{sub r/s}O{sub u/v}, MOO (where M and O represent fully dense triangular atom nets and r/s and u/v are fractions used to describe partially filled triangular atom nets). We also develop complete crystallographic descriptions for the compounds in our oxidation sequence using trigonal space group R{bar 3}.

K.E. Sikafus; R.W.Grimes; S.M.Corish; A.R. Cleave; M.Tang; C.R.Stanek; B.P. Uberuaga; J.A.Valdez

2005-04-15T23:59:59.000Z

287

JILA Researchers Discover Atomic Clock Can Simulate ...  

Science Conference Proceedings (OSTI)

... Artist's conception of interactions among atoms in JILA's strontium atomic clock during a quantum simulation experiment. ...

2013-08-20T23:59:59.000Z

288

Atom-probe field-ion-microscopy study of Fe-Ti alloys  

DOE Green Energy (OSTI)

A newly developed high-performance atom-probe (field ion microscope) was employed for the composition analysis of Fe-Ti alloys and their interactions with ambient gas, such as H/sub 2/ and O/sub 2/. With a mass resolution (m/..delta..m) better than 2000 and a spatial resolution of a few A, all isotopes of Fe and Ti and their hydrides and other compounds are clearly resolved during the depth profile study. Some of our findings are: (1) Titanium segregated on the surface and grain boundaries upon heating (greater than or equal to 900/sup 0/C), in the form of oxides, and (2) some Ti in the bulk forms clusters of various sizes with C, O, and/or N as nuclei.

Pickering, H.W.; Kuk, Y.; Sakurai, T.

1980-01-01T23:59:59.000Z

289

All-optical ion generation for ion trap loading  

E-Print Network (OSTI)

We have investigated the all-optical generation of ions by photo-ionisation of atoms generated by pulsed laser ablation. A direct comparison between a resistively heated oven source and pulsed laser ablation is reported. Pulsed laser ablation with 10 ns Nd:YAG laser pulses is shown to produce large calcium flux, corresponding to atomic beams produced with oven temperatures greater than 650 K. For an equivalent atomic flux, pulsed laser ablation is shown to produce a thermal load more than one order of magnitude smaller than the oven source. The atomic beam distributions obey Maxwell-Boltzmann statistics with most probable speeds corresponding to temperatures greater than 2200 K. Below a threshold pulse fluence between 280 mJ/cm^2 and 330 mJ/cm^2, the atomic beam is composed exclusively of ground state atoms. For higher fluences ions and excited atoms are generated.

Sheridan, Kevin; Keller, Matthias

2011-01-01T23:59:59.000Z

290

Tomography of a High-Purity Narrowband Photon From a Transient Atomic Collective Excitation  

E-Print Network (OSTI)

We demonstrate the efficient heralded generation of high purity narrow-bandwidth single photons from a transient collective spin excitation in a hot atomic vapour cell. Employing optical homodyne tomography, we fully reconstruct the density matrix of the generated photon and observe a Wigner function reaching the zero value without correcting for any inefficiencies. The narrow bandwidth of the photon produced is accompanied by a high generation rate yielding a high spectral brightness. The source is therefore compatible with atomic-based quantum memories as well as other applications in light-atom interfacing. This work paves the way to preparing and measuring arbitrary superposition states of collective atomic excitations.

MacRae, A; Lvovsky, A I

2011-01-01T23:59:59.000Z

291

Request for Support for the Conference on Super Intense Laser Atom Physics  

Science Conference Proceedings (OSTI)

The Conference on Super Intense Laser Atom Physics (SILAP) was held in November 2003 in Dallas, Texas. The venue for the meeting was South Fork Ranch in the outskirts of Dallas. The topics of the meeting included high harmonic generation and attosecond pulse generation, strong field interactions with molecules and clusters, particle acceleration, and relativistic laser atom interactions.

Todd Ditmire

2004-10-21T23:59:59.000Z

292

Ytterbium Gains Ground in Quest for Next-Generation Atomic ...  

Science Conference Proceedings (OSTI)

... (Because the international definition of the ... A laser that ticks 518 trillion times per second induces a transition between two energy levels in the ...

2010-12-29T23:59:59.000Z

293

Tenth Atomic Physics Program workshop  

Science Conference Proceedings (OSTI)

This report contains short papers and abstracts on the following main topics: Ion-atom collision theory; laser physics; spectroscopy of atoms; spectroscopy of ions; and high velocity collisions.

Not Available

1989-10-01T23:59:59.000Z

294

Nuclear effects in atomic transitions  

E-Print Network (OSTI)

Atomic electrons are sensitive to the properties of the nucleus they are bound to, such as nuclear mass, charge distribution, spin, magnetization distribution, or even excited level scheme. These nuclear parameters are reflected in the atomic transition energies. A very precise determination of atomic spectra may thus reveal information about the nucleus, otherwise hardly accessible via nuclear physics experiments. This work reviews theoretical and experimental aspects of the nuclear effects that can be identified in atomic structure data. An introduction to the theory of isotope shifts and hyperfine splitting of atomic spectra is given, together with an overview of the typical experimental techniques used in high-precision atomic spectroscopy. More exotic effects at the borderline between atomic and nuclear physics, such as parity violation in atomic transitions due to the weak interaction, or nuclear polarization and nuclear excitation by electron capture, are also addressed.

Plffy, Adriana

2011-01-01T23:59:59.000Z

295

Tritium generation and neutron measurements in Pd-Si under high deuterium gas pressure  

SciTech Connect

This paper summarizes some of the methods applicable for low level tritium detection needed in the search for anomalous fusion in metal hydrides. It is also intended to further detail our tritium and neutron results that have been obtained with the Pd-Si-D system, originally presented at earlier workshops. A measure of reproducibility that was not evident in our previous work has been achieved partially due to the better detection sensitivity afforded by the use of low tritium deuterium and partially from the fact that the foil-wafer cells can be made with nearly identical electrical characteristics. This reproducibility has allowed us to narrow the optimum conditions for the experiment. While this experiment is rather different from the standard'' electrolytic cell or the Ti gas hydride experiment, similarities exist in that non equilibrium conditions are sought and the tritium generation levels are low and neutron emission is extremely weak. In contrast to many electrochemical cell experiments, the system used in these experiments is completely sealed during operation and uses no electrolyte. The major improvements to the experiment have been the use of vary low tritium deuterium for the hydriding and the replacement of the aluminum neutron counter tubes with ones of stainless steel. These changes have resulted in pronounced improvements to the detection systems since the background tritium level in the gas has been reduced by a factor of 300 and the neutron background has been decreased by a factor of 14. 16 refs., 8 figs., 1 tab.

Claytor, T.N.; Tuggle, D.G.; Menlove, H.O.

1991-01-01T23:59:59.000Z

296

Characteristics of the high-rate discharge capability of a nickel/metal hydride battery electrode  

Science Conference Proceedings (OSTI)

The high rate discharge capability of the negative electrode in a Ni/MH battery is mainly determined by the charge transfer process at the interface between the metal hydride (MH) alloy powder and the electrolyte, and the mass transfer process in the bulk MH alloy powder. In this study, the anodic polarization curves of a MH electrode were measured and analyzed. An alloy of nominal composition Mm{sub 0.95}Ti{sub 0.05}Ni{sub 3.85}Co{sub 0.45}Mn{sub 0.35}Al{sub 0.35} was used as the negative electrode material. With increasing number of charge/discharge cycles, the MH alloy powders microcrack into particles several micrometers in diameter. The decrease in the MH alloy particle size results in an increase in both the activation surface area and the exchange current density of the MH alloy electrode. The electrode overpotentials of the MH electrode decreases with increasing number of cycles at a large value of anodic polarization current. The decrease in electrode overpotential leads to an increase in the high rate discharge capability of the MH electrode. By using the limiting current, the hydrogen diffusion coefficient in the MH alloy was estimated to be 1.2 x 10{sup {minus}11}cm{sup 2}s{sup {minus}1} assuming an average particle radius of 5 {micro}m.

Geng, M.; Han, J.; Feng, F.; Northwood, D.O.

1999-10-01T23:59:59.000Z

297

OXIDATION, HYDRIDING, AND AQUEOUS CORROSION OF U$sub 3$Si ALLOYS.  

DOE Green Energy (OSTI)

Specimens of U{sub 3}Si were heated in air and in hydrogen at temperatures up to 550 degC and the products of reaction studied. The phases observed in these tests are compared with those which form in U{sub 3}Si samples corroded in high temperature water. The aqueous corrosion of U{sub 3}Si is mainly an oxidation reaction although limited hydriding may also occur as a secondary reaction. The oxidation of U{sub 3}Si either in air or water appears to be a multi-step process in which most of the phases of the uranium-silicon system form. Due to the kinetics of formation and stability of the phases at various temperatures all are not observed in an individual test. Although molecular hydrogen will not react with U{sub 3)Si directly, in some cases it will react with free uranium to form UH{sub 3}. If the UH{sub 3} is subsequently oxidized, nascent hydrogen will be released which will react with the U{sub 3}Si.

Feraday, M.A.

1971-11-15T23:59:59.000Z

298

Composition and cycle life of multicomponent AB{sub 5} hydride electrodes  

DOE Green Energy (OSTI)

Multicomponent AB{sub 5} hydrides are attractive replacements for the cadmium electrode in nickel -- cadmium batteries. The archetype compound of the AB{sub 5} alloy class is LaNi{sub 5}, but in a typical battery electrode mischmetal is substituted for La and Ni is substituted in part by variety of metals. While the effects of Ni substitution have been widely studied, relatively little effort has focused on the effect of La substitution. This paper deals with the effect on cycle life due to the increasing presence of Ce in the alloy series La{sub 1-x}Ce{sub x}Ni{sub 3.55}Co{sub .75}Mn{sub .4}Al{sub .3}. Alloys were characterized by the determination of pressure-composition relationships, molar volume of H and electrode cycle life. The effects due to lattice expansion are taken into account. It was concluded that the rate of loss of electrochemical capacity per charge/discharge cycle was significantly decreased due to the presence of Ce.

Adzic, G.D.; Johnson, J.R.; Reilly, J.J.; McBreen, J.; Mukerjee, S. [Brookhaven National Lab., Upton, NY (United States); Kumar, M.P.S.; Zhang, W.; Srinivasan, S. [Texas A and M Univ., College Station, TX (United States). Center for Electrochemical Systems and Hydrogen Research

1994-11-01T23:59:59.000Z

299

Methodology of Materials Discovery in Complex Metal Hydrides Using Experimental and Computational Tools  

Science Conference Proceedings (OSTI)

We present a review of the experimental and theoretical methods used in the discovery of new metal-hydrogen materials systems for hydrogen storage applications. Rather than a comprehensive review of all new materials and methods used in the metal hydride community, we focus on a specific subset of successful methods utilizing theoretical crystal structure prediction methods, computational approaches for screening large numbers of compound classes, and medium-throughput experimental methods for the preparation of such materials. Monte Carlo techniques paired with a simplified empirical Hamiltonian provide crystal structure candidates that are refined using Density Functional Theory. First-principle methods using high-quality structural candidates are further screened for an estimate of reaction energetics, decomposition enthalpies, and determination of reaction pathways. Experimental synthesis utilizes a compacted-pellet sintering technique under high-pressure hydrogen at elevated temperatures. Crystal structure determination follows from a combination of Rietveld refinements of diffraction patterns and first-principles computation of total energies and dynamical stability of competing structures. The methods presented within are general and applicable to a wide class of materials for energy storage.

Majzoub, Eric H.; Ronnebro, Ewa

2012-02-22T23:59:59.000Z

300

Systems Modeling of Chemical Hydride Hydrogen Storage Materials for Fuel Cell Applications  

Science Conference Proceedings (OSTI)

A fixed bed reactor was designed, modeled and simulated for hydrogen storage on-board the vehicle for PEM fuel cell applications. Ammonia Borane (AB) was selected by DOE's Hydrogen Storage Engineering Center of Excellence (HSECoE) as the initial chemical hydride of study because of its high hydrogen storage capacity (up to {approx}16% by weight for the release of {approx}2.5 molar equivalents of hydrogen gas) and its stability under typical ambient conditions. The design evaluated consisted of a tank with 8 thermally isolated sections in which H2 flows freely between sections to provide ballast. Heating elements are used to initiate reactions in each section when pressure drops below a specified level in the tank. Reactor models in Excel and COMSOL were developed to demonstrate the proof-of-concept, which was then used to develop systems models in Matlab/Simulink. Experiments and drive cycle simulations showed that the storage system meets thirteen 2010 DOE targets in entirety and the remaining four at greater than 60% of the target.

Brooks, Kriston P.; Devarakonda, Maruthi N.; Rassat, Scot D.; Holladay, Jamelyn D.

2011-10-05T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Discovery of Novel Complex Metal Hydrides for Hydrogen Storage through Molecular Modeling and Combinatorial Methods  

Science Conference Proceedings (OSTI)

UOP LLC, a Honeywell Company, Ford Motor Company, and Striatus, Inc., collaborated with Professor Craig Jensen of the University of Hawaii and Professor Vidvuds Ozolins of University of California, Los Angeles on a multi-year cost-shared program to discover novel complex metal hydrides for hydrogen storage. This innovative program combined sophisticated molecular modeling with high throughput combinatorial experiments to maximize the probability of identifying commercially relevant, economical hydrogen storage materials with broad application. A set of tools was developed to pursue the medium throughput (MT) and high throughput (HT) combinatorial exploratory investigation of novel complex metal hydrides for hydrogen storage. The assay programs consisted of monitoring hydrogen evolution as a function of temperature. This project also incorporated theoretical methods to help select candidate materials families for testing. The Virtual High Throughput Screening served as a virtual laboratory, calculating structures and their properties. First Principles calculations were applied to various systems to examine hydrogen storage reaction pathways and the associated thermodynamics. The experimental program began with the validation of the MT assay tool with NaAlH4/0.02 mole Ti, the state of the art hydrogen storage system given by decomposition of sodium alanate to sodium hydride, aluminum metal, and hydrogen. Once certified, a combinatorial 21-point study of the NaAlH4 ?? LiAlH4 ??Mg(AlH4)2 phase diagram was investigated with the MT assay. Stability proved to be a problem as many of the materials decomposed during synthesis, altering the expected assay results. This resulted in repeating the entire experiment with a mild milling approach, which only temporarily increased capacity. NaAlH4 was the best performer in both studies and no new mixed alanates were observed, a result consistent with the VHTS. Powder XRD suggested that the reverse reaction, the regeneration of the alanate from alkali hydride, Al and hydrogen, was hampering reversibility. The reverse reaction was then studied for the same phase diagram, starting with LiH, NaH, and MgH2, and Al. The study was extended to phase diagrams including KH and CaH2 as well. The observed hydrogen storage capacity in the Al hexahydrides was less than 4 wt. %, well short of DOE targets. The HT assay came on line and after certification with studies on NaAlH4, was first applied to the LiNH2 - LiBH4 - MgH2 phase diagram. The 60-point study elucidated trends within the system locating an optimum material of 0.6 LiNH2 ?? 0.3 MgH2 ?? 0.1 LiBH4 that stored about 4 wt. % H2 reversibly and operated below 220 °C. Also present was the phase Li4(NH2)3BH4, which had been discovered in the LiNH2 -LiBH4 system. This new ternary formulation performed much better than the well-known 2 LiNH2 ?? MgH2 system by 50 °C in the HT assay. The Li4(NH2)3BH4 is a low melting ionic liquid under our test conditions and facilitates the phase transformations required in the hydrogen storage reaction, which no longer relies on a higher energy solid state reaction pathway. Further study showed that the 0.6 LiNH2 ?? 0.3 MgH2 ?? 0.1 LiBH4 formulation was very stable with respect to ammonia and diborane desorption, the observed desorption was from hydrogen. This result could not have been anticipated and was made possible by the efficiency of HT combinatorial methods. Investigation of the analogous LiNH2 ?? LiBH4 ?? CaH2 phase diagram revealed new reversible hydrogen storage materials 0.625 LiBH4 + 0.375 CaH2 and 0.375 LiNH2 + 0.25 LiBH4 + 0.375 CaH2 operating at 1 wt. % reversible hydrogen below 175 °C. Powder x-ray diffraction revealed a new structure for the spent materials which had not been previously observed. While the storage capacity was not impressive, an important aspect is that it boron appears to participate in a low temperature reversible reaction. The last major area of study also focused

Lesch, David A; Adriaan Sachtler, J.W. J.; Low, John J; Jensen, Craig M; Ozolins, Vidvuds; Siegel, Don

2011-02-14T23:59:59.000Z

302

Discovery of Novel Complex Metal Hydrides for Hydrogen Storage through Molecular Modeling and Combinatorial Methods  

SciTech Connect

UOP LLC, a Honeywell Company, Ford Motor Company, and Striatus, Inc., collaborated with Professor Craig Jensen of the University of Hawaii and Professor Vidvuds Ozolins of University of California, Los Angeles on a multi-year cost-shared program to discover novel complex metal hydrides for hydrogen storage. This innovative program combined sophisticated molecular modeling with high throughput combinatorial experiments to maximize the probability of identifying commercially relevant, economical hydrogen storage materials with broad application. A set of tools was developed to pursue the medium throughput (MT) and high throughput (HT) combinatorial exploratory investigation of novel complex metal hydrides for hydrogen storage. The assay programs consisted of monitoring hydrogen evolution as a function of temperature. This project also incorporated theoretical methods to help select candidate materials families for testing. The Virtual High Throughput Screening served as a virtual laboratory, calculating structures and their properties. First Principles calculations were applied to various systems to examine hydrogen storage reaction pathways and the associated thermodynamics. The experimental program began with the validation of the MT assay tool with NaAlH4/0.02 mole Ti, the state of the art hydrogen storage system given by decomposition of sodium alanate to sodium hydride, aluminum metal, and hydrogen. Once certified, a combinatorial 21-point study of the NaAlH4 ?? LiAlH4 ??Mg(AlH4)2 phase diagram was investigated with the MT assay. Stability proved to be a problem as many of the materials decomposed during synthesis, altering the expected assay results. This resulted in repeating the entire experiment with a mild milling approach, which only temporarily increased capacity. NaAlH4 was the best performer in both studies and no new mixed alanates were observed, a result consistent with the VHTS. Powder XRD suggested that the reverse reaction, the regeneration of the alanate from alkali hydride, Al and hydrogen, was hampering reversibility. The reverse reaction was then studied for the same phase diagram, starting with LiH, NaH, and MgH2, and Al. The study was extended to phase diagrams including KH and CaH2 as well. The observed hydrogen storage capacity in the Al hexahydrides was less than 4 wt. %, well short of DOE targets. The HT assay came on line and after certification with studies on NaAlH4, was first applied to the LiNH2 - LiBH4 - MgH2 phase diagram. The 60-point study elucidated trends within the system locating an optimum material of 0.6 LiNH2 ?? 0.3 MgH2 ?? 0.1 LiBH4 that stored about 4 wt. % H2 reversibly and operated below 220 °C. Also present was the phase Li4(NH2)3BH4, which had been discovered in the LiNH2 -LiBH4 system. This new ternary formulation performed much better than the well-known 2 LiNH2 ?? MgH2 system by 50 °C in the HT assay. The Li4(NH2)3BH4 is a low melting ionic liquid under our test conditions and facilitates the phase transformations required in the hydrogen storage reaction, which no longer relies on a higher energy solid state reaction pathway. Further study showed that the 0.6 LiNH2 ?? 0.3 MgH2 ?? 0.1 LiBH4 formulation was very stable with respect to ammonia and diborane desorption, the observed desorption was from hydrogen. This result could not have been anticipated and was made possible by the efficiency of HT combinatorial methods. Investigation of the analogous LiNH2 ?? LiBH4 ?? CaH2 phase diagram revealed new reversible hydrogen storage materials 0.625 LiBH4 + 0.375 CaH2 and 0.375 LiNH2 + 0.25 LiBH4 + 0.375 CaH2 operating at 1 wt. % reversible hydrogen below 175 °C. Powder x-ray diffraction revealed a new structure for the spent materials which had not been previously observed. While the storage capacity was not impressive, an important aspect is that it boron appears to participate in a low temperature reversible reaction. The last major area of study also focused

Lesch, David A; Adriaan Sachtler, J.W. J.; Low, John J; Jensen, Craig M; Ozolins, Vidvuds; Siegel, Don

2011-02-14T23:59:59.000Z

303

Atomic Devices and Instrumentation Group  

Science Conference Proceedings (OSTI)

... 2001 and 2005, demonstrated an atomic clock physics package with ... magnetometers for magnetic anomaly detection, nuclear magnetic resonance ...

2013-08-09T23:59:59.000Z

304

Atom-Based Dimensional Metrology  

Science Conference Proceedings (OSTI)

... Awarded a five year, three phase DARPA contract to conduct collaborative research in atomically precise positioning, patterning and metrology ...

2013-04-19T23:59:59.000Z

305

Distributed Generation  

NLE Websites -- All DOE Office Websites (Extended Search)

with another option to reduce peak load, relieve transmission congestion, and improve power reliability. Backup generation is widely deployed across the United States. Carnegie...

306

Generation of attosecond electron bunches  

DOE Green Energy (OSTI)

Ultra-fast science is an important new research frontier that is driving the development of novel sources for generation of extremely short x-ray and electron pulses. Recent advances in femtosecond lasers have stimulated development of femtosecond x-ray sources that allow the study of matter at the time scale shorter than period of oscillations of atoms in molecules, {approx} 100 fs. The next breakthrough would be a source of electron pulses comparable with atomic periods {omega}{sup -1} {approx} 100 attosecond (10{sup -16} s), where {omega} is a transition frequency between atomic levels. This will open qualitatively new class of phenomena based on the interaction of atomic electrons in the medium with a collective electric field of electron pulses and not with their individual electrons. For example, one can expect coherent ionization losses that are proportional to a square number of electrons in the microbunch, phase synchronized excitation of medium followed by its relaxation with a radiation of a single-cycled optical pulse, excitation of entanglement states in the medium of atoms with few valence electrons, and possibly other new phenomena, yet to be identified. Simple estimation of coherent ionization losses shows that a 100 MeV, 100 attosecond electron pulse containing 10{sup 5} electrons will lose its total energy after propagating only {approx} 200{micro}m through liquid hydrogen. This is approximately 104 times shorter stopping range than it is for a long (on atomic scale) electron bunch.

Zholents, Alexander A.; Zolotorev, Max S.; Wan, Weishi

2001-06-18T23:59:59.000Z

307

Manipulating Synchronous Optical Signals with a Double $?$ Atomic Ensemble  

E-Print Network (OSTI)

We analyze a double $\\Lambda $ atomic configuration interacting with two signal beams and two control beams. Because of the quantum interference between the two $\\Lambda $ channels, the four fields are phase-matched in electromagnetically induced transparency. Our numerical simulation shows that this system is able to manipulate synchronous optical signals, such as generation of optical twin signals, data correction, signal transfer and amplification in the atomic storage.

Zhuan Li; De-Zhong Cao; Kaige Wang

2004-10-06T23:59:59.000Z

308

Effect of Temperature on NOx Reduction by Nitrogen Atom Injection  

DOE Green Energy (OSTI)

Chemical reduction of NO{sub x} can be accomplished by injection of nitrogen atoms into the diesel engine exhaust stream. The nitrogen atoms can be generated from a separate stream of pure N{sub 2} by means of plasma jets or non-thermal plasma reactors. This paper examines the effect of exhaust temperature on the NO{sub x} reduction efficiency that can be achieved by nitrogen atom injection. It is shown that to achieve a high NO{sub x} reduction efficiency at a reasonable power consumption penalty, the exhaust temperature needs to be 100 C or less.

Penetrante, B

1999-10-28T23:59:59.000Z

309

Why is hydrogen's atomic number 1?  

NLE Websites -- All DOE Office Websites (Extended Search)

the number of protons in an atom's nucleus. Hydrogen's atomic number is 1 because all hydrogen atoms contain exactly one proton. Author: Steve Gagnon, Science Education Specialist...

310

NIST: Phys. Lab. Brochure; Atomic Physics Div.  

Science Conference Proceedings (OSTI)

... ultra-cold atoms and investigate atom optics for innovative instrumentation. Measure and analyze spectra of highly ionized atoms for fusion energy ...

311

Development of an inter-atomic potential for the Pd-H binary system.  

DOE Green Energy (OSTI)

Ongoing research at Sandia National Laboratories has been in the area of developing models and simulation methods that can be used to uncover and illuminate the material defects created during He bubble growth in aging bulk metal tritides. Previous efforts have used molecular dynamics calculations to examine the physical mechanisms by which growing He bubbles in a Pd metal lattice create material defects. However, these efforts focused only on the growth of He bubbles in pure Pd and not on bubble growth in the material of interest, palladium tritide (PdT), or its non-radioactive isotope palladium hydride (PdH). The reason for this is that existing inter-atomic potentials do not adequately describe the thermodynamics of the Pd-H system, which includes a miscibility gap that leads to phase separation of the dilute (alpha) and concentrated (beta) alloys of H in Pd at room temperature. This document will report the results of research to either find or develop inter-atomic potentials for the Pd-H and Pd-T systems, including our efforts to use experimental data and density functional theory calculations to create an inter-atomic potential for this unique metal alloy system.

Zimmerman, Jonathan A.; Hoyt, Jeffrey John (McMaster University, Hamilton, Ontario, Canada); Leonard, Francois Leonard; Griffin, Joshua D.; Zhou, Xiao Wang

2007-09-01T23:59:59.000Z

312

Atomic data for fusion  

DOE Green Energy (OSTI)

This report provides a handbook of recommended cross-section and rate-coefficient data for inelastic collisions between hydrogen, helium and lithium atoms, molecules and ions, and encompasses more than 400 different reactions of primary interest in fusion research. Published experimental and theoretical data have been collected and evaluated, and the recommended data are presented in tabular, graphical and parametrized form. Processes include excitation and spectral line emission, charge exchange, ionization, stripping, dissociation and particle interchange reactions. The range of collision energies is appropriate to applications in fusion-energy research.

Hunter, H.T.; Kirkpatrick, M.I.; Alvarez, I.; Cisneros, C.; Phaneuf, R.A. (eds.) [eds.; Barnett, C.F.

1990-07-01T23:59:59.000Z

313

Cancer in atomic bomb survivors  

SciTech Connect

This book presents information on the following topics: sampling of atomic bomb survivors and method of cancer detection in Hiroshima and Nagasaki; atomic bomb dosimetry for epidemiological studies of survivors in Hiroshima and Nagasaki; tumor and tissue registries in Hiroshima and Nagasaki; the cancer registry in Nagasaki, with atomic bomb survivor data, 1973-1977; cancer mortality; methods for study of delayed health effects of a-bomb radiation; experimental radiation carcinogenesis in rodents; leukemia, multiple myeloma, and malignant lymphoma; cancer of the thyroid and salivary glands; malignant tumors in atomic bomb survivors with special reference to the pathology of stomach and lung cancer; colorectal cancer among atomic bomb survivors; breast cancer in atomic bomb survivors; and ovarian neoplasms in atomic bomb survirors.

Shigematsu, I.; Kagan, A.

1986-01-01T23:59:59.000Z

314

Particle size effect of hydride formation and surface hydrogen absorption of nanosized palladium catalysts : L{sub 3} edge vs K edge x-ray absorption spectroscopy.  

Science Conference Proceedings (OSTI)

The particle size effect on the formation of palladium hydride and on surface hydrogen adsorption was studied at room temperature using in situ X-ray absorption spectroscopy at the Pd K and L{sub 3} edges. Hydride formation was indirectly observed by lattice expansion in Pd K edge XANES spectra and by EXAFS analysis. Hydride formation was directly detected in the L{sub 3} edge spectra. A characteristic spectral feature caused by the formation of a Pd-H antibonding state showed strong particle size dependence. The L{sub 3} edge spectra were reproduced using full multiple scattering analysis and density of state calculations, and the contributions of bulk absorbed and surface hydrogen to the XANES spectra could be distinguished. The ratio of hydrogen on the surface versus that in the bulk increased with decreasing particle size, and smaller particles dissolved less hydrogen.

Tew, M. W.; Miller, J. T.; van Bokhoven, J. A. (Chemical Sciences and Engineering Division); ( SUF-USR); (ETH Zurich)

2009-08-01T23:59:59.000Z

315

Hydrogen atom in Palatini theories of gravity  

E-Print Network (OSTI)

We study the effects that the gravitational interaction of $f(R)$ theories of gravity in Palatini formalism has on the stationary states of the Hydrogen atom. We show that the role of gravity in this system is very important for lagrangians $f(R)$ with terms that grow at low curvatures, which have been proposed to explain the accelerated expansion rate of the universe. We find that new gravitationally induced terms in the atomic Hamiltonian generate a strong backreaction that is incompatible with the very existence of bound states. In fact, in the 1/R model, Hydrogen disintegrates in less than two hours. The universe that we observe is, therefore, incompatible with that kind of gravitational interaction. Lagrangians with high curvature corrections do not lead to such instabilities.

Gonzalo J. Olmo

2008-02-27T23:59:59.000Z

316

Questions and Answers - Does gravity affect atoms?  

NLE Websites -- All DOE Office Websites (Extended Search)

and Answers Main Index Next Question (Can you crush atoms?) Can you crush atoms? Does gravity affect atoms? Gravity affects atoms the same way it affects all other matter. Every...

317

Optics and interferometry with atoms and molecules  

E-Print Network (OSTI)

Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic ...

Cronin, Alexander D.

318

Engineering analysis of low enriched uranium fuel using improved zirconium hydride cross sections  

E-Print Network (OSTI)

A neutronic and thermal hydraulic analysis of the 1-MW TRIGA research reactor at the Texas A&M University Nuclear Science Center using a new low enriched uranium fuel (named 30/20 fuel) was completed. This analysis provides safety assessment for the change out of the existing high enriched uranium fuel to this high-burnup, low enriched uranium fuel design. The codes MCNP and Monteburns were utilized for the neutronic analysis while the code PARET was used to determine fuel and cladding temperatures. All of these simulations used improved zirconium hydride cross sections that were provided by Dr. Ayman Hawari at North Carolina State University. The neutronic and thermal analysis showed that the reactor will operate with approximately the same fuel lifetime as the current high enriched uranium fuel and stay within the thermal and safety limits for the facility. It was also determined that the control rod worths and the temperature coefficient of reactivity would provide sufficient negative reactivity to control the reactor during the fuelâ??s complete lifetime. An assessment of the fuelâ??s viability for use with the Advanced Fuel Cycle Initiativeâ??s Reactor Accelerator Coupling Experiments program was also performed. The objective of this study was to confirm the continued viability of these experiments with the reactor operating using this new fuel. For these experiments, the accelerator driven system must produce fission heating in excess of 1 kW when driven by a 20 kW accelerator system. This criterion was met using the new fuel. Therefore the change out of the fuel will not affect the viability of these experiments.

Candalino, Robert Wilcox

2006-08-01T23:59:59.000Z

319

Magnetometry with entangled atomic samples  

E-Print Network (OSTI)

We present a theory for the estimation of a scalar or a vector magnetic field by its influence on an ensemble of trapped spin polarized atoms. The atoms interact off-resonantly with a continuous laser field, and the measurement of the polarization rotation of the probe light, induced by the dispersive atom-light coupling, leads to spin-squeezing of the atomic sample which enables an estimate of the magnetic field which is more precise than that expected from standard counting statistics. For polarized light and polarized atoms, a description of the non-classical components of the collective spin angular momentum for the atoms and the collective Stokes vectors of the light-field in terms of effective gaussian position and momentum variables is practically exact. The gaussian formalism describes the dynamics of the system very effectively and accounts explicitly for the back-action on the atoms due to measurement and for the estimate of the magnetic field. Multi-component magnetic fields are estimated by the measurement of suitably chosen atomic observables and precision and efficiency is gained by dividing the atomic gas in two or more samples which are entangled by the dispersive atom-light interaction.

Vivi Petersen; Lars Bojer Madsen; Klaus Molmer

2004-09-28T23:59:59.000Z

320

Current status of environmental, health, and safety issues of nickel metal-hydride batteries for electric vehicles  

Science Conference Proceedings (OSTI)

This report identifies important environment, health, and safety issues associated with nickel metal-hydride (Ni-MH) batteries and assesses the need for further testing and analysis. Among the issues discussed are cell and battery safety, workplace health and safety, shipping requirements, and in-vehicle safety. The manufacture and recycling of Ni-MH batteries are also examined. This report also overviews the ``FH&S`` issues associated with other nickel-based electric vehicle batteries; it examines venting characteristics, toxicity of battery materials, and the status of spent batteries as a hazardous waste.

Corbus, D.; Hammel, C.J.; Mark, J.

1993-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Atomic Energy Commission Takes Over Responsibility for all Atomic...  

National Nuclear Security Administration (NNSA)

Takes Over Responsibility for all Atomic Energy Programs | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear...

322

Atomic total energies: Atomic Ref.Data Elec Struc Cal  

Science Conference Proceedings (OSTI)

... These tables contain the atomic total energies and orbital eigenvalues, for the ground electronic configuration of the elements H ... Definition of format ...

323

Atomic total energies: Atomic Ref. Data Elec. Struc. Cal.  

Science Conference Proceedings (OSTI)

... These tables contain the atomic total energies and orbital eigenvalues, for the ground electronic configuration of the elements H ... Definition of format ...

324

Laser Cooling and Cold Atomic Matter  

Science Conference Proceedings (OSTI)

Laser Cooling and Cold Atomic Matter: to advance the understanding and applications of cold atomic matter, including ...

2012-05-30T23:59:59.000Z

325

NIST - Atomic Energy Levels and Spectra Bibliographic ...  

Science Conference Proceedings (OSTI)

... in this database are from Bibliography on Atomic Energy Levels and ... references to atomic transition probabilities, line intensities, or broadening. ...

326

Radioisotope photoelectric generator  

SciTech Connect

This disclosure is directed to a radioisotope photoelectric generator for producing electrical energy. The construction of the generator is similar to that of a well-known storage battery. The generator is composed of alternate layers of high-Z, (high atomic-number) and low-Z (low atomic-number) material which are insulated by vacuum or other insulating material. Low-energy photons from a radioactive source interact predominantly with the high-Z material by the photoelectric process, ejecting photoelectrons whose energy extends up to the incident gamma-ray energy E. By selecting the high-Z material thickness to be less than one electron range (at energy E) and the low-Z material thickness to be more than one electron range, there is a net electron transfer from the high-Z plates to the low-Z plates because electrons are emitted predominantly from the high-Z plates and stop in the low-Z plates. After start-up, a potential difference will build up between the high-Z and low-Z plates. An upper limit for this potential difference in kilovolts is the energy E in keV. The high-Z plates are connected together electrically and the low-Z plates are connected together electrically thus forming a battery. The battery delivers power to an external electrical load, preferably but not necessarily a resistor, whose value is chosen to maximize the power delivered to the electrical load, to yield the voltage desired, to control the temperature of the plates, or a combination of such considerations.

Ritter, J.C.

1979-12-11T23:59:59.000Z

327

ATOMIC ENERGY COMMISSION  

Office of Legacy Management (LM)

' ' ATOMIC ENERGY COMMISSION Frank K. Pittman, Director, bivisioa of Waste &&gement and s- portation, Headquarters j CONTAMItUTED RX-AEC-OWNED OR LEASED FACILITIES' This memorandum responds to your TWX certain information on the above subject. the documentation necessary to answer your available due to the records disposal vailing at the time of release or From records that are available and from disc&ions with most familiar with the transfer operations, &have the current radiological conditibn of transferred property is adequate under present standards. The following tabulations follow the format suggested in your TWX and are grouped to an operations or contract r+ponsibility. A,I Ex-AEC Storage Sites - I r:/ National Stockpile Site '(NSS) and OperatEonal

328

NIST Atomic Spectra Bibliographic Databases  

Science Conference Proceedings (OSTI)

... The Atomic Energy Levels Data Center and Data Center on ... Reference Data Program (SRDP) and by NIST's Systems Integration for Manufacturing ...

2010-10-05T23:59:59.000Z

329

Technical Highlights Atomic Physics Division  

Science Conference Proceedings (OSTI)

... Physics Division is to develop and apply atomic physics research methods ... community, and to produce and critically compile physical reference data ...

2013-06-04T23:59:59.000Z

330

Atomic Devices and Instrumentation Group  

Science Conference Proceedings (OSTI)

... ten millionths of a second over the course of one day, and are paving the way for atomic-level timekeeping in portable, battery-operated systems ...

331

NIST: Atomic Spectroscopy Group - Homepage  

Science Conference Proceedings (OSTI)

... The program in atomic spectroscopy at NIST provides accurate reference data on spectral lines and energy levels for a wide variety of important ...

2013-07-31T23:59:59.000Z

332

Fully relativistic calculation of nuclear magnetic shieldings and indirect nuclear spin-spin couplings in group-15 and -16 hydrides  

Science Conference Proceedings (OSTI)

Fully relativistic calculations of the isotropic and anisotropic parts of both indirect nuclear spinspin couplings 1 J(X- H ) and 2 J( H-H ) and nuclear magnetic shieldings ?(X) and ?(H) for the group-15 and -16 hydrides are presented. Relativistic calculations were performed with DiracFock wave functions and the random phase approximation method. Results are compared to its nonrelativistic counterpart. Paramagnetic and diamagnetic contributions to the nuclear magnetic shielding constants are also reported. We found very large relativistic corrections to both properties in the sixth-row hydrides ( BiH 3 and PoH 2 ). Our calculations of the relativistic corrections to the isotropic part of ? at the heavy nucleus X show that it is roughly proportional to Z 3.2 in both series of molecules. Paramagnetic term ? p is more sensitive to the effects of relativity than the diamagnetic one ? d even though both have a behavior proportional to third power of the nuclear charge Z.

Sergio S. Gomez; Rodolfo H. Romero; Gustavo A. Aucar

2002-01-01T23:59:59.000Z

333

Effect of Ce composition on the structural and electronic characteristics of some metal hydride electrodes: A XANES and EXAFS investigation  

DOE Green Energy (OSTI)

Substitution of the B component in the prototype AB{sub 5} type (LaNi{sub 5}) metal hydride alloys have resulted in their increased acceptance as anodes for rechargeable alkaline batteries. Recently substitution of the A component (La) for imparting properties such as increased corrosion resistance has received attention. This investigation deals with the role of Ce as a substituent for the La and its effect in terms of corrosion resistance. The alloys chosen have the general composition of La{sub x}Ce{sub 1-x}B{sub 5} (x = 1, 0.8, 0.5 and 0.25) where B is Ni{sub 3.55}CO{sub 0.75}Mn{sub 0.4}Al{sub 0.3} together with alloys containing the mischmetal (Mm) as the A component (both synthetic and commercial). Electrochemical cycling results show that Ce lowers the capacity loss in the alloys and that this effect is not a simple function of the extent of lattice expansion during hydriding as was previously suggested. Correlation of the electrochemical and XAS results show that capacity loss is directly related to the extent of Ni corrosion. Effect of Ce substitution seems to result in a stable Ce oxide hydroxide coating which imparts the corrosion resistance.

Mukerjee, S.; McBreen, J.; Reilly, J.J.; Johnson, J.R.; Adzic, G. [Brookhaven National Lab., Upton, NY (United States); Kumar, M.P.S.; Zhang, W.; Srinivasan, S. [Texas A and M Univ., College Station, TX (United States). Center for Electrochemical Systems and Hydrogen Research

1994-12-31T23:59:59.000Z

334

UNDERSTANDING THE LOCAL ATOMIC LEVEL EFFECTS OF DOPANTS IN COMPLEX METAL HYDRIDES USING SYNCHROTRON XRAY ABSORPTION SPECTROSCOPY AND DENSITY FUNCTIONAL THEORY  

SciTech Connect

This work resulted in five peer-reviewed journal publications (appended), as well as one doctoral dissertation and two masters theses.

Dobbins, Tabbetha

2013-02-15T23:59:59.000Z

335

GENERATING CAPACITY  

E-Print Network (OSTI)

Evidence from the U.S. and some other countries indicates that organized wholesale markets for electrical energy and operating reserves do not provide adequate incentives to stimulate the proper quantity or mix of generating capacity consistent with mandatory reliability criteria. A large part of the problem can be associated with the failure of wholesale spot market prices for energy and operating reserves to rise to high enough levels during periods when generating capacity is fully utilized. Reforms to wholesale energy markets, the introduction of well-design forward capacity markets, and symmetrical treatment of demand response and generating capacity resources to respond to market and institutional imperfections are discussed. This policy reform program is compatible with improving the efficiency of spot wholesale electricity markets, the continued evolution of competitive retail markets, and restores incentives for efficient investment in generating capacity consistent with operating reliability criteria applied by system operators. It also responds to investment disincentives that have been associated with volatility in wholesale energy prices, limited hedging opportunities and to concerns about regulatory opportunism. 1

Paul L. Joskow; Paul L. Joskow; Paul L. Joskow

2006-01-01T23:59:59.000Z

336

EA-1053: Decontaminating and Decommissioning the General Atomics Hot Cell  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3: Decontaminating and Decommissioning the General Atomics 3: Decontaminating and Decommissioning the General Atomics Hot Cell Facility, San Diego, California EA-1053: Decontaminating and Decommissioning the General Atomics Hot Cell Facility, San Diego, California SUMMARY This EA evaluates the environmental impacts of the proposal for low-level radioactive and mixed wastes generated by decontaminating and decommissioning activities at the U.S. Department of Energy's General Atomics' Hot Cell Facility would be transported to either a DOE owned facility, such as the Hanford site in Washington, or to a commercial facility, such as Envirocare in Utah, for treatment and/or storage and disposal. PUBLIC COMMENT OPPORTUNITIES None available at this time. DOCUMENTS AVAILABLE FOR DOWNLOAD August 14, 1995 EA-1053: Finding of No Significant Impact

337

Laser system for secondary cooling of {sup 87}Sr atoms  

SciTech Connect

A laser system with a narrow generation line for secondary laser cooling of {sup 87}Sr atoms has been developed and investigated. It is planned to use ultracold {sup 87}Sr atoms loaded in an optical lattice in an optical frequency standard. To this end, a 689-nm semiconductor laser has been stabilised using an external reference ultrastable cavity with vibrational and temperature compensation near the critical point. The lasing spectral width was 80 Hz (averaging time 40 ms), and the frequency drift was at a level of 0.3 Hz s{sup -1}. Comparison of two independent laser systems yielded a minimum Allan deviation: 2 Multiplication-Sign 10{sup -14} for 300-s averaging. It is shown that this system satisfies all requirements necessary for secondary cooling of 87Sr atoms using the spectrally narrow {sup 1}S{sub 0} - {sup 3}P{sub 1} transition ({lambda} = 689 nm). (cooling of atoms)

Khabarova, K Yu; Slyusarev, S N; Strelkin, S A; Belotelov, G S; Kostin, A S; Pal'chikov, Vitaly G; Kolachevsky, Nikolai N

2012-11-30T23:59:59.000Z

338

THE BIRTH OF NUCLEAR-GENERATED ELECTRICITY  

NLE Websites -- All DOE Office Websites (Extended Search)

BIRTH OF NUCLEAR-GENERATED ELECTRICITY BIRTH OF NUCLEAR-GENERATED ELECTRICITY The first time that electricity was generated from nuclear energy occurred in an experimental breeder reactor in Idaho in 1951. The idea for a breeder reactor (a reactor that could produce more fuel than it uses) first occurred to scientists working on the nation's wartime atomic energy program in the early 1940's. Experimental evidence indicated that the breeding of nuclear fuel was possible in a properly designed reactor, but time and resources were not then available to pursue the idea After the war, the newly established Atomic Energy Commission (now the Department of Energy) assigned some of the nation's nuclear skills and resources to developing peaceful uses of the atom. The large bodies of uranium ore found in the 1950's were

339

Atoms.inp Archive: Crystallographic Data from GSECARS  

DOE Data Explorer (OSTI)

The Atoms.inp Archive is a collection of crystallographic data for use in XAFS analysis. The crystallographic data is stored as atoms.inp files, which contain all the information necessary to describe the crystal, and can be used by the program ATOMS to generate feff.inp files. These files can then be used by the FEFF program [See http://leonardo.phys.washington.edu/feff/] to calculate a theoretical XAFS spectrum for the crystal. This archive exists because it can take a considerable amount of time to locate a suitable reference for a model structure to use for making theoretical XAFS standards. Even then, references sometimes give non-standard or incomplete crystallographic notation that ATOMS has difficulty interpreting. All of this means that getting a reliable atoms.inp file can take quite a bit of effort. It is hoped that this collection of well-documented and well-tested atoms.inp files will eliminate much of the work in creating theoretical XAFS standards from FEFF. [Taken from http://cars9.uchicago.edu/~newville/adb/]. The collection currently has more than 200 crystal structures, 2748 data files, and it continues to expand. The collection is related to the UWXAFS Project [http://depts.washington.edu/uwxafs/] and to the work of the Consortium for Advanced Radiation Sources (CARS). After searching the Archive, a user may also choose to run the web version of ATOMS software.

Newville, Matthew

340

Study of atomic physics and population inversions with plasma focus  

SciTech Connect

The plasma focus can be used to generate high temperature and high density plasmas. Neon-like plasmas have previously been studied in Z-pinches and laser produced plasmas as sources for XUV and x-ray lasers. The plasma focus provides a simple and inexpensive source for studying atomic physics of highly ionized atoms. A detailed understanding of atomic physics at high temperatures, densities, and megagauss magnetic fields is necessary for possible x-ray laser designs. Methods that are generally used for obtaining population inversions include collisional ionization of the inner shells of multi-electron atoms and ions, photoexcitation, and electron collisional excitation of ions, collisional combination of ions, and atom-ion resonant charge exchange. We will discuss some possible experiments to help understand the atomic physics under the above condition. Some ideas and calculations will be given to show the feasibility of doing atomic physics relating to x-ray lasers with a plasma focus. 13 refs., 2 figs.

Oona, H.; Hodgdon, M.L.; Rickel, D.G.; Freeman, B.L.

1989-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Atomic Inference from Weak Gravitational Lensing Data  

SciTech Connect

We present a novel approach to reconstructing the projected mass distribution from the sparse and noisy weak gravitational lensing shear data. The reconstructions are regularized via the knowledge gained from numerical simulations of clusters, with trial mass distributions constructed from n NFW profile ellipsoidal components. The parameters of these ''atoms'' are distributed a priori as in the simulated clusters. Sampling the mass distributions from the atom parameter probability density function allows estimates of the properties of the mass distribution to be generated, with error bars. The appropriate number of atoms is inferred from the data itself via the Bayesian evidence, and is typically found to be small, reecting the quality of the data. Ensemble average mass maps are found to be robust to the details of the noise realization, and succeed in recovering the demonstration input mass distribution (from a realistic simulated cluster) over a wide range of scales. As an application of such a reliable mapping algorithm, we comment on the residuals of the reconstruction and the implications for predicting convergence and shear at specific points on the sky.

Marshall, Phil; /KIPAC, Menlo Park

2005-12-14T23:59:59.000Z

342

Model based design of an automotive-scale, metal hydride hydrogen storage system.  

SciTech Connect

Sandia and General Motors have successfully designed, fabricated, and experimentally operated a vehicle-scale hydrogen storage system using the complex metal hydride sodium alanate. Over the 6 year project, the team tackled the primary barriers associated with storage and delivery of hydrogen including mass, volume, efficiency and cost. The result was the hydrogen storage demonstration system design. The key technologies developed for this hydrogen storage system include optimal heat exchange designs, thermal properties enhancement, a unique catalytic hydrogen burner and energy efficient control schemes. The prototype system designed, built, and operated to demonstrate these technologies consists of four identical hydrogen storage modules with a total hydrogen capacity of 3 kg. Each module consists of twelve stainless steel tubes that contain the enhanced sodium alanate. The tubes are arranged in a staggered, 4 x 3 array and enclosed by a steel shell to form a shell and tube heat exchanger. Temperature control during hydrogen absorption and desorption is accomplished by circulating a heat transfer fluid through each module shell. For desorption, heat is provided by the catalytic oxidation of hydrogen within a high efficiency, compact heat exchanger. The heater was designed to transfer up to 30 kW of heat from the catalytic reaction to the circulating heat transfer fluid. The demonstration system module design and the system control strategies were enabled by experiment-based, computational simulations that included heat and mass transfer coupled with chemical kinetics. Module heat exchange systems were optimized using multi-dimensional models of coupled fluid dynamics and heat transfer. Chemical kinetics models were coupled with both heat and mass transfer calculations to design the sodium alanate vessels. Fluid flow distribution was a key aspect of the design for the hydrogen storage modules and computational simulations were used to balance heat transfer with fluid pressure requirements. An overview of the hydrogen storage system will be given, and examples of these models and simulation results will be described and related to component design. In addition, comparisons of demonstration system experimental results to model predictions will be reported.

Johnson, Terry Alan; Kanouff, Michael P.; Jorgensen, Scott W. (General Motors R& D); Dedrick, Daniel E.; Evans, Gregory Herbert

2010-11-01T23:59:59.000Z

343

Dartmouth College Computer Science Technical Report PCS-TR99-348 A Two Dimensional Crystalline Atomic Unit Modular Self-reconfigurable Robot  

E-Print Network (OSTI)

). These sensors would be useful in research for generating a greater understanding of the atomization process of the best available models and a heuristic understanding of atomization can be used with sensors to develop

344

Atomic Energy for Military Purposes  

E-Print Network (OSTI)

Atomic Energy for Military Purposes: The Official Report on the Development of the Atomic Bomb member of the project, to draft a report about its activities. Smyth completed the report in the summer, in a censored version. On August 11, 1945, five days after the Allies dropped the first nuclear bomb on Japan

Landweber, Laura

345

THE DEVELOPMENT OF ATOMIC LAW  

SciTech Connect

Since a uniform federal statute hss not been passed in the German Federal Republic, the development of atomic law has centered around the formation of the Federal Ministry for Atomic Affairs, appeal to the German Commission, and the enactment of temporary laws in several of the states. (J.S.R.)

Fischerhof, H.

1958-08-01T23:59:59.000Z

346

AtomicNuclear Properties  

NLE Websites -- All DOE Office Websites (Extended Search)

HTML_PAGES HTML_PAGES This AtomicNuclearProperties page is under intermittent development. Suggestions and comments are welcome. Please report errors. Chemical elements: For entries in red, a pull-down menu permits selection of the physical state. Cryogenic liquid densties are at the boiling point at 1 atm. 0n 1Ps 1H 2He 3Li 4Be 5B 6C 7N 8O 9F 10Ne 11Na 12Mg 13Al 14Si 15P 16S 17Cl 18Ar 19K 20Ca 21Sc 22Ti 23V 24Cr 25Mn 26Fe 27Co 28Ni 29Cu 30Zn 31Ga 32Ge 33As 34Se 35Br 36Kr 37Rb 38Sr 39Y 40Zr 41Nb 42Mo 43Tc 44Ru 45Rh 46Pd 47Ag 48Cd 49In 50Sn 51Sb 52Te 53I 54Xe 55Cs 56Ba 57La 72Hf 73Ta 74W 75Re 76Os 77Ir 78Pt 79Au 80Hg 81Tl 82Pb 83Bi 84Po 85At 86Rn 87Fr 88Ra 89Ac 104Rf 105Db 106Sg 107Bh 108Hs 109Mt 110Ds 111Rg 112 113 114 115 116 mt 118

347

Effect of amorphous Mg{sub 50}Ni{sub 50} on hydriding and dehydriding behavior of Mg{sub 2}Ni alloy  

SciTech Connect

Composite Mg{sub 2}Ni (25 wt.%) amorphous Mg{sub 50}Ni{sub 50} was prepared by mechanical milling starting with nanocrystalline Mg{sub 2}Ni and amorphous Mg{sub 50}Ni{sub 50} powders, by using a SPEX 8000 D mill. The morphological and microstructural characterization of the powders was performed via scanning electron microscopy and X-ray diffraction. The hydriding characterization of the composite was performed via a solid gas reaction method in a Sievert's-type apparatus at 363 K under an initial hydrogen pressure of 2 MPa. The dehydriding behavior was studied by differential thermogravimetry. On the basis of the results, it is possible to conclude that amorphous Mg{sub 50}Ni{sub 50} improved the hydriding and dehydriding kinetics of Mg{sub 2}Ni alloy upon cycling. A tentative rationalization of experimental observations is proposed. - Research Highlights: {yields} First study of the hydriding behavior of composite Mg{sub 2}Ni (25 wt.%) amorphous Mg{sub 50}Ni{sub 50}. {yields} Microstructural characterization of composite material using XRD and SEM was obtained. {yields} An improved effect of Mg{sub 50}Ni{sub 50} on the Mg{sub 2}Ni hydriding behavior was verified. {yields} The apparent activation energy for the hydrogen desorption of composite was obtained.

Guzman, D., E-mail: danny.guzman@uda.cl [Departamento de Ingenieria en Metalurgia, Facultad de Ingenieria, Universidad de Atacama y Centro Regional de Investigacion y Desarrollo Sustentable de Atacama (CRIDESAT), Av. Copayapu 485, Copiapo (Chile); Ordonez, S. [Departamento de Ingenieria Metalurgica, Facultad de Ingenieria, Universidad de Santiago de Chile, Av. Lib. Bernardo O'Higgins 3363, Santiago (Chile); Fernandez, J.F.; Sanchez, C. [Departamento de Fisica de Materiales, Facultad de Ciencias, Universidad Autonoma de Madrid, Cantoblanco 28049, Madrid (Spain); Serafini, D. [Departamento de Fisica, Facultad de Ciencias, Universidad de Santiago de Chile and Center for Interdisciplinary Research in Materials, CIMAT, Av. Lib. Bernardo O'Higgins 3363, Santiago (Chile); Rojas, P.A. [Escuela de Ingenieria Mecanica, Facultad de Ingenieria, Av. Los Carrera 01567, Quilpue, Pontificia Universidad Catolica de Valparaiso, PUCV (Chile); Aguilar, C. [Departamento de Ingenieria Metalurgica y Materiales, Universidad Tecnica Federico Santa Maria, Av. Espana 1680, Valparaiso (Chile); Tapia, P. [Departamento de Ingenieria en Metalurgia, Facultad de Ingenieria, Universidad de Atacama, Av. Copayapu 485, Copiapo (Chile)

2011-04-15T23:59:59.000Z

348

Atomic, Molecular & Optical Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Atomic, Molecular and Optical Sciences Atomic, Molecular and Optical Sciences The goal of the program is to understand the structure and dynamics of atoms and molecules using photons and ions as probes. The current program is focussed on studying inner-shell photo-ionization and photo-excitation of atoms and molecules, molecular orientation effects in slow collisions, slowing and cooling molecules, and X-ray photo-excitation of laser-dressed atoms. The experimental and theoretical efforts are designed to break new ground and to provide basic knowledge that is central to the programmatic goals of the Department of Energy (DOE). Unique LBNL facilities such as the Advanced Light Source (ALS), the ECR ion sources at the 88-inch cyclotron, and the National Energy Research Scientific Computing Center (NERSC) are

349

Spectral Emission of Moving Atom  

E-Print Network (OSTI)

A renewed analysis of the H.E. Ives and G.R. Stilwell's experiment on moving hydrogen canal rays (J. Opt. Soc. Am., 1938, v.28, 215) concludes that the spectral emission of a moving atom exhibits always a redshift which informs not the direction of the atom's motion. The conclusion is also evident from a simple energy relation: atomic spectral radiation is emitted as an orbiting electron consumes a portion of its internal energy on transiting to a lower-energy state which however has in a moving atom an additional energy gain; this results in a redshift in the emission frequency. Based on auxiliary experimental information and a scheme for de Broglie particle formation, we give a vigorous elucidation of the mechanism for deceleration radiation of atomic electron; the corresponding prediction of the redshift is in complete agreement with the Ives and Stilwell's experimental formula.

J. X. Zheng-Johansson

2006-06-17T23:59:59.000Z

350

NOx reduction by electron beam-produced nitrogen atom injection  

DOE Patents (OSTI)

Deactivated atomic nitrogen generated by an electron beam from a gas stream containing more than 99% N.sub.2 is injected at low temperatures into an engine exhaust to reduce NOx emissions. High NOx reduction efficiency is achieved with compact electron beam devices without use of a catalyst.

Penetrante, Bernardino M. (San Ramon, CA)

2002-01-01T23:59:59.000Z

351

Anticipating the atom: popular perceptions of atomic power before Hiroshima  

E-Print Network (OSTI)

Before Hiroshima made the Bomb an object of popular concern, possible implications and applications of atomic physics had been discussed in the public forum. The new science of X-rays and radium promised the possibilities of unlimited energy and the transmutation of elements in the two decades leading up to World War 1. During the twenties, as scientific method struggled to keep pace with atomic theory, discussion centered on the feasibility of atomic disintegration as an energy source and the many uses of radium. The 1927 case of the New Jersey Radium Dial Painters, who sued their employers for compensation after contracting radium poisoning, revealed a dark side to the new science, that, along with the development of artificial radioactive isotopes by the Jollot-Curies in Paris, and, in Italy, Enrico Fenni's neutron bombardment experiments, sobered attitudes toward the ever-increasing probability of atomic power. When Otto Hahn finally split the atom in 1938, it opened the way to the practical industrial use of atomic fission, and stimulated a flurry of newspaper and magazine articles before World War 11 brought about censorship. Popular entertainment through 1945 reflects the extent to which atomic power had entered the public awareness. Atomic themes and motifs appeared in English language fiction as early as 1895, as did discussions of the social implications of the new science. Such popular culture imagery, including motion pictures and comic book superheroes, that presented the atom to mass audiences provide insight into the popular perceptions at the time, and to the shaping of attitudes toward the Bomb after Hiroshima.

d'Emal, Jacques-Andre Christian

1994-01-01T23:59:59.000Z

352

Magnetocumulative generator  

DOE Patents (OSTI)

An improved magnetocumulative generator is described that is useful for producing magnetic fields of very high energy content over large spatial volumes. The polar directed pleated magnetocumulative generator has a housing providing a housing chamber with an electrically conducting surface. The chamber forms a coaxial system having a small radius portion and a large radius portion. When a magnetic field is injected into the chamber, from an external source, most of the magnetic flux associated therewith positions itself in the small radius portion. The propagation of an explosive detonation through high-explosive layers disposed adjacent to the housing causes a phased closure of the chamber which sweeps most of the magnetic flux into the large radius portion of the coaxial system. The energy content of the magnetic field is greatly increased by flux stretching as well as by flux compression. The energy enhanced magnetic field is utilized within the housing chamber itself.

Pettibone, J.S.; Wheeler, P.C.

1981-06-08T23:59:59.000Z

353

Thermoelectric generator  

DOE Patents (OSTI)

A thermoelectric generator having a rigid coupling or stack'' between the heat source and the hot strap joining the thermoelements is described. The stack includes a member of an insulating material, such as ceramic, for electrically isolating the thermoelements from the heat source, and a pair of members of a ductile material, such as gold, one each on each side of the insulating member, to absorb thermal differential expansion stresses in the stack. (Official Gazette)

Pryslak, N.E.

1974-02-26T23:59:59.000Z

354

Photon generator  

DOE Patents (OSTI)

A photon generator includes an electron gun for emitting an electron beam, a laser for emitting a laser beam, and an interaction ring wherein the laser beam repetitively collides with the electron beam for emitting a high energy photon beam therefrom in the exemplary form of x-rays. The interaction ring is a closed loop, sized and configured for circulating the electron beam with a period substantially equal to the period of the laser beam pulses for effecting repetitive collisions.

Srinivasan-Rao, Triveni (Shoreham, NY)

2002-01-01T23:59:59.000Z

355

PLASMA GENERATOR  

DOE Patents (OSTI)

This patent describes apparatus for producing an electricity neutral ionized gas discharge, termed a plasma, substantially free from contamination with neutral gas particles. The plasma generator of the present invention comprises a plasma chamber wherein gas introduced into the chamber is ionized by a radiofrequency source. A magnetic field is used to focus the plasma in line with an exit. This magnetic field cooperates with a differential pressure created across the exit to draw a uniform and uncontaminated plasma from the plasma chamber.

Foster, J.S. Jr.

1958-03-11T23:59:59.000Z

356

Atomic clocks with suppressed blackbody radiation shift  

E-Print Network (OSTI)

We develop a nonstandard concept of atomic clocks where the blackbody radiation shift (BBRS) and its temperature fluctuations can be dramatically suppressed (by one to three orders of magnitude) independent of the environmental temperature. The suppression is based on the fact that in a system with two accessible clock transitions (with frequencies v1 and v2) which are exposed to the same thermal environment, there exists a "synthetic" frequency v_{syn} (v1-e12 v2) largely immune to the BBRS. As an example, it is shown that in the case of ion 171Yb+ it is possible to create a clock in which the BBRS can be suppressed to the fractional level of 10^{-18} in a broad interval near room temperature (300\\pm 15 K). We also propose a realization of our method with the use of an optical frequency comb generator stabilized to both frequencies v1 and v2. Here the frequency v_{syn} is generated as one of the components of the comb spectrum and can be used as an atomic standard.

V. I. Yudin; A. V. Taichenachev; M. V. Okhapkin; S. N. Bagayev; Chr. Tamm; E. Peik; N. Huntemann; T. E. Mehlstaubler; F. Riehle

2011-03-03T23:59:59.000Z

357

Manhattan Project: Adventures Inside the Atom  

Office of Scientific and Technical Information (OSTI)

ADVENTURES INSIDE THE ATOM ADVENTURES INSIDE THE ATOM General Electric, National Archives (1948) Resources > Library Below is Adventures Inside the Atom, a comic book history of nuclear energy that was produced in 1948 by the General Electric Company. Scroll down to view the full-size images of each page. This publication was produced at the request of the the Assistant Manager for Public Education, Oak Ridge Operations Office, Atomic Energy Commission. It is reproduced here via the National Archives. Adventures Inside the Atom, p. 1 Adventures Inside the Atom, p. 2 Adventures Inside the Atom, p. 3 Adventures Inside the Atom, p. 4 Adventures Inside the Atom, p. 5 Adventures Inside the Atom, p. 6 Adventures Inside the Atom, p. 7 Adventures Inside the Atom, p. 8 Adventures Inside the Atom, p. 9

358

In-situ control system for atomization  

DOE Patents (OSTI)

Melt atomizing apparatus comprising a melt supply orifice for supplying the melt for atomization and gas supply orifices proximate the melt supply orifice for supplying atomizing gas to atomize the melt as an atomization spray is disclosed. The apparatus includes a sensor, such as an optical and/or audio sensor, for providing atomization spray data, and a control unit responsive to the sensed atomization spray data for controlling at least one of the atomizing gas pressure and an actuator to adjust the relative position of the gas supply orifice and melt supply in a manner to achieve a desired atomization spray. 3 figs.

Anderson, I.E.; Figliola, R.S.; Terpstra, R.L.

1995-06-13T23:59:59.000Z

359

In-situ control system for atomization  

DOE Patents (OSTI)

Melt atomizing apparatus comprising a melt supply orifice for supplying the melt for atomization and gas supply orifices proximate the melt supply orifice for supplying atomizing gas to atomize the melt as an atomization spray. The apparatus includes a sensor, such as an optical and/or audio sensor, for providing atomization spray data, and a control unit responsive to the sensed atomization spray data for controlling at least one of the atomizing gas pressure and an actuator to adjust the relative position of the gas supply orifice and melt supply in a manner to achieve a desired atomization spray.

Anderson, Iver E. (Ames, IA); Figliola, Richard S. (Central, SC); Terpstra, Robert L. (Ames, IA)

1995-06-13T23:59:59.000Z

360

Comprehensive online Atomic Database Management System (DBMS) with Highly Qualified Computing Capabilities  

E-Print Network (OSTI)

The intensive need of atomic data is expanding continuously in a wide variety of applications (e.g. fusion energy and astrophysics, laser-produced, plasma researches, and plasma processing).This paper will introduce our ongoing research work to build a comprehensive, complete, up-to-date, user friendly and online atomic Database Management System (DBMS) namely called AIMS by using SQLite (http://www.sqlite.org/about.html)(8). Programming language tools and techniques will not be covered here. The system allows the generation of various atomic data based on professional online atomic calculators. The ongoing work is a step forward to bring detailed atomic model accessible to a wide community of laboratory and astrophysical plasma diagnostics. AIMS is a professional worldwide tool for supporting several educational purposes and can be considered as a complementary database of IAEA atomic databases. Moreover, it will be an exceptional strategy of incorporating the output data of several atomic codes to external ...

Tahat, Amani

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Supersonic coal water slurry fuel atomizer  

DOE Patents (OSTI)

A supersonic coal water slurry atomizer utilizing supersonic gas velocities to atomize coal water slurry is provided wherein atomization occurs externally of the atomizer. The atomizer has a central tube defining a coal water slurry passageway surrounded by an annular sleeve defining an annular passageway for gas. A converging/diverging section is provided for accelerating gas in the annular passageway to supersonic velocities.

Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA); Balsavich, John (Foxborough, MA)

1991-01-01T23:59:59.000Z

362

Questions and Answers - Does an atom smasher really smash atoms?  

NLE Websites -- All DOE Office Websites (Extended Search)

is an accelerator? is an accelerator? Previous Question (What is an accelerator?) Questions and Answers Main Index Next Question (Where and how do you get your electrons for your accelerator?) Where and how do you get yourelectrons for your accelerator? Does an atom smasher really smash atoms? Well, yes, they do, but we now prefer to call them by their less aggression-centered name, "particle harmony disrupters." Of course some atom smashers do much more smashing than others. We use electrons in our accelerator to study the nucleus of an atom. Remember that electrons are negative, as are the electrons surrounding the target. Since like charged particles repel each other, our particles have to have enough energy to blast through that electron cloud to get to the nucleus. The electrons then

363

Nondegenerate parametric down conversion in coherently prepared two-level atomic gas  

E-Print Network (OSTI)

We describe parametric down conversion process in a two-level atomic gas, where the atoms are in a superposition state of relevant energy levels. This superposition results in splitting of the phase matching condition into three different conditions. Another, more important, peculiarity of the system under discussion is the nonsaturability of amplification coefficients with increasing pump wave intensity, under "sideband" generation conditions.

Gevorg Muradyan; Atom Zh. Muradyan

2008-07-14T23:59:59.000Z

364

Nondegenerate parametric down conversion in coherently prepared two-level atomic gas  

E-Print Network (OSTI)

We describe parametric down conversion process in a two-level atomic gas, where the atoms are in a superposition state of relevant energy levels. This superposition results in splitting of the phase matching condition into three different conditions. Another, more important, peculiarity of the system under discussion is the nonsaturability of amplification coefficients with increasing pump wave intensity, under "sideband" generation conditions.

Muradyan, Gevorg

2008-01-01T23:59:59.000Z

365

HEAT GENERATION  

DOE Patents (OSTI)

Heat is generated by the utilization of high energy neutrons produced as by nuclear reactions between hydrogen isotopes in a blanket zone containing lithium, a neutron moderator, and uranium and/or thorium effective to achieve multtplicatton of the high energy neutron. The rnultiplied and moderated neutrons produced react further with lithium-6 to produce tritium in the blanket. Thermal neutron fissionable materials are also produced and consumed in situ in the blanket zone. The heat produced by the aggregate of the various nuclear reactions is then withdrawn from the blanket zone to be used or otherwise disposed externally. (AEC)

Imhoff, D.H.; Harker, W.H.

1963-12-01T23:59:59.000Z

366

Magnetocumulative generator  

DOE Patents (OSTI)

An improved magnetocumulative generator is described that is useful for producing magnetic fields of very high energy content over large spatial volumes. The polar directed pleated magnetocumulative generator has a housing (100, 101, 102, 103, 104, 105) providing a housing chamber (106) with an electrically conducting surface. The chamber (106) forms a coaxial system having a small radius portion and a large radius portion. When a magnetic field is injected into the chamber (106), from an external source, most of the magnetic flux associated therewith positions itself in the small radius portion. The propagation of an explosive detonation through high-explosive layers (107, 108) disposed adjacent to the housing causes a phased closure of the chamber (106) which sweeps most of the magnetic flux into the large radius portion of the coaxial system. The energy content of the magnetic field is greatly increased by flux stretching as well as by flux compression. The energy enhanced magnetic field is utilized within the housing chamber itself.

Pettibone, Joseph S. (Livermore, CA); Wheeler, Paul C. (Livermore, CA)

1983-01-01T23:59:59.000Z

367

SYNTHESIS OF METAL HYDRIDES BY MECHANICAL ALLOYING IN AN ATTRITOR MILL: FY07 STATUS REPORT  

DOE Green Energy (OSTI)

The objective of this task was to demonstrate that metal hydrides could be produced by mechanical alloying in the quantities needed to support the tritium production facilities at the Savannah River Site. The objective for the FY07 portion of this task was to demonstrate the production of Zr-Fe getter materials by mechanical alloying and begin to optimize the milling parameters. Three starting compositions (ratios of elemental Zr and Fe powders) were selected and attritor milled under argon for times of 8 to 60 hours. Hexane and liquid nitrogen were used as process control agents. In general, milling times of at least 24 hours were required to form the desired Zr{sub 2}Fe and Zr{sub 3}Fe phases, although a considerable amount of unalloyed Zr and Fe remained. Milling in liquid nitrogen does not appear to provide any advantages over milling in hexane, particularly due to the formation of ZrN after longer milling times. Carbides of Zr formed during some of the milling experiments in hexane. Formation of carbides during milling appears to be much less of an issue than formation of nitrides, although some of the phases that were not able to be identified in the XRD results may also be carbides. Additional XRD experiments should be designed to improve signal to noise ratio (i.e., longer count times) and use a wider scan range to better identify phases that were not clear in the original data. Elemental Zr was present in the as-milled material but not detected after annealing for milling times of 48 and 60 hours. It may be that after intimate mixing of the powders in the attritor mill the annealing temperature was sufficient to allow for the formation of a Zr-Fe alloy. The phase diagram for the binary Zr-Fe system agrees with this proposition. If this is the case, then the annealing conditions should also be investigated and optimized to form as much of the Zr-Fe alloy as possible in the milled powder. Also, this finding would mean that milling times of more than 48 hours are not necessary. Further investigation of this conversion is necessary, and could provide an opportunity for reducing the amount of unreacted metal powder after milling. Elemental Fe remained in all of the powders after annealing for all of the milling times tested. This may indicate that the ratio of Zr to Fe needs to be increased in order to improve the yield of the desired Zr-Fe alloys. Particle size analysis data are presented to aid in the selection of filters for future hydrogen sorption testing. Based on the XRD results, four samples were suggested for further XRD analysis and hydrogen sorption testing: (1) Zr{sub 2}Fe, 24 hr milling, annealed; (2) Zr{sub 2}Fe, 24 hr milling in LN{sub 2}, annealed; (3) Zr{sub 3}Fe, 24 hr milling, annealed; and (4) Zr{sub 3}Fe, 48 hr milling, annealed. These four samples showed the largest volume (based on relative peak intensities) of the desired Zr{sub 2}Fe and Zr{sub 3}Fe alloys.

Fox, K

2007-11-08T23:59:59.000Z

368

Discovery of Novel Complex Metal Hydrides for Hydrogen Storage through Molecular Modeling and Combinatorial Methods  

DOE Green Energy (OSTI)

Once certified, a combinatorial 21-point study of the NaAlH4 ?? LiAlH4 ??Mg(AlH4)2 phase diagram was investigated with the MT assay. Stability proved to be a problem as many of the materials decomposed during synthesis, altering the expected assay results. This resulted in repeating the entire experiment with a mild milling approach, which only temporarily increased capacity. NaAlH4 was the best performer in both studies and no new mixed alanates were observed, a result consistent with the VHTS. Powder XRD suggested that the reverse reaction, the regeneration of the alanate from alkali hydride, Al and hydrogen, was hampering reversibility. The reverse reaction was then studied for the same phase diagram, starting with LiH, NaH, and MgH2, and Al. The study was extended to phase diagrams including KH and CaH2 as well. The observed hydrogen storage capacity in the Al hexahydrides was less than 4 wt. %, well short of DOE targets. The HT assay came on line and after certification with studies on NaAlH4, was first applied to the LiNH2 - LiBH4 - MgH2 phase diagram. The 60-point study elucidated trends within the system locating an optimum material of 0.6 LiNH2 ?? 0.3 MgH2 ?? 0.1 LiBH4 that stored about 4 wt. % H2 reversibly and operated below 220 °C. Also present was the phase Li4(NH2)3BH4, which had been discovered in the LiNH2 -LiBH4 system. This new ternary formulation performed much better than the well-known 2 LiNH2 ?? MgH2 system by 50 °C in the HT assay. The Li4(NH2)3BH4 is a low melting ionic liquid under our test conditions and facilitates the phase transformations required in the hydrogen storage reaction, which no longer relies on a higher energy solid state reaction pathway. Further study showed that the 0.6 LiNH2 ?? 0.3 MgH2 ?? 0.1 LiBH4 formulation was very stable with respect to ammonia and diborane desorption, the observed desorption was from hydrogen. This result could not have been anticipated and was made possible by the efficiency of HT combinatorial methods. Investigation of the analogous LiNH2 ?? LiBH4 ?? CaH2 phase diagram revealed new reversible hydrogen storage materials 0.625 LiBH4 + 0.375 CaH2 and 0.375 LiNH2 + 0.25 LiBH4 + 0.375 CaH2 operating at 1 wt. % reversible hydrogen below 175 °C. Powder x-ray diffraction revealed a new structure for the spent materials which had not been previously observed. While the storage capacity was not impressive, an important aspect is that it boron appears to participate in a low temperature reversible reaction. The last major area of study also focused

Lesch, David A; Adriaan Sachtler, J.W. J.; Low, John J; Jensen, Craig M; Ozolins, Vidvuds; Siegel, Don

2011-02-14T23:59:59.000Z

369

UNITED STATES ATOMIC ENERGY COMMISSION  

Office of Legacy Management (LM)

producing uranium for the Mo"hz,t,a, Projec, can best be qwtcd Irom the Smyth official report - Atomic Energy - . ' .: CCL, + NaCl - ."-l Figure 6. apparatus used in electrcdytic...

370

u. S. Atomic Energy Commission  

Office of Legacy Management (LM)

October 31, 1949 Manager of Operations u. S. Atomic Energy Commission R. 0. Box 30, Ansonia Station New York ES, N. Y. MATERIALS 5+k& hJf Reference: SK:BL Attention: Mr. R. J....

371

Lightweight Metal Hydrides for Hydrogen Storage - DOE Hydrogen and Fuel Cells Program FY 2012 Annual Progress Report  

NLE Websites -- All DOE Office Websites (Extended Search)

DOE Hydrogen and Fuel Cells Program FY 2012 Annual Progress Report Ji-Cheng Zhao (Primary Contact), Xuenian Chen, Sheldon G. Shore The Ohio State University, Department of Materials Science and Engineering, 286 Watts Hall, 2041 College Road Columbus, OH 43210 Phone: (614) 292-9462 Email: zhao.199@osu.edu DOE Managers HQ: Ned Stetson Phone: (202) 586-9995 Email: Ned.Stetson@ee.doe.gov GO: Katie Randolph Phone: (720) 356-1759 Email: Katie.Randolph@go.doe.gov Contract Number: DE-FC3605GO15062 Project Start Date: January 1, 2005 Project End Date: August 31, 2011 (No-cost extension to December 31, 2012) Fiscal Year (FY) 2012 Objectives Develop a high-capacity lightweight hydride for * reversible vehicular hydrogen storage, capable of meeting or exceeding the 2010 DOE FreedomCAR

372

A unified view of coherent and incoherent dihydrogen exchange in transition metal hydrides by nuclear resonance and inelastic neutron scattering  

SciTech Connect

In this paper a unified view of coherent and incoherent dihydrogen exchange in transition metal hydrides by nuclear magnetic resonance (NMR) and inelastic neutron scattering (INS) is presented. It is shown that both exchange processes coexist i.e. do not transform into each other although they may dominate the spectra in different temperature ranges. This superposition is the consequence of the incorporation of the tunnel frequency J of the coherent process into the nuclear two-spin hamiltonian of hydrogen pairs which allows to treat the problem using the well known density matrix theory of NMR line-shapes developed by Alexander and Binsch. It is shown that this theory can also be used to predict the line-shapes of the rotational tunneling transitions observed in the INS spectra of transition metal dihydrogen complexes and that both NMR and INS spectra depend on similar parameters.

Limbach, H.H.; Ulrich, S.; Buntkowsky, G. [Freie Univ. Berlin (Germany). Inst. fuer Organische Chemie; Sabo-Etienne, S.; Chaudret, B. [Toulouse-3 Univ., 31 (France). Lab. de Chimie de Coordination du C.N.R.S.; Kubas, G.J.; Eckert, J. [Los Alamos National Lab., NM (United States)

1995-08-12T23:59:59.000Z

373

Exotic atoms and leptonic conservations  

DOE Green Energy (OSTI)

The major 1989 efforts have been on two aspects of experiments at TRIUMF. One effort was production of muonic hydrogen and muonic deuterium into a vacuum. We study rates relevant to muonic catalyzed fusion, and if there are found an adequate number of muons in the 2s state then we plan to measure precision energies. The second effort was to develop plans for kaonic atoms at the kaon factory. We also completed analyses from the experiments with pionic atoms at LAMPF.

Kunselman, R.

1990-01-01T23:59:59.000Z

374

Biogass Generator  

NLE Websites -- All DOE Office Websites (Extended Search)

Another internet tool by: Another internet tool by: Build Your Own Page 1 of 5 Teach...build...learn...renewable energy! Biogas Generator A Renewable Energy Project Kit The Pembina Institute What Is Biogas? Biogas is actually a mixture of gases, usually carbon dioxide and methane. It is produced by a few kinds of microorganisms, usually when air or oxygen is absent. (The absence of oxygen is called "anaerobic conditions.") Animals that eat a lot of plant material, particularly grazing animals such as cattle, produce large amounts of biogas. The biogas is produced not by the cow or elephant, but by billions of microor- ganisms living in its digestive system. Biogas also develops in bogs and at the bottom of lakes, where decaying organic matter builds up under wet and

375

Manipulation of Non-classical Atomic Spin States  

E-Print Network (OSTI)

We report successful manipulation of non-classical atomic spin states. We generate squeezed spin states by a spin quantum nondemolition measurement, and apply an off-resonant circularly-polarized light pulse to the atoms. By changing the pulse duration, we have clearly observed a rotation of anisotropic quantum noise distribution in good contrast with the case of manipulation of a coherent spin state where the quantum noise distribution is always isotropic. This is an important step for quantum state tomography, quantum swapping, and precision spectroscopic measurement.

Tetsushi Takano; Shin-Ichi-Ro Tanaka; Ryo Namiki; Yoshiro Takahashi

2009-09-13T23:59:59.000Z

376

Atomic Physics Division 1999 - Future Directions  

Science Conference Proceedings (OSTI)

... lying Rydberg states constitute a "frozen" Rydberg gas. ... of atom interactions in cold atomic gases and Bose ... or optical fields and tight confinement of ...

377

Cavity Quantum Electrodynamics with Ultracold Atoms.  

E-Print Network (OSTI)

??Die vorliegende Arbeit befasst sich mit der Wechselwirkung ultrakalter Atome mit der Mode eines optischen Resonators hoher Gu?te. Die Atome sind dabei in einem periodischen (more)

Habibian, Hessam

2013-01-01T23:59:59.000Z

378

Theoretical Atomic Physics code development II: ACE: Another collisional excitation code  

SciTech Connect

A new computer code for calculating collisional excitation data (collision strengths or cross sections) using a variety of models is described. The code uses data generated by the Cowan Atomic Structure code or CATS for the atomic structure. Collisional data are placed on a random access file and can be displayed in a variety of formats using the Theoretical Atomic Physics Code or TAPS. All of these codes are part of the Theoretical Atomic Physics code development effort at Los Alamos. 15 refs., 10 figs., 1 tab.

Clark, R.E.H.; Abdallah, J. Jr.; Csanak, G.; Mann, J.B.; Cowan, R.D.

1988-12-01T23:59:59.000Z

379

Sequential generation of matrix-product states in cavity QED  

Science Conference Proceedings (OSTI)

We study the sequential generation of entangled photonic and atomic multiqubit states in the realm of cavity QED. We extend the work of C. Schoen et al. [Phys. Rev. Lett. 95, 110503 (2005)], where it was shown that all states generated in a sequential manner can be classified efficiently in terms of matrix-product states. In particular, we consider two scenarios: photonic multiqubit states sequentially generated at the cavity output of a single-photon source and atomic multiqubit states generated by their sequential interaction with the same cavity mode.

Schoen, C. [Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BZ (United Kingdom); Hammerer, K. [Institute for Theoretical Physics, University of Innsbruck, 6020 Innsbruck (Austria); Wolf, M. M.; Cirac, J. I. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching (Germany); Solano, E. [Physics Department, ASC, and CeNS, Ludwig-Maximilians-Universitaet, Theresienstrasse 37, 80333 Munich (Germany); Seccion Fisica, Departamento de Ciencias, Pontificia Universidad Catolica del Peru, Apartado Postal 1761, Lima (Peru)

2007-03-15T23:59:59.000Z

380

Observation of relativistic antihydrogen atoms  

DOE Green Energy (OSTI)

An observation of relativistic antihydrogen atoms is reported in this dissertation. Experiment 862 at Fermi National Accelerator Laboratory observed antihydrogen atoms produced by the interaction of a circulating beam of high momentum (3 < p < 9 GeV/c) antiprotons and a jet of molecular hydrogen gas. Since the neutral antihydrogen does not bend in the antiproton source magnets, the detectors could be located far from the interaction point on a beamline tangent to the storage ring. The detection of the antihydrogen is accomplished by ionizing the atoms far from the interaction point. The positron is deflected by a magnetic spectrometer and detected, as are the back to back photons resulting from its annihilation. The antiproton travels a distance long enough for its momentum and time of flight to be measured accurately. A statistically significant sample of 101 antihydrogen atoms has been observed. A measurement of the cross section for {bar H}{sup 0} production is outlined within. The cross section corresponds to the process where a high momentum antiproton causes e{sup +} e{sup -} pair creation near a nucleus with the e{sup +} being captured by the antiproton. Antihydrogen is the first atom made exclusively of antimatter to be detected. The observation experiment's results are the first step towards an antihydrogen spectroscopy experiment which would measure the n = 2 Lamb shift and fine structure.

Blanford, Glenn DelFosse

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

The HERMES Polarized Atomic Beam Source  

Science Conference Proceedings (OSTI)

The atomic beam source (ABS) provides nuclear polarized hydrogen or deuterium atoms for the HERMES target at flow rates of about 6.5 ? 1016H?/s (hydrogen in two hyperfine substates) and 6.0 ? 1016D?/s (deuterium in three hyperfine substates). The degree of dissociation of 93% for H (95% for D) at the entrance of the storage cell and the nuclear polarization of around 0.97 (H) and 0.92 (D) have been found to be constant within a a couple of percent over the whole running period of the HERMES experiment. A new dissociator (MWD) based on a microwave discharge at 2.45 GHz has been developed and installed into the HERMES?ABS in 2000. Since the velocity distribution of the MWD differs from that of the RFD the intensity could be increased further with a modified sextupole magnet system. For this purpose the way for a new start generator for sextupole tracking calculations was opened. Monte?Carlo simulations were successfully used to describe the gas expansion between nozzle

A. Nass; HERMES target group

2003-01-01T23:59:59.000Z

382

DOE - Office of Legacy Management -- Shippingport Atomic Power Plant - PA  

Office of Legacy Management (LM)

Shippingport Atomic Power Plant - Shippingport Atomic Power Plant - PA 13 FUSRAP Considered Sites Site: SHIPPINGPORT ATOMIC POWER PLANT (PA.13 ) Eliminated from further consideration under FUSRAP. Designated Name: Not Designated Alternate Name: Duquesne Light Company PA.13-1 Location: 25 miles west of Pittsburgh in Beaver County , Shippingport , Pennsylvania PA.13-2 Evaluation Year: circa 1987 PA.13-3 Site Operations: First commercially operated nuclear power reactor. Joint project (Federal Government an Duquesne Light Company) to demonstrate pressurized water reactor technology and to generate electricity. Plant operated by Duquesne Light Company under supervision of the Office of the DOE Deputy Assistant Secretary for Naval Reactors -- 1957 to October 1982. PA.13-2 Site Disposition: Eliminated - No Authority. DOE chartered Major Project #118, Shippingport Station Decommissioning Project completed cleanup in 1989. PA.13-1

383

Manipulating mesoscopic multipartite entanglement with atom-light interfaces  

E-Print Network (OSTI)

Entanglement between two macroscopic atomic ensembles induced by measurement on an ancillary light system has proven to be a powerful method for engineering quantum memories and quantum state transfer. Here we investigate the feasibility of such methods for generation, manipulation and detection of genuine multipartite entanglement between mesoscopic atomic ensembles. Our results extend in a non trivial way the EPR entanglement between two macroscopic gas samples reported experimentally in [B. Julsgaard, A. Kozhekin, and E. Polzik, Nature {\\bf 413}, 400 (2001)]. We find that under realistic conditions, a second orthogonal light pulse interacting with the atomic samples, can modify and even reverse the entangling action of the first one leaving the samples in a separable state.

Stasi?ska, Julia; Paganelli, Simone; Birkl, Gerhard; Sanpera, Anna

2009-01-01T23:59:59.000Z

384

Manipulating mesoscopic multipartite entanglement with atom-light interfaces  

E-Print Network (OSTI)

Entanglement between two macroscopic atomic ensembles induced by measurement on an ancillary light system has proven to be a powerful method for engineering quantum memories and quantum state transfer. Here we investigate the feasibility of such methods for generation, manipulation and detection of genuine multipartite entanglement between mesoscopic atomic ensembles. Our results extend in a non trivial way the EPR entanglement between two macroscopic gas samples reported experimentally in [B. Julsgaard, A. Kozhekin, and E. Polzik, Nature {\\bf 413}, 400 (2001)]. We find that under realistic conditions, a second orthogonal light pulse interacting with the atomic samples, can modify and even reverse the entangling action of the first one leaving the samples in a separable state.

Julia Stasi?ska; Carles Rod; Simone Paganelli; Gerhard Birkl; Anna Sanpera

2009-07-24T23:59:59.000Z

385

SMALL OIL BURNER CONCEPTS BASED ON LOW PRESSURE AIR ATOMIZATION  

DOE Green Energy (OSTI)

The development of several novel oil burner applications based on low pressure air atomization is described. The atomizer used is a prefilming, airblast nozzle of the type commonly used in gas turbine combustion. The air pressure used can be as low as 1,300 Pa and such pressure can be easily achieved with a fan. Advantages over conventional, pressure-atomized nozzles include ability to operate at low input rates without very small passages and much lower fuel pressure requirements. The development of three specific applications is presented. The first two are domestic heating burners covering a capacity range 10 to 26 kW. The third application presented involves the use of this burner in an oil-fired thermophotovoltaic power generator system. Here the design firing rate is 2.9 kW and the system produces 500 watts of electric power.

BUTCHER,T.; CELEBI,Y.; WEI,G.; KAMATH,B.

2000-03-16T23:59:59.000Z

386

SCHROEDINGER'S CAT IN AN ATOMIC CAGE  

Science Conference Proceedings (OSTI)

... gov SCHROEDINGER'S CAT IN AN ATOMIC CAGE. They ... conditions. Schroedinger cat states are extremely fragile. Any ...

387

NIST: Atomic Spectros. - Spectral Continuum Radiation  

Science Conference Proceedings (OSTI)

Atomic Spectroscopy: home page. 21. Spectral Continuum Radiation. Hydrogenic Species. Precise quantum-mechanical ...

388

Executive Summaries for the Hydrogen Storage Materials Center of Excellence - Chemical Hydrogen Storage CoE, Hydrogen Sorption CoE, and Metal Hydride CoE  

NLE Websites -- All DOE Office Websites (Extended Search)

Executive Summaries Executive Summaries for the Hydrogen Storage Materials Centers of Excellence Chemical Hydrogen Storage CoE, Hydrogen Sorption CoE, and Metal Hydride CoE Period of Performance: 2005-2010 Fuel Cell Technologies Program Office of Energy Efficiency and Renewable Energy U. S. Department of Energy April 2012 2 3 Primary Authors: Chemical Hydrogen Storage (CHSCoE): Kevin Ott, Los Alamos National Laboratory Hydrogen Sorption (HSCoE): Lin Simpson, National Renewable Energy Laboratory Metal Hydride (MHCoE): Lennie Klebanoff, Sandia National Laboratory Contributors include members of the three Materials Centers of Excellence and the Department of Energy Hydrogen Storage Team in the Office of Energy Efficiency and Renewable Energy's Fuel Cell Technologies Program.

389

Cancer in atomic bomb survivors  

SciTech Connect

Radiation carcinogenesis was first noted in studies of individuals with occupational or therapeutic exposure to radiation. Data from long-term follow-up studies of atomic bomb survivors in Hiroshima and Nagasaki have greatly enhanced our knowledge of radiation carcinogenesis. This book presents current results obtained from epidemiological studies and pathological studies on cancer among atomic bomb survivors. It includes a description of the dosimetry system which is currently being revised. Although many of the details about radiation carcinogenesis remain unknown or uncertain, it is clear that the incidence of radiation-induced cancer among atomic bomb survivors continues unabated 40 years after exposure. Recent increases in occupational and environmental exposure to radiation together with the need for a thorough review of radiation protection standards have led to increased recognition of the importance of research on radiation carcinogenesis and risk assessment.

Shigematsu, I.; Kagan, A.

1986-01-01T23:59:59.000Z

390

Hot atom chemistry and radiopharmaceuticals  

Science Conference Proceedings (OSTI)

The chemical products made in a cyclotron target are a combined result of the chemical effects of the nuclear transformation that made the radioactive atom and the bulk radiolysis in the target. This review uses some well-known examples to understand how hot atom chemistry explains the primary products from a nuclear reaction and then how radiation chemistry is exploited to set up the optimal product for radiosynthesis. It also addresses the chemical effects of nuclear decay. There are important principles that are common to hot atom chemistry and radiopharmaceutical chemistry. Both emphasize short-lived radionuclides and manipulation of high specific activity nuclides. Furthermore, they both rely on radiochromatographic separation for identification of no-carrieradded products.

Krohn, Kenneth A.; Moerlein, Stephen M.; Link, Jeanne M.; Welch, Michael J. [University of Washington, Department of Radiology, Molecular Imaging Center, 1959 NE Pacific St., Box 356004, Seattle, WA 98195-6004 (United States); Washington University, Department of Radiology, Division of Radiological Sciences, 510 South Kingshighway, St. Louis, MO 63110 (United States); University of Washington, Department of Radiology, Molecular Imaging Center, 1959 NE Pacific St., Box 356004, Seattle, WA 98195-6004 (United States); Washington University, Department of Radiology, Division of Radiological Sciences, 510 South Kingshighway, St. Louis, MO 63110 (United States)

2012-12-19T23:59:59.000Z

391

Degeneracy Breaking of Hydrogen Atom  

E-Print Network (OSTI)

The three dimensional rotation group, SO(3), is a symmetry group of the normal hydrogen atom. Each reducible representation of this group can be associated with a degenerate energy level. If this atom is placed in an external magnetic field, the interaction between the orbital magnetic moment with this field will lead to a symmetry breaking where the symmetry group of the atom is a new group distinct from the SO(3) group. This phenomenon describes the normal Zeeman effect, where a degenerate energy level splits into several new energy levels. It is explicitly shown that each of the new energy levels can be associated with an irreducible representation of the new symmetry group.

Agung Trisetyarso; Pantur Silaban

2008-12-22T23:59:59.000Z

392

Supersonic coal water slurry fuel atomizer  

DOE Patents (OSTI)

A supersonic coal water slurry atomizer utilizing supersonic gas velocities to atomize coal water slurry is provided wherein atomization occurs externally of the atomizer. The atomizer has a central tube defining a coal water slurry passageway surrounded by an annular sleeve defining an annular passageway for gas. A converging/diverging section is provided for accelerating gas in the annular passageway to supersonic velocities. 3 figs.

Becker, F.E.; Smolensky, L.S.; Balsavich, J.

1989-11-01T23:59:59.000Z

393

Benefits of rapid solidification processing of modified LaNi{sub 5} alloys by high pressure gas atomization for battery applications  

DOE Green Energy (OSTI)

A high pressure gas atomization approach to rapid solidification has been employed to investigate simplified processing of Sn modified LaNi{sub 5} powders that can be used for advanced Ni/metal hydride (Ni/MH) batteries. The current industrial practice involves casting large ingots followed by annealing and grinding and utilizes a complex and costly alloy design. This investigation is an attempt to produce powders for battery cathode fabrication that can be used in an as-atomized condition without annealing or grinding. Both Ar and He atomization gas were tried to investigate rapid solidification effects. Sn alloy additions were tested to promote subambient pressure absorption/desorption of hydrogen at ambient temperature. The resulting fine, spherical powders were subject to microstructural analysis, hydrogen gas cycling, and annealing experiments to evaluate suitability for Ni/MH battery applications. The results demonstrate that a brief anneal is required to homogenize the as-solidified microstructure of both Ar and He atomized powders and to achieve a suitable hydrogen absorption behavior. The Sn addition also appears to suppress cracking during hydrogen gas phase cycling in particles smaller than about 25 {micro}m. These results suggest that direct powder processing of a LaNi{sub 5{minus}x}Sn{sub x} alloy has potential application in rechargeable Ni/MH batteries.

Anderson, I.E.; Pecharsky, V.K.; Ting, J. [Ames Lab., IA (United States); Witham, C.; Bowman, R.C. [California Inst. of Tech., Pasadena, CA (United States)

1997-12-31T23:59:59.000Z

394

Light-induced gauge fields for ultracold atoms  

E-Print Network (OSTI)

Gauge fields are central in our modern understanding of physics at all scales. At the highest energy scales known, the microscopic universe is governed by particles interacting with each other through the exchange of gauge bosons. At the largest length scales, our universe is ruled by gravity, whose gauge structure suggests the existence of a particle - the graviton - that mediates the gravitational force. At the mesoscopic scale, solid-state systems are subjected to gauge fields of different nature: materials can be immersed in external electromagnetic fields, but they can also feature emerging gauge fields in their low-energy description. In this review, we focus on another kind of gauge field: those engineered in systems of ultracold neutral atoms. In these setups, atoms are suitably coupled to laser fields that generate effective gauge potentials in their description. Neutral atoms "feeling" laser-induced gauge potentials can potentially mimic the behavior of an electron gas subjected to a magnetic field, but also, the interaction of elementary particles with non-Abelian gauge fields. Here, we review different realized and proposed techniques for creating gauge potentials - both Abelian and non-Abelian - in atomic systems and discuss their implication in the context of quantum simulation. While most of these setups concern the realization of background and classical gauge potentials, we conclude with more exotic proposals where these synthetic fields might be made dynamical, in view of simulating interacting gauge theories with cold atoms.

N. Goldman; G. Juzeliunas; P. Ohberg; I. B. Spielman

2013-08-29T23:59:59.000Z

395

Effect of Gaseous Impurities on Long-Term Thermal Cycling and Aging Properties of Complex Hydrides for Hydrogen Storage  

DOE Green Energy (OSTI)

This program was dedicated to understanding the effect of impurities on Long-Term Thermal Cycling and aging properties of Complex Hydrides for Hydrogen Storage. At the start of the program we found reversibility between Li2NH+LiH ? LiH+LiNH2 (yielding ~5.8 wt.%H capacity). Then we tested the effect of impurity in H2 gas by pressure cycling at 255oC; first with industrial gas containing ppm levels of O2 and H2O as major impurities. Both these impurities had a significant impact on the reversibility and decreased the capacity by 2.65 wt.%H. Further increase in number of cycles from 500 to 1100 showed only a 0.2 wt%H more weight loss, showing some capacity is still maintained after a significant number of cycles. The loss of capacity is attributed to the formation of ~55 wt% LiH and ~30% Li2O, as major contaminant phases, along with the hydride Li2NH phase; suggesting loss of nitrogen during cycling. The effect of 100 ppm H2O in H2 also showed a decrease of ~2.5 wt.%H (after 560 cycles), and 100ppm O2 in H2; a loss of ~4.1 wt.%. Methane impurity (100 ppm, 100cycles), showed a very small capacity loss of 0.9 wt.%H under similar conditions. However, when Li3N was pressure cycled with 100ppmN2-H2 there were beneficial effects were observed (255oC); the reversible capacity increased to 8.4wt.%H after 853 cycles. Furthermore, with 20 mol.%N2-H2 capacity increased to ~10 wt.%H after 516 cycles. We attribute this enhancement to the reaction of nitrogen with liquid lithium during cycling as the Gibbs free energy of formation of Li3N (?Go = -98.7 kJ/mol) is more negative than that of LiH (?Go = -50.3 kJ/mol). We propose that the mitigation of hydrogen capacity losses is due to the destabilization of the LiH phase that tends to accumulate during cycling. Also more Li2NH phase was found in the cycled product. Mixed Alanates (3LiNH2:Li3AlH6) showed that 7 wt% hydrogen desorbed under dynamic vacuum. Equilibrium experiments (maximum 12 bar H2) showed up to 4wt% hydrogen reversibly stored in the material after the first desorption. The activation energy was found to be 51 kJ/mol, as compared to 81 kJ/mol for pure lithium alanate. It is proposed that based on the data obtained and CALPHAD modeling that the improvement in cycling is due to the formation of pure lithium (liquid at 255oC), which is able to react with nitrogen specifically forming Li3N. The presence of nitrogen in the 80/20 molar mixtures in a hydride bed along with hydrogen causes Li to form Li3N rather than LiH, and subsequently regenerates the Li2NH phase and yields a ~10 wt.%H reversibly.

Chandra, Dhanesh (Primary Contact); Lamb, Joshua; Chien, Wen-Ming; Talekar, Anjali; and Pal, Narendra.

2011-03-28T23:59:59.000Z

396

Dynamical polarization in pionic atoms  

SciTech Connect

Dynamical nuclear polarization occurs in pionic atoms when a nuclear excitation of appropriate multipolarity is nearly degenerate with de-excitation of a pion atomic level. This phenomenon has been studied in several nuclei, one goal being to test the pion optical potential for pion atomic states normally ''hidden'' because of pion absorption. We find that, in addition to Coulomb mixing of the atomic and nuclear levels, strong interaction mixing and nuclear excitations above the lowest collective quadrupole mode are important for understanding the experimental results. All cases except /sup 110/Pd can then be understood. For /sup 110/Pd, additional nuclear structure information is needed to determine whether or not the conventional pion optical potential will suffice again. We discuss the sensitivity of dynamical polarization measurements to the parameters of the optical potential and to various aspects of nuclear structure. In particular, we find that pionic /sup 150/Sm provides a test of the interacting boson model and that the difference in neutron and proton radii predicted by Hartree-Fock calculations affects the mixing appreciably.

Dubach, J.F.; Moniz, E.J.; Nixon, G.D.

1979-08-01T23:59:59.000Z

397

Next Generation Light Source Workshops  

NLE Websites -- All DOE Office Websites (Extended Search)

Next Generation Light Source Workshops Next Generation Light Source Workshops A series of workshops will be held in late August with the goal of refining the scientific drivers for the facility and translating the scientific needs into the technical performance requirements. Feedback from these workshops will provide important input for advancing the design of the facility. Workshops are planned in the following areas Fundamental Atomic, Molecular, Optical Physics & Combustion Dynamics Mon. Aug. 20 - Tues. Aug 21, 2012 Physical Chemistry, Catalysis, & Photosynthesis Thurs. Aug. 23 - Fri. Aug 24, 2012 Quantum Materials, Magnetism & Spin Dynamics Mon. Aug. 27 - Tues. Aug 28, 2012 Materials & Bio-imaging at the Nanoscale Thurs. Aug. 30 - Fri. Aug 31, 2012 Further information is available on the workshop website:

398

First principles screening of destabilized metal hydrides for high capacity H2 storage using scandium (presentation had varying title: Accelerating Development of Destabilized Metal Hydrides for Hydrogen Storage Using First Principles Calculations)  

DOE Green Energy (OSTI)

Favorable thermodynamics are a prerequisite for practical H2 storage materials for vehicular applications. Destabilization of metal hydrides is a versatile route to finding materials that reversibly store large quantities of H2. First principles calculations have proven to be a useful tool for screening large numbers of potential destabilization reactions when tabulated thermodynamic data are unavailable. We have used first principles calculations to screen potential destabilization schemes that involve Sc-containing compounds. Our calculations use a two-stage strategy in which reactions are initially assessed based on their reaction enthalpy alone, followed by more detailed free energy calculations for promising reactions. Our calculations indicate that mixtures of ScH2 + 2LiBH4, which will release 8.9 wt.% H2 at completion and will have an equilibrium pressure of 1 bar at around 330 K, making this compound a promising target for experimental study. Along with thermodynamics, favorable kinetics are also of enormous importance for practical usage of these materials. Experiments would help identify possible kinetic barriers and modify them by developing suitable catalysts.

Alapati, S.; Johnson, J.K.; Sholl, D.S.; Dai, B. (Univ. of Pittsburgh, Pittsburgh, PA)--last author not shown on publication, only presentation

2007-10-31T23:59:59.000Z

399

Magneto-Optical Cooling of Atoms  

E-Print Network (OSTI)

We propose an alternative method to laser cooling. Our approach utilizes the extreme brightness of a supersonic atomic beam, and the adiabatic atomic coilgun to slow atoms in the beam or to bring them to rest. We show how internal-state optical pumping and stimulated optical transitions, combined with magnetic forces can be used to cool the translational motion of atoms. This approach does not rely on momentum transfer from photons to atoms, as in laser cooling. We predict that our method can surpass laser cooling in terms of flux of ultra-cold atoms and phase-space density, with lower required laser power and reduced complexity.

Raizen, Mark G; Rochester, Simon; Narevicius, Julia; Narevicius, Edvardas

2013-01-01T23:59:59.000Z

400

Atomic physics and non-equilibrium plasmas  

DOE Green Energy (OSTI)

Three lectures comprise the report. The lecture, Atomic Structure, is primarily theoretical and covers four topics: (1) Non-relativistic one-electron atom, (2) Relativistic one-electron atom, (3) Non-relativistic many-electron atom, and (4) Relativistic many-electron atom. The lecture, Radiative and Collisional Transitions, considers the problem of transitions between atomic states caused by interactions with radiation or other particles. The lecture, Ionization Balance: Spectral Line Shapes, discusses collisional and radiative transitions when ionization and recombination processes are included. 24 figs., 11 tabs.

Weisheit, J.C.

1986-04-25T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Frequency Synthesis for Atomic Standards  

Science Conference Proceedings (OSTI)

... A new generation of synthesizers includes digital control of the oscillators so that ... needed over a 25-year lifetime of normal aging; power from single ...

2010-10-05T23:59:59.000Z

402

UNITED STATES ATOMIC ENERGY COMMISSION  

Office of Legacy Management (LM)

I(S.0 -01: I(S.0 -01: SPECIAL NUCLEAR MATERIAL LlCEWSE Pursuant to the Atomic Energy Act of 1954 and Title 10, Code of Federal Regulations, Chapter 1, Part 70, "Special Nuclear Material Regulations," o. license is hereby issued authorizing the licensee to receive and possess the special nuclear material designated below; to use such special nuclear material for the purpose(s) and at the place(s) designated below; and to transfer such material to persons' authorized to receive it in accordance with the regulations in said Port. This license shall be deemed to contain the conditions specified in Section 70.32(a) of said regulations, and is subject to all applicable rules, regtdations, and orders of the Atomic Energy Commission now or hereafter in

403

Atomic vapor laser isotope separation  

SciTech Connect

Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements.

Stern, R.C.; Paisner, J.A.

1985-11-08T23:59:59.000Z

404

The Future of Atomic Energy  

DOE R&D Accomplishments (OSTI)

There is definitely a technical possibility that atomic power may gradually develop into one of the principal sources of useful power. If this expectation will prove correct, great advantages can be expected to come from the fact that the weight of the fuel is almost negligible. This feature may be particularly valuable for making power available to regions of difficult access and far from deposits of coal. It also may prove a great asset in mobile power units for example in a power plant for ship propulsion. On the negative side there are some technical limitations to be applicability of atomic power of which perhaps the most serious is the impossibility of constructing light power units; also there will be some peculiar difficulties in operating atomic plants, as for example the necessity of handling highly radioactive substances which will necessitate, at least for some considerable period, the use of specially skilled personnel for the operation. But the chief obstacle in the way of developing atomic power will be the difficulty of organizing a large scale industrial development in an internationally safe way. This presents actually problems much more difficult to solve than any of the technical developments that are necessary, It will require an unusual amount of statesmanship to balance properly the necessity of allaying the international suspicion that arises from withholding technical secrets against the obvious danger of dumping the details of the procedures for an extremely dangerous new method of warfare on a world that may not yet be prepared to renounce war. Furthermore, the proper balance should be found in the relatively short time that will elapse before the 'secrets' will naturally become open knowledge by rediscovery on part of the scientists and engineers of other countries.

Fermi, E.

1946-05-27T23:59:59.000Z

405

STAR FORMATION IN ATOMIC GAS  

SciTech Connect

Observations of nearby galaxies have firmly established, over a broad range of galactic environments and metallicities, that star formation occurs exclusively in the molecular phase of the interstellar medium (ISM). Theoretical models show that this association results from the correlation between chemical phase, shielding, and temperature. Interstellar gas converts from atomic to molecular only in regions that are well shielded from interstellar ultraviolet (UV) photons, and since UV photons are also the dominant source of interstellar heating, only in these shielded regions does the gas become cold enough to be subject to Jeans instability. However, while the equilibrium temperature and chemical state of interstellar gas are well correlated, the timescale required to reach chemical equilibrium is much longer than that required to reach thermal equilibrium, and both timescales are metallicity-dependent. Here I show that the difference in timescales implies that, at metallicities below a few percent of the solar value, well shielded gas will reach low temperatures and proceed to star formation before the bulk of it is able to convert from atomic to molecular. As a result, at extremely low metallicities, star formation will occur in a cold atomic phase of the ISM rather than a molecular phase. I calculate the observable consequences of this result for star formation in low-metallicity galaxies, and I discuss how some current numerical models for H{sub 2}-regulated star formation may need to be modified.

Krumholz, Mark R., E-mail: krumholz@ucolick.org [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)

2012-11-01T23:59:59.000Z

406

Role of atomic collisions in fusion  

SciTech Connect

Atomic physics issues have played a large role in controlled fusion research. A general discussion of the present role of atomic processes in both magnetic and inertial controlled fusion work is presented.

Post, D.E.

1982-04-01T23:59:59.000Z

407

Laser cooling and trapping of neutral atoms*  

Science Conference Proceedings (OSTI)

... 1 m/s, any gas in equilibrium (other than spin-polarized atomic hydro- ... lattice-trapped atoms, a physical picture with the simplicity and power of the ...

2010-08-23T23:59:59.000Z

408

Atomic vapor laser isotope separation process  

DOE Patents (OSTI)

A laser spectroscopy system is utilized in an atomic vapor laser isotope separation process. The system determines spectral components of an atomic vapor utilizing a laser heterodyne technique. 23 figs.

Wyeth, R.W.; Paisner, J.A.; Story, T.

1990-08-21T23:59:59.000Z

409

NIST Atomic Form Factors: Summary of uncertainties  

Science Conference Proceedings (OSTI)

... element. This "H92 - 3/5CL" value is 1.09 e/atom for uranium or 0.002 e/atom for Z = 6 (ie, 40 % of the dipole correction). ...

410

Towards a high-precision atomic gyroscope  

E-Print Network (OSTI)

In this thesis, I report on the design and construction of the Rubidium Atomic Gyroscope Experiment (RAGE) at Draper Lab.

Van Camp, Mackenzie A. (Mackenzie Anne)

2013-01-01T23:59:59.000Z

411

Argonne Chemical Sciences & Engineering - Institute for Atom...  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysis & Energy Conversion Electrochemical Energy Storage Nuclear & Environmental Processes National Security Institute for Atom-Efficient Chemical Transformations Center for...

412

NIST: Atomic Spectroscopy Group - Past News  

Science Conference Proceedings (OSTI)

... of Atomic, Molecular, and Optical Physics of the American Physical Society (DAMOP) in ... and Determination of Relative Nuclear Charge Radius.". ...

2013-06-06T23:59:59.000Z

413

Atomic Scale Deformation Mechanisms of Amorphous Polyethylene ...  

Science Conference Proceedings (OSTI)

Atomic Scale Deformation Mechanisms of Amorphous Polyethylene under Tensile Loading Atomistic Predictions of Age Hardening in Al-Cu Alloys.

414

NIST: Atomic Spectroscopy Group - John Curry  

Science Conference Proceedings (OSTI)

... chemical equilibrium and deviations from thermodynamic equilibrium. I am also interested in the acquisition and compilation of basic atomic data. ...

2011-02-09T23:59:59.000Z

415

NIST Atomic Physics Division 2000 - Technical Highlights  

Science Conference Proceedings (OSTI)

... Astrophysical Quantities," a handbook widely used ... and single-atom chemistry, where controlled ... understanding of fundamental processes occurring ...

416

Harmonic generation at high intensities  

Science Conference Proceedings (OSTI)

Atomic electrons subject to intense laser fields can absorb many photons, leading either to multiphoton ionization or the emission of a single, energetic photon which can be a high multiple of the laser frequency. The latter process, high-order harmonic generation, has been observed experimentally using a range of laser wavelengths and intensities over the past several years. Harmonic generation spectra have a generic form: a steep decline for the low order harmonics, followed by a plateau extending to high harmonic order, and finally an abrupt cutoff beyond which no harmonics are discernible. During the plateau the harmonic production is a very weak function of the process order. Harmonic generation is a promising source of coherent, tunable radiation in the XUV to soft X-ray range which could have a variety of scientific and possibly technological applications. Its conversion from an interesting multiphoton phenomenon to a useful laboratory radiation source requires a complete understanding of both its microscopic and macroscopic aspects. We present some recent results on the response of single atoms at intensities relevant to the short pulse experiments. The calculations employ time-dependent methods, which we briefly review in the next section. Following that we discuss the behavior of the harmonics as a function of laser intensity. Two features are notable: the slow scaling of the harmonic intensities with laser intensity, and the rapid variation in the phase of the individual harmonics with respect to harmonic order. We then give a simple empirical formula that predicts the extent of the plateau for a given ionization potential, wavelength and intensity.

Schafer, K.J.; Krause, J.L.; Kulander, K.C.

1993-06-01T23:59:59.000Z

417

Following Ostwald ripening in nanoalloys by high-resolution imaging with single-atom chemical sensitivity  

Science Conference Proceedings (OSTI)

Several studies have shown that substantial compositional changes can occur during the coarsening of bimetallic nanoparticles (CoPt, AuPd). To explain this phenomenon that could dramatically impacts all the technologically relevant properties of nanoalloys, we have exploited the sensitivity of the latest generation of electron microscope to prove that during the beam-induced coarsening of CoPt nanoparticles, the dynamic of atom exchanges between the particles is different for Co and Pt. By distinguishing the chemical nature of individual atoms of Co and Pt, while they are diffusing on a carbon film, we have clearly shown that Co atoms have a higher mobility than Pt atoms because of their higher evaporation rate from the particles. These atomic-scale observations bring the experimental evidence on the origin of the compositional changes in nanoalloys induced by Ostwald ripening mechanisms.

Alloyeau, D.; Nelayah, J.; Wang, G.; Ricolleau, C. [Laboratoire Materiaux et Phenomenes Quantiques, Universite Paris Diderot/CNRS, UMR 7162, Batiment Condorcet, 4 rue Elsa Morante, 75205 Paris Cedex 13 (France); Oikawa, T. [Laboratoire Materiaux et Phenomenes Quantiques, Universite Paris Diderot/CNRS, UMR 7162, Batiment Condorcet, 4 rue Elsa Morante, 75205 Paris Cedex 13 (France); JEOL Ltd, 1-2 Musashino 3-Chome, Akishima, Tokyo 196-8558 (Japan)

2012-09-17T23:59:59.000Z

418

Collisionally Induced Atomic Clock Shifts and Correlations  

E-Print Network (OSTI)

We develop a formalism to incorporate exchange symmetry considerations into the calculation of collisional frequency shifts and blackbody radiation effects for atomic clock transitions using a density matrix formalism. The formalism is developed for both fermionic and bosonic atomic clocks. Results for a finite temperature ${}^{87}$Sr ${}^1S_0$ ($F = 9/2$) atomic clock in a magic wavelength optical lattice are presented.

Y. B. Band; I. Osherov

2010-11-15T23:59:59.000Z

419

Single-atom and two-atom Ramsey interferometry with quantized fields  

SciTech Connect

Implications of field quantization on Ramsey interferometry are discussed and general conditions for the occurrence of interference are obtained. Interferences do not occur if the fields in two Ramsey zones have a precise number of photons. However, in this case we show how an analog of Hanbury-Brown Twiss photon-photon correlation interferometry can be used to discern a variety of interference effects as the two independent Ramsey zones get entangled by the passage of the first atom. Interferences are restored by working with fields at a single-photon level. Generation of entangled states including states such as vertical bar 2,0>+e{sup i{theta}} vertical bar 0,2> is discussed.

Agarwal, G.S.; Pathak, P.K. [Physical Research Laboratory, Navrangpura, Ahmedabad 380 009 (India); Scully, M.O. [Department of Physics, Texas A and M University, College Station, Texas 77843 (United States); Max-Planck Institut fuer Quantenoptik, Garching (Germany)

2003-04-01T23:59:59.000Z

420

Aerodynamic effects on fuel spray characteristics: Air-assist atomizer  

SciTech Connect

Results are presented on the internal structure of a kerosene fuel spray, generated with an air-assist type nozzle. Effects of atomization air flow rate and combustion air swirl on droplet transport processes have been investigated. Spatially-resolved measurements have been obtained on mean droplet size, number density and velocity, at different combustion air swirl and atomization air flow rates. An ensemble light scattering technique, based on measurement of the polarization ratio, and laser velocimetry have been used for these measurements. The results indicate that as atomization air flow rate increases, the spray becomes confined to a narrower spray angle; in addition, mean droplet size decreases and number density increases significantly along the spray centerline. Larger droplets are found generally on the spray boundary, and smaller ones near the spray centerline. In all cases, there is a gradual increase in mean droplet size along the spray centerline with axial distance. Under burning conditions the flame plume becomes short and intense, with fewer droplets penetrating through the flame envelope. Combustion air swirl and atomization air have a significant effect on the transport of droplets and on combustion characteristics of spray flames. 20 refs., 9 figs.

Presser, C.; Semerjian, H.G.; Gupta, A.K.

1988-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

General Atomics (GA) Fusion News: A New Spin on Understanding...  

NLE Websites -- All DOE Office Websites (Extended Search)

General Atomics (GA) Fusion News: A New Spin on Understanding Plasma Confinement American Fusion News Category: General Atomics (GA) Link: General Atomics (GA) Fusion News: A New...

422

Pages that link to "Atomic City, Idaho" | Open Energy Information  

Open Energy Info (EERE)

Share this page on Facebook icon Twitter icon Pages that link to "Atomic City, Idaho" Atomic City, Idaho Jump to: navigation, search What links here Page: Atomic City,...

423

Chapter 2 Suggested Problems: Final Answer Key Atomic mass: mass of an individual atom  

E-Print Network (OSTI)

Chapter 2 Suggested Problems: Final Answer Key 2.1 Atomic mass: mass of an individual atom Atomic;Chapter 3 Suggested Problems: Final Answer Key 3.1 Atomic Structure: relates the # of protons and neutrons of intercepts 2 2 1 Reduction not necessary Enclosure (221) #12;Chapter 12 Suggested Problems: Final Answer Key

Grunlan, Melissa A.

424

Stability of a superconductive atom chip with persistent current  

SciTech Connect

The lifetime of {sup 87}Rb atoms trapped in a z wire trap generated by a closed-circuit superconductive current on a MgB{sub 2} strip is measured as a function of the distance between the atom and the strip. The lifetime is found to be longer than 10 s at a distance of 40 {mu}m. This value is an order of magnitude longer than the lifetime of a trap generated by a normal current at the same distance. However, it is many orders of magnitude shorter than the theoretical decay rate induced by the spin-flip transition caused by the fluctuation of the current. This shows that for a type-II superconductor the dominant trap loss mechanism is not the spin-flip transition caused by noise as with a normal current atom trap. An analysis of our measurement suggests that magnetic field distortion resulting from flux penetration into the superconductor leads to much faster decay.

Hufnagel, Christoph; Mukai, Tetsuya [NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198 (Japan); CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 (Japan); Shimizu, Fujio [NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198 (Japan); CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 (Japan); Institute for Laser Science, University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 113-8585 (Japan)

2009-05-15T23:59:59.000Z

425

CERTIFICATION DOCKET WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT  

Office of Legacy Management (LM)

WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT EAST PITTSBURGH PLANT FOREST HILLS PITTSBURGH, PENNSYLVANIA Department of Energy Office of Nuclear Energy Office of Terminal Waste Disposal and Remedial Action Division of Remedial Action Projects ..-.. --__- _".-.-l--_--l -_._ _- --- ~~~. . ..~ CONTENTS Page - - I NTRODUCTI ON 1 Purpose 1 Docket Contents 1 Exhibit I: Summary of Activities at Westinghouse Atomic Power Development Plant, East Pittsburgh Plant, Forest Hills, Pittsburgh, Pennsylvania I-l Exhibit II: Documents Supporting the Certification of Westinghouse Atomic Power Development Plant, East Pittsburgh Plant, Forest Hills, Pittsburgh, Pennsylvania iii II-1 . . .- .__.^ I ^_... _.-__^-____-. - CERTIFICATION DOCKET WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT

426

Princeton Plasma Physics Lab - General Atomics (GA)  

NLE Websites -- All DOE Office Websites (Extended Search)

general-atomics-ga General general-atomics-ga General Atomics en The Scorpion's Strategy: "Catch and Subdue" http://www.pppl.gov/node/1132

American Fusion News Category: 
atomics-ga">General Atomics (GA)
427

The Atomic Energy Commission By Alice Buck  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Atomic Energy Atomic Energy Commission By Alice Buck July 1983 U.S. Department of Energy Office of Management Office of the Executive Secretariat Office of History and Heritage Resources 1 Introduction Almost a year after World War II ended, Congress established the United States Atomic Energy Commission to foster and control the peacetime development of atomic science and technology. Reflecting America's postwar optimism, Congress declared that atomic energy should be employed not only in the Nation's defense, but also to promote world peace, improve the public welfare, and strengthen free competition in private

428

Precision spectroscopy of the helium atom.  

SciTech Connect

Persistent efforts in both theory and experiment have yielded increasingly precise understanding of the helium atom. Because of its simplicity, the helium atom has long been a testing ground for relativistic and quantum electrodynamic effects in few-body atomic systems theoretically and experimentally. Comparison between theory and experiment of the helium spectroscopy in 1s2p{sup 3}P{sub J} can potentially extract a very precise value of the fine structure constant a. The helium atom can also be used to explore exotic nuclear structures. In this paper, we provide a brief review of the recent advances in precision calculations and measurements of the helium atom.

Hu, S.-M.; Lu, Z.-T.; Yan, Z.-C.; Physics; Univ. of Science and Technology of China; Univ. of Chicago; Univ. of New Brunswick

2009-06-01T23:59:59.000Z

429

Next Generation Radioisotope Generators | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

» Next Generation Radioisotope Generators » Next Generation Radioisotope Generators Next Generation Radioisotope Generators Advanced Stirling Radioisotope Generator (ASRG) - The ASRG is currently being developed as a high-efficiency RPS technology to support future space missions on the Martian surface or in the vacuum of space. This system uses Stirling convertors, which have moving parts to mechanically convert heat to electricity. This power conversion system, if successfully deployed, will reduce the weight of each RPS and the amount of Pu-238 needed per mission. A HISTORY OF MISSION SUCCESSES For over fifty years, the Department of Energy has enabled space exploration on 27 missions by providing safe reliable radioistope power systems and radioisotope heater units for NASA, Navy and Air Force.

430

Manhattan Project: Atomic Discoveries, 1890s-1939  

Office of Scientific and Technical Information (OSTI)

Excerpt from the comic book "Adventures Inside the Atom." Click on this image or visit the "Library" to view the whole comic book. ATOMIC DISCOVERIES Excerpt from the comic book "Adventures Inside the Atom." Click on this image or visit the "Library" to view the whole comic book. ATOMIC DISCOVERIES (1890s-1939) Events A Miniature Solar System, 1890s-1919 Exploring the Atom, 1919-1932 Atomic Bombardment, 1932-1938 The Discovery of Fission, 1938-1939 Fission Comes to America, 1939 Philosophers of Ancient Greece reasoned that all matter in the universe must be composed of fundamental, unchangeable, and indivisible objects, which they called "atoma" ("ατoµα"). The exact nature of these atoms remained elusive, however, despite centuries of attempts by alchemists to create a "philosopher's stone" that could transmute atoms of lead to gold, prove the Greeks wrong, and make its inventors Modern model of an atom very rich. It was only in the late 1890s and the early twentieth-century that this view of a solid atom, bouncing around the universe like a billiard ball, was replaced by an atom that resembled more a miniature solar system, its electrons orbiting around a small nucleus. Explorations into the nature of the atom from 1919 to 1932 confirmed this new model, especially with Ernest Rutherford's 1919 success in finally transmuting an atom of one substance into another and with James Chadwick's 1932 discovery of the elusive final basic particle of the atom, the neutron. From 1932 to 1938, scientists around the world learned a great deal more about atoms, primarily by bombarding the nuclei of atoms and using a variety of particle accelerators. In 1938, word came from Berlin of the most startling result of them all: the nucleus of an atom could actually be split in two, or "fissioned." This breakthrough was quickly confirmed in the United States and elsewhere. According to the theories of Albert Einstein, the fission of an atom should result in a release of energy. An "atomic bomb" was now no longer just science fiction -- it was a distinct possibility.

431

Definition: Thermoelectric power generation | Open Energy Information  

Open Energy Info (EERE)

Thermoelectric power generation Thermoelectric power generation Jump to: navigation, search Dictionary.png Thermoelectric power generation The conversion of thermal energy into electrical energy. Thermoelectric generation relies on a fuel source (e.g. fossil, nuclear, biomass, geothermal, or solar) to heat a fluid to drive a turbine[1] View on Wikipedia Wikipedia Definition The thermoelectric effect is the direct conversion of temperature differences to electric voltage and vice-versa. A thermoelectric device creates voltage when there is a different temperature on each side. Conversely, when a voltage is applied to it, it creates a temperature difference. At the atomic scale, an applied temperature gradient causes charge carriers in the material to diffuse from the hot side to the cold

432

Dynamical density functional theory for dense atomic liquids  

E-Print Network (OSTI)

Starting from Newton's equations of motion, we derive a dynamical density functional theory (DDFT) applicable to atomic liquids. The theory has the feature that it requires as input the Helmholtz free energy functional from equilibrium density functional theory. This means that, given a reliable equilibrium free energy functional, the correct equilibrium fluid density profile is guaranteed. We show that when the isothermal compressibility is small, the DDFT generates the correct value for the speed of sound in a dense liquid. We also interpret the theory as a dynamical equation for a coarse grained fluid density and show that the theory can be used (making further approximations) to derive the standard mode coupling theory that is used to describe the glass transition. The present theory should provide a useful starting point for describing the dynamics of inhomogeneous atomic fluids.

A. J. Archer

2006-04-25T23:59:59.000Z

433

Hydrogen Atom in Relativistic Motion  

E-Print Network (OSTI)

The Lorentz contraction of bound states in field theory is often appealed to in qualitative descriptions of high energy particle collisions. Surprisingly, the contraction has not been demonstrated explicitly even in simple cases such as the hydrogen atom. It requires a calculation of wave functions evaluated at equal (ordinary) time for bound states in motion. Such wave functions are not obtained by kinematic boosts from the rest frame. Starting from the exact Bethe-Salpeter equation we derive the equal-time wave function of a fermion-antifermion bound state in QED, i.e., positronium or the hydrogen atom, in any frame to leading order in alpha. We show explicitly that the bound state energy transforms as the fourth component of a vector and that the wave function of the fermion-antifermion Fock state contracts as expected. Transverse photon exchange contributes at leading order to the binding energy of the bound state in motion. We study the general features of the corresponding fermion-antifermion-photon Fock states, and show that they do not transform by simply contracting. We verify that the wave function reduces to the light-front one in the infinite momentum frame.

M. Jarvinen

2004-11-16T23:59:59.000Z

434

Laser sustained discharge nozzle apparatus for the production of an intense beam of high kinetic energy atomic species  

DOE Patents (OSTI)

Laser sustained discharge apparatus for the production of intense beams of high kinetic energy atomic species. A portion of the plasma resulting from a laser sustained continuous optical discharge which generates energetic atomic species from a gaseous source thereof is expanded through a nozzle into a region of low pressure. The expanded plasma contains a significant concentration of the high kinetic energy atomic species which may be used to investigate the interaction of surfaces therewith. In particular, O-atoms having velocities in excess of 3.5 km/s can be generated for the purpose of studying their interaction with materials in order to develop protective materials for spacecraft which are exposed to such energetic O-atoms during operation in low earth orbit.

Cross, Jon B. (Santa Fe, NM); Cremers, David A. (Los Alamos, NM)

1988-01-01T23:59:59.000Z

435

Laser sustained discharge nozzle apparatus for the production of an intense beam of high kinetic energy atomic species  

DOE Patents (OSTI)

Laser sustained discharge apparatus for the production of intense beams of high kinetic energy atomic species is described. A portion of the plasma resulting from a laser sustained continuous optical discharge which generates energetic atomic species from a gaseous source thereof is expanded through a nozzle into a region of low pressure. The expanded plasma contains a significant concentration of the high kinetic energy atomic species which may be used to investigate the interaction of surfaces therewith. In particular, O-atoms having velocities in excess of 3.5 km/s can be generated for the purpose of studying their interaction with materials in order to develop protective materials for spacecraft which are exposed to such energetic O-atoms during operation in low earth orbit.

Cross, J.B.; Cremers, D.A.

1986-01-10T23:59:59.000Z

436

High-Resolution Imaging and Optical Control of Bose-Einstein Condensates in an Atom Chip Magnetic Trap  

E-Print Network (OSTI)

A high-resolution projection and imaging system for ultracold atoms is implemented using a compound silicon and glass atom chip. The atom chip is metalized to enable magnetic trapping while glass regions enable high numerical aperture optical access to atoms residing in the magnetic trap about 100 microns below the chip surface. The atom chip serves as a wall of the vacuum system, which enables the use of commercial microscope components for projection and imaging. Holographically generated light patterns are used to optically slice a cigar-shaped magnetic trap into separate regions; this has been used to simultaneously generate up to four Bose-condensates. Using fluorescence techniques we have demonstrated in-trap imaging resolution down to 2.5 microns

Evan A. Salim; Seth C. Caliga; Jonathan B. Pfeiffer; Dana Z. Anderson

2012-08-24T23:59:59.000Z

437

Hydrogen Generation by Electrolysis  

NLE Websites -- All DOE Office Websites (Extended Search)

Better Engineered Solutions. Better Engineered Solutions. What Listening Generates. Better Engineered Solutions. What Listening Generates. Hydrogen Generation by Electrolysis September 2004 Steve Cohen Hydrogen Generation by Electrolysis September 2004 Steve Cohen NREL H 2 Electrolysis - Utility Integration Workshop NREL H 2 Electrolysis - Utility Integration Workshop 2 Hydrogen Generation by Electrolysis Hydrogen Generation by Electrolysis  Intro to Teledyne Energy Systems  H 2 Generator Basics & Major Subsystems  H 2 Generating & Storage System Overview  Electrolysis System Efficiency & Economics  Focus for Attaining DOE H 2 Production Cost Goals 3 Teledyne Energy Systems Locations - ISO 9001 Teledyne Energy Systems Locations - ISO 9001 Hunt Valley, Maryland  State-of-the-art thermoelectric,

438

Siemens Power Generation, Inc.  

NLE Websites -- All DOE Office Websites (Extended Search)

Presented at the 2005 Pittsburgh Coal Conference Siemens Power Generation, Inc. Page 1 of 10 Siemens Power Generation, Inc., All Rights Reserved Development of a Catalytic...

439

Industrial Waste Generation  

NLE Websites -- All DOE Office Websites (Extended Search)

9) Page 2 of 7 Industrial Waste Generation Work with Engineered Nanomaterials Power Consumption Historical Contamination (groundwater, soil) Hazardous Waste Generation Atmospheric...

440

Improved method for the production of atomic ion species from plasma ion sources  

DOE Patents (OSTI)

A technique to enhance the yield of neutral atomic and ionic species (H{sup +}, D{sup +}, O{sup +}, N{sup +}, etc.) from plasmas. The technique involves the addition of catalyzing agents to the ion discharge. Effective catalysts include H{sub 2}O, O{sub 2}, and SF{sub 6}, among others, with the most effective being water (H{sub 2}O). This technique has been developed at Argonne National Laboratory, where microwave produced beams consisting essentially of 100% atomic neutral species (H) have been generated, and ion beams of close to 100% purity have been generated.

Spence, D.; Lykke, K.

1996-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

CTrigger: Exposing Atomicity Violation Bugs from Their Hiding Places  

E-Print Network (OSTI)

of the two molecules, broken down by atom, helps the user to understand which atoms of the drug and protein

Lu, Shan

442

Atomic force microscope: Enhanced sensitivity  

SciTech Connect

Atomic force microscopes (AFMs) are a recent development representing the state of the art in measuring ultrafine surface features. Applications are found in such fields of research as biology, microfabrication, material studies, and surface chemistry. Fiber-optic interferometer techniques developed at LLNL offer the potential of improving the vertical resolution of these instruments by up to 2 orders of magnitude. We are attempting to replace the current AFM measurement scheme, which consists of an optical beam deflection approach, with our fiber-optic interferometer scheme, a much more sensitive displacement measurement technique. In performing this research, we hope to accomplish two important goals; (1) to enhance the sensitivity of the AFM, and (2) to achieve important improvements in our fiber-optic interferometer technology.

Davis, D.T.

1995-06-01T23:59:59.000Z

443

Hyperbaric hydrothermal atomic force microscope  

SciTech Connect

A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

Knauss, Kevin G. (Livermore, CA); Boro, Carl O. (Milpitas, CA); Higgins, Steven R. (Laramie, WY); Eggleston, Carrick M. (Laramie, WY)

2002-01-01T23:59:59.000Z

444

Cavity cooling of a single atom  

E-Print Network (OSTI)

All conventional methods to laser-cool atoms rely on repeated cycles of optical pumping and spontaneous emission of a photon by the atom. Spontaneous emission in a random direction is the dissipative mechanism required to remove entropy from the atom. However, alternative cooling methods have been proposed for a single atom strongly coupled to a high-finesse cavity; the role of spontaneous emission is replaced by the escape of a photon from the cavity. Application of such cooling schemes would improve the performance of atom cavity systems for quantum information processing. Furthermore, as cavity cooling does not rely on spontaneous emission, it can be applied to systems that cannot be laser-cooled by conventional methods; these include molecules (which do not have a closed transition) and collective excitations of Bose condensates, which are destroyed by randomly directed recoil kicks. Here we demonstrate cavity cooling of single rubidium atoms stored in an intracavity dipole trap. The cooling mechanism res...

Maunz, P; Schuster, I; Syassen, N; Pinkse, P W H; Rempe, G

2004-01-01T23:59:59.000Z

445

The Harnessed Atom | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Services » The Harnessed Atom Services » The Harnessed Atom The Harnessed Atom The Harnessed Atom The Harnessed Atom is a new middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on nuclear science and energy. It offers teachers accurate, unbiased, and up-to-date information on the roles that energy and nuclear science play in our lives. The curriculum includes essential principles and fundamental concepts of energy science. This teacher's kit is an updated and expanded edition of the acclaimed 1985 Harnessed Atom curriculum from the U.S. Department of Energy. It was developed with extensive input from classroom teachers across the country in pilot test reviews and workshops, as well as technical reviews from scientists and experts at universities, professional societies, and

446

Generation of fan-states of radiation field in a cavity  

E-Print Network (OSTI)

A scheme of generating recently introduced fan-states | \\alpha, 2k>_F (\\alpha is complex, k=1,2,3,...) is proposed basing on a \\Lambda-type atom-cavity field interaction. We show that with suitable atomic preparations and measurements a passage of a sequence of N atoms through a cavity may transform an initial field coherent state | \\alpha> to a fan-state | \\alpha, 2k>_F with k=2^{N-2}.

Nguyen Ba An; Truong Minh Duc

2001-11-30T23:59:59.000Z

447

Theory of atomic motion in resonant radiation  

SciTech Connect

Atomic motion in resonant and near resonant electromagnetic radiation is investigated theoretically. The exposition begins with a study of atomic motion in a resonant standing light wave, with a view toward isotope separation by selective photodeflection, and proceeds to the investigation of more general problems of atomic motion in resonant radiation. The body of the work consists of six chapters, each of which was prepared as a manuscript for publication in the open literature.

Cook, R.J.

1980-03-01T23:59:59.000Z

448

Method for enhanced atomization of liquids  

DOE Patents (OSTI)

In a process for atomizing a slurry or liquid process stream in which a slurry or liquid is passed through a nozzle to provide a primary atomized process stream, an improvement which comprises subjecting the liquid or slurry process stream to microwave energy as the liquid or slurry process stream exits the nozzle, wherein sufficient microwave heating is provided to flash vaporize the primary atomized process stream.

Thompson, Richard E. (27121 Puerta del Oro, Mission Viejo, CA 92691); White, Jerome R. (44755 Wyandotte, Hemet, CA 92544)

1993-01-01T23:59:59.000Z

449

Using Quantum Coherence to Enhance Gain in Atomic Physics  

E-Print Network (OSTI)

Quantum coherence and interference effects in atomic and molecular physics has been extensively studied due to intriguing counterintuitive physics and potential important applications. Here we present one such application of using quantum coherence to generate and enhance gain in extreme ultra-violet(XUV)(@58.4nm in Helium) and infra-red(@794.76nm in Rubidium) regime of electromagnetic radiation. We show that using moderate external coherent drive, a substantial enhancement in the energy of the lasing pulse can be achieved under optimal conditions. We also discuss the role of coherence. The present paper is intended to be pedagogical on this subject of coherence-enhanced lasing.

Pankaj K. Jha

2013-01-28T23:59:59.000Z

450

NIST Handbook of Basic Atomic Spectroscopic Data  

Science Conference Proceedings (OSTI)

... The compilation includes data for the neutral and singly-ionized atoms of all elements hydrogen through einsteinium (Z = 1-99). ... Access the Data. ...

2011-12-09T23:59:59.000Z

451

NIST Atomic Form Factors: Concerns with standard ...  

Science Conference Proceedings (OSTI)

... pair production cross-section in the nuclear field (? n ... upon angle (in f 0 ) and energy (in f ... All general theories make the isolated atom approximation ...

452

A History of the Atomic Energy Commission  

Energy.gov (U.S. Department of Energy (DOE))

A History of the Atomic Energy Commission - written by Alice L. BuckWashington, D.C.: U.S. Department of Energy, July 1983.41 pp.

453

Atom Probe Tomography and Transmission Electron Microscopy ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Atom probe tomography (APT) and analytical transmission .... of a Leaking Type 316 Socket Weld in a Boron Injection Tank Sampling Line.

454

Prospects for Atomic-Scale Tomography  

Science Conference Proceedings (OSTI)

Abstract Scope, Atomic-scale tomography (AST) may be defined as any technique that ... Initial Age Hardening and Nanostructural Evolution in a Cu-Ni-P Alloy.

455

Atom Manipulation with the Scanning Tunneling Microscope  

Science Conference Proceedings (OSTI)

... nanostructure from an unknown random collection of atoms without human intervention. ... a set of extensible rules, and allows for error correction. ...

2013-04-26T23:59:59.000Z

456

Materials Synthesis from Atoms to Systems | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

to produce unique single crystals and epitaxial structures that are deposited with atomic-level precision is critical for many applications, such as thermoelectrics,...

457

NIST Unveils Chip-Scale Atomic Clock  

Science Conference Proceedings (OSTI)

... 100 times smaller than any other atomic clockhas ... precise timekeeping in portable, battery-powered devices ... to be operated on batteries) and are ...