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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

automated hydride generation-cryotrapping-atomic: Topics by E...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Mohammad 3 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

2

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

3

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

4

E-Print Network 3.0 - antimony hydrides Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and Sb(V) were the only hydride-forming species found... WATERS BY HYDRIDE GENERATION ATOMIC ABSORPTION SPECTROMETRY Water-Resources Investigations Report 03... Prior to the...

5

Hydride generation from the Exide load-leveling cells  

SciTech Connect (OSTI)

Stibine and arsine evolution from lead-acid cells in a 36-kWh Exide load-leveling module was measured as this module approached 1900 cycles of operation. A gas-collection apparatus enabled us to determine the maximum and average rates for evolution of both toxic hydrides. Hydride generation began once the cell voltage exceeded 2.4 V. The maximum rate for arsine occurred just above 2.5 V and consistently preceded the peak rate for stibine for each sampled cell. The average rates of hydride generation were found to be 175 ..mu..g/min for stibine and 12.6 ..mu..g/min for arsine. The former rate proved to be the critical value in determining safe ventilation requirements for cell off-gases. The minimum airflow requirement was calculated to be 340 L/min per cell. Projections for a hypothetical 1-MWh Exide battery without an abatement system indicated that the normal ventilation capacity in the Battery Energy Storage Test facility provides nearly five times the airflow needed for safe hydride removal.

Marr, J.J.; Smaga, J.A.

1987-05-01T23:59:59.000Z

6

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

SciTech Connect (OSTI)

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 night—when the sun is not out—to 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. PNNL’s 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- 800°C). A high-temperature tank in PNNL’s 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 PNNL’s 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

7

E-Print Network 3.0 - arsenic hydrides Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

(2002) 1080-703902.50 Summary: for arsenic species using hydride generation and atomic absorption spectroscopy. The detec- tion limit for As... by ASP Estimation of...

8

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

9

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

SciTech Connect (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

10

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

SciTech Connect (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 team’s 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

11

Proposed Virtual Center for Excellence for Metal Hydride Development  

Broader source: Energy.gov (indexed) [DOE]

& Engineering Sciences Center Atoms to Continuum Proposed Virtual Center of Excellence Proposed Virtual Center of Excellence for Metal Hydride Development for Metal Hydride...

12

Atomic-Scale Chemical, Physical and Electronic Properties of the Subsurface Hydride of Palladium  

SciTech Connect (OSTI)

We employed low-temperature, extreme-high vacuum scanning tunneling microscopy (STM) to investigate the roles of subsurface hydride (H) and deuteride (D) in the surface reconstruction and surface reactivity of Pd{110}. Specifically, we gained the ability to tailor the surface structure of Pd{110} both by preparation method and by deposition of deuterium from the gas phase. We observed thiophene at low coverage on Pd{110} to determine its adsorption orientation and electronic structure through scanning tunneling spectroscopy (STS) – namely, conductance spectroscopy and differential conductance imaging. We developed the methods necessary to coadsorb D adatoms with thiophene molecules, and to induce the reaction of individual molecules with predefined subsurface H or D features. In the case of Pd{110}, we found a much more pronounced effect from subsurface D, as it is influenced by the surface directionality. These experiments facilitate an understanding of the role of surface and subsurface H and D in heterogeneous catalytic processes, specifically in the hydrodesulfuization (HDS) of thiophene, an important and ubiquitous component found to be detrimental to petroleum refining.

Weiss, Paul

2014-01-20T23:59:59.000Z

13

Photoelectron spectroscopy of boron aluminum hydride cluster anions  

SciTech Connect (OSTI)

Boron aluminum hydride clusters are studied through a synergetic combination of anion photoelectron spectroscopy and density functional theory based calculations. Boron aluminum hydride cluster anions, B{sub x}Al{sub y}H{sub z}{sup ?}, were generated in a pulsed arc cluster ionization source and identified by time-of-flight mass spectrometry. After mass selection, their photoelectron spectra were measured by a magnetic bottle-type electron energy analyzer. The resultant photoelectron spectra as well as calculations on a selected series of stoichiometries reveal significant geometrical changes upon substitution of aluminum atoms by boron atoms.

Wang, Haopeng; Zhang, Xinxing; Ko, Yeon Jae; Gantefoer, Gerd; Bowen, Kit H., E-mail: kbowen@jhu.edu, E-mail: kiran@mcneese.edu [Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Li, Xiang [Center for Space Science and Technology, University of Maryland–Baltimore County, Baltimore, Maryland 21250 (United States)] [Center for Space Science and Technology, University of Maryland–Baltimore County, Baltimore, Maryland 21250 (United States); Kiran, Boggavarapu, E-mail: kbowen@jhu.edu, E-mail: kiran@mcneese.edu [Department of Chemistry and Physics, McNeese State University, Lake Charles, Louisiana 70609 (United States)] [Department of Chemistry and Physics, McNeese State University, Lake Charles, Louisiana 70609 (United States); Kandalam, Anil K. [Department of Physics, West Chester University, West Chester, Pennsylvania 19383 (United States)] [Department of Physics, West Chester University, West Chester, Pennsylvania 19383 (United States)

2014-04-28T23:59:59.000Z

14

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

15

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

16

Constituting Atoms of a $?$ Algebra via Its Generator  

E-Print Network [OSTI]

To constitute atoms of a $\\sigma$ algebra is not a easy task due to the large number of its elements. However, determining them via generators seems a feasible and simple way since most $\\sigma$ algebras are generated by their smaller proper subsets. Precisely, under some conditions each atom of a $\\sigma$ algebra equals the intersection of the elements containing a point of the atom in the generator. In this paper, a very weak sufficient condition for determining atoms by the generator is presented. The condition, though not being a necessary one, is shown to be almost the weakest one in the sense that it can hardly be improved.

Jinshan Zhang

2007-11-15T23:59:59.000Z

17

Optically generated gauge potentials and their effects in cold atoms.  

E-Print Network [OSTI]

??Recent theoretical studies show the possibility of generating optical gauge potentials in neutral atoms using laser beams carrying orbital angular momentum. This is interesting not… (more)

Song, Jianjun

2008-01-01T23:59:59.000Z

18

Generation of atomic entangled states using linear optics  

E-Print Network [OSTI]

In this paper, we propose a novel scheme that can generate two-atom maximally entangled states from pure product states and mixed states using linear optics. Because the scheme can generate pure maximally entangled states from mixed states, we denote it as purification-like generation scheme.

Zhuo-Liang Cao; Ming Yang

2003-11-13T23:59:59.000Z

19

atomic power generation: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

a squeezed atom laser is to use Queensland, University of 420 A Silicon-Based Micro Gas Turbine Engine for Power Generation CERN Preprints Summary: This paper reports on our...

20

E-Print Network 3.0 - atom reaction product Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and product electronic states. As for hydrogen atom and hydride transfer reactions, the nuclear quantum... -4235020301 17.50+.500 33 Comparison of Hydride, Hydrogen Atom,...

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

Advanced Hydride Laboratory  

SciTech Connect (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

22

Advanced Hydride Laboratory  

SciTech Connect (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.

1989-12-31T23:59:59.000Z

23

Metal Hydrides - Science Needs  

Broader source: Energy.gov (indexed) [DOE]

with traditions in metal hydride research Metal and Ceramic Sciences Condensed Matter Physics Materials Chemistry Chemical and Biological Sciences Located on campus of Tier...

24

E-Print Network 3.0 - atomic beams generated Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

beams generated Search Powered by Explorit Topic List Advanced Search Sample search results for: atomic beams generated Page: << < 1 2 3 4 5 > >> 1 Superradiant Rayleigh scattering...

25

1/28/2014 CFCAM Workshop 2014 1 How to generate ^ PAW Atomic Datasets*  

E-Print Network [OSTI]

1/28/2014 CFCAM Workshop 2014 1 Good How to generate ^ PAW Atomic Datasets* N. A. W. Holzwarth 2014 2 Good How to generate ^ PAW Atomic Datasets Challenges Tricks Opportunities for collaboration Importance of having several independent codes (both for atomic dataset generation and for materials

Holzwarth, Natalie

26

Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser  

E-Print Network [OSTI]

Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser fields-high-order harmonic generation HHG from Ar atoms and Ar+ ions by means of the self-interaction-free time-order harmonic generation HHG is one of the most rapidly developing topics in the field of laser-atom molecule

Chu, Shih-I

27

Metal Hydride Hydrogen Storage R and D | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Metal Hydride Hydrogen Storage R and D Metal Hydride Hydrogen Storage R and D DOE's research on complex metal hydrides targets the development of advanced metal hydride materials...

28

Outcomes of Chronic Arsenic Exposure on Aquatic Insects  

E-Print Network [OSTI]

electrothermal atomic absorption spectrometry. AnalyticaHydride Generated Atomic Absorption Spectroscopy (HGAAS) andHydride Generated Atomic Absorption Spectroscopy (HGAAS).

Mogren, Christina Loraine

2013-01-01T23:59:59.000Z

29

E-Print Network 3.0 - atomic nano-generators actinium-225-labeled...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

nano-generators actinium-225-labeled Search Powered by Explorit Topic List Advanced Search Sample search results for: atomic nano-generators actinium-225-labeled Page: << < 1 2 3 4...

30

Generation of genuine $?$-type four-particle entangled state of superconducting artificial atoms with broken symmetry  

E-Print Network [OSTI]

We propose a scheme for generating a genuine $\\chi$-type four-particle entangled state of superconducting artificial atoms with broken symmetry by using one-dimensional transmission line resonator as a data bus. The $\\Delta$-type three-level artificial atom we use in the scheme is different from natural atom and has cyclic transitions. After suitable interaction time and simple operations, the desired entangled state can be obtained. Since artificial atomic excited states and photonic states are adiabatically eliminated, our scheme is robust against the spontaneous emissions of artificial atoms and the decays of transmission line resonator.

Chun-Ling Leng; Qi Guo; Xin Ji; Shou Zhang

2014-12-11T23:59:59.000Z

31

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

32

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, Moshe (Haifa, IL); Gruen, Dieter M. (Downers Grove, IL); Mendelsohn, Marshall H. (Woodridge, IL); Sheft, Irving (Oak Park, IL)

1981-01-01T23:59:59.000Z

33

Hydrogen Outgassing from Lithium Hydride  

SciTech Connect (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

34

Generation of maximally entangled mixed states of two atoms via on-resonance asymmetric atom-cavity couplings  

E-Print Network [OSTI]

A scheme for generating the maximally entangled mixed state of two atoms on-resonance asymmetrically coupled to a single mode optical cavity field is presented. The part frontier of both maximally entangled mixed states and maximal Bell violating mixed states can be approximately reached by the evolving reduced density matrix of two atoms if the ratio of coupling strengths of two atoms is appropriately controlled. It is also shown that exchange symmetry of global maximal concurrence is broken if and only if coupling strength ratio lies between $\\frac{\\sqrt{3}}{3}$ and $\\sqrt{3}$ for the case of one-particle excitation and asymmetric coupling, while this partial symmetry-breaking can not be verified by detecting maximal Bell violation.

Shang-Bin Li

2006-10-22T23:59:59.000Z

35

Influence of uranium hydride oxidation on uranium metal behaviour  

SciTech Connect (OSTI)

This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

Patel, N.; Hambley, D. [National Nuclear Laboratory (United Kingdom); Clarke, S.A. [Sellafield Ltd (United Kingdom); Simpson, K.

2013-07-01T23:59:59.000Z

36

Generation of Werner states via collective decay of coherently driven atoms  

E-Print Network [OSTI]

We show deterministic generation of Werner states as a steady state of the collective decay dynamics of a pair of neutral atom coupled to a leaky cavity and strong coherent drive. We also show how the scheme can be extended to generate $2N$-particle analogue of the bipartite Werner states.

Girish S. Agarwal; Kishore T. Kapale

2005-10-13T23:59:59.000Z

37

Thermodynamic Studies and Hydride Transfer Reactions from a Rhodium Complex to BX3 Compounds  

SciTech Connect (OSTI)

This study examines the use of transition-metal hydride complexes that can be generated by the heterolytic cleavage of H2 gas to form B–H bonds. Specifically, these studies are focused on providing a reliable and quantitative method for determining when hydride transfer from transition-metal hydrides to three-coordinate BX3 compounds will be favorable. This involves both experimental and theoretical determinations of hydride transfer abilities. Thermodynamic hydride donor abilities (?G°H-) were determined for HRh(dmpe)2 and HRh(depe)2, where dmpe = 1,2-bis(dimethylphosphinoethane) and depe = 1,2-bis(diethylphosphinoethane), on a previously established scale in acetonitrile. This hydride donor ability was used to determine the hydride donor ability of [HBEt3]? on this scale. Isodesmic reactions between [HBEt3]? and various BX3 complexes to form BEt3 and [HBX3]? were examined computationally to determine the relative hydride affinities of various BX3 compounds. The use of these scales of hydride donor abilities and hydride affinities for transition-metal hydrides and BX3 compounds is illustrated with a few selected reactions relevant to the regeneration of ammonia borane. Our findings indicate that it is possible to form B?H bonds from B?X bonds, and the extent to which BX3 compounds are reduced by transition-metal hydride complexes forming species containing multiple B?H bonds depends on the heterolytic B?X bond energy. An example is the reduction of B(SPh)3 using HRh(dmpe)2 in the presence of triethylamine to form Et3N-BH3 in high yields. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

Mock, Michael T.; Potter, Robert G.; Camaioni, Donald M.; Li, Jun; Dougherty, William G.; Kassel, W. S.; Twamley, Brendan; DuBois, Daniel L.

2009-10-14T23:59:59.000Z

38

Erbium hydride decomposition kinetics.  

SciTech Connect (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

39

Complex Hydrides for Hydrogen Storage  

SciTech Connect (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

40

Carrier-wave Rabi flopping signatures in high-order harmonic generation for alkali atoms  

E-Print Network [OSTI]

We present the first theoretical investigation of carrier-wave Rabi flopping in real atoms by employing numerical simulations of high-order harmonic generation (HHG) in alkali species. Given the short HHG cutoff, related to the low saturation intensity, we concentrate on the features of the third harmonic of sodium (Na) and potassium (K) atoms. For pulse areas of 2$\\pi$ and Na atoms, a characteristic unique peak appears, which, after analyzing the ground state population, we correlate with the conventional Rabi flopping. On the other hand, for larger pulse areas, carrier-wave Rabi flopping occurs, and is associated with a more complex structure in the third harmonic. These new characteristics observed in K atoms indicate the breakdown of the area theorem, as was already demonstrated under similar circumstances in narrow band gap semiconductors.

Ciappina, M F; Landsman, A S; Zimmermann, T; Lewenstein, M; Roso, L; Krausz, F

2015-01-01T23:59:59.000Z

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.


41

Protecting and Dynamically Generating Entanglement in a Two-Atom Two-Field-Mode Model  

E-Print Network [OSTI]

We analyze the time evolution of quantum entanglement in a model consisting of two two-level atoms interacting with a two-mode electromagnetic field for a variety of initial states. We study two different coupling schemes motivated by the forms that can arise due to atomic separation. We observe a variety of qualitative features such as entanglement sudden death, dynamical generation, protection, and transfer between subsystems. Our quantitative analysis shows that these cases with different couplings and initial states differ significantly in these qualitative features. The multifarious behaviors in these two-mode cases suggest the importance of considering atomic separation carefully for any model where two atoms interact with a common field.

K. Sinha; N. Cummings; B. L. Hu

2010-10-06T23:59:59.000Z

42

Arc plasma generator of atomic driver for steady-state negative ion source  

SciTech Connect (OSTI)

The paper reviews the results of development of steady-state arc-discharge plasma generator with directly heated LaB{sub 6} cathode. This arc-discharge plasma generator produces a plasma jet which is to be converted into an atomic one after recombination on a metallic plate. The plate is electrically biased relative to the plasma in order to control the atom energies. Such an intensive jet of hydrogen atoms can be used in negative ion sources for effective production of negative ions on a cesiated surface of plasma grid. All elements of the plasma generator have an augmented water cooling to operate in long pulse mode or in steady state. The thermo-mechanical stresses and deformations of the most critical elements of the plasma generator were determined by simulations. Magnetic field inside the discharge chamber was optimized to reduce the local power loads. The first tests of the steady-state arc plasma generator prototype have performed in long-pulse mode.

Ivanov, A. A.; Belchenko, Yu. I.; Davydenko, V. I. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation) [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Ivanov, I. A.; Kolmogorov, V. V.; Listopad, A. A., E-mail: a.a.listopad@inp.nsk.su; Mishagin, V. V.; Shulzhenko, G. I. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)] [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Putvinsky, S. V.; Smirnov, A. [Tri Alpha Energy Inc., Rancho Santa Margarita, California 92688 (United States)] [Tri Alpha Energy Inc., Rancho Santa Margarita, California 92688 (United States)

2014-02-15T23:59:59.000Z

43

Synthesis and Hydride Transfer Reactions of Cobalt and Nickel Hydride Complexes to BX3 Compounds  

SciTech Connect (OSTI)

Hydrides of numerous transition metal complexes can be generated by the heterolytic cleavage of H{sub 2} gas such that they offer alternatives to using main group hydrides in the regeneration of ammonia borane, a compound that has been intensely studied for hydrogen storage applications. Previously, we reported that HRh(dmpe){sub 2}, dmpe = 1,2-bis(dimethylphosphinoethane) was capable of reducing a variety of BX{sub 3} compounds having hydride affinity (HA) greater than or equal to HA of BEt{sub 3}. This study examines the reactivity of less expensive cobalt and nickel hydride complexes, (HCo(dmpe){sub 2} and [HNi(dmpe){sub 2}]{sup +}), to form B-H bonds. The hydride donor abilities ({Delta}G{sub H{sup -}}{sup o}) of HCo(dmpe){sub 2} and [HNi(dmpe){sub 2}]{sup +} were positioned on a previously established scale in acetonitrile that is cross-referenced with calculated HAs of BX{sub 3} compounds. The collective data guided our selection of BX{sub 3} compounds to investigate and aided our analysis of factors that determine favorability of hydride transfer. HCo(dmpe){sub 2} was observed to transfer H{sup -} to BX{sub 3} compounds with X = H, OC{sub 6}F{sub 5} and SPh. The reaction with B(SPh){sub 3} is accompanied by formation of (BH{sub 3}){sub 2}-dmpe and (BH{sub 2}SPh){sub 2}-dmpe products that follow from reduction of multiple BSPh bonds and loss of a dmpe ligand from Co. Reactions between HCo(dmpe){sub 2} and B(SPh){sub 3} in the presence of triethylamine result in formation of Et{sub 3}N-BH{sub 2}SPh and Et{sub 3}N-BH{sub 3} with no loss of dmpe ligand. Reactions of the cationic complex [HNi(dmpe){sub 2}]{sup +} with B(SPh){sub 3} under analogous conditions give Et{sub 3}N-BH{sub 2}SPh as the final product along with the nickel-thiolate complex [Ni(dmpe){sub 2}(SPh)]{sup +}. The synthesis and characterization of HCo(dedpe){sub 2} (dedpe = diethyldiphenyl(phosphino)ethane) from H{sub 2} and a base is also discussed; including the formation of an uncommon trans dihydride species, trans-[(H{sub 2})Co(dedpe){sub 2}][BF{sub 4}].

Mock, Michael T.; Potter, Robert G.; O'Hagan, Molly J.; Camaioni, Donald M.; Dougherty, William G.; Kassel, W. S.; DuBois, Daniel L.

2011-12-05T23:59:59.000Z

44

Regeneration of Aluminum Hydride - Energy Innovation Portal  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

hydride is an attractive alternative to the traditional metal hydrides for the storage of hydrogen for its use as an energy source. Alanes use as the primary source of hydrogen has...

45

E-Print Network 3.0 - alkali metal hydrides Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Hf for selected alkali metal hydrides, alkaline earth metal hydrides, transition metal hydrides... of binary hydrides based on alkali metals, alkaline earth ... Source:...

46

Hydrogen, lithium, and lithium hydride production  

DOE Patents [OSTI]

A method of producing high purity lithium metal is provided, where gaseous-phase lithium metal is extracted from lithium hydride and condensed to form solid high purity lithium metal. The high purity lithium metal may be hydrided to provide high purity lithium hydride.

Brown, Sam W; Spencer, Larry S; Phillips, Michael R; Powell, G. Louis; Campbell, Peggy J

2014-03-25T23:59:59.000Z

47

Evidence of Catalytic Production of Hot Atomic Hydrogen in RF Generated Hydrogen/Helium Plasmas  

E-Print Network [OSTI]

A study of the line shapes of hydrogen Balmer series lines in RF generated low pressure H2/He plasmas produced results suggesting a catalytic process between helium and hydrogen species results in the generation of 'hot' (ca. 28 eV) atomic hydrogen. Even far from the electrodes 'hot' atomic hydrogen was predominant in H2/He plasmas. Line shapes, relative line areas of cold and hot atomic hydrogen (hot/cold>2.5), were very similar for areas between the electrodes and far from the electrodes for these plasmas. In contrast, in H2/Xe only 'warm' (hydrogen (warm/coldhydrogen away from the electrodes. Earlier postulates that preferential hydrogen line broadening in plasmas results from the acceleration of ionic hydrogen in the vicinity of electrodes, and the special charge exchange characteristics of Ar/H2+ are clearly belied by the present results that show atomic hydrogen line shape are similar for H2/He plasmas throughout the relatively large cylindrical (14 cm ID x 36 cm length) cavity.

Jonathan Phillips; Chun-Ku Chen; Toshi Shiina

2005-09-14T23:59:59.000Z

48

High-order harmonic generation in atomic hydrogen at 248 nm: Dipole-moment versus acceleration spectrum  

E-Print Network [OSTI]

We present a study of the high-order harmonic-generation (HG) spectra of atomic hydrogen at 248 nm based on the Fourier transform of the expectation values of the induced dipole moment and acceleration. The calculations ...

Jiang, Tsin-Fu; Chu, Shih-I

1992-12-01T23:59:59.000Z

49

First-principles calculations of niobium hydride formation in superconducting radio-frequency cavities  

SciTech Connect (OSTI)

Niobium hydride is suspected to be a major contributor to degradation of the quality factor of niobium superconducting radio-frequency (SRF) cavities. In this study, we connect the fundamental properties of hydrogen in niobium to SRF cavity performance and processing. We modeled several of the niobium hydride phases relevant to SRF cavities and present their thermodynamic, electronic, and geometric properties determined from calculations based on density-functional theory. We find that the absorption of hydrogen from the gas phase into niobium is exothermic and hydrogen becomes somewhat anionic. The absorption of hydrogen by niobium lattice vacancies is strongly preferred over absorption into interstitial sites. A single vacancy can accommodate six hydrogen atoms in the symmetrically equivalent lowest-energy sites and additional hydrogen in the nearby interstitial sites affected by the strain field: this indicates that a vacancy can serve as a nucleation center for hydride phase formation. Small hydride precipitates may then occur near lattice vacancies upon cooling. Vacancy clusters and extended defects should also be enriched in hydrogen, potentially resulting in extended hydride phase regions upon cooling. We also assess the phase changes in the niobium-hydrogen system based on charge transfer between niobium and hydrogen, the strain field associated with interstitial hydrogen, and the geometry of the hydride phases. The results of this study stress the importance of not only the hydrogen content in niobium, but also the recovery state of niobium for the performance of SRF cavities.

Ford, Denise C.; Cooley, Lance D.; Seidman, David N.

2013-09-01T23:59:59.000Z

50

Igniter containing titanium hydride and potassium perchlorate  

DOE Patents [OSTI]

An explosive device is described which employs a particular titanium hydride-potassium perchlorate composition directly ignitible by an electrical bridgewire.

Dietzel, Russel W. (Albuquerque, NM); Leslie, William B. (Albuquerque, NM)

1976-01-01T23:59:59.000Z

51

Comprehensive Thermodynamics of Nickel Hydride Bis(Diphosphine...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Thermodynamics of Nickel Hydride Bis(Diphosphine) Complexes: A Predictive Model through Computations. Comprehensive Thermodynamics of Nickel Hydride Bis(Diphosphine) Complexes: A...

52

Neutron Irradiation of Hydrided Cladding Material in HFIR Summary...  

Broader source: Energy.gov (indexed) [DOE]

Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of Initial Activities Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of Initial Activities...

53

argon hydrides: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

authors 2 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

54

aluminium hydrides: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Norman A. 3 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

55

Incorporation of Hydride Nuclear Fuels in Commercial Light Water Reactors  

E-Print Network [OSTI]

of hydride fueled BWRs. Nuclear Engineering and Design, 239:Fueled PWR Cores. Nuclear Engineering and Design, 239:1489–Hydride Fueled LWRs. Nuclear Engineering and Design, 239:

Terrani, Kurt Amir

2010-01-01T23:59:59.000Z

56

ITOUGH2 Software Qualification  

E-Print Network [OSTI]

hydride generation atomic absorption spectrometry with on-B y conventional flame atomic absorption (FLAA) methods,hydride generation atomic absorption spectrometry with on-

Fraser, P.

2010-01-01T23:59:59.000Z

57

Selenium Fractionation and Cycling in the Intertidal Zone of the Carquinez Strait - October 1995 to December 1995  

E-Print Network [OSTI]

hydride generation atomic absorption spectrometry with on-B y conventional flame atomic absorption (FLAA) methods,hydride generation atomic absorption spectrometry with on-

Zawislanski, P.T.

2010-01-01T23:59:59.000Z

58

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

59

Diffusional exchange of isotopes in a metal hydride sphere.  

SciTech Connect (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

60

X-ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin Films  

E-Print Network [OSTI]

X-ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin Films T. J. Richardsona@lbl.gov Abstract Mixed metal thin films containing magnesium and a first-row transition element exhibit very large and coordination of the magnesium and transition metal atoms during hydrogen absorption were studied using dynamic

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61

Hydriding and dehydriding characteristics of LiBH{sub 4} and transition metals-added magnesium hydride  

SciTech Connect (OSTI)

Graphical abstract: Hydriding reaction curves under 12 bar H{sub 2}, and dehydriding reaction curves under 1.0 bar H{sub 2}, at 593 K at the 1st cycle for MgH{sub 2}–10Ni–2LiBH{sub 4}–2Ti and MgH{sub 2}. Highlights: ? Addition of Ni, LiBH{sub 4}, and Ti to MgH{sub 2} to increase reaction rates. ? Sample preparation by reactive mechanical grinding. ? At n = 2, the sample absorbed 4.05 wt% H for 60 min at 593 K under 12 bar H{sub 2}. ? Analysis of rate-controlling step for dehydriding of the sample at n = 3. - Abstract: In this study, MgH{sub 2} was used as a starting material instead of Mg. Ni, Ti, and LiBH{sub 4} with a high hydrogen-storage capacity of 18.4 wt% were added. A sample with a composition of MgH{sub 2}–10Ni–2LiBH{sub 4}–2Ti was prepared by reactive mechanical grinding. The activation of MgH{sub 2}–10Ni–2LiBH{sub 4}–2Ti was completed after the first hydriding–dehydrding cycle. The hydriding rate decreases as the temperature increases due to the decrease in the driving force for the hydriding reaction. At the 1st cycle, the sample desorbs 1.45 wt% H for 10 min, 2.54 wt% H for 20 min, 3.13 wt% H for 30 min, and 3.40 wt% H for 60 min at 593 K under 1.0 bar H{sub 2}. At the 2nd cycle, the sample absorbs 3.84 wt% H for 5 min, 3.96 wt% H for 10 min, and 4.05 wt% H for 60 min at 593 K under 12 bar H{sub 2}. MgH{sub 2}–10Ni–2LiBH{sub 4}–2Ti after reactive mechanical grinding contained MgH{sub 2}, Mg, Ni, TiH{sub 1.924}, and MgO phases. The reactive mechanical grinding of Mg with Ni, LiBH{sub 4}, and Ti is considered to create defects on the surface and in the interior of Mg (to facilitate nucleation), and to reduce the particle size of Mg (to shorten diffusion distances of hydrogen atoms). The formation of Mg{sub 2}Ni during hydriding–dehydriding cycling increases the hydriding and dehydriding rates of the sample.

Song, Myoung Youp, E-mail: songmy@jbnu.ac.kr [Division of Advanced Materials Engineering, Hydrogen and Fuel Cell Research Center, Engineering Research Institute, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, 561-756 (Korea, Republic of); Kwak, Young Jun; Lee, Seong Ho [Department of Materials Engineering, Graduate School, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, 561-756 (Korea, Republic of); Park, Hye Ryoung [Faculty of Applied Chemical Engineering, Chonnam National University, 300 Yongbongdong, Bukgu, Gwangju, 500-757 (Korea, Republic of)

2013-07-15T23:59:59.000Z

62

Experimental generation of tripartite telecom photons via an atomic ensemble and a nonlinear waveguide  

E-Print Network [OSTI]

Non-classical multi-photon and number states attracts many people because of their wide applications in fundamental quantum mechanics tests, quantum metrology and quantum computation, therefore it is a longstanding aim to generate such states experimentally. Here, we prepare photon triplets by using the spontaneously Raman scattering process in a hot atomic ensemble cascaded by the spontaneous parametric down conversion process in a periodical poled nonlinear waveguide, the strong temporal correlations of these three photons are observed. Our experiment represents the first combination of the different order nonlinear processes and different physical systems, showing the feasibility of such composite system in this research direction. In addition, the all photons in the prepared genuine triplet are in telecom band make them be suitable for long-distance quantum communication in optical fibre.

Dong-Sheng Ding; Wei Zhang; Shuai Shi; Zhi-Yuan Zhou; Yan Li; Bao-Sen Shi; Guang-Can Guo

2015-01-12T23:59:59.000Z

63

Direct synthesis of catalyzed hydride compounds  

DOE Patents [OSTI]

A method is disclosed for directly preparing alkali metal aluminum hydrides such as NaAlH.sub.4 and Na.sub.3 AlH.sub.6 from either the alkali metal or its hydride, and aluminum. The hydride thus prepared is doped with a small portion of a transition metal catalyst compound, such as TiCl.sub.3, TiF.sub.3, or a mixture of these materials, in order to render them reversibly hydridable. The process provides for mechanically mixing the dry reagents under an inert atmosphere followed by charging the mixed materials with high pressure hydrogen while heating the mixture to about 125.degree. C. The method is relatively simple and inexpensive and provides reversible hydride compounds which are free of the usual contamination introduced by prior art wet chemical methods.

Gross, Karl J.; Majzoub, Eric

2004-09-21T23:59:59.000Z

64

Effects of outgassing of loader chamber walls on hydriding of thin films for commercial applications  

SciTech Connect (OSTI)

An important aspect of understanding industrial processing is to know the characteristics of the materials used in such processes. A study was performed to determine the effects of hydriding chamber material on the degree of hydriding for the commercial production of thin film hydride targets for various research universities, commercial companies, and government national laboratories. The goal was to increase the degree of hydriding of various thin film hydrides and to study the vacuum environment during air-exposure hydriding. For this purpose, dynamic residual gas analysis during deuterium gas hydride processing was utilized with erbium thin films, employing a special set-up for direct dynamic hydride gas sampling during processing at elevated temperature and full loading gas pressure. Complete process data for (1) a copper–(1.83?wt.?%)beryllium wet hydrogen fired passivated (600?°C–1?h) externally heated pipe hydriding chamber are reported. Dynamic residual gas analysis comparisons during hydriding are presented for hydriding chambers made from (2) alumina (99.8 wt.?%), (3) copper (with an interior aluminum coating ?10 k Å thick, and (4) for a stainless-steel air-fired passivated (900?°C–1?h) chamber. Dynamic data with deuterium gas in the chamber at the hydriding temperature (450?°C) showed the presence and growth of water vapor (D{sub 2}O) and related mixed ion species(H{sub 2}O{sup +}, HDO{sup +}, D{sub 2}O{sup +}, and OD{sup +}) from hydrogen isotope exchange reactions during the 1?h process time. Peaks at mass-to-charge ratios (i.e., m/e) of 12(C{sup +}), 16(CD{sub 2}{sup +}), 17(CHD{sub 2}{sup +}), and 18(CD{sub 3}{sup +}, OD{sup +}) increased for approximately the first half hour of a 1?h hydriding process and then approach steady state. Mass-to-charge peaks at 19(HDO{sup +}) and 20(D{sub 2}O{sup +}) continue to increase throughout the process cycle. Using the m/e?=?20 (D{sub 2}O{sup +}) peak intensity from chamber (1)–Cu(1.83 wt.?%)Be as a standard, the peak intensity from chamber (4)—stainless-steel (air-fired) was 7.1× higher, indicating that the surface of stainless-steel had a larger concentration of reactive oxygen and/or water than hydrogen. The (D{sub 2}O{sup +}) peak intensity from chamber (3)—Cu (interior Al coating) was 1.55× larger and chamber (2)—alumina(99.8%) was 1.33× higher than Cu(1.83 wt.?%)Be. Thus copper–(1.83 wt.?%)beryllium was the best hydriding chamber material studied followed closely by the alumina (99.8 wt.?%) chamber. Gas take-up by Er occluder targets processed in Cu(1.83?wt.?%)Be hydriding chambers (i.e., gas/metal atomic ratios) correlate with the dynamic RGA data.

Provo, James L., E-mail: jlprovo@verizon.net [Consultant, J.L. Provo Consulting, Trinity, Florida 34655-7179 (United States)

2014-07-01T23:59:59.000Z

65

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

66

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

E-Print Network [OSTI]

) to avoid oxygen gas generation during over discharge and has extra capacity to avoid hydrogen gas generation during over- charge. Since the metal hydride material gradually loses capacity through usage due. The side reaction at the positive electrode is oxygen evolu- tion and at the negative electrode oxygen

67

Squeezed-state generation via nonlinear atom-atom interaction in the atomic field of a Bose-Einstein condensate interacting with an optical cavity  

E-Print Network [OSTI]

In this paper, we investigate theoretically a system consisting of a one dimensional Bose-Einstein condensate trapped inside the optical lattice of an optical cavity. In the weak-interaction regime and under the Bogoliubov approximation, the wave function of the Bose-Einstein condensate can be described by a classical field (condensate mode) having some quantum fluctuations (the Bogoliubov mode) about the mean value. Such a system behaves as a so-called atomic parametric amplifier, similar to an optical parametric amplifier, where the condensate and the Bogoliubov modes play respectively, the roles of the pump field and the signal mode in the degenerate parametric amplifier and the s-wave scattering frequency of atom-atom interaction plays the role of the nonlinear gain parameter. We show that using the nonlinear effect of atomic collisions, how one can manipulate and control the state of the Bogoliubov mode and produce squeezed states.

A. Dalafi; M. H. Naderi; M. Soltanolkotabi

2014-03-29T23:59:59.000Z

68

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

2012-04-10T23:59:59.000Z

69

Electrochemical process and production of novel complex hydrides  

DOE Patents [OSTI]

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

70

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

71

Characteristics of cooperative spontaneous radiation with applications to atom microscopy and coherent XUV radiation generation  

E-Print Network [OSTI]

quicker than single atom decay, with a decay rate proportional to N(?/R)2, where N is the atom numbers, R is the size of the atom cloud, and ? is the wavelength. We call it Markovian regime because the sytem does not persist memory effect. The other regime...

Chang, Juntao

2009-05-15T23:59:59.000Z

72

High-order harmonic generation in atomic hydrogen at 248 nm: Dipole-moment versus acceleration spectrum  

E-Print Network [OSTI]

We present a study of the high-order harmonic-generation (HG) spectra of atomic hydrogen at 248 nm based on the Fourier transform of the expectation values of the induced dipole moment and acceleration. The calculations were performed by extending a...

Jiang, Tsin-Fu; Chu, Shih-I

1992-12-01T23:59:59.000Z

73

Observations of proton beam enhancement due to erbium hydride on gold foil targets  

SciTech Connect (OSTI)

Recent theoretical work suggests that the conversion efficiency from laser to protons in laser irradiated thin foil experiments increases if the atomic mass of nonhydrogen atoms on the foil rear surface increases. Experiments were performed at the Lawrence Livermore National Laboratory Jupiter Laser Facility to observe the effect of thin foils coated with erbium hydride on the conversion efficiency from laser to protons. Gold foils with and without the rear surface coated with ErH{sub 3} were irradiated using the ultrashort pulse, 40 TW Callisto laser. An argon-ion etching system was used to remove naturally occurring nanometer thick surface layer contaminants from the hydride. With the etcher, gold with ErH{sub 3} showed a 25% increase in the conversion efficiency to protons above 3.4 MeV relative to contaminants, where C{sup +4} and H{sup +} were the dominant ion species. No difference in the ion signal was observed without first cleaning the hydrides. Simulations using the hybrid PIC code, LSP, revealed that the increase due to erbium hydride versus contaminants is 37% for protons above 3 MeV.

Offermann, D. T.; Van Woerkom, L. D. [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States); Freeman, R. R. [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States); Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California 92093 (United States); Department of Applied Science, University of California Davis, Livermore, California 94550 (United States); Foord, M. E.; Hey, D.; Key, M. H.; Mackinnon, A. J.; MacPhee, A. G.; Patel, P. K.; Ping, Y.; Sanchez, J. J.; Shen, N. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Bartal, T.; Beg, F. N. [Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California 92093 (United States); Espada, L. [Sandia National Laboratory, Albuquerque, New Mexico 87185 (United States); Chen, C. D. [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2009-09-15T23:59:59.000Z

74

Generation of two-color EPR-entangled optical beams in macroscopic atomic ensembles  

SciTech Connect (OSTI)

We present a protocol for deterministically producing continuous-variable Einstein-Podolsky-Rosen- (EPR-) entangled optical beams in macroscopic atomic ensembles. In contrast to previous cavity-based schemes, our protocol requires only a single pass of two coherent light beams through two spin-polarized free-space atomic vapors, which greatly simplifies the experimental implementation and makes the scheme very efficient. The two entangled modes have a frequency difference of about twice the Zeeman frequency of the atomic vapors, which can be widely tuned via magnetic-field control. Under realistic experimental conditions, we show that large entanglement could be created even with room-temperature atomic vapors.

Wang Mingfeng; Gu Wenjing; Jin Qingli; Zheng Yizhuang [School of Physics and Electronics Information Engineering, Wenzhou University, Wenzhou 325027 (China)

2010-10-15T23:59:59.000Z

75

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

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

americium hydrides: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2012-01-01 3 Geoneutrino and Hydridic Earth model CERN Preprints Summary: Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic...

78

A PROTOTYPE FOUR INCH SHORT HYDRIDE (FISH) BED AS A REPLACEMENT TRITIUM STORAGE BED  

SciTech Connect (OSTI)

The Savannah River Site (SRS) tritium facilities have used 1st generation (Gen1) metal hydride storage bed assemblies with process vessels (PVs) fabricated from 3 inch nominal pipe size (NPS) pipe to hold up to 12.6 kg of LaNi{sub 4.25}Al{sub 0.75} metal hydride for tritium gas absorption, storage, and desorption for over 15 years. The 2nd generation (Gen2) of the bed design used the same NPS for the PV, but the added internal components produced a bed nominally 1.2 m long, and presented a significant challenge for heater cartridge replacement in a footprint limited glove-box. A prototype 3rd generation (Gen3) metal hydride storage bed has been designed and fabricated as a replacement candidate for the Gen2 storage bed. The prototype Gen3 bed uses a PV pipe diameter of 4 inch NPS so the bed length can be reduced below 0.7 m to facilitate heater cartridge replacement. For the Gen3 prototype bed, modeling results show increased absorption rates when using hydrides with lower absorption pressures. To improve absorption performance compared to the Gen2 beds, a LaNi{sub 4.15}Al{sub 0.85} material was procured and processed to obtain the desired pressure-composition-temperature (PCT) properties. Other bed design improvements are also presented.

Klein, J.; Estochen, E.; Shanahan, K.; Heung, L.

2011-02-23T23:59:59.000Z

79

Geoneutrino and Hydridic Earth model. Version 2  

E-Print Network [OSTI]

Uranium, Thorium and Potassium-40 abundances in the Earth were calculated in the frame of Hydridic Earth model. Terrestrial heat producton from U, Th and K40 decays was calculated also. We must admit the existance of Earth expansion process to understand the obtained large value of terrestrial heat producton. The geoneutrino detector with volume more than 5 kT (LENA type) must be constructed to definitely separate between Bulk Silicat Earth model and Hydridic Earth model. In second version of the article we assume that K40 concentration distributes in the Earth uniformly.

Leonid Bezrukov

2014-02-12T23:59:59.000Z

80

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

DOE Patents [OSTI]

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

E-Print Network 3.0 - atomic hydrogen generated Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

to greenhouse gas emissions: 1... generation or the transportation sector 18-20. 3. Hydrogen costs by electrolysis A case study... is needed, due to longer periods without...

82

Encapsulated Metal Hydride for Hydrogen Separation  

E-Print Network [OSTI]

concentration feed stock, not for low concentration ­ Hydrogen economy will need hydrogen recovery from lowEncapsulated Metal Hydride for Hydrogen Separation (Formerly Separation Membrane Development) DOE Hydrogen Program 2003 Merit Review and Peer Evaluation L. Kit Heung, Jim Congdon Savannah River Technology

83

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

84

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

2009-05-05T23:59:59.000Z

85

Ductility Evaluation of As-Hydrided and Hydride Reoriented Zircaloy-4 Cladding under Simulated Dry-Storage Condition  

SciTech Connect (OSTI)

Pre-storage drying-transfer operations and early stage storage expose cladding to higher temperatures and much higher pressure-induced tensile hoop stresses relative to normal operation in-reactor and pool storage under these conditions. Radial hydrides could precipitate during slow cooling and provide an additional embrittlement mechanism as the cladding temperature decreases below the ductile-to-brittle transition temperature. As a means of simulating this behavior, unirradiated hydrided Zircaloy-4 samples were fabricated by a gas charging method to levels that encompass the range of hydrogen concentrations observed in current used fuel. Mechanical testing was carried out by the ring compression test (RCT) method at various temperatures to evaluate the sample s ductility for both as-hydrided and post-hydride reorientation treated specimens. As-hydrided samples with higher hydrogen concentration (>800 ppm) resulted in lower strain before fracture and reduced maximum load. Increasing RCT temperatures resulted in increased ductility of the as-hydrided cladding. A systematic radial hydride treatment was conducted at various pressures and temperatures for the hydrided samples with H content around 200 ppm. Following the radial hydride treatment, RCTs on the hydride reoriented samples were conducted and exhibited lower ductility compared to as-hydrided samples.

Yan, Yong [ORNL] [ORNL; Plummer, Lee K [ORNL] [ORNL; Ray, Holly B [ORNL] [ORNL; Cook, Tyler S [ORNL] [ORNL; Bilheux, Hassina Z [ORNL] [ORNL

2014-01-01T23:59:59.000Z

86

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

SciTech Connect (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

87

Comparative investigation of third- and fifth-harmonic generation in atomic and molecular gases driven by midinfrared ultrafast laser pulses  

SciTech Connect (OSTI)

We report on the comparative experimental investigation on third- and fifth-harmonic generation (THG and FHG) in atomic and molecular gases driven by midinfrared ultrafast laser pulses at a wavelength of {approx}1500 nm. We observe that the conversion efficiencies of both the THG and FHG processes saturate at similar peak intensities close to {approx}1.5 x 10{sup 14} W/cm{sup 2} for argon, nitrogen, and air, whose ionization potentials are close to each other. Near the saturation intensity, the ratio of yields of the FHG and THG reaches {approx}10{sup -1} for all the gases. Our results show that high-order Kerr effect seems to exist; however, contribution from the fourth-order Kerr refractive index coefficient alone is insufficient to balance the Kerr self-focusing without the assistance of plasma generation.

Ni Jielei; Yao Jinping; Zeng Bin; Chu Wei; Li Guihua; Zhang Haisu; Jing Chenrui [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 800-211, Shanghai 201800 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China); Chin, S. L. [Department of Physics, Engineering Physics and Optics, and Center for Optics, Photonics and Laser (COPL), Laval University, Laval, Quebec, G1K 7P4 (Canada); Cheng, Y.; Xu, Z. [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 800-211, Shanghai 201800 (China)

2011-12-15T23:59:59.000Z

88

On the thermodynamic efficiency of a multiferroic thermomagnetic generator: From bulk to atomic scale  

E-Print Network [OSTI]

Tes89] Nikola Tesla. “Thermo Magnetic Motor: US 396121 A. ”,realizing Tesla’s vision of a Curie motor [ACF13] [ACF14] [Tesla postulated the first type of thermomagnetic generator with his 1889 patent [Tes89] of a “Thermo Magnetic Motor,”

Sandoval, Samuel M.

2014-01-01T23:59:59.000Z

89

Proposed Virtual Center for Excellence for Metal Hydride Development...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Virtual Center for Excellence for Metal Hydride Development Presentation from the Hydrogen Storage Pre-Solicitation Meeting held June 19, 2003 in Washington, DC....

90

Mathematical modelling of a metal hydride hydrogen storage system.  

E-Print Network [OSTI]

??In order for metal hydride hydrogen storage systems to compete with existing energy storage technology, such as gasoline tanks and batteries, it is important to… (more)

MacDonald, Brendan David

2009-01-01T23:59:59.000Z

91

Final Report for the DOE Metal Hydride Center of Excellence  

Broader source: Energy.gov (indexed) [DOE]

Figure 9. Organometallic approach to incorporation of metal hydrides into C aerogels. ...42 Figure 10. Comparison of H 2 evolution from bulk-like ball milled...

92

Project Profile: Engineering a Novel High Temperature Metal Hydride...  

Office of Environmental Management (EM)

ELEMENTS) funding program, is developing a concept for high energy density thermochemical energy storage for concentrating solar power (CSP) using metal hydrides. These materials...

93

METAL HYDRIDE HYDROGEN COMPRESSORS: A REVIEW  

SciTech Connect (OSTI)

Metal hydride (MH) thermal sorption compression is an efficient and reliable method allowing a conversion of energy from heat into a compressed hydrogen gas. The most important component of such a thermal engine the metal hydride material itself should possess several material features in order to achieve an efficient performance in the hydrogen compression. Apart from the hydrogen storage characteristics important for every solid H storage material (e.g. gravimetric and volumetric efficiency of H storage, hydrogen sorption kinetics and effective thermal conductivity), the thermodynamics of the metal-hydrogen systems is of primary importance resulting in a temperature dependence of the absorption/desorption pressures). Several specific features should be optimized to govern the performance of the MH-compressors including synchronisation of the pressure plateaus for multi-stage compressors, reduction of slope of the isotherms and hysteresis, increase of cycling stability and life time, together with challenges in system design associated with volume expansion of the metal matrix during the hydrogenation. The present review summarises numerous papers and patent literature dealing with MH hydrogen compression technology. The review considers (a) fundamental aspects of materials development with a focus on structure and phase equilibria in the metal-hydrogen systems suitable for the hydrogen compression; and (b) applied aspects, including their consideration from the applied thermodynamic viewpoint, system design features and performances of the metal hydride compressors and major applications.

Bowman Jr, Robert C [ORNL] [ORNL; Yartys, Dr. Volodymyr A. [Institute for Energy Technology (IFE)] [Institute for Energy Technology (IFE); Lototskyy, Dr. Michael V [University of the Western Cape, South Africa] [University of the Western Cape, South Africa; Pollet, Dr. B.G. [University of the Western Cape, South Africa

2014-01-01T23:59:59.000Z

94

LANL/PNNL Virtual Center for Chemical Hydrides and New Concepts...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

LANLPNNL Virtual Center for Chemical Hydrides and New Concepts for Hydrogen Storage LANLPNNL Virtual Center for Chemical Hydrides and New Concepts for Hydrogen Storage...

95

Enhancement of field generation via maximal atomic coherence prepared by fast adiabatic passage in Rb vapor  

E-Print Network [OSTI]

shift s200 MHzd. The optical path lengths for both beams are the same. The temporal be- havior of the pulses is detected by fast photodiode D3. One beam serves as the first coupling pulse and the probe pulse. The time duration of the first coupling... with opposite circular polar- izations are separated by a second l /4 wave plate and an- other polarizing beamsplitter. The transmitted first coupling pulse and probe pulse are detected by fast photodiode D1. The second coupling pulse and the generated...

Sautenkov, V. A.; Ye, C. Y.; Rostovtsev, Y. V.; Welch, George R.; Scully, Marlan O.

2004-01-01T23:59:59.000Z

96

Generation of Free Oxygen Atoms O(3P) in Solution by Photolysis of 4-Benzoylpyridine N-Oxide  

SciTech Connect (OSTI)

Laser flash photolysis of 4-benzoylpyridine N-oxide (BPyO) at 308 nm in aqueous solutions generates a triplet excited state 3BPyO* that absorbs strongly in the visible, ?max 490 and 380 nm. 3BPyO* decays with the rate law kdecay/s?1 = (3.3 ± 0.9) × 104 + (1.5 ± 0.2) × 109 [BPyO] to generate a mixture of isomeric hydroxylated benzoylpyridines, BPy(OH), in addition to small amounts of oxygen atoms, O(3P). Molecular oxygen quenches 3BPyO*, kQ = 1.4 × 109 M?1 s?1, but the yields of O(3P) increase in O2-saturated solutions to 36%. Other triplet quenchers have a similar effect, which rules out the observed 3BPyO* as a source of O(3P). It is concluded that O(3P) is produced from either 1BPyO* or a short-lived, unobserved, higher energy triplet generated directly from 1BPyO*. 3BPyO* is reduced by Fe2+ and by ABTS2? to the radical anion BPyO?? which exhibits a maximum at 510 nm, ? = 2200 M?1 cm?1. The anion engages in back electron transfer with ABTS?? with k = 1.7 × 109 M?1 s?1. The same species can be generated by reducing ground state BPyO with ?C(CH3)2OH. The photochemistry of BPyO in acetonitrile is similar to that in aqueous solutions.

Carraher, Jack M. [Ames Laboratory; Bakac, Andreja [Ames Laboratory

2014-08-04T23:59:59.000Z

97

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

98

Separation Membrane Development (Separation Using Encapsulated Metal Hydride)  

E-Print Network [OSTI]

Separation Membrane Development (Separation Using Encapsulated Metal Hydride) L. Kit Heung Savannah: The first is to produce a sol-gel encapsulated metal hydride packing material that will a) absorbs hydrogen may be that hydrogen must come from multiple sources. These sources will include renewable (solar

99

A novel plating process for microencapsulating metal hydrides  

SciTech Connect (OSTI)

One approach to increasing the lifetime of the metal hydride electrode has been the use of conventional electroless plating to produce a coating of copper or nickel on the surface of the metal hydride powders. In this paper, a novel method for microencapsulating the active electrode powders is presented. This new plating technique takes advantage of the reducing power of hydrogen already stored inside the metal hydride to plate a variety of metals onto metal hydride materials. This method greatly simplifies electroless plating for these powders, eliminating the need for stabilizers and additives typically required for conventional electroless plating solutions. Metals that can be electrolessly plated with stored hydrogen have been identified based on thermodynamic considerations. Experimentally, micrometers thick coatings of copper, silver, and nickel have been plated on several metal hydrides.

Law, H.H.; Vyas, B.; Zahurak, S.M.; Kammlott, G.W. [AT and T Bell Labs., Murray Hill, NJ (United States)

1996-08-01T23:59:59.000Z

100

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

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

Recent advances in metal hydrides for clean energy applications  

SciTech Connect (OSTI)

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

102

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

103

Modular hydride beds for mobile applications  

SciTech Connect (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

104

Results of NDE Technique Evaluation of Clad Hydrides  

SciTech Connect (OSTI)

This report fulfills the M4 milestone, M4FT-14IN0805023, Results of NDE Technique Evaluation of Clad Hydrides, under Work Package Number FT-14IN080502. During service, zirconium alloy fuel cladding will degrade via corrosion/oxidation. Hydrogen, a byproduct of the oxidation process, will be absorbed into the cladding and eventually form hydrides due to low hydrogen solubility limits. The hydride phase is detrimental to the mechanical properties of the cladding and therefore it is important to be able to detect and characterize the presence of this constituent within the cladding. Presently, hydrides are evaluated using destructive examination. If nondestructive evaluation techniques can be used to detect and characterize the hydrides, the potential exists to significantly increase test sample coverage while reducing evaluation time and cost. To demonstrate the viability this approach, an initial evaluation of eddy current and ultrasonic techniques were performed to demonstrate the basic ability to these techniques to detect hydrides or their effects on the microstructure. Conventional continuous wave eddy current techniques were applied to zirconium based cladding test samples thermally processed with hydrogen gas to promote the absorption of hydrogen and subsequent formation of hydrides. The results of the evaluation demonstrate that eddy current inspection approaches have the potential to detect both the physical damage induced by hydrides, e.g. blisters and cracking, as well as the combined effects of absorbed hydrogen and hydride precipitates on the electrical properties of the zirconium alloy. Similarly, measurements of ultrasonic wave velocities indicate changes in the elastic properties resulting from the combined effects of absorbed hydrogen and hydride precipitates as well as changes in geometry in regions of severe degradation. However, for both approaches, the signal responses intended to make the desired measurement incorporate a number of contributing parameters. These contributing factors need to be recognized and a means to control them or separate their contributions will be required to obtain the desired information.

Dennis C. Kunerth

2014-09-01T23:59:59.000Z

105

Metal hydride fuel storage and method thereof  

DOE Patents [OSTI]

An apparatus having a first substrate having (1) a cavity, (2) one or more resistive heaters, and (3) one or more coatings forming a diffusion barrier to hydrogen; a second substrate having (1) an outlet valve comprising a pressure relief structure and (2) one or more coatings forming a diffusion barrier to hydrogen, wherein said second substrate is coupled to said first substrate forming a sealed volume in said cavity; a metal hydride material contained within said cavity; and a gas distribution system formed by coupling a microfluidic interconnect to said pressure relief structure. Additional apparatuses and methods are also disclosed.

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

2010-08-10T23:59:59.000Z

106

Highly Concentrated Palladium Hydrides/Deuterides; Theory  

SciTech Connect (OSTI)

Accomplishments are reported in these areas: tight-binding molecular dynamics study of palladium; First-principles calculations and tight-binding molecular dynamics simulations of the palladium-hydrogen system; tight-binding studies of bulk properties and hydrogen vacancies in KBH{sub 4}; tight-binding study of boron structures; development of angular dependent potentials for Pd-H; and density functional and tight-binding calculations for the light-hydrides NaAlH4 and NaBH4

Papaconstantopoulos, Dimitrios

2013-11-26T23:59:59.000Z

107

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

SciTech Connect (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

108

Chemical Hydride Slurry for Hydrogen Production and Storage  

SciTech Connect (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

109

ENVIRONMENTAL REACTIVITY OF SOLID STATE HYDRIDE MATERIALS  

SciTech Connect (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

110

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

SciTech Connect (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 BWR’s, and plutonium incineration capability. It was found that hydride fuel can safely operate in PWR’s and BWR’s 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 PWR’s and BWR’s 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 PWR’s 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 PWR’s. 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 PWR’s 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

111

Process for production of a metal hydride  

DOE Patents [OSTI]

A process for production of a metal hydride compound MH.sub.x, wherein x is one or two and M is an alkali metal, Be or Mg. The process comprises combining a compound of formula (R.sup.1O).sub.xM with aluminum, hydrogen and at least one metal selected from among titanium, zirconium, hafnium, niobium, vanadium, tantalum and iron to produce a compound of formula MH.sub.x. R.sup.1 is phenyl or phenyl substituted by at least one alkyl or alkoxy group. A mole ratio of aluminum to (R.sup.1O).sub.xM is from 0.1:1 to 1:1. The catalyst is present at a level of at least 200 ppm based on weight of aluminum.

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

2014-08-12T23:59:59.000Z

112

High capacity stabilized complex hydrides for hydrogen storage  

DOE Patents [OSTI]

Complex hydrides based on Al(BH.sub.4).sub.3 are stabilized by the presence of one or more additional metal elements or organic adducts to provide high capacity hydrogen storage material.

Zidan, Ragaiy; Mohtadi, Rana F; Fewox, Christopher; Sivasubramanian, Premkumar

2014-11-11T23:59:59.000Z

113

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

114

Metal Hydride Chemical Heat Pumps for Industrial Use  

E-Print Network [OSTI]

Hydriding alloys are intermetallic absorbent compounds which have the remarkable quality of absorbing very large quantities of hydrogen gas per unit volume of metallic powder. The absorption and desorption of hydrogen are exothermic and endothermic...

Ally, M. R.; Rebello, W. J.; Rosso, M. J., Jr.

1984-01-01T23:59:59.000Z

115

Development of a metal hydride electrode waste treatment process  

SciTech Connect (OSTI)

Manufacturing residues of metal hydride electrodes for nickel - metal hydride batteries were chemically processed to recover the metal part and heat treated for the organic part. Chemical recovery yielded Ni-Co alloy after electrolysis of the solution and hydroxides of other metal, mainly rare earths. The organic part, pyrolyzed at 700 C, led to separation between carbon and fluorinated matter. Infrared coupling at the output of the pyrolysis furnace was used to identify the pyrolysis gases.

Bianco, J.C.; Martin, D.; Ansart, F.; Castillo, S.

1999-12-01T23:59:59.000Z

116

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

SciTech Connect (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

117

Optimization of Hydride Rim Formation in Unirradiated Zr 4 Cladding  

SciTech Connect (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 400°C 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

OBSERVATIONS IN REACTIVITY BETWEEN BH CONTAINING COMPOUNDS AND ORGANOMETALLIC REAGENTS: SYNTHESIS OF BORONIC ACIDS, BORONIC ESTERS, AND MAGNESIUM HYDRIDES  

E-Print Network [OSTI]

Reaction of BH 3 :THF with magnesium hydride byproduct. A.It was also observed that magnesium hydride can partiallyACIDS, BORONIC ESTERS, AND MAGNESIUM HYDRIDES A dissertation

Clary, Jacob William

2012-01-01T23:59:59.000Z

119

Characterization and High Throughput Analysis of Metal Hydrides for Hydrogen Storage  

E-Print Network [OSTI]

Metal Hydrides for Hydrogen Storage by Steven James BarceloMetal Hydrides for Hydrogen Storage by Steven James BarceloCo-chair Efficient hydrogen storage is required for fuel

Barcelo, Steven James

2009-01-01T23:59:59.000Z

120

PREPRINT submitted to Journal of Physics B Electronic structure of the Magnesium hydride  

E-Print Network [OSTI]

PREPRINT submitted to Journal of Physics B Electronic structure of the Magnesium hydride molecular: 31.15.AR,31.15.Ct,31.50.Be,31.50.Df #12; Electronic structure of the Magnesium hydride molecular ion

Recanati, Catherine

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
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121

Storage, generation, and use of hydrogen  

DOE Patents [OSTI]

A composition comprising a carrier liquid; a dispersant; and a chemical hydride. The composition can be used in a hydrogen generator to generate hydrogen for use, e.g., as a fuel. A regenerator recovers elemental metal from byproducts of the hydrogen generation process.

McClaine, Andrew W.; Rolfe, Jonathan L.; Larsen, Christopher A.; Konduri, Ravi K.

2006-05-30T23:59:59.000Z

122

JOURNAL DE PHYSIQUE ColZoque C9, suppZe'ment au nO1l, Tome 41, novembre 1980, page C9-449 A POTENTIAL ATOMIC IODINE LASER PUMPED BY ELECTRICALLY GENERATED 'A OXYGEN  

E-Print Network [OSTI]

-449 A POTENTIAL ATOMIC IODINE LASER PUMPED BY ELECTRICALLY GENERATED 'A OXYGEN G. Fournier, J. Bonnet and D ation. This paper shows that an electron generator of 1~ oxygen [21 . A condition beam controlled discharge could be an for lasing is a concentration ratio ['A] / efficient oxygen generator to lase with C3z

Paris-Sud XI, Université de

123

Opening of a Post Doctoral Position Complex hydrides for hydrogen storage applications  

E-Print Network [OSTI]

Opening of a Post Doctoral Position Complex hydrides for hydrogen storage applications on complex hydrides for hydrogen storage applications in connection with the « Fast, reliable and cost effective boron hydride based high capacity solid state hydrogen storage materials» project co

124

THERMAL ENHANCEMENT CARTRIDGE HEATER MODIFIED TECH MOD TRITIUM HYDRIDE BED DEVELOPMENT PART I DESIGN AND FABRICATION  

SciTech Connect (OSTI)

The Savannah River Site (SRS) tritium facilities have used 1{sup st} generation (Gen1) LaNi{sub 4.25}Al{sub 0.75} (LANA0.75) metal hydride storage beds for tritium absorption, storage, and desorption. The Gen1 design utilizes hot and cold nitrogen supplies to thermally cycle these beds. Second and 3{sup rd} generation (Gen2 and Gen3) storage bed designs include heat conducting foam and divider plates to spatially fix the hydride within the bed. For thermal cycling, the Gen2 and Gen 3 beds utilize internal electric heaters and glovebox atmosphere flow over the bed inside the bed external jacket for cooling. The currently installed Gen1 beds require replacement due to tritium aging effects on the LANA0.75 material, and cannot be replaced with Gen2 or Gen3 beds due to different designs of these beds. At the end of service life, Gen1 bed desorption efficiencies are limited by the upper temperature of hot nitrogen supply. To increase end-of-life desorption efficiency, the Gen1 bed design was modified, and a Thermal Enhancement Cartridge Heater Modified (TECH Mod) bed was developed. Internal electric cartridge heaters in the new design to improve end-of-life desorption, and also permit in-bed tritium accountability (IBA) calibration measurements to be made without the use of process tritium. Additional enhancements implemented into the TECH Mod design are also discussed.

Klein, J.; Estochen, E.

2014-03-06T23:59:59.000Z

125

Composite Materials for Hazard Mitigation of Reactive Metal Hydrides.  

SciTech Connect (OSTI)

In an attempt to mitigate the hazards associated with storing large quantities of reactive metal hydrides, polymer composite materials were synthesized and tested under simulated usage and accident conditions. The composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride. Composites with vinyl-containing siloxane oligomers were also polymerized with and without added styrene and divinyl benzene. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride reduced the inherent hydrogen storage capacity of the material. The composites were found to be initially effective at reducing the amount of heat released during oxidation. However, upon cycling the composites, the mitigating behavior was lost. While the polymer composites we investigated have mitigating potential and are physically robust, they undergo a chemical change upon cycling that makes them subsequently ineffective at mitigating heat release upon oxidation of the metal hydride. Acknowledgements The authors would like to thank the following people who participated in this project: Ned Stetson (U.S. Department of Energy) for sponsorship and support of the project. Ken Stewart (Sandia) for building the flow-through calorimeter and cycling test stations. Isidro Ruvalcaba, Jr. (Sandia) for qualitative experiments on the interaction of sodium alanate with water. Terry Johnson (Sandia) for sharing his expertise and knowledge of metal hydrides, and sodium alanate in particular. Marcina Moreno (Sandia) for programmatic assistance. John Khalil (United Technologies Research Corp) for insight into the hazards of reactive metal hydrides and real-world accident scenario experiments. Summary In an attempt to mitigate and/or manage hazards associated with storing bulk quantities of reactive metal hydrides, polymer composite materials (a mixture of a mitigating polymer and a metal hydride) were synthesized and tested under simulated usage and accident conditions. Mitigating the hazards associated with reactive metal hydrides during an accident while finding a way to keep the original capability of the active material intact during normal use has been the focus of this work. These composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride, in this case a prepared sodium alanate (chosen as a representative reactive metal hydride). It was found that the polymerization of styrene and divinyl benzene could be initiated using AIBN in toluene at 70 degC. The resulting composite materials can be either hard or brittle solids depending on the cross-linking density. Thermal decomposition of these styrene-based composite materials is lower than neat polystyrene indicating that the chemical nature of the polymer is affected by the formation of the composite. The char-forming nature of cross-linked polystyrene is low and therefore, not an ideal polymer for hazard mitigation. To obtain composite materials containing a polymer with higher char-forming potential, siloxane-based monomers were investigated. Four vinyl-containing siloxane oligomers were polymerized with and without added styrene and divinyl benzene. Like the styrene materials, these composite materials exhibited thermal decomposition behavior significantly different than the neat polymers. Specifically, the thermal decomposition temperature was shifted approximately 100 degC lower than the neat polymer signifying a major chemical change to the polymer network. Thermal analysis of the cycled samples was performed on the siloxane-based composite materials. It was found that after 30 cycles the siloxane-containing polymer composite material has similar TGA/DSC-MS traces as the virgin composite material indicating that the polymer is physically intact upon cycling. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride in the form of a composite material reduced the inherent hydrogen storage capacity of the material. This

Pratt, Joseph William; Cordaro, Joseph Gabriel; Sartor, George B.; Dedrick, Daniel E.; Reeder, Craig L.

2012-02-01T23:59:59.000Z

126

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

127

Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser fields: An ab initio self-interaction-free time-dependent density-functional approach  

E-Print Network [OSTI]

We present an ab initio nonpertubative investigation of the mechanisms responsible for the production of very-high-order harmonic generation (HHG) from Ar atoms and Ar+ ions by means of the self-interaction-free time-dependent density...

Carrera, Juan J.; Chu, Shih-I; Tong, X. M.

2005-06-21T23:59:59.000Z

128

High-Spin Cobalt Hydrides for Catalysis  

SciTech Connect (OSTI)

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

129

HYDROGEN STORAGE USINGHYDROGEN STORAGE USING COMPLEX HYDRIDESCOMPLEX HYDRIDES  

E-Print Network [OSTI]

, Michael D. HamptonDarlene K. Slattery, Michael D. Hampton FL Solar Energy Center, U. of Central FLFL Solar Energy Center, U. of Central FL #12;Objective · Identify a hydrogen storage system that meets the DOEHYDROGEN STORAGE USINGHYDROGEN STORAGE USING COMPLEX HYDRIDESCOMPLEX HYDRIDES Darlene K. Slattery

130

Dynamics of oxygen Rydberg atom generation following O 1s inner-shell excitation of H{sub 2}O  

SciTech Connect (OSTI)

The emission of low-energy electrons from H{sub 2}O has been investigated at photon excitation energies in the vicinity of the O 1s ionization threshold. Neutral oxygen Rydberg atoms (O*) were found to form, and the correlation between the initial inner-shell excited state of H{sub 2}O and the Rydberg state of O* was determined. The initially excited electron in a Rydberg orbital is shown to remain associated with O* even after the cleavage of two O-H bonds. We also show that the energy discrepancy between two Rydberg states of H{sub 2}O and O* can be explained by the influence of the post-collision interaction, which becomes stronger as the excitation energy approaches the 1s ionization threshold.

Gejo, T., E-mail: gejo@sci.u-hyogo.ac.jp; Ikegami, T.; Honma, K. [University of Hyogo, Koto 3-2-1, Kamigori-cho, Ako-gun, Hyogo 678-1297 (Japan); Takahashi, O. [Hiroshima University, 2-2 Kagamiyama 1-chome, Higashihiroshima 739-8512 (Japan); Shigemasa, E. [UVSOR Facility, Institute for Molecular Science, 38 Nishigo-Naka, Myodaiji, Okazaki 444-8585 (Japan); Hikosaka, Y. [Department of Environmental Science, Niigata University, 8050, Ikarashi 2-no-cho, Nishi-ku, Niigata 950-2181 (Japan); Tamenori, Y. [JASRI, Koto 1-1-1, Sayo-cho, Hyogo 679-5198 (Japan)

2014-06-07T23:59:59.000Z

131

Design of a rural water provision system to decrease arsenic exposure in Bangladesh  

E-Print Network [OSTI]

Hydride Generation Atomic Absorption Spectrophotomery (HG-Graphite Furnace Atomic Absorption Spectrometry (GF-Graphite Furnace - Atomic Absorption Spectroscopy (GF-AAS),

Mathieu, Johanna

2009-01-01T23:59:59.000Z

132

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

SciTech Connect (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

133

Preparation and X-Ray diffraction studies of curium hydrides  

SciTech Connect (OSTI)

Curium hydrides were prepared by reaction of curium-248 metal with hydrogen and characterized by X-ray powder diffraction. Several of the syntheses resulted in a hexagonal compound with average lattice parameters of a/sub 0/ = 0.3769(8) nm and c/sub 0/ = 0.6732(12) nm. These products are considere to be CmH/sub 3//sup -//sub 8/ by analogy with the behavior of lanthanide-hydrogen and lighter actinide-hydrogen systems. Face-centered cubic products with an average lattice parameter of a/sub 0/ = 0.5322(4) nm were obtained from other curium hydride preparations. This parameter is slightly smaller than that reported previously for cubic curium dihydride, CmH /SUB 2-x/ (B.M. Bansal and D. Damien. Inorg. Nucl. Chem. Lett. 6 603, 1970). The present results established a continuation of typical heavy trivalent lanthanidelike behavior of the transuranium actinide-hydrogen systems through curium.

Gibson, J.K.; Maire, R.G.

1985-10-01T23:59:59.000Z

134

ALUMINUM HYDRIDE: A REVERSIBLE STORAGE MATERIAL FOR HYDROGEN STORAGE  

SciTech Connect (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

135

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

136

LANL/PNNL Virtual Center for Chemical Hydrides and New Concepts...  

Broader source: Energy.gov (indexed) [DOE]

LANLPNNL Virtual Center for Chemical Hydrides and New Concepts for Hydrogen Storage * Thermodynamics * Kinetics * Recycle * WeightVolume Capacity * Durability Investigate...

137

E-Print Network 3.0 - aluminum hydride phases Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The nonlinear coupled dierential equations... enhancement by the aluminum sheets and the optimization of the operation of hydride bed are examined... It consists of a quantity...

138

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

SciTech Connect (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

139

Combined on-board hydride slurry storage and reactor system and process for hydrogen-powered vehicles and devices  

DOE Patents [OSTI]

An on-board hydride storage system and process are described. The system includes a slurry storage system that includes a slurry reactor and a variable concentration slurry. In one preferred configuration, the storage system stores a slurry containing a hydride storage material in a carrier fluid at a first concentration of hydride solids. The slurry reactor receives the slurry containing a second concentration of the hydride storage material and releases hydrogen as a fuel to hydrogen-power devices and vehicles.

Brooks, Kriston P; Holladay, Jamelyn D; Simmons, Kevin L; Herling, Darrell R

2014-11-18T23:59:59.000Z

140

Production of Hydrogen by Electrocatalysis: Making the H-H Bond by Combining Protons and Hydrides  

SciTech Connect (OSTI)

Generation of hydrogen by reduction of two protons by two electrons can be catalysed by molecular electrocatalysts. Determination of the thermodynamic driving force for elimination of H2 from molecular complexes is important for the rational design of molecular electrocatalysts, and allows the design of metal complexes of abundant, inexpensive metals rather than precious metals (“Cheap Metals for Noble Tasks”). The rate of H2 evolution can be dramatically accelerated by incorporating pendant amines into diphosphine ligands. These pendant amines in the second coordination sphere function as protons relays, accelerating intramolecular and intermolecular proton transfer reactions. The thermodynamics of hydride transfer from metal hydrides and the acidity of protonated pendant amines (pKa of N-H) contribute to the thermodynamics of elimination of H2; both of the hydricity and acidity can be systematically varied by changing the substituents on the ligands. A series of Ni(II) electrocatalysts with pendant amines have been developed. In addition to the thermochemical considerations, the catalytic rate is strongly influenced by the ability to deliver protons to the correct location of the pendant amine. Protonation of the amine endo to the metal leads to the N-H being positioned appropriately to favor rapid heterocoupling with the M-H. Designing ligands that include proton relays that are properly positioned and thermodynamically tuned is a key principle for molecular electrocatalysts for H2 production as well as for other multi-proton, multi-electron reactions important for energy conversions. The research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Pacific Northwest National Laboratory is operated by Battelle for DOE.

Bullock, R. Morris; Appel, Aaron M.; Helm, Monte L.

2014-03-25T23:59:59.000Z

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.


141

Elastic modulus mapping of atomically thin film based Lithium Ion Battery electrodes Lithium Ion Batteries (LIB) are one of the most promising class of next generation energy storage devices,  

E-Print Network [OSTI]

Batteries (LIB) are one of the most promising class of next generation energy storage devices, which canElastic modulus mapping of atomically thin film based Lithium Ion Battery electrodes Lithium Ion the charging/discharging which otherwise lead to in efficient battery operation. The cyclically charging

142

Solid-State Gadolinium-Magnesium Hydride Optical Switch R. Armitage  

E-Print Network [OSTI]

-state electrochromic device. With positive polarization of the hydride electrode, the visible reflectance approaches 35 and reflecting states. Keywords: gadolinium-magnesium; electrochromic hydride; optical switching device. 2 #12;A conventional electrochromics5 . Optical switching has also been demonstrated by varying the H content

143

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

144

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

E-Print Network [OSTI]

..................................................................................................... 40 Figure 15 Formation of zirconium hydride as a function of temperature................ 44 Figure 16 Time dependence of hydrogen pickup with Avrami correlation............. 50 Figure 17 Time dependence of hydrogen pickup with parabolic... rate study....................................................... 43 Table 8 Results of rate study using Avrami equation .......................................... 50 Table 9 Constants for parabolic hydride rate...

Parkison, Adam Joseph

2009-05-15T23:59:59.000Z

145

Comparative analysis of the high-order harmonic generation in the laser ablation plasmas prepared on the surfaces of complex and atomic targets  

SciTech Connect (OSTI)

We analyzed high-order harmonic generation from the plasma plumes prepared on the surfaces of complex targets. The studies of In-Ag targets showed that the characteristics of the high-order harmonics from the double-target plume were the same as those from the single-target plasmas. For the chromium-tellurium plasma, the enhancements of the 29th and 27th harmonics were obtained, thus indicating the appearance of the enhancement properties from both components of the double-target plasma. These comparative studies also showed higher enhancement of a single harmonic in the case of atomic plasma (Sb) with regard to the molecular one (InSb). The additional component can only decrease the enhancement factor of the medium, due to the change of the oscillator strength and spectral distribution of the transitions involved in the resonance enhancement of the specific harmonic order. The theoretical calculations have shown the enhancement of specific harmonics for the Sb, Te, and Cr plasmas in the double-target configurations.

Ganeev, R. A. [Scientific Association Akadempribor, Academy of Sciences of Uzbekistan, Akademgorodok, Tashkent 100125 (Uzbekistan); Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Milosevic, D. B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Strasse 2a, 12489 Berlin (Germany)

2008-07-15T23:59:59.000Z

146

Getting metal-hydrides to do what you want them to  

SciTech Connect (OSTI)

With the discovery of AB/sub 5/ compounds, intermetallic hydrides with unusual properties began to be developed (H dissociation pressures of one to several atmospheres, extremely rapid and reversible adsorption/desorption very large amounts of H adsorbed). This paper reviews the factors that must be controlled in order to modify these hydrides to make them useful. The system LaNi/sub 5/ + H/sub 2/ is used as example. Use of AB/sub 5/ hydrides to construct a chemical heat pumps is discussed. Results of a systematic study substituting Al for Ni are reported; the HYCSOS pump is described briefly. Use of hydrides as hydrogen getters (substituted ZrV/sub 2/) is also discussed. Finally, possible developments in intermetallic hydride research in the 1980's and the hydrogen economy are discussed. 10 figures. (DLC)

Gruen, D.M.

1981-01-01T23:59:59.000Z

147

ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE  

SciTech Connect (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

148

ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE  

SciTech Connect (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

149

Chemical Hydrides for Hydrogen Storage in Fuel Cell Applications  

SciTech Connect (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

150

Working with SRNL - Our Facilities - Metal Hydride Laboratories  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched FerromagnetismWaste and MaterialsWenjun1 Table 1.14Working WithGloveboxMetal Hydride

151

Modeling of temporal behavior of isotopic exchange between gaseous hydrogen and palladium hydride power  

SciTech Connect (OSTI)

A parametric rate-equation model is described which depicts the time dependent behavior of the isotopic exchange process occurring between the solid and gas phases in gaseous hydrogen (deuterium) flows through packed-powder palladium deuteride (hydride) beds. The exchange mechanism is assumed to be rate-limited by processes taking place on the surface of the powder. The fundamental kinetic parameter of the model is the isotopic exchange probability, p, which is the probability that an isotopic exchange event occurs during a collision of a gas phase atom with the surface. Isotope effects between the gas and solid phases are explicitly included in terms of the isotope separation factor, ..cap alpha... Results of the model are compared with recent experimental measurements of isotope exchange in the ..beta..-phase hydrogen/palladium system and, using a literature value of ..cap alpha.. = 2.4, a good description of the experimental data is obtained for p approx. 10/sup -7/. In view of the importance of the isotope effects in the hydrogen/palladium system and the range of ..cap alpha.. values reported for the ..beta..-phase in the literature, the sensitivity of the model results to a variation in the value of ..cap alpha.. is examined.

Melius, C F; Foltz, G W

1987-01-01T23:59:59.000Z

152

GAS-PHASE REACTIONS OF HYDRIDE ANION, H{sup -}  

SciTech Connect (OSTI)

Rate constants were measured at 300 K for the reactions of the hydride anion, H{sup -}, with neutral molecules C{sub 2}H{sub 2}, H{sub 2}O, CH{sub 3}CN, CH{sub 3}OH, (CH{sub 3}){sub 2}CO, CH{sub 3}CHO, N{sub 2}O, CO{sub 2}, O{sub 2}, CO, CH{sub 3}Cl, (CH{sub 3}){sub 3}CCl, (CH{sub 3}CH{sub 2}){sub 2}O, C{sub 6}H{sub 6}, and D{sub 2} using a flowing-afterglow instrument. Experimental work was supplemented by ab initio calculations to provide insight into the viability of reaction pathways. Our reported rate constants should prove useful to models of astrophysical environments where conditions prevail for the existence of both H{sup -} and neutral species. The variety of neutral reactants studied includes representative species from prototypical chemical groups, effectively mapping reactivity trends for the hydride anion.

Martinez, Oscar; Yang Zhibo; Demarais, Nicholas J.; Bierbaum, Veronica M. [Department of Chemistry and Biochemistry, 215 UCB, University of Colorado, Boulder, CO 80309-0215 (United States); Snow, Theodore P., E-mail: Oscar.Martinez@colorado.ed, E-mail: Zhibo.Yang@colorado.ed, E-mail: Nicholas.Demarais@colorado.ed, E-mail: Veronica.Bierbaum@colorado.ed, E-mail: Theodore.Snow@colorado.ed [Department of Astrophysical and Planetary Sciences, 391 UCB, University of Colorado, Boulder, CO 80309-0391 (United States)

2010-09-01T23:59:59.000Z

153

Microstructure and hydriding studies of AB/sub 5/ hydrogen storage compounds. Final report  

SciTech Connect (OSTI)

New data on the microstructure, pressure-composition-temperature, and absorption/desorption kinetics of AB/sub 5/ metal hydrides are presented. The most significant result to emerge from the investigation is that many of the AB/sub 5/ metal hydrides, especially the LaNi/sub 5/ related materials, show instantaneous absorption and desorption response in proportion to the amount of cooling or heating which is provided. Eight categories of materials were studied: reference alloys (LaNi/sub 5/, LaNi/sub 4/ /sub 9/Al/sub 0/ /sub 1/, LaNi/sub 3/Co/sub 2/); Ni second phase particles (LaNi/sub 5/ /sub 67/, LaNi/sub 7/, LaNi/sub 11/ /sub 3/); eutectoid microstructure (SmCo/sub 5/); other second phases (LaNi/sub 3/ /sub 8/Fe/sub 1/ /sub 2/, LaNi/sub 3/ /sub 5/Cr/sub 1/ /sub 5/, LaNi/sub 4/Cr, LaNi/sub 4/Si; LaNi/sub 4/Sn, MNi/sub 4/Sn, MNi/sub 4/ /sub 3/Al/sub 0/ /sub 7/); substitutional elements (LaNi/sub 4/Cu, LaNi/sub 4/ /sub 5/Pd/sub 0/ /sub 5/, LaNi/sub 4/ /sub 7/Sn/sub 0/ /sub 3/, LaNi/sub 4/ /sub 8/C/sub 0/ /sub 2/, MNi/sub 4/ /sub 3/Mn/sub 0/ /sub 7/); surface active elements (LaNi/sub 4/ /sub 8/B/sub 0/ /sub 2/, LaNi/sub 4/ /sub 9/S/sub 0/ /sub 1/, LaNi/sub 4/ /sub 9/Se/sub 0/ /sub 1/); large diameter atom substitutions (Mg/sub 0/ /sub 1/La/sub 0/ /sub 9/Ni/sub 5/, Ca/sub 0/ /sub 2/La/sub 0/ /sub 8/Ni/sub 5/, Sr/sub 0/ /sub 2/La/sub 0/ /sub 8/Ni/sub 5/, Ba/sub 0/ /sub 2/La/sub 0/ /sub 8/Ni/sub 5/); other compositions (LaNi/sub 3/); and Pd plating (electroless plated samples and mechanically alloyed specimens).

Goodell, P.D.; Sandrock, G.D.; Huston, E.L.

1980-01-01T23:59:59.000Z

154

Atomic magnetometer  

DOE Patents [OSTI]

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

155

Final report for the DOE Metal Hydride Center of Excellence.  

SciTech Connect (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

156

Photogeneration of Hydride Donors and Their Use Toward CO2 Reduction  

SciTech Connect (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

157

Complex Hydride Compounds with Enhanced Hydrogen Storage Capacity  

SciTech Connect (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 150°C. 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

158

Documentation of Hybrid Hydride Model for Incorporation into Moose-Bison and Validation Strategy  

SciTech Connect (OSTI)

This report documents the development, demonstration and validation of a mesoscale, microstructural evolution model for simulation of zirconium hydride ?-ZrH1.5 precipitation in the cladding of used nuclear fuels that may occur during long-term dry storage. While the Zr-based claddings are manufactured free of any hydrogen, they absorb hydrogen during service, in the reactor by a process commonly termed ‘hydrogen pick-up’. The precipitation and growth of zirconium hydrides during dry storage is one of the most likely fuel rod integrity failure mechanisms either by embrittlement or delayed hydride cracking of the cladding (Hanson et al., 2011). While the phenomenon is well documented and identified as a potential key failure mechanism during long-term dry storage (Birk et al., 2012 and NUREG/CR-7116), the ability to actually predict the formation of hydrides is poor. The model being documented in this work is a computational capability for the prediction of hydride formation in different claddings of used nuclear fuels. This work supports the Used Fuel Disposition Research and Development Campaign in assessing the structural engineering performance of the cladding during and after long-term dry storage. In this work, a model to numerically simulate hydride precipitation at the microstructural scale, in a wide variety of Zr-based claddings, under dry-storage conditions is being developed. It will be used to aid in the evaluation of the mechanical integrity of used fuel rods during dry storage and transportation by providing the structural conditions from the microstructural scale to the continuum scale to engineering component scale models to predict if the used fuel rods will perform without failure under normal and off-normal conditions. The microstructure, especially, the hydride structure is thought to be a primary determinant of cladding failure, thus this component of UFD’s storage and transportation analysis program is critical. The model development, application and validation of the model are documented and the limitations of the current model are discussed. The model has been shown to simulate hydride precipitation in Zircaloy-4 cladding with correct morphology, thermodynamics and kinetics. An unexpected insight obtained from simulations hydride formation in Zircaloy-4 is that small (sub-micron) precipitates need to order themselves to form the larger hydrides typically described as radially-reoriented precipitates. A limitation of this model is that it does not currently solve the stress state that forms dynamically in the precipitate or matrix surrounding the precipitate. A method to overcome the limitations is suggested and described in detail. The necessary experiments to provide key materials physics and to validate the model are also recommended.

Veena Tikare; Philippe Weck; Peter Schultz; Blythe Clark; John Mitchell; Michael Glazoff; Eric Homer

2014-10-01T23:59:59.000Z

159

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 (OSTI)

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

160

Hadronic Atoms  

E-Print Network [OSTI]

We review the theory of hadronic atoms in QCD+QED. The non-relativistic effective Lagrangian approach, used to describe this type of bound states, is illustrated with the case of pi+pi- atoms. In addition, we discuss the evaluation of isospin-breaking corrections to hadronic atom observables by invoking chiral perturbation theory.

J. Gasser; V. E. Lyubovitskij; A. Rusetsky

2009-03-02T23:59:59.000Z

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

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.

162

Incorporation of Hydride Nuclear Fuels in Commercial Light Water Reactors  

E-Print Network [OSTI]

electricity generation capacity and operating efficiency of nuclear plants [Nuclear Plant Capacity Factor Nuclear Electricity Generationelectricity generation capacity and operating efficiency of nu- clear plants [

Terrani, Kurt Amir

2010-01-01T23:59:59.000Z

163

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

E-Print Network [OSTI]

atmosphere to reduce sample oxidation .................................................................................................. 13 12 Aluminum oxide crucible located at the bottom of the hydride-dehydride rig. ... 14 13 Furnace and furnace... at 60 minutes, 5psig, 250?C hydride, 325?C dehydride ................................................................................................... 30 27 Rotary kiln designed at ORNL for use in voloxidation...

Sames, William

2011-08-08T23:59:59.000Z

164

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

SciTech Connect (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

165

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

SciTech Connect (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

166

Process for production of an aluminum hydride compound  

DOE Patents [OSTI]

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

167

A mechanistic study of aryl halide reactions with lithium aluminum hydride  

E-Print Network [OSTI]

A M:"CHA~JISTIC STUDv OF ARYL HALID RHAC IC~JS ' ITH LITHIUM ALUM 'J"M HYDRIDE A Thesis FU-FAJJ CHUI'JG Submitted to the Graduate College of Texas ARM University in nartial fulfillment of the reauirement for the degree of MASTER OF SCI- JC... of this stud!y :a to investigate possibility o f a. fr ee r a . 1 ca machina=--. by;;h:ch ". thium alum'num hydride may reduce organic ccmnounds. evzcus results have irdicated that thc reductior of o-allylcxy- 'oenzene diazonium icn by . ributyltin hydrioe...

Chung, Fu-Fan

1980-01-01T23:59:59.000Z

168

Method and composition in which metal hydride particles are embedded in a silica network  

DOE Patents [OSTI]

A silica embedded metal hydride composition and a method for making such a composition. The composition is made via the following process: A quantity of fumed silica is blended with water to make a paste. After adding metal hydride particles, the paste is dried to form a solid. According to one embodiment of the invention, the solid is ground into granules for use of the product in hydrogen storage. Alternatively, the paste can be molded into plates or cylinders and then dried for use of the product as a hydrogen filter. Where mechanical strength is required, the paste can be impregnated in a porous substrate or wire network.

Heung, Leung K. (Aiken, SC)

1999-01-01T23:59:59.000Z

169

Quantum-fluid-dynamics approach for strong-field processes: Application to the study of multiphoton ionization and high-order harmonic generation of He and Ne atoms  

E-Print Network [OSTI]

of the hydrodynamical density and wave function in space and time. The procedure is applied to the study of multiphoton for Ne, good agreement is achieved. Four different exchange-correlation energy functionals are used systems. Among these novel high-intensity phenomena, multiple high-order har- monic generation HHG

Chu, Shih-I

170

Coherent Atom Optics with fast metastable rare gas atoms  

SciTech Connect (OSTI)

Coherent atom optics experiments making use of an ultra-narrow beam of fast metastable atoms generated by metastability exchange are reported. The transverse coherence of the beam (coherence radius of 1.7 {mu}m for He*, 1.2 {mu}m for Ne*, 0.87 {mu}m for Ar*) is demonstrated via the atomic diffraction by a non-magnetic 2{mu}m-period reflection grating. The combination of the non-scalar van der Waals (vdW) interaction with the Zeeman interaction generated by a static magnetic field gives rise to ''vdW-Zeeman'' transitions among Zeeman sub-levels. Exo-energetic transitions of this type are observed with Ne*(3P2) atoms traversing a copper micro-slit grating. They can be used as a tunable beam splitter in an inelastic Fresnel bi-prism atom interferometer.

Grucker, J.; Baudon, J.; Karam, J.-C.; Perales, F.; Vassilev, G.; Ducloy, M. [Laboratoire de Physique des Lasers, Universite Paris 13, Avenue J.B. Clement, 93430-Villetaneuse (France); Bocvarski, V. [Institute of Physics, Pregrevica 118, 11080 - Belgrade-Zemun (Serbia and Montenegro)

2006-12-01T23:59:59.000Z

171

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

172

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

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, J.W.

1993-03-30T23:59:59.000Z

174

E-Print Network 3.0 - analysis-hydride generation-gas phase Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

on the high-pressure phase diagram of molecular CO2... of a new molecular phase of carbon dioxide at high-pressure and high- temperature. Using x-ray diffraction... , we...

175

Reversible Metal Hydride Thermal Energy Storage for High Temperature Power Generation Systems  

Broader source: Energy.gov [DOE]

This presentation was delivered at the SunShot Concentrating Solar Power (CSP) Program Review 2013, held April 23–25, 2013 near Phoenix, Arizona.

176

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

E-Print Network [OSTI]

Mathematical Modelling of a Metal Hydride Hydrogen Storage System by Brendan David MacDonald B of MASTER OF APPLIED SCIENCE in the Department of Mechanical Engineering © Brendan David MacDonald, 2006 Hydrogen Storage System by Brendan David MacDonald B.A.Sc., University of Waterloo, 2004 Supervisory

Victoria, University of

177

Friction Stir Welding of Hydrided Titanium Alloys Mark Taylor, D.P. Field  

E-Print Network [OSTI]

Friction Stir Welding of Hydrided Titanium Alloys Mark Taylor, D.P. Field Multi-Scale Engineering for Undergraduates program under grant number EEC-0754370 During Friction Stir Welding (FSW), a non-consumable tool-state welding process, much frictional heating and force is required of the tool. This steep demand on the tool

Collins, Gary S.

178

Hydrogen Internal Combustion Engine Two Wheeler with on-board Metal Hydride Storage  

E-Print Network [OSTI]

be obtained from sources such as electrolysis using low cost electricity, hydrogen as a by of cost- effective hydrogen in India (which we chose as a test case) is not a barrier. Thus, in the nearHydrogen Internal Combustion Engine Two Wheeler with on-board Metal Hydride Storage K. Sapru*, S

179

The influence of hydride blisters on the fracture of Zircaloy-4 O.N. Pierron a  

E-Print Network [OSTI]

.elsevier.com/locate/jnucmat Journal of Nuclear Materials 322 (2003) 21­35 #12;hydrogen embrittlement [15]. Such an effect becomes, and radiation damage [1]. As the cladding undergoes oxidation with the associated hydrogen pickup, the total amount of hydrogen increases, and hydride precipitates form pref- erentially near the outer (cooler

Motta, Arthur T.

180

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

Note: This page contains sample records for the topic "hydride generation atomic" from the National Library of EnergyBeta (NLEBeta).
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181

First Principles Studies of Phase Stability and Reaction Dynamics in Complex Metal Hydrides  

SciTech Connect (OSTI)

Complex metal hydrides are believed to be one of the most promising materials for developing hydrogen storage systems that can operate under desirable conditions. At the same time, these are also a class of materials that exhibit intriguing properties. We have used state-of-the-art computational techniques to study the fundamental properties of these materials.

Chou, Mei-Yin

2014-09-29T23:59:59.000Z

182

Complex Hydrides for Hydrogen Storage Darlene K. Slattery and Michael D. Hampton  

E-Print Network [OSTI]

at a temperature of less than 100 o C in order to be compatible with fuel cells and must have an installed hydrogen have reported the discovery of a number of catalysts that improve the reversing of the hydrogen release the hydrogenation/dehydrogenation of sodium aluminum hydride. Mechanical incorporation of the catalyst

183

Threat of Hydride Re-orientation to Spent Fuel Integrity During Transportation Accidents: Myth or Reality?  

SciTech Connect (OSTI)

The source-term study conducted by Sandia National Laboratories nearly two decades ago for the spent fuel inventory known at the time, which was in the low-to-medium burnup range ({approx}35 GWd/MTU), showed that the effects of transportation accidents on spent fuel failures, and consequential radioactivity release to the environment, were relatively benign. However, with today's discharged fuel burnups routinely greater than 45 GWd/MTU, potential hydride reorientation during interim dry storage, and its effects on cladding properties, has become one of the primary concerns for spent fuel transportation. Laboratory tests of un-irradiated cladding specimens subjected to heat treatments promoting hydride dissolution followed by re-precipitation in the radial direction have shown that relatively moderate concentrations ({approx}70 ppm) of radial hydrides can significantly degrade cladding ductility, at least at room temperature. The absence of specific data that are relevant to high-burnup spent fuel under dry storage conditions have led to the conjecture, deduced from those tests, that massive cladding failures, possibly resulting in fuel reconfiguration, can be expected during cask drop events. Such conclusions are not borne out by the findings in this paper. The analysis results indicate that cladding failure is bi-modal: a state of failure initiation at the cladding ID remaining as part-wall damage with less than 2% probability of occurrence, and a through-wall failure at a probability of 1 E-5. These results indicate that spent fuel conditions that could promote the formation of radial hydrides during dry storage are not sufficient to produce radial hydrides concentrations of significant levels to cause major threat to spent fuel integrity. It is important to note in this regard that the through-wall cladding failure probability of 1 E-5 is of the same order of magnitude as calculated in the cited Sandia study for low burnup fuel. (authors)

Rashid, Joe [ANATECH, 5435 Oberlin Drive, San Diego, CA 92121 (United States); Machiels, Albert [EPRI, 3420 Hillview Avenue, Palo Alto, CA 94304 (United States)

2007-07-01T23:59:59.000Z

184

Atom Interferometry  

ScienceCinema (OSTI)

Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton?s constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gryoscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be sued to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

Mark Kasevich

2010-01-08T23:59:59.000Z

185

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

186

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

SciTech Connect (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

187

Empirical and physics based mathematical models of uranium hydride decomposition kinetics with quantified uncertainties.  

SciTech Connect (OSTI)

Metal particle beds have recently become a major technique for hydrogen storage. In order to extract hydrogen from such beds, it is crucial to understand the decomposition kinetics of the metal hydride. We are interested in obtaining a a better understanding of the uranium hydride (UH3) decomposition kinetics. We first developed an empirical model by fitting data compiled from different experimental studies in the literature and quantified the uncertainty resulting from the scattered data. We found that the decomposition time range predicted by the obtained kinetics was in a good agreement with published experimental results. Secondly, we developed a physics based mathematical model to simulate the rate of hydrogen diffusion in a hydride particle during the decomposition. We used this model to simulate the decomposition of the particles for temperatures ranging from 300K to 1000K while propagating parametric uncertainty and evaluated the kinetics from the results. We compared the kinetics parameters derived from the empirical and physics based models and found that the uncertainty in the kinetics predicted by the physics based model covers the scattered experimental data. Finally, we used the physics-based kinetics parameters to simulate the effects of boundary resistances and powder morphological changes during decomposition in a continuum level model. We found that the species change within the bed occurring during the decomposition accelerates the hydrogen flow by increasing the bed permeability, while the pressure buildup and the thermal barrier forming at the wall significantly impede the hydrogen extraction.

Salloum, Maher N.; Gharagozloo, Patricia E.

2013-10-01T23:59:59.000Z

188

Gold Hydride Complexes DOI: 10.1002/anie.200803842  

E-Print Network [OSTI]

have been observed solely in the gas phase.[7] The N-heterocyclic carbene (NHC) ligand IPr (IPr= 1, dimeric [{(IPr)CuH}2], synthesized from [(IPr)CuCl] in two steps.[8] Since NHC ligands have been shown reactions. The reaction of the known compound [(IPr)AuCl][10] with sodium tert-butoxide generated [(IPr

Müller, Peter

189

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

190

Draft of M2 Report on Integration of the Hybrid Hydride Model into INL’s MBM Framework for Review  

SciTech Connect (OSTI)

This report documents the development, demonstration and validation of a mesoscale, microstructural evolution model for simulation of zirconium hydride {delta}-ZrH{sub 1.5} precipitation in the cladding of used nuclear fuels that may occur during long-term dry storage. While the Zr-based claddings are manufactured free of any hydrogen, they absorb hydrogen during service, in the reactor by a process commonly termed ‘hydrogen pick-up’. The precipitation and growth of zirconium hydrides during dry storage is one of the most likely fuel rod integrity failure mechanisms either by embrittlement or delayed hydride cracking of the cladding (Hanson et al., 2011). While the phenomenon is well documented and identified as a potential key failure mechanism during long-term dry storage (Birk et al., 2012 and NUREG/CR-7116), the ability to actually predict the formation of hydrides is poor. The model being documented in this work is a computational capability for the prediction of hydride formation in different claddings of used nuclear fuels. This work supports the Used Fuel Disposition Research and Development Campaign in assessing the structural engineering performance of the cladding during and after long-term dry storage. This document demonstrates a basic hydride precipitation model that is built on a recently developed hybrid Potts-phase field model that combines elements of Potts-Monte Carlo and the phase-field models (Homer et al., 2013; Tikare and Schultz, 2012). The model capabilities are demonstrated along with the incorporation of the starting microstructure, thermodynamics of the Zr-H system and the hydride formation mechanism.

Tikare, Veena; Weck, Philippe F.; Schultz, Peter A.; Clark, Blythe; Michael Glazoff; Eric Homer

2014-07-01T23:59:59.000Z

191

Study on generating of thermal neutron scattering cross sections for LiH  

SciTech Connect (OSTI)

LiH is designated as a promising moderator and shielding material because of its low density, high melting point and large fraction of H atoms. However, lack of the thermal neutron cross sections of LiH makes numerical calculation deviate from experimental data to some extent. As a result, it is necessary to study LiH thermal kernel effect. The phonon property of LiH has been investigated by first-principles calculations using the plane-wave pseudo potential method with CASTEP code. The scattering law and the thermal neutron scattering cross sections for Li and H have been generated using this distribution. The results have been compared with zirconium hydride data. The GASKET and NJOY/LEAPR codes have been used in the calculation of scattering law, whose results have been compared with the reference; the discrepancy mainly comes from phonon spectrums and its expansion. LEAPR had the capability to compute scattering through larger energy and momentum transfers than GASKET did. By studying LiH phonon spectrum and constructing the model of LiH thermal kernel and scattering matrix, the ACE format LiH thermal neutron cross sections for MCNP software could be made and used for reactor Neutronics calculation. (authors)

Wang, L.; Jiang, X.; Zhao, Z.; Chen, L. [Northwest Institute of Nuclear Technology, Xi'an 710024 (China)

2013-07-01T23:59:59.000Z

192

Isotope exchange kinetics in metal hydrides I : TPLUG model.  

SciTech Connect (OSTI)

A one-dimensional isobaric reactor model is used to simulate hydrogen isotope exchange processes taking place during flow through a powdered palladium bed. This simple model is designed to serve primarily as a platform for the initial development of detailed chemical mechanisms that can then be refined with the aid of more complex reactor descriptions. The one-dimensional model is based on the Sandia in-house code TPLUG, which solves a transient set of governing equations including an overall mass balance for the gas phase, material balances for all of the gas-phase and surface species, and an ideal gas equation of state. An energy equation can also be solved if thermodynamic properties for all of the species involved are known. The code is coupled with the Chemkin package to facilitate the incorporation of arbitrary multistep reaction mechanisms into the simulations. This capability is used here to test and optimize a basic mechanism describing the surface chemistry at or near the interface between the gas phase and a palladium particle. The mechanism includes reversible dissociative adsorptions of the three gas-phase species on the particle surface as well as atomic migrations between the surface and the bulk. The migration steps are more general than those used previously in that they do not require simultaneous movement of two atoms in opposite directions; this makes possible the creation and destruction of bulk vacancies and thus allows the model to account for variations in the bulk stoichiometry with isotopic composition. The optimization code APPSPACK is used to adjust the mass-action rate constants so as to achieve the best possible fit to a given set of experimental data, subject to a set of rigorous thermodynamic constraints. When data for nearly isothermal and isobaric deuterium-to-hydrogen (D {yields} H) and hydrogen-to-deuterium (H {yields} D) exchanges are fitted simultaneously, results for the former are excellent, while those for the latter show pronounced deviations at long times. These discrepancies can be overcome by postulating the presence of a surface poison such as carbon monoxide, but this explanation is highly speculative. When the method is applied to D {yields} H exchanges intentionally poisoned by known amounts of CO, the fitting results are noticeably degraded from those for the nominally CO-free system but are still tolerable. When TPLUG is used to simulate a blowdown-type experiment, which is characterized by large and rapid changes in both pressure and temperature, discrepancies are even more apparent. Thus, it can be concluded that the best use of TPLUG is not in simulating realistic exchange scenarios, but in extracting preliminary estimates for the kinetic parameters from experiments in which variations in temperature and pressure are intentionally minimized.

Larson, Rich; James, Scott Carlton; Nilson, Robert H.

2011-05-01T23:59:59.000Z

193

Measurement of stibine and arsine generation from the Exide 3100-Ah lead-acid module  

SciTech Connect (OSTI)

Stibine and arsine evolution from lead-acid cells in a 36-kWh Exide load-leveling module was measured as this module approached 1900 cycles of operation. A specially prepared gas-collection apparatus enabled us to determine the maximum and average rates for evolution of both toxic hydrides. Hydride generation began once the cell voltage exceeded 2.4 V. The maximum rate for arsine occurred just above 2.5 V and consistently preceded the peak rate for stibine for each sampled cell. When adjusted for size effects, the degree of stibine and arsine evolution was greater than found in a continuous overcharge study conducted by Exide. The average rates of hydride generation were found to be 175 ..mu..g/min for stibine and 12.6 ..mu..g/min for arsine. The former rate proved to be the critical value in determining safe ventilation requirements for cell off-gases. The minimum airflow requirement was calculated to be 340 L/min per cell. Projections for a hypothetical 1-MWh Exide battery without an abatement system indicated that the normal ventilation capacity in the Battery Energy Storage Test facility provides nearly five times the airflow needed for safe hydride removal.

Marr, J.J.; Smaga, J.A.

1987-01-01T23:59:59.000Z

194

Identification of a new pseudo-binary hydroxide during calendar corrosion of (La, Mg)2Ni7-type hydrogen storage alloys for Nickel-Metal Hydride batteries  

E-Print Network [OSTI]

hydrogen storage alloys for Nickel-Metal Hydride batteries J. Monnier 1 , H. Chen 1 , S. Joiret2,3 , J-MH batteries have been extensively studied during calendar storage and cycling [6-8]. In these alloys To improve the performances of Nickel-Metal Hydride batteries, an important step is the understanding

Boyer, Edmond

195

ReaxFFMgH Reactive Force Field for Magnesium Hydride Systems Sam Cheung, Wei-Qiao Deng, Adri C. T. van Duin, and William A. Goddard III*  

E-Print Network [OSTI]

ReaxFFMgH Reactive Force Field for Magnesium Hydride Systems Sam Cheung, Wei-Qiao Deng, Adri C. TFFMgH) for magnesium and magnesium hydride systems. The parameters for this force field were derived from fitting to quantum chemical (QM) data on magnesium clusters and on the equations of states for condensed phases

van Duin, Adri

196

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

SciTech Connect (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

197

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

SciTech Connect (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

198

Method and apparatus for storing hydrogen isotopes. [stored as uranium hydride in a block of copper  

DOE Patents [OSTI]

An improved method and apparatus for storing isotopes of hydrogen (especially tritium) are provided. The hydrogen gas is stored as hydrides of material (for example uranium) within boreholes in a block of copper. The mass of the block is critically important to the operation, as is the selection of copper, because no cooling pipes are used. Because no cooling pipes are used, there can be no failure due to cooling pipes. And because copper is used instead of stainless steel, a significantly higher temperature can be reached before the eutectic formation of uranium with copper occurs, (the eutectic of uranium with the iron in stainless steel forms at a significantly lower temperature).

McMullen, J.W.; Wheeler, M.G.; Cullingford, H.S.; Sherman, R.H.

1982-08-10T23:59:59.000Z

199

Metal hydrides as electrode/catalyst materials for oxygen evolution/reduction in electrochemical devices  

DOE Patents [OSTI]

An at least ternary metal alloy of the formula, AB.sub.(5-Y)X(.sub.y), is claimed. 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, and bismuth. 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.

Bugga, Ratnakumar V. (Arcadia, CA); Halpert, Gerald (Pasadena, CA); Fultz, Brent (Pasadena, CA); Witham, Charles K. (Pasadena, CA); Bowman, Robert C. (La Mesa, CA); Hightower, Adrian (Whittier, CA)

1997-01-01T23:59:59.000Z

200

Measurements of Ionic Structure in Shock Compressed Lithium Hydride from Ultrafast X-Ray Thomson Scattering  

SciTech Connect (OSTI)

We present the first ultrafast temporally, spectrally, and angularly resolved x-ray scattering measurements from shock-compressed matter. The experimental spectra yield the absolute elastic and inelastic scattering intensities from the measured density of free electrons. Laser-compressed lithium-hydride samples are well characterized by inelastic Compton and plasmon scattering of a K-alpha x-ray probe providing independent measurements of temperature and density. The data show excellent agreement with the total intensity and structure when using the two-species form factor and accounting for the screening of ion-ion interactions.

Kritcher, A. L. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Department of Nuclear Engineering, University of California Berkeley, Berkeley, California 94709 (United States); Neumayer, P.; Doeppner, T.; Landen, O. L.; Glenzer, S. H. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Brown, C. R. D. [Department of Physics, Imperial College, London SW7 2AZ (United Kingdom); AWE plc., Aldermaston, Reading, RG7 4PR (United Kingdom); Davis, P. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Department of Physics, University of California Berkeley, Berkeley, California 94709 (United States); Falcone, R. W.; Lee, H. J. [Department of Physics, University of California Berkeley, Berkeley, California 94709 (United States); Gericke, D. O.; Vorberger, J.; Wuensch, K. [CFSA, Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Gregori, G. [Department of Physics, Oxford University, Oxford OX1 3PU (United Kingdom); Holst, B.; Redmer, R. [Universitaet Rostock, Institut fuer Physik, D-18051 Rostock (Germany); Morse, E. C. [Department of Nuclear Engineering, University of California Berkeley, Berkeley, California 94709 (United States); Pelka, A.; Roth, M. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Darmstadt (Germany)

2009-12-11T23:59:59.000Z

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

CRADA (AL-C-2009-02) Final Report: Phase I. Lanthanum-based Start Materials for Hydride Batteries  

SciTech Connect (OSTI)

The purpose of Phase I of this work is to focus on developing a La-based start material for making nickel-metal (lanthanum)-hydride batteries based on our carbothermic-silicon process. The goal is to develop a protocol for the manufacture of (La{sub 1-x}R{sub x})(Ni{sub 1-y}M{sub y})(Si{sub z}), where R is a rare earth metal and M is a non-rare earth metal, to be utilized as the negative electrode in nickel-metal hydride (NiMH) rechargeable batteries.

Gschneidner, Jr., Karl [Ames Laboratory; Schmidt, Frederick [Ames Laboratory] [Ames Laboratory; Frerichs, A.E. [Ames Laboratory] [Ames Laboratory; Ament, Katherine A. [Ames Laboratory] [Ames Laboratory

2013-05-01T23:59:59.000Z

202

Theory of Hydride-Proton Transfer (HPT) Carbonyl Reduction by [Os(III)(tpy)(Cl)(NH=CHCH3)(NSAr)  

SciTech Connect (OSTI)

Quantum mechanical analysis reveals that carbonyl reduction of aldehydes and ketones by the imine-based reductant cis-[Os{sup III}(tpy)(Cl)(NH?CHCH{sub 3})(NSAr)] (2), which is accessible by reduction of the analogous nitrile, occurs by hydride-proton transfer (HPT) involving both the imine and sulfilimido ligands. In carbonyl reduction, water or alcohol is necessary to significantly lower the barrier for proton shuttling between ligands. The ?N(H)SAr group activates the carbonyl group through hydrogen bonding while the ?NC(H)CH{sub 3} ligand delivers the hydride.

Ess, Daniel H.; Schauer, Cynthia; Meyer, Thomas J.

2010-01-01T23:59:59.000Z

203

Single atom as a macroscopic entanglement source  

E-Print Network [OSTI]

by many authors including the generation of entangled coherent state #3;1?3#4;, single photon and vacuum entanglement #3;4#4;, and two-atom entanglement #3;5#4;. More recently, generation of macroscopic entangled states via phase sensitive... cascade configuration crossing or trapped in a two-mode field cavity. The atomic level configuration is depicted in Fig. 1. The two atomic transitions #5;a#6;? #5;b#6; and #5;b#6;? #5;c#6; interact with the two cavity modes with detunings #1...

Zhou, Ling; Xiong, Han; Zubairy, M. Suhail.

2006-01-01T23:59:59.000Z

204

Mechanical Behavior Studies of Depleted Uranium in the Presence of Hydrides  

SciTech Connect (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

205

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

SciTech Connect (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

206

Verification and Validation Strategy for Implementation of Hybrid Potts-Phase Field Hydride Modeling Capability in MBM  

SciTech Connect (OSTI)

The Used Fuel Disposition (UFD) program has initiated a project to develop a hydride formation modeling tool using a hybrid Potts­phase field approach. The Potts model is incorporated in the SPPARKS code from Sandia National Laboratories. The phase field model is provided through MARMOT from Idaho National Laboratory.

Jason D. Hales; Veena Tikare

2014-04-01T23:59:59.000Z

207

OBSERVATIONS IN REACTIVITY BETWEEN BH CONTAINING COMPOUNDS AND ORGANOMETALLIC REAGENTS: SYNTHESIS OF BORONIC ACIDS, BORONIC ESTERS, AND MAGNESIUM HYDRIDES  

E-Print Network [OSTI]

aryl bromides and H 2 BN(iPr) 2 Scheme 2.7. Hydroboration oftransfer hydride to BH 2 -N(iPr) 2 Scheme 2.10. Conversionchloride with BH 2 -N(iPr) 2 Scheme 3; Aqueous quench of p-

Clary, Jacob William

2012-01-01T23:59:59.000Z

208

Room-Temperature Metal-Hydride Discharge Source, with Observations on NiH and FeH Raphael Vallon,  

E-Print Network [OSTI]

Room-Temperature Metal-Hydride Discharge Source, with Observations on NiH and FeH Raphae¨l Vallon laser excitation and dispersed fluorescence spectra of NiH have also been recorded. The source has been are strong enough to record dispersed fluorescence from NiH by Fourier transform interferometry in magnetic

Ashworth, Stephen H.

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

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

2013-08-27T23:59:59.000Z

211

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

SciTech Connect (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

212

atom-atom collisions: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atomic Safronova, Marianna 3 Atom-atom correlations in colliding Bose-Einstein condensates Quantum Physics (arXiv) Summary: We analyze atom-atom correlations in the s-wave...

213

Metal Hydrides  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion | Department of EnergyDevelopmentTechnologies |Charles Page -toMetabolic PathwaysMetal

214

Neutral atom traps.  

SciTech Connect (OSTI)

This report describes progress in designing a neutral atom trap capable of trapping sub millikelvin atom in a magnetic trap and shuttling the atoms across the atom chip from a collection area to an optical cavity. The numerical simulation and atom chip design are discussed. Also, discussed are preliminary calculations of quantum noise sources in Kerr nonlinear optics measurements based on electromagnetically induced transparency. These types of measurements may be important for quantum nondemolition measurements at the few photon limit.

Pack, Michael Vern

2008-12-01T23:59:59.000Z

215

Startup and Operation of a Metal Hydride Based Isotope Separation Process  

SciTech Connect (OSTI)

Production scale separation of tritium from other hydrogen isotopes at the Savannah River Site (SRS) in Aiken, SC, has been accomplished by several methods. These methods include thermal diffusion (1957--1986), fractional absorption (1964--1968), and cryogenic distillation (1967-present). Most recently, the Thermal Cycling Absorption Process (TCAP), a metal hydride based hydrogen isotope separation system, began production in the Replacement Tritium Facility (RTF) on April 9, 1994. TCAP has been in development at the Savannah River Technology Center since 1980. The production startup of this semi-continuous gas chromatographic separation process is a significant accomplishment for the Savannah River Site and was achieved after years of design, development, and testing.

Scogin, J.H.; Poore, A.S.

1995-02-27T23:59:59.000Z

216

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

SciTech Connect (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

217

Quantum Simulation of Helium Hydride in a Solid-State Spin Register  

E-Print Network [OSTI]

\\emph{Ab initio} computation of molecular properties is one of the most promising applications of quantum computing. While this problem is widely believed to be intractable for classical computers, efficient quantum algorithms exist which have the potential to vastly accelerate research throughput in fields ranging from material science to drug discovery. Using a solid-state quantum register realized in a nitrogen-vacancy (NV) defect in diamond, we compute the bond dissociation curve of the minimal basis helium hydride cation, HeH$^+$. Moreover, we report an energy uncertainty (given our model basis) of the order of $10^{-14}$ Hartree, which is ten orders of magnitude below desired chemical precision. As NV centers in diamond provide a robust and straightforward platform for quantum information processing, our work provides several important steps towards a fully scalable solid state implementation of a quantum chemistry simulator.

Ya Wang; Florian Dolde; Jacob Biamonte; Ryan Babbush; Ville Bergholm; Sen Yang; Ingmar Jakobi; Philipp Neumann; Alán Aspuru-Guzik; James D. Whitfield; Jörg Wrachtrup

2014-05-12T23:59:59.000Z

218

Mechanistic Insights into Hydride Transfer for Catalytic Hydrogenation of CO2 with Cobalt Complexes  

SciTech Connect (OSTI)

The catalytic hydrogenation of CO2 to formate by Co(dmpe)2H can proceeds via direct hydride transfer or via CO2 coordination to Co followed by reductive elimination of formate. Both pathways have activation barriers consistent with experiment (~17.5 kcal/mol). Controlling the basicity of Co by ligand design is key to improve catalysis. The research by N.K., D.M.C. and A.M.A. was supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. The research by S.R. and M.D. was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for the DOE by Battelle.

Kumar, Neeraj; Camaioni, Donald M.; Dupuis, Michel; Raugei, Simone; Appel, Aaron M.

2014-08-21T23:59:59.000Z

219

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

220

7 -ATOMIC PROCESSES Atomic processes can be  

E-Print Network [OSTI]

1 7 - ATOMIC PROCESSES Atomic processes can be: 1. Scattering 2. Absorption/Thermal Emission scattering, although the results won't change much when this condition is relaxed. Absorption/Thermal Emission Free-free (continuum) ("Bremsstrahlung") Emission/Absorption #12;2 Bound-Bound & Bound

Sitko, Michael L.

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

7 -ATOMIC PROCESSES Atomic processes can be  

E-Print Network [OSTI]

1 7 - ATOMIC PROCESSES Atomic processes can be: 1. Scattering 2. Absorption/Thermal Emission scattering, although the results won't change much when this condition is relaxed. #12;2 Absorption/Thermal Emission Free-free (continuum) ("Bremsstrahlung") Emission/Absorption Bound-Bound & Bound-Free Processes

Sitko, Michael L.

222

Production of mesoscopic superpositions with ultracold atoms  

E-Print Network [OSTI]

We study mesoscopic superpositions of two component Bose-Einstein condensates. Atomic condensates, with long coherence times, are good systems in which to study such quantum phenomenon. We show that the mesoscopic superposition states can be rapidly generated in which the atoms dispersively interact with the photon field in a cavity. We also discuss the production of compass states which are generalized Schr\\"{o}dinger cat states. The physical realization of mesoscopic states is important in studying decoherence and precision measurement.

H. T. Ng

2007-07-16T23:59:59.000Z

223

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.

Widom, A; Larsen, L

2012-01-01T23:59:59.000Z

224

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

225

Generation of graph-state streams  

E-Print Network [OSTI]

We propose a protocol to generate a stream of mobile qubits in a graph state through a single stationary parent qubit and discuss two types of its physical implementation, namely, the generation of photonic graph states through an atom-like qubit and those of flying atoms through a cavity-mode photonic qubit. The generated graph states fall into an important class that can hugely reduce the resource requirement of fault-tolerant linear optics quantum computation, which was previously known to be far from realistic. In regard to the flying atoms, we also propose a heralded generation scheme, which allows for high-fidelity graph states even under the photon loss.

Daniel Ballester; Jaeyoon Cho; M. S. Kim

2010-12-08T23:59:59.000Z

226

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

227

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

228

Diophantine Generation,  

E-Print Network [OSTI]

Diophantine Generation, Horizontal and Vertical Problems, and the Weak Vertical Method Alexandra Shlapentokh Diophantine Sets, Definitions and Generation Diophantine Sets Diophantine Generation Properties of Diophantine Generation Diophantine Family of Z Diophantine Family of a Polynomial Ring Going Down Horizontal

Shlapentokh, Alexandra

229

Driven Ratchets for Cold Atoms  

E-Print Network [OSTI]

Brownian motors, or ratchets, are devices which "rectify" Brownian motion, i.e. they can generate a current of particles out of unbiased fluctuations. The ratchet effect is a very general phenomenon which applies to a wide range of physical systems, and indeed ratchets have been realized with a variety of solid state devices, with optical trap setups as well as with synthetic molecules and granular gases. The present article reviews recent experimental realizations of ac driven ratchets with cold atoms in driven optical lattices. This is quite an unusual system for a Brownian motor as there is no a real thermal bath, and both the periodic potential for the atoms and the fluctuations are determined by laser fields. Such a system allowed us to realize experimentally rocking and gating ratchets, and to precisely investigate the relationship between symmetry and transport in these ratchets, both for the case of periodic and quasiperiodic driving.

Renzoni, F

2011-01-01T23:59:59.000Z

230

Driven Ratchets for Cold Atoms  

E-Print Network [OSTI]

Brownian motors, or ratchets, are devices which "rectify" Brownian motion, i.e. they can generate a current of particles out of unbiased fluctuations. The ratchet effect is a very general phenomenon which applies to a wide range of physical systems, and indeed ratchets have been realized with a variety of solid state devices, with optical trap setups as well as with synthetic molecules and granular gases. The present article reviews recent experimental realizations of ac driven ratchets with cold atoms in driven optical lattices. This is quite an unusual system for a Brownian motor as there is no a real thermal bath, and both the periodic potential for the atoms and the fluctuations are determined by laser fields. Such a system allowed us to realize experimentally rocking and gating ratchets, and to precisely investigate the relationship between symmetry and transport in these ratchets, both for the case of periodic and quasiperiodic driving.

F. Renzoni

2011-12-05T23:59:59.000Z

231

Discovery of novel hydrogen storage materials: an atomic scale...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

several key capabilities to be effective: (i) accurate prediction of decomposition thermodynamics, (ii) prediction of crystal structures for unknown hydrides, and (iii) prediction...

232

E-Print Network 3.0 - atomic matter waves Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the matter-wave analog of optical... in this effort. Matter-Wave Interferometry with Cold Atoms Cold atoms make it possible to generate very small... their wavelike behavior....

233

E-Print Network 3.0 - atomic beam produced Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in the scattering of light by a condensate Summary: for the generation of directed beams of atoms and light. B C D E F G Laser Beam Light Atoms A Observation... ). However,...

234

Atomic oxygen flux determined by mixed-phase Ag/Ag2O deposition...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

oxygen flux determined by mixed-phase AgAg2O deposition. Atomic oxygen flux determined by mixed-phase AgAg2O deposition. Abstract: The flux of atomic oxygen generated in a...

235

Trends in the electron-phonon coupling parameter in some metallic hydrides  

SciTech Connect (OSTI)

We present an evaluation of the electron-phonon coupling parameter lambda, using the McMillan formalism, for several classes of stoichiometric mono- and dihydrides with a metallic underlying fcc structure. We calculate the electronic term eta and use experimental estimates for the phonon energies when available. We derive systematic trends concerning both contributions to eta stemming, respectively, from the metallic site M and the hydrogen site H. We show that eta/sub H/ is generally small, but it may become large if the Fermi energy is in the metal s-p band as in the filled d-band transition-metal (TM) hydrides such as PdH; eta/sub H/ may also be large when a metal-hydrogen antibonding band crosses the Fermi level, a case which happens in AlH and may happen for some unstable dihydrides. The metallic contribution eta/sub M/ is calculated to be small for all stable mono- and dihydrides like PdH, NiH, ZrH/sub 2/, NbH/sub 2/, etc., but nothing in principle prevents this contribution from becoming as large as in some pure TM, if one sweeps the Fermi level through the whole metallic d band. Good agreement with the available experimental data is obtained concerning the occurrence of superconductivity in the compounds considered.

Gupta, M.; Burger, J.P.

1981-12-15T23:59:59.000Z

236

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

SciTech Connect (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

237

Hydride vapor phase epitaxy and characterization of high-quality ScN epilayers  

SciTech Connect (OSTI)

The heteroepitaxial growth of ScN films was investigated on various substrates by hydride vapor phase epitaxy (HVPE). Single crystalline mirror-like ScN(100) and ScN(110) layers were successfully deposited on r- and m-plane sapphire substrates, respectively. Homogeneous stoichiometric films (N/Sc ratio 1.01?±?0.10) up to 40??m in thickness were deposited. Their mosaicity drastically improved with increasing the film thickness. The band gap was determined by optical methods to be 2.06?eV. Impurity concentrations including H, C, O, Si, and Cl were investigated through energy dispersive X-ray spectrometry and secondary ion mass spectrometry. As a result, it was found that the presence of impurities was efficiently suppressed in comparison with that of HVPE-grown ScN films reported in the past, which was possible thanks to the home-designed corrosion-free HVPE reactor. Room-temperature Hall measurements indicated that the residual free electron concentrations ranged between 10{sup 18}–10{sup 20}?cm{sup ?3}, which was markedly lower than the reported values. The carrier mobility increased monotonically with the decreasing in carrier concentration, achieving the largest value ever reported, 284?cm{sup 2}?V{sup ?1}?s{sup ?1} at n?=?3.7?×?10{sup 18}?cm{sup ?3}.

Oshima, Yuichi, E-mail: OSHIMA.Yuichi@nims.go.jp; Víllora, Encarnación G.; Shimamura, Kiyoshi [Environment and Energy Materials Research Division, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

2014-04-21T23:59:59.000Z

238

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

SciTech Connect (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 â?? LiAlH4 â??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 â?? 0.3 MgH2 â?? 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 â?? 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 â?? 0.3 MgH2 â?? 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 â?? LiBH4 â?? 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

239

Multiplicative Sets of Atoms.  

E-Print Network [OSTI]

??It is possible for an element to have both an atom factorization and a factorization that will always contain a reducible element. This leads us… (more)

Rand, Ashley Nicole

2013-01-01T23:59:59.000Z

240

Improved graphite furnace atomizer  

DOE Patents [OSTI]

A graphite furnace atomizer for use in graphite furnace atomic absorption spectroscopy is described wherein the heating elements are affixed near the optical path and away from the point of sample deposition, so that when the sample is volatilized the spectroscopic temperature at the optical path is at least that of the volatilization temperature, whereby analyteconcomitant complex formation is advantageously reduced. The atomizer may be elongated along its axis to increase the distance between the optical path and the sample deposition point. Also, the atomizer may be elongated along the axis of the optical path, whereby its analytical sensitivity is greatly increased.

Siemer, D.D.

1983-05-18T23:59:59.000Z

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.


241

Atomic Collapse Observed  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and professor of Physics at UC Berkeley. Nonrelativistic electrons orbiting a subcritical nucleus exhibit the traditional circular Bohr orbit of atomic physics. But when the...

242

Please cite this article in press as: Malen, J.A., et al., Thermal hydraulic design of a hydride-fueled inverted PWR core. Nucl. Eng. Des. (2009), doi:10.1016/j.nucengdes.2009.02.026  

E-Print Network [OSTI]

Please cite this article in press as: Malen, J.A., et al., Thermal hydraulic design of a hydride hydraulic design of a hydride-fueled inverted PWR core J.A. Malena, , N.E. Todreasb , P. Hejzlarb , P and its thermal hydraulic performance is compared to that of a standard rod bundle core design also fueled

Malen, Jonathan A.

2009-01-01T23:59:59.000Z

243

Gauge invariant hydrogen atom Hamiltonian  

E-Print Network [OSTI]

For quantum mechanics of a charged particle in a classical external electromagnetic field, there is an apparent puzzle that the matrix element of the canonical momentum and Hamiltonian operators is gauge dependent. A resolution to this puzzle is recently provided by us in [2]. Based on the separation of the electromagnetic potential into pure gauge and gauge invariant parts, we have proposed a new set of momentum and Hamiltonian operators which satisfy both the requirement of gauge invariance and the relevant commutation relations. In this paper we report a check for the case of the hydrogen atom problem: Starting from the Hamiltonian of the coupled electron, proton and electromagnetic field, under the infinite proton mass approximation, we derive the gauge invariant hydrogen atom Hamiltonian and verify explicitly that this Hamiltonian is different from the Dirac Hamiltonian, which is the time translation generator of the system. The gauge invariant Hamiltonian is the energy operator, whose eigenvalue is the energy of the hydrogen atom. It is generally time-dependent. In this case, one can solve the energy eigenvalue equation at any specific instant of time. It is shown that the energy eigenvalues are gauge independent, and by suitably choosing the phase factor of the time-dependent eigenfunction, one can ensure that the time-dependent eigenfunction satisfies the Dirac equation.

Wei-Min Sun; Xiang-Song Chen; Xiao-Fu Lu; Fan Wang

2010-06-22T23:59:59.000Z

244

A coupled transport and solid mechanics formulation with improved reaction kinetics parameters for modeling oxidation and decomposition in a uranium hydride bed.  

SciTech Connect (OSTI)

Modeling of reacting flows in porous media has become particularly important with the increased interest in hydrogen solid-storage beds. An advanced type of storage bed has been proposed that utilizes oxidation of uranium hydride to heat and decompose the hydride, releasing the hydrogen. To reduce the cost and time required to develop these systems experimentally, a valid computational model is required that simulates the reaction of uranium hydride and oxygen gas in a hydrogen storage bed using multiphysics finite element modeling. This SAND report discusses the advancements made in FY12 (since our last SAND report SAND2011-6939) to the model developed as a part of an ASC-P&EM project to address the shortcomings of the previous model. The model considers chemical reactions, heat transport, and mass transport within a hydride bed. Previously, the time-varying permeability and porosity were considered uniform. This led to discrepancies between the simulated results and experimental measurements. In this work, the effects of non-uniform changes in permeability and porosity due to phase and thermal expansion are accounted for. These expansions result in mechanical stresses that lead to bed deformation. To describe this, a simplified solid mechanics model for the local variation of permeability and porosity as a function of the local bed deformation is developed. By using this solid mechanics model, the agreement between our reacting bed model and the experimental data is improved. Additionally, more accurate uranium hydride oxidation kinetics parameters are obtained by fitting the experimental results from a pure uranium hydride oxidation measurement to the ones obtained from the coupled transport-solid mechanics model. Finally, the coupled transport-solid mechanics model governing equations and boundary conditions are summarized and recommendations are made for further development of ARIA and other Sandia codes in order for them to sufficiently implement the model.

Salloum, Maher N.; Shugard, Andrew D.; Kanouff, Michael P.; Gharagozloo, Patricia E.

2013-03-01T23:59:59.000Z

245

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

SciTech Connect (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

246

1. Generation 1 1. Generation  

E-Print Network [OSTI]

1. Generation 1 _________________________________________________________________________ 1. Generation Sound and vibrations or, in more general terms, oscillations of matter (solids or fluids) are generated in many different dynamic processes. The basic mechanisms which underlie these oscillations

Berlin,Technische Universität

247

Atomic dark matter  

SciTech Connect (OSTI)

We propose that dark matter is dominantly comprised of atomic bound states. We build a simple model and map the parameter space that results in the early universe formation of hydrogen-like dark atoms. We find that atomic dark matter has interesting implications for cosmology as well as direct detection: Weak-scale dark atoms can accommodate hyperfine splittings of order 100 keV, consistent with the inelastic dark matter interpretation of the DAMA data while naturally evading direct detection bounds. Moreover, protohalo formation can be suppressed below M{sub proto} ? 10{sup 3}–10{sup 6}M{sub s}un for weak scale dark matter due to Ion-Radiation and Ion-Atom interactions in the dark sector.

Kaplan, David E.; Krnjaic, Gordan Z.; Rehermann, Keith R.; Wells, Christopher M., E-mail: dkaplan@pha.jhu.edu, E-mail: gordan@pha.jhu.edu, E-mail: keith@pha.jhu.edu, E-mail: cwells13@pha.jhu.edu [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2686 (United States)

2010-05-01T23:59:59.000Z

248

Arsenic removal and stabilization by synthesized pyrite  

E-Print Network [OSTI]

hydride generation atomic absorption spectrometry method for measuring arsenic species (As(III), As(V)). The synthesized pyrite was applied to remove arsenic and its maximum capacity for arsenic removal was measured in batch adsorption experiments to be 3...

Song, Jin Kun

2009-05-15T23:59:59.000Z

249

Soil and Water Science Department University of Florida Phytoremediation of Arsenic Contaminated Sites: Feasibility and Optimization  

E-Print Network [OSTI]

- atomic fluorescence spectrometry and high performance liquid chromatography- inductively coupled plasma mass spectrometry, and scanning/transmission electron microscope equipped with energy dispersive x in the plant biomass will be accomplished using high performance liquid chromatography-hydride generation

Ma, Lena

250

Method and apparatus for atomic imaging  

DOE Patents [OSTI]

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

251

Optical imaging of Rydberg atoms .  

E-Print Network [OSTI]

??We present an experiment exploring electromagnetically induced transparency (EIT) in Rydberg atoms in order to observe optical nonlinearities at the single photon level. ??Rb atoms… (more)

Mazurenko, Anton

2012-01-01T23:59:59.000Z

252

Rydberg Atoms for Quantum Information.  

E-Print Network [OSTI]

??I examine interactions between ensembles of cold Rydberg atoms, and between Rydberg atoms and an intense, optical standing wave. Because of their strong electrostatic interactions,… (more)

Younge, Kelly Cooper

2010-01-01T23:59:59.000Z

253

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]

Thermal Gradient (ECH-TG) system has the ability to generate static 20°C to 120°C 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...

Kuhr, Samuel Houston

2012-10-19T23:59:59.000Z

254

Nitric Oxide Production from Surface Recombination of Oxygen and Nitrogen Atoms  

E-Print Network [OSTI]

of hypersonic reentry vehicles. In the Earth's atmosphere, oxygen and nitrogen atoms are generated in the shock1 Nitric Oxide Production from Surface Recombination of Oxygen and Nitrogen Atoms Dusan A. Pejakovi from the recombination of oxygen and nitrogen atoms on quartz. The experiments employ two-photon laser

Martín, Pino

255

Trapping cold atoms using surface-grown carbon nanotubes P. G. Petrov,1,* S. Machluf,1  

E-Print Network [OSTI]

Trapping cold atoms using surface-grown carbon nanotubes P. G. Petrov,1,* S. Machluf,1 S. Younis,1 atomic clouds into magnetic traps created by single-wall carbon nanotubes grown directly onto dielectric surfaces. We show that atoms may be captured for experimen- tally sustainable nanotube currents, generating

Joselevich, Ernesto

256

Determination of Tellurium by Atomic-absorption Spectroscopy with Electrothermal Atomisation  

E-Print Network [OSTI]

305 Determination of Tellurium by Atomic-absorption Spectroscopy with Electrothermal Atomisation at sub-microgram levels by atomic-absorption spectroscopy ,,'ith electrothermal atomisation after the e generation -atomic-absorption spectroscopy. The prior con- version of tellurium into hydrogen telluride

Canberra, University of

257

Polar intermetallic compounds of the silicon and arsenic family elements and their ternary hydrides and fluorides  

SciTech Connect (OSTI)

An investigation has been made on the effects of hydrogen and fluoride in the solid state chemistry of alkaline-earth and divalent rare-earth metal pnictide (Pn) and tetrelide (Tt) phases A{sub 5}(Pn,Tt,){sub 3}Z{sub x}, where A = Ca, Sr, Ba, Sm, Eu, Yb; Pn = As, Sb, Bi; Tt = Si, Ge, Sn, Pb and Z = H, F. Several trivalent rare-earth-metal pnictides, RE{sub 5}Pn{sub 3} (RE = Y, La, Gd, Tb, Dy, Ho, Er, Tm) and alkaline-earth-metal trielides, A{sub 5}Tr{sub 3}Z{sub x} (Tr = Ga, In, Tl) have been included in an effort to complete observed structural trends. Two main experimental techniques were followed throughout this work, (a) reactions in absence of hydrogen or under continuous high vacuum, and (b) reactions with binary metal hydrides, AH{sub x}, in closed containers. The results demonstrate that all the phases reported with the {beta}-Yb{sub 5}Sb{sub 3}-type structure in the A{sub 5}Pn{sub 3} systems are hydrogen-stabilized compounds. Reactions in absence of hydrogen lead to compounds with the Mn{sub 5}Si{sub 3}-type structure. The structure type {beta}-Yb{sub 5}Sb{sub 3} (= Ca{sub 5}SB{sub 3}F) was found to be characteristic of ternary systems and inaccurately associated with phases that form in the Y{sub 5}Bi{sub 3}-type. A new series of isomorphous Zintl compounds with the Ca{sub 16}Sb{sub 11}-type structure were prepared and studied as well. All the alkaline-earth-metal tetrelides, A{sub 5}Tt{sub 3}, that crystallize in the Cr{sub 5}B{sub 3}-type structure can be interstitially derivatized by hydrogen or fluoride. Binary and ternary compounds were characterized by Guinier powder patterns, single crystal X-ray and powder neutron diffraction techniques. In an effort to establish property-structure relationships, electrical resistivity and magnetic measurements were performed on selected systems, and the results were explained in terms of the Zintl concepts, aided by extended Hueckel band calculations.

Leon-Escamilla, E.A.

1996-10-17T23:59:59.000Z

258

Optical atomic magnetometer  

DOE Patents [OSTI]

An optical atomic magnetometers is provided operating on the principles of nonlinear magneto-optical rotation. An atomic vapor is optically pumped using linearly polarized modulated light. The vapor is then probed using a non-modulated linearly polarized light beam. The resulting modulation in polarization angle of the probe light is detected and used in a feedback loop to induce self-oscillation at the resonant frequency.

Budker, Dmitry; Higbie, James; Corsini, Eric P

2013-11-19T23:59:59.000Z

259

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

260

Atomic mass compilation 2012  

SciTech Connect (OSTI)

Atomic mass reflects the total binding energy of all nucleons in an atomic nucleus. Compilations and evaluations of atomic masses and derived quantities, such as neutron or proton separation energies, are indispensable tools for research and applications. In the last decade, the field has evolved rapidly after the advent of new production and measuring techniques for stable and unstable nuclei resulting in substantial ameliorations concerning the body of data and their precision. Here, we present a compilation of atomic masses comprising the data from the evaluation of 2003 as well as the results of new measurements performed. The relevant literature in refereed journals and reports as far as available, was scanned for the period beginning 2003 up to and including April 2012. Overall, 5750 new data points have been collected. Recommended values for the relative atomic masses have been derived and a comparison with the 2003 Atomic Mass Evaluation has been performed. This work has been carried out in collaboration with and as a contribution to the European Nuclear Structure and Decay Data Network of Evaluations.

Pfeiffer, B., E-mail: bpfeiffe@uni-mainz.de [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Venkataramaniah, K. [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India)] [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India); Czok, U. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)] [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); Scheidenberger, C. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany) [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)

2014-03-15T23:59:59.000Z

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

Standard Model tests with trapped radioactive atoms  

E-Print Network [OSTI]

We review the use of laser cooling and trapping for Standard Model tests, focusing on trapping of radioactive isotopes. Experiments with neutral atoms trapped with modern laser cooling techniques are testing several basic predictions of electroweak unification. For nuclear $\\beta$ decay, demonstrated trap techniques include neutrino momentum measurements from beta-recoil coincidences, along with methods to produce highly polarized samples. These techniques have set the best general constraints on non-Standard Model scalar interactions in the first generation of particles. They also have the promise to test whether parity symmetry is maximally violated, to search for tensor interactions, and to search for new sources of time reversal violation. There are also possibilites for exotic particle searches. Measurements of the strength of the weak neutral current can be assisted by precision atomic experiments using traps of small numbers of radioactive atoms, and sensitivity to possible time-reversal violating electric dipole moments can be improved.

J. A. Behr; G. Gwinner

2009-03-04T23:59:59.000Z

262

Educational Multiwavelength Atomic Emission Spectrometer  

E-Print Network [OSTI]

atomic absorption is the capability for simultaneous multielement analysis. It can be used colleges had acquired atomic absorption instruments by the year 1990.[2] In contrast, atomic emission with the acetylene-air flame source taken from an existing atomic absorption instrument. Two spectrometer units

Nazarenko, Alexander

263

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

SciTech Connect (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

264

Atomic Force Microscope  

SciTech Connect (OSTI)

The Atomic Force Microscope (AFM) is a recently developed instrument that has achieved atomic resolution imaging of both conducting and non- conducting surfaces. Because the AFM is in the early stages of development, and because of the difficulty of building the instrument, it is currently in use in fewer than ten laboratories worldwide. It promises to be a valuable tool for obtaining information about engineering surfaces and aiding the .study of precision fabrication processes. This paper gives an overview of AFM technology and presents plans to build an instrument designed to look at engineering surfaces.

Day, R.D.; Russell, P.E.

1988-12-01T23:59:59.000Z

265

Iowa Powder Atomization Technologies  

SciTech Connect (OSTI)

The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

None

2012-01-01T23:59:59.000Z

266

Iowa Powder Atomization Technologies  

ScienceCinema (OSTI)

The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

None

2013-03-01T23:59:59.000Z

267

Atomic Josephson vortices  

SciTech Connect (OSTI)

We show that Josephson vortices in a quasi-one-dimensional atomic Bose Josephson junction can be controllably manipulated by imposing a difference of chemical potentials on the atomic Bose-Einstein condensate waveguides forming the junction. This effect, which has its origin in the Berry phase structure of a vortex, turns out to be very robust in the whole range of the parameters where such vortices can exist. We also propose that a Josephson vortex can be created by the phase imprinting technique and can be identified by a specific tangential feature in the interference picture produced by expanding clouds released from the waveguides.

Kaurov, V. M.; Kuklov, A. B. [Department of Engineering Science and Physics, College of Staten Island, CUNY, Staten Island, New York 10314 (United States)

2006-01-15T23:59:59.000Z

268

Atom Probe Tomography | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone byDear Friend,Arthur J. NozikAtom Probe Tomography Atom Probe

269

Atomic Collapse Observed  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone byDear Friend,Arthur J. NozikAtom Probe Tomography Atom

270

Distributed Generation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

come a long way in addressing interconnection standards for distributed generation, utilities have largely overlooked the untapped potential of these resources. Under certain...

271

LaNi.sub.5 is-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.

Bugga, Ratnakumar V. (Arcadia, CA); Fultz, Brent (Pasadena, CA); Bowman, Robert (La Mesa, CA); Surampudi, Subra Rao (Glendora, CA); Witham, Charles K. (Pasadena, CA); Hightower, Adrian (Pasadena, CA)

1999-01-01T23:59:59.000Z

272

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

SciTech Connect (OSTI)

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

273

Li{sub 4}FeH{sub 6}: Iron-containing complex hydride with high gravimetric hydrogen density  

SciTech Connect (OSTI)

Li{sub 4}FeH{sub 6}, which has the highest gravimetric hydrogen density of iron-containing complex hydrides reported so far, is synthesized by hydrogenation of a powder mixture of iron and LiH above 6.1 GPa at 900?°C. In situ synchrotron radiation X-ray diffraction measurements reveal that while kinetics require high temperature and thus high pressure for the synthesis, Li{sub 4}FeH{sub 6} is expected to be thermodynamically stable slightly below room temperature at ambient pressure; further synthetic studies to suppress the kinetic effects may enable us to synthesize Li{sub 4}FeH{sub 6} at moderate pressures. Li{sub 4}FeH{sub 6} can be recovered at ambient conditions where Li{sub 4}FeH{sub 6} is metastable.

Saitoh, Hiroyuki, E-mail: cyto@spring8.or.jp [Quantum Beam Science Center, Japan Atomic Energy Agency, Hyogo 679-5148 (Japan); Takagi, Shigeyuki; Matsuo, Motoaki; Aoki, Katsutoshi [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Iijima, Yuki [WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Endo, Naruki [Renewable Energy Research Center, National Institute of Advanced Industrial Science and Technology, Fukushima 963-0215 (Japan); Orimo, Shin-ichi [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

2014-07-01T23:59:59.000Z

274

A Ni(II) Bis(diphosphine)-Hydride Complex Containing Proton Relays - Structural Characterization and Electrocatalytic Studies  

SciTech Connect (OSTI)

The syntheses of the new 1,5-diphenyl-3,7-di(isopropyl)-1,5-diaza-3,7-diphosphacyclooctane ligand, PiPr2NPh2, is reported. The two equivalents of the ligand react with [Ni(CH3CN)6](BF4)2 to form the bis-diphosphine Ni(II)-complex [Ni(PiPr2NPh2)2](BF4)2, which acts as a proton reduction electrocatalyst. In addition to [Ni(PiPr2NPh2)2]2+, we report the syntheses and structural characterization of the Ni(0)-complex Ni(PiPr2NPh2)2, and the Ni(II)-hydride complex [HNi(PiPr2NPh2)2]BF4. The [HNi(PiPr2NPh2)2]BF4 complex represents the first Ni(II)-hydride in the [Ni(PR2NR'2)2]2+ family of compounds to be isolated and structurally characterized. In addition to the experimental data, the mechanism of electrocatalysis facilitated by [Ni(PiPr2NPh2)2]2+ is analyzed using linear free energy relationships recently established for the [Ni(PR2NR'2)2]2+ family. We thank Dr. Aaron Appel, Dr. Simone Raugei and Dr. Eric Wiedner for helpful discussions. This research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Mass spectrometry was provided at W. R. Wiley Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the Department of Energy’s office of Biological and Environmental Research located at Pacific Northwest National Laboratory. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

Das, Partha Pratim; Stolley, Ryan M.; Van Der Eide, Edwin F.; Helm, Monte L.

2014-09-30T23:59:59.000Z

275

Elements & Compounds Atoms (Elements)  

E-Print Network [OSTI]

#12;Elements & Compounds #12;Atoms (Elements) Molecules (Compounds) Cells Elements & Compounds #12 #12;First shell Second shell Third shell Hydrogen 1H Lithium 3Li Sodium 11Na Beryllium 4Be Magnesium energy Higher energy (a) A ball bouncing down a flight of stairs provides an analogy for energy levels

Frey, Terry

276

A Multi-Path Interferometer on an Atom Chip  

E-Print Network [OSTI]

Cold-atom interferometry is a powerful tool for high-precision measurements of the quantum properties of atoms, many-body interactions and gravity. Further enhancement of sensitivity and reduction of complexity of these devices are crucial conditions for success of their applications. Here we introduce a multi-path interferometric scheme that offers advances in both these aspects. It uses coherent coupling between Bose-Einstein condensates in different Zeeman states to generate an interferometric signal with sharp fringes. We realise such an interferometer as a compact easy-to-use atom-chip device and thus provide an alternative method for measurement of the light-atom and surface-atom interactions.

Jovana Petrovic; Ivan Herrera; Pietro Lombardi; Francesco S. Cataliotti

2011-11-18T23:59:59.000Z

277

A Multi-Path Interferometer on an Atom Chip  

E-Print Network [OSTI]

Cold-atom interferometry is a powerful tool for high-precision measurements of the quantum properties of atoms, many-body interactions and gravity. Further enhancement of sensitivity and reduction of complexity of these devices are crucial conditions for success of their applications. Here we introduce a multi-path interferometric scheme that offers advances in both these aspects. It uses coherent coupling between Bose-Einstein condensates in different Zeeman states to generate an interferometric signal with sharp fringes. We realise such an interferometer as a compact easy-to-use atom-chip device and thus provide an alternative method for measurement of the light-atom and surface-atom interactions.

Petrovic, Jovana; Lombardi, Pietro; Cataliotti, Francesco S

2011-01-01T23:59:59.000Z

278

Photon statistics of atomic fluorescence after {pi}-pulse excitation  

SciTech Connect (OSTI)

The photon statistics of atomic fluorescence after {pi}-pulse excitation is investigated in a system in which the input and output ports are connected to an atom. Since spontaneous decay during input pulse excitation occurs, the output pulse generally contains a multiphoton component with a certain probability. We quantitatively evaluate the probability of the output pulse containing multiple photons and determine the conditions for ideal single-photon generation.

Yoshimi, Kazuyoshi [College of Liberal Arts and Sciences, Tokyo Medical and Dental University, Ichikawa, Chiba 272-0827 (Japan); Koshino, Kazuki [College of Liberal Arts and Sciences, Tokyo Medical and Dental University, Ichikawa, Chiba 272-0827 (Japan); PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan)

2010-09-15T23:59:59.000Z

279

Thermoelectric Generators 1. Thermoelectric generator  

E-Print Network [OSTI]

. Cold Hot I - -- - - - - -- Figure 1 Electron concentration in a thermoelectric material. #12;2 A large1 Thermoelectric Generators HoSung Lee 1. Thermoelectric generator 1.1 Basic Equations In 1821 on the direction of current and material [3]. This is called the Thomson effect (or Thomson heat). These three

Lee, Ho Sung

280

New results in atomic physics at the Advanced Light Source  

SciTech Connect (OSTI)

The Advanced Light Source is the world's first low-energy third-generation synchrotron radiation source. It has been running reliably and exceeding design specifications since it began operation in October 1993. It is available to a wide community of researchers in many scientific fields, including atomic and molecular science and chemistry. Here, new results in atomic physics at the Advanced Light Source demonstrate the opportunities available in atomic and molecular physics at this synchrotron light source. The unprecedented brightness allows experiments with high flux, high spectral resolution, and nearly 100% linear polarization.

Schlachter, A.S.

1995-01-01T23:59:59.000Z

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.


281

Atom-by-atom nucleation and growth of graphene nanopores  

E-Print Network [OSTI]

Atom-by-atom nucleation and growth of graphene nanopores Christopher J. Russoa,b and J. A February 17, 2012 (received for review December 9, 2011) Graphene is an ideal thin membrane substrate structures in graphene with atomic preci- sion. It consists of inducing defect nucleation centers with ener

Golovchenko, Jene A.

282

Atomic phenomena in dense plasmas  

SciTech Connect (OSTI)

The following chapters are included: (1) the plasma environment, (2) perturbations of atomic structure, (3) perturbations of atomic collisions, (4) formation of spectral lines, and (5) dielectronic recombination. (MOW)

Weisheit, J.C.

1981-03-01T23:59:59.000Z

283

Parametric Amplification of Scattered Atom Pairs Gretchen K. Campbell, Jongchul Mun, Micah Boyd, Erik W. Streed, Wolfgang Ketterle, and David E. Pritchard*  

E-Print Network [OSTI]

and the atom- optics analog of optical parametric generation. Phase matching is essential for high efficiency parametric generation and amplification of ultracold atom pairs. A 87Rb Bose- Einstein condensate was loaded and amplification of photons and could be used to efficiently create entangled pairs of atoms. Furthermore

284

A microfabricated atomic clock  

SciTech Connect (OSTI)

Fabrication techniques usually applied to microelectromechanical systems (MEMS) are used to reduce the size and operating power of the core physics assembly of an atomic clock. With a volume of 9.5 mm{sup 3}, a fractional frequency instability of 2.5x10{sup -10} at 1 s of integration, and dissipating less than 75 mW of power, the device has the potential to bring atomically precise timing to hand-held, battery-operated devices. In addition, the design and fabrication process allows for wafer-level assembly of the structures, enabling low-cost mass-production of thousands of identical units with the same process sequence, and easy integration with other electronics.

Knappe, Svenja; Shah, Vishal; Schwindt, Peter D.D.; Hollberg, Leo; Kitching, John; Liew, Li-Anne; Moreland, John [Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States); Electromagnetics Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States)

2004-08-30T23:59:59.000Z

285

Delay in Atomic Photoionization  

SciTech Connect (OSTI)

We analyze the time delay between emission of photoelectrons from the outer valence ns and np subshells in noble gas atoms following absorption of an attosecond extreme ultraviolet pulse. Various processes such as elastic scattering of the photoelectron on the parent ion and many-electron correlation affect the apparent 'time zero' when the photoelectron leaves the atom. This qualitatively explains the time delay between photoemission from the 2s and 2p subshells of Ne as determined experimentally by attosecond streaking [Science 328, 1658 (2010)]. However, with our extensive numerical modeling, we were only able to account for less than half of the measured time delay of 21{+-}5 as. We argue that the extreme ultraviolet pulse alone cannot produce such a large time delay and it is the streaking IR field that is most likely responsible for this effect.

Kheifets, A. S. [Research School of Physical Sciences, Australian National University, Canberra ACT 0200 (Australia); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106-4030 (United States); Ivanov, I. A. [Research School of Physical Sciences, Australian National University, Canberra ACT 0200 (Australia)

2010-12-03T23:59:59.000Z

286

Appendix G: Radiation HYDROGEN ATOM  

E-Print Network [OSTI]

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix G: Radiation #12;#12;P P P E E E N NN HYDROGEN ATOM DEUTERIUM ATOM TRITIUM ATOM HYDROGEN

Pennycook, Steve

287

Appendix A: Radiation HYDROGEN ATOM  

E-Print Network [OSTI]

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix A: Radiation #12;P P P E E E N NN HYDROGEN ATOM DEUTERIUM ATOM TRITIUM ATOM HYDROGEN

Pennycook, Steve

288

VARIOUS APPLICATIONS OF ZEEMAN ATOMIC ABSORPTION SPECTROSCOPY  

E-Print Network [OSTI]

APPLICATIONS OF ZEEMAN ATOMIC ABSORPTION SPECTROSCOPYthe Zeeman effect to atomic absorption spectroscopy has beenthe Zeeman effect on atomic absorption spectrometry has been

Koizumi, Hideaki

2011-01-01T23:59:59.000Z

289

atoms: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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...

290

Atom chip apparatus for experiments with ultracold rubidium and potassium gases  

SciTech Connect (OSTI)

We present a dual chamber atom chip apparatus for generating ultracold {sup 87}Rb and {sup 39}K atomic gases. The apparatus produces quasi-pure Bose-Einstein condensates of 10{sup 4} {sup 87}Rb atoms in an atom chip trap that features a dimple and good optical access. We have also demonstrated production of ultracold {sup 39}K and subsequent loading into the chip trap. We describe the details of the dual chamber vacuum system, the cooling lasers, the magnetic trap, the multicoil magnetic transport system, the atom chip, and two optical dipole traps. Due in part to the use of light-induced atom desorption, the laser cooling chamber features a sufficiently good vacuum to also support optical dipole trap-based experiments. The apparatus is well suited for studies of atom-surface forces, quantum pumping and transport experiments, atom interferometry, novel chip-based traps, and studies of one-dimensional many-body systems.

Ivory, M. K.; Ziltz, A. R.; Fancher, C. T.; Pyle, A. J.; Sensharma, A.; Chase, B.; Field, J. P.; Garcia, A.; Aubin, S., E-mail: saaubi@wm.edu [Department of Physics, College of William and Mary, Williamsburg, Virginia 23187 (United States); Jervis, D. [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)] [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)

2014-04-15T23:59:59.000Z

291

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

SciTech Connect (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

292

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

2008-06-03T23:59:59.000Z

293

Microwave generator  

DOE Patents [OSTI]

A microwave generator is provided for generating microwaves substantially from virtual cathode oscillation. Electrons are emitted from a cathode and accelerated to an anode which is spaced apart from the cathode. The anode has an annular slit there through effective to form the virtual cathode. The anode is at least one range thickness relative to electrons reflecting from the virtual cathode. A magnet is provided to produce an optimum magnetic field having the field strength effective to form an annular beam from the emitted electrons in substantial alignment with the annular anode slit. The magnetic field, however, does permit the reflected electrons to axially diverge from the annular beam. The reflected electrons are absorbed by the anode in returning to the real cathode, such that substantially no reflexing electrons occur. The resulting microwaves are produced with a single dominant mode and are substantially monochromatic relative to conventional virtual cathode microwave generators. 6 figs.

Kwan, T.J.T.; Snell, C.M.

1987-03-31T23:59:59.000Z

294

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.

295

Atom Probe Tomography | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program Cumulus Humilis Aerosol Processing Study (CHAPS)Atom

296

The Use of Metal Hydrides for Hydrogen Recovery from Industrial Off-Gas Streams  

E-Print Network [OSTI]

to have potential for hydrogen separation technology. These were Edible Fats and Oils, Float Glass, Germanium, Heat Treating of Metal Parts, Molybdenum Powder, Powder Metallurgy, Rhenium, Silicon (Electronics) and Tungsten. While these industries... the hydrogen containing secondary streams are available, process steam is generally an important commodity and its generation during recovery of hydrogen presents a further conservation, partially off-setting the heating value reduction of the stream...

Rebello, W. J.; Guerrero, P. S.; Goodell, P. D.

297

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 Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile...

298

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

SciTech Connect (OSTI)

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

299

Light element opacities of astrophysical interest from ATOMIC  

SciTech Connect (OSTI)

We present new calculations of local-thermodynamic-equilibrium (LTE) light element opacities from the Los Alamos ATOMIC code for systems of astrophysical interest. ATOMIC is a multi-purpose code that can generate LTE or non-LTE quantities of interest at various levels of approximation. Our calculations, which include fine-structure detail, represent a systematic improvement over previous Los Alamos opacity calculations using the LEDCOP legacy code. The ATOMIC code uses ab-initio atomic structure data computed from the CATS code, which is based on Cowan's atomic structure codes, and photoionization cross section data computed from the Los Alamos ionization code GIPPER. ATOMIC also incorporates a new equation-of-state (EOS) model based on the chemical picture. ATOMIC incorporates some physics packages from LEDCOP and also includes additional physical processes, such as improved free-free cross sections and additional scattering mechanisms. Our new calculations are made for elements of astrophysical interest and for a wide range of temperatures and densities.

Colgan, J.; Kilcrease, D. P.; Magee, N. H. Jr.; Armstrong, G. S. J.; Abdallah, J. Jr.; Sherrill, M. E. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Fontes, C. J.; Zhang, H. L.; Hakel, P. [Computational Physics Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2013-07-11T23:59:59.000Z

300

Atoms.inp Archive: Crystallographic Data from GSECARS  

DOE Data Explorer [Office of Scientific and Technical Information (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

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

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

302

Transient x-ray absorption spectroscopy of hydrated halogen atom  

E-Print Network [OSTI]

Time-resolved x-ray absorption spectroscopy has been used to observe the transient species generated by one-photon detachment of an electron from aqueous bromide. The K-edge spectrum of the short-lived Br(0) atom exhibits a resonant 1s-4p transition...

Elles, Christopher G.; Shkrob, Ilya A.; Crowell, Robert A.; Arms, Dohn A.; Landahl, Eric C.

2008-02-11T23:59:59.000Z

303

Rydberg Atoms in Ponderomotive Potentials.  

E-Print Network [OSTI]

??In this thesis, we examine the ponderomotive interaction between an applied optical field and a highly excited Rydberg electron. An atom in a Rydberg state… (more)

Knuffman, Brenton J.

2009-01-01T23:59:59.000Z

304

Absorption properties of identical atoms  

SciTech Connect (OSTI)

Emission rates and other optical properties of multi-particle systems in collective and entangled states differ from those in product ones. We show the existence of similar effects in the absorption probabilities for (anti)symmetrized states of two identical atoms. The effects strongly depend on the overlapping between the atoms and differ for bosons and fermions. We propose a viable experimental verification of these ideas. -- Highlights: •The absorption rates of a pair of identical atoms in product and (anti)symmetrized states are different. •The modifications of the optical properties are essentially determined by the overlapping between the atoms. •The absorption properties differ, in some cases, for bosons and fermions.

Sancho, Pedro, E-mail: psanchos@aemet.es

2013-09-15T23:59:59.000Z

305

Low energy neutral atom imaging techniques  

SciTech Connect (OSTI)

The potential scientific return from low energy neutral atom (LENA) imaging of the magnetosphere is extraordinary. The technical challenges of LENA detection include (1) removal of LENAs from the tremendous ambient UV without losing information of their incident trajectories, (2) quantification of their trajectories, and (3) obtaining high sensitivity measurements. Two techniques that have been proposed for this purpose are based on fundamentally different atomic interaction mechanisms between LENAs and a solid: LENA transmission through an ultrathin foil and LENA reflection from a solid surface. Both of these methods provide LENA ionization (for subsequent removal from the UV by electrostatic deflection) and secondary electron emission (for start pulse generation for time-of-flight and/or coincidence). We present a comparative study of the transmission and reflection techniques based on differences in atomic interactions with solids and surfaces. We show that transmission methods yield an order of magnitude greater secondary electron emission than reflection methods. Transmission methods are shown to be sufficient for LENA energies of approximately 1 keV to greater than 30 keV. Reflection methods using low work function surfaces could be employed for LENA ionization for energies less than several keV.

Funsten, H.O. McComas, D.J.; Scime, E.E.

1993-01-01T23:59:59.000Z

306

Atomic Inference from Weak Gravitational Lensing Data  

SciTech Connect (OSTI)

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

307

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

308

Similarity between positronium-atom and electron-atom scattering  

E-Print Network [OSTI]

We employ the impulse approximation for description of positronium-atom scattering. Our analysis and calculations of Ps-Kr and Ps-Ar collisions provide theoretical explanation of the similarity between the cross sections for positronium scattering and electron scattering for a range of atomic and molecular targets observed by S. J. Brawley et al. [Science 330, 789 (2010)].

Fabrikant, I I

2015-01-01T23:59:59.000Z

309

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

310

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

311

Experimental Effects of Atomic Oxygen on the Development of an Electric Discharge Oxygen Iodine Laser  

E-Print Network [OSTI]

state I. Conventionally, a two-phase (gas-liquid) chemistry singlet oxygen generator (SOG) producesExperimental Effects of Atomic Oxygen on the Development of an Electric Discharge Oxygen Iodine of the electric discharge iodine laser continues, the role of oxygen atoms downstream of the discharge region

Carroll, David L.

312

Generation Technologies  

E-Print Network [OSTI]

Many local governments are using green power in their facilities and providing assistance to local businesses and residents to do the same. Green power is a subset of renewable energy that is produced with no GHG emissions, typically from solar, wind, geothermal, biogas, biomass, or low-impact small hydroelectric sources, includes three types of products: utility products (i.e., green power purchased from the utility through the electricity grid), renewable energy certificates (RECs), and on-site generation. Opportunities to purchase these products are increasing significantly, with annual green power market growth rates

Green Power

2005-01-01T23:59:59.000Z

313

E-Print Network 3.0 - atomization atomic absorption Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

atomic absorption Search Powered by Explorit Topic List Advanced Search Sample search results for: atomization atomic absorption Page: << < 1 2 3 4 5 > >> 1 :coherently trapped in...

314

Bogoliubov theory and bosonic atoms  

E-Print Network [OSTI]

We formulate the Bogoliubov variational principle in a mathematical framework similar to the generalized Hartree-Fock theory. Then we analyze the Bogoliubov theory for bosonic atoms in details. We discuss heuristically why the Bogoliubov energy should give the first correction to the leading energy of large bosonic atoms.

Phan Thanh Nam

2011-09-13T23:59:59.000Z

315

HYDRIDE DEVELOPMENT FOR HYDROGEN STORAGE K. J. Gross, E. Majzoub, G.J. Thomas, and G. Sandrock  

E-Print Network [OSTI]

of materials have been developed. These are; Generation III and Generation IV Ti-doped sodium alanates requirements needed to supply onboard hydrogen for PEM fuel cell powered vehicles. Two new generations as a function of temperature for both alanate phases Experimental Basics Generation II materials: Crystalline Na

316

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

2008-03-17T23:59:59.000Z

317

Turbulence in Atomic Hydrogen  

E-Print Network [OSTI]

Understanding the properties of interstellar turbulence is a great intellectual challenge and the urge to solve this problem is partially motivated by a necessity to explain the star formation mystery. This review deals with a recently suggested inversion technique as applied to atomic hydrogen. This technique allows to determine 3D turbulence statistics through the variations of 21 cm intensity. We claim that a radio interferometer is an ideal tool for such a study as its visibility function is directly related to the statistics of galactic HI. Next, we show how galactic rotation curve can be used to study the turbulence slice by slice and relate the statistics given in galactic coordinates and in the velocity space. The application of the technique to HI data reveals a shallow spectrum of the underlying HI density that is not compatible with a naive Kolmogorov picture. We show that the random density corresponding to the found spectrum tends to form low contrast filaments that are elongated towards the observer.

A. Lazarian

1998-04-02T23:59:59.000Z

318

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

319

E-Print Network 3.0 - atom traps atomic Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

for: atom traps atomic Page: << < 1 2 3 4 5 > >> 1 An output coupler for Bose condensed atoms The observations of BEC have stimulated interest in atom lasers, coherent sources of...

320

Atoms 2014, 2, 378-381; doi:10.3390/atoms2030378 OPEN ACCESS  

E-Print Network [OSTI]

Atoms 2014, 2, 378-381; doi:10.3390/atoms2030378 OPEN ACCESS atomsISSN 2218-2004 www.mdpi.com/journal/atoms.calisti@univ-amu.fr 3 International Atomic Energy Agency, Atomic and Molecular Data Unit, Nuclear Data Section, P.O. Box for the first two SLSP workshops are for simple atomic systems: the hydrogen atom or hydrogen-like one

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

Thermoelectric generator  

SciTech Connect (OSTI)

A thermoelectric generator unit is described comprising: a hot side heat exchanger including a plate having extruded retention posts projecting from one surface of the plate, and fins adapted for contact with a heating source. The fins are positioned between two of the retention posts. Retention rods are inserted between the retention posts and the base of the fins to retain the fin in thermal contact with the plate surface upon insertion of the retention rod between the engaging surface of the post and the corresponding fin. Thermoelectric semi-conductor modules are in thermal contact with the opposite side of the hot side heat exchanger plate from the contact with the fins. The modules are arranged in a grid pattern so that heat flow is directed into each of the modules from the hot side heat exchanger. The modules are connected electrically so as to combine their electrical output; and a cold side heat exchanger is in thermal contact with the modules acting as a heat sink on the opposite side of the module from the hot side heat exchanger plate so as to produce a thermal gradient across the modules.

Shakun, W.; Bearden, J.H.; Henderson, D.R.

1988-03-29T23:59:59.000Z

322

Chemical factors influencing selenium atomization  

E-Print Network [OSTI]

Atomization. (August 1980) Mary Sue Buren, B, S. , Angelo State University Chairman of Advisory Comm1ttee: Dr. Thomas M. Vickrey Selenium in an acid1c matrix was analyzed using graphite furnace atom1c absorption with Zeeman-effect background correct1on.... Nickel(II} and lanthanum( III) were introduced as matrix modifiers to determine their effect on interferences 1n selenium atom1zation. In add1tion to matr1x mod1ficat1on, surface coating the graphite furnace with z1rconium and tantalum salts was also...

Buren, Mary Sue

1980-01-01T23:59:59.000Z

323

THE INTERACTION OF RARE GAS METASTABLE ATOMS  

E-Print Network [OSTI]

in the study of metastable atom reactions. > 1 it- Fig, laa raetastable rare gas atom, three quantities are necessaryOF iiARE GAS METASTABLF ATOMS Andrew Zun-Foh Wang M a t e r

Wang, A.Z.-F.

2011-01-01T23:59:59.000Z

324

Imaging atoms in 3-D  

SciTech Connect (OSTI)

Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

Ercius, Peter

2013-10-31T23:59:59.000Z

325

Imaging atoms in 3-D  

ScienceCinema (OSTI)

Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

Ercius, Peter

2014-06-27T23:59:59.000Z

326

Absorption properties of identical atoms  

E-Print Network [OSTI]

Emission rates and other optical properties of multiparticle systems in collective and entangled states differ from those in product ones. We show the existence of similar effects in the absorption probabilities for (anti)symmetrized states of two identical atoms. The effects strongly depend on the overlapping between the atoms and differ for bosons and fermions. We propose a viable experimental verification of these ideas.

Pedro Sancho

2013-07-31T23:59:59.000Z

327

Recent Progress in ultracold atoms  

E-Print Network [OSTI]

, cold gas experiments 2. How to make a BEC out of fermions 3. Recent Progress: Controlling Interaction (Feshbach Resonance) 4. From BCS to BEC: Rotating trap and spin- polarized condensates. 5. Future research and Einstein What is Bose-Einstein condensation (BEC)? #12;300 K to 1 mK 109 atoms 1 mK to 1 mK 108 106 atoms

Baltisberger, Jay H.

328

Effect of Interatomic Separation on Entanglement Dynamics in a Two-Atom Two-Mode Model  

E-Print Network [OSTI]

We analyze the time evolution of quantum entanglement in a model consisting of two two-level atoms interacting with a two-mode electromagnetic field for a variety of initial states and interatomic separations. We study two specific atomic separations which give rise to symmetric atom-field couplings. For general atomic distances we consider a subset of initial states analytically, and then treat the more general situation numerically. We examine a variety of qualitative features such as entanglement sudden death, dynamical generation, protection, and transfer between subsystems. Our analysis shows a stark contrast in features of entanglement between the two special coupling schemes often considered; further, these features are uncharacteristic of those arising for general distances, due to the high degree of symmetry present in the special cases. The variety of behaviors in these two-mode cases suggest the importance of considering atomic separation carefully for any model where two atoms interact with a common field.

K. Sinha; N. I. Cummings; B. L. Hu

2011-11-16T23:59:59.000Z

329

Introduction Minimal generation  

E-Print Network [OSTI]

Introduction Minimal generation Random generation Minimal and probabilistic generation of finite generation of finite groups #12;Introduction Minimal generation Random generation Some motivation Let x1 random elements of G = x1, . . . , xk . (G is the group generated by x1, . . . , xk : all possible

St Andrews, University of

330

The effect of fluence and irradiation temperature on delayed hydride cracking in Zr-2.5Nb  

SciTech Connect (OSTI)

Zirconium alloys are susceptible to a stable cracking process called delayed hydride cracking (DHC). DHC has two stages: (a) crack initiation that requires a minimum crack driving force (the threshold stress intensity factor, K{sub IH}) and (b) stable crack growth that is weakly dependent on K{sub l}. The value of K{sub lH} is an important element in determining the tolerance of components to sharp flaws. The rate of cracking is used in estimating the action time for detecting propagating cracks before they become unstable. Hence, it is important for reactor operators to know how these properties change during service in reactors where the components are exposed to neutron irradiation at elevated temperatures. DHC properties were measured on a number of components, made from the two-phase alloy Zr-2.5 Nb, irradiated at temperatures in the range of 250 to 290 C in fast neutron fluxes (E {>=} 1 MeV) between 1.6 {times} 10{sup 17} and 1.8 {times} 10{sup 18} n/m{sup 2} {center_dot} s to fluences between 0.01 {times} 10{sup 25} and 9.8 {times} 10{sup 25} n/m{sup 2}. The neutron irradiation reduced K{sub IH} by about 20% and increased the velocity of cracking by a factor of about five. The increase in crack velocity was greatest with the lowest irradiation temperature. These changes in the rack velocity by neutron irradiation are explained in terms of the combined effects of irradiation hardening associated with increased -type dislocation density, and {beta}-phase decomposition. While the former process increases crack velocity, the latter process decrease it. The combined contribution is controlled by the irradiation temperature. X-ray diffraction analyses showed that the degree of {beta}-phase decomposition was highest with an irradiation temperature of 290 C while -type dislocation densities were highest with an irradiation temperature of 250 C.

Sagat, S.; Coleman, C.E.; Griffiths, M. [AECL Research, Chalk River, Ontario (Canada); Wilkins, B.J.S. [AECL Research, Pinawa, Manitoba (Canada)

1994-12-31T23:59:59.000Z

331

Topological Insulators and Metals in Atomic Optical Lattices  

E-Print Network [OSTI]

We propose the realization of topological quantum states with cold atoms trapped in an optical lattice. We discuss an experimental setup that generates a two-dimensional hexagonal lattice in the presence of a light-induced periodic vector potential, which represents a realization of the Haldane model with cold atoms. We determine theoretically the conditions necessary for observing the topological states and show that two of the key conditions are: 1) the realization of sharp boundaries and 2) the minimization of any smoothly varying component of the confining potential. We argue that, unlike their condensed matter counterparts, cold atom topological quantum states can be i) "seen", by mapping out the characteristic chiral edge states, and ii) controlled, by controlling the periodic vector potential and the properties of the confining potential.

Tudor D. Stanescu; Victor Galitski; J. Y. Vaishnav; Charles W. Clark; S. Das Sarma

2009-01-26T23:59:59.000Z

332

CO{sub 2} Mitigation Using Atomic Power  

SciTech Connect (OSTI)

Atomic power must grow 4.6%/yr in order to displace fossil fuel by 2080 and arrest CO{sub 2} at twice pre-industrial level. World energy use grows 2%/yr and World economy grows 3%/yr. Light Water Reactor (LWR) generation is expanded to the limit of the uranium supply, using a once-through fuel cycle. LWR Spent fuel plutonium is used in breeder reactor first cores. Absent atomic power, rising coal consumption will cause CO{sub 2} to double by 2050, triple by 2075, and be times 4 by 2090. Each 1.0 GWe atomic power plant delays CO{sub 2} doubling 1 week. (author)

Schenewerk, William Ernest [Parsons, Pasadena, CA, 5060 San Rafael Ave., Los Angeles CA 90042-3239 (United States)

2002-07-01T23:59:59.000Z

333

A Lattice Energy Calculation for LiH Lithium hydride is a white crystalline solid with the face-centered cubic crystal structure. The model for LiH(s)  

E-Print Network [OSTI]

operators for each of the electrons, and an electron-electron potential energy operator. HLi 1 2 r1 - 2 r1 r 2 - 1 r1 - 1 r2 - 1 r12 += When the trial wavefunction and the appropriate energy operator is usedA Lattice Energy Calculation for LiH Lithium hydride is a white crystalline solid with the face

Rioux, Frank

334

Investigations of Alternative Steam Generator Location and Flatter Core Geometry for Lead-Cooled Fast Reactors  

SciTech Connect (OSTI)

This paper concerns two independent safety investigations on critical and sub-critical heavy liquid metal cooled fast reactors using simple flow paths. The first investigation applies to locating the steam generators in the risers instead of the down-comers of a simple flow path designed sub-critical reactor of 600 MW{sub th} power. This was compared to a similar design, but with the steam generators located in the downcomers. The transients investigated were Total-Loss-of-Power and unprotected Loss-Of-Flow. It is shown that this reactor peaks at 1041 K after 29 hours during a Total-Loss-Of-Power accident. The difference between locating the steam generators in the risers and the downcomers is insignificant for this accident type. During an unprotected Loss-Of-Flow accident at full power, the core outlet temperature stabilizes at 1010 K, which is 337 K above nominal outlet temperature. The second investigation concerns a 1426 MW{sub th} critical reactor where the influence of the core height versus the core outlet temperature is studied during an unprotected Loss-Of-Flow and Total-Loss-Of-Power accident. A pancake type core geometry of 1.0 m height and 5.8 m diameter, is compared to a compact core of 2 m height and 4.5 m diameter. Moderators, like BeO and hydrides, and their influence on safety coefficients and burnup swings are also presented. Both cores incinerate transuranics from spent LWR fuel with minor actinide fraction of 5%. We show that LFRs can be designed both to breed and burn transuranics from LWRs. It is shown that the hydrides lead to the most favorable reactivity feedbacks, but the poorest reactivity swing. The computational fluid dynamics code STAR-CD was used for all thermal hydraulic calculations, and the MCNP and MCB for neutronics, and burn-up calculations. (authors)

Carlsson, Johan; Tucek, Kamil; Wider, Hartmut [Joint Research Centre, Institute for Energy, P.O. Box 2, NL-1755 ZG Petten (Netherlands)

2006-07-01T23:59:59.000Z

335

Short-range order of low-coverage Ti/Al,,111...: Implications for hydrogen storage in complex metal hydrides  

E-Print Network [OSTI]

Short-range order of low-coverage Ti/Al,,111...: Implications for hydrogen storage in complex metal-coverage Ti atoms on Al 111 as a model surface system for transition metal doped alanate hydrogen storage the dissociative chemisorption of hydrogen in Ti-doped alanate storage materials. © 2007 American Institute

Ciobanu, Cristian

336

Selfish atom selects quantum resonances at fractional atomic frequencies  

E-Print Network [OSTI]

We show that the atom as a "quantum entity", driven by an external field in the form of pulse sequence at repetition rate equal to the internal quantum frequency divided by an integer n, responds resonantly. It seeks and finds its characteristic frequencies in any possible combination of its frequencies. This is an indication of self expression by the atom at many sub-frequencies of its own transition frequencies. It is a non-intuitive phenomenon since the external repetition rate has no quantum character, yet the atom responds to it if the rate is equal to 1/n its eigen-frequency. We believe that our results will have implications in other quantum related processes, such as resonant enhancement of chemical reactions and biological processes.

Gennady A. Koganov; Reuben Shuker

2014-09-17T23:59:59.000Z

337

Waterless TiO{sub 2} atomic layer deposition using titanium tetrachloride and titanium tetraisopropoxide  

SciTech Connect (OSTI)

The surface chemistry for TiO{sub 2} atomic layer deposition (ALD) typically utilizes water or other oxidants that can oxidize underlying substrates such as magnetic disks or semiconductors. To avoid this oxidation, waterless or oxidant-free surface chemistry can be used that involves titanium halides and titanium alkoxides. In this study, waterless TiO{sub 2} ALD was accomplished using titanium tetrachloride (TiCl{sub 4}) and titanium tetraisopropoxide (TTIP). In situ transmission Fourier transform infrared (FTIR) studies were employed to study the surface species and the reactions during waterless TiO{sub 2} ALD. At low temperatures between 125 and 225??°C, the FTIR absorbance spectra revealed that the isopropoxide species remained on the surface after TTIP exposures. The TiCl{sub 4} exposures then removed the isopropoxide species and deposited additional titanium species. At high temperatures between 250 and 300??°C, the isopropoxide species were converted to hydroxyl species by ?-hydride elimination. The observation of propene gaseous reaction product by quadrupole mass spectrometry (QMS) confirmed the ?-hydride elimination reaction pathway. The TiCl{sub 4} exposures then easily reacted with the hydroxyl species. QMS studies also observed the 2-chloropropane and HCl gaseous reaction products and monitored the self-limiting nature of the TTIP reaction. Additional studies examined the waterless TiO{sub 2} ALD growth at low and high temperature. Quartz crystal microbalance measurements observed growth rates of ?3?ng/cm{sup 2} at a low temperature of 150??°C. Much higher growth rates of ?15?ng/cm{sup 2} were measured at a higher temperature of 250??°C under similar reaction conditions. X-ray reflectivity analysis measured a growth rate of 0.55 ± 0.05?Å/cycle at 250??°C. X-ray photoelectron depth-profile studies showed that the TiO{sub 2} films contained low Cl concentrations <1 at. %. This waterless TiO{sub 2} ALD process using TiCl{sub 4} and TTIP should be valuable to prevent substrate oxidation during TiO{sub 2} ALD on oxygen-sensitive substrates.

Anderson, Virginia R.; Cavanagh, Andrew S.; Abdulagatov, Aziz I. [Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215 (United States); Gibbs, Zachary M. [Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado 80309-0424 (United States); George, Steven M., E-mail: Steven.George@Colorado.Edu [Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215 and Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309-0427. (United States)

2014-01-15T23:59:59.000Z

338

RICE UNIVERSITY Ultracold Collisions in Atomic Strontium  

E-Print Network [OSTI]

RICE UNIVERSITY Ultracold Collisions in Atomic Strontium by Sarah B. Nagel A Thesis Submitted Houston, Texas February, 2008 #12;Abstract Ultracold Collisions in Atomic Strontium by Sarah B. Nagel In this work with atomic Strontium, the atoms are first laser cooled and subse- quently trapped, in a MOT

Killian, Thomas C.

339

Accelerometer using atomic waves for space applications  

E-Print Network [OSTI]

of Bose-Einstein condensation (BEC) of a dilute gas of trapped atoms in a single quantum state [18, 19, 20 of such devices in the field of navigation, surveying and analysis of earth structures. Matter-wave interferometry that the use of Bose-Einstein condensed atoms will bring the science of atom optics, and in particular atom

340

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

2014-12-12T23:59:59.000Z

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

HRTEM Imaging of Atoms at Sub-Angstrom Resolution  

SciTech Connect (OSTI)

John Cowley and his group at Arizona State University pioneered the use of transmission electron microscopy (TEM) for high-resolution imaging. Images were achieved three decades ago showing the crystal unit cell content at better than 4 Angstrom resolution. This achievement enabled researchers to pinpoint the positions of heavy atom columns within the unit cell. Lighter atoms appear as resolution is improved to sub-Angstrom levels. Currently, advanced microscopes can image the columns of the light atoms (carbon, oxygen, nitrogen) that are present in many complex structures, and even the lithium atoms present in some battery materials. Sub-Angstrom imaging, initially achieved by focal-series reconstruction of the specimen exit surface wave, will become common place for next-generation electron microscopes with CS-corrected lenses and monochromated electron beams. Resolution can be quantified in terms of peak separation and inter-peak minimum, but the limits imposed on the attainable resolution by the properties of the micro-scope specimen need to be considered. At extreme resolution the ''size'' of atoms can mean that they will not be resolved even when spaced farther apart than the resolution of the microscope.

O'Keefe, Michael A.; Allard, Lawrence F.; Blom, Douglas A.

2005-04-06T23:59:59.000Z

342

A high-flux BEC source for mobile atom interferometers  

E-Print Network [OSTI]

Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of...

Rudolph, Jan; Grzeschik, Christoph; Sternke, Tammo; Grote, Alexander; Popp, Manuel; Becker, Dennis; Müntinga, Hauke; Ahlers, Holger; Peters, Achim; Lämmerzahl, Claus; Sengstock, Klaus; Gaaloul, Naceur; Ertmer, Wolfgang; Rasel, Ernst M

2015-01-01T23:59:59.000Z

343

A high-flux BEC source for mobile atom interferometers  

E-Print Network [OSTI]

Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of demanding environments and paves the way for portable high-precision quantum sensors.

Jan Rudolph; Waldemar Herr; Christoph Grzeschik; Tammo Sternke; Alexander Grote; Manuel Popp; Dennis Becker; Hauke Müntinga; Holger Ahlers; Achim Peters; Claus Lämmerzahl; Klaus Sengstock; Naceur Gaaloul; Wolfgang Ertmer; Ernst M. Rasel

2015-01-02T23:59:59.000Z

344

Atomic Cascade in Muonic and Hadronic Hydrogen Atoms  

E-Print Network [OSTI]

The atomic cascade in $\\mu^- p$ and $\\pi^- p$ atoms has been studied with the improved version of the extended cascade model in which new quantum mechanical calculations of the differential and integral cross sections of the elastic scattering, Stark transitions and Coulomb de-excitation have been included for the principal quantum number values $n\\le 8$ and the relative energies $E \\ge 0.01$ eV. The $X$-ray yields and kinetic energy distributions are compared with the experimental data.

T. S. Jensen; V. P. Popov; V. N. Pomerantsev

2007-12-18T23:59:59.000Z

345

Observation of relativistic antihydrogen atoms  

SciTech Connect (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

346

Quantum Electrodynamics of Atomic Resonances  

E-Print Network [OSTI]

A simple model of an atom interacting with the quantized electromagnetic field is studied. The atom has a finite mass $m$, finitely many excited states and an electric dipole moment, $\\vec{d}_0 = -\\lambda_{0} \\vec{d}$, where $\\| d^{i}\\| = 1,$ $ i=1,2,3,$ and $\\lambda_0$ is proportional to the elementary electric charge. The interaction of the atom with the radiation field is described with the help of the Ritz Hamiltonian, $-\\vec{d}_0\\cdot \\vec{E}$, where $\\vec{E}$ is the electric field, cut off at large frequencies. A mathematical study of the Lamb shift, the decay channels and the life times of the excited states of the atom is presented. It is rigorously proven that these quantities are analytic functions of the momentum $\\vec{p}$ of the atom and of the coupling constant $\\lambda_0$, provided $|\\vec{p}| < mc$ and $| \\Im\\vec{p} |$ and $| \\lambda_{0} |$ are sufficiently small. The proof relies on a somewhat novel inductive construction involving a sequence of `smooth Feshbach-Schur maps' applied to a complex dilatation of the original Hamiltonian, which yields an algorithm for the calculation of resonance energies that converges super-exponentially fast.

Miguel Ballesteros; Jérémy Faupin; Jürg Fröhlich; Baptiste Schubnel

2015-03-09T23:59:59.000Z

347

Atomizing, continuous, water monitoring module  

DOE Patents [OSTI]

A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid.

Thompson, Cyril V. (Knoxville, TN); Wise, Marcus B. (Kingston, TN)

1997-01-01T23:59:59.000Z

348

Atomizing, continuous, water monitoring module  

DOE Patents [OSTI]

A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid. 3 figs.

Thompson, C.V.; Wise, M.B.

1997-07-08T23:59:59.000Z

349

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

2014-11-21T23:59:59.000Z

350

Understanding and Managing Generation Y  

E-Print Network [OSTI]

There are four generations in the workplace today; they consist of the Silent Generation, Baby Boom Generation, Generation X, and Generation Y. Generation Y, being the newest generation, is the least understood generation although marketers...

Wallace, Kevin

2007-12-14T23:59:59.000Z

351

Regeneration of aluminum hydride  

DOE Patents [OSTI]

The present invention provides methods and materials for the formation of hydrogen storage alanes, AlH.sub.x, where x is greater than 0 and less than or equal to 6 at reduced H.sub.2 pressures and temperatures. The methods rely upon reduction of the change in free energy of the reaction between aluminum and molecular H.sub.2. The change in free energy is reduced by lowering the entropy change during the reaction by providing aluminum in a state of high entropy, and by increasing the magnitude of the change in enthalpy of the reaction or combinations thereof.

Graetz, Jason Allan; Reilly, James J; Wegrzyn, James E

2012-09-18T23:59:59.000Z

352

Regeneration of aluminum hydride  

DOE Patents [OSTI]

The present invention provides methods and materials for the formation of hydrogen storage alanes, AlH.sub.x, where x is greater than 0 and less than or equal to 6 at reduced H.sub.2 pressures and temperatures. The methods rely upon reduction of the change in free energy of the reaction between aluminum and molecular H.sub.2. The change in free energy is reduced by lowering the entropy change during the reaction by providing aluminum in a state of high entropy, by increasing the magnitude of the change in enthalpy of the reaction or combinations thereof.

Graetz, Jason Allan (Mastic, NY); Reilly, James J. (Bellport, NY)

2009-04-21T23:59:59.000Z

353

PNNL Chemical Hydride Capabilities  

Broader source: Energy.gov (indexed) [DOE]

* Quantum chemistry, density functional theory, Car- Parinello, ab initio dynamics, variational transition state theory, molecular dynamics Strategy * Bring some of the...

354

Anisotropic etching of polymer films by high energy ,,100s of eV... oxygen atom neutral beams  

E-Print Network [OSTI]

Anisotropic etching of polymer films by high energy ,,Ã?100s of eV... oxygen atom neutral beams to generate an energetic 100s of eV , high flux equivalent of 10s mA/cm2 oxygen atom neutral beam. Positive of the boundary voltage which controls neutral beam energy , and was independent of substrate temperature

Economou, Demetre J.

355

Preparation of Ag Schottky contacts on n-type GaN bulk crystals grown in nitrogen rich atmosphere by the hydride vapor phase epitaxy technique  

SciTech Connect (OSTI)

Electrical properties of Schottky contacts on n-type GaN grown in nitrogen rich atmosphere with different N/Ga ratios by hydride vapor phase epitaxy were investigated. We show that tunneling of electrons from the conduction band of GaN to the metal is dominant in our samples. The quality of Schottky contacts does not only depend on surface preparation but also on the growth conditions of the crystals. Schottky contacts on these crystals show an increasing deterioration when higher N/Ga growth ratios are used. We correlate our results with the presence of negatively charged gallium vacancies in the samples. These charges compensate the positively charged donors and lead to a significant increase in series resistance.

Stübner, R., E-mail: ronald.stuebner@physik.tu-dresden.de; Kolkovsky, Vl.; Weber, J. [Technische Universität Dresden, 01062 Dresden (Germany); Leibiger, Gunnar; Habel, Frank [Freiberger Compound Materials GmbH, 09599 Freiberg (Germany)

2014-10-14T23:59:59.000Z

356

Photoabsorption by Ions and Atoms  

SciTech Connect (OSTI)

Recent progress in theoretical and experimental investigations of photoabsorption by atoms and ions is presented. Specifically, examples of near-chaotic behavior in photoionization of positive ions, low-energy manifestations of nondipole effects, high-energy breakdown of the single particle picture and new phenomenology uncovered in the inner-shell photoabsorption by negative ions are discussed.

Manson, Steven T. [Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)

2004-12-01T23:59:59.000Z

357

Entangling two atoms in spatially separated cavities through both photon emission and absorption processes  

E-Print Network [OSTI]

We consider a system consisting of a $\\Lambda$-type atom and a V-type atom, which are individually trapped in two spatially separated cavities that are connected by an optical fibre. We show that an extremely entangled state of the two atoms can be deterministically generated through both photon emission of the $\\Lambda$-type atom and photon absorption of the V-type atom in an ideal situation. The influence of various decoherence processes such as spontaneous emission and photon loss on the fidelity of the entangled state is also investigated. We find that the effect of photon leakage out of the fibre on the fidelity can be greatly diminished in some special cases. As regards the effect of spontaneous emission and photon loss from the cavities, we find that the present scheme with a fidelity higher than 0.98 may be realized under current experiment conditions.

Peng Peng; Fu-li Li

2006-12-29T23:59:59.000Z

358

Advancements in Ti Alloy Powder Production by Close-Coupled Gas Atomization  

SciTech Connect (OSTI)

As the technology for titanium metal injection molding (Ti-MIM) becomes more readily available, efficient Ti alloy fine powder production methods are required. An update on a novel close-coupled gas atomization system has been given. Unique features of the melting apparatus are shown to have measurable effects on the efficiency and ability to fully melt within the induction skull melting system (ISM). The means to initiate the melt flow were also found to be dependent on melt apparatus. Starting oxygen contents of atomization feedstock are suggested based on oxygen pick up during the atomization and MIM processes and compared to a new ASTM specification. Forming of titanium by metal injection molding (Ti-MIM) has been extensively studied with regards to binders, particle shape, and size distribution and suitable de-binding methods have been discovered. As a result, the visibility of Ti-MIM has steadily increased as reviews of technology, acceptability, and availability have been released. In addition, new ASTM specification ASTM F2885-11 for Ti-MIM for biomedical implants was released in early 2011. As the general acceptance of Ti-MIM as a viable fabrication route increases, demand for economical production of high quality Ti alloy powder for the preparation of Ti-MIM feedstock correspondingly increases. The production of spherical powders from the liquid state has required extensive pre-processing into different shapes thereby increasing costs. This has prompted examination of Ti-MIM with non-spherical particle shape. These particles are produced by the hydride/de-hydride process and are equi-axed but fragmented and angular which is less than ideal. Current prices for MIM quality titanium powder range from $40-$220/kg. While it is ideal for the MIM process to utilize spherical powders within the size range of 0.5-20 {mu}m, titanium's high affinity for oxygen to date has prohibited the use of this powder size range. In order to meet oxygen requirements the top size cut has traditionally been 45 {mu}m, and in some instances a bottom cut at +5 {mu}m is made to remove ultra-fine particles and reduce oxygen content. Predictably, use of irregular shaped or larger particle feedstock powder can reduce part quality as sintering shrinkage and part detail suffer. Thus, widespread production and technological use of Ti-MIM is limited due in large part to Ti alloy feedstock cost and availability, not MIM processing capability. Lower cost feedstock of fine, spherical Ti alloy powder with sufficient purity must be available in order to fully utilize the advantages of the Ti-MIM processing route allowing expansion of the market to small complex Ti parts in many high volume applications.

Heidloff, Andy; Rieken, Joel; Anderson, Iver; Byrd, David

2011-04-01T23:59:59.000Z

359

Realization of a superconducting atom chip  

E-Print Network [OSTI]

We have trapped rubidium atoms in the magnetic field produced by a superconducting atom chip operated at liquid Helium temperatures. Up to $8.2\\cdot 10^5$ atoms are held in a Ioffe-Pritchard trap at a distance of 440 $\\mu$m from the chip surface, with a temperature of 40 $\\mu$K. The trap lifetime reaches 115 s at low atomic densities. These results open the way to the exploration of atom--surface interactions and coherent atomic transport in a superconducting environment, whose properties are radically different from normal metals at room temperature.

Thomas Nirrengarten; Angie Qarry; Cédric Roux; Andreas Emmert; Gilles Nogues; Michel Brune; Jean-Michel Raimond; Serge Haroche

2006-10-09T23:59:59.000Z

360

Generation gaps in engineering?  

E-Print Network [OSTI]

There is much enthusiastic debate on the topic of generation gaps in the workplace today; what the generational differences are, how to address the apparent challenges, and if the generations themselves are even real. ...

Kim, David J. (David Jinwoo)

2008-01-01T23:59:59.000Z

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

CONSULTANT REPORT DISTRIBUTED GENERATION  

E-Print Network [OSTI]

CONSULTANT REPORT DISTRIBUTED GENERATION INTEGRATION COST STUDY Analytical Framework energy development, or distributed generation, in California. In May 2012, Southern California Edison Southern California Edison's approach to evaluating distributed generation impacts, and to conduct

362

A solenoidal synthetic field and the non-Abelian Aharonov-Bohm effects in neutral atoms  

E-Print Network [OSTI]

Cold neutral atoms provide a versatile and controllable platform for emulating various quantum systems. Despite efforts to develop artificial gauge fields in these systems, realizing a unique ideal-solenoid-shaped magnetic field within the quantum domain in any real-world physical system remains elusive. Here we propose a scheme to generate a "hairline" solenoid with an extremely small size around 1 micrometer which is smaller than the typical coherence length in cold atoms. Correspondingly, interference effects will play a role in transport. Despite the small size, the magnetic flux imposed on the atoms is very large thanks to the very strong field generated inside the solenoid. By arranging different sets of Laguerre-Gauss (LG) lasers, the generation of Abelian and non-Abelian SU(2) lattice gauge fields is proposed for neutral atoms in ring- and square-shaped optical lattices. As an application, interference patterns of the magnetic type-I Aharonov-Bohm (AB) effect are obtained by evolving atoms along a circle over several tens of lattice cells. During the evolution, the quantum coherence is maintained and the atoms are exposed to a large magnetic flux. The scheme requires only standard optical access, and is robust to weak particle interactions.

Ming-Xia Huo; Nie Wei; David A. W. Hutchinson; Leong Chuan Kwek

2014-08-11T23:59:59.000Z

363

Solid-State Hydriding Mechanism in the LiBH4 + MgH2 System. | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systemsBiSite CulturalDepartment2) 1/8Advanced MaterialsHalogen Atom

364

Small Generator Aggregation (Maine)  

Broader source: Energy.gov [DOE]

This section establishes requirements for electricity providers to purchase electricity from small generators, with the goal of ensuring that small electricity generators (those with a nameplate...

365

Next Generation Reactors  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nuclear Advances We are coordinating the Generation IV Nuclear Systems Initiative - an international effort to develop the next generation of nuclear power reactors. Skip...

366

Concentrated Solar Power Generation.  

E-Print Network [OSTI]

??Solar power generation is the most promising technology to transfer energy consumption reliance from fossil fuel to renewable sources. Concentrated solar power generation is a… (more)

Jin, Zhilei

2013-01-01T23:59:59.000Z

367

Role of atomic collisions in fusion  

SciTech Connect (OSTI)

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

368

Gas Diffusion in Metals: Fundamental Study of Helium-Point Defect Interactions in Iron and Kinetics of Hydrogen Desorption from Zirconium Hydride  

E-Print Network [OSTI]

spallation, fusion and Generation IV fission applications,steels: fusion, and Generation IV fission applications as058101. W.R. Corwin. U.S. Generation IV reactor integrated

Hu, Xunxiang

2013-01-01T23:59:59.000Z

369

Single Atoms on an Optical Nanofiber  

E-Print Network [OSTI]

We show that single-atoms can be trapped on the surface of a subwavelength-diameter silica-fiber, an optical nanofiber, without any external field, and that single photons spontaneously emitted from the atoms can be readily detected through the single guided-mode of the nanofiber. A key point of the work is our finding that atom trapping sites are created on the nanofiber surface by irradiating the atom cloud around the nanofiber with a violet laser radiation.

Nayak, K P

2007-01-01T23:59:59.000Z

370

Single Atoms on an Optical Nanofiber  

E-Print Network [OSTI]

We show that single-atoms can be trapped on the surface of a subwavelength-diameter silica-fiber, an optical nanofiber, without any external field, and that single photons spontaneously emitted from the atoms can be readily detected through the single guided-mode of the nanofiber. A key point of the work is our finding that atom trapping sites are created on the nanofiber surface by irradiating the atom cloud around the nanofiber with a violet laser radiation.

K. P. Nayak; K. Hakuta

2007-09-18T23:59:59.000Z

371

Atomic Ordering Enhanced Electrocatalytic Activity of Nanoalloys...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Ordering Enhanced Electrocatalytic Activity of Nanoalloys for Oxygen Reduction Reaction. Atomic Ordering Enhanced Electrocatalytic Activity of Nanoalloys for Oxygen Reduction...

372

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

373

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

374

General Atomics | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation, searchGeauga County, Ohio: Energy Resources Jump to:GenabilityAtomics Jump

375

Atoms, photons, and Information Andrew Silberfarb  

E-Print Network [OSTI]

Atoms, photons, and Information by Andrew Silberfarb B.S. California Institute of Technology, 1998 #12;Atoms, photons, and Information by Andrew Silberfarb ABSTRACT OF DISSERTATION Submitted in Partial Albuquerque, New Mexico March, 2006 #12;Atoms, photons, and Information by Andrew Silberfarb B.S. California

Deutsch, Ivan H.

376

Stark spectroscopy on rare gas atoms  

E-Print Network [OSTI]

Stark spectroscopy on rare gas atoms PROEFSCHRIFT ter verkrijging van de graad van doctor aan de-DATA LIBRARY TECHNISCHE UNIVERSITEIT EINDHOVEN Jiang, Tao Stark spectroscopy on rare gas atoms / by Tao Jiang / gasontladingen Subject headings : plasma diagnostics / Stark effect / optogalvanic spectroscopy / atomic emission

Eindhoven, Technische Universiteit

377

Sources of polarized ions and atoms  

SciTech Connect (OSTI)

In this presentation we discuss methods of producing large quantities of polarized atoms and ions (Stern-Gerlach separation, optical pumping, and spin-exchange) as well as experimental methods of measuring the degree of polarization of atomic systems. The usefulness of polarized atoms in probing the microscopic magnetic surface properties of materials will also be discussed. 39 refs., 5 figs., 2 tabs.

Cornelius, W.D.

1988-01-01T23:59:59.000Z

378

atomic mass spectrometry: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Negative *) Atomic composition Graham, Nick 3 Prospects in Analytical Atomic Spectrometry CERN Preprints Summary: Tendencies in five main branches of atomic spectrometry...

379

Self-corrected Sensors Based On Atomic Absorption Spectroscopy...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

corrected Sensors Based On Atomic Absorption Spectroscopy For Atom Flux Measurements In Molecular Beam Epitaxy. Self-corrected Sensors Based On Atomic Absorption Spectroscopy For...

380

atomic kitteni lauljatar: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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...

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

atoms barrasiye barhamkoneshhaye: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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...

382

Understanding Atom Probe Tomography of Oxide-Supported Metal...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atom Probe Tomography of Oxide-Supported Metal Nanoparticles by Correlation with Atomic Resolution Electron Understanding Atom Probe Tomography of Oxide-Supported Metal...

383

Design and Fabrication of a Chip-based Continuous-wave Atom Laser  

E-Print Network [OSTI]

We present a design for a continuous-wave (CW) atom laser on a chip and describe the process used to fabricate the device. Our design aims to integrate quadrupole magnetic guiding of ground state Rb atoms with continuous surface adsorption evaporative cooling to create a continuous Bose-Einstein condensate; out-coupled atoms from the condensate should realize a CW atom laser. We choose a geometry with three wires embedded in a spiral pattern in a silicon subtrate. The guide features an integrated solenoid to mitigate spin-flip losses and provide a tailored longitudinal magnetic field. Our design also includes multiple options for atom interferometry: accomodations are in place for laser-generated atom Fabry-Perot and Mach-Zehnder interferometers, and a pair of atomic beam X-splitters is incorporated for an all-magnetic atom Mach-Zehnder setup. We demonstrate the techniques necessary to fabricate our device using existing micro- and nano-scale fabrication equipment, and discuss future options for modified desi...

Power, E P; Vanderelzen, B; Herrera-Fierro, P; Murphy, R; Yalisove, S M; Raithel, G

2012-01-01T23:59:59.000Z

384

Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light  

E-Print Network [OSTI]

Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light and then trapped in a bottle whose "walls" are magnetic fields. Cooled atoms are ideal for exploring basic. research has traditionally been the study of the intrinsic prop erties of isolated atoms. In the early part

Johannesson, Henrik

385

Atomic flux measurement by diode-laser-based atomic absorption spectroscopy  

E-Print Network [OSTI]

Atomic flux measurement by diode-laser-based atomic absorption spectroscopy Weizhi Wang,a) R. H, California 94305 Received 5 May 1999; accepted 6 June 1999 Diode-laser-based atomic absorption AA sensors- quirements, and only the QCM measures the flux. Lamp- based atomic absorption AA sensors have been success

Fejer, Martin M.

386

NAAP Hydrogen Atom 1/9 The Hydrogen Atom Student Guide  

E-Print Network [OSTI]

Name: NAAP ­ Hydrogen Atom 1/9 The Hydrogen Atom ­ Student Guide Background Material Carefully read and the Quantum model represent the Hydrogen atom. In some cases they both describe things in the same way frequency, smaller energy, and the same velocity through space as a blue photon". #12;NAAP ­Hydrogen Atom 2

Farritor, Shane

387

Electron-hole generation and recombination rates for Coulomb scattering in graphene Farhan Rana*  

E-Print Network [OSTI]

Electron-hole generation and recombination rates for Coulomb scattering in graphene Farhan Rana ionization in zero band-gap graphene. The conduction and valence band dispersion relation in graphene.55.Cn I. INTRODUCTION Graphene is a single two-dimensional 2D atomic layer of carbon atoms forming

Afshari, Ehsan

388

Zeeman deceleration of electron-impact-excited metastable helium atoms  

E-Print Network [OSTI]

We present experimental results that demonstrate - for the first time - the Zeeman deceleration of helium atoms in the metastable 2^3S_1state. A more than 40% decrease of the kinetic energy of the beam is achieved for deceleration from 490 m/s to a final velocity of 370 m/s. Metastable atom generation is achieved with an electron-impact-excitation source whose performance is enhanced through an additional discharge-type process which we characterize in detail. Comparison of deceleration data at different electron beam pulse durations confirms that a matching between the initial particle distribution and the phase-space acceptance of the decelerator is crucial for the production of a decelerated packet with a well-defined velocity distribution. The experimental findings are in good agreement with three-dimensional numerical particle trajectory simulations.

Dulitz, Katrin; Softley, Timothy P

2015-01-01T23:59:59.000Z

389

ENERGY GENERATION RESEARCH PIER Energy Generation Research  

E-Print Network [OSTI]

ENERGY GENERATION RESEARCH PIER Energy Generation Research www.energy.ca.gov/research/ renewable/ November 2010 Sonoma County RESCO A Local Level Approach to Renewable Energy Portfolios. The Issue To address energy usage that contributes to climate change, California has enacted legislation to guide

390

Gamma ray generator  

DOE Patents [OSTI]

An embodiment of a gamma ray generator includes a neutron generator and a moderator. The moderator is coupled to the neutron generator. The moderator includes a neutron capture material. In operation, the neutron generator produces neutrons and the neutron capture material captures at least some of the neutrons to produces gamma rays. An application of the gamma ray generator is as a source of gamma rays for calibration of gamma ray detectors.

Firestone, Richard B; Reijonen, Jani

2014-05-27T23:59:59.000Z

391

Generation to Generation: The Heart of Family Medicine  

E-Print Network [OSTI]

Ageism in the Workplace. Generations Spring, 5. Westman,of caring for multiple generations simultaneously. StronglyGeneration to Generation: The Heart of Family Medicine

Winter, Robin O

2012-01-01T23:59:59.000Z

392

Fresh-Core Reload of the Neutron Radiography (NRAD) Reactor with Uranium(20)-Erbium-Zirconium-Hydride Fuel  

SciTech Connect (OSTI)

The neutron radiography (NRAD) reactor is a 250 kW TRIGA® (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The initial critical configuration developed during the fuel loading process, which contains only 56 fuel elements, has been evaluated as an acceptable benchmark experiment. The 60-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has also been evaluated as an acceptable benchmark experiment. Calculated eigenvalues differ significantly (~±1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.

John D. Bess; Thomas L. Maddock; Margaret A. Marshall; Leland M. Montierth

2013-03-01T23:59:59.000Z

393

Fresh-Core Reload of the Neutron Radiography (NRAD) Reactor with Uranium(20)-Erbium-Zirconium-Hydride Fuel  

SciTech Connect (OSTI)

The neutron radiography (NRAD) reactor is a 250 kW TRIGA® (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The 60-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has been evaluated as an acceptable benchmark experiment. The initial critical configuration developed during the fuel loading process, which contains only 56 fuel elements, has not been evaluated as it is very similar to the evaluated core configuration. The benchmark eigenvalue is 1.0012 ± 0.0029. Calculated eigenvalues differ significantly (~±1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.

John D. Bess; Thomas L. Maddock; Margaret A. Marshall; Leland M. Montierth

2011-03-01T23:59:59.000Z

394

Fresh-Core Reload of the Neutron Radiography (NRAD) Reactor with Uranium(20)-Erbium-Zirconium-Hydride Fuel  

SciTech Connect (OSTI)

The neutron radiography (NRAD) reactor is a 250 kW TRIGA® (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The 60-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has been evaluated as an acceptable benchmark experiment. The initial critical configuration developed during the fuel loading process, which contains only 56 fuel elements, has not been evaluated as it is very similar to the evaluated core configuration. The benchmark eigenvalue is 1.0012 ± 0.0029. Calculated eigenvalues differ significantly (~±1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.

John D. Bess; Thomas L. Maddock; Margaret A. Marshall; Leland M. Montierth

2014-03-01T23:59:59.000Z

395

Atomic Structure Calculations from the Los Alamos Atomic Physics Codes  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The well known Hartree-Fock method of R.D. Cowan, developed at Los Alamos National Laboratory, is used for the atomic structure calculations. Electron impact excitation cross sections are calculated using either the distorted wave approximation (DWA) or the first order many body theory (FOMBT). Electron impact ionization cross sections can be calculated using the scaled hydrogenic method developed by Sampson and co-workers, the binary encounter method or the distorted wave method. Photoionization cross sections and, where appropriate, autoionizations are also calculated. Original manuals for the atomic structure code, the collisional excitation code, and the ionization code, are available from this website. Using the specialized interface, you will be able to define the ionization stage of an element and pick the initial and final configurations. You will be led through a series of web pages ending with a display of results in the form of cross sections, collision strengths or rates coefficients. Results are available in tabular and graphic form.

Cowan, R. D.

396

Design of a dual species atom interferometer for space  

E-Print Network [OSTI]

Atom interferometers have a multitude of proposed applications in space including precise measurements of the Earth's gravitational field, in navigation & ranging, and in fundamental physics such as tests of the weak equivalence principle (WEP) and gravitational wave detection. While atom interferometers are realized routinely in ground-based laboratories, current efforts aim at the development of a space compatible design optimized with respect to dimensions, weight, power consumption, mechanical robustness and radiation hardness. In this paper, we present a design of a high-sensitivity differential dual species $^{85}$Rb/$^{87}$Rb atom interferometer for space, including physics package, laser system, electronics and software. The physics package comprises the atom source consisting of dispensers and a 2D magneto-optical trap (MOT), the science chamber with a 3D-MOT, a magnetic trap based on an atom chip and an optical dipole trap (ODT) used for Bose-Einstein condensate (BEC) creation and interferometry, the detection unit, the vacuum system for $10^{-11}$ mbar ultra-high vacuum generation, and the high-suppression factor magnetic shielding as well as the thermal control system. The laser system is based on a hybrid approach using fiber-based telecom components and high-power laser diode technology and includes all laser sources for 2D-MOT, 3D-MOT, ODT, interferometry and detection. Manipulation and switching of the laser beams is carried out on an optical bench using Zerodur bonding technology. The instrument consists of 9 units with an overall mass of 221 kg, an average power consumption of 608 W (819 W peak), and a volume of 470 liters which would well fit on a satellite to be launched with a Soyuz rocket, as system studies have shown.

Thilo Schuldt; Christian Schubert; Markus Krutzik; Lluis Gesa Bote; Naceur Gaaloul; Jonas Hartwig; Holger Ahlers; Waldemar Herr; Katerine Posso-Trujillo; Jan Rudolph; Stephan Seidel; Thijs Wendrich; Wolfgang Ertmer; Sven Herrmann; André Kubelka-Lange; Alexander Milke; Benny Rievers; Emanuele Rocco; Andrew Hinton; Kai Bongs; Markus Oswald; Matthias Franz; Matthias Hauth; Achim Peters; Ahmad Bawamia; Andreas Wicht; Baptiste Battelier; Andrea Bertoldi; Philippe Bouyer; Arnaud Landragin; Didier Massonnet; Thomas Lévèque; Andre Wenzlawski; Ortwin Hellmig; Patrick Windpassinger; Klaus Sengstock; Wolf von Klitzing; Chris Chaloner; David Summers; Philip Ireland; Ignacio Mateos; Carlos F. Sopuerta; Fiodor Sorrentino; Guglielmo M. Tino; Michael Williams; Christian Trenkel; Domenico Gerardi; Michael Chwalla; Johannes Burkhardt; Ulrich Johann; Astrid Heske; Eric Wille; Martin Gehler; Luigi Cacciapuoti; Norman Gürlebeck; Claus Braxmaier; Ernst Rasel

2014-12-08T23:59:59.000Z

397

Cylindrical neutron generator  

DOE Patents [OSTI]

A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

Leung, Ka-Ngo

2005-06-14T23:59:59.000Z

398

Cylindrical neutron generator  

DOE Patents [OSTI]

A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

Leung, Ka-Ngo (Hercules, CA)

2008-04-22T23:59:59.000Z

399

Cylindrical neutron generator  

DOE Patents [OSTI]

A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

Leung, Ka-Ngo (Hercules, CA)

2009-12-29T23:59:59.000Z

400

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

2005-04-11T23:59:59.000Z

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

Atoms can be divided into three categories: polar, non-polar and hydrogen atom  

E-Print Network [OSTI]

Since the time of Rutherford 1911) physicists and chemists commonly believed that with no electric field, the nucleus of an atom is at the centre of the electron cloud, atoms do not have permanent electric dipole moment (EDM), so that there is no polar atom in nature. In the fact, the idea is untested hypothesis. After ten years of intense research, our experiments showed that atoms can be divided into three categories: polar, non-polar and hydrogen atom. Alkali atoms are all polar atoms. The EDM of a Sodium, Potassium, Rubidium and Cesium atom in the ground state have been obtained as follows: d(Na)=1.28*10 to-8 power e.cm; d(K)=1.58*10 to-8 power e.cm; d(Rb)=1.70 *10 to-8 power e.cm; d(Cs)=1.86*10 to-8 power e.cm. All kind of atoms are non-polar atoms except for alkali and hydrogen atoms. Hydrogen atom is quite distinct from the others. The ground state in hydrogen is non-polar atom(d=0) but the excited state is polar atom, for example, the first excited state has a large EDM: d(H)=3ea=1.59*10 to-8 power e.cm (a is Bohr radius).

Pei-Lin You

2010-10-10T23:59:59.000Z

402

New wave generation  

E-Print Network [OSTI]

We present the results of a combined experimental and numerical study of the generation of internal waves using the novel internal wave generator design of Gostiaux et al. (Exp. Fluids, vol. 42, 2007, pp. 123–130). This ...

Mercier, Matthieu J.

403

An output coupler for Bose condensed atoms The observations of BEC have stimulated interest in atom lasers, coherent sources of  

E-Print Network [OSTI]

An output coupler for Bose condensed atoms The observations of BEC have stimulated interest in atom lasers, coherent sources of atomic matter waves. The build-up of atoms in the ground state of a magnetic. We demonstrated a scheme for doing this with Bose condensed atoms [1]. A variable fraction of atoms

404

Phases of Atom-Molecule Vortex Matter  

SciTech Connect (OSTI)

We study ground state vortex configurations in a rotating atom-molecule Bose-Einstein condensate. It is found that the coherent coupling between the atomic and molecular condensates can render a pairing of atomic and molecular vortices into a composite structure that resembles a carbon dioxide molecule. Structural phase transitions of vortex lattices are also explored through different physical parameters including the rotational frequency of the system.

Woo, S. J.; Bigelow, N. P. [Department of Physics and Astronomy, University of Rochester, Rochester, New York (United States); Park, Q-Han [Department of Physics, Korea University, Seoul (Korea, Republic of)

2008-03-28T23:59:59.000Z

405

Atomic-level control of the thermoelectric properties in polytypoid nanowires Sean C. Andrews,ab  

E-Print Network [OSTI]

electrical power is generated through the scavenging of waste heat. The efficiency of this conversion the scavenging of waste heat. Materials containing nanometer-sized structural and compositional features canAtomic-level control of the thermoelectric properties in polytypoid nanowires Sean C. Andrews

Yang, Peidong

406

Gas Atomization of Stainless Steel - Slow Motion  

SciTech Connect (OSTI)

Stainless steel liquid atomized by supersonic argon gas into a spray of droplets at ~1800ºC. Atomization of metal requires high pressure gas and specialized chambers for cooling and collecting the powders without contamination. The critical step for morphological control is the impingement of the gas on the melt stream. The video is a black and white high speed video of a liquid metal stream being atomized by high pressure gas. This material was atomized at the Ames Laboratory's Materials Preparation Center http://www.mpc.ameslab.gov

None

2011-01-01T23:59:59.000Z

407

Interfacing ultracold atoms and mechanical oscillators.  

E-Print Network [OSTI]

??In this thesis I present experiments investigating controlled coupling between mechanical oscillators and ultracold atoms. I report on three different coupling mechanisms. In a first… (more)

Camerer, Stephan

2011-01-01T23:59:59.000Z

408

Cold collisions of Rb and Cs atoms  

E-Print Network [OSTI]

Jamieson,M.J. Sarbazi-Azad,H. 18'th International Conference on Atomic Physics, MIT, Cambridge, MA, USA Academic Press

Jamieson, M.J.

409

Atomic Energy and Nuclear Materials Program (Tennessee)  

Broader source: Energy.gov [DOE]

The Atomic Energy and Nuclear Materials section of the Tennessee Code covers all of the regulations, licenses, permits, siting requirements, and practices relevant to a nuclear energy development. ...

410

Classical and Quantum Chaos in Atom Optics  

E-Print Network [OSTI]

The interaction of an atom with an electromagnetic field is discussed in the presence of a time periodic external modulating force. It is explained that a control on atom by electromagnetic fields helps to design the quantum analog of classical optical systems. In these atom optical systems chaos may appear at the onset of external fields. The classical and quantum chaotic dynamics is discussed, in particular in an atom optics Fermi accelerator. It is found that the quantum dynamics exhibits dynamical localization and quantum recurrences.

Farhan Saif

2006-04-10T23:59:59.000Z

411

Using Atomic Clocks to Detect Gravitational Waves  

E-Print Network [OSTI]

Atomic clocks have recently reached a fractional timing precision of $test masses separated by less than a GW wavelength, currently envisioned for the eLISA mission.

Loeb, Abraham

2015-01-01T23:59:59.000Z

412

Ps-atom scattering at low energies  

E-Print Network [OSTI]

A pseudopotential for positronium-atom interaction, based on electron-atom and positron-atom phase shifts, is constructed, and the phase shifts for Ps-Kr and Ps-Ar scattering are calculated. This approach allows us to extend the Ps-atom cross sections, obtained previously in the impulse approximation [Phys. Rev. Lett. 112, 243201 (2014)], to energies below the Ps ionization threshold. Although experimental data are not available in this low-energy region, our results describe well the tendency of the measured cross sections to drop with decreasing velocity at $venergy region, in contrast to the inter...

Fabrikant, I I

2015-01-01T23:59:59.000Z

413

Directly correlated transmission electron microscopy and atom...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Directly correlated transmission electron microscopy and atom probe tomography of grain boundary oxidation in a Ni-Al binary Directly correlated transmission electron microscopy...

414

ICPIG, July 15-20, 2007, Prague, Czech Republic C9 Heavy particle impact excitation of atomic oxygen in front of the powered  

E-Print Network [OSTI]

was assumed. Collision between O2 + and the background gas O2 generate electronically excited atomic oxygen oxygen in front of the powered electrode of oxygen rf plasmas ­ Experiment and PIC-Simulation K. Dittmann) resolved plasma induced optical emission of the atomic oxygen in an asymmetrical oxygen rf plasma (CCP

Fehske, Holger

415

CARBON ATOM DISTRIBUTION IN A DUAL PHASE STEEL: AN ATOM PROBE STUDY  

E-Print Network [OSTI]

ATOM DISTRIBUTION IN A DUAL PHASE STEEL: AN ATOM PROBE STUDY~4720 1 U.S.A. IntroductioE. Dual Phase steels are currentlymartensite-austenite dual phase steel, although the results

Barnard, S.J.

2014-01-01T23:59:59.000Z

416

Optical control of ground-state atomic orbital alignment: Cl,,2 P3/2... atoms  

E-Print Network [OSTI]

Optical control of ground-state atomic orbital alignment: Cl,,2 P3/2... atoms from HCl,,v=2,J=1-of-flight mass spectrometry. The 35 Cl 2 P3/2 atoms are aligned by two mechanisms: 1 the time-dependent transfer is conserved during the photodissociation and thus contributes to the total 35 Cl 2 P3/2 photofragment atomic

Zare, Richard N.

417

Atom chip microscopy: A novel probe for strongly correlated materials  

SciTech Connect (OSTI)

Improved measurements of strongly correlated systems will enable the predicative design of the next generation of supermaterials. In this program, we are harnessing recent advances in the quantum manipulation of ultracold atomic gases to expand our ability to probe these technologically important materials in heretofore unexplored regions of temperature, resolution, and sensitivity parameter space. We are working to demonstrate the use of atom chips to enable single-shot, large area detection of magnetic flux at the 10^-7 flux quantum level and below. By harnessing the extreme sensitivity of atomic clocks and Bose-Einstein condensates (BECs) to external perturbations, the cryogenic atom chip technology developed here will provide a magnetic flux detection capability that surpasses other techniques---such as scanning SQUIDs---by a factor of 10--1000. We are testing the utility of this technique by using rubidium BECs to image the magnetic fields emanating from charge transport and magnetic domain percolation in strongly correlated materials as they undergo temperature-tuned metal--to--insulator phase transitions. Cryogenic atom chip microscopy introduces three very important features to the toolbox of high-resolution, strongly correlated material microscopy: simultaneous detection of magnetic and electric fields (down to the sub-single electron charge level); no invasive large magnetic fields or gradients; simultaneous micro- and macroscopic spatial resolution; freedom from 1/f flicker noise at low frequencies; and, perhaps most importantly, the complete decoupling of probe and sample temperatures. The first of these features will play an important role in studying the interplay between magnetic and electric domain structure. The last two are crucial for low frequency magnetic noise detection in, e.g., the cuprate pseudogap region and for precision measurements of transport in the high temperature, technologically relevant regime inaccessible to other techniques based on superconducting scanning probes. In periods 1--3 of this grant, which we now close at the University of Illinois at Urbana-Champaign and restart at Stanford University where our new lab is being built, we have demonstrated the ability to rapidly create Rb BECs and trap them within microns of a surface ina cryostat. Period 4 of this grant, to be performed at Stanford, will demonstrate the feasibility of using atom chips with a BEC to image transport features on a cryogenically cooled surface. Successful demonstration, in future funding cycles, will lead directly to the use of system for studies of transport in exotic and technologically relevant materials such as cuprate superconductors and topological insulators.

Lev, Benjamin L

2011-11-03T23:59:59.000Z

418

Photoassociative molecular spectroscopy for atomic radiative lifetimes.  

E-Print Network [OSTI]

very far apart, in so-called long- range molecular states, their mutual interaction is ruled by plain atomic properties. The high- resolution spectroscopic study of some molecular excited states populated by photoassociation of cold atoms (photoassociative spectroscopy) gives a good illustration of this property

Boyer, Edmond

419

so Ris Report * Danish Atomic Energy Commission  

E-Print Network [OSTI]

in Bitumen of Low-Level Radioactive Waste Water Evaporator Concentrate at the Danish Atomic Energy Com Incorporation in Bitumen of Low-Level Radioactive Waste Water Evaporator Concentrate at the Danish Atomic Energy Risø Chemistry Department Abstract The plant for evaporation of radioactive waste water at the Research

420

Hartree-Fock theory for pseudorelativistic atoms  

E-Print Network [OSTI]

We study the Hartree-Fock model for pseudorelativistic atoms, that is, atoms where the kinetic energy of the electrons is given by the pseudorelativistic operator \\sqrt{(pc)^2+(mc^2)^2}-mc^2. We prove the existence of a Hartree-Fock minimizer, and prove regularity away from the nucleus and pointwise exponential decay of the corresponding orbitals.

Anna Dall'Acqua; Thomas Østergaard Sørensen; Edgardo Stockmeyer

2007-07-31T23:59:59.000Z

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.


421

Formation of $??$ atoms in $K_{?4} decay  

E-Print Network [OSTI]

We derive the decay rate of $\\pi\\mu$ atom formation in $K_{\\mu 4}$ decay. Using the obtained expressions we calculate the decay rate of atom formation and point out that considered decay can give a noticeable contribution as a background to the fundamental decay $K^+\\to \\pi^+\

S. R. Gevorkyan; A. V. Tarasov; O. O. Voskresenskaya

2009-12-01T23:59:59.000Z

422

Atomic processes in high-density plasmas  

SciTech Connect (OSTI)

This review covers dense atomic plasmas such as that produced in inertial confinement fusion. The target implosion physics along with the associated atomic physics, i.e., free electron collision phenomena, electron states I, electron states II, and nonequilibrium plasma states are described. (MOW)

More, R.M.

1982-12-21T23:59:59.000Z

423

Relativistic atomic physics at the SSC  

SciTech Connect (OSTI)

This report discusses the following proposed work for relativistic atomic physics at the Superconducting Super Collider: Beam diagnostics; atomic physics research; staffing; education; budget information; statement concerning matching funds; description and justification of major items of equipment; statement of current and pending support; and assurance of compliance.

NONE

1990-12-31T23:59:59.000Z

424

Creating a Cognitive Agent in a Virtual World: Planning, Navigation, and Natural Language Generation  

E-Print Network [OSTI]

Generation . . . . . . . . . . . . . . . . . . . . .Language Generation . . . . . . . . . . . . . . . . .Language Generation . . . . . . . . . . . . . . . . . . . .

Hewlett, William

2013-01-01T23:59:59.000Z

425

Steam generator support system  

DOE Patents [OSTI]

A support system for connection to an outer surface of a J-shaped steam generator for use with a nuclear reactor or other liquid metal cooled power source is disclosed. The J-shaped steam generator is mounted with the bent portion at the bottom. An arrangement of elongated rod members provides both horizontal and vertical support for the steam generator. The rod members are interconnected to the steam generator assembly and a support structure in a manner which provides for thermal distortion of the steam generator without the transfer of bending moments to the support structure and in a like manner substantially minimizes forces being transferred between the support structure and the steam generator as a result of seismic disturbances. 4 figs.

Moldenhauer, J.E.

1987-08-25T23:59:59.000Z

426

Steam generator support system  

DOE Patents [OSTI]

A support system for connection to an outer surface of a J-shaped steam generator for use with a nuclear reactor or other liquid metal cooled power source. The J-shaped steam generator is mounted with the bent portion at the bottom. An arrangement of elongated rod members provides both horizontal and vertical support for the steam generator. The rod members are interconnected to the steam generator assembly and a support structure in a manner which provides for thermal distortion of the steam generator without the transfer of bending moments to the support structure and in a like manner substantially minimizes forces being transferred between the support structure and the steam generator as a result of seismic disturbances.

Moldenhauer, James E. (Simi Valley, CA)

1987-01-01T23:59:59.000Z

427

Method of grid generation  

DOE Patents [OSTI]

The present invention provides a method of grid generation that uses the geometry of the problem space and the governing relations to generate a grid. The method can generate a grid with minimized discretization errors, and with minimal user interaction. The method of the present invention comprises assigning grid cell locations so that, when the governing relations are discretized using the grid, at least some of the discretization errors are substantially zero. Conventional grid generation is driven by the problem space geometry; grid generation according to the present invention is driven by problem space geometry and by governing relations. The present invention accordingly can provide two significant benefits: more efficient and accurate modeling since discretization errors are minimized, and reduced cost grid generation since less human interaction is required.

Barnette, Daniel W. (Veguita, NM)

2002-01-01T23:59:59.000Z

428

Quantum Computing with Atomic Josephson Junction Arrays  

E-Print Network [OSTI]

We present a quantum computing scheme with atomic Josephson junction arrays. The system consists of a small number of atoms with three internal states and trapped in a far-off resonant optical lattice. Raman lasers provide the "Josephson" tunneling, and the collision interaction between atoms represent the "capacitive" couplings between the modes. The qubit states are collective states of the atoms with opposite persistent currents. This system is closely analogous to the superconducting flux qubit. Single qubit quantum logic gates are performed by modulating the Raman couplings, while two-qubit gates result from a tunnel coupling between neighboring wells. Readout is achieved by tuning the Raman coupling adiabatically between the Josephson regime to the Rabi regime, followed by a detection of atoms in internal electronic states. Decoherence mechanisms are studied in detail promising a high ratio between the decoherence time and the gate operation time.

Lin Tian; P. Zoller

2003-06-12T23:59:59.000Z

429

Quantum computing with atomic Josephson junction arrays  

SciTech Connect (OSTI)

We present a quantum computing scheme with atomic Josephson junction arrays. The system consists of a small number of atoms with three internal states and trapped in a far-off-resonant optical lattice. Raman lasers provide the 'Josephson' tunneling, and the collision interaction between atoms represent the 'capacitive' couplings between the modes. The qubit states are collective states of the atoms with opposite persistent currents. This system is closely analogous to the superconducting flux qubit. Single-qubit quantum logic gates are performed by modulating the Raman couplings, while two-qubit gates result from a tunnel coupling between neighboring wells. Readout is achieved by tuning the Raman coupling adiabatically between the Josephson regime to the Rabi regime, followed by a detection of atoms in internal electronic states. Decoherence mechanisms are studied in detail promising a high ratio between the decoherence time and the gate operation time.

Tian Lin; Zoller, P. [Institute for Theoretical Physics, University of Innsbruck, A-6020 Innsbruck (Austria)

2003-10-01T23:59:59.000Z

430

Quantum-noise quenching in atomic tweezers  

SciTech Connect (OSTI)

The efficiency of extracting single atoms or molecules from an ultracold bosonic reservoir is theoretically investigated for a protocol based on lasers, coupling the hyperfine state in which the atoms form a condensate to another stable state, in which the atom experiences a tight potential in the regime of collisional blockade, the quantum tweezers. The transfer efficiency into the single-atom ground state of the tight trap is fundamentally limited by the collective modes of the condensate, which are thermally and dynamically excited. The noise due to these excitations can be quenched for sufficiently long laser pulses, thereby achieving high efficiencies. These results show that this protocol can be applied to initializing a quantum register based on tweezer traps for neutral atoms.

Zippilli, Stefano [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Theoretische Physik, Universitaet des Saarlandes, D-66041 Saarbruecken (Germany); Fachbereich Physik and Research Center OPTIMAS, Technische Universitaet Kaiserslautern, D-67663 Kaiserslautern (Germany); Mohring, Bernd; Schleich, Wolfgang [Institut fuer Quantenphysik, Universitaet Ulm, D-89081 Ulm (Germany); Lutz, Eric [Department of Physics, University of Augsburg, D-86135 Augsburg (Germany); Morigi, Giovanna [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Theoretische Physik, Universitaet des Saarlandes, D-66041 Saarbruecken (Germany)

2011-05-15T23:59:59.000Z

431

Quantum-noise quenching in atomic tweezers  

E-Print Network [OSTI]

The efficiency of extracting single atoms or molecules from an ultracold bosonic reservoir is theoretically investigated for a protocol based on lasers, coupling the hyperfine state in which the atoms form a condensate to another stable state, in which the atom experiences a tight potential in the regime of collisional blockade, the quantum tweezers. The transfer efficiency into the single-atom ground state of the tight trap is fundamentally limited by the collective modes of the condensate, which are thermally and dynamically excited. The noise due to these excitations can be quenched for sufficiently long laser pulses, thereby achieving high efficiencies. These results show that this protocol can be applied for initializing a quantum register based on tweezer traps for neutral atoms.

Stefano Zippilli; Bernd Mohring; Eric Lutz; Giovanna Morigi; Wolfgang Schleich

2011-04-15T23:59:59.000Z

432

Teleportation of an atomic momentum state  

E-Print Network [OSTI]

. The momentum state that is to be transferred is defined as uCa&5cau1p0&1cbu2p0&, ~1! FIG. 1. Schematic diagram of the quantum controlled-NOT logic gate used for the atomic momentum state teleportation. If p0 is the moment of the incoming atom along the x... of atomic center-of-mass momentum m controlled-NOT gate via atomic scattering in the PACS number~s!: 03.67.2a, 42.50.Ct, 32.80.Qk where u1p0& and u2p0& are the momentum states of the incoming atoms in 6x directions, respectively ~see Fig. 1! and ca...

Qamar, S.; Zhu, S. Y.; Zubairy, M. Suhail.

2003-01-01T23:59:59.000Z

433

Laser trapping of {sup 21}Na atoms  

SciTech Connect (OSTI)

This thesis describes an experiment in which about four thousand radioactive {sup 21}Na (t{sub l/2} = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped {sup 21}Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of {sup 21}Na {yields} {sup 21}Ne + {Beta}{sup +} + v{sub e}, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trapped atoms that we have achieved is still about two orders of magnitude lower than what is needed to conduct a measurement of the beta-asymmetry parameter at 1% of precision level, the result of this experiment proved the feasibility of trapping short-lived radioactive atoms. In this experiment, {sup 21}Na atoms were produced by bombarding {sup 24}Mg with protons of 25 MeV at the 88 in. Cyclotron of Lawrence Berkeley Laboratory. A few recently developed techniques of laser manipulation of neutral atoms were applied in this experiment. The {sup 21}Na atoms emerging from a heated oven were first transversely cooled. As a result, the on-axis atomic beam intensity was increased by a factor of 16. The atoms in the beam were then slowed down from thermal speed by applying Zeeman-tuned slowing technique, and subsequently loaded into a magneto-optical trap at the end of the slowing path. The last two chapters of this thesis present two studies on the magneto-optical trap of sodium atoms. In particular, the mechanisms of magneto-optical traps at various laser frequencies and the collisional loss mechanisms of these traps were examined.

Lu, Zheng-Tian

1994-09-01T23:59:59.000Z

434

Talkin’ Bout Wind Generation  

Broader source: Energy.gov [DOE]

The amount of electricity generated by the wind industry started to grow back around 1999, and since 2007 has been increasing at a rapid pace.

435

SNE TRAFIC GENERATOR  

Energy Science and Technology Software Center (OSTI)

003027MLTPL00 Network Traffic Generator for Low-rate Small Network Equipment Software  http://eln.lbl.gov/sne_traffic_gen.html 

436

Atomic magnetometer for human magnetoencephalograpy.  

SciTech Connect (OSTI)

We have developed a high sensitivity (<5 fTesla/{radical}Hz), fiber-optically coupled magnetometer to detect magnetic fields produced by the human brain. This is the first demonstration of a noncryogenic sensor that could replace cryogenic superconducting quantum interference device (SQUID) magnetometers in magnetoencephalography (MEG) and is an important advance in realizing cost-effective MEG. Within the sensor, a rubidium vapor is optically pumped with 795 laser light while field-induced optical rotations are measured with 780 nm laser light. Both beams share a single optical axis to maximize simplicity and compactness. In collaboration with neuroscientists at The Mind Research Network in Albuquerque, NM, the evoked responses resulting from median nerve and auditory stimulation were recorded with the atomic magnetometer and a commercial SQUID-based MEG system with signals comparing favorably. Multi-sensor operation has been demonstrated with two AMs placed on opposite sides of the head. Straightforward miniaturization would enable high-density sensor arrays for whole-head magnetoencephalography.

Schwindt, Peter; Johnson, Cort N.

2010-12-01T23:59:59.000Z

437

On the energy of electric field in hydrogen atom  

E-Print Network [OSTI]

It is shown that hydrogen atom is a unique object in physics having negative energy of electric field, which is present in the atom. This refers also to some hydrogen-type atoms: hydrogen anti-atom, atom composed of proton and antiproton, and positronium.

Yuri Kornyushin

2009-07-30T23:59:59.000Z

438

Next-generation transcriptome assembly  

E-Print Network [OSTI]

technologies - the next generation. Nat Rev Genet 11, 31-algorithms for next-generation sequencing data. Genomicsassembly from next- generation sequencing data. Genome Res

Martin, Jeffrey A.

2012-01-01T23:59:59.000Z

439

Spectral and temporal structures of high-order harmonic generation of Na in intense mid-ir laser fields  

E-Print Network [OSTI]

and efficient propagation of the wave function in space and time. Excellent agreement of the HHG spectrum into different HHG mechanisms in different energy regimes of Na atoms at long wavelengths. DOI: 10.1103/Phys,2 . The generation of har- monics in rare-gas atoms that extend up to orders of about 300 well within the water

Chu, Shih-I

440

Second generation PFB for advanced power generation  

SciTech Connect (OSTI)

Research is being conducted under a United States Department of Energy (USDOE) contract to develop a new type of coal-fueled plant for electric power generation. This new type of plant-called an advanced or second-generation pressurized fluidized bed combustion (APFBC) plant-offers the promise of 45-percent efficiency (HHV), with emissions and a cost of electricity that are significantly lower than conventional pulverized-coal-fired plants with scrubbers. This paper summarizes the pilot plant R&D work being conducted to develop this new type of plant. Although pilot plant testing is still underway, preliminary estimates indicate the commercial plant Will perform better than originally envisioned. Efficiencies greater than 46 percent are now being predicted.

Robertson, A.; Van Hook, J.

1995-11-01T23:59:59.000Z

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.


441

Laser beam generating apparatus  

DOE Patents [OSTI]

Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 11 figures.

Warner, B.E.; Duncan, D.B.

1993-12-28T23:59:59.000Z

442

Laser beam generating apparatus  

DOE Patents [OSTI]

Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus is described. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 7 figures.

Warner, B.E.; Duncan, D.B.

1994-02-15T23:59:59.000Z

443

features Utility Generator  

E-Print Network [OSTI]

#12;#12;#12;#12;features function utility Training Pool Utility Generator Per-frame function content utility classes utility classes utility Tree Decision Generator Module Utility Clustering Adaptive Content Classification Loop features content VO selection & Utility Selector content features Real

Chang, Shih-Fu

444

Event generator overview  

SciTech Connect (OSTI)

Due to their ability to provide detailed and quantitative predictions, the event generators have become an important part of studying relativistic heavy ion physics and of designing future experiments. In this talk, the author will briefly summarize recent progress in developing event generators for the relativistic heavy ion collisions.

Pang, Y.

1997-12-01T23:59:59.000Z

445

Improved solid aerosol generator  

DOE Patents [OSTI]

An improved solid aerosol generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration. The improved solid aerosol generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated aerosol in a grounded, conical heating chamber, achieving high recovery and flow rates. 2 figs.

Prescott, D.S.; Schober, R.K.; Beller, J.

1988-07-19T23:59:59.000Z

446

Internal split field generator  

DOE Patents [OSTI]

A generator includes a coil of conductive material. A stationary magnetic field source applies a stationary magnetic field to the coil. An internal magnetic field source is disposed within a cavity of the coil to apply a moving magnetic field to the coil. The stationary magnetic field interacts with the moving magnetic field to generate an electrical energy in the coil.

Thundat; Thomas George (Knoxville, TN); Van Neste, Charles W. (Kingston, TN); Vass, Arpad Alexander (Oak Ridge, TN)

2012-01-03T23:59:59.000Z

447

Precision measurement of transverse velocity distribution of a Strontium atomic beam  

E-Print Network [OSTI]

We measure precisely the transverse velocity distribution in a thermal Sr atomic beam with a velocity selective saturated fluorescence spectroscopy. By using the ultrastable laser system and narrow intercombination transition line of Sr atoms, the resolution of the velocity measured can be reached 0.13m/s, corresponding to 90$\\mu K$ in energy unit. The experimental results are agreement very well with a theoretical calculation. With the spectroscopic techniques, the absolute frequency of the intercombination transition of $^{88}$Sr is measured by an optical-frequency comb generator referenced to the SI second through an H maser, which is given by 434 829 121 318(10)kHz.

Gao, F; Xu, P; Tian, X; Wang, Y; Ren, J; Wu, Haibin; Chang, Hong

2013-01-01T23:59:59.000Z

448

Coherence Induced by Incoherent Pumping Field and Decay Process in Three-level $?$ Type Atomic System  

E-Print Network [OSTI]

Following the method of Victor V. Kozlov et al.[PhysRevA. 74. 063829],we inspect the coherence induced by incoherent pump and spontaneous decay process in $\\Lambda$ type three-level atomic system with degenerated lower duplicate levels. The system shows a coherent population trapping state and multi-steady states characteristic in different conditions. Interestingly, two kinds of steady states generated by the system in different sets of pumping and decaying parameters, the "singlet" state and the "triplet" state, exhibit stable or unstable characteristics under the action of pumping field and vacuum reservoir, which promise fruitful applications to atomic coherence and interference in quantum optics.

Bao-Quan Ou; Lin-Mei Liang; Cheng-Zu Li

2007-12-25T23:59:59.000Z

449

Engineering an atom-interferometer with modulated light-induced $3 \\pi$ spin-orbit coupling  

E-Print Network [OSTI]

We have developed an experimental method to modify the single-particle dispersion using periodic modulation of Raman beams which couple two spin-states of an ultracold atomic gas. The modulation introduces a new coupling between Raman-induced spin-orbit-coupled dressed bands, creating a second generation of dressed-state eigenlevels that feature both a novel 3{\\pi} spin-orbit coupling and a pair of avoided crossings, which is used to realize an atomic interferometer. The spin polarization and energies of these eigenlevels are characterized by studying the transport of a Bose-Einstein condensate in this system, including observing a Stueckelberg interference.

Olson, Abraham J; Blasing, David B; Niffenegger, Robert J; Chen, Yong P

2015-01-01T23:59:59.000Z

450

The dressed mobile atoms and ions  

E-Print Network [OSTI]

We consider free atoms and ions in $\\R^3$ interacting with the quantized electromagnetic field. Because of the translation invariance we consider the reduced hamiltonian associated with the total momentum. After introducing an ultraviolet cutoff we prove that the reduced hamiltonian for atoms has a ground state if the coupling constant and the total momentum are sufficiently small. In the case of ions an extra infrared regularization is needed. We also consider the case of the hydrogen atom in a constant magnetic field. Finally we determine the absolutely continuous spectrum of the reduced hamiltonian.

Laurent Amour; Benoit Grebert; Jean-Claude Guillot

2005-07-20T23:59:59.000Z

451

An Atom Trap Relying on Optical Pumping  

E-Print Network [OSTI]

We have investigated a new radiation pressure trap which relies on optical pumping and does not require any magnetic field. It employs six circularly polarized divergent beams and works on the red of a $J_{g} \\longrightarrow J_{e} = J_{g} + 1$ atomic transition with $J_{g} \\geq 1/2$. We have demonstrated this trap with cesium atoms from a vapour cell using the 852 nm $J_{g} = 4 \\longrightarrow J_{e} = 5$ resonance transition. The trap contained up to $3 \\cdot 10^{7}$ atoms in a cloud of $1/\\sqrt{e}$ radius of 330 $\\mu$m.

P. Bouyer; P. Lemonde; M. Ben Dahan; A. Michaud; C. Salomon; J. Dalibard

2005-09-21T23:59:59.000Z

452

Nanoscale atomic waveguides with suspended carbon nanotubes  

E-Print Network [OSTI]

We propose an experimentally viable setup for the realization of one-dimensional ultracold atom gases in a nanoscale magnetic waveguide formed by single doubly-clamped suspended carbon nanotubes. We show that all common decoherence and atom loss mechanisms are small guaranteeing a stable operation of the trap. Since the extremely large current densities in carbon nanotubes are spatially homogeneous, our proposed architecture allows to overcome the problem of fragmentation of the atom cloud. Adding a second nanowire allows to create a double-well potential with a moderate tunneling barrier which is desired for tunneling and interference experiments with the advantage of tunneling distances being in the nanometer regime.

V. Peano; M. Thorwart; A. Kasper; R. Egger

2005-11-23T23:59:59.000Z

453

Storing images in warm atomic vapor  

E-Print Network [OSTI]

Reversible and coherent storage of light in atomic medium is a key-stone of future quantum information applications. In this work, arbitrary two-dimensional images are slowed and stored in warm atomic vapor for up to 30 $\\mu$s, utilizing electromagnetically induced transparency. Both the intensity and the phase patterns of the optical field are maintained. The main limitation on the storage resolution and duration is found to be the diffusion of atoms. A techniqueanalogous to phase-shift lithography is employed to diminish the effect of diffusion on the visibility of the reconstructed image.

M. Shuker; O. Firstenberg; R. Pugatch; A. Ron; N. Davidson

2008-06-17T23:59:59.000Z

454

The Manhattan Project: Making the atomic bomb  

SciTech Connect (OSTI)

This article is a short history of the origins and development of the American atomic bomb program during World War II. Beginning with the scientific developments of the pre-war years, the monograph details the role of US government in conducting a secret, nationwide enterprise that took science from the laboratory and into combat with an entirely new type of weapon. The monograph concludes with a discussion of the immediate postwar period, the debate over the Atomic Energy Act of 1946, and the founding of the Atomic Energy Commission.

Gosling, F.G.

1994-09-01T23:59:59.000Z

455

Duality in spaces of finite linear combinations of atoms  

E-Print Network [OSTI]

Duality in spaces of finite linear combinations of atoms Fulvio Ricci and Joan Verdera Abstract In this note we describe the dual and the completion of the space of finite linear combinations of (p, )-atoms, )-atoms, 0

Ricci, Fulvio

456

CHARGE TRANSFER BETWEEN POSITIVE ALKALI IONS AND ATOMS  

E-Print Network [OSTI]

average velocity of atoms , ::. : . . :. . in the oven. Thisfor a potassium ", . atom beam operating under conditionsPOSITIVE ALKALI IONS AND ATOMS I W. R. Gentry, Yuan-tseh L e

Gentry, W.R.; Lee, Yuan-tseh; Mahan, Bruce H.

2008-01-01T23:59:59.000Z

457

Studying coherence in ultra-cold atomic gases  

E-Print Network [OSTI]

This thesis will discuss the study of coherence properties of ultra-cold atomic gases. The atomic systems investigated include a thermal cloud of atoms, a Bose-Einstein condensate and a fermion pair condensate. In each ...

Miller, Daniel E. (Daniel Edward)

2007-01-01T23:59:59.000Z

458

E-Print Network 3.0 - analytical atomic spectroscopy Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

A partial sampling of these techniques includes: Absorption spectroscopy Atomic absorption... spectroscopy Atomic emission spectroscopy Atomic fluorescence...

459

E-Print Network 3.0 - atomic spectroscopy technologies Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

A partial sampling of these techniques includes: Absorption spectroscopy Atomic absorption... spectroscopy Atomic emission spectroscopy Atomic fluorescence...

460

Deterministic source of a train of indistinguishable single-photon pulses with single-atom-cavity system  

E-Print Network [OSTI]

We present a mechanism to produce indistinguishable single-photon pulses on demand from an optical cavity. The sequences of two laser pulses generate, at the two Raman transitions of a four-level atom, the same cavity-mode photons without repumping of the atom between photon generations. Photons are emitted from the cavity with near-unit efficiency in well-defined temporal modes of identical shapes controlled by the laser fields. The second order correlation function reveals the single-photon nature of the proposed source. A realistic setup for the experimental implementation is presented.

A. Gogyan; S. Guérin; H. -R. Jauslin; Yu. Malakyan

2010-05-01T23:59:59.000Z

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.


461

Shaft generator transmissions  

SciTech Connect (OSTI)

Economical on-board power can be generated from two-stroke, low-speed engines by installing a multistage hollow-shaft gearbox on the propeller intermediate shaft to drive the generator. Gearbox manufacturer Asug, based in Dessau, Germany, has designed units specifically for this purpose. The Asug shaft generator drive concept for generator drives at the front end of the engine is designed to reduce installation costs and uses an integrated engine-gearbox foundation. The complete propulsion system, consisting of the diesel engine, gear with coupling and generator, can be completely or partially preassembled outside the ship`s engine room to reduce onboard assembly time. A separate foundation for this arrangement is not necessary. The company offers a full range of gearboxes to generate power from 500 kW up to 5000 kW. Gearboxes driven from the forward engine end often incorporate an additional gear stage to gain energy from an exhaust turbine. This arrangement feeds part of the exhaust energy back into the system to increase efficiency. Latest installations of Asug shaft generator gears are in container ships and cargo/container ships built in Turkey and China.

NONE

1995-11-01T23:59:59.000Z

462

Wind power generating system  

SciTech Connect (OSTI)

Normally feathered propeller blades of a wind power generating system unfeather in response to the actuation of a power cylinder that responds to actuating signals. Once operational, the propellers generate power over a large range of wind velocities. A maximum power generation design point signals a feather response of the propellers so that once the design point is reached no increase in power results, but the system still generates power. At wind speeds below this maximum point, propeller speed and power output optimize to preset values. The propellers drive a positive displacement pump that in turn drives a positive displacement motor of the swash plate type. The displacement of the motor varies depending on the load on the system, with increasing displacement resulting in increasing propeller speeds, and the converse. In the event of dangerous but not clandestine problems developing in the system, a control circuit dumps hydraulic pressure from the unfeathering cylinder resulting in a predetermined, lower operating pressure produced by the pump. In the event that a problem of potentially cladestine consequence arises, the propeller unfeathering cylinder immediately unloads. Upon startup, a bypass around the motor is blocked, applying a pressure across the motor. The motor drives the generator until the generator reaches a predetermined speed whereupon the generator is placed in circuit with a utility grid and permitted to motor up to synchronous speed.

Schachle, Ch.; Schachle, E. C.; Schachle, J. R.; Schachle, P. J.

1985-03-12T23:59:59.000Z

463

Compact neutron generator  

DOE Patents [OSTI]

A compact neutron generator has at its outer circumference a toroidal shaped plasma chamber in which a tritium (or other) plasma is generated. A RF antenna is wrapped around the plasma chamber. A plurality of tritium ion beamlets are extracted through spaced extraction apertures of a plasma electrode on the inner surface of the toroidal plasma chamber and directed inwardly toward the center of neutron generator. The beamlets pass through spaced acceleration and focusing electrodes to a neutron generating target at the center of neutron generator. The target is typically made of titanium tubing. Water is flowed through the tubing for cooling. The beam can be pulsed rapidly to achieve ultrashort neutron bursts. The target may be moved rapidly up and down so that the average power deposited on the surface of the target may be kept at a reasonable level. The neutron generator can produce fast neutrons from a T-T reaction which can be used for luggage and cargo interrogation applications. A luggage or cargo inspection system has a pulsed T-T neutron generator or source at the center, surrounded by associated gamma detectors and other components for identifying explosives or other contraband.

Leung, Ka-Ngo; Lou, Tak Pui

2005-03-22T23:59:59.000Z

464

Use of Slip Ring Induction Generator for Wind Power Generation  

E-Print Network [OSTI]

Wind energy is now firmly established as a mature technology for electricity generation. There are different types of generators that can be used for wind energy generation, among which Slip ring Induction generator proves to be more advantageous. To analyse application of Slip ring Induction generator for wind power generation, an experimental model is developed and results are studied. As power generation from natural sources is the need today and variable speed wind energy is ample in amount in India, it is necessary to study more beneficial options for wind energy generating techniques. From this need a model is developed by using Slip ring Induction generator which is a type of Asynchronous generator.

K Y Patil; D S Chavan

465

Graph Generator Survey  

SciTech Connect (OSTI)

The benchmarking effort within the Extreme Scale Systems Center at Oak Ridge National Laboratory seeks to provide High Performance Computing benchmarks and test suites of interest to the DoD sponsor. The work described in this report is a part of the effort focusing on graph generation. A previously developed benchmark, SystemBurn, allowed the emulation of dierent application behavior profiles within a single framework. To complement this effort, similar capabilities are desired for graph-centric problems. This report examines existing synthetic graph generator implementations in preparation for further study on the properties of their generated synthetic graphs.

Lothian, Josh [ORNL; Powers, Sarah S [ORNL; Sullivan, Blair D [ORNL; Baker, Matthew B [ORNL; Schrock, Jonathan [ORNL; Poole, Stephen W [ORNL

2013-12-01T23:59:59.000Z

466

Synthetic guide star generation  

DOE Patents [OSTI]

A system for assisting in observing a celestial object and providing synthetic guide star generation. A lasing system provides radiation at a frequency at or near 938 nm and radiation at a frequency at or near 1583 nm. The lasing system includes a fiber laser operating between 880 nm and 960 nm and a fiber laser operating between 1524 nm and 1650 nm. A frequency-conversion system mixes the radiation and generates light at a frequency at or near 589 nm. A system directs the light at a frequency at or near 589 nm toward the celestial object and provides synthetic guide star generation.

Payne, Stephen A. (Castro Valley, CA) [Castro Valley, CA; Page, Ralph H. (Castro Valley, CA) [Castro Valley, CA; Ebbers, Christopher A. (Livermore, CA) [Livermore, CA; Beach, Raymond J. (Livermore, CA) [Livermore, CA

2008-06-10T23:59:59.000Z

467

Interaction of an aluminum atom with a closed subshell metal atom: Spectroscopic analysis of AlZn  

E-Print Network [OSTI]

Interaction of an aluminum atom with a closed subshell metal atom: Spectroscopic analysis of Al-block main group element, aluminum, and the 3d series of transi- tion metal atoms. Although the bonding in Al

Morse, Michael D.

468

Single Supported Atoms Participate in Catalytic Processes | ornl...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Functional Materials for Energy Single Supported Atoms Participate in Catalytic Processes December 04, 2014 Pathways for NO oxidation on single Pt atoms supported on the (010)...

469

Loading rubidium atoms into a hollow core fiber .  

E-Print Network [OSTI]

??We demonstrate a procedure for cooling, trapping, and transferring rubidium atoms into a hollow core photonic band gap fiber. The atoms are first collected in… (more)

Chu, Yiwen

2007-01-01T23:59:59.000Z

470

President Roosevelt Approves Production of Atomic Bomb | National...  

National Nuclear Security Administration (NNSA)

Atomic Bomb Washington, DC President Roosevelt approves production of the atomic bomb following receipt of a National Academy of Sciences report determining that a bomb is feasible...

471

Ab Initio Atomic Simulations of Antisite Pair Recovery in Cubic...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atomic Simulations of Antisite Pair Recovery in Cubic Silicon Carbide. Ab Initio Atomic Simulations of Antisite Pair Recovery in Cubic Silicon Carbide. Abstract: The thermal...

472

Atomic-Scale Simulations of Cascade Overlap and Damage Evolution...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atomic-Scale Simulations of Cascade Overlap and Damage Evolution in Silicon Carbide. Atomic-Scale Simulations of Cascade Overlap and Damage Evolution in Silicon Carbide. Abstract:...

473

atom trap trace: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

1 An atom trap trace analysis system for measuring krypton contamination in xenon dark matter detectors Physics Websites Summary: An atom trap trace analysis system for measuring...

474

Isolation, Characterization of an Intermediate in an Oxygen Atom...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Characterization of an Intermediate in an Oxygen Atom-Transfer Reaction, and the Determination of the Bond Isolation, Characterization of an Intermediate in an Oxygen Atom-Transfer...

475

Atomic Energy Commission Explores Peaceful Uses of Nuclear Explosions...  

National Nuclear Security Administration (NNSA)

Our Jobs Working at NNSA Blog Home About Us Our History NNSA Timeline Atomic Energy Commission Explores Peaceful Uses of ... Atomic Energy Commission Explores Peaceful...

476

atomic number: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

477

atomic number density: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Quantum Physics (arXiv) Summary: We study atom-atom correlations and relative...

478

atomic number electron: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

479

atomic number range: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

480

Electronic transport in atomically thin layered materials  

E-Print Network [OSTI]

Electronic transport in atomically thin layered materials has been a burgeoning field of study since the discovery of isolated single layer graphene in 2004. Graphene, a semi-metal, has a unique gapless Dirac-like band ...

Baugher, Britton William Herbert

2014-01-01T23:59:59.000Z

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.


481

Detecting Topological Phases in Cold Atoms  

E-Print Network [OSTI]

Chern insulators are band insulators which exhibit a gap in the bulk and gapless excitations in the edge. Detection of Chern insulators is a serious challenge in cold atoms since the Hall transport measurements are technically ...

Liu, Xiong-Jun

482

Atomic effect algebras with compression bases  

SciTech Connect (OSTI)

Compression base effect algebras were recently introduced by Gudder [Demonstr. Math. 39, 43 (2006)]. They generalize sequential effect algebras [Rep. Math. Phys. 49, 87 (2002)] and compressible effect algebras [Rep. Math. Phys. 54, 93 (2004)]. The present paper focuses on atomic compression base effect algebras and the consequences of atoms being foci (so-called projections) of the compressions in the compression base. Part of our work generalizes results obtained in atomic sequential effect algebras by Tkadlec [Int. J. Theor. Phys. 47, 185 (2008)]. The notion of projection-atomicity is introduced and studied, and several conditions that force a compression base effect algebra or the set of its projections to be Boolean are found. Finally, we apply some of these results to sequential effect algebras and strengthen a previously established result concerning a sufficient condition for them to be Boolean.

Caragheorgheopol, Dan [Department of Mathematics and Informatics, Technical University of Civil Engineering in Bucharest, 124 Lacul Tei blv., RO-020396 and 'Ilie Murgulescu' Institute of Physical Chemistry, Romanian Academy, 202 Splaiul Independentei, 060021 Bucharest (Romania); Tkadlec, Josef [Department of Mathematics, Faculty of Electrical Engineering, Czech Technical University in Prague, 166 27 Prague (Czech Republic)

2011-01-15T23:59:59.000Z

483

Testing Lorentz symmetry with atoms and Light  

E-Print Network [OSTI]

This article reports on the Fifth Meeting on CPT and Lorentz Symmetry, CPT'10, held at the end of June 2010 in Bloomington, Indiana, USA. The focus is on recent tests of Lorentz symmetry using atomic and optical physics.

Neil Russell

2011-09-04T23:59:59.000Z

484

Electrical Analogs of Atomic Radiative Decay Processes  

E-Print Network [OSTI]

Simple electrical circuits are analyzed, and the results show that for high frequencies they have frequency and time responses identical to the spontaneous radiative decays of atoms. As an illustration of the analogy a ...

Fontana, Peter R.; Srivastava, Rajendra P.

1977-03-01T23:59:59.000Z

485

Quantum Structures of the Hydrogen Atom  

E-Print Network [OSTI]

Modern quantum theory introduces quantum structures (decompositions into subsystems) as a new discourse that is not fully comparable with the classical-physics counterpart. To this end, so-called Entanglement Relativity appears as a corollary of the universally valid quantum mechanics that can provide for a deeper and more elaborate description of the composite quantum systems. In this paper we employ this new concept to describe the hydrogen atom. We offer a consistent picture of the hydrogen atom as an open quantum system that naturally answers the following important questions: (a) how do the so called "quantum jumps" in atomic excitation and de-excitation occur? and (b) why does the classically and seemingly artificial "center-of-mass + relative degrees of freedom" structure appear as the primarily operable form in most of the experimental reality of atoms?

J. Jeknic-Dugic; M. Dugic; A. Francom; M. Arsenijevic

2014-05-28T23:59:59.000Z

486

Hydrogen Storage Properties of New Hydrogen-Rich BH3NH3-Metal Hydride (TiH2, ZrH2, MgH2, and/or CaH2) Composite Systems  

SciTech Connect (OSTI)

Ammonia borane (AB = NH3BH3) is one of the most attractive materials for chemical hydrogen storage due to its high hydrogen contents of 19.6 wt.%, however, impurity levels of borazine, ammonia and diborane in conjunction with foaming and exothermic hydrogen release calls for finding ways to mitigate the decomposition reactions. In this paper we present a solution by mixing AB with metal hydrides (TiH2, ZrH2, MgH2 and CaH2) which have endothermic hydrogen release in order to control the heat release and impurity levels from AB upon decomposition. The composite materials were prepared by mechanical ball milling, and their H2 release properties were characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The formation of volatile products from decomposition side reactions, such as borazine (N3B3H6) was determined by mass spectrometry (MS). Sieverts type pressure-composition-temperature (PCT) gas-solid reaction instrument was adopted to observe the kinetics of the H2 release reactions of the combined systems and neat AB. In situ 11B MAS-NMR revealed a destabilized decomposition pathway. We found that by adding specific metal hydrides to AB we can eliminate the impurities and mitigate the heat release.

Choi, Young Joon; Xu, Yimin; Shaw, Wendy J.; Ronnebro, Ewa

2012-04-19T23:59:59.000Z

487

Controlling the Ratchet Effect for Cold Atoms  

E-Print Network [OSTI]

Low-order quantum resonances manifested by directed currents have been realized with cold atoms. Here we show that by increasing the strength of an experimentally achievable delta-kicking ratchet potential, quantum resonances of a very high order may naturally emerge and can induce larger ratchet currents than low-order resonances, with the underlying classical limit being fully chaotic. The results offer a means of controlling quantum transport of cold atoms.

Anatole Kenfack; Jiangbin Gong; Arjendu K. Pattanayak

2007-11-27T23:59:59.000Z

488

Atomic resolution images of graphite in air  

SciTech Connect (OSTI)

One sample used for proof of operation for atomic resolution in STM is highly oriented pyrolytic graphite (HOPG). This sample has been imaged with many different STM`s obtaining similar results. Atomic resolution images of HOPG have now been obtained using an STM designed and built at the Precision Engineering Center. This paper discusses the theoretical predictions and experimental results obtained in imaging of HOPG.

Grigg, D.A.; Shedd, G.M.; Griffis, D.; Russell, P.E.

1988-12-01T23:59:59.000Z

489

Kinetics of atoms in a bichromatic field  

SciTech Connect (OSTI)

The kinetics of atoms in a bichromatic field is considered. Analytic solutions are obtained for the force, friction coefficient, and diffusion coefficient in the model of a two-level atom without limitations imposed on the intensity of light fields. This effect is observed in the domain of global minima and maxima of the optical potential (i.e., at points where the relative phase of two standing waves is Greek-Phi-Symbol = 0, {pi}/2.

Prudnikov, O. N., E-mail: llf@laser.nsc.ru [Novosibirsk State University (Russian Federation); Baklanov, A. S. [Russian Academy of Sciences, Institute of Laser Physics, Siberian Branch (Russian Federation)] [Russian Academy of Sciences, Institute of Laser Physics, Siberian Branch (Russian Federation); Taichenachev, A. V. [Novosibirsk State University (Russian Federation)] [Novosibirsk State University (Russian Federation); Tumaikin, A. M. [Russian Academy of Sciences, Institute of Laser Physics, Siberian Branch (Russian Federation)] [Russian Academy of Sciences, Institute of Laser Physics, Siberian Branch (Russian Federation); Yudin, V. I. [Novosibirsk State University (Russian Federation)] [Novosibirsk State University (Russian Federation)

2013-08-15T23:59:59.000Z

490

Studies of atomic hydrogen beam sources  

E-Print Network [OSTI]

Discharge tube & cavity connection to vacuum system. . 10 4 Discharge source system 12 5 Preliminary detection vacuum system 14 6 Penning trap system 16 7 Spectra taken with the bulb discharge tube on the Penning ion trap sys- tem . . 22 6 Spectra... magnetic field with cylin- drical symmetry of order 2n (n = 2, 3, 4, . . . ) results in spin and velocity dependent focussing of the atomic beam. A small permanent hexapole magnet used to focus one spin state of atomic hydrogen while defocussing...

Schafer, Todd William

1989-01-01T23:59:59.000Z

491

Hydrogen atom in rotationally invariant noncommutative space  

E-Print Network [OSTI]

We consider the noncommutative algebra which is rotationally invariant. The hydrogen atom is studied in a rotationally invariant noncommutative space. We find the corrections to the energy levels of the hydrogen atom up to the second order in the parameter of noncommutativity. The upper bound of the parameter of noncommutativity is estimated on the basis of the experimental results for 1s-2s transition frequency.

Kh. P. Gnatenko; V. M. Tkachuk

2014-11-03T23:59:59.000Z

492

Excess optical quantum noise in atomic sensors  

E-Print Network [OSTI]

Enhanced nonlinear optical response of a coherent atomic medium is the basis for many atomic sensors, and their performance is ultimately limited by the quantum fluctuations of the optical read-out. Here we demonstrate that off-resonant interactions can significantly modify the quantum noise of the optical field, even when their effect on the mean signal is negligible. We illustrate this concept by using an atomic magnetometer based on the nonlinear Faraday effect: the rotation of the light polarization is mainly determined by the resonant light-induced spin alignment, which alone does not change the photon statistics of the optical probe. Yet, we found that the minimum noise of output polarization rotation measurements is above the expected shot noise limit. This excess quantum noise is due to off-resonant coupling and grows with atomic density. We also show that the detection scheme can be modified to reduce the measured quantum noise (even below the shot-noise limit) but only at the expense of the reduced rotational sensitivity. These results show the existence of previously unnoticed factors in fundamental limitations in atomic magnetometry and could have impacts in many other atom-light based precision measurements.

Irina Novikova; Eugeniy E. Mikhailov; Yanhong Xiao

2014-10-14T23:59:59.000Z

493

Cavity cooling of an atomic array  

E-Print Network [OSTI]

While cavity cooling of a single trapped emitter was demonstrated, cooling of many particles in an array of harmonic traps needs investigation and poses a question of scalability. This work investigates the cooling of a one dimensional atomic array to the ground state of motion via the interaction with the single mode field of a high-finesse cavity. The key factor ensuring the cooling is found to be the mechanical inhomogeneity of the traps. Furthermore it is shown that the pumped cavity mode does not only mediate the cooling but also provides the necessary inhomogeneity if its periodicity differs from the one of the array. This configuration results in the ground state cooling of several tens of atoms within a few milliseconds, a timescale compatible with current experimental conditions. Moreover, the cooling rate scaling with the atom number reveals a drastic change of the dynamics with the size of the array: atoms are either cooled independently, or via collective modes. In the latter case the cavity mediated atom interaction destructively slows down the cooling as well as increases the mean occupation number, quadratically with the atom number. Finally, an order of magnitude speed up of the cooling is predicted as an outcome the optimization scheme based on the adjustment of the array versus the cavity mode periodicity.

Oxana Mishina

2014-04-16T23:59:59.000Z

494

From Lattice Gauge Theories to Hydrogen Atoms  

E-Print Network [OSTI]

Using canonical transformations we obtain a complete and most economical realization of the loop or physical Hilbert space of pure $SU(2)_{2+1}$ lattice gauge theory in terms of Wigner coupled Hilbert spaces of hydrogen atoms. One hydrogen atom is assigned to every plaquette of the lattice. The SU(2) gauge theory loop basis states over a plaquette are the bound energy eigenstates $|n l m>$ of the corresponding hydrogen atom. The Wigner couplings of these hydrogen atom energy eigenstates on different plaquettes provide a complete SU(2) gauge theory loop basis on the entire lattice. The loop basis is invariant under simultaneous rotations of all hydrogen atoms. The dual description of this basis diagonalizes all Wilson loop operators and is given in terms of hyperspherical harmonics on the SU(2) group manifold $S^3$. The SU(2) loop dynamics is governed by a "SU(2) spin Hamiltonian" without any gauge fields. The relevance of the hydrogen atom basis and its dynamical symmetry group SO(4,2) in SU(2) loop dynamics in weak coupling continuum limit ($g^2\\rightarrow 0$) is emphasized.

Manu Mathur; T. P. Sreeraj

2014-10-13T23:59:59.000Z

495

Generating electricity from viruses  

SciTech Connect (OSTI)

Berkeley Lab's Seung-Wuk Lee discusses "Generating electricity from viruses" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas.

Lee, Seung-Wuk

2013-10-31T23:59:59.000Z

496

Energy and Mass Generation  

E-Print Network [OSTI]

Modifications in the energy momentum dispersion laws due to a noncommutative geometry, have been considered in recent years. We examine the oscillations of extended objects in this perspective and find that there is now a "generation" of energy.

Burra G. Sidharth

2010-03-11T23:59:59.000Z

497

Contextualizing generative design  

E-Print Network [OSTI]

Generative systems have been widely used to produce two- and three-dimensional constructs, in an attempt to escape from our preconceptions and pre-existing spatial language. The challenge is to use this mechanism in ...

Arida, Saeed, 1977-

2004-01-01T23:59:59.000Z

498

Monte Carlo event generators  

SciTech Connect (OSTI)

I review recent progress in the physics of parton shower Monte Carlos, emphasizing the ideas which allow the inclusion of higher-order matrix elements into the framework of event generators.

Frixione, Stefano [INFN, Sezione di Genova, Via Dodecaneso 33, 16146 Genova (Italy)

2005-10-06T23:59:59.000Z

499

Generating electricity from viruses  

ScienceCinema (OSTI)

Berkeley Lab's Seung-Wuk Lee discusses "Generating electricity from viruses" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas.

Lee, Seung-Wuk

2014-06-23T23:59:59.000Z

500

Oscillating fluid power generator  

SciTech Connect (OSTI)

A system and method for harvesting the kinetic energy of a fluid flow for power generation with a vertically oriented, aerodynamic wing structure comprising one or more airfoil elements pivotably attached to a mast. When activated by the moving fluid stream, the wing structure oscillates back and forth, generating lift first in one direction then in the opposite direction. This oscillating movement is converted to unidirectional rotational movement in order to provide motive power to an electricity generator. Unlike other oscillating devices, this device is designed to harvest the maximum aerodynamic lift forces available for a given oscillation cycle. Because the system is not subjected to the same intense forces and stresses as turbine systems, it can be constructed less expensively, reducing the cost of electricity generation. The system can be grouped in more compact clusters, be less evident in the landscape, and present reduced risk to avian species.

Morris, David C

2014-02-25T23:59:59.000Z