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Note: This page contains sample records for the topic "hydride vapor phase" from the National Library of EnergyBeta (NLEBeta).
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1

A new phase in palladium hydride technology  

DOE Green Energy (OSTI)

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

Walters, R.T.

1991-12-31T23:59:59.000Z

2

A new phase in palladium hydride technology  

DOE Green Energy (OSTI)

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

Walters, R.T.

1991-01-01T23:59:59.000Z

3

Phase Field Modeling of Coherent Zirconium Hydrides ...  

Science Conference Proceedings (OSTI)

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

4

Vapor phase modifiers for oxidative coupling  

DOE Patents (OSTI)

Volatilized metal compounds retard vapor phase alkane conversion reactions in oxidative coupling processes that convert lower alkanes to higher hydrocarbons.

Warren, Barbara K. (Charleston, WV)

1991-01-01T23:59:59.000Z

5

Vapor phase heat transport systems  

DOE Green Energy (OSTI)

Vapor phase heat-transport systems are being tested in two of the passive test cells at Los Alamos. The systems consist of an active fin-and-tube solar collector and a condenser inside a water storage tank. The refrigerant, R-11, can be returned to the collector by a pump or by a self-pumping scheme. In one of the test cells the liquid was self-pumped to the roof-mounted collector 17 ft above the condenser. A mechanical valve was designed and tested that showed that the system could operate in a completely passive mode. Performance comparisons have been made with a passive water wall test cell.

Hedstrom, J.C.

1984-01-01T23:59:59.000Z

6

Vapor phase modifiers for oxidative coupling  

DOE Patents (OSTI)

Volatilized metal compounds are described which are capable of retarding vapor phase alkane conversion reactions in oxidative coupling processes that convert lower alkanes to higher hydrocarbons.

Warren, B.K.

1991-12-17T23:59:59.000Z

7

Liquid-phase compositions from vapor-phase analyses  

SciTech Connect

Arsenic normally is not considered to be a contaminant. However, because arsenic was found in many cylinders of UF{sub 6}, including in corrosion products, a study was performed of the distribution of the two arsenic fluorides, AsF{sub 3} and AsF{sub 5}, between liquid and vapor phases. The results of the study pertain to condensation or vaporization of liquid UF{sub 6}. This study includes use of various experimental data plus many extrapolations necessitated by the meagerness of the experimental data. The results of this study provide additional support for the vapor-liquid equilibrium model of J.M. Prausnitz and his coworkers as a means of describing the distribution of various impurities between vapor and liquid phases of UF{sub 6}. Thus, it is concluded that AsF{sub 3} will tend to concentrate in the liquid phase but that the concentration of AsF{sub 5} in the vapor phase will exceed its liquid-phase concentration by a factor of about 7.5, which is in agreement with experimental data. Because the weight of the liquid phase in a condensation operation may be in the range of thousands of times that of the vapor phase, most of any AsF{sub 5} will be in the liquid phase in spite of this separation factor of 7.5. It may also be concluded that any arsenic fluorides fed into a uranium isotope separation plant will either travel with other low-molecular-weight gases or react with materials present in the plant. 25 refs., 3 figs., 6 tabs.

Davis, W. Jr. (Oak Ridge Gaseous Diffusion Plant, TN (USA)); Cochran, H.D. (Oak Ridge National Lab., TN (USA))

1990-02-01T23:59:59.000Z

8

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

E-Print Network (OSTI)

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

Kuhr, Samuel Houston

2012-08-01T23:59:59.000Z

9

Preliminary assessment of halogenated alkanes as vapor-phase tracers  

DOE Green Energy (OSTI)

New tracers are needed to evaluate the efficiency of injection strategies in vapor-dominated environments. One group of compounds that seems to meet the requirements for vapor-phase tracing are the halogenated alkanes (HCFCs). HCFCs are generally nontoxic, and extrapolation of tabulated thermodynamic data indicate that they will be thermally stable and nonreactive in a geothermal environment. The solubilities and stabilities of these compounds, which form several homologous series, vary according to the substituent ratios of fluorine, chlorine, and hydrogen. Laboratory and field tests that will further define the suitability of HCFCs as vapor-phase tracers are under way.

Adams, Michael C.; Moore, Joseph N.; Hirtz, Paul

1991-01-01T23:59:59.000Z

10

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

DOE Green Energy (OSTI)

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

Argabright, T.A.

1982-02-01T23:59:59.000Z

11

Hydrogen Outgassing from Lithium Hydride  

DOE Green Energy (OSTI)

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

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

2006-04-20T23:59:59.000Z

12

Separation of heavy water by vapor-phase thermal diffusion coupled with distillation and condensation  

Science Conference Proceedings (OSTI)

A study on the enrichment of heavy water in a vapor-phase thermal-diffusion column has been conducted. With the combination of the effects of distillation, vapor-phase thermal diffusion, and partial condensation, considerable improvement in the degree of enrichment has been achieved in a vapor-phase column rather than in a liquid-phase column. It was also found that even the part of enrichment contributed only by vapor-phase thermal-diffusion effect is much higher than that obtained by liquid-phase thermal diffusion.

Yeh, H.M. [Tamkang Univ., Taiwan (China); Chang, S.M. [Cheng Kung Univ., Taiwan (China)

1994-08-01T23:59:59.000Z

13

Vaporization behavior of non-stoichiometric refractory carbide materials and direct observations of the vapor phase using laser diagnostics  

DOE Green Energy (OSTI)

Transition metal and actinide carbides, such as ZrC or NbC and UC or ThC, exhibit a wide range of stoichiometry, and therefore vaporize incongruently. At long times, steady state vaporization can be achieved where relative concentrations of atomic species on solid surface equals that in the gas phase. The surface composition under these steady state conditions is termed the congruently vaporizing composition, (CVC). Modeling the vaporization or corrosion behavior of this dynamic process is complex and requires an understanding of how the surface composition changes with time and a knowledge of CVC, which is both temperature and atmosphere dependent. This paper describes vaporization and corrosion behavior of non-stoichiometric refractory carbide materials and, as an example, describes a thermokinetic model that characterizes the vaporization behavior of the complex carbide U{sub x}Zr{sub 1-x}C{sub y} in hydrogen at 2500 to 3200 K. This model demonstrates that steady state corrosion of U{sub x}Zr{sub l-x}C{sub y} is rate limited by gaseous transport of Zr where partial pressure of Zr is determined by CVC. This paper also briefly describes efforts to image and characterize the vapor phase above the surface of ZrC in static and flowing gas environments using planar laser induced fluorescence. We have developed the method for monitoring and controlling the corrosion behavior of nuclear fuels in nuclear thermal rockets. However, the techniques described can be used, to image boundary layers, and could be used verifying corrosion models.

Butt, D.P.; Wantuck, P.J.; Rehse, S.J.; Wallace, T.C. Sr.

1993-09-01T23:59:59.000Z

14

AlGaAsSb/GaSb Distributed Bragg Reflectors Grown by Organometallic Vapor Phase Epitaxy  

SciTech Connect

The first AlGaAsSb/GaSb quarter-wave distributed Bragg reflectors grown by metallic vapor phase epitaxy are reported. The peak reflectance is 96% for a 10-period structure.

C.A. Wang; C.J. Vineis; D.R. Calawa

2002-02-13T23:59:59.000Z

15

Hydride compositions  

DOE Patents (OSTI)

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

Lee, Myung W. (North Augusta, SC)

1995-01-01T23:59:59.000Z

16

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

17

Microwave-assisted fast vapor-phase transport synthesis of MnAPO-5 molecular sieves  

Science Conference Proceedings (OSTI)

MnAPO-5 was prepared by a microwave-assisted vapor-phase transport method at 180 deg. C in short times. The products were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectra, UV-vis spectroscopic measurement, NH{sub 3}-temperature-programmed desorption and esterification reaction. It was found that dry gels prepared with aluminum isopropoxide, phosphoric acid and manganese acetate could be transferred to MnAPO-5 in the vapors of triethylamine and water by the microwave-assisted vapor-phase transport method at 180 deg. C for less than 30 min. The crystallization time was greatly reduced by the microwave heating compared with the conventional heating. The resulting MnAPO-5 exhibited much smaller particle sizes, higher surface areas and slightly higher catalytic activity in the esterification of acetic acid and butyl alcohol than those prepared by the conventional vapor-phase transport method and hydrothermal synthesis.

Shao Hui [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China); Department of Chemical Engineering, Jiangsu Polytechnic University, Changzhou 213016 (China); Yao Jianfeng; Ke Xuebin [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China); Zhang Lixiong [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China)], E-mail: lixiongzhang@yahoo.com; Xu Nanping [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China)

2009-04-02T23:59:59.000Z

18

Liquid-phase dispersion during injection into vapor-dominated reservoirs  

DOE Green Energy (OSTI)

The behavior of water injection plumes in vapor-dominated reservoirs is examined. Stressing the similarity to water infiltration in heterogeneous soils, we suggest that ever-present heterogeneities in individual fractures and fracture networks will cause a lateral broadening of descending injection plumes. The process of lateral spreading of liquid phase is viewed in analogy to transverse dispersion in miscible displacement. To account for the postulated ``phase dispersion`` the conventional two-phase immiscible flow theory is extended by adding a Fickian-type dispersive term. The validity of the proposed phase dispersion model is explored by means of simulations with detailed resolution of small-scale heterogeneity. We also present an illustrative application to injection into a depleted vapor zone. It is concluded that phase dispersion effects will broaden descending injection plumes, with important consequences for pressure support and potential water breakthrough at neighboring production wells.

Pruess, K.

1994-01-01T23:59:59.000Z

19

Condensed phase conversion and growth of nanorods and other materials instead of from vapor  

DOE Patents (OSTI)

Compositions, systems and methods are described for condensed phase conversion and growth of nanorods and other materials. A method includes providing a condensed phase matrix material; and activating the condensed phase matrix material to produce a plurality of nanorods by condensed phase conversion and growth from the condensed phase matrix material instead of from vapor. The compositions are very strong. The compositions and methods provide advantages because they allow (1) formation rates of nanostructures necessary for reasonable production rates, and (2) the near net shaped production of component structures.

Geohegan, David B. (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Puretzky, Alex A. (Knoxville, TN); Fan, Xudong (Oak Ridge, TN)

2010-10-19T23:59:59.000Z

20

Published on Web 08/16/2003 Vapor Phase Synthesis of Tungsten Nanowires  

E-Print Network (OSTI)

Vapor phase methods for synthesizing metal nanowires directly without the help of templates have not been studied extensively. Even though there have been few reports with one dating back to 1877 on metal whisker synthesis from the vapor phase, the inconclusive growth mechanism did not lead to any serious developments for nanowires. 1 Recently, there are also two reports with one using hydrogen on tungsten oxide for tungsten nanowires, and another using decomposition of tungsten complexed organic precursors for amorphous carbon sheathed, polycrystalline tungsten nanowires. 2 In this context, we report a novel method in which nucleation and growth of metal oxides at temperatures higher than the oxide decomposition temperatures lead to the respective metal nanowires. Specifically, we demonstrate this concept with the bulk synthesis of tungsten nanowires. The chemical vapor transport of tungsten in the presence of oxygen onto substrates kept at temperatures

Sreeram Vaddiraju; Hari Ch; Mahendra K. Sunkara

2003-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

Cubic GaN Light Emitting Diode Grown by Metalorganic Vapor-Phase Epitaxy  

E-Print Network (OSTI)

this paper, we report on the doping characteristics of Si and Mg in the growth of cubic GaN by metalorganic vapor-phase epitaxy (MOVPE). We also report the growth of a p-n diode structure made of cubic GaN, and its characterization by electron-beam-induced-current (EBIC) and current injection measurements.

Hidenao Tanaka Member; Vapor-phase Epitaxy; Atsushi Nakadaira

2000-01-01T23:59:59.000Z

22

Microsoft Word - Vapor Phase Elemental Sulfur Tech Brief DRAFT bbl 08-24.docx  

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

AT A GLANCE AT A GLANCE  eliminates excavation expense  applicable to large or small sites  straightforward deployment  uses heat to distribute sulfur throughout a soil  mercury reacts with sulfur to form immobile and insoluble minerals  patent applied for TechBrief Vapor Phase Elemental Sulfur Amendment for Sequestering Mercury in Contaminated Soil Scientists at the Savannah River National Laboratory (SRNL) have identified a method of targeting mercury in contaminated soil zone by use of sulfur vapor heated gas. Background Mercury contamination in soil is a common problem in the environment. The most common treatment is excavation - a method that works well for small sites where the

23

Liquid-phase and vapor-phase dehydration of organic/water solutions  

DOE Patents (OSTI)

Processes for dehydrating an organic/water solution by pervaporation or vapor separation using fluorinated membranes. The processes are particularly useful for treating mixtures containing light organic components, such as ethanol, isopropanol or acetic acid.

Huang, Yu (Palo Alto, CA); Ly, Jennifer (San Jose, CA); Aldajani, Tiem (San Jose, CA); Baker, Richard W. (Palo Alto, CA)

2011-08-23T23:59:59.000Z

24

Compound nuclear decay and the liquid to vapor phase transition: a physical picture  

E-Print Network (OSTI)

Analyses of multifragmentation in terms of the Fisher droplet model (FDM) and the associated construction of a nuclear phase diagram bring forth the problem of the actual existence of the nuclear vapor phase and the meaning of its associated pressure. We present here a physical picture of fragment production from excited nuclei that solves this problem and establishes the relationship between the FDM and the standard compound nucleus decay rate for rare particles emitted in first-chance decay. The compound thermal emission picture is formally equivalent to a FDM-like equilibrium description and avoids the problem of the vapor while also explaining the observation of Boltzmann-like distribution of emission times. In this picture a simple Fermi gas thermometric relation is naturally justified and verified in the fragment yields and time scales. Low energy compound nucleus fragment yields scale according to the FDM and lead to an estimate of the infinite symmetric nuclear matter critical temperature between 18 a...

Moretto, L G; Phair, L

2005-01-01T23:59:59.000Z

25

Inhibition of Pitting and Crevice Corrosion by Filming Amines and Vapor Phase Corrosion Inhibitors  

Science Conference Proceedings (OSTI)

The increase of fossil units that are being removed from service for indeterminate periods due to economic dispatch, seasonal conditions of excess generating capacity, or temporary decommissioning of generating assets necessitates alternative protective measures to prevent and reduce deterioration of the system components during these periods of idle operation. Preservation methods and techniques using vapor phase corrosion inhibitors and film-forming hydrophobic amines may provide an effective alternati...

2012-01-17T23:59:59.000Z

26

Hydride compressor  

DOE Patents (OSTI)

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

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

1978-01-01T23:59:59.000Z

27

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

28

Advanced Hydride Laboratory  

DOE Green Energy (OSTI)

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

Motyka, T.

1989-01-01T23:59:59.000Z

29

Calculation of two-phase dispersed droplet-in-vapor flows including normal shock waves  

DOE Green Energy (OSTI)

A method for calculating quasi-one-dimensional, steady-state, two-phase dispersed droplet-in-vapor flow has been developed. The technique is applicable to both subsonic and supersonic single component flow in which normal shock waves may occur, and is the basis for a two-dimensional model. The flow is assumed to be inviscid except for droplet drag. Temperature and pressure equilibrium between phases is assumed, although this is not a requirement of the technique. Example calculations of flow in one-dimensional nozzles with and without normal shocks are given and compared with experimentally measured pressure profiles for both low quality and high quality two-phase steam/water flow.

Comfort, W.J.; Alger, T.W.; Giedt, W.H.; Crowe, C.T.

1976-07-28T23:59:59.000Z

30

Silica Embedded Metal Hydrides  

DOE Green Energy (OSTI)

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

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

1998-08-01T23:59:59.000Z

31

Compound nuclear decay and the liquid to vapor phase transition: a physical picture  

E-Print Network (OSTI)

Analyses of multifragmentation in terms of the Fisher droplet model (FDM) and the associated construction of a nuclear phase diagram bring forth the problem of the actual existence of the nuclear vapor phase and the meaning of its associated pressure. We present here a physical picture of fragment production from excited nuclei that solves this problem and establishes the relationship between the FDM and the standard compound nucleus decay rate for rare particles emitted in first-chance decay. The compound thermal emission picture is formally equivalent to a FDM-like equilibrium description and avoids the problem of the vapor while also explaining the observation of Boltzmann-like distribution of emission times. In this picture a simple Fermi gas thermometric relation is naturally justified and verified in the fragment yields and time scales. Low energy compound nucleus fragment yields scale according to the FDM and lead to an estimate of the infinite symmetric nuclear matter critical temperature between 18 and 27 MeV depending on the choice of the surface energy coefficient of nuclear matter.

L. G. Moretto; J. B. Elliott; L. Phair

2005-07-08T23:59:59.000Z

32

Gas-phase reaction study of disilane pyrolysis: Applications to low pressure chemical vapor deposition  

SciTech Connect

The gas-phase thermal reactions during disilane decomposition at low pressure chemical vapor deposition conditions were studied from 300 to 1,000 K using resonance enhanced multiphoton ionization (REMPI) and multiphoton ionization (MPI). REMPI of gas-phase Si, mass 28, was detected from 640 to 840 K and 1 to 10 Torr, with a maximum signal intensity between 700 to 720 K. During disilane decomposition, no SiH (427.8 nm), SiH[sub 2] (494-515 nm), or SiH[sub 3] (419.0 nm) was detected. MPI of higher silanes, silenes, and silylenes were detected through mass fragments 2, 32, and 60; these species reached a maximum signal intensity 20 degrees prior to the mass-28 maximum. Modeling studies that included a detailed low pressure gas-phase kinetic scheme predict relative gas-phase partial pressures generated during disilane pyrolysis. The model predicted experimental trends in the Si partial pressure and the higher silane, silene, and silylene partial pressures.

Johannes, J.E.; Ekerdt, J.G. (Univ. of Texas, Austin, TX (United States). Dept. of Chemical Engineering)

1994-08-01T23:59:59.000Z

33

Tank vapor sampling and analysis data package for tank 241-C-106 waste retrieval sluicing system process test phase III  

Science Conference Proceedings (OSTI)

This data package presents sampling data and analytical results from the March 28, 1999, vapor sampling of Hanford Site single-shell tank 241-C-106 during active sluicing. Samples were obtained from the 296-C-006 ventilation system stack and ambient air at several locations. Characterization Project Operations (CPO) was responsible for the collection of all SUMMATM canister samples. The Special Analytical Support (SAS) vapor team was responsible for the collection of all triple sorbent trap (TST), sorbent tube train (STT), polyurethane foam (PUF), and particulate filter samples collected at the 296-C-006 stack. The SAS vapor team used the non-electrical vapor sampling (NEVS) system to collect samples of the air, gases, and vapors from the 296-C-006 stack. The SAS vapor team collected and analyzed these samples for Lockheed Martin Hanford Corporation (LMHC) and Tank Waste Remediation System (TWRS) in accordance with the sampling and analytical requirements specified in the Waste Retrieval Sluicing System Vapor Sampling and Analysis Plan (SAP) for Evaluation of Organic Emissions, Process Test Phase III, HNF-4212, Rev. 0-A, (LMHC, 1999). All samples were stored in a secured Radioactive Materials Area (RMA) until the samples were radiologically released and received by SAS for analysis. The Waste Sampling and Characterization Facility (WSCF) performed the radiological analyses. The samples were received on April 5, 1999.

LOCKREM, L.L.

1999-08-13T23:59:59.000Z

34

Growth of vertical-cavity surface emitting lasers by metalorganic vapor phase epitaxy  

SciTech Connect

We present growth and characterization of visible and near-infrared vertical-cavity surface emitting lasers (VCSELs) grown by metalorganic vapor phase epitaxy. Discussions on the growth issue of VCSEL materials include growth rate and composition control using an {ital in}{ital situ} normal-incidence reflectometer, comprehensive p- and n-type doping study in AlGaAs by CCl{sub 4} and Si{sub 2}H{sub 6} over the entire composition range, and optimization of ultra-high material uniformity. We also demonstrate our recent achievements of all-AlGaAs VCSELs which include the first room-temperature continuous- wave demonstration of 700-nm red VCSELs and high-efficiency and low- threshold voltage 850-nm VCSELs.

Hou, H.Q.; Hammons, B.E.; Crawford, M.H.; Lear, K.L.; Choquette, K.D.

1996-10-01T23:59:59.000Z

35

Computational Modeling of Uranium Hydriding and Complexes  

DOE Green Energy (OSTI)

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

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

2003-02-03T23:59:59.000Z

36

Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System  

DOE Green Energy (OSTI)

This report summarizes work of this project from October 2003 through March 2004. The major focus of the research was to further investigate BTEX removal from produced water, to quantify metal ion removal from produced water, and to evaluate a lab-scale vapor phase bioreactor (VPB) for BTEX destruction in off-gases produced during SMZ regeneration. Batch equilibrium sorption studies were conducted to evaluate the effect of semi-volatile organic compounds commonly found in produced water on the sorption of benzene, toluene, ethylbenzene, and xylene (BTEX) onto surfactant-modified zeolite (SMZ) and to examine selected metal ion sorption onto SMZ. The sorption of polar semi-volatile organic compounds and metals commonly found in produced water onto SMZ was also investigated. Batch experiments were performed in a synthetic saline solution that mimicked water from a produced water collection facility in Wyoming. Results indicated that increasing concentrations of semi-volatile organic compounds increased BTEX sorption. The sorption of phenol compounds could be described by linear isotherms, but the linear partitioning coefficients decreased with increasing pH, especially above the pKa's of the compounds. Linear correlations relating partitioning coefficients of phenol compounds with their respective solubilities and octanol-water partitioning coefficients were developed for data collected at pH 7.2. The sorption of chromate, selenate, and barium in synthetic produced water were also described by Langmuir isotherms. Experiments conducted with a lab-scale vapor phase bioreactor (VPB) packed with foam indicated that this system could achieve high BTEX removal efficiencies once the nutrient delivery system was optimized. The xylene isomers and benzene were found to require the greatest biofilter bed depth for removal. This result suggested that these VOCs would ultimately control the size of the biofilter required for the produced water application. The biofilter recovered rapidly from shutdowns showing that the system was resilient to discontinuous feed conditions therefore provided flexibility on the SMZ regeneration process.

Lynn E. Katz; Kerry A. Kinney; R. S. Bowman; E. J. Sullivan

2004-03-11T23:59:59.000Z

37

Method for the generation of variable density metal vapors which bypasses the liquidus phase  

DOE Patents (OSTI)

The present invention provides a method for producing a metal vapor that includes the steps of combining a metal and graphite in a vessel to form a mixture; heating the mixture to a first temperature in an argon gas atmosphere to form a metal carbide; maintaining the first temperature for a period of time; heating the metal carbide to a second temperature to form a metal vapor; withdrawing the metal vapor and the argon gas from the vessel; and separating the metal vapor from the argon gas. Metal vapors made using this method can be used to produce uniform powders of the metal oxide that have narrow size distribution and high purity.

Kunnmann, Walter (Stony Brook, NY); Larese, John Z. (Rocky Point, NY)

2001-01-01T23:59:59.000Z

38

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

SciTech Connect

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

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

1997-01-01T23:59:59.000Z

39

Transition-Metal Hydrides  

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

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

40

Carbon-Supported bimetallic Pd-Fe catalysts for vapor-phase hydrodeoxygenation of guaiacol  

Science Conference Proceedings (OSTI)

Abstract Carbon supported metal catalysts (Cu/C, Fe/C, Pd/C, Pt/C, PdFe/C and Ru/C) have been prepared, characterized and tested for vapor-phase hydrodeoxygenation (HDO) of guaiacol (GUA) at atmospheric pressure. Phenol was the major intermediate on all catalysts. Over the noble metal catalysts saturation of the aromatic ring was the major pathway observed at low temperature (250 C), forming predominantly cyclohexanone and cyclohexanol. Substantial ring opening reaction was observed on Pt/C and Ru/C at higher reaction temperatures (e.g., 350 C). Base metal catalysts, especially Fe/C, were found to exhibit high HDO activity without ring-saturation or ring-opening with the main products being benzene, phenol along with small amounts of cresol, toluene and trimethylbenzene (TMB). A substantial enhancement in HDO activity was observed on the PdFe/C catalysts. Compared with Fe/C, the yield to oxygen-free aromatic products (i.e., benzene/toluene/TMB) on PdFe/C increased by a factor of four at 350 C, and by approximately a factor of two (83.2% versus 43.3%) at 450 C. The enhanced activity of PdFe/C is attributed to the formation of PdFe alloy as evidenced by STEM, EDS and TPR.

Sun, Junming; Karim, Ayman M.; Zhang, He; Kovarik, Libor; Li, Xiaohong S.; Hensley, Alyssa; McEwen, Jean-Sabin; Wang, Yong

2013-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

Chemistry of intermetallic hydrides  

DOE Green Energy (OSTI)

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

Reilly, J.J.

1991-01-01T23:59:59.000Z

42

Hydride heat pump  

DOE Patents (OSTI)

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

Cottingham, James G. (Center Moriches, NY)

1977-01-01T23:59:59.000Z

43

TREATMENT OF PRODUCED WATERS USING A SURFACTANT MODIFIED ZEOLITE/VAPOR PHASE BIOREACTOR SYSTEM  

DOE Green Energy (OSTI)

Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. It is by some estimates the largest single waste stream in the country, aside from nonhazardous industrial wastes. Characteristics of produced water include high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component, and chemicals added during the oil-production process. While most of the produced water is disposed via reinjection, some of them must be treated to remove organic constituents before the water is discharged. Current treatment options are successful in reducing the organic content; however, they cannot always meet the levels of current or proposed regulations for discharged water. Therefore, an efficient, cost-effective treatment technology is needed. Surfactant-modified zeolite (SMZ) has been used successfully to treat contaminated ground water for organic and inorganic constituents. In addition, the low cost of natural zeolites makes their use attractive in water-treatment applications. Our previous DOE research work (DE-AC26-99BC15221) demonstrated that SMZ could successfully remove BTEX compounds from the produced water. In addition, SMZ could be regenerated through a simple air sparging process. The primary goal of this project is to develop a robust SMZ/VPB treatment system to efficiently remove the organic constituents from produced water in a cost-effective manner. This report summarizes work of this project from October 2002 to March 2003. In this starting stage of this study, we have continued our investigation of SMZ regeneration from our previous DOE project. Two saturation/stripping cycles have been completed for SMZ columns saturated with BTEX compounds. Preliminary results suggest that BTEX sorption actually increases with the number of saturation/regeneration cycles. Furthermore, the experimental vapor phase bioreactors for this project have been designed and are currently being assembled to treat the off-gas from the SMZ regeneration process.

Lynn E. Katz; Kerry A. Kinney; R.S. Bowman; E.J. Sullivan

2003-04-01T23:59:59.000Z

44

Desalination-of water by vapor-phase transport through hydrophobic nanopores  

E-Print Network (OSTI)

We propose a new approach to desalination of water whereby a pressure difference across a vapor-trapping nanopore induces selective transport of water by isothermal evaporation and condensation across the pore. Transport ...

Lee, Jongho

45

Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System  

DOE Green Energy (OSTI)

This report summarizes work performed on this project from October 2004 through March 2005. In previous work, a surfactant modified zeolite (SMZ) was shown to be an effective system for removing BTEX contaminants from produced water. Additional work on this project demonstrated that a compost-based biofilter could biodegrade the BTEX contaminants found in the SMZ regeneration waste gas stream. However, it was also determined that the BTEX concentrations in the waste gas stream varied significantly during the regeneration period and the initial BTEX concentrations were too high for the biofilter to handle effectively. A series of experiments were conducted to determine the feasibility of using a passive adsorption column placed upstream of the biofilter to attenuate the peak gas-phase VOC concentrations delivered to the biofilter during the SMZ regeneration process. In preparation for the field test of the SMZ/VPB treatment system in New Mexico, a pilot-scale SMZ system was also designed and constructed during this reporting period. Finally, a cost and feasibility analysis was also completed. To investigate the merits of the passive buffering system during SMZ regeneration, two adsorbents, SMZ and granular activated carbon (GAC) were investigated in flow-through laboratory-scale columns to determine their capacity to handle steady and unsteady VOC feed conditions. When subjected to a toluene-contaminated air stream, the column containing SMZ reduced the peak inlet 1000 ppmv toluene concentration to 630 ppmv at a 10 second contact time. This level of buffering was insufficient to ensure complete removal in the downstream biofilter and the contact time was longer than desired. For this reason, using SMZ as a passive buffering system for the gas phase contaminants was not pursued further. In contrast to the SMZ results, GAC was found to be an effective adsorbent to handle the peak contaminant concentrations that occur early during the SMZ regeneration process. At a one second residence time, the GAC bed reduced peak contaminant concentrations by 97%. After the initial peak, the inlet VOC concentration in the SMZ regeneration gas stream drops exponentially with time. During this period, the contaminants on the GAC subsequently desorbed at a nearly steady rate over the next 45 hours resulting in a relatively steady effluent concentration of approximately 25 ppm{sub v}. This lower concentration is readily degradable by a downstream vapor phase biofilter (VPB) and the steady nature of the feed stream will prevent the biomass in the VPB from enduring starvation conditions between SMZ regeneration cycles. Repetitive sorption and desorption cycles that would be expected in the field were also investigated. It was determined that although the GAC initially lost some VOC sorption capacity, the adsorption and desorption profiles stabilized after approximately 6 cycles indicating that a GAC bed should be suitable for continuous operation. In preparation for the pilot field testing of the SMZ/VPB system, design, ''in-house'' construction and testing of the field system were completed during this project period. The design of the SMZ system for the pilot test was based on previous investigations by the PI's in Wyoming, 2002 and on analyses of the produced water at the field site in New Mexico. The field tests are scheduled for summer, 2005. A cost survey, feasibility of application and cost analyses were completed to investigate the long term effectiveness of the SMZ/VPB system as a method of treating produced water for re-use. Several factors were investigated, including: current costs to treat and dispose of produced water, end-use water quality requirements, and state and federal permitting requirements.

Soondong Kwon; Elaine B. Darby; Li-Jung Chen; Lynn E. Katz; Kerry A. Kinney; R. S. Bowman; E. J. Sullivan

2005-03-11T23:59:59.000Z

46

TREATMENT OF PRODUCED WATERS USING A SURFACTANT MODIFIED ZEOLITE/VAPOR PHASE BIOREATOR SYSTEM  

DOE Green Energy (OSTI)

Co-produced water from the oil and gas industry is by some estimates the largest single waste stream in the country, aside from nonhazardous industrial wastes. Characteristics of produced water include high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component, and chemicals added during the oil-production process. While most of the produced water is disposed via reinjection, some of them must be treated to remove organic constituents before the water is discharged. An efficient, cost-effective treatment technology is needed to remove these constituents. Surfactant-modified zeolite (SMZ) has been used successfully to treat contaminated ground water for organic and inorganic constituents. In addition, the low cost of natural zeolites makes their use attractive in water-treatment applications. Our previous DOE research work (DE-AC26-99BC15221) demonstrated that SMZ could successfully remove BTEX compounds from the produced water. In addition, SMZ could be regenerated through a simple air sparging process. The primary goal of this project is to develop a robust SMZ/VPB treatment system to efficiently remove the organic constituents from produced water in a cost-effective manner. This report summarizes work of this project from March 2003 through September 2003. We have continued our investigation of SMZ regeneration from our previous DOE project. Ten saturation/stripping cycles have been completed for SMZ columns saturated with BTEX compounds. The results suggest that BTEX sorption capacity is not lost after ten saturation/regeneration cycles. The composition of produced water from a site operated by Crystal Solutions Ltd. in Wyoming has been characterized and was used to identify key semi-volatile components. Isotherms with selected semi-volatile components have been initiated and preliminary results have been obtained. The experimental vapor phase bioreactors for this project have been designed and assembled to treat the off-gas from the SMZ regeneration process. These columns will be used both in the laboratory and in the proposed field testing to be conducted next year. Innocula for the columns that degrade all of the BTEX columns have been developed.

LYNN E. KATZ; KERRY A. KINNEY; R.S. BOWMAN; E.J. SULLIVAN

2003-10-01T23:59:59.000Z

47

Treatment of Produced Water Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System  

DOE Green Energy (OSTI)

Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. Produced waters typically contain a high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component as well as chemicals added during the oil-production process. It has been estimated that a total of 14 billion barrels of produced water were generated in 2002 from onshore operations (Veil, 2004). Although much of this produced water is disposed via reinjection, environmental and cost considerations can make surface discharge of this water a more practical means of disposal. In addition, reinjection is not always a feasible option because of geographic, economic, or regulatory considerations. In these situations, it may be desirable, and often necessary from a regulatory viewpoint, to treat produced water before discharge. It may also be feasible to treat waters that slightly exceed regulatory limits for re-use in arid or drought-prone areas, rather than losing them to reinjection. A previous project conducted under DOE Contract DE-AC26-99BC15221 demonstrated that surfactant modified zeolite (SMZ) represents a potential treatment technology for produced water containing BTEX. Laboratory and field experiments suggest that: (1) sorption of benzene, toluene, ethylbenzene and xylenes (BTEX) to SMZ follows linear isotherms in which sorption increases with increasing solute hydrophobicity; (2) the presence of high salt concentrations substantially increases the capacity of the SMZ for BTEX; (3) competitive sorption among the BTEX compounds is negligible; and, (4) complete recovery of the SMZ sorption capacity for BTEX can be achieved by air sparging the SMZ. This report summarizes research for a follow on project to optimize the regeneration process for multiple sorption/regeneration cycles, and to develop and incorporate a vapor phase bioreactor (VPB) system for treatment of the off-gas generated during air sparging. To this end, we conducted batch and column laboratory SMZ and VPB experiments with synthetic and actual produced waters. Based on the results of the laboratory testing, a pilot scale study was designed and conducted to evaluate the combined SMZ/VPB process. An economic and regulatory feasibility analysis was also completed as part of the current study to assess the viability of the process for various water re-use options.

Lynn E. Katz; Kerry A. Kinney; Robert S. Bowman; Enid J. Sullivan; Soondong Kwon; Elaine B. Darby; Li-Jung Chen; Craig R. Altare

2006-01-31T23:59:59.000Z

48

Evaluation of Catalysts from Different Origin for Vapor Phase Upgrading in Biomass Pyrolysis  

SciTech Connect

Liquid fuels and chemicals from biomass resources arouse much interests in research and development. Fast pyrolysis of biomass has the potential to effectively change solid biomass materials into liquid products. However, bio-oil from traditional pyrolysis processes is difficult to apply in industry, because of its complicated composition, high oxygen content, low stability, etc. Upgrading or refining of the bio-oil should be performed for industrial application of biomass pyrolysis. Often, the process would be done in a separate reactor downstream of the pyrolysis process. In this paper, a laboratory scale micro test facility was constructed, wherein the pyrolysis of pine and catalytic upgrading of the resulting vapors were closely coupled in one reactor. The composition of vapor effluent was monitored with a molecular beam mass spectrometer (MBMS) for the online evaluation of the catalyst performance. Catalysts from different origin were tested and compared for the effectiveness of pyrolysis vapor upgrading, namely commercial zeolites, Ni based steam reforming catalyst, CaO, MgO, and several laboratory-made catalysts. The reaction temperature for catalytic upgrading varied between 400 and 600 centigrade, and the gaseous residence time ranged from 0.1 second to above 2 second, to simulate the conditions in industrial application. It is revealed that some catalysts are active in transform most of primary biomass pyrolysis vapors into hydrocarbons, resulting in nonoxygenated products, which is beneficial for downstream utilization. Others are not as effective, results in minor improvement compared with blank test results.

Zhang, X.; Mukarakate, C.; Zheng, Z.; Nimlos, M.

2012-01-01T23:59:59.000Z

49

Boron hydride polymer coated substrates  

DOE Patents (OSTI)

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

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

1986-08-27T23:59:59.000Z

50

Boron hydride polymer coated substrates  

DOE Patents (OSTI)

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

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

1987-01-01T23:59:59.000Z

51

Vapor-Phase-Deposited Organosilane Coatings as "Hardening" Agents for High-Peak-Power Laser Optics  

Science Conference Proceedings (OSTI)

Multilayer-dielectric (MLD) diffraction gratings are used in high-power laser systems to compress laser-energy pulses. The peak power deliverable on target for these short-pulse petawatt class systems is limited by the laser-damage resistance of the optical components in the system, especially the MLD gratings. Recent experiments in our laboratory have shown that vapor treatment of MLD gratings at room temperature with organosilanes such as hexamethyldisilazane (HMDS) produces an increase in their damage threshold as compared to uncoated MLD grating control samples.

Marshall, K.L.; Culakova, Z.; Ashe, B.; Giacofei, C.; Rigatti, A.L.; Kessler, T.J.; Schmid, A.W.; Oliver, J.B.; Kozlov, A.

2008-01-07T23:59:59.000Z

52

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

53

Activated aluminum hydride hydrogen storage compositions and ...  

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

54

Dimensionally stable metal hydrides - major problem with hydrides is resolved  

SciTech Connect

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

McCarthy, K.

1995-11-01T23:59:59.000Z

55

Enhanced quality thin film Cu(In,Ga)Se.sub.2 for semiconductor device applications by vapor-phase recrystallization  

DOE Patents (OSTI)

Enhanced quality thin films of Cu.sub.w (In,Ga.sub.y)Se.sub.z for semiconductor device applications are fabricated by initially forming a Cu-rich, phase-separated compound mixture comprising Cu(In,Ga):Cu.sub.x Se on a substrate to form a large-grain precursor and then converting the excess Cu.sub.x Se to Cu(In,Ga)Se.sub.2 by exposing it to an activity of In and/or Ga, either in vapor In and/or Ga form or in solid (In,Ga).sub.y Se.sub.z. Alternatively, the conversion can be made by sequential deposition of In and/or Ga and Se onto the phase-separated precursor. The conversion process is preferably performed in the temperature range of about 300.degree.-600.degree. C., where the Cu(In,Ga)Se.sub.2 remains solid, while the excess Cu.sub.x Se is in a liquid flux. The characteristic of the resulting Cu.sub.w (In,Ga).sub.y Se.sub.z can be controlled by the temperature. Higher temperatures, such as 500.degree.-600.degree. C., result in a nearly stoichiometric Cu(In,Ga)Se.sub.2, whereas lower temperatures, such as 300.degree.-400.degree. C., result in a more Cu-poor compound, such as the Cu.sub.z (In,Ga).sub.4 Se.sub.7 phase.

Tuttle, John R. (Denver, CO); Contreras, Miguel A. (Golden, CO); Noufi, Rommel (Golden, CO); Albin, David S. (Denver, CO)

1994-01-01T23:59:59.000Z

56

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

SciTech Connect

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

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

2012-10-23T23:59:59.000Z

57

Dimensionally stable metallic hydride composition  

SciTech Connect

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

Heung, Leung K. (Aiken, SC)

1994-01-01T23:59:59.000Z

58

Dimensionally stable metallic hydride composition  

SciTech Connect

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

Heung, L.K.

1994-03-22T23:59:59.000Z

59

Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System  

SciTech Connect

This report summarizes work performed on this project from April 2004 through September 2004. Our previous work demonstrated that a polyurethane foam biofilter could successfully biodegrade the BTEX contaminants found in the SMZ regeneration waste gas stream. However, establishing the biomass on the polyurethane foam packing was relatively time consuming and daily recirculation of a concentrated nutrient solution was required for efficient operation of the foam biofilter. To simplify the start up and operating requirements of the biofilter system, a simple, compost-based biofilter was investigated for its ability to treat the BTEX contaminants generated during the SMZ regeneration process. The investigation of the compost biofilter was divided into three experimental phases that spanned 180 days of biofilter operation. During Phase 1, the biofilter was continuously supplied a BTEX-contaminated waste gas stream. During Phase 2, a series of periodic shutdown tests were conducted to assess how the biofilter responded when the BTEX feed was discontinued for periods ranging from 1 day to 2.8 days. The Phase 3 experiments focused on determining how the biofilter would handle periodic spikes in inlet BTEX concentration as would be expected when it is coupled with an SMZ column. Results from the continuous feed (Phase 1) experiments demonstrated that the compost biofilter could maintain BTEX removals of greater than 98% within two weeks of startup. Results of the shutdown experiments indicated that benzene removal was the most sensitive to interruptions in the BTEX feed. Nevertheless, the BTEX removal efficiency exceeded 95% within 6 hours of reestablishing the BTEX feed to the biofilter. When the biofilter was subjected to periodic spikes in BTEX concentration (Phase 3), it was found that the total BTEX removal efficiency stabilized at approximately 75% despite the fact that the biofilter was only fed BTEX contaminants 8 hours per day. Finally, the effects of nutrient supply and EBCT on compost biofilter performance were also investigated. The bioreactor maintained greater than 95% removal efficiency for over 40 days without an additional supply of nutrients when a 10X concentrated HCMM was mixed with the compost packing at the beginning of the experiments. Results also suggest that an EBCT greater than 30 seconds is required to maintain high BTEX removal efficiencies in the compost biofilter system.

Lynn E. Katz; Kerry A. Kinney; R. S. Bowman; E. J. Sullivan

2004-09-11T23:59:59.000Z

60

Erbium hydride decomposition kinetics.  

DOE Green Energy (OSTI)

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

Ferrizz, Robert Matthew

2006-11-01T23:59:59.000Z

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


61

Complex Hydrides for Hydrogen Storage  

DOE Green Energy (OSTI)

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

Slattery, Darlene; Hampton, Michael

2003-03-10T23:59:59.000Z

62

Transition between the 1 x 1 and ({radical}3 x 2{radical}3)R30{degree} surface structures of GaN in the vapor-phase environment  

SciTech Connect

Out-of-plane structures of the GaN(0001) surface in the metal-organic chemical vapor deposition (MOCVD) environment have been determined using in situ grazing-incidence X-ray scattering. The authors measured 11{bar 2}{ell} crystal truncation rod intensities at a variety of temperatures and ammonia partial pressures on both sides of the 1 x 1 to ({radical}3 x 2{radical}3)R30{degree} surface phase transition. The out-of-plane structure of the ({radical}3 x 2{radical}3)R30{degree} phase appears to be nearly independent of temperature below the transition, while the structure of the 1 x 1 phase changes increase rapidly as the phase transition is approached from above. A model for the structure of the 1 x 1 phase with a partially-occupied top Ga layer agrees well with the data. The observed temperature dependence is consistent with a simple model of the equilibrium between the vapor phase and the surface coverage of Ga and N. In addition, the authors present results on the kinetics of reconstruction domain coarsening following a quench into the ({radical}3 x 2{radical}3)R30{degree} phase field.

Munkholm, A.; Thompson, C.; Stephenson, G. B.; Eastman, J. A.; Auciello, O.; Fini, P.; Speck, J. S.; DenBaars, S. P.

2000-01-12T23:59:59.000Z

63

Journal of Light Emitting Diodes Vol 2 N0 1, April 2010 1 Abstract--In metal organic vapor phase epitaxy we developed  

E-Print Network (OSTI)

Journal of Light Emitting Diodes Vol 2 N0 1, April 2010 1 Abstract-- In metal organic vapor phase epitaxy we developed GaInN/GaN quantum well material suitable for 500 ­ 580 nm light emitting diodes at longer wavelengths. Index Terms-- a-plane GaN, GaInN, Green light emitting diode, m-plane GaN I

Wetzel, Christian M.

64

Hydride Rim Formation in Unirradiated Zircaloy  

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

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

65

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

66

Method of producing a chemical hydride  

DOE Patents (OSTI)

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

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

2007-11-13T23:59:59.000Z

67

Uranium Powder Production Via Hydride Formation and Alpha Phase Sintering of Uranium and Uranium-zirconium Alloys for Advanced Nuclear Fuel Applications  

E-Print Network (OSTI)

The research in this thesis covers the design and implementation of a depleted uranium (DU) powder production system and the initial results of a DU-Zr-Mg alloy alpha phase sintering experiment where the Mg is a surrogate for Pu and Am. The powder production system utilized the uranium hydrogen interaction in order to break down larger pieces of uranium into fine powder. After several iterations, a successful reusable system was built. The nominal size of the powder product was on the order of 1 to 3 mm. The resulting uranium powder was pressed into pellets of various compositions (DU, DU-10Zr, DU-Mg, DU-10Zr-Mg) and heated to approximately 650?C, just below the alphabeta phase transition of uranium. The dimensions of the pellets were measured before and after heating and in situ dimension changes were measured using a linear variable differential transducer (LVDT). Post experiment measurement of the pellets proved to be an unreliable indicator of sintering do the cracking of the pellets during cool down. The cracking caused increases in the diameter and height of the samples. The cracks occurred in greater frequency along the edges of the pellets. All of the pellets, except the DU-10Zr-Mg pellet, were slightly conical in shape. This is believed to be an artifact of the powder pressing procedure. A greater density occurs on one end of the pellet during pressing and thus leads to gradient in the sinter rate of the pellet. The LVDT measurements proved to be extremely sensitive to outside vibration, making a subset of the data inappropriate for analysis. The pellets were also analyzed using electron microscopy. All pellets showed signs of sintering and an increase in density. The pellets will the greatest densification and lowest porosity were the DU-Mg and DU-10Zr-Mg. The DU-Mg pellet had a porosity of 14 +or- 2.%. The DU-10Zr-Mg porosity could not be conclusively determined due to lack of clearly visible pores in the image, however there were very few pores indicating a high degree of sintering. In the DU-10Zr-Mg alloy, large grains of DU were surrounded by Zr. This phenomena was not present in the DU-10Zr pellet where the Zr and DU stayed segregated. There was no indication of alloying between the Zr and DU in pellets.

Garnetti, David J.

2009-12-01T23:59:59.000Z

68

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

69

Diffusional exchange of isotopes in a metal hydride sphere.  

DOE Green Energy (OSTI)

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

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

2011-04-01T23:59:59.000Z

70

Complex Hydrides for Hydrogen Storage  

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

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

71

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

72

Vapor Degreasing  

Science Conference Proceedings (OSTI)

Table 6   Applications of vapor degreasing by vapor-spray-vapor systems...hardware Brass 2270 5000 Buffing compound; rouge Lacquer spray Racked work on continuous monorail Acoustic ceiling tile Steel 2720 6000 Light oil (stamping lubricant) Painting Monorail conveyor Gas meters Terneplate 4540 10,000 Light oil Painting Monorail conveyor Continuous strip, 0.25??4.1 mm...

73

Vapor Characterization  

Science Conference Proceedings (OSTI)

... thermodynamics (that is, vapor liquid equilibrium) as ... of solids and low volatility liquids is extraordinarily ... such situations is the gas saturation method ...

2013-12-10T23:59:59.000Z

74

Activated Aluminum Hydride Hydrogen Storage Compositions ...  

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

75

Hydrogen Storage property of sandwiched magnesium hydride naoparticle...  

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

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

76

ENVIRONMENTAL REACTIVITY OF SOLID STATE HYDRIDE MATERIALS  

DOE Green Energy (OSTI)

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

Gray, J; Donald Anton, D

2009-04-23T23:59:59.000Z

77

Hydrogen storage technology for metal hydrides  

DOE Green Energy (OSTI)

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

Strickland, G

1978-06-01T23:59:59.000Z

78

Determination of the adsorptive capacity and adsorption isotherm of vapor-phase mercury chloride on powdered activated carbon using thermogravimetric analysis  

Science Conference Proceedings (OSTI)

This study investigated the use of thermogravimetric analysis (TGA) to determine the adsorptive capacity and adsorption isotherm of vapor-phase mercury chloride on powdered activated carbon (PAC). The technique is commonly applied to remove mercury-containing air pollutants from gas streams emitted from municipal solid waste incinerators. An alternative form of powdered activated carbon derived from a pyrolyzed tire char was prepared for use herein. The capacity of waste tire-derived PAC to adsorb vapor-phase HgCl{sub 2} was successfully measured using a self-designed TGA adsorption system. Experimental results showed that the maximum adsorptive capacities of HgCl{sub 2} were 1.75, 0.688, and 0.230 mg of HgCl{sub 2} per gram of powdered activated carbon derived from carbon black at 30, 70, and 150{sup o} for 500 {mu}g/m{sup 3} of HgCl{sub 2}, respectively. Four adsorption isotherms obtained using the Langmuir, Freundlich, Redlich-Peterson, and Brunauer-Emmett-eller (BET) models were used to simulate the adsorption of HgCl{sub 2}. The comparison of experimental data associated with the four adsorption isotherms indicated that BET fit the experimental results better than did the other isotherms at 30{sup o}, whereas the Freundlich isotherm fit the experimental results better at 70 and 150{sup o}. Furthermore, the calculations of the parameters associated with Langmuir and Freundlich isotherms revealed that the adsorption of HgCl{sub 2} by PAC-derived carbon black favored adsorption at various HgCl{sub 2} concentrations and temperatures. 35 refs., 7 figs., 3 tabs.

Hsun-Yu Lin; Chung-Shin Yuan; Wei-Ching Chen; Chung-Hsuang Hung [National Sun Yat-Sen University, Taiwan (China). Institute of Environmental Engineering

2006-11-15T23:59:59.000Z

79

Experimental and Modeling Study of the Flammability of Fuel Tank Headspace Vapors from Ethanol/Gasoline Fuels, Phase 2: Evaluations of Field Samples and Laboratory Blends  

DOE Green Energy (OSTI)

Study to measure the flammability of gasoline/ethanol fuel vapors at low ambient temperatures and develop a mathematical model to predict temperatures at which flammable vapors were likely to form.

Gardiner, D. P.; Bardon, M. F.; LaViolette, M.

2010-04-01T23:59:59.000Z

80

Hydrogenation using hydrides and acid  

DOE Patents (OSTI)

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

Bullock, R.M.

1989-12-13T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

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

82

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

83

Hydrogen-storing hydride complexes  

SciTech Connect

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

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

2012-04-10T23:59:59.000Z

84

Chemical Hydride Slurry for Hydrogen Production and Storage  

DOE Green Energy (OSTI)

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

McClaine, Andrew W.

2008-09-30T23:59:59.000Z

85

Quantitative Vapor-phase IR Intensities and DFT Computations to Predict Absolute IR Spectra based on Molecular Structure: I. Alkanes  

SciTech Connect

Recently recorded quantitative IR spectra of a variety of gas-phase alkanes are shown to have integrated intensities in both the C-H stretching and C-H bending regions that depend linearly on the molecular size, i.e. the number of C-H bonds. This result is well predicted from CH4 to C15H32 by DFT computations of IR spectra at the B3LYP/6-31+G(d,p) level of DFT theory. A simple model predicting the absolute IR band intensities of alkanes based only on structural formula is proposed: For the C-H stretching band near 2930 cm-1 this is given by (in km/mol): CH_str = (343)*CH (4160) where CH is number of C-H bonds in the alkane. The linearity is explained in terms of coordinated motion of methylene groups rather than the summed intensities of autonomous -CH2- units. The effect of alkyl chain length on the intensity of a C-H bending mode is explored and interpreted in terms of conformer distribution. The relative intensity contribution of a methyl mode compared to the total C-H stretch intensity is shown to be linear in the number of terminal methyl groups in the alkane, and can be used to predict quantitative spectra a priori based on structure alone.

Williams, Stephen D.; Johnson, Timothy J.; Sharpe, Steven W.; Yavelak, Veronica; Oats, R. P.; Brauer, Carolyn S.

2013-11-13T23:59:59.000Z

86

Growth and characterization of In{sub 0.2}Ga{sub 0.8}Sb device structures using metalorganic vapor phase epitaxy  

DOE Green Energy (OSTI)

In{sub 0.2}Ga{sub 0.8}Sb epitaxial layers and thermophotovoltaic (TPV) device structures have been grown on GaSb and GaAs substrates by metalorganic vapor phase epitaxy (MOVPE). Control of the n-type doping up to 1 {times} 10{sup 18} cm{sup {minus}3} was achieved using diethyltellurium (DETE) as the dopant source. A Hall mobility of greater than 8,000 cm{sup 2}/Vs at 77 K was obtained for a 3 {times} 10{sup 17} cm{sup {minus}3} doped In{sub 0.2}Ga{sub 0.8}Sb layer grown on high-resistivity GaSb substrate. The In{sub 0.2}Ga{sub 0.8}Sb epilayers directly grown on GaSb substrates were tilted with respect to the substrates, with the amount of tilt increasing with the layer thickness. Transmission electron microscopy (TEM) studies of the layers showed the presence of dislocation networks across the epilayers parallel to the interface at different distances from the interface, but the layers above this dislocation network were virtually free of dislocations. A strong correlation between epilayer tilt and TPV device properties was found, with layers having more tilt providing better devices. The results suggest that the dislocations moving parallel to the interface cause lattice tilt, and control of this layer tilt may enable the fabrication of better quality device structures.

Ehsani, H.; Bhat, I.; Hitchcock, C.; Gutmann, R. [Rensselaer Polytechnic Inst., Troy, NY (United States); Charache, G.; Freeman, M. [Lockheed Martin Inc., Schenectady, NY (United States)

1997-05-01T23:59:59.000Z

87

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

88

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

89

Using Metal Hydride to Store Hydrogen  

DOE Green Energy (OSTI)

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

Heung, L.K.

2003-03-12T23:59:59.000Z

90

Impact of nonaqueous phase liquid (NAPL) source zone architecture on mass removal mechanisms in strongly layered heterogeneous porous media during soil vapor extraction  

Science Conference Proceedings (OSTI)

An existing multiphase flow simulator was modified in order to determine the effects of four mechanisms on NAPL mass removal in a strongly layered heterogeneous vadose zone during soil vapor extraction (SVE): a) NAPL flow, b) diffusion and dispersion from low permeability zones, c) slow desorption from sediment grains, and d) rate-limited dissolution of trapped NAPL. The impact of water and NAPL saturation distribution, NAPL type (i.e., free, residual, or trapped) distribution, and spatial heterogeneity of the permeability field on these mechanisms were evaluated. Two different initial source zone architectures (one with and one without trapped NAPL) were considered and these architectures were used to evaluate seven different SVE scenarios. For all runs, slow diffusion from low permeability zones that gas flow bypassed was a dominant factor for diminished SVE effectiveness at later times. This effect was more significant at high water saturation due to the decrease of gas-phase relative permeability. Transverse dispersion contributed to fast NAPL mass removal from the low permeability layer in both source zone architectures, but longitudinal dispersion did not affect overall mass removal time. Both slow desorption from sediment grains and rate-limited mass transfer from trapped NAPL only marginally affected removal times. However, mass transfer from trapped NAPL did affect mass removal at late time, as well as the NAPL distribution. NAPL flow from low to high permeability zones contributed to faster mass removal from the low permeability layer, and this effect increased when water infiltration was eliminated. These simulations indicate that if trapped NAPL exists in heterogeneous porous media, mass transfer can be improved by delivering gas directly to zones with trapped NAPL and by lowering the water content, which increases the gas relative permeability and changes trapped NAPL to free NAPL.

Yoon, Hongkyu; Werth, Charlie; Valocchi, Albert J.; Oostrom, Martinus

2008-09-26T23:59:59.000Z

91

Mathematical modeling of the nickel/metal hydride battery system  

DOE Green Energy (OSTI)

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

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

1995-09-01T23:59:59.000Z

92

METAL ORGANIC VAPOR PHASE EPITAXY  

Science Conference Proceedings (OSTI)

Jun 4, 2004 ... used to texture the surface of a Light Emitting Diode (LED) structure, enhancing light extraction by a factor of 2 to 3 times. This paper will.

93

Long Term Field Development of a Surfactant Modified Zeolite/Vapor Phase Bioreactor System for Treatment of Produced Waters for Power Generation  

Science Conference Proceedings (OSTI)

The main goal of this research was to investigate the feasibility of using a combined physicochemical/biological treatment system to remove the organic constituents present in saline produced water. In order to meet this objective, a physical/chemical adsorption process was developed and two separate biological treatment techniques were investigated. Two previous research projects focused on the development of the surfactant modified zeolite adsorption process (DE-AC26-99BC15221) and development of a vapor phase biofilter (VPB) to treat the regeneration off-gas from the surfactant modified zeolite (SMZ) adsorption system (DE-FC26-02NT15461). In this research, the SMZ/VPB was modified to more effectively attenuate peak loads and to maintain stable biodegradation of the BTEX constituents from the produced water. Specifically, a load equalization system was incorporated into the regeneration flow stream. In addition, a membrane bioreactor (MBR) system was tested for its ability to simultaneously remove the aromatic hydrocarbon and carboxylate components from produced water. The specific objectives related to these efforts included the following: (1) Optimize the performance VPBs treating the transient loading expected during SMZ regeneration: (a) Evaluate the impact of biofilter operating parameters on process performance under stable operating conditions. (b) Investigate how transient loads affect biofilter performance, and identify an appropriate technology to improve biological treatment performance during the transient regeneration period of an SMZ adsorption system. (c) Examine the merits of a load equalization technology to attenuate peak VOC loads prior to a VPB system. (d) Evaluate the capability of an SMZ/VPB to remove BTEX from produced water in a field trial. (2) Investigate the feasibility of MBR treatment of produced water: (a) Evaluate the biodegradation of carboxylates and BTEX constituents from synthetic produced water in a laboratory-scale MBR. (b) Evaluate the capability of an SMZ/MBR system to remove carboxylates and BTEX from produced water in a field trial. Laboratory experiments were conducted to provide a better understanding of each component of the SMZ/VPB and SMZ/MBR process. Laboratory VPB studies were designed to address the issue of influent variability and periodic operation (see DE-FC26-02NT15461). These experiments examined multiple influent loading cycles and variable concentration loadings that simulate air sparging as the regeneration option for the SMZ system. Two pilot studies were conducted at a produced water processing facility near Farmington, New Mexico. The first field test evaluated SMZ adsorption, SMZ regeneration, VPB buffering, and VPB performance, and the second test focused on MBR and SMZ/MBR operation. The design of the field studies were based on the results from the previous field tests and laboratory studies. Both of the biological treatment systems were capable of removing the BTEX constituents in the laboratory and in the field over a range of operating conditions. For the VPB, separation of the BTEX constituents from the saline aqueous phase yielded high removal efficiencies. However, carboxylates remained in the aqueous phase and were not removed in the combined VPB/SMZ system. In contrast, the MBR was capable of directly treating the saline produced water and simultaneously removing the BTEX and carboxylate constituents. The major limitation of the MBR system is the potential for membrane fouling, particularly when the system is treating produced water under field conditions. The combined process was able to effectively pretreat water for reverse osmosis treatment and subsequent downstream reuse options including utilization in power generation facilities. The specific conclusions that can be drawn from this study are summarized.

Lynn Katz; Kerry Kinney; Robert Bowman; Enid Sullivan; Soondong Kwon; Elaine Darby; Li-Jung Chen; Craig Altare

2007-12-31T23:59:59.000Z

94

Hydrogen isotope exchange in metal hydride columns  

DOE Green Energy (OSTI)

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

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

1977-11-21T23:59:59.000Z

95

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

96

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

DOE Green Energy (OSTI)

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

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

1987-12-01T23:59:59.000Z

97

Structural TEM study of nonpolar a-plane gallium nitride grown on (112_0) 4H-SiC by organometallic vapor phase epitaxy  

E-Print Network (OSTI)

nitride grown on (1120) 4H-SiC by organometallic vapor phasea-plane GaN grown on a 4H-SiC substrate with an AlN buffergrown on (0001) Al 2 O 3 , 6H-SiC or free- standing GaN

Zakharov, Dmitri N.; Liliental-Weber, Zuzanna; Wagner, Brian; Reitmeier, Zachary J.; Preble, Edward A.; Davis, Robert F.

2005-01-01T23:59:59.000Z

98

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

DOE Green Energy (OSTI)

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

Beck, R.L.

1960-11-01T23:59:59.000Z

99

Pine Pyrolysis Vapor Phase Upgrading Over ZSM-5 Catalyst: Effect of Temperature, Hot Gas Filtration, and Hydrogen Donor Molecule on the Rate of Deactivation of Catalyst  

SciTech Connect

The conversion of primary vapors from pine pyrolysis over a ZSM-5 catalyst was characterized using a micro-reactor coupled to a molecular beam mass spectrometer (MBMS) to allow on-line measurement of the upgraded vapors. This micro-reacor-MBMS system was used to investigate the effects of hot gas filtration, temperature and hydrogen donor molecules on the rate of deactivation of the UPV2 catalyst. Our results show that the life of catalyst is significantly improved by using better filtration. Temperature had an effect on both product distribution and catalyst deactivation. The hydrogen donor molecules (HDM) used in this study show better reduction in catalyst deactivation rates at high temperatures.

Mukarakate, C.; Zhang, X.; Nimlos, M.; Robichaud, D.; Donohoe, B.

2013-01-01T23:59:59.000Z

100

Image Storage in Hot Vapors  

E-Print Network (OSTI)

We theoretically investigate image propagation and storage in hot atomic vapor. A $4f$ system is adopted for imaging and an atomic vapor cell is placed over the transform plane. The Fraunhofer diffraction pattern of an object in the object plane can thus be transformed into atomic Raman coherence according to the idea of ``light storage''. We investigate how the stored diffraction pattern evolves under diffusion. Our result indicates, under appropriate conditions, that an image can be reconstructed with high fidelity. The main reason for this procedure to work is the fact that diffusion of opposite-phase components of the diffraction pattern interfere destructively.

Zhao, L; Xiao, Y; Yelin, S F

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

Image Storage in Hot Vapors  

E-Print Network (OSTI)

We theoretically investigate image propagation and storage in hot atomic vapor. A $4f$ system is adopted for imaging and an atomic vapor cell is placed over the transform plane. The Fraunhofer diffraction pattern of an object in the object plane can thus be transformed into atomic Raman coherence according to the idea of ``light storage''. We investigate how the stored diffraction pattern evolves under diffusion. Our result indicates, under appropriate conditions, that an image can be reconstructed with high fidelity. The main reason for this procedure to work is the fact that diffusion of opposite-phase components of the diffraction pattern interfere destructively.

L. Zhao; T. Wang; Y. Xiao; S. F. Yelin

2007-10-22T23:59:59.000Z

102

Recovering hydrogen from gas stream using metal hydride  

SciTech Connect

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

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

1982-11-23T23:59:59.000Z

103

Calibrated vapor generator source  

DOE Patents (OSTI)

A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet.

Davies, John P. (Idaho Falls, ID); Larson, Ronald A. (Idaho Falls, ID); Goodrich, Lorenzo D. (Shelley, ID); Hall, Harold J. (Idaho Falls, ID); Stoddard, Billy D. (Idaho Falls, ID); Davis, Sean G. (Idaho Falls, ID); Kaser, Timothy G. (Idaho Falls, ID); Conrad, Frank J. (Albuquerque, NM)

1995-01-01T23:59:59.000Z

104

Calibrated vapor generator source  

DOE Patents (OSTI)

A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet. 10 figs.

Davies, J.P.; Larson, R.A.; Goodrich, L.D.; Hall, H.J.; Stoddard, B.D.; Davis, S.G.; Kaser, T.G.; Conrad, F.J.

1995-09-26T23:59:59.000Z

105

Dissipative hydride precipitates in superconducting niobium cavities  

Science Conference Proceedings (OSTI)

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

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

2011-10-01T23:59:59.000Z

106

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

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

107

Materials compatibility of hydride storage materials with austenitic stainless steels  

DOE Green Energy (OSTI)

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

Clark, E.A.

1992-09-21T23:59:59.000Z

108

Materials compatibility of hydride storage materials with austenitic stainless steels  

DOE Green Energy (OSTI)

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

Clark, E.A.

1992-09-21T23:59:59.000Z

109

METHOD AND APPARATUS FOR MAKING URANIUM-HYDRIDE COMPACTS  

DOE Patents (OSTI)

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

Wellborn, W.; Armstrong, J.R.

1959-03-10T23:59:59.000Z

110

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

Science Conference Proceedings (OSTI)

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

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

111

Low temperature metal-organic chemical vapor deposition growth processes for high-efficiency solar cells  

DOE Green Energy (OSTI)

This report describes the results of a program to develop a more complete understanding of the physical and chemical processes involved in low-temperature growth of III-V compounds by metal-organic chemical vapor deposition (MOCVD) and to develop a low-temperature process that is suitable for the growth of high-efficiency solar cells. The program was structured to develop a better understanding of the chemical reactions involved in MOCVD growth, to develop a model of the processes occurring in the gas phase, to understand the physical kinetics and reactions operative on the surface of the growing crystal, and to develop an understanding of the means by which these processes may be altered to reduce the temperature of growth and the utilization of toxic hydrides. The basic approach was to develop the required information about the chemical and physical kinetics operative in the gas phase and on the surface by the direct physical measurement of the processes whenever possible. The program included five tasks: (1) MOCVD growth process characterization, (2) photoenhanced MOCVD studies, (3) materials characterization, (4) device fabrication and characterization, and (5) photovoltaic training. Most of the goals of the program were met and significant progress was made in defining an approach that would allow both high throughput and high uniformity growth of compound semiconductors at low temperatures. The technical activity was focused on determining the rates of thermal decomposition of trimethyl gallium, exploring alternate arsenic sources for use MOCVD, and empirical studies of atomic layer epitaxy as an approach.

Dapkus, P.D. (University of Southern California, Los Angeles, CA (United States))

1993-02-01T23:59:59.000Z

112

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

SciTech Connect

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

None

2011-12-05T23:59:59.000Z

113

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

114

Nano-engineering of magnesium hydride for hydrogen storage  

Science Conference Proceedings (OSTI)

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

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

2009-04-01T23:59:59.000Z

115

Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of  

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

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

116

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

117

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

118

Recent advances in metal hydrides for clean energy applications  

SciTech Connect

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

Ronnebro, Ewa; Majzoub, Eric H.

2013-06-01T23:59:59.000Z

119

Modular hydride beds for mobile applications  

DOE Green Energy (OSTI)

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

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

1997-08-01T23:59:59.000Z

120

Mercury Vapor Pressure Correlation  

Science Conference Proceedings (OSTI)

An apparent difference between the historical mercury vapor concentration equations used by the mercury atmospheric measurement community ...

2012-10-09T23:59:59.000Z

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


121

Complex Hydride Compounds with Enhanced Hydrogen Storage Capacity  

DOE Green Energy (OSTI)

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

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

2008-02-18T23:59:59.000Z

122

Multicomponent fuel vaporization at high pressures.  

DOE Green Energy (OSTI)

We extend our multicomponent fuel model to high pressures using a Peng-Robinson equation of state, and implement the model into KIVA-3V. Phase equilibrium is achieved by equating liquid and vapor fugacities. The latent heat of vaporization and fuel enthalpies are also corrected for at high pressures. Numerical simulations of multicomponent evaporation are performed for single droplets for a diesel fuel surrogate at different pressures.

Torres, D. J. (David J.); O'Rourke, P. J. (Peter J.)

2002-01-01T23:59:59.000Z

123

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

DOE Green Energy (OSTI)

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

Sapru, K.

1998-12-04T23:59:59.000Z

124

Urania vapor composition at very high temperatures  

SciTech Connect

Due to the chemically unstable nature of uranium dioxide its vapor composition at very high temperatures is, presently, not sufficiently studied though more experimental knowledge is needed for risk assessment of nuclear reactors. We used laser vaporization coupled to mass spectrometry of the produced vapor to study urania vapor composition at temperatures in the vicinity of its melting point and higher. The very good agreement between measured melting and freezing temperatures and between partial pressures measured on the temperature increase and decrease indicated that the change in stoichiometry during laser heating was very limited. The evolutions with temperature (in the range 2800-3400 K) of the partial pressures of the main vapor species (UO{sub 2}, UO{sub 3}, and UO{sub 2}{sup +}) were compared with theoretically predicted evolutions for equilibrium noncongruent gas-liquid and gas-solid phase coexistences and showed very good agreement. The measured main relative partial pressure ratios around 3300 K all agree with calculated values for total equilibrium between condensed and vapor phases. It is the first time the three main partial pressure ratios above stoichiometric liquid urania have been measured at the same temperature under conditions close to equilibrium noncongruent gas-liquid phase coexistence.

Pflieger, Rachel [Institute for Transuranium Elements, Joint Research Centre, European Commission, P.O. Box 2340, 76125 Karlsruhe (Germany); Marcoule Institute for Separation Chemistry (ICSM), UMR 5257, CEA-CNRS-UMII-ENSCM, Bagnols sur Ceze Cedex (France); Colle, Jean-Yves [Institute for Transuranium Elements, Joint Research Centre, European Commission, P.O. Box 2340, 76125 Karlsruhe (Germany); Iosilevskiy, Igor [Joint Institute for High Temperature, Russian Academy of Science, 125412 Moscow (Russian Federation); Moscow Institute of Physics and Technology, State University, 141700 Moscow (Russian Federation); Extreme Matter Institute (EMMI), 64291 Darmstadt (Germany); Sheindlin, Michael [Institute for Transuranium Elements, Joint Research Centre, European Commission, P.O. Box 2340, 76125 Karlsruhe (Germany); Joint Institute for High Temperature, Russian Academy of Science, 125412 Moscow (Russian Federation)

2011-02-01T23:59:59.000Z

125

Development of a polysilicon process based on chemical vapor deposition. Phase 1. Fourth quarterly progress report, 1 July-30 September 1980  

DOE Green Energy (OSTI)

The goal of this program is to demonstrate that a dichlorosilane-based reductive chemical vapor deposition (CVD) process is capable of producing, at low cost, high quality polycrystalline silicon for use in the manufacture of high efficiency solar cells. The feasibility of silicon generation from dichlorosilane (DCS) has been well established. The feasibility and optimization portions of the experimental reactor program have been completed, with a number of runs having been conducted over a broad range of conditions in an experimental CVD reactor. Activities relating to feed of commercially purchased DCS to an intermediate sized reactor and to construction of a Process Development Unit (PDU) to generate and feed DCS to one or more production scale reactors were suspended during the previous quarter because of the receipt of new safety-related information about DCS from Hazards Research Corp. Experimental data generated by Hazards Research Corp. indicate that DCS/air mixtures possess about four times the explosive severity potential as hydrogen/air mixtures, and that DCS/air mixtures are very readily ignited. As a consequence of this new information, designs and procedures for the intermediate reactor feed and PDU tasks were deemed inadequate and new designs incorporating new safety-related elements are being formulated. A preliminary economic evaluation of the Hemlock Semiconductor process has been completed. The analysis for a plant to generate 1000 metric tonne of silicon indicates a plant investment of $21.9 M, and a product selling price of $19.85/kg.

Sharp, K.; Arvidson, A.; Sawyer, D.

1980-12-01T23:59:59.000Z

126

Development of a polysilicon process based on chemical vapor deposition (Phase 1). First quarterly progress report, 6 October-31 December 1979  

DOE Green Energy (OSTI)

The goal of this program is to demonstrate that a dichlorosilane based reductive chemical vapor deposition (CVD) process is capable of producing, at low cost, high quality polycrystalline silicon. Physical form and purity of this material will be consistent with LSA material requirements for use in the manufacture of high efficiency solar cells. Chemical processes involved in achieving the objective are reviewed with emphasis placed on advantages of this process when compared with existing polycrystalline silicon production technology. Installation of a CVD reactor with associated analytical instrumentation is described. Preliminary reactor data has been favorable demonstrating the anticipated increased deposition rate and conversion efficiency when dichlorosilane decomposition is compared with trichlorosilane decomposition. No serious problems have been encountered which might limit dichlorosilane use as a reactor feed material. Design considerations for a process development unit (PDU) for dichlorosilane synthesis are reviewed. A design which effectively suppresses monochlorosilane during the redistribution of trichlorosilane was decided upon and its implementation is described. The PDU will be used to collect data on optimization of the redistribution process as well as to determine product quality. Based on experimental data collected during the first quarter along with already available data on the redistribution and hydrogenation processes, a preliminary mass balance is established.

McCormick, J. R.; Arvidson, A.; Plahutnik, F.; Sawyer, D.; Sharp, K.

1980-01-01T23:59:59.000Z

127

Chemical Hydride Slurry for Hydrogen Production and Storage  

Science Conference Proceedings (OSTI)

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

McClaine, Andrew W.

2008-09-30T23:59:59.000Z

128

The Hydriding Kinetics of Organic Hydrogen Getters  

DOE Green Energy (OSTI)

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

Powell, G. L.

2002-02-11T23:59:59.000Z

129

Vapor spill monitoring method  

DOE Patents (OSTI)

Method for continuous sampling of liquified natural gas effluent from a spill pipe, vaporizing the cold liquified natural gas, and feeding the vaporized gas into an infrared detector to measure the gas composition. The apparatus utilizes a probe having an inner channel for receiving samples of liquified natural gas and a surrounding water jacket through which warm water is flowed to flash vaporize the liquified natural gas.

Bianchini, Gregory M. (Livermore, CA); McRae, Thomas G. (Livermore, CA)

1985-01-01T23:59:59.000Z

130

Hydrogen storage in sodium aluminum hydride.  

DOE Green Energy (OSTI)

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

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

2005-11-01T23:59:59.000Z

131

Steps to Commercialization: Nickel Metal Hydride Batteries | Department of  

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

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

132

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

DOE Patents (OSTI)

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

Crisler, L.R.

1975-11-11T23:59:59.000Z

133

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

134

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

Science Conference Proceedings (OSTI)

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

135

Development of the Low-Pressure Hydride/Dehydride Process  

DOE Green Energy (OSTI)

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

Rueben L. Gutierrez

2001-04-01T23:59:59.000Z

136

Distributions of Liquid, Vapor, and Ice in an Orographic Cloud from Field Observations  

Science Conference Proceedings (OSTI)

The phase distribution of the water mass of a cold orographic cloud into vapor, liquid, and ice is calculated from measurements made from an instrumented aircraft. The vapor values are calculated from thermodynamic measurements, and the liquid is ...

Taneil Uttal; Robert M. Rauber; Lewis O. Grant

1988-04-01T23:59:59.000Z

137

Aerogel composites using chemical vapor infiltration  

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

Aerogel composites using chemical vapor infiltration Aerogel composites using chemical vapor infiltration Title Aerogel composites using chemical vapor infiltration Publication Type Journal Article Year of Publication 1995 Authors Hunt, Arlon J., Michael R. Ayers, and Wanqing Cao Journal Journal of Non-Crystalline Solids Volume 185 Pagination 227-232 Abstract A new method to produce novel composite materials based on the use of aerogels as a starting material is described. Using chemical vapor infiltration, a variety of solid materials were thermally deposited into the open pore structure of aerogel. The resulting materials possess new and unusual properties including photoluminescence, magnetism and altered optical properties. An important characteristic of this preparation process is the very small size of the deposits that gives rise to new behaviors. Silicon deposits exhibit photoluminescence, indicating quantum confinement. Two or more phases may be deposited simultaneously and one or both chemically or thermally reacted to produce new structures.

138

Optimization of Hydride Rim Formation in Unirradiated Zr 4 Cladding  

Science Conference Proceedings (OSTI)

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

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

2013-09-30T23:59:59.000Z

139

Electronic structure, bonding and chemisorption in metallic hydrides  

DOE Green Energy (OSTI)

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

Ward, J.W.

1980-01-01T23:59:59.000Z

140

Chemical vapor deposition sciences  

SciTech Connect

Chemical vapor deposition (CVD) is a widely used method for depositing thin films of a variety of materials. Applications of CVD range from the fabrication of microelectronic devices to the deposition of protective coatings. New CVD processes are increasingly complex, with stringent requirements that make it more difficult to commercialize them in a timely fashion. However, a clear understanding of the fundamental science underlying a CVD process, as expressed through computer models, can substantially shorten the time required for reactor and process development. Research scientists at Sandia use a wide range of experimental and theoretical techniques for investigating the science of CVD. Experimental tools include optical probes for gas-phase and surface processes, a range of surface analytic techniques, molecular beam methods for gas/surface kinetics, flow visualization techniques and state-of-the-art crystal growth reactors. The theoretical strategy uses a structured approach to describe the coupled gas-phase and gas-surface chemistry, fluid dynamics, heat and mass transfer of a CVD process. The software used to describe chemical reaction mechanisms is easily adapted to codes that model a variety of reactor geometries. Carefully chosen experiments provide critical information on the chemical species, gas temperatures and flows that are necessary for model development and validation. This brochure provides basic information on Sandia`s capabilities in the physical and chemical sciences of CVD and related materials processing technologies. It contains a brief description of the major scientific and technical capabilities of the CVD staff and facilities, and a brief discussion of the approach that the staff uses to advance the scientific understanding of CVD processes.

1992-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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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141

Vaporization of synthetic fuels. Final report. [Thesis  

DOE Green Energy (OSTI)

The problem of transient droplet vaporization in a hot convective environment is examined. The main objective of the present study is to develop an algorithm for the droplet vaporization which is simple enough to be feasibly incorporated into a complete spray combustion analysis and yet will also account for the important physics such as liquid-phase internal circulation, unsteady droplet heating and axisymmetric gas-phase convection. A simplified liquid-phase model has been obtained based on the assumption of the existence of a Hill's spherical vortex inside the droplet together with some approximations made in the governing diffusion equation. The use of the simplified model in a spray situation has also been examined. It has been found that droplet heating and vaporization are essentially unsteady and droplet temperature is nonuniform for a significant portion of its lifetime. It has also been found that the droplet vaporization characteristic can be quite sensitive to the particular liquid-phase and gas-phase models. The results of the various models are compared with the existing experimental data. Due to large scattering in the experimental measurements, particularly the droplet diameter, no definite conclusion can be drawn based on the experimental data. Finally, certain research problems which are related to the present study are suggested for future studies.

Sirignano, W.A.; Yao, S.C.; Tong, A.Y.; Talley, D.

1983-01-01T23:59:59.000Z

142

System for exchange of hydrogen between liquid and solid phases  

DOE Patents (OSTI)

The reversible reaction M + x/2 H/sub 2/ reversible MH/sub x/, wherein M is a reversible 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 an inert liquid, thereby reducing contamination, providing better temperature control, providing in situ mobility of the reactants, and increasing flexibility in process design. Thus, a slurry of particles of a metal hydride former with an inert solvent is subjected to a temperature and pressure controlled atmosphere containing H/sub 2/, to store hydrogen and to release 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 actual H/sub 2/ pressure 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 actual 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.; Johnson, J.R.; Winsche, W.E.

1985-02-22T23:59:59.000Z

143

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

Science Conference Proceedings (OSTI)

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

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

2012-01-01T23:59:59.000Z

144

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

E-Print Network (OSTI)

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

Figueroa, Joshua S

2005-01-01T23:59:59.000Z

145

ALUMINUM HYDRIDE, A1H3, AS A HYDROGEN STORAGE COMPOUND.  

DOE Green Energy (OSTI)

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

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

2006-11-27T23:59:59.000Z

146

Heat transfer during film condensation of potassium vapor  

E-Print Network (OSTI)

The object of this work is to investigate theoretically and experimentally the following two phases of heat transfer during condensation of potassium vapore, a. Heat transfer during film condensation of pure saturated ...

Kroger, Detlev Gustav

1966-01-01T23:59:59.000Z

147

Final Report for the DOE Metal Hydride Center of Excellence  

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

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

148

A REVIEW OF THE RARE-EARTH HYDRIDES  

SciTech Connect

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

Mulford, R.N.R.

1950-01-01T23:59:59.000Z

149

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

150

Heat-actuated metal hydride hydrogen compressor testing  

SciTech Connect

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

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

1985-09-01T23:59:59.000Z

151

Effects of capillarity and vapor adsorption in the depletion of vapor-dominated geothermal reservoirs  

DOE Green Energy (OSTI)

Vapor-dominated geothermal reservoirs in natural (undisturbed) conditions contain water as both vapor and liquid phases. The most compelling evidence for the presence of distributed liquid water is the observation that vapor pressures in these systems are close to saturated vapor pressure for measured reservoir temperatures (White et al., 1971; Truesdell and White, 1973). Analysis of natural heat flow conditions provides additional, indirect evidence for the ubiquitous presence of liquid. From an analysis of the heat pipe process (vapor-liquid counterflow) Preuss (1985) inferred that effective vertical permeability to liquid phase in vapor-dominated reservoirs is approximately 10{sup 17} m{sup 2}, for a heat flux of 1 W/m{sup 2}. This value appears to be at the high end of matrix permeabilities of unfractured rocks at The Geysers, suggesting that at least the smaller fractures contribute to liquid permeability. For liquid to be mobile in fractures, the rock matrix must be essentially completely liquid-saturated, because otherwise liquid phase would be sucked from the fractures into the matrix by capillary force. Large water saturation in the matrix, well above the irreducible saturation of perhaps 30%, has been shown to be compatible with production of superheated steam (Pruess and Narasimhan, 1982). In response to fluid production the liquid phase will boil, with heat of vaporization supplied by the reservoir rocks. As reservoir temperatures decline reservoir pressures will decline also. For depletion of ''bulk'' liquid, the pressure would decline along the saturated vapor pressure curve, while for liquid held by capillary and adsorptive forces inside porous media, an additional decline will arise from ''vapor pressure lowering''. Capillary pressure and vapor adsorption effects, and associated vapor pressure lowering phenomena, have received considerable attention in the geothermal literature, and also in studies related to geologic disposal of heat generating nuclear wastes, and in the drying of porous materials. Geothermally oriented studies were presented by Chicoine et al. (1977), Hsieh and Ramey (1978, 1981), Herkelrath et al. (1983), and Nghiem and Ramey (1991). Nuclear waste-related work includes papers by Herkelrath and O'Neal (1985), Pollock (1986), Eaton and Bixler (1987), Pruess et al. (1990), Nitao (1990), and Doughty and E'ruess (1991). Applications to industrial drying of porous materials have been discussed by Hamiathy (1969) arid Whitaker (1977). This paper is primarily concerned with evaluating the impact of vapor pressure lowering (VPL) effects on the depletion behavior of vapor-dominated reservoirs. We have examined experimental data on vapor adsorption and capillary pressures in an effort to identify constitutive relationships that would be applicable to the tight matrix rocks of vapor-dominated systems. Numerical simulations have been performed to evaluate the impact of these effects on the depletion of vapor-dominated reservoirs.

Pruess, Karsten; O'Sullivan, Michael

1992-01-01T23:59:59.000Z

152

High-Spin Cobalt Hydrides for Catalysis  

SciTech Connect

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

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

2013-08-29T23:59:59.000Z

153

METHOD OF PREPARING SINTERED ZIRCONIUM METAL FROM ITS HYDRIDES  

DOE Patents (OSTI)

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

Angier, R.P.

1958-02-11T23:59:59.000Z

154

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

SciTech Connect

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

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

2013-01-01T23:59:59.000Z

155

Low temperature metal-organic chemical vapor deposition growth processes for high-efficiency solar cells. Final technical report, 1 September 1985--30 November 1989  

DOE Green Energy (OSTI)

This report describes the results of a program to develop a more complete understanding of the physical and chemical processes involved in low-temperature growth of III-V compounds by metal-organic chemical vapor deposition (MOCVD) and to develop a low-temperature process that is suitable for the growth of high-efficiency solar cells. The program was structured to develop a better understanding of the chemical reactions involved in MOCVD growth, to develop a model of the processes occurring in the gas phase, to understand the physical kinetics and reactions operative on the surface of the growing crystal, and to develop an understanding of the means by which these processes may be altered to reduce the temperature of growth and the utilization of toxic hydrides. The basic approach was to develop the required information about the chemical and physical kinetics operative in the gas phase and on the surface by the direct physical measurement of the processes whenever possible. The program included five tasks: (1) MOCVD growth process characterization, (2) photoenhanced MOCVD studies, (3) materials characterization, (4) device fabrication and characterization, and (5) photovoltaic training. Most of the goals of the program were met and significant progress was made in defining an approach that would allow both high throughput and high uniformity growth of compound semiconductors at low temperatures. The technical activity was focused on determining the rates of thermal decomposition of trimethyl gallium, exploring alternate arsenic sources for use MOCVD, and empirical studies of atomic layer epitaxy as an approach.

Dapkus, P.D. [University of Southern California, Los Angeles, CA (United States)

1993-02-01T23:59:59.000Z

156

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

Science Conference Proceedings (OSTI)

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

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

2013-09-01T23:59:59.000Z

157

Organometallic Vapor Phase Epitaxy Technical Program  

Science Conference Proceedings (OSTI)

Mar 12, 2001 ... integrity, Emergency Response, Safety for the ESG products. The pre- ... systems, multi-point gas monitoring, and one or more emergency gas.

158

Experimental and Modeling Study of the Flammability of Fuel Tank Headspace Vapors from Ethanol/Gasoline Fuels; Phase 3: Effects of Winter Gasoline Volatility and Ethanol Content on Blend Flammability; Flammability Limits of Denatured Ethanol  

DOE Green Energy (OSTI)

This study assessed differences in headspace flammability for summertime gasolines and new high-ethanol content fuel blends. The results apply to vehicle fuel tanks and underground storage tanks. Ambient temperature and fuel formulation effects on headspace vapor flammability of ethanol/gasoline blends were evaluated. Depending on the degree of tank filling, fuel type, and ambient temperature, fuel vapors in a tank can be flammable or non-flammable. Pure gasoline vapors in tanks generally are too rich to be flammable unless ambient temperatures are extremely low. High percentages of ethanol blended with gasoline can be less volatile than pure gasoline and can produce flammable headspace vapors at common ambient temperatures. The study supports refinements of fuel ethanol volatility specifications and shows potential consequences of using noncompliant fuels. E85 is flammable at low temperatures; denatured ethanol is flammable at warmer temperatures. If both are stored at the same location, one or both of the tanks' headspace vapors will be flammable over a wide range of ambient temperatures. This is relevant to allowing consumers to splash -blend ethanol and gasoline at fueling stations. Fuels compliant with ASTM volatility specifications are relatively safe, but the E85 samples tested indicate that some ethanol fuels may produce flammable vapors.

Gardiner, D. P.; Bardon, M. F.; Clark, W.

2011-07-01T23:59:59.000Z

159

Electrolyte vapor condenser  

DOE Patents (OSTI)

A system is disclosed for removing electrolyte from a fuel cell gas stream. The gas stream containing electrolyte vapor is supercooled utilizing conventional heat exchangers and the thus supercooled gas stream is passed over high surface area passive condensers. The condensed electrolyte is then drained from the condenser and the remainder of the gas stream passed on. The system is particularly useful for electrolytes such as phosphoric acid and molten carbonate, but can be used for other electrolyte cells and simple vapor separation as well. 3 figs.

Sederquist, R.A.; Szydlowski, D.F.; Sawyer, R.D.

1983-02-08T23:59:59.000Z

160

Electrolyte vapor condenser  

DOE Patents (OSTI)

A system is disclosed for removing electrolyte from a fuel cell gas stream. The gas stream containing electrolyte vapor is supercooled utilizing conventional heat exchangers and the thus supercooled gas stream is passed over high surface area passive condensers. The condensed electrolyte is then drained from the condenser and the remainder of the gas stream passed on. The system is particularly useful for electrolytes such as phosphoric acid and molten carbonate, but can be used for other electrolyte cells and simple vapor separation as well.

Sederquist, Richard A. (Newington, CT); Szydlowski, Donald F. (East Hartford, CT); Sawyer, Richard D. (Canton, CT)

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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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161

Vapor concentration monitor  

DOE Patents (OSTI)

An apparatus for monitoring the concentration of a vapor, such as heavy water, having at least one narrow bandwidth in its absorption spectrum, in a sample gas such as air. The air is drawn into a chamber in which the vapor content is measured by means of its radiation absorption spectrum. High sensitivity is obtained by modulating the wavelength at a relatively high frequency without changing its optical path, while high stability against zero drift is obtained by the low frequency interchange of the sample gas to be monitored and of a reference sample. The variable HDO background due to natural humidity is automatically corrected.

Bayly, John G. (Deep River, CA); Booth, Ronald J. (Deep River, CA)

1977-01-01T23:59:59.000Z

162

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

DOE Green Energy (OSTI)

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

Damle, A.

2010-02-03T23:59:59.000Z

163

Definition: Mercury Vapor | Open Energy Information  

Open Energy Info (EERE)

Mercury Vapor Jump to: navigation, search Dictionary.png Mercury Vapor Mercury is discharged as a highly volatile vapor during hydrothermal activity and high concentrations in...

164

Organic vapor jet printing system  

DOE Patents (OSTI)

An organic vapor jet printing system includes a pump for increasing the pressure of an organic flux.

Forrest, Stephen R

2012-10-23T23:59:59.000Z

165

Mercury Vapor | Open Energy Information  

Open Energy Info (EERE)

Mercury Vapor Mercury Vapor Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Mercury Vapor Details Activities (23) Areas (23) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Fluid Lab Analysis Parent Exploration Technique: Fluid Lab Analysis Information Provided by Technique Lithology: Stratigraphic/Structural: Anomalously high concentrations can indicate high permeability or conduit for fluid flow Hydrological: Field wide soil sampling can generate a geometrical approximation of fluid circulation Thermal: High concentration in soils can be indicative of active hydrothermal activity Dictionary.png Mercury Vapor: Mercury is discharged as a highly volatile vapor during hydrothermal

166

Fuel vapor canister  

SciTech Connect

This paper discusses an improved fuel vapor storage canister for use in a vehicle emission system of the type utilizing an enclosure with an interior communicated with a source of fuel vapor. The improved canister comprises: the enclosure having a mixture including particles of activated charcoal and many pieces of foam rubber, the pieces of foam rubber in the mixture being randomly and substantially evenly dispersed whereby substantially all the charcoal particles are spaced relatively closely to at least one foam rubber piece; the mixture being packed into the enclosure under pressure so that the pieces of foam rubber are compressed enough to tightly secure the charcoal particles one against another to prevent a griding action therebetween.

Moskaitis, R.J.; Ciuffetelli, L.A.

1991-03-26T23:59:59.000Z

167

Stratified vapor generator  

DOE Patents (OSTI)

A stratified vapor generator (110) comprises a first heating section (H.sub.1) and a second heating section (H.sub.2). The first and second heating sections (H.sub.1, H.sub.2) are arranged so that the inlet of the second heating section (H.sub.2) is operatively associated with the outlet of the first heating section (H.sub.1). A moisture separator (126) having a vapor outlet (164) and a liquid outlet (144) is operatively associated with the outlet (124) of the second heating section (H.sub.2). A cooling section (C.sub.1) is operatively associated with the liquid outlet (144) of the moisture separator (126) and includes an outlet that is operatively associated with the inlet of the second heating section (H.sub.2).

Bharathan, Desikan (Lakewood, CO); Hassani, Vahab (Golden, CO)

2008-05-20T23:59:59.000Z

168

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

Science Conference Proceedings (OSTI)

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

Greenspan, Ehud; Todreas, Neil; Taiwo, Temitope

2009-03-10T23:59:59.000Z

169

Composition and function in AB{sub 5} hydride electrodes  

DOE Green Energy (OSTI)

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

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

1996-12-31T23:59:59.000Z

170

ALUMINUM HYDRIDE: A REVERSIBLE STORAGE MATERIAL FOR HYDROGEN STORAGE  

DOE Green Energy (OSTI)

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

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

2009-01-09T23:59:59.000Z

171

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

SciTech Connect

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

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

1988-08-01T23:59:59.000Z

172

VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS  

DOE Green Energy (OSTI)

This project had as its main focus the determination of vapor pressures of coal pyrolysis tars. It involved performing measurements of these vapor pressures and from them, developing vapor pressure correlations suitable for use in advanced pyrolysis models (those models which explicitly account for mass transport limitations). This report is divided into five main chapters. Each chapter is a relatively stand-alone section. Chapter A reviews the general nature of coal tars and gives a summary of existing vapor pressure correlations for coal tars and model compounds. Chapter B summarizes the main experimental approaches for coal tar preparation and characterization which have been used throughout the project. Chapter C is concerned with the selection of the model compounds for coal pyrolysis tars and reviews the data available to us on the vapor pressures of high boiling point aromatic compounds. This chapter also deals with the question of identifying factors that govern the vapor pressures of coal tar model materials and their mixtures. Chapter D covers the vapor pressures and heats of vaporization of primary cellulose tars. Chapter E discusses the results of the main focus of this study. In summary, this work provides improved understanding of the volatility of coal and cellulose pyrolysis tars. It has resulted in new experimentally verified vapor pressure correlations for use in pyrolysis models. Further research on this topic should aim at developing general vapor pressure correlations for all coal tars, based on their molecular weight together with certain specific chemical characteristics i.e. hydroxyl group content.

Eric M. Suuberg; Vahur Oja

1997-07-01T23:59:59.000Z

173

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

E-Print Network (OSTI)

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

Kim, Ki Chul

2010-01-01T23:59:59.000Z

174

Electrochromically switched, gas-reservoir metal hydride devices with  

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

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

175

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

DOE Green Energy (OSTI)

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

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

1994-05-01T23:59:59.000Z

176

New High Performance Water Vapor Membranes to Improve Fuel Cell Balance of Plant Efficiency and Lower Costs (SBIR Phase I) - DOE Hydrogen and Fuel Cells Program FY 2012 Annual Progress Report  

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

0 0 DOE Hydrogen and Fuel Cells Program FY 2012 Annual Progress Report Earl H. Wagener (Primary Contact), Brad P. Morgan, Jeffrey R. DiMaio Tetramer Technologies L.L.C. 657 S. Mechanic St. Pendleton, SC 29670 Phone: (864) 646-6282 Email: earl.wagener@tetramertechnologies.com DOE Manager HQ: Nancy Garland Phone: (202) 586-5673 Email: Nancy.Garland@ee.doe.gov Contract Number: DE-SC0006172 Project Start Date: June 17, 2011 Project End Date: March 16, 2012 Fiscal Year (FY) 2012 Objectives Demonstrate water vapor transport membrane with * >18,000 gas permeation units (GPU) Water vapor membrane with less than 20% loss in * performance after stress tests Crossover leak rate: <150 GPU * Temperature Durability of 90°C with excursions to * 100°C Cost of <$10/m

177

Vapor spill pipe monitor  

DOE Patents (OSTI)

The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote ir gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote ir sensor which measures the gas composition.

Bianchini, G.M.; McRae, T.G.

1983-06-23T23:59:59.000Z

178

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

DOE Green Energy (OSTI)

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

Feraday, M.A.

1971-11-15T23:59:59.000Z

179

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

DOE Green Energy (OSTI)

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

Ting, J.

1999-02-12T23:59:59.000Z

180

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

E-Print Network (OSTI)

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

Parkison, Adam Joseph

2008-05-01T23:59:59.000Z

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


181

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

E-Print Network (OSTI)

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

Victoria, University of

182

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

183

Analytical and numerical models of uranium ignition assisted by hydride formation  

DOE Green Energy (OSTI)

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

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

1996-05-01T23:59:59.000Z

184

HYDRIDES AND METAL-HYDROGEN SYSTEMS. Final Report  

DOE Green Energy (OSTI)

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

Gibb, T.R.P. Jr.

1951-04-30T23:59:59.000Z

185

ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE  

DOE Green Energy (OSTI)

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

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

2009-01-09T23:59:59.000Z

186

ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE  

DOE Green Energy (OSTI)

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

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

2008-12-31T23:59:59.000Z

187

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

Office of Legacy Management (LM)

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

188

Sintering of sponge and hydride-dehydride titanium powders  

Science Conference Proceedings (OSTI)

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

Alman, David E.; Gerdemann, Stephen J.

2004-04-01T23:59:59.000Z

189

Metal hydride based isotope separation: Large-scale operations  

DOE Green Energy (OSTI)

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

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

1991-01-01T23:59:59.000Z

190

Metal hydride based isotope separation: Large-scale operations  

DOE Green Energy (OSTI)

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

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

1991-12-31T23:59:59.000Z

191

Chemical Hydrides for Hydrogen Storage in Fuel Cell Applications  

Science Conference Proceedings (OSTI)

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

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

2012-04-16T23:59:59.000Z

192

Electrochemical process and production of novel complex hydrides  

SciTech Connect

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

Zidan, Ragaiy

2013-06-25T23:59:59.000Z

193

Interfacial instability induced by lateral vapor pressure fluctuation in bounded thin liquid-vapor layers  

E-Print Network (OSTI)

We study an instability of thin liquid-vapor layers bounded by rigid parallel walls from both below and above. In this system, the interfacial instability is induced by lateral vapor pressure fluctuation, which is in turn attributed to the effect of phase change: evaporation occurs at the hotter portion of the interface and condensation at the colder one. The high vapor pressure drives the liquid away and the low one pulls it up. A set of equations describing the temporal evolution of the interface of the liquid-vapor layers is derived. This model neglects the effect of mass loss or gain at the interface and guarantees the mass conservation of the liquid layer. The result of linear stability analysis of the model shows that the presence of the pressure dependence of the local saturation temperature suppresses the growth of long-wave disturbances. We find the stability criterion, which suggests that only slight temperature gradients are sufficient to overcome the stabilizing gravitational effect for a water an...

Kanatani, Kentaro

2008-01-01T23:59:59.000Z

194

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

Science Conference Proceedings (OSTI)

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

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

2002-01-01T23:59:59.000Z

195

ACCEPTABILITY ENVELOPE FOR METAL HYDRIDE-BASED HYDROGEN STORAGE SYSTEMS  

DOE Green Energy (OSTI)

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

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

2011-07-18T23:59:59.000Z

196

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

197

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

Science Conference Proceedings (OSTI)

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

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

2011-02-14T23:59:59.000Z

198

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

SciTech Connect

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

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

2011-02-14T23:59:59.000Z

199

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

DOE Green Energy (OSTI)

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

Stout, R.B.

1989-10-01T23:59:59.000Z

200

VAPOR SHIELD FOR INDUCTION FURNACE  

DOE Patents (OSTI)

This patent relates to a water-cooled vapor shield for an inductlon furnace that will condense metallic vapors arising from the crucible and thus prevent their condensation on or near the induction coils, thereby eliminating possible corrosion or shorting out of the coils. This is accomplished by placing, about the top, of the crucible a disk, apron, and cooling jacket that separates the area of the coils from the interior of the cruclbIe and provides a cooled surface upon whlch the vapors may condense.

Reese, S.L.; Samoriga, S.A.

1958-03-11T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

Vapor-Liquid Partitioning of Sulfuric Acid and Ammonium Sulfate  

Science Conference Proceedings (OSTI)

The quality of water and steam is central to ensuring power plant component availability and reliability. A key part of developing operating cycle chemistry guidelines is an understanding of the impurity distribution between water and steam. This study focused on the partitioning of sulfuric acid and ammonium bisulfate between the liquid and vapor phases.

1999-03-31T23:59:59.000Z

202

Vapor adsorption process  

SciTech Connect

The removal of undesirable acid components from sour natural gas is often accomplished by a vapor adsorption process wherein a bed of solid adsorbent material is contacted with an inlet gas stream so that desired components contained in the gas stream are adsorbed on the bed, then regenerated by contact with a heated regeneration gas stream. Adsorbed components are desorbed from the bed and the bed is cooled preparatory to again being contacted with the inlet gas stream. By this process, the bed is contacted, during the regeneration cycle, with a selected adsorbable material. This material has the property of being displaced from the bed by the desired components and has a heat of desorption equal to or greater than the heat of adsorption of the desired components. When the bed is contacted with the inlet gas stream, the selected adsorbable material is displaced by the desired components resulting in the temperature of the bed remaining relatively constant, thereby allowing the utilization of the maximum bed adsorption capacity. (4 claims)

Snyder, C.F.; Casad, B.M.

1973-04-24T23:59:59.000Z

203

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

DOE Green Energy (OSTI)

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

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

1960-03-10T23:59:59.000Z

204

Atmospheric Water Vapor over China  

Science Conference Proceedings (OSTI)

Chinese radiosonde data from 1970 to 1990 are relatively homogeneous in time and are used to examine the climatology, trends, and variability of Chinas atmospheric water vapor content. The climatological distribution of precipitable water (PW) ...

Panmao Zhai; Robert E. Eskridge

1997-10-01T23:59:59.000Z

205

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

DOE Green Energy (OSTI)

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

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

2004-02-23T23:59:59.000Z

206

Vapor deposition of hardened niobium  

DOE Patents (OSTI)

A method of coating ceramic nuclear fuel particles containing a major amount of an actinide ceramic in which the particles are placed in a fluidized bed maintained at ca. 800.degree. to ca. 900.degree. C., and niobium pentachloride vapor and carbon tetrachloride vapor are led into the bed, whereby niobium metal is deposited on the particles and carbon is deposited interstitially within the niobium. Coating apparatus used in the method is also disclosed.

Blocher, Jr., John M. (Columbus, OH); Veigel, Neil D. (Columbus, OH); Landrigan, Richard B. (Columbus, OH)

1983-04-19T23:59:59.000Z

207

Final report for the DOE Metal Hydride Center of Excellence.  

DOE Green Energy (OSTI)

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

Keller, Jay O.; Klebanoff, Leonard E.

2012-01-01T23:59:59.000Z

208

Wall pressure exerted by hydrogenation of sodium aluminum hydride.  

DOE Green Energy (OSTI)

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

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

2009-06-01T23:59:59.000Z

209

Nickel-metal hydride battery development. Final technical report  

SciTech Connect

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

1995-06-01T23:59:59.000Z

210

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

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

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

211

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

SciTech Connect

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

Nasise, J.E.

1988-09-01T23:59:59.000Z

212

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

SciTech Connect

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

Nasise, J.E.

1988-01-01T23:59:59.000Z

213

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

DOE Green Energy (OSTI)

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

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

1979-10-01T23:59:59.000Z

214

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

E-Print Network (OSTI)

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

215

Photogeneration of Hydride Donors and Their Use Toward CO2 Reduction  

DOE Green Energy (OSTI)

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

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

2009-06-07T23:59:59.000Z

216

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

Science Conference Proceedings (OSTI)

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

None

2011-12-01T23:59:59.000Z

217

Ethanol production by vapor compression distillation  

DOE Green Energy (OSTI)

The goal of this project is to develop and demonstrate a one gallon per hour vapor compression distillation unit for fuel ethanol production that can be profitably manufactured and economically operated by individual family units. Vapor compression distillation is already an industrially accepted process and this project's goal is to demonstrate that it can be done economically on a small scale. Theoretically, the process is independent of absolute pressure. It is only necessary that the condenser be at higher pressure than the evaporator. By reducing the entire process to a pressure of approximately 0.1 atmosphere, the evaporation and condensation can occur at near ambient temperature. Even though this approach requires a vacuum pump, and thus will not represent the final cost effective design, it does not require preheaters, high temperature materials, or as much insulation as if it were to operate a near ambient pressure. Therefore, the operation of the ambient temperature unit constitutes the first phase of this project. Presently, the ambient temperature unit is fully assembled and has begun testing. So far it has successfully separated ethanol from a nine to one diluted input solution. However the production rate has been very low.

Ellis, G.S.

1981-01-01T23:59:59.000Z

218

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

Science Conference Proceedings (OSTI)

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

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

1986-04-01T23:59:59.000Z

219

Synthesis and characterization of metal hydride electrodes. Interim report  

DOE Green Energy (OSTI)

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

McBreen, J.; Reilly, J.J.

1995-10-01T23:59:59.000Z

220

How solvent vapors can improve steam floods  

Science Conference Proceedings (OSTI)

Thermal recovery methods depend for their success on the viscosity reduction of heavy crude oils at high temperatures. The viscosity of a heavy oil can also be reduced if it is diluted with a low-viscosity solvent, such as one of the lighter hydrocarbons. It is not surprising that there has been considerable interest in combining the two methods. The process of injecting vaporized solvent with the steam for a gravity drainage type recovery is described here along with a description of the particular phase behavior of steam/solvent mixtures which is beneficial to the process. And computer simulations which compare steam-only and steam/solvent floods under Athabasca-type conditions are overviewed.

Vogel, J. [Vogel, (Jack), Seabrook, TX (United States)

1996-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

Atomic vapor laser isotope separation process  

DOE Patents (OSTI)

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

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

1990-08-21T23:59:59.000Z

222

Vapor Pressure Measurement of Supercooled Water  

Science Conference Proceedings (OSTI)

A new dewpoint hygrometer was developed for subfreezing temperature application. Vapor pressure of supercooled water was determined by measuring temperatures at the dew-forming surface and the vapor source ice under the flux density balance, and ...

N. Fukuta; C. M. Gramada

2003-08-01T23:59:59.000Z

223

Distribution of Tropical Tropospheric Water Vapor  

Science Conference Proceedings (OSTI)

Utilizing a conceptual model for tropical convection and observational data for water vapor, the maintenance of the vertical distribution of the tropical tropospheric water vapor is discussed. While deep convection induces large-scale subsidence ...

De-Zheng Sun; Richard S. Lindzen

1993-06-01T23:59:59.000Z

224

Atmospheric Water Vapor Characteristics at 70N  

Science Conference Proceedings (OSTI)

Using an extensive rawinsonde archive, characteristics of Arctic water vapor and its transports at 70N are examined for the period 19741991. Monthly-mean profiles and vertically integrated values of specific humidity and meridional vapor fluxes ...

Mark C. Serreze; Roger G. Barry; John E. Walsh

1995-04-01T23:59:59.000Z

225

Alternatives for metal hydride storage bed heating and cooling  

DOE Green Energy (OSTI)

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

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

1991-10-04T23:59:59.000Z

226

On-board hydrogen storage system using metal hydride  

DOE Green Energy (OSTI)

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

Heung, L.K.

1997-07-01T23:59:59.000Z

227

LOW PRESSURE CHEMICAL VAPOR DEPOSITION OF POLYSILICON  

E-Print Network (OSTI)

THEORY The mass transport processes in low pressure chemical vapor deposition (LPCVD) are similar to those occuring in catalytic reactors

Gieske, R.J.

2011-01-01T23:59:59.000Z

228

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

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

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

229

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

DOE Green Energy (OSTI)

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

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

1979-04-01T23:59:59.000Z

230

Vapor Pressures and Heats of Vaporization of Primary Coal Tars  

Office of Scientific and Technical Information (OSTI)

/ PC92544-18 / PC92544-18 VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS FINAL REPORT Grant Dates: August, 1992 - November, 1996 Principal Authors: Eric M. Suuberg (PI) and Vahur Oja Report Submitted: April, 1997 Revised: July, 1997 Grant Number: DE-FG22-92PC92544 Report Submitted by: ERIC M. SUUBERG DIVISION OF ENGINEERING BROWN UNIVERSITY PROVIDENCE, RI 02912 TEL. (401) 863-1420 Prepared For: U. S. DEPT. OF ENERGY FEDERAL ENERGY TECHNOLOGY CENTER P.O. BOX 10940 PITTSBURGH, PA 15236 DR. KAMALENDU DAS, FETC, MORGANTOWN , WV TECHNICAL PROJECT OFFICER "US/DOE Patent Clearance is not required prior to the publication of this document" ii United States Government Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any

231

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.

232

Phase Field Simulations  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... The anisotropic solid-vapor surface energy for a 2D PFC hexagonal crystal is ... Finally, we examine the dynamic case of step-flow growth of a crystal into ... Thermal and Dispersed-Phase Analysis of Nano Fluid Using CFD-A Hybrid ... gas turbine power generation systems because of its high melting point,...

233

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

DOE Green Energy (OSTI)

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

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

2011-03-28T23:59:59.000Z

234

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

DOE Green Energy (OSTI)

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

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

2012-01-01T23:59:59.000Z

235

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

DOE Green Energy (OSTI)

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

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

2007-07-27T23:59:59.000Z

236

The origin of high-temperature zones in vapor-dominated geothermal systems  

DOE Green Energy (OSTI)

Vapor-dominated geothermal systems are proposed to originate by downward extension (by the ''heat pipe'' mechanism) into hot dry fractured rock above a large cooling igneous intrusion. High temperature zones found by drilling are shallow parts of the original hot dry rock where the penetration of the vapor reservoir was limited, and hot dry rock may extend under much of these reservoirs. An earlier hot water geothermal system may have formed during an early phase of the heating episode.

Truesdell, Alfred H.

1991-01-01T23:59:59.000Z

237

Means and method for vapor generation  

DOE Patents (OSTI)

A liquid, in heat transfer contact with a surface heated to a temperature well above the vaporization temperature of the liquid, will undergo a multiphase (liquid-vapor) transformation from 0% vapor to 100% vapor. During this transition, the temperature driving force or heat flux and the coefficients of heat transfer across the fluid-solid interface, and the vapor percentage influence the type of heating of the fluid--starting as "feedwater" heating where no vapors are present, progressing to "nucleate" heating where vaporization begins and some vapors are present, and concluding with "film" heating where only vapors are present. Unstable heating between nucleate and film heating can occur, accompanied by possibly large and rapid temperature shifts in the structures. This invention provides for injecting into the region of potential unstable heating and proximate the heated surface superheated vapors in sufficient quantities operable to rapidly increase the vapor percentage of the multiphase mixture by perhaps 10-30% and thereby effectively shift the multiphase mixture beyond the unstable heating region and up to the stable film heating region.

Carlson, Larry W. (Oswego, IL)

1984-01-01T23:59:59.000Z

238

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

DOE Green Energy (OSTI)

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

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

1979-01-01T23:59:59.000Z

239

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

E-Print Network (OSTI)

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

Kelley, Randy Dean

2010-08-01T23:59:59.000Z

240

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

Science Conference Proceedings (OSTI)

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

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

2007-08-23T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

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

DOE Green Energy (OSTI)

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

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

2011-02-14T23:59:59.000Z

242

Effect of higher water vapor content on TBC performance  

Science Conference Proceedings (OSTI)

Coal gasification, or IGCC (integrated gasification combined cycle), is one pathway toward cleaner use of coal for power generation with lower emissions. However, when coal-derived synthesis gas (i.e., syngas) is burned in turbines designed for natural gas, turbine manufacturers recommend 'derating,' or lowering the maximum temperature, which lowers the efficiency of the turbine, making electricity from IGCC more expensive. One possible reason for the derating is the higher water vapor contents in the exhaust gas. Water vapor has a detrimental effect on many oxidation-resistant high-temperature materials. In a turbine hot section, Ni-base superalloys are coated with a thermal barrier coating (TBC) allowing the gas temperature to be higher than the superalloy solidus temperature. TBCs have a low thermal conductivity ceramic top coating (typically Y{sub 2}O{sub 3}-stabilized ZrO{sub 2}, or YSZ) and an oxidation-resistant metallic bond coating. For land-based gas turbines, the industry standard is air plasma sprayed (APS) YSZ and high velocity oxygen fuel (HVOF) sprayed NiCoCrAlY bond coatings. To investigate the role of higher water vapor content on TBC performance and possible mitigation strategies, furnace cycling experiments were conducted in dry O{sub 2} and air with 10% (typical with natural gas or jet fuel) or 50 vol% water vapor. Cycle frequency and temperature were accelerated to one hour at 1100 C (with 10 minute cooling to {approx}30 C between each thermal cycle) to induce early failures in coatings that are expected to operate for several years with a metal temperature of {approx}900 C. Coupons (16 mm diameter x 2 mm thick) of commercial second-generation single crystal superalloy CMSX4 were HVOF coated on both sides with {approx}125 {micro}m of Ni-22wt%Co-17Cr-12Al either with 0.7Y or 0.7Y-0.3Hf-0.4Si. One side was then coated with 190-240 {micro}m of APS YSZ. Coatings were cycled until the YSZ top coating spalled. Figure 2 shows the results of the initial phase of experiments. Compared to dry O{sub 2}, the addition of 10% water vapor decreased the lifetime of MCrAlY by {approx}30% for the conventional CMSX4 substrates. Higher average lifetimes were observed with Hf in the bond coating, but a similar decrease in lifetime was observed when water vapor was added. The addition of Y and La to the superalloy substrate did not change the YSZ lifetime with 10% water vapor. However, increasing water vapor content from 10 to 50% did not further decrease the lifetime of either bond coating with the doped superalloy substrate. Thus, these results suggest that higher water vapor contents cannot explain the derating of syngas-fired turbines, and other factors such as sulfur and ash from imperfect syngas cleanup (or upset conditions) need to be explored. Researchers continue to study effects of water vapor on thermally grown alumina scale adhesion and growth rate, and are looking for bond coating compositions more resistant to oxidation in the presence of water vapor.

Pint, Bruce A [ORNL; Haynes, James A [ORNL

2012-01-01T23:59:59.000Z

243

A Phase-Field Model for ?-Zirconium Hydride Formation in Single  

Science Conference Proceedings (OSTI)

Conference Tools for 2012 TMS Annual Meeting & Exhibition ... Scope, Zirconium alloys are extensively utilized as structural materials in nuclear energy industry for nuclear fuel cladding. ... Cluster Expansion Methods - Progress and Outlook.

244

New Regenerative Cycle for Vapor Compression Refrigeration  

SciTech Connect

The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic properties of gas, such as flow rate, speed and acceleration. The substance of this proposal is a thermodynamic cycle characterized by the regenerative use of the potential energy of two-phase flow expansion, which in traditional systems is lost in expansion valves. The essential new features of the process are: (1) The application of two-step throttling of the working fluid and two-step compression of its vapor phase. (2) Use of a compressor as the initial step compression and a jet device as a second step, where throttling and compression are combined. (3) Controlled ratio of a working fluid at the first and second step of compression. In the proposed system, the compressor compresses the vapor only to 50-60% of the final pressure, while the additional compression is provided by a jet device using internal potential energy of the working fluid flow. Therefore, the amount of mechanical energy required by a compressor is significantly reduced, resulting in the increase of efficiency (either COP or EER). The novelty of the cycle is in the equipment and in the way the multi-staging is accomplished. The anticipated result will be a new refrigeration system that requires less energy to accomplish a cooling task. The application of this technology will be for more efficient designs of: (1) Industrial chillers, (2) Refrigeration plants, (3) Heat pumps, (4) Gas Liquefaction plants, (5) Cryogenic systems.

Mark J. Bergander

2005-08-29T23:59:59.000Z

245

Enhanced frequency up-conversion in Rb vapor  

E-Print Network (OSTI)

We demonstrate highly efficient generation of coherent 420 nm light via up-conversion of near-infrared lasers in a hot rubidium vapor cell. By optimizing pump polarizations and frequencies we achieve a single-pass conversion efficiency of 260%/W, significantly higher than in previous experiments. A full 2D exploration of the coherent light generation and fluorescence as a function of the pump frequencies reveals that coherent blue light is generated at 85Rb two-photon resonances, as predicted by theory, but at high vapor pressure it is suppressed in spectral regions that don't support phase matching or exhibit single-photon Kerr refraction. Favorable scaling of our current 1 mW blue beam power with additional pump power is predicted. Infrared pump polarization could be used for future intensity switching experiments.

Vernier, A; Riis, E; Arnold, A S

2009-01-01T23:59:59.000Z

246

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

247

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

DOE Green Energy (OSTI)

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

Clayton, J C

1987-10-01T23:59:59.000Z

248

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

DOE Green Energy (OSTI)

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

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

1999-03-01T23:59:59.000Z

249

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

E-Print Network (OSTI)

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

Mosegaard, Klaus

250

STANDARDIZED TESTING PROGRAM FOR EMERGENT CHEMICAL HYDRIDE AND CARBON STORAGE TECHNOLOGIES  

E-Print Network (OSTI)

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

251

Preparation of Prototypic Irradiated Hydrided-Zircaloy Cladding for UFDC Programs  

SciTech Connect

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

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

2013-01-01T23:59:59.000Z

252

Coupling apparatus for a metal vapor laser  

DOE Patents (OSTI)

Coupling apparatus for a large bore metal vapor laser is disclosed. The coupling apparatus provides for coupling high voltage pulses (approximately 40 KV) to a metal vapor laser with a high repetition rate (approximately 5 KHz). The coupling apparatus utilizes existing thyratron circuits and provides suitable power input to a large bore metal vapor laser while maintaining satisfactory operating lifetimes for the existing thyratron circuits.

Ball, D.G.; Miller, J.L.

1993-02-23T23:59:59.000Z

253

Mercury Vapor (Kooten, 1987) | Open Energy Information  

Open Energy Info (EERE)

Mercury Vapor (Kooten, 1987) Mercury Vapor (Kooten, 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor (Kooten, 1987) Exploration Activity Details Location Unspecified Exploration Technique Mercury Vapor Activity Date Usefulness useful DOE-funding Unknown Notes Surface soil-mercury surveys are an inexpensive and useful exploration tool for geothermal resources. ---- Surface geochemical surveys for mercury were conducted in 16 areas in 1979-1981 by ARCO Oil and Gas Company as part of its geothermal evaluation program. Three techniques used together have proved satisfactory in evaluating surface mercury data. These are contouring, histograms and cumulative frequency plots of the data. Contouring geochemical data and constructing histograms are standard

254

Thermoplastic Composite with Vapor Grown Carbon Fiber.  

E-Print Network (OSTI)

??Vapor grown carbon fiber (VGCF) is a new class of highly graphitic carbon nanofiber and offers advantages of economy and simpler processing over continuous-fiber composites. (more)

Lee, Jaewoo

2005-01-01T23:59:59.000Z

255

Moisture Durability of Vapor Permeable Insulating Sheathing ...  

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

Existing Homes, Building Technologies Office (BTO) In this project, Building America team Building Science Corporation researched some of the ramifications of using exterior, vapor...

256

Field Studies of Soil Vapor Intrusion at a Vacant Manufactured Gas Plant (MGP) Site in Wisconsin  

Science Conference Proceedings (OSTI)

A comprehensive two-phase field-based research program was completed at a former manufactured gas plant (MGP) site located in Wisconsin during the summer of 2008. The purpose of this ongoing research study is to develop improved approaches and methodologies for characterizing the potential for vapor intrusion (VI) at MGP sites. This report describes the methods, results, and limited data interpretation of Phase I (Passive Soil Gas Survey) and Phase II (Soil, Groundwater, and Soil Gas Sampling) at the vac...

2009-06-30T23:59:59.000Z

257

Water Vapor Fields Deduced from METEOSAT-1 Water Vapor Channel Data  

Science Conference Proceedings (OSTI)

A quasi-operational process for the determination of water vapor fields from METEPSAT-1 water vapor channel data is described. Each count of the WV picture is replaced by the corresponding mean relative humidity value using both the calibration ...

M. M. Poc; M. Roulleau

1983-09-01T23:59:59.000Z

258

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

DOE Green Energy (OSTI)

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

Colombo, P; Steinberg, M

1976-01-01T23:59:59.000Z

259

G-Band Vapor Radiometer Precipitable Water Vapor (GVRPWV) Value-Added Product  

SciTech Connect

The G-Band Vapor Radiometer Precipitable Water Vapor (GVRPWV) value-added product (VAP) computes precipitable water vapor using neural network techniques from data measured by the GVR. The GVR reports time-series measurements of brightness temperatures for four channels located at 183.3 1, 3, 7, and 14 GHz.

Koontz, A; Cadeddu, M

2012-12-05T23:59:59.000Z

260

Near real time vapor detection and enhancement using aerosol adsorption  

DOE Patents (OSTI)

A vapor sample detection method where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample.

Novick, Vincent J.; Johnson, Stanley A.

1997-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

Tenth Biennial Workshop on Organometallic Vapor Phase Epitaxy  

Science Conference Proceedings (OSTI)

Mar 15, 2001 ... National Renewable Energy Lab. Dr. Simon Watkins. Simon Fraser ..... Payment shall be made in US dollars drawn on a US bank. r Credit Card...

262

Organic lateral heterojunction devices for vapor-phase chemical detection  

E-Print Network (OSTI)

As the U.S. is engaged in battle overseas, there is an urgent need for the development of sensors for early warning and protection of military forces against potential attacks. On the battlefields, improvised explosive ...

Ho, John C., 1980-

2009-01-01T23:59:59.000Z

263

Regular Transient Loading Response in a Vapor-Phase  

E-Print Network (OSTI)

from a POTW using a compost bio?lter. Water Environ. Res.heat and mass transport within a compost bio?lter: I. ModelM. A. ?1995?. Operation of compost based bio?lters under

Wright, W F; Schroeder, E D; Chang, Daniel P.Y.

2005-01-01T23:59:59.000Z

264

Metal Organic Vapor Phase Epitaxy ICMOVPE-XV  

Science Conference Proceedings (OSTI)

Growth of Energy Technology (solid state lighting, PV, Thermoelectrics, etc) ..... treatment prices when booked in advance for the attendees and guests of.

265

Ninth International Conference on Metal Organic Vapor Phase ...  

Science Conference Proceedings (OSTI)

Free sample copies of III-Vs Review and information on the Advanced ... on the market an innovative surface contamination analysis with the powerful TOF SIMS ... NIMTEC, located in Chandler, AZ, is a subsidiary of Japan Energy that sells...

266

Regular Transient Loading Response in a Vapor-Phase  

E-Print Network (OSTI)

JOURNAL OF ENVIRONMENTAL ENGINEERING ASCE / DECEMBER 2005ENVIRONMENTAL ENGINEERING ASCE / DECEMBER 2005 / 1657 nol.must be ?led with the ASCE Managing Editor. The manuscript

Wright, W F; Schroeder, E D; Chang, Daniel P.Y.

2005-01-01T23:59:59.000Z

267

Ninth International Conference on Metal Organic Vapor Phase ...  

Science Conference Proceedings (OSTI)

Hertz Rent-a-Car System has been selected as the Official Car Rental Company for the ICMOVPE IX. Special rates are being offered and will be honored up to...

268

Metal Hydrides for Thermal Energy Storage Applications - A review  

Science Conference Proceedings (OSTI)

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

269

Atomic vapor laser isotope separation  

SciTech Connect

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

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

1985-11-08T23:59:59.000Z

270

A New Global Water Vapor Dataset  

Science Conference Proceedings (OSTI)

A comprehensive and accurate global water vapor dataset is critical to the adequate understanding of water vapor's role in the earth's climate system. To begin to satisfy this need, the authors have produced a blended dataset made up of global, 5-...

David L. Randel; Thomas J. Greenwald; Thomas H. Vonder Haar; Graeme L. Stephens; Mark A. Ringerud; Cynthia L. Combs

1996-06-01T23:59:59.000Z

271

LNG fire and vapor control system technologies  

SciTech Connect

This report provides a review of fire and vapor control practices used in the liquefied natural gas (LNG) industry. Specific objectives of this effort were to summarize the state-of-the-art of LNG fire and vapor control; define representative LNG facilities and their associated fire and vapor control systems; and develop an approach for a quantitative effectiveness evaluation of LNG fire and vapor control systems. In this report a brief summary of LNG physical properties is given. This is followed by a discussion of basic fire and vapor control design philosophy and detailed reviews of fire and vapor control practices. The operating characteristics and typical applications and application limitations of leak detectors, fire detectors, dikes, coatings, closed circuit television, communication systems, dry chemicals, water, high expansion foam, carbon dioxide and halogenated hydrocarbons are described. Summary descriptions of a representative LNG peakshaving facility and import terminal are included in this report together with typical fire and vapor control systems and their locations in these types of facilities. This state-of-the-art review identifies large differences in the application of fire and vapor control systems throughout the LNG industry.

Konzek, G.J.; Yasutake, K.M.; Franklin, A.L.

1982-06-01T23:59:59.000Z

272

Quantitative organic vapor-particle sampler  

DOE Patents (OSTI)

A quantitative organic vapor-particle sampler for sampling semi-volatile organic gases and particulate components. A semi-volatile organic reversible gas sorbent macroreticular resin agglomerates of randomly packed microspheres with the continuous porous structure of particles ranging in size between 0.05-10 .mu.m for use in an integrated diffusion vapor-particle sampler.

Gundel, Lara (Berkeley, CA); Daisey, Joan M. (Walnut Creek, CA); Stevens, Robert K. (Cary, NC)

1998-01-01T23:59:59.000Z

273

Low Frequency Acoustic Resonance Studies of the Liquid-Vapor Transition in Silica Aerogel  

E-Print Network (OSTI)

Fluid phase transitions in porous media are a powerful probe of the effect of confinement and disorder on phase transitions. Aerogel may provide a model system in which to study the effect of dilute impurities on a variety of phase transitions. In this paper we present a series of low frequency acoustic experiments on the effect of aerogel on the liquid-vapor phase transition. Acoustic resonators were used to study the liquid-vapor transition in two fluids (helium and neon) and in two different porosity aerogels (95% and 98%). While effective coexistence curves could be mapped out, the transition was sometimes difficult to pinpoint, leading to doubt as to whether this transition can be treated as an equilibrium macroscopic phase transition at all.

Tobias Herman; John Beamish

2005-06-30T23:59:59.000Z

274

Stacked vapor fed amtec modules  

DOE Patents (OSTI)

The present invention pertains to a stacked AMTEC module. The invention includes a tubular member which has an interior. The member is comprised of a ion conductor that substantially conducts ions relative to electrons, preferably a beta"-alumina solid electrolyte, positioned about the interior. A porous electrode for conducting electrons and allowing sodium ions to pass therethrough, and wherein electrons and sodium ions recombine to form sodium is positioned about the beta"-alumina solid electrolyte. The electrode is operated at a temperature and a pressure that allows the recombined sodium to vaporize. Additionally, an outer current collector grid for distributing electrons throughout the porous electrode is positioned about and contacts the porous electrode. Also included in the invention is transporting means for transporting liquid sodium to the beta"-alumina solid electrolyte of the tubular member. A transition piece is positioned about the interior of the member and contacts the transporting means. The transition piece divides the member into a first cell and a second cell such that each first and second cell has a beta"-alumina solid electrolyte, a first and second porous electrode and a grid. The transition piece conducts electrons from the interior of the tubular member. There is supply means for supplying sodium to the transporting means. Preferably the supply means is a shell which surrounds the tubular member and is operated at a temperature such that the vaporized sodium condenses thereon. Returning means for returning the condensed sodium from the shell to the transporting means provides a continuous supply of liquid sodium to the transporting means. Also, there are first conducting means for conducting electric current from the transition piece which extends through the shell, and second conducting means for conducting electric current to the grid of the first cell which extends through the shell.

Sievers, Robert K. (North Huntingdon, PA)

1989-01-01T23:59:59.000Z

275

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

DOE Green Energy (OSTI)

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

Fox, K

2007-11-08T23:59:59.000Z

276

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

277

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

DOE Green Energy (OSTI)

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

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

1996-03-01T23:59:59.000Z

278

ARM - Field Campaign - Water Vapor IOP  

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

govCampaignsWater Vapor IOP govCampaignsWater Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Water Vapor IOP 2000.09.18 - 2000.10.08 Lead Scientist : Henry Revercomb Data Availability Yes For data sets, see below. Description Scientific hypothesis: 1. Microwave radiometer (MWR) observations of the 22 GHz water vapor line can accurately constrain the total column amount of water vapor (assuming a calibration accuracy of 0.5 degC or better, which translates into 0.35 mm PWV). 2. Continuous profiling by Raman lidar provides a stable reference for handling sampling problems and observes a fixed column directly above the site only requiring a single height- independent calibration factor. 3. Agreement between the salt-bath calibrated in-situ probes, chilled

279

Mercury Vapor At Desert Peak Area (Varekamp & Buseck, 1983) ...  

Open Energy Info (EERE)

Mercury Vapor At Desert Peak Area (Varekamp & Buseck, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Desert Peak Area...

280

Mercury Vapor At Socorro Mountain Area (Kooten, 1987) | Open...  

Open Energy Info (EERE)

Mercury Vapor At Socorro Mountain Area (Kooten, 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Socorro Mountain Area...

Note: This page contains sample records for the topic "hydride vapor phase" 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

Abstract: Apparatus for Measuring Vapor-Liquid Equilibrium ...  

Science Conference Proceedings (OSTI)

... Measurements of the vapor pressures and saturated liquid densities of ethanol and the vapor pressure of an ethanol water mixture (ethanol=0.6743 ...

282

Mercury Vapor At Mccoy Geothermal Area (DOE GTP) | Open Energy...  

Open Energy Info (EERE)

Mercury Vapor At Mccoy Geothermal Area (DOE GTP) Exploration Activity Details Location Mccoy Geothermal Area Exploration Technique Mercury Vapor Activity Date Usefulness not...

283

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

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

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

284

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

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

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

285

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

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

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

286

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

287

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

Science Conference Proceedings (OSTI)

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

Greenspan, E

2006-04-30T23:59:59.000Z

288

Water vapor retrieval over many surface types  

SciTech Connect

In this paper we present a study of of the water vapor retrieval for many natural surface types which would be valuable for multi-spectral instruments using the existing Continuum Interpolated Band Ratio (CIBR) for the 940 nm water vapor absorption feature. An atmospheric code (6S) and 562 spectra were used to compute the top of the atmosphere radiance near the 940 nm water vapor absorption feature in steps of 2.5 nm as a function of precipitable water (PW). We derive a novel technique called ``Atmospheric Pre-corrected Differential Absorption`` (APDA) and show that APDA performs better than the CIBR over many surface types.

Borel, C.C.; Clodius, W.C.; Johnson, J.

1996-04-01T23:59:59.000Z

289

Modeling engine oil vaporization and transport of the oil vapor in the piston ring pack on internal combustion engines.  

E-Print Network (OSTI)

??A model was developed to study engine oil vaporization and oil vapor transport in the piston ring pack of internal combustion engines. With the assumption (more)

Cho, Yeunwoo, 1973-

2004-01-01T23:59:59.000Z

290

Analysis of binary vapor turbines  

DOE Green Energy (OSTI)

The effect the binary mixture has on the turbine is examined in terms of design and cost. Several flow theories for turbines and turbine blading are reviewed. The similarity method, which uses dimensionless parameters, is used in determining rotative speeds and diameters for a variety of inlet temperatures and exit pressures. It is shown that the ratio of exit to inlet specific volume for each component in the mixture is the same for each specie. The specific volume ratio constraints are combined with the temperature equalities, the condenser pressure, and the total inlet entropy to form the constraints necessary to determine the exit state uniquely in an isentropic expansion. The non-isentropic exit state is found in a similar manner. The expansion process is examined for several cases and compared with the expansion of a single component vapor. Finally, in order to maintain high efficiency and to meet the criteria which makes the similarity method valid at high inlet temperatures, turbine multistaging is examined and a sample case is given for a two stage turbine.

Bliss, R.W.; Boehm, R.F.; Jacobs, H.R.

1976-12-01T23:59:59.000Z

291

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

DOE Green Energy (OSTI)

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

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

2011-07-14T23:59:59.000Z

292

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

Science Conference Proceedings (OSTI)

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

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

2012-02-01T23:59:59.000Z

293

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

DOE Green Energy (OSTI)

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

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

2001-01-01T23:59:59.000Z

294

Developmental of a Vapor Cloud Explosion Risk Analysis Tool Using Exceedance Methodology  

E-Print Network (OSTI)

In development projects, designers should take into consideration the possibility of a vapor cloud explosion in the siting and design of a process plant from day one. The most important decisions pertinent to the location of different process areas, separation between different areas, location of occupied buildings and overall layout may be made at the conceptual stage of the project. During the detailed design engineering stage the final calculation of gas explosion loads is an important activity. However, decisions related to the layout and location of occupied buildings at this stage could be very costly. Therefore, at the conceptual phase of the development project for a hydrocarbon facility, it would be helpful to get a picture of possible vapor cloud explosion loads to be used in studying various options. This thesis presents the analytical parameters that are used in vapor cloud explosion risk analysis. It proposes a model structure for the analysis of vapor cloud explosion risks to buildings based on exceedance methodology. This methodology was developed in a computer program which is used to support this thesis. The proposed model considers all possible gas release scenarios through the use of the Monte Carlo simulation. The risk of vapor cloud explosions can be displayed using exceedance curves. The resulting model provides a predictive tool for vapor cloud explosion problems at the early stages of development projects, particularly in siting occupied buildings in onshore hydrocarbon facilities. It can also be used as a quick analytical tool for investigating various aspects of vapor cloud explosions. This model has been applied to a case study, a debutanizer process unit. The model was used to explore the different alternatives of locating a building near the facility. The results from the model were compared to the results of other existing software to determine the model validity. The results show that the model can effectively examine the risk of vapor cloud explosions.

Alghamdi, Salem

2011-08-01T23:59:59.000Z

295

Observed annual and interannual variations in tropospheric water vapor  

SciTech Connect

Radiosonde observations from a global network of 56 radiosonde stations for 1973-1990 are used to describe and quantify annual and interannual variations of tropospheric water vapor. Taking care to identify data inhomogeneities related to changes in instruments or observing practices, monthly mean and anomaly data sets are constructed for dew point, specific humidity, relative humidity, temperature and precipitable water from the surface to 500 mb. Local annual cycles of tropospheric humidity can be classified according to the amplitude and phase of humidity variations which define five humidity regimes. For two regimes, both in middle and high latitudes, relative humidity is fairly constant while the annual cycle of precipitable water is in phase with that of temperature. At some midlatitude stations with a monsoon-like climate, seasonal relative humidity variations are large. In the tropics, seasonal relative humidity variations, especially above the boundary layer, dominate the annual cycle of precipitable water, and precipitable water variations are not related to temperature variations. Correlations of temperature and specific humidity anomalies are generally positive outside the tropics, suggesting that atmospheric warming is associated with increases in water vapor content. However, correlations of temperature and relative humidity anomalies are sometimes not significant and are often negative (e.g., in mid- and high latitude continental regions). Thus relative humidity is not always insensitive to temperature changes. In the tropics, tropospheric water vapor and temperature variations are not well correlated. An empirical orthogonal function analysis of tropical specific humidity variations identified two important modes of variability. The first is a step-like increase in specific humidity that occurred in about 1976-1977, and the second is associated with the El Nino phenomenon.

Gaffen, D.J.

1992-01-01T23:59:59.000Z

296

Perfluorocarbon vapor tagging of blasting cap detonators  

DOE Patents (OSTI)

A plug for a blasting cap is made of an elastomer in which is dissolved a perfluorocarbon. The perfluorocarbon is released as a vapor into the ambient over a long period of time to serve as a detectable taggant.

Dietz, Russell N. (Shoreham, NY); Senum, Gunnar I. (Patchogue, NY)

1981-01-01T23:59:59.000Z

297

Perfluorocarbon vapor tagging of blasting cap detonators  

SciTech Connect

A plug for a blasting cap is made of an elastomer in which is dissolved a perfluorocarbon. The perfluorocarbon is released as a vapor into the ambient over a long period of time to serve as a detectable taggant.

Dietz, R.N.; Senum, G.I.

1981-03-17T23:59:59.000Z

298

Chemical vapor deposition of antimicrobial polymer coatings  

E-Print Network (OSTI)

There is large and growing interest in making a wide variety of materials and surfaces antimicrobial. Initiated chemical vapor deposition (iCVD), a solventless low-temperature process, is used to form thin films of polymers ...

Martin, Tyler Philip, 1977-

2007-01-01T23:59:59.000Z

299

Chemical vapor deposition of functionalized isobenzofuran polymers  

E-Print Network (OSTI)

This thesis develops a platform for deposition of polymer thin films that can be further tailored by chemical surface modification. First, we explore chemical vapor deposition of functionalized isobenzofuran films using ...

Olsson, Ylva Kristina

2007-01-01T23:59:59.000Z

300

Tropospheric Water Vapor and Climate Sensitivity  

Science Conference Proceedings (OSTI)

Estimates are made of the effect of changes in tropospheric water vapor on the climate sensitivity to doubled carbon dioxide (CO2), using a coarse resolution atmospheric general circulation model coupled to a slab mixed layer ocean. The ...

Edwin K. Schneider; Ben P. Kirtman; Richard S. Lindzen

1999-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

Chemical vapor depositing of metal fluorides  

Science Conference Proceedings (OSTI)

High Purity BeF2 and BeF2AlF3glasses have been deposited by the chemical vapor deposition technique using beryllium and aluminum 1

A. Sarhangi; J. M. Power

1992-01-01T23:59:59.000Z

302

Chemical vapor infiltration using microwave energy  

DOE Patents (OSTI)

This invention is comprised of a method for producing reinforced ceramic composite articles by means of chemical vapor infiltration and deposition in which an inverted temperature gradient is utilized. Microwave energy is the source of heat for the process.

Devlin, D.J.; Currier, R.P.; Laia, J.R.; Barbero, R.S.

1992-12-31T23:59:59.000Z

303

Kinetic and Prediction of Hydrogen Outgassing from Lithium Hydride  

DOE Green Energy (OSTI)

In most industrial or device applications, LiH is placed in either an initially dry or a vacuum environment with other materials that may release moisture slowly over many months, years, or even decades. In such instances, the rate of hydrogen outgassing from the reaction of LiH with H{sub 2}O can be reasonably approximated by the rate at which H{sub 2}O is released from the moisture containing materials. In a vacuum or dry environment, LiOH decomposes slowly with time into Li{sub 2}O even at room temperature according to: 2LiOH(s) {yields} Li{sub 2}O(s) + H{sub 2}O(g) (1). The kinetics of the decomposition of LiOH depends on the dryness/vacuum level and temperature. It was discovered by different workers that vacuum thermal decomposition of bulk LiOH powder (grain sizes on the order of tens to hundreds of micrometers) into Li{sub 2}O follows a reaction front moving from the surface inward. Due to stress at the LiOH/vacuum interface and defective and missing crystalline bonding at surface sites, lattice vibrations at the surfaces/interfaces of most materials are at frequencies different than those in the bulk, a phenomenon observed in most solids. The chemical reactivity and electronic properties at surfaces and interfaces of materials are also different than those in the bulk. It is, therefore, expected that the amount of energy required to break bonds at the LiOH/vacuum interface is not as large as in the bulk. In addition, in an environment where there is a moisture sink or in the case of a continuously pumped vacuum chamber, H{sub 2}O vapor is continuously removed and LiOH decomposes into Li{sub 2}O from the LiOH/vacuum interface (where it is thermally less stable) inward according to reaction (1) in an effort to maintain the equilibrium H{sub 2}O vapor pressure at the sample/vacuum interface. In a closed system containing both LiH and LiOH, the H{sub 2}O released from the decomposition of LiOH reacts with LiH to form hydrogen gas according to the following reaction: 2LiH(s) + H{sub 2}O(g) {yields} Li{sub 2}O(s) +2H{sub 2}(g) + heat (2). Such is the case of vacuum thermal decomposition of a corrosion layer previously grown on top of a LiH substrate. Here, the huge H{sub 2}O concentration gradient across the Li{sub 2}O buffer layer in between the hydrophilic LiH substrate and LiOH, coupled with the defective nature of LiOH at surfaces/interfaces as discussed above, effectively lowers the energy barrier for LiOH decomposition here in comparison with bulk LiOH and turns the LiH substrate into an effective moisture pump. As a result, in the case of vacuum thermal decomposition of LiOH on top of a LiH substrate, the LiOH decomposition front starts at the LiH/Li{sub 2}O/LiOH interface. As a function of increasing time and temperature, the Li{sub 2}O layer in between LiH and LiOH gets thicker, causing the energy barrier for the LiOH decomposition at the LiOH/Li{sub 2}O/LiH interface to increase, and eventually LiOH at the LiOH/vacuum interface also starts to decompose into Li{sub 2}O for reasons described in the previous paragraph. Thereafter, the Li{sub 2}O fronts keep moving inward from all directions until all the LiOH is gone. This vacuum thermal decomposition process of LiOH previously grown on top of a LiH substrate is illustrated in the cartoon of figure 1.

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

2006-08-31T23:59:59.000Z

304

CORRELATIONS BETWEEN VAPOR SATURATION, FLUID COMPOSITION, AND WELL DECLINE IN LARDERELLO  

Science Conference Proceedings (OSTI)

A large body of field data from Larderello shows striking temporal correlations between decline of well flow-rate, produced gas/steam ratio, chloride concentration and produced vapor fraction. The latter is inferred from measured concentrations of non-condensible gases in samples of well fluid, using chemical phase equilibrium principles. Observed temporal changes in the vapor fractions can be interpreted in term of a ''multiple source'' model, as suggested by D'Amore and Truesdell (1979). This provides clues to the dynamics of reservoir depletion, and to the evaluation of well productivity and longevity.

D'Amore, F.; Pruess, K.

1985-01-22T23:59:59.000Z

305

Numerical simulation of transient, incongruent vaporization induced by high power laser  

Science Conference Proceedings (OSTI)

A mathematical model and numerical calculations were developed to solve the heat and mass transfer problems specifically for uranum oxide subject to laser irradiation. It can easily be modified for other heat sources or/and other materials. In the uranium-oxygen system, oxygen is the preferentially vaporizing component, and as a result of the finite mobility of oxygen in the solid, an oxygen deficiency is set up near the surface. Because of the bivariant behavior of uranium oxide, the heat transfer problem and the oxygen diffusion problem are coupled and a numerical method of simultaneously solving the two boundary value problems is studied. The temperature dependence of the thermal properties and oxygen diffusivity, as well as the highly ablative effect on the surface, leads to considerable non-linearities in both the governing differential equations and the boundary conditions. Based on the earlier work done in this laboratory by Olstad and Olander on Iron and on Zirconium hydride, the generality of the problem is expanded and the efficiency of the numerical scheme is improved. The finite difference method, along with some advanced numerical techniques, is found to be an efficient way to solve this problem.

Tsai, C.H.

1981-01-01T23:59:59.000Z

306

Page 1 of 2 `5-Phase' EOS: A Tabular H2O EOS for Shock Physics Codes  

E-Print Network (OSTI)

of the Table The 5-Phase H2O tabular equation of state model includes ice Ih, ice VI, ice VII, liquid determined phase boundaries except for the artificial ice Ih-ice VI boundary and the adjacent liquid boundary density phase boundary occupied by the equilibrium mixtures of ice Ih-vapor and liquid-vapor. The tension

Stewart, Sarah T.

307

The influence of ice nucleation mode and ice vapor growth on simulation of  

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

The influence of ice nucleation mode and ice vapor growth on simulation of The influence of ice nucleation mode and ice vapor growth on simulation of arctic mixed-phase clouds Avramov, Alexander The Pennsylvania State University Category: Modeling Mixed-phase arctic stratus clouds are the predominant cloud type in the Arctic . Perhaps one of the most intriguing of their features is that they tend to have liquid tops that precipitate ice. Despite the fact that this situation is colloidally unstable, these cloud systems are quite long lived - from a few days to over a couple of weeks. Previous studies have suggested that this longevity may be due to a paucity of ice nucleating aerosols (ice nuclei, or IN) in the Arctic. Such studies have shown that small changes in IN concentrations can cause large changes in the amount of liquid water within a mixed-phase stratus deck. We use the Regional

308

Vapor scavenging by atmospheric aerosol particles  

Science Conference Proceedings (OSTI)

Particle growth due to vapor scavenging was studied using both experimental and computational techniques. Vapor scavenging by particles is an important physical process in the atmosphere because it can result in changes to particle properties (e.g., size, shape, composition, and activity) and, thus, influence atmospheric phenomena in which particles play a role, such as cloud formation and long range transport. The influence of organic vapor on the evolution of a particle mass size distribution was investigated using a modified version of MAEROS (a multicomponent aerosol dynamics code). The modeling study attempted to identify the sources of organic aerosol observed by Novakov and Penner (1993) in a field study in Puerto Rico. Experimentally, vapor scavenging and particle growth were investigated using two techniques. The influence of the presence of organic vapor on the particle`s hydroscopicity was investigated using an electrodynamic balance. The charge on a particle was investigated theoretically and experimentally. A prototype apparatus--the refractive index thermal diffusion chamber (RITDC)--was developed to study multiple particles in the same environment at the same time.

Andrews, E.

1996-05-01T23:59:59.000Z

309

High-pressure vapor-liquid equilibria in the propane-1-propanol system  

SciTech Connect

High-pressure isothermal vapor liquid equilibrium data were measured for the propane-1-propanol system at 81.6, 105.2, and 120.1 C in a static equilibrium cell with liquid-phase sampling by a piston-driven sampling rod and homogenizing the sample with a static jet mixer. The vapor phase was sampled by releasing it into an evacuated manifold, and the gas chromatograph was calibrated with a new variable volumetric device. Satisfactory modeling was achieved with the combined method using the UNIQUAC equation with equations of sate: the group contribution EOS, Peng-Robinson EOS, or the two-parameter Virial EOS. Differences between the measured and calculated vapor-phase mole fractions, however, were significant for the lower pressure regions of the 81.6 and 120.1 C isotherms. UNIQUAC parameters, hitherto unavailable, with fairly strong temperature dependence in the 81.6 to 120.1 C range are proposed for the system. The covariance matrix indicated a significant correlation among the parameters. The classical mixing rule interaction parameters required for the original Peng-Robinson EOS in the combined method were obtained using the direct method and were temperature-independent for the isotherms for which the propane was supercritical. The possibility of propane/1-propanol immiscibility was theoretically examined according to the criteria of Baker et al. The plots of Gibbs energy of mixing vs. phase mole fractions did not indicate liquid-phase splitting, but the inferences are EOS-dependent and must await visual confirmation. The authors earlier vapor-phase thermodynamic consistency test indicated the data for all three data sets not to be inconsistent.

Muehlbauer, A.L.; Raal, J.D. (Univ. of Natal, Durban (South Africa))

1993-04-01T23:59:59.000Z

310

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

DOE Green Energy (OSTI)

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

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

1996-12-31T23:59:59.000Z

311

Design of a microbreather for two-phase microchannel devices  

E-Print Network (OSTI)

Multiphase flows in microchannels are encountered in a variety of microfluidic applications. Two-phase microchannel heat sinks leverage the latent heat of vaporization to offer an efficient method of dissipating large heat ...

Alexander, Brentan R

2008-01-01T23:59:59.000Z

312

Micro and nanostructured surfaces for enhanced phase change heat transfer  

E-Print Network (OSTI)

Two-phase microchannel heat sinks are of significant interest for thermal management applications, where the latent heat of vaporization offers an efficient method to dissipate large heat fluxes in a compact device. However, ...

Chu, Kuang-Han, Ph. D. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

313

Gas phase 129Xe NMR imaging and spectroscopy  

E-Print Network (OSTI)

5 l l Dynamic NMR microscopy of gas phase Poiseuille flowmetal vapors and noble gases can be used to efficientlypolarize the nuclei ofthe noble-gas atoms. As a result, the

Kaiser, Lana G.

2010-01-01T23:59:59.000Z

314

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

Science Conference Proceedings (OSTI)

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

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

1988-06-01T23:59:59.000Z

315

ARM - Field Campaign - Water Vapor IOP  

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

govCampaignsWater Vapor IOP govCampaignsWater Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Water Vapor IOP 1996.09.10 - 1996.09.30 Lead Scientist : Henry Revercomb For data sets, see below. Summary SCHEDULE This IOP will be conducted from September 10 - 30, 1996 (coincident with the Fall ARM-UAV IOP). Instruments that do not require supervision will be operated continuously during this period. Instruments that do require supervision are presently planned to be operated for 8-hour periods each day. Because it is necessary to cover as broad a range of environmental conditions as possible, the daily 8-hour period will be shifted across the diurnal cycle as deemed appropriate during the IOP (but will be maintained as a contiguous 8-hour block).

316

atmospheric water vapor | OpenEI  

Open Energy Info (EERE)

atmospheric water vapor atmospheric water vapor Dataset Summary Description (Abstract): Monthly Average Solar Resource for 2-axis tracking concentrating collectors for Mexico, Central America, and the Caribbean Islands. (Purpose): Provide information on the solar resource potential for the data domain. The insolation values represent the average solar energy available to a concentrating collector, such as a dish collector, which tracks the sun continuously. Source NREL Date Released July 31st, 2006 (8 years ago) Date Updated October 30th, 2007 (7 years ago) Keywords atmospheric water vapor Carribean Islands Central America DNI GIS Mexico NREL GEF solar SWERA UNEP Data application/zip icon Download Shapefile (zip, 247.8 KiB) text/csv icon Download Data (csv, 370.6 KiB) Quality Metrics Level of Review Some Review

317

atmoshperic water vapor | OpenEI  

Open Energy Info (EERE)

atmoshperic water vapor atmoshperic water vapor Dataset Summary Description (Abstract): Monthly Average Solar Resource for flat-plate collectors tilted at latitude for China. Source NREL Date Released April 12th, 2005 (9 years ago) Date Updated October 30th, 2007 (7 years ago) Keywords atmoshperic water vapor China GEF GIS NREL solar SWERA TILT UNEP Data application/zip icon Download Shapefile (zip, 625.6 KiB) text/csv icon Download Data (csv, 704.1 KiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Time Period 01/01/1985 - 12/31/1991 License License Open Data Commons Public Domain Dedication and Licence (PDDL) Comment Rate this dataset Usefulness of the metadata Average vote Your vote Usefulness of the dataset Average vote Your vote Ease of access

318

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

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

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

319

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

DOE Green Energy (OSTI)

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

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

1994-01-01T23:59:59.000Z

320

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

Science Conference Proceedings (OSTI)

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

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

1996-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

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

SciTech Connect

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

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

1998-11-10T23:59:59.000Z

322

Thermal electric vapor trap arrangement and method  

DOE Patents (OSTI)

A technique for trapping vapor within a section of a tube is disclosed herein. This technique utilizes a conventional, readily providable thermal electric device having a hot side and a cold side and means for powering the device to accomplish this. The cold side of this device is positioned sufficiently close to a predetermined section of the tube and is made sufficiently cold so that any condensable vapor passing through the predetermined tube section is condensed and trapped, preferably within the predetermined tube section itself.

Alger, Terry (Tracy, CA)

1988-01-01T23:59:59.000Z

323

Adsorption of water vapor on reservoir rocks  

DOE Green Energy (OSTI)

Progress is reported on: adsorption of water vapor on reservoir rocks; theoretical investigation of adsorption; estimation of adsorption parameters from transient experiments; transient adsorption experiment -- salinity and noncondensible gas effects; the physics of injection of water into, transport and storage of fluids within, and production of vapor from geothermal reservoirs; injection optimization at the Geysers Geothermal Field; a model to test multiwell data interpretation for heterogeneous reservoirs; earth tide effects on downhole pressure measurements; and a finite-difference model for free surface gravity drainage well test analysis.

Not Available

1993-07-01T23:59:59.000Z

324

Method and Apparatus for Concentrating Vapors for Analysis  

DOE Patents (OSTI)

An apparatus and method are disclosed for pre-concentrating gaseous vapors for analysis. The invention finds application in conjunction with, e.g., analytical instruments where low detection limits for gaseous vapors are desirable. Vapors sorbed and concentrated within the bed of the apparatus can be thermally desorbed achieving at least partial separation of vapor mixtures. The apparatus is suitable, e.g., for preconcentration and sample injection, and provides greater resolution of peaks for vapors within vapor mixtures, yielding detection levels that are 10-10,000 times better than for direct sampling and analysis systems. Features are particularly useful for continuous unattended monitoring applications.

Grate, Jay W. (West Richland, WA); Baldwin, David L. (Kennewick, WA); Anheier, Jr., Norman C. (Richland, WA)

2008-10-07T23:59:59.000Z

325

Low Temperature Direct Growth of Graphene Films on Transparent Substrates by Chemical Vapor Deposition  

E-Print Network (OSTI)

and Few- Layer Graphene by Chemical Vapor Deposition",Liu, W. , et al. (2010). "Chemical vapor deposition of large5 1.3.3. Chemical Vapor

Antoine, Geoffrey Sandosh Jeffy

2013-01-01T23:59:59.000Z

326

FFT-LB modeling of thermal liquid-vapor systems  

E-Print Network (OSTI)

We further develop a thermal LB model for multiphase flows. In the improved model, we propose to use the FFT scheme to calculate both the convection term and external force term. The usage of FFT scheme is detailed and analyzed. By using the FFT algorithm spatiotemporal discretization errors are decreased dramatically and the conservation of total energy is much better preserved. A direct consequence of the improvement is that the unphysical spurious velocities at the interfacial regions can be damped to neglectable scale. Together with the better conservation of total energy, the more accurate flow velocities lead to the more accurate temperature field which determines the dynamical and final states of the system. With the new model, the phase diagram of the liquid-vapor system obtained from simulation is more consistent with that from theoretical calculation. Very sharp interfaces can be achieved. The accuracy of simulation results are also verified by the Laplace law. The FFT scheme can be easily applied t...

Gan, Yanbiao; Zhang, Guangcai; Li, Yingjun

2012-01-01T23:59:59.000Z

327

Measurement of gas transport properties for chemical vapor infiltration  

Science Conference Proceedings (OSTI)

In the chemical vapor infiltration (CVI) process for fabricating ceramic matrix composites (CMCs), transport of gas phase reactant into the fiber preform is a critical step. The transport can be driven by pressure or by concentration. This report describes methods for measuring this for CVI preforms and partially infiltrated composites. Results are presented for Nicalon fiber cloth layup preforms and composites, Nextel fiber braid preforms and composites, and a Nicalon fiber 3-D weave composite. The results are consistent with a percolating network model for gas transport in CVI preforms and composites. This model predicts inherent variability in local pore characteristics and transport properties, and therefore, in local densification during processing; this may lead to production of gastight composites.

Starr, T.L.; Hablutzel, N. [Georgia Inst. of Tech., Atlanta, GA (United States). School of Materials Science and Engineering

1996-12-01T23:59:59.000Z

328

Chemical vapor deposition of hydrogenated amorphous silicon from disilane  

SciTech Connect

The authors describe hydrogenated amorphous silicon (a-Si:H) thin films deposited at growth rates of 1 to 30 A/s by chemical vapor deposition (CVD) from disilane source gas at 24 torr total pressure in a tubular reactor. The effects of substrate temperature and gas holding time (flow rate) on film growth rate and effluent gas composition were measured at temperatures ranging from 360{sup 0} to 485{sup 0}C and gas holding times from 3 to 62s. Effluent gases determined by gas chromatography included silane, disilane and other higher order silanes. A chemical reaction engineering model, based on a silylene (SiH/sub 2/) insertion gas phase reaction network and film growth from both SiH/sub 2/ and high molecular weight silicon species, Si/sub n/H/sub 2n/, was developed. The model predictions were in good agreement with experimentally determined growth rates and effluent gas compositions.

Bogaert, R.J.; Russell, T.W.F.; Klein, M.T. (Delaware Univ., Newark, DE (USA). Dept. of Chemical Engineering); Rocheleau, R.E.; Baron, B.N. (Delaware Univ., Newark, DE (USA). Inst. of Energy Conversion)

1989-10-01T23:59:59.000Z

329

Low Temperature Chemical Vapor Deposition Of Thin Film Magnets  

DOE Patents (OSTI)

A thin-film magnet formed from a gas-phase reaction of tetracyanoetheylene (TCNE) OR (TCNQ), 7,7,8,8-tetracyano-P-quinodimethane, and a vanadium-containing compound such as vanadium hexcarbonyl (V(CO).sub.6) and bis(benzene)vanalium (V(C.sub.6 H.sub.6).sub.2) and a process of forming a magnetic thin film upon at least one substrate by chemical vapor deposition (CVD) at a process temperature not exceeding approximately 90.degree. C. and in the absence of a solvent. The magnetic thin film is particularly suitable for being disposed upon rigid or flexible substrates at temperatures in the range of 40.degree. C. and 70.degree. C. The present invention exhibits air-stable characteristics and qualities and is particularly suitable for providing being disposed upon a wide variety of substrates.

Miller, Joel S. (Salt Lake City, UT); Pokhodnya, Kostyantyn I. (Salt Lake City, UT)

2003-12-09T23:59:59.000Z

330

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

Science Conference Proceedings (OSTI)

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

Klein, J.

2010-12-14T23:59:59.000Z

331

METHOD FOR PRODUCING ISOTOPIC METHANES FROM LITHIUM CARBONATE AND LITHIUM HYDRIDE  

DOE Patents (OSTI)

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

Frazer, J.W.

1959-10-27T23:59:59.000Z

332

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

DOE Green Energy (OSTI)

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

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

1998-11-01T23:59:59.000Z

333

First-Principles Modeling of Hydrogen Storage in Metal Hydride Systems  

SciTech Connect

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

J. Karl Johnson

2011-05-20T23:59:59.000Z

334

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

Science Conference Proceedings (OSTI)

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

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

2008-06-08T23:59:59.000Z

335

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

DOE Green Energy (OSTI)

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

Staack, G.; Klein, J.

2011-01-20T23:59:59.000Z

336

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

DOE Green Energy (OSTI)

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

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

2011-09-01T23:59:59.000Z

337

Mechanical Behavior Studies of Depleted Uranium in the Presence of Hydrides  

DOE Green Energy (OSTI)

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

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

2011-02-14T23:59:59.000Z

338

Polynomial Fits to Saturation Vapor Pressure  

Science Conference Proceedings (OSTI)

The authors describe eighth- and sixth-order polynomial fits to Wexler's and Hyland-Wexler's saturation-vapor-pressure expressions. Fits are provided in both least-squares and relative-error norms. Error analysis is presented. The authors show ...

Piotr J. Flatau; Robert L. Walko; William R. Cotton

1992-12-01T23:59:59.000Z

339

Chemical vapor deposition of mullite coatings  

DOE Patents (OSTI)

This invention is directed to the creation of crystalline mullite coatings having uniform microstructure by chemical vapor deposition (CVD). The process comprises the steps of establishing a flow of reactants which will yield mullite in a CVD reactor, and depositing a crystalline coating from the reactant flow. The process will yield crystalline coatings which are dense and of uniform thickness.

Sarin, Vinod (Lexington, MA); Mulpuri, Rao (Boston, MA)

1998-01-01T23:59:59.000Z

340

A Water Vapor Index from Satellite Measurements  

Science Conference Proceedings (OSTI)

A method for deriving a water vapor index is presented. An important feature of the index is the fact that it does not rely on radiosondes. Thus, it is not influenced by problems associated with radiosondes and the extent to which the horizontal ...

Larry M. McMillin; David S. Crosby; Mitchell D. Goldberg

1995-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

Profiling Atmospheric Water Vapor by Microwave Radiometry  

Science Conference Proceedings (OSTI)

High-altitude microwave radiometric observations at frequencies near 92 and 183.3 GHz were used to study the potential of retrieving atmospheric water vapor profiles over both land and water. An algorithm based on an extended Kaiman-Bucy filter ...

J. R. Wang; J. L. King; T. T. Wilheit; G. Szejwach; L. H. Gesell; R. A. Nieman; D. S. Niver; B. M. Krupp; J. A. Gagliano

1983-05-01T23:59:59.000Z

342

Improved Retrieval of Integrated Water Vapor from Water Vapor Radiometer Measurements Using Numerical Weather Prediction Models  

Science Conference Proceedings (OSTI)

Water vapor radiometer (WVR) retrieval algorithms require a priori information on atmospheric conditions along the line of sight of the radiometer in order to derive opacities from observed brightness temperatures. This paper's focus is the mean ...

Steven R. Chiswell; Steven Businger; Michael Bevis; Fredrick Solheim; Christian Rocken; Randolph Ware

1994-10-01T23:59:59.000Z

343

Moisture Durability of Vapor Permeable Insulating Sheathing (Fact Sheet)  

SciTech Connect

In this project, Building America team Building Science Corporation researched some of the ramifications of using exterior, vapor permeable insulation on retrofit walls with vapor permeable cavity insulation. Retrofit strategies are a key factor in reducing exterior building stock consumption.

Not Available

2013-10-01T23:59:59.000Z

344

The Effect of vapor subcooling on film condensation of metals  

E-Print Network (OSTI)

This work presents an analysis of the interfacial "vapor-condensate" temperature distribution, which includes the effect of subcooling (supersaturation) in the vapor. Experimental data from previous investigators for ...

Fedorovich, Eugene D.

1968-01-01T23:59:59.000Z

345

Waste tank headspace gas and vapor characterization reference guide  

SciTech Connect

This document is to serve as a reference guide for gas and vapor sample results presented in tank characterization reports. It describes sampling equipment, devices, and protocols, and sample collection and analysis methods common to all vapor samples.

Huckaby, J.L.

1995-06-01T23:59:59.000Z

346

Microwave plasma chemical vapor deposition of nano-composite...  

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

plasma chemical vapor deposition of nano-composite CPt thin-films Title Microwave plasma chemical vapor deposition of nano-composite CPt thin-films Publication Type Journal...

347

Microwave Plasma Chemical Vapor Depositon of Nano-Structured...  

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

Plasma Chemical Vapor Depositon of Nano-Structured SnC Composite Thin-Film anodes for Li-ion Battteries Title Microwave Plasma Chemical Vapor Depositon of Nano-Structured SnC...

348

Estimating the Atmospheric Water Vapor Content from Sun Photometer Measurements  

Science Conference Proceedings (OSTI)

The differential absorption technique for estimating columnar water vapor values from the analysis of sunphotometric measurements with wide- and narrowband interferential filters centered near 0.94 ?m is discussed and adapted. Water vapor line ...

Artemio Plana-Fattori; Michel Legrand; Didier Tanr; Claude Devaux; Anne Vermeulen; Philippe Dubuisson

1998-08-01T23:59:59.000Z

349

Atmospheric Solar Heating Rate in the Water Vapor Bands  

Science Conference Proceedings (OSTI)

The total absorption of solar radiation by water vapor in clear atmosphere is parameterized as a simple function of the scaled water vapor amount. For applications to cloudy and hazy atmospheres, the flux-weighted k-distribution functions are ...

Ming-Dah Chou

1986-11-01T23:59:59.000Z

350

Evaluation of selected chemical processes for production of low-cost silicon (Phase II). Silicon Material Task Low-Cost Silicon Solar Array Project. Eighth quarterly progress report, July 1, 1977--September 30, 1977. [Zinc vapor reduction of silicon tetrachloride in fluidized bed of seed particles  

DOE Green Energy (OSTI)

Progress is reported in the design of a large experimental facility for the preparation of high-purity silicon by the zinc vapor reduction of silicon tetrachloride in a fluidized bed of seed particles to form a free-flowing granular product. As of July 25, 1977, the capacity goal for the experimental facility was raised from 25 to 50 MT Si/year. Process flow diagrams and materials/energy flow sheets have been revised to conform to the higher capacity and a plant layout has been developed for locating the facility within an available structure. A unit-by-unit review of instrumentation and other requirements has been made, with the inclusion of those items in the flow diagrams and flow sheets. Alternative designs are presented for a silicon carbide-coated carbon-lined fluidized-bed reactor contained in hot-wall stainless steel, including alternative designs for zinc vaporizers based on detailed heat-transfer calculations. Conditions and equipment for the conversion of by-product chlorine to hypochlorite for use in the treatment of sewage effluent locally were defined. The logistics of 19 percent NaOH delivery and pick-up of 14 percent NaOCL was worked out and equipment suppliers were identified. Heat dissipation requirements for the fluidized bed, Zn/ZnCl/sub 2/ condenser, and SiCl/sub 4/ waste disposal sections were established. Resistivity and purity data were obtained for DuPont's silicon prepared by batchwise zinc reduction of SiCl/sub 4/. A preliminary safety review was made of the experimental facility. During the report period, the miniplant was operated to (1) provide 2.2 kg of product for JPL evaluation, (2) evaluate methods of product withdrawal, and (3) test three zinc vaporizer concepts. Results of the zinc vaporizer tests were consistent with concurrent heat-transfer calculations. An average value of approximately 450 Btu hr/sup -1/ ft/sup -2/ F/sup -1/ for heat transfer from graphite to boiling zinc (1 atm) was determined.

Blocher, J.M. Jr.; Browning, M.F.; Wilson, W.J.; Carmichael, D.C.

1977-10-20T23:59:59.000Z

351

Quantitative model of vapor dominated geothermal reservoirs as heat pipes in fractured porous rock  

DOE Green Energy (OSTI)

We present a numerical model of vapor-dominated reservoirs which is based on the well-known conceptual model of White, Muffler, and Truesdell. Computer simulations show that upon heat recharge at the base, a single phase liquid-dominated geothermal reservoir in fractured rock with low matrix permeability will evolve into a two-phase reservoir with B.P.D. (boiling point-for-depth) pressure and temperature profiles. A rather limited discharge event through cracks in the caprock, involving loss of only a few percent of fluids in place, is sufficient to set the system off to evolve a vapor-dominated state. The attributes of this state are discussed, and some features requiring further clarification are identified. 26 refs., 5 figs.

Pruess, K.

1985-03-01T23:59:59.000Z

352

Metal film deposition by laser breakdown chemical vapor deposition  

Science Conference Proceedings (OSTI)

Dielectric breakdown of gas mixtures can be used to deposit homogeneous thin films by chemical vapor deposition with appropriate control of flow and pressure conditions to suppress gas phase nucleation and particle formation. Using a pulsed CO/sub 2/ laser operating at 10.6 microns where there is no significant resonant absorption in any of the source gases, we have succeeded in depositing homogeneous films from several gas phase precursors by gas phase laser pyrolysis. Nickel and molybdenum from the respective carbonyls and tungsten from the hexafluoride have been examined to date. In each case the gas precursor is buffered to reduce the partial pressure of the reactants and to induce breakdown. The films are spectrally reflective and uniform over a large area. Films have been characterized by Auger electron spectroscopy, x-ray diffraction, pull tests, and resistivity measurements. The highest quality films have resulted from the nickel depositions. Detailed x-ray diffraction analysis of these films yields a very small domain size (approx. 50 A) consistent with rapid quenching from the gas phase reaction zone. This analysis also shows nickel carbide formation consistent with the temperature of the reaction zone and the Auger electron spectroscopy results which show some carbon and oxygen incorporation (8% and 1% respectively). Gas phase transport and condensation of the molybdenum carbonyl results in substantial carbon and oxygen contamination of the molybdenum films requiring heated substrates, a requirement not consistent with the goals of the program to maximize the quench rate of the deposition. Results from tungsten deposition experiments representing a reduction chemistry instead of the decomposition chemistry involved in the carbonyl experiments are also reported.

Jervis, T.R.

1985-01-01T23:59:59.000Z

353

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

DOE Green Energy (OSTI)

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

John R. Kirkpatrick; Chris A. Dahl

2003-09-01T23:59:59.000Z

354

Modeling engine oil vaporization and transport of the oil vapor in the piston ring pack on internal combustion engines  

E-Print Network (OSTI)

A model was developed to study engine oil vaporization and oil vapor transport in the piston ring pack of internal combustion engines. With the assumption that the multi-grade oil can be modeled as a compound of several ...

Cho, Yeunwoo, 1973-

2004-01-01T23:59:59.000Z

355

Metal organic chemical vapor deposition of 111-v compounds on silicon  

DOE Patents (OSTI)

Expitaxial composite comprising thin films of a Group III-V compound semiconductor such as gallium arsenide (GaAs) or gallium aluminum arsenide (GaAlAs) on single crystal silicon substrates are disclosed. Also disclosed is a process for manufacturing, by chemical deposition from the vapor phase, epitaxial composites as above described, and to semiconductor devices based on such epitaxial composites. The composites have particular utility for use in making light sensitive solid state solar cells.

Vernon, Stanley M. (Wellesley, MA)

1986-01-01T23:59:59.000Z

356

Monolayer Graphene Growth on Ni(111) by Low Temperature Chemical Vapor Deposition  

Science Conference Proceedings (OSTI)

In contrast to the commonly employed high temperature chemical vapor deposition growth that leads to multilayer graphene formation by carbon segregation from the bulk, we demonstrate that below 600 C graphene can be grown in a self-limiting monolayer growth process. Optimum growth is achieved at {approx}550 C. Above this temperature, carbon diffusion into the bulk is limiting the surface growth rate, while at temperatures below {approx}500 C a competing surface carbide phase impedes graphene formation.

Batzill, M.; Sutter, P.; Addou, R.; Dahal, A.

2012-01-09T23:59:59.000Z

357

Advanced Membrane Systems: Recovering Wasteful and Hazardous Fuel Vapors at the Gasoline Tank  

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

Case study covering Compact Membrane Systems, Inc. and its membrane vapor processor that recovers fuel vapors from gasoline refueling.

358

Heat storage system utilizing phase change materials government rights  

DOE Patents (OSTI)

A thermal energy transport and storage system is provided which includes an evaporator containing a mixture of a first phase change material and a silica powder, and a condenser containing a second phase change material. The silica powder/PCM mixture absorbs heat energy from a source such as a solar collector such that the phase change material forms a vapor which is transported from the evaporator to the condenser, where the second phase change material melts and stores the heat energy, then releases the energy to an environmental space via a heat exchanger. The vapor is condensed to a liquid which is transported back to the evaporator. The system allows the repeated transfer of thermal energy using the heat of vaporization and condensation of the phase change material.

Salyer, Ival O. (Dayton, OH)

2000-09-12T23:59:59.000Z

359

Vapor-pressure lowering in geothermal systems  

SciTech Connect

The water vapor-pressure lowering phenomenon in porous media was investigated for a range of temperatures by measuring vapor pressure vs. mass of water adsorbed in consolidated sandstone cores and unconsolidated silica sands. Experimental results showed that the mass of water adsorbed on the rock surface is much more than the amount of pore steam. Results also revealed that the water adsorption is caused mainly by micropores in the porous medium. Measurement of the mass of methane and ethane adsorbed on dry rocks showed that the amount of adsorption is not great in comparison with the pore gas. It was found that adsorption data for water/sandstone core studies could be normalized with respect to temperature. Although this appears not to have been reported previously, it does agree in principle with findings for solid powders with micropores. Another interesting result was that reanalysis of previous studies of capillarity in sandstones indicates that experimental data probably were influenced mostly by adsorption.

Hsieh, C.H.; Ramey, H.J. Jr.

1983-02-01T23:59:59.000Z

360

Hydrocarbon pool and vapor fire data analysis  

SciTech Connect

The flame geometry and thermal radiation data from a series of large scale experiments involving liquefied petroleum gas (LPG) and gasoline spills on water were analyzed. The experiments were conducted at the Naval Weapons Center, China Lake, California. Two types of fires have been studied; namely, pool fires and vapor fires. The spill quantity varied from 4 m/sup 3/ to approximately 6 m/sup 3/. The LPG pool fire flame height to diameter ratio were between 3.5 and 4.5. The gasoline flame height was about 2. The flame emissive powers for LPG pool fires ranged from 78 kW/m/sup 2/ to 115 kW/m/sup 2/. The average surface emissive power for gasoline pool fire was 40 kW/m/sup 2/. The LPG vapor fire emissive power ranged from 159 to 269 kW/m/sup 2/. 63 figures, 13 tables.

Mudan, K.S.

1984-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

OPERATIONAL TESTS OF EBWR VAPOR RECOVERY SYSTEM  

SciTech Connect

A description of the Experimental Boiling Water Reactor vapor-recovery system is given. The seal air operating pressures, temperatures, and moisture content were measured. Air flow through the seals was measured and seal wear was assessed. Assuming direct-cycle D/sub 2/ operation, the seals were evaluated relative to the amount of D/sub 2/ leakage that would be controlled (C.J.G.)

Gariboldi, R.J.; Jacobson, D.R.

1960-08-01T23:59:59.000Z

362

Transport properties of fission product vapors  

DOE Green Energy (OSTI)

Kinetic theory of gases is used to calculate the transport properties of fission product vapors in a steam and hydrogen environment. Provided in tabular form is diffusivity of steam and hydrogen, viscosity and thermal conductivity of the gaseous mixture, and diffusivity of cesium iodide, cesium hydroxide, diatomic tellurium and tellurium dioxide. These transport properties are required in determining the thermal-hydraulics of and fission product transport in light water reactors.

Im, K.H.; Ahluwalia, R.K.

1983-07-01T23:59:59.000Z

363

Copper vapor laser modular packaging assembly  

DOE Patents (OSTI)

A modularized packaging arrangement for one or more copper vapor lasers and associated equipment is disclosed herein. This arrangement includes a single housing which contains the laser or lasers and all their associated equipment except power, water and neon, and means for bringing power, water, and neon which are necessary to the operation of the lasers into the container for use by the laser or lasers and their associated equipment.

Alger, Terry W. (Tracy, CA); Ault, Earl R. (Dublin, CA); Moses, Edward I. (Castro Valley, CA)

1992-01-01T23:59:59.000Z

364

Copper vapor laser modular packaging assembly  

DOE Patents (OSTI)

A modularized packaging arrangement for one or more copper vapor lasers and associated equipment is disclosed herein. This arrangement includes a single housing which contains the laser or lasers and all their associated equipment except power, water and neon, and means for bringing power, water, and neon which are necessary to the operation of the lasers into the container for use by the laser or lasers and their associated equipment. 2 figs.

Alger, T.W.; Ault, E.R.; Moses, E.I.

1992-12-01T23:59:59.000Z

365

DuPont Chemical Vapor Technical Report  

Science Conference Proceedings (OSTI)

DuPont Safety Resources was tasked with reviewing the current chemical vapor control practices and providing preventive recommendations on best commercial techniques to control worker exposures. The increased focus of the tank closure project to meet the 2024 Tri-Party Agreement (TPA) milestones has surfaced concerns among some CH2MHill employees and other interested parties. CH2MHill is committed to providing a safe working environment for employees and desires to safely manage the tank farm operations using appropriate control measures. To address worker concerns, CH2MHill has chartered a ''Chemical Vapors Project'' to integrate the activities of multiple CH2MHill project teams, and solicit the expertise of external resources, including an independent Industrial Hygiene expert panel, a communications consultant, and DuPont Safety Resources. Over a three-month time period, DuPont worked with CH2MHill ESH&Q, Industrial Hygiene, Engineering, and the independent expert panel to perform the assessment. The process included overview presentations, formal interviews, informal discussions, documentation review, and literature review. DuPont Safety Resources concluded that it is highly unlikely that workers in the tank farms are exposed to chemicals above established standards. Additionally, the conventional and radiological chemistry is understood, the inherent chemical hazards are known, and the risk associated with chemical vapor exposure is properly managed. The assessment highlighted management's commitment to addressing chemical vapor hazards and controlling the associated risks. Additionally, we found the Industrial Hygiene staff to be technically competent and well motivated. The tank characterization data resides in a comprehensive database containing the tank chemical compositions and relevant airborne concentrations.

MOORE, T.L.

2003-10-03T23:59:59.000Z

366

Apparatus and method for photochemical vapor deposition  

DOE Patents (OSTI)

A photochemical vapor deposition apparatus includes a reactor housing having a window in one wall above a reaction chamber in the housing. A transparent curtain divides the reaction chamber into a reaction zone and a flush zone. At least one substrate is mounted in the reaction zone in light communication with the window so that ultraviolet radiation may penetrate through the window into the reaction zone. The window is kept clear by a gas flowing through the flush zone.

Jackson, Scott C. (Wilmington, DE); Rocheleau, Richard E. (Wilmington, DE)

1987-03-31T23:59:59.000Z

367

Passive vapor transport solar heating systems  

DOE Green Energy (OSTI)

In the systems under consideration, refrigerant is evaporated in a solar collector and condensed in thermal storage for space or water heating located within the building at a level below that of the collector. Condensed liquid is lifted to an accumulator above the collector by the vapor pressure generated in the collector. Tests of two systems are described, and it is concluded that one of these systems offers distinct advantages.

Hedstrom, J.C.; Neeper, D.A.

1985-01-01T23:59:59.000Z

368

A molecular view of vapor deposited glasses  

SciTech Connect

Recently, novel organic glassy materials that exhibit remarkable stability have been prepared by vapor deposition. The thermophysical properties of these new ''stable'' glasses are equivalent to those that common glasses would exhibit after aging over periods lasting thousands of years. The origin of such enhanced stability has been elusive; in the absence of detailed models, past studies have discussed the formation of new polyamorphs or that of nanocrystals to explain the observed behavior. In this work, an atomistic molecular model of trehalose, a disaccharide of glucose, is used to examine the properties of vapor-deposited stable glasses. Consistent with experiment, the model predicts the formation of stable glasses having a higher density, a lower enthalpy, and higher onset temperatures than those of the corresponding ''ordinary'' glass formed by quenching the bulk liquid. Simulations reveal that newly formed layers of the growing vapor-deposited film exhibit greater mobility than the remainder of the material, thereby enabling a reorganization of the film as it is grown. They also reveal that ''stable'' glasses exhibit a distinct layered structure in the direction normal to the substrate that is responsible for their unusual properties.

Singh, Sadanand; Pablo, Juan J. de [Department of Chemical and Biological Engineering, University of Wisconsin, Madison Wisconsin 53706 (United States)

2011-05-21T23:59:59.000Z

369

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

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

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

370

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

DOE Green Energy (OSTI)

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

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

2011-05-26T23:59:59.000Z

371

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

DOE Green Energy (OSTI)

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

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

1988-01-01T23:59:59.000Z

372

Progress in the development of Ovonic nickel-metal hydride batteries  

SciTech Connect

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

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

1993-05-01T23:59:59.000Z

373

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

374

Magnetic properties and crystal structure of RENiA1 and UniA1 hydrides.  

DOE Green Energy (OSTI)

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

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

1999-08-11T23:59:59.000Z

375

Phase Stability, Phase Transformations, and Reactive Phase ...  

Science Conference Proceedings (OSTI)

Jul 31, 2012 ... New Phase in Stoichiometric Cu6Sn5 and Effect of Ni Addition on Phase Stabilization in Wide Temperature Range Optical Properties of...

376

Phase Diagrams  

Science Conference Proceedings (OSTI)

Mar 7, 2013 ... Computational Thermodynamics and Kinetics: Phase Diagrams ... TMS: Alloy Phases Committee, TMS: Chemistry and Physics of Materials...

377

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

DOE Green Energy (OSTI)

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

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

1976-08-01T23:59:59.000Z

378

A comparison of diamond growth rate using in-liquid and conventional plasma chemical vapor deposition methods  

Science Conference Proceedings (OSTI)

In order to make high-speed deposition of diamond effective, diamond growth rates for gas-phase microwave plasma chemical vapor deposition and in-liquid microwave plasma chemical vapor deposition are compared. A mixed gas of methane and hydrogen is used as the source gas for the gas-phase deposition, and a methanol solution of ethanol is used as the source liquid for the in-liquid deposition. The experimental system pressure is in the range of 60-150 kPa. While the growth rate of diamond increases as the pressure increases, the amount of input microwave energy per unit volume of diamond is 1 kW h/mm{sup 3} regardless of the method used. Since the in-liquid deposition method provides a superior cooling effect through the evaporation of the liquid itself, a higher electric input power can be applied to the electrodes under higher pressure environments. The growth rate of in-liquid microwave plasma chemical vapor deposition process is found to be greater than conventional gas-phase microwave plasma chemical vapor deposition process under the same pressure conditions.

Takahashi, Yoshiyuki; Toyota, Hiromichi; Nomura, Shinfuku; Mukasa, Shinobu [Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama 790-8577 (Japan); Inoue, Toru [Geodynamics Research Center, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan)

2009-06-01T23:59:59.000Z

379

Formation of amorphous metal alloys by chemical vapor deposition  

SciTech Connect

Amorphous alloys are deposited by a process of thermal dissociation of mixtures or organometallic compounds and metalloid hydrides, e.g., transition metal carbonyl such as nickel carbonyl, and diborane. Various sizes and shapes of deposits can be achieved, including near-net-shape free standing articles, multilayer deposits, and the like. Manipulation or absence of a magnetic field affects the nature and the structure of the deposit.

Mullendore, Arthur W. (Sandia Park, NM)

1990-01-01T23:59:59.000Z

380

A ghost fluid method for compressible reacting flows with phase change  

Science Conference Proceedings (OSTI)

A modified interfacial Riemann problem accounting for phase change and surface tension was developed to couple a reacting gas to a vaporizing compressible liquid. Results from the proposed numerical method compare well with empirically measured separation ... Keywords: Chemically reacting flow, Compressible multiphase flow, Ghost fluid method, Level set method, Navier-Stokes equations, Vaporization

Ryan W. Houim; Kenneth K. Kuo

2013-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

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

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

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

382

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

E-Print Network (OSTI)

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

Sames, William

2011-05-01T23:59:59.000Z

383

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

384

Vapor port and groundwater sampling well  

DOE Patents (OSTI)

A method and apparatus have been developed for combining groundwater monitoring wells with unsaturated-zone vapor sampling ports. The apparatus allows concurrent monitoring of both the unsaturated and the saturated zone from the same well at contaminated areas. The innovative well design allows for concurrent sampling of groundwater and volatile organic compounds (VOCs) in the vadose (unsaturated) zone from a single well, saving considerable time and money. The sample tubes are banded to the outer well casing during installation of the well casing. 10 figs.

Hubbell, J.M.; Wylie, A.H.

1996-01-09T23:59:59.000Z

385

Vapor port and groundwater sampling well  

DOE Patents (OSTI)

A method and apparatus has been developed for combining groundwater monitoring wells with unsaturated-zone vapor sampling ports. The apparatus allows concurrent monitoring of both the unsaturated and the saturated zone from the same well at contaminated areas. The innovative well design allows for concurrent sampling of groundwater and volatile organic compounds (VOCs) in the vadose (unsaturated) zone from a single well, saving considerable time and money. The sample tubes are banded to the outer well casing during installation of the well casing.

Hubbell, Joel M. (Idaho Falls, ID); Wylie, Allan H. (Idaho Falls, ID)

1996-01-01T23:59:59.000Z

386

Copper vapor laser acoustic thermometry system  

DOE Patents (OSTI)

A copper vapor laser (CVL) acoustic thermometry system is disclosed. The invention couples an acoustic pulse a predetermined distance into a laser tube by means of a transducer and an alumina rod such that an echo pulse is returned along the alumina rod to the point of entry. The time differential between the point of entry of the acoustic pulse into the laser tube and the exit of the echo pulse is related to the temperature at the predetermined distance within the laser tube. This information is processed and can provide an accurate indication of the average temperature within the laser tube.

Galkowski, J.J.

1986-08-27T23:59:59.000Z

387

Photochemical studies of alkali halide vapors  

SciTech Connect

Thesis. An apparatus has been constructed for studying the photodissociation of alkali halides to produce excited alkali metal atoms. The key component is a low pressure H/sub 2/ arc continuum uv source. Radiation from this source, modulated by a chopping wheel and analyzed by a monochromator, enters a cell containing the alkali halide vapor. In the appropriate wavelength range, photodissociation occurs to produce the alkali atom in an excited /sup 2/p state, the flourescence from which is detected by a photomultiplier-lock-in amplifier combination. (auth)

Earl, B.L.

1973-08-01T23:59:59.000Z

388

ARM - Field Campaign - Fall 1997 Water Vapor IOP  

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

Water Vapor IOP Water Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Fall 1997 Water Vapor IOP 1997.09.15 - 1997.10.05 Lead Scientist : Henry Revercomb For data sets, see below. Summary The Water Vapor IOP was conducted as a follow-up to a predecessor IOP on water vapor held in September 1996. This IOP relied heavily on both ground-based guest and CART instrumentation and in-situ aircraft and tethered sonde/kite measurements. Primary operational hours were from 6 p.m. Central until at least midnight, with aircraft support normally from about 9 p.m. until midnight when available. However, many daytime measurements were made to support this IOP. The first Water Vapor IOP primarily concentrated on the atmosphere's lowest

389

Method and apparatus for concentrating vapors for analysis  

DOE Patents (OSTI)

A pre-concentration device and a method are disclosed for concentrating gaseous vapors for analysis. Vapors sorbed and concentrated within the bed of the pre-concentration device are thermally desorbed, achieving at least partial separation of the vapor mixtures. The pre-concentration device is suitable, e.g., for pre-concentration and sample injection, and provides greater resolution of peaks for vapors within vapor mixtures, yielding detection levels that are 10-10,000 times better than direct sampling and analysis systems. Features are particularly useful for continuous unattended monitoring applications. The invention finds application in conjunction with, e.g., analytical instruments where low detection limits for gaseous vapors are desirable.

Grate, Jay W. (West Richland, WA); Baldwin, David L. (Kennewick, WA); Anheier, Jr., Norman C. (Richland, WA)

2012-06-05T23:59:59.000Z

390

Analysis of the transient compressible vapor flow in heat pipe  

SciTech Connect

The transient compressible one-dimensional vapor flow dynamics in a heat pipe is modeled. The numerical results are obtained by using the implicit non-iterative Beam-Warming finite difference method. The model is tested for simulated heat pipe vapor flow and actual vapor flow in cylindrical heat pipes. A good comparison of the present transient results for the simulated heat pipe vapor flow with the previous results of a two-dimensional numerical model is achieved and the steady state results are in agreement with the existing experimental data. The transient behavior of the vapor flow under subsonic, sonic, and supersonic speeds and high mass flow rates are successfully predicted. The one-dimensional model also describes the vapor flow dynamics in cylindrical heat pipes at high temperatures.

Jang, J.H.; Faghri, A. [Wright State Univ., Dayton, OH (United States); Chang, W.S. [Wright Research and Development Center, Wright-Patterson, OH (United States)

1989-07-01T23:59:59.000Z

391

Water injection as a means for reducing non-condensible andcorrosive gases in steam produced from vapor-dominated reservoirs  

Science Conference Proceedings (OSTI)

Large-scale water injection at The Geysers, California, hasgenerated substantial benefits in terms of sustaining reservoir pressuresand production rates, as well as improving steam composition by reducingthe content of non-condensible gases (NCGs). Two effects have beenrecognized and discussed in the literature as contributing to improvedsteam composition, (1) boiling of injectate provides a source of "clean"steam to production wells, and (2) pressurization effects induced byboiling of injected water reduce upflow of native steam with large NCGconcentrations from depth. In this paper we focus on a possibleadditional effect that could reduce NCGs in produced steam by dissolutionin a condensed aqueous phase.Boiling of injectate causes pressurizationeffects that will fairly rapidly migrate outward, away from the injectionpoint. Pressure increases will cause an increase in the saturation ofcondensed phase due to vapor adsorption on mineral surfaces, andcapillary condensation in small pores. NCGs will dissolve in theadditional condensed phase which, depending upon their solubility, mayreduce NCG concentrations in residual steam.We have analyzed thepartitioning of HCl between vapor and aqueous phases, and have performednumerical simulations of injection into superheated vapor zones. Oursimulations provide evidence that dissolution in the condensed phase canindeed reduce NCG concentrations in produced steam.

Pruess, Karsten; Spycher, Nicolas; Kneafsey, Timothy J.

2007-01-08T23:59:59.000Z

392

Effects of capillary heterogeneity on vapor-liquid counterflow in porous media  

DOE Green Energy (OSTI)

Based on a continuum description, the effect of capillary heterogeneity, induced by variation in permeability, on the steady state, countercurrent, vapor-liquid flow in porous media is analyzed. It is shown that the heterogeneity acts as a body force, that may enhance or diminish gravity effects on heat pipes. Selection rules that determine the steady states reached in homogeneous, gravity-driven heat pipes are also formulated. It is shown that the ``infinite`` two-phase zone may terminate by a substantial change in the permeability somewhere in the medium. The two possible sequences, liquid - liquid dominated - dry, or liquid - vapor dominated - dry find applications in geothermal systems. Finally, it is shown that although weak heterogeneity affects only gravity controlled flows, stronger variations in permeability can give rise to significant capillary effects.

Stubos, A.K.; Satik, C.; Yortsos, Y.C.

1992-06-01T23:59:59.000Z

393

Effects of capillary heterogeneity on vapor-liquid counterflow in porous media  

DOE Green Energy (OSTI)

Based on a continuum description, the effect of capillary heterogeneity, induced by variation in permeability, on the steady state, countercurrent, vapor-liquid flow in porous media is analyzed. It is shown that the heterogeneity acts as a body force, that may enhance or diminish gravity effects on heat pipes. Selection rules that determine the steady states reached in homogeneous, gravity-driven heat pipes are also formulated. It is shown that the infinite'' two-phase zone may terminate by a substantial change in the permeability somewhere in the medium. The two possible sequences, liquid - liquid dominated - dry, or liquid - vapor dominated - dry find applications in geothermal systems. Finally, it is shown that although weak heterogeneity affects only gravity controlled flows, stronger variations in permeability can give rise to significant capillary effects.

Stubos, A.K.; Satik, C.; Yortsos, Y.C.

1992-06-01T23:59:59.000Z

394

Method for controlling corrosion in thermal vapor injection gases  

DOE Patents (OSTI)

An improvement in the method for producing high pressure thermal vapor streams from combustion gases for injection into subterranean oil producing formations to stimulate the production of viscous minerals is described. The improvement involves controlling corrosion in such thermal vapor gases by injecting water near the flame in the combustion zone and injecting ammonia into a vapor producing vessel to contact the combustion gases exiting the combustion chamber.

Sperry, John S. (Houston, TX); Krajicek, Richard W. (Houston, TX)

1981-01-01T23:59:59.000Z

395

Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) | Open Energy  

Open Energy Info (EERE)

Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) Exploration Activity Details Location Haleakala Volcano Area Exploration Technique Mercury Vapor Activity Date Usefulness not indicated DOE-funding Unknown Notes The field survey program on the northwest rift zone consisted of soil mercury and radon emanometry surveys, groundwater temperature and chemistry studies, Schlumberger resistivity soundings and self-potential profiles. Geophysical and geochemical surveys along this rift (southwest) were limited by difficult field conditions and access limitations. The geophysical program consisted of one Schlumberger sounding, one

396

Mercury Vapor At Lassen Volcanic National Park Area (Varekamp...  

Open Energy Info (EERE)

Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon Mercury Vapor At Lassen Volcanic National Park Area (Varekamp & Buseck, 1983) Jump to:...

397

Mercury Vapor At Mickey Hot Springs Area (Varekamp & Buseck,...  

Open Energy Info (EERE)

Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon Mercury Vapor At Mickey Hot Springs Area (Varekamp & Buseck, 1983) Jump to: navigation,...

398

Mercury Vapor At Breitenbush Hot Springs Area (Varekamp & Buseck...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Breitenbush Hot Springs Area (Varekamp & Buseck, 1983) Exploration Activity...

399

Mercury Vapor At Vale Hot Springs Area (Varekamp & Buseck, 1983...  

Open Energy Info (EERE)

Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon Mercury Vapor At Vale Hot Springs Area (Varekamp & Buseck, 1983) Jump to: navigation, search...

400

Interaction of sodium vapor and graphite studied by ...  

Science Conference Proceedings (OSTI)

The kinetics of the reaction between graphite and sodium vapor is analyzed with support ... High temperature compression test to determine the anode paste...

Note: This page contains sample records for the topic "hydride vapor phase" 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

Optimal Control of Vapor Extraction of Heavy Oil.  

E-Print Network (OSTI)

??Vapor extraction (Vapex) process is an emerging technology for viscous oil recovery that has gained much attention in the oil industry. However, the oil production (more)

Muhamad, Hameed

2012-01-01T23:59:59.000Z

402

ARM - Field Campaign - ARM-FIRE Water Vapor Experiment  

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

Order Data Browell, Edward LASE Order Data Gutman, Seth GPS Order Data Richardson, Scott Chilled Mirror Order Data Sachse, G. Water Vapor Order Data Schmidlin, Francis CM Sondes...

403

Measurements of Vapor Pressures and PVT Properties for n ...  

Science Conference Proceedings (OSTI)

Page 1. Measurements of Vapor Pressures and PVT Properties for n-Butane from 280 to 440 K at Pressures to 200 MPa ...

2006-07-20T23:59:59.000Z

404

Molecular restrictions for human eye irritation by chemical vapors  

E-Print Network (OSTI)

and reactive airborne chemicals. Pharmacol. Toxicol. 1998;WL. Chemesthesis: The Common Chemical Sense. In: Finger TE,MH. Quantification of chemical vapors in chemosensory

Cometto-Muniz, J. Enrique; Cain, William S.; Abraham, Michael H.

2005-01-01T23:59:59.000Z

405

Raman Lidar Measurements of Aerosols and Water Vapor During the...  

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

Raman Lidar Measurements of Aerosols and Water Vapor During the May 2003 Aerosol IOP R. A. Ferrare National Aeronautics and Space Administration Langley Research Center Hampton,...

406

Cesium vapor cycle for an advanced LMFBR  

SciTech Connect

A review indicates that a cesium vapor topping cycle appears attractive for use in the intermediate fluid circuit of an advanced LMFBR designed for a reactor outlet temperature of 1250$sup 0$F or more and would have the following advantages: (1) it would increase the thermal efficiency by about 5 to 10 points (from approximately 40 percent to approximately 45 to 50 percent) thus reducing the amount of waste heat rejected to the environment by 15 to 30 percent. (2) the higher thermal efficiency should reduce the overall capital cost of the reactor plant in dollars per kilowatt. (3) the cesium can be distilled out of the intermediate fluid circuit to leave it bone-dry, thus greatly reducing the time and cost of maintenance work (particularly for the steam generator). (4) the large volume and low pressure of the cesium vapor region in the cesium condenser-steam generator greatly reduces the magnitude of pressure fluctuations that might occur in the event of a leak in a steam generator tube, and the characteristics inherent in a condenser make it easy to design for rapid concentration of any noncondensibles that may form as a consequence of a steam leak into the cesium region so that a steam leak can be detected easily in the very early stages of its development. (auth)

Fraas, A.P.

1975-01-01T23:59:59.000Z

407

Reactions of atmospheric vapors with lunar soil  

SciTech Connect

Detailed experimental data have been acquired for the hydration of the surfaces of lunar fines. Inert vapor adsorption has been employed to measure the surface properties (surface energy, surface area, porosity, etc.) and changes wrought in the hydration-dehydration processes. Plausible mechanisms have been considered and the predominant process involves hydration of the metamict metallosilicate surfaces to form a hydrated laminar structure akin to terrestrial clays. Additional credence for this interpretation is obtained by comparison to existing geochemical literature concerning terrestrial weathering of primary metallosilicates. The surface properties of the hydrated lunar fines are compared favorably to those of terrestrial clay minerals. In addition, experimental results are given to show that fresh disordered surfaces of volcanic sand react with water vapor in a manner virtually identical to the majority of the lunar fines. The results show that ion track etching and/or grain boundary attack are minor contributions in the weathering of lunar fines in the realm of our microgravimetric experimental conditions. 14 references. (auth)

Fuller, E.L. Jr.; Agron, P.A.

1976-03-01T23:59:59.000Z

408

Phase five  

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

Phase five Phase five 1663 Los Alamos science and technology magazine Latest Issue:November 2013 All Issues » submit Phase five Los Alamos physicists have conclusively demonstrated the existence of a new phase of matter. November 25, 2013 Phase five Scientists still have more to learn about the exotic physics of specialty materials. What makes the cuprates special? How about a new phase of matter. Ceramic metals known as cuprates have mystified physicists for decades. They exhibit a variety of distinct phases of matter, each with its own specific properties, including a phase bearing an exotic type of magnetism, a high-temperature superconducting phase, an ordinary metal phase, a poorly understood and weird metallic phase simply called a strange metal, and an equally poorly understood metallic phase known as the pseudogap. The

409

Integration of Global Positioning System and Scanning Water Vapor Radiometers for Precipitable Water Vapor and Cloud Liquid Path Estimates  

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

Integration of Global Positioning System and Scanning Integration of Global Positioning System and Scanning Water Vapor Radiometers for Precipitable Water Vapor and Cloud Liquid Path Estimates V. Mattioli and P. Basili Department of Electronic and Information Engineering University of Perugia Perugia, Italy E. R. Westwater Cooperative Institute for Research in Environmental Sciences University of Colorado National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado Introduction In recent years the Global Positioning System (GPS) has proved to be a reliable instrument for measuring precipitable water vapor (PWV) (Bevis et al. 1992), offering an independent source of information on water vapor when compared with microwave radiometers (MWRs), and/or radiosonde

410

Vapor and gas sampling of Single-Shell Tank 241-A-101 using the Vapor Sampling System  

Science Conference Proceedings (OSTI)

This document presents sampling data resulting from the June 8, 1995, sampling of SST 241-A-101 using the Vapor Sampling System.

Caprio, G.S.

1995-11-01T23:59:59.000Z

411

Vapor and gas sampling of single-shell tank 241-SX-106 using the vapor sampling system  

SciTech Connect

This document presents sampling data resulting from the March 24, 1995, sampling of SST 241-SX-106 using the vapor sampling system.

Caprio, G.S.

1995-09-20T23:59:59.000Z

412

Thermodynamics Resource: Gas-Phase Database and the Condensed-Phase Data File  

DOE Data Explorer (OSTI)

The Thermodynamics Resource provides thermochemistry for gas-phase and condensed species relevant to a wide range of high-temperature processes, including chemical vapor deposition (CVD), chemical vapor infiltration (CVI), catalysis, combustion, materials corrosion, and aerosol processing. Thermochemistry is the foundation for understanding chemical reactions and as such is essential to the development of predictive models for many high-temperature processes. The database includes thermodynamic data (heats of formation, enthalpies, entropies, and heat capacities) for gas and condensed-phase species, thermodynamic models for specific condensed-phase material systems that account for non-ideal behavior in those systems, and a wide range of calculated molecular properties for gas-phase species. (Specialized Interface)

Allendorf, Mark D.; Besmann, Theodore M.

413

The Water Vapor Abundance in Orion KL Outflows  

E-Print Network (OSTI)

We present the detection and modeling of more than 70 far-IR pure rotational lines of water vapor, including the 18O and 17O isotopologues, towards Orion KL. Observations were performed with the Long Wavelength Spectrometer Fabry-Perot (LWS/FP; R~6800-9700) on board the Infrared Space Observatory (ISO) between ~43 and ~197 um. The water line profiles evolve from P-Cygni type profiles (even for the H2O18 lines) to pure emission at wavelengths above ~100 um. We find that most of the water emission/absorption arises from an extended flow of gas expanding at 25+-5 kms^-1. Non-local radiative transfer models show that much of the water excitation and line profile formation is driven by the dust continuum emission. The derived beam averaged water abundance is 2-3x10^-5. The inferred gas temperature Tk=80-100 K suggests that: (i) water could have been formed in the "plateau" by gas phase neutral-neutral reactions with activation barriers if the gas was previously heated (e.g. by shocks) to >500 K and/or (ii) H2O formation in the outflow is dominated by in-situ evaporation of grain water-ice mantles and/or (iii) H2O was formed in the innermost and warmer regions (e.g. the hot core) and was swept up in ~1000 yr, the dynamical timescale of the outflow.

J. Cernicharo; J. R. Goicoechea; F. Daniel; M. R. Lerate; M. J. Barlow; B. M. Swinyard; E. van Dishoeck; T. L. Lim; S. Viti; J. Yates

2006-08-16T23:59:59.000Z

414

FFT-LB modeling of thermal liquid-vapor systems  

E-Print Network (OSTI)

We further develop a thermal LB model for multiphase flows. In the improved model, we propose to use the FFT scheme to calculate both the convection term and external force term. The usage of FFT scheme is detailed and analyzed. By using the FFT algorithm spatiotemporal discretization errors are decreased dramatically and the conservation of total energy is much better preserved. A direct consequence of the improvement is that the unphysical spurious velocities at the interfacial regions can be damped to neglectable scale. Together with the better conservation of total energy, the more accurate flow velocities lead to the more accurate temperature field which determines the dynamical and final states of the system. With the new model, the phase diagram of the liquid-vapor system obtained from simulation is more consistent with that from theoretical calculation. Very sharp interfaces can be achieved. The accuracy of simulation results are also verified by the Laplace law. The FFT scheme can be easily applied to other models for multiphase flows.

Yanbiao Gan; Aiguo Xu; Guangcai Zhang; Yingjun Li

2010-11-16T23:59:59.000Z

415

Chemical vapor deposition of amorphous silicon films from disilane  

SciTech Connect

Amorphous silicon films for fabrication of solar cells have been deposited by thermal chemical vapor deposition (CVD) from disilane (Si/sub 2/H/sub 6/) using a tubular flow reactor. A mathematical description for the CVD reactor was developed and solved by a numerical procedure. The proposed chemical reaction network for the model is based on silylene (SiH/sub 2/) insertion in the gas phase and film growth from SiH/sub 2/ and silicon polymers (Si/sub n/N/sub 2n/, n approx. 10). Estimates of the rate constants have been obtained for trisilane decomposition, silicon polymer formation, and polymer dehydrogenation. The silane unimolecular decomposition rate constants were corrected for pressure effects. The model behavior is compared to the experimental results over the range of conditions: reactor temperature (360 to 485/sup 0/C), pressures (2 to 48 torr), and gas holding time (1 to 70 s). Within the above range of conditions, film growth rate varies from 0.01 to 30 A/s. Results indicate that silicon polymers are the main film precursors for gas holding times greater than 3 s. Film growth by silylene only becomes important at short holding times, large inert gas dilution, and positions near the beginning of the reactor hot zone.

Bogaert, R.J.

1986-01-01T23:59:59.000Z

416

Phase equilibrium studies  

DOE Green Energy (OSTI)

A phase equilibrium model has been developed for the SRC-I process, as well as the other coal liquefaction processes. It is applicable to both vapor/liquid and liquid/liquid equilibria; it also provides an approximate but adequate description of aqueous mixtures where the volatile electrolyte components dissociate to form ionic species. This report completes the description of the model presented in an earlier report (Mathias and Stein, 1983a). Comparisons of the model to previously published data on coal-fluid mixtures are presented. Further, a preliminary analysis of new data on SRC-I coal fluids is presented. Finally, the current capabilities and deficiencies of the model are discussed. 25 references, 17 figures, 30 tables.

Mathias, P.M.; Stein, F.P.

1983-09-01T23:59:59.000Z

417

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

DOE Green Energy (OSTI)

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

Peterman, D.J.

1980-01-01T23:59:59.000Z

418

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

Science Conference Proceedings (OSTI)

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

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

1999-10-01T23:59:59.000Z

419

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

DOE Green Energy (OSTI)

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

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

1994-11-01T23:59:59.000Z

420

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

Science Conference Proceedings (OSTI)

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

Majzoub, Eric H.; Ronnebro, Ewa

2012-02-22T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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

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

Science Conference Proceedings (OSTI)

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

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

2011-10-05T23:59:59.000Z

422

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

DOE Green Energy (OSTI)

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

Lim, Hong S.

1996-03-01T23:59:59.000Z

423

FLAMMABILITY CHARACTERISTICS OF COMBUSTIBLE GASES AND VAPORS  

Office of Scientific and Technical Information (OSTI)

Bulletin 627 Bulletin 627 BUREAU o b MINES FLAMMABILITY CHARACTERISTICS OF COMBUSTIBLE GASES AND VAPORS By Michael G. Zabetakis DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency Thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement,

424

New Regenerative Cycle for Vapor Compression Refrigeration  

Office of Scientific and Technical Information (OSTI)

SCIENTIFIC REPORT SCIENTIFIC REPORT Title Page Project Title: New Regenerative Cycle for Vapor Compression Refrigeration DOE Award Number: DE-FG36-04GO14327 Document Title: Final Scientific Report Period Covered by Report: September 30, 2004 to September 30, 2005 Name and Address of Recipient Organization: Magnetic Development, Inc., 68 Winterhill Road, Madison, CT 06443, phone: 203-214-7247, fax: 203-421-7948, e-mail: mjb1000@aol.com Contact Information: Mark J. Bergander, Ph.D., P.E., Principal Investigator, phone: 203-214-7247, fax: 203-421-7948, e-mail: mjb1000@aol.com Project Objective (as stated in the proposal): The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient

425

Gas transport model for chemical vapor infiltration  

Science Conference Proceedings (OSTI)

A node-bond percolation model is presented for the gas permeability and pore surface area of the coarse porosity in woven fiber structures during densification by chemical vapor infiltration (CVI). Model parameters include the number of nodes per unit volume and their spatial distribution, and the node and bond radii and their variability. These parameters relate directly to structural features of the weave. Some uncertainty exists in the proper partition of the porosity between ``node`` and ``bond`` and between intra-tow and inter-tow, although the total is constrained by the known fiber loading in the structure. Applied to cloth layup preforms the model gives good agreement with the limited number of available measurements.

Starr, T.L. [School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245 (United States)

1995-09-01T23:59:59.000Z

426

RESONANT FARADAY ROTATION IN A HOT LITHIUM VAPOR  

E-Print Network (OSTI)

RESONANT FARADAY ROTATION IN A HOT LITHIUM VAPOR By SCOTT RUSSELL WAITUKAITIS A Thesis Submitted: #12;Abstract I describe a study of Faraday rotation in a hot lithium vapor. I begin by dis- cussing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 The Lithium Oven and Solenoid . . . . . . . . . . . . . . . . . 7 3 Theoretical Framework

Cronin, Alex D.

427

Hybrid Vapor Compression Adsorption System: Thermal Storage Using Hybrid Vapor Compression Adsorption System  

SciTech Connect

HEATS Project: UTRC is developing a new climate-control system for EVs that uses a hybrid vapor compression adsorption system with thermal energy storage. The targeted, closed system will use energy during the battery-charging step to recharge the thermal storage, and it will use minimal power to provide cooling or heating to the cabin during a drive cycle. The team will use a unique approach of absorbing a refrigerant on a metal salt, which will create a lightweight, high-energy-density refrigerant. This unique working pair can operate indefinitely as a traditional vapor compression heat pump using electrical energy, if desired. The project will deliver a hot-and-cold battery that provides comfort to the passengers using minimal power, substantially extending the driving range of EVs.

None

2012-01-04T23:59:59.000Z

428

Physicochemical Perturbations of Phase Equilibriums  

E-Print Network (OSTI)

The alternative approach to the displacement of gas/liquid equilibrium is developed on the basis of the Clapeyron equation. The phase transition in the system with well-established properties is taken as a reference process to search for the parameters of phase transition in the perturbed equilibrium system. The main equation, derived in the framework of both classical thermodynamics and statistical mechanics, establishes a correlation between variations of enthalpies of evaporation, \\Delta (\\Delta H), which is induced by perturbations, and the equilibrium vapor pressures. The dissolution of a solute, changing the surface shape, and the effect of the external field of adsorbents are considered as the perturbing actions on the liquid phase. The model provides the unified method for studying (1) solutions, (2) membrane separations (3) surface phenomena, and (4) effect of the adsorption field; it leads to the useful relations between \\Delta (\\Delta H), on the one hand, and the osmotic pressures, the Donnan poten...

Dobruskin, Vladimir Kh

2010-01-01T23:59:59.000Z

429

Worker Protection from Chemical Vapors: Hanford Tank Farms  

Science Conference Proceedings (OSTI)

Chemical vapor emissions from underground hazardous waste storage tanks on the Hanford site in eastern Washington State are a potential concern because workers enter the tank farms on a regular basis for waste retrievals, equipment maintenance, and surveillance. Tank farm contractors are in the process of retrieving all remaining waste from aging single-shell tanks, some of which date to World War II, and transferring it to newer double-shell tanks. During the waste retrieval process, tank farm workers are potentially exposed to fugitive chemical vapors that can escape from tank head-spaces and other emission points. The tanks are known to hold more than 1,500 different species of chemicals, in addition to radionuclides. Exposure assessments have fully characterized the hazards from chemical vapors in half of the tank farms. Extensive sampling and analysis has been done to characterize the chemical properties of hazardous waste and to evaluate potential health hazards of vapors at the ground surface, where workers perform maintenance and waste transfer activities. Worker concerns, risk communication, and exposure assessment are discussed, including evaluation of the potential hazards of complex mixtures of chemical vapors. Concentrations of vapors above occupational exposure limits (OEL) were detected only at exhaust stacks and passive breather filter outlets. Beyond five feet from the sources, vapors disperse rapidly. No vapors have been measured above 50% of their OELs more than five feet from the source. Vapor controls are focused on limited hazard zones around sources. Further evaluations of vapors include analysis of routes of exposure and thorough analysis of nuisance odors. (authors)

Anderson, T.J. [CH2M HILL Hanford Group, Inc. / Environmental Health, Richland, WA (United States)

2007-07-01T23:59:59.000Z

430

The Effects of Water Vapor on the Oxidation of Nickel-Base ...  

Science Conference Proceedings (OSTI)

water vapor are compared at temperatures from 700C to 1100C. It is shown that water vapor affects the oxidation of such alloys in different ways. Water vapor...

431

Water Vapor Flux Measurements from Ground-Based Vertically Pointed Water Vapor Differential Absorption and Doppler Lidars  

Science Conference Proceedings (OSTI)

For the first time, two lidar systems were used to measure the vertical water vapor flux in a convective boundary layer by means of eddy correlation. This was achieved by combining a water vapor differential absorption lidar and a heterodyne wind ...

Andreas Giez; Gerhard Ehret; Ronald L. Schwiesow; Kenneth J. Davis; Donald H. Lenschow

1999-02-01T23:59:59.000Z

432

Thermal Design of an Ultrahigh Temperature Vapor Core Reactor Combined Cycle Nuclear Power Plant  

SciTech Connect

Current work modeling high temperature compact heat exchangers may demonstrate the design feasibility of a Vapor Core Reactor (VCR) driven combined cycle power plant. For solid nuclear fuel designs, the cycle efficiency is typically limited by a metallurgical temperature limit which is dictated by fuel and structural melting points. In a vapor core, the gas/vapor phase nuclear fuel is uniformly mixed with the topping cycle working fluid. Heat is generated homogeneously throughout the working fluid thus extending the metallurgical temperature limit. Because of the high temperature, magnetohydrodynamic (MHD) generation is employed for topping cycle power extraction. MHD rejected heat is transported via compact heat exchanger to a conventional Brayton gas turbine bottoming cycle. High bottoming cycle mass flow rates are required to remove the waste heat because of low heat capacities for the bottoming cycle gas. High mass flow is also necessary to balance the high Uranium Tetrafluoride (UF{sub 4}) mass flow rate in the topping cycle. Heat exchanger design is critical due to the high temperatures and corrosive influence of fluoride compounds and fission products existing in VCR/MHD exhaust. Working fluid compositions for the topping cycle include variations of Uranium Tetrafluoride, Helium and various electrical conductivity seeds for the MHD. Bottoming cycle working fluid compositions include variations of Helium and Xenon. Some thought has been given to include liquid metal vapor in the bottoming cycle for a Cheng or evaporative cooled design enhancement. The NASA Glenn Lewis Research Center code Chemical Equilibrium with Applications (CEA) is utilized for evaluating chemical species existing in the gas stream. Work being conducted demonstrates the compact heat exchanger design, utilization of the CEA code, and assessment of different topping and bottoming working fluid compositions. (authors)

Bays, Samuel E.; Anghaie, Samim; Smith, Blair; Knight, Travis [Innovative Space Power and Propulsion Institute, University of Florida, 202 Nuclear Science Building, Gainesville, FL 32611 (United States)

2004-07-01T23:59:59.000Z

433

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

Science Conference Proceedings (OSTI)

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

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

2009-08-01T23:59:59.000Z

434

Mercury Vapor At Silver Peak Area (Henkle, Et Al., 2005) | Open...  

Open Energy Info (EERE)

Mercury Vapor At Silver Peak Area (Henkle, Et Al., 2005) Exploration Activity Details Location Silver Peak Area Exploration Technique Mercury Vapor Activity Date Usefulness useful...

435

Does EIA report water vapor emissions data? - FAQ - U.S. Energy ...  

U.S. Energy Information Administration (EIA)

Does EIA report water vapor emissions data? No. Water vapor is the most abundant greenhouse gas, but most scientists believe that human activity has a very small ...

436

EA-0881: Tank 241-c-103 Organic Vapor and Liquid Characterization...  

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

881: Tank 241-c-103 Organic Vapor and Liquid Characterization and Supporting Activities, Hanford Site, Richland, Washington EA-0881: Tank 241-c-103 Organic Vapor and Liquid...

437

Enhanced Attenuation Technologies: Passive Soil Vapor Extraction  

SciTech Connect

Passive soil vapor extraction (PSVE) is an enhanced attenuation (EA) approach that removes volatile contaminants from soil. The extraction is driven by natural pressure gradients between the subsurface and atmosphere (Barometric Pumping), or by renewable sources of energy such as wind or solar power (Assisted PSVE). The technology is applicable for remediating sites with low levels of contamination and for transitioning sites from active source technologies such as active soil vapor extraction (ASVE) to natural attenuation. PSVE systems are simple to design and operate and are more cost effective than active systems in many scenarios. Thus, PSVE is often appropriate as an interim-remedial or polishing strategy. Over the past decade, PSVE has been demonstrated in the U.S. and in Europe. These demonstrations provide practical information to assist in selecting, designing and implementing the technology. These demonstrations indicate that the technology can be effective in achieving remedial objectives in a timely fashion. The keys to success include: (1) Application at sites where the residual source quantities, and associated fluxes to groundwater, are relatively low; (2) Selection of the appropriate passive energy source - barometric pumping in cases with a deep vadose zone and barrier (e.g., clay) layers that separate the subsurface from the atmosphere and renewable energy assisted PSVE in other settings and where higher flow rates are required. (3) Provision of sufficient access to the contaminated vadose zones through the spacing and number of extraction wells. This PSVE technology report provides a summary of the relevant technical background, real-world case study performance, key design and cost considerations, and a scenario-based cost evaluation. The key design and cost considerations are organized into a flowchart that dovetails with the Enhanced Attenuation: Chlorinated Organics Guidance of the Interstate Technology and Regulatory Council (ITRC). The PSVE flowchart provides a structured process to determine if the technology is, or is not, reasonable and defensible for a particular site. The central basis for that decision is the expected performance of PSVE under the site specific conditions. Will PSVE have sufficient mass removal rates to reduce the release, or flux, of contamination into the underlying groundwater so that the site can meet it overall remedial objectives? The summary technical information, case study experiences, and structured decision process provided in this 'user guide' should assist environmental decision-makers, regulators, and engineers in selecting and successfully implementing PSVE at appropriate sites.

Vangelas, K.; Looney, B.; Kamath, R.; Adamson, D.; Newell, C.

2010-03-15T23:59:59.000Z

438

Desalination Using Vapor-Compression Distillation  

E-Print Network (OSTI)

The ability to produce potable water economically is the primary purpose of seawater desalination research. Reverse osmosis (RO) and multi-stage flash (MSF) cost more than potable water produced from fresh water resources. As an alternative to RO and MSF, this research investigates a high-efficiency mechanical vapor-compression distillation system that employs an improved water flow arrangement. The incoming salt concentration was 0.15% salt for brackish water and 3.5% salt for seawater, whereas the outgoing salt concentration was 1.5% and 7%, respectively. Distillation was performed at 439 K (331oF) and 722 kPa (105 psia) for both brackish water feed and seawater feed. Water costs of the various conditions were calculated for brackish water and seawater feeds using optimum conditions considered as 25 and 20 stages, respectively. For brackish water at a temperature difference of 0.96 K (1.73oF), the energy requirement is 2.0 kWh/m3 (7.53 kWh/kgal). At this condition, the estimated water cost is $0.39/m3 ($1.48/kgal) achieved with 10,000,000 gal/day distillate, 30-year bond, 5% interest rate, and $0.05/kWh electricity. For seawater at a temperature difference of 0.44 K (0.80oF), the energy requirement is 3.97 kWh/m3 (15.0 kWh/kgal) and the estimated water cost is $0.61/m3 ($2.31/kgal). Greater efficiency of the vapor compression system is achieved by connecting multiple evaporators in series, rather than the traditional parallel arrangement. The efficiency results from the gradual increase of salinity in each stage of the series arrangement in comparison to parallel. Calculations using various temperature differences between boiling brine and condensing steam show the series arrangement has the greatest improvement at lower temperature differences. The following table shows the improvement of a series flow arrangement compared to parallel: ?T (K) Improvement (%)*1.111 2.222 3.333 15.21 10.80 8.37 * Incoming salt concentration: 3.5% Outgoing salt concentration: 7% Temperature: 450 K (350oF) Pressure: 928 kPa (120 psig) Stages: 4

Lubis, Mirna R.

2009-05-01T23:59:59.000Z

439

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

E-Print Network (OSTI)

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

Candalino, Robert Wilcox

2006-08-01T23:59:59.000Z

440

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

Science Conference Proceedings (OSTI)

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

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

1993-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydride vapor phase" 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.