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Radiolytic and Radiolytically Induced Generation of Gases from Synthetic Wastes : Final Report

Description: To better understand the processes leading to the generation and release of gases from waste tanks, the authors studied the radiolytic and thermal generation of H2, N2O, N2, O2, and NH3 in nonradioactive waste simulant solutions and slurries. The radiolytic sources for H2 are e(sub aq)⁻ and its predecessors and H atoms. Radiolysis of the water generates some H2 and an additional amount comes from the hydrogen abstraction reaction H + RH(yields) H2+R(center_dot). Nitrate scavenges e(sub aq)(sup … more
Date: October 1993
Creator: Meisel, Dan; Jonah, Charles D.; Kapoor, S.; Matheson, Max S. & Sauer, M. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Gas Generation from Hanford Grout Samples : Final Report

Description: The radiolytic yields of hydrogen nitrogen, oxygen, nitrous oxide, and carbon monoxide from two batches of WHC-supplied samples of grouted simulated waste have been (gamma) irradiated at several dose rates (0.025, 0.63 and 130 krad/h for hydrogen and 130 krad/h for all other gases). In one batch, the liquid waste simulant that was added to the grout included the original components that were added to Tank 102-AP (labeled "virgin" waste.) The second batch included a similar liquid waste simulant… more
Date: March 1994
Creator: Jonah, Charles D.; Kapoor, S.; Matheson, Max S.; Mulac, W. A. & Meisel, Dan
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tritium and Hydrogen Transport in LMFBR Systems: EBR-II, CRBR, and FFTF

Description: A tritium and hydrogen transport model has been employed to simulate concentration profiles, tritium losses to auxiliary containment systems, and cold trap burdens for EBR-II, CRBR, and FFTF. Experimental data from EBR-II were found to correlate well with calculated tritium and hydrogen profiles. A major change relative to previous transport models, namely, the inhibiting effect of oxide coatings on tritium permeation through reactor structural surfaces, has been incorporated into the current m… more
Date: September 1978
Creator: Renner, T. A. & McPheeters, C. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Fluorine and Hydrogen Radical Species on Modified Oxidized Ni(pt)si

Description: NiSi is an attractive material in the production of CMOS devices. The problem with the utilization of NiSi, is that there is no proper method of cleaning the oxide on the surface. Sputtering is the most common method used for the cleaning, but it has its own complications. Dry cleaning methods include the reactions with radicals and these processes are not well understood and are the focus of the project. Dissociated NF3 and NH3 were used as an alternative and XPS is the technique to analyze th… more
Date: May 2010
Creator: Gaddam, Sneha Sen
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Kinetic Studies of Hydroxyl and Hydrogen Atom Reactions

Description: Gas phase kinetics of the reactions involving hydroxyl radical and hydrogen atom were studied using experimental and ab initio theoretical techniques. The rate constant for the H + H2S reaction has been measured from 298 to 598 K by the laser photolysis/resonance fluorescence (LP-RF) technique. The transition state theory (TST) analysis coupled with the measurements support the suggestion that the reaction shows significant curvature in the Arrhenius plot. The LP-RF technique was also used to… more
Date: May 2002
Creator: Hu, Xiaohua
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Reaction of Hydrogen With Uranium

Description: Report discussing reaction of hydrogen with uranium in a range of temperatures and pressures. Experimental materials, methods and results are included.
Date: February 17, 1955
Creator: Albrecht, William M. & Mallett, Manley William, 1909-
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Reaction Between Hydrogen and Oxygen by Catalysis and the Thermal Reaction

Description: From abstract: "The reaction between hydrogen and oxygen with the aid of various catalysts (especially platinum on aluminua) has been studied, and the operating variables such as flow rates, space velocity, temperature, and gas composition have been examined rather extensively. It has been found that hydrogen and oxygen in stoichiometric proportions and mixed with either steam or helium may be made to react to the extent of 99.5% or greater at space velocities up to 30,000 hr-1, or even higher,… more
Date: January 15, 1952
Creator: Kuhn, D. W.; Ryon, A. D.; Palko, A. A. & Clewett, G. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Report on Shock Tube Experiments

Description: Abstract: An investigation of ionization by shock waves in hydrogen has been initiated. The shock waves are produced in a 1-inch diameter glass pipe by a high-voltage spark at one end. Variables which will influence attainment of the maximum degree of ionization and ion temperature are described. Spectroscopic methods of measuring ion density and temperature are outlined, and improvements in the design of the shock tube are discussed.
Date: March 24, 1955
Creator: Huber, Elsa L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of an inter-atomic potential for the Pd-H binary system.

Description: Ongoing research at Sandia National Laboratories has been in the area of developing models and simulation methods that can be used to uncover and illuminate the material defects created during He bubble growth in aging bulk metal tritides. Previous efforts have used molecular dynamics calculations to examine the physical mechanisms by which growing He bubbles in a Pd metal lattice create material defects. However, these efforts focused only on the growth of He bubbles in pure Pd and not on bubb… more
Date: September 1, 2007
Creator: Zimmerman, Jonathan A.; Hoyt, Jeffrey John (McMaster University, Hamilton, Ontario, Canada); Leonard, Francois Leonard; Griffin, Joshua D. & Zhou, Xiao Wang
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Wall pressure exerted by hydrogenation of sodium aluminum hydride.

Description: 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 influ… more
Date: June 1, 2009
Creator: Perras, Yon E.; Dedrick, Daniel E. & Zimmerman, Mark D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fuel traps: mapping stability via water association.

Description: Hydrogen storage is a key enabling technology required for attaining a hydrogen-based economy. Fundamental research can reveal the underlying principles controlling hydrogen uptake and release by storage materials, and also aid in characterizing and designing novel storage materials. New ideas for hydrogen storage materials come from exploiting the properties of hydrophobic hydration, which refers to water s ability to stabilize, by its mode of association, specific structures under specific co… more
Date: March 1, 2007
Creator: Rempe, Susan L.; Clawson, Jacalyn S.; Greathouse, Jeffery A.; Alam, Todd M; Leung, Kevin; Varma, Sameer et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Equations of state for hydrogen and deuterium.

Description: This report describes the complete revision of a deuterium equation of state (EOS) model published in 1972. It uses the same general approach as the 1972 EOS, i.e., the so-called 'chemical model,' but incorporates a number of theoretical advances that have taken place during the past thirty years. Three phases are included: a molecular solid, an atomic solid, and a fluid phase consisting of both molecular and atomic species. Ionization and the insulator-metal transition are also included. The m… more
Date: December 1, 2003
Creator: Kerley, Gerald Irwin (Kerley Technical Services, Appomattox, VA)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Interim report:feasibility of microscale glucose reforming for renewable hydrogen.

Description: Micro-scale aqueous steam reforming of glucose is suggested as a novel method of H{sub 2} production for micro fuel cells. Compact fuel cell systems are a viable alternative to batteries as a portable electrical power source. Compared with conventional lithium polymer batteries, hydrocarbon powered fuel cells are smaller, weigh less, and have a much higher energy density. The goal of this project is to develop a hydrocarbon powered microfuel processor capable of driving an existing microfuel ce… more
Date: March 1, 2007
Creator: Norman, Kirsten (New Mexico Institute of Mining and Technology, Socorro, NM)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A microBio reactor for hydrogen production.

Description: The purpose of this work was to explore the potential of developing a microfluidic reactor capable of enzymatically converting glucose and other carbohydrates to hydrogen. This aggressive project was motivated by work in enzymatic hydrogen production done by Woodward et al. at OWL. The work reported here demonstrated that hydrogen could be produced from the enzymatic oxidation of glucose. Attempts at immobilizing the enzymes resulted in reduced hydrogen production rates, probably due to buffer … more
Date: December 1, 2003
Creator: Volponi, Joanne V. & Walker, Andrew William
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Processing of NiTi Shape Memory Alloys through Low Pressure and Low Temperature Hydrogen Charging

Description: Many industries including the medical, aerospace, and automobile industries have increasingly adopted the use of shape memory alloys (SMAs) for a plethora of applications due to their unique thermomechanical properties. From the commercially available SMAs in the market, binary NiTi SMAs have shown the most desirable properties. However, SMA properties can be significantly affected by the fabrication process. One of the most familiar applications of NiTi SMAs is in the design of actuating devic… more
Date: May 2018
Creator: Briseno Murguia, Silvia
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Trapping of hydrogen in Hf-based high κ dielectric thin films for advanced CMOS applications.

Description: In recent years, advanced high κ gate dielectrics are under serious consideration to replace SiO2 and SiON in semiconductor industry. Hafnium-based dielectrics such as hafnium oxides, oxynitrides and Hf-based silicates/nitrided silicates are emerging as some of the most promising alternatives to SiO2/SiON gate dielectrics in complementary metal oxide semiconductor (CMOS) devices. Extensive efforts have been taken to understand the effects of hydrogen impurities in semiconductors and its behavi… more
Date: December 2007
Creator: Ukirde, Vaishali
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Radiation Chemistry of Synthetic Waste

Description: The yield of hydrogen from radiolysis of aqueous solutions is substantially reduced by the presence of nitrate and nitrite in the waste solutions. Nitrate is more efficient in scavenging the precursors to hydrogen than is nitrite, therefore, the latter should be maintained at higher levels if minimization of radiolytic gas production is required. Nitrate is the major scavenger for e(sub aq)(sup (minus)) and nitrite is the major scavenger for H atoms. At the concentration levels of the waste sol… more
Date: November 1991
Creator: Meisel, Dan; Diamond, H.; Horwitz, E. P.; Jonah, Charles D.; Matheson, Max S.; Sauer, M. C. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Evaluation of hydrogen trapping in HfO2 high-κ dielectric thin films.

Description: Hafnium based high-κ dielectrics are considered potential candidates to replace SiO2 or SiON as the gate dielectric in complementary metal oxide semiconductor (CMOS) devices. Hydrogen is one of the most significant elements in semiconductor technology because of its pervasiveness in various deposition and optimization processes of electronic structures. Therefore, it is important to understand the properties and behavior of hydrogen in semiconductors with the final aim of controlling and using … more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: August 2006
Creator: Ukirde, Vaishali
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Special Developments Project Progress Report 2: February 1, 1954 to November 1, 1954

Description: Abstract: Further work has been done towards developing a high-output hydrogen ion source using the principle of the Ti ion source, the release of ions from hydrogenated titanium. It is concluded that previous efforts had resulted in the production of large quantities of low-energy ions but had failed in the attempt to accelerate a significant fraction of these. A new approach is undertaken that involves an entirely different geometry. Successfully accelerated and focused beams are obtained. Pe… more
Date: November 1954
Creator: Ruby, Lawrence
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Screening analysis of solar thermochemical hydrogen concepts.

Description: A screening analysis was performed to identify concentrating solar power (CSP) concepts that produce hydrogen with the highest efficiency. Several CSP concepts were identified that have the potential to be much more efficient than today's low-temperature electrolysis technology. They combine a central receiver or dish with either a thermochemical cycle or high-temperature electrolyzer that operate at temperatures >600 C. The solar-to-hydrogen efficiencies of the best central receiver concept… more
Date: March 1, 2008
Creator: Diver, Richard B., Jr. & Kolb, Gregory J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Performance testing of aged hydrogen getters against criteria for interim safe storage of plutonium bearing materials.

Description: Hydrogen getters were tested for use in storage of plutonium-bearing materials in accordance with DOE's Criteria for Interim Safe Storage of Plutonium Bearing Materials. The hydrogen getter HITOP was aged for 3 months at 70 C and tested under both recombination and hydrogenation conditions at 20 and 70 C; partially saturated and irradiated aged getter samples were also tested. The recombination reaction was found to be very fast and well above the required rate of 45 std. cc H2h. The gettering … more
Date: January 1, 2006
Creator: Shepodd, Timothy J.; Nissen, April & Buffleben, George M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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