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Fast-neutron total and scattering cross sections of elemental palladium

Description: Neutron total cross sections of palladium are measured from approx. = 0.6 to 4.5 MeV with resolutions of approx. = 30 to 70 keV at intervals of less than or equal to 50 keV. Differential neutron elastic- and inelastic-scattering cross sections are measured from 1.4 to 3.85 MeV at intervals of 50 to 100 keV and at 10 to 20 scattering angles distributed between approx. = 20 and 160/sup 0/. The experimental results are compared with respective quantities given in ENDF/B-V and used to deduce an opt… more
Date: June 1, 1982
Creator: Smith, A. B.; Guenther, P. T. & Whalen, J. F.
Partner: UNT Libraries Government Documents Department
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(The relationship between microstructure and magnetic properties in high-energy permanent magnets characterized by polytwinned structures)

Description: This report summarizes the results of a study of the relationship between microstructure and magnetic properties in a unique genre of ferromagnetic material characterized by a polysynthetically twinned structure which arises during solid state transformation. These results stem from the work over a period of approximately 27 months of a nominal 3 year grant period. The report also contains a proposal to extend the research project for an additional 3 years. The polytwinned structures produce an… more
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department
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Low cost hydrogen/novel membranes technology for hydrogen separation from synthesis gas, Phase 1. [Palladium-silver/poly(etherimide), polysulfone/poly(dimethylsiloxane)/poly(ether-esteramide)composite membranes]

Description: During this quarter, work continued on the development of high-flux palladium-silver membranes for the separation of hydrogen from carbon dioxide. Palladium-silver/poly(etherimide) composite membranes were prepared by a vacuum sputtering technique. The influence of different poly(etherimide) support membranes on the performance of palladium-silver membranes was investigated. All membranes tested showed a hydrogen/carbon dioxide selectivity lower than that of the uncoated poly(etherimide)/poly(d… more
Date: January 1, 1987
Partner: UNT Libraries Government Documents Department
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Catalyst and process development for hydrogen preparation from future fuel cell feedstocks. Quarterly progress report, January 1, 1980-March 31, 1980. [Pt/Rh, Pd, Pt, Rh, Ni/Rh, Rh/Re, Ni]

Description: Catalysts are being screened to steam reform hydrocarbons in an autothermal reformer (STR). Twenty-one samples have been screened in a 1-in.-diam (ATR) reactor using No. 2 oil as the hydrocarbon feed. A series of platinum-rhodium catalysts were evaluated to study the effect of varying compositions. A sample containing 1.7% Pt/0.3% Rh was most active but the difference among the samples was within the range of test variability. Development of a more realistic test has been started. The effect of… more
Date: April 1, 1980
Creator: Yarrington, R M; Feins, I R & Hwang, H S
Partner: UNT Libraries Government Documents Department
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Catalyst and process development for the H/sub 2/ preparation from future fuel cell feedstocks. Quarterly progress report, October 1, 1978-December 31, 1978

Description: The work done under this contract in the last quarter of 1978 was concerned with Phase I, which involved preliminary catalyst and process evaluation. The processes under study are hydrogen assisted steam reforming (HASR), catalytic partial oxidation (CPO), and autothermal steam reforming (ATR). Existing Engelhard test units were modified to carry out preliminary runs using the first two processes. Technical analysis to support work in this area consisted of heat and material balances constraine… more
Date: January 1, 1979
Creator: Yarrington, R M; Feins, I R; Hwang, H S & Mayer, C P
Partner: UNT Libraries Government Documents Department
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Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, October 1, 1979-September 30, 1980. [Ethane Elimination]

Description: The 1,1-reductive elimination of ethane from three cis-bis(phosphine)-dimethylpalladium complexes, L/sub 2/Pd(CH/sub 3/)/sub 2/ (L = PPh/sub 3/, PPh/sub 2/,CH/sub 3/ and L/sub 2/ = Ph/sub 2/PCH/sub 2/CH/sub 2/PPh/sub 2/), and three trans analogs (L = PPh/sub 3/, PPh/sub 2/CH/sub 3/ and L/sub 2/ = 2,11-bis(diphenylphosphinomethyl)benzo(c)phenanthrene (TRANSPHOS)) was carried out. The three cis complexes underwent reductive elimination in the presence of coordinating solvents (DMSO, DMF, and THF)… more
Date: September 1, 1980
Creator: Stille, J. K.
Partner: UNT Libraries Government Documents Department
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Development of low cost contacts to silicon solar cells. Final report, 15 October 1978-30 April 1980

Description: A summary of work done on the development of a copper based contact system for silicon solar cells is presented. The work has proceeded in three phases: (1) Development of a copper based contact system using plated Pd-Cr-Cu. Good cells were made but cells degraded under low temperature (300/sup 0/C) heat treatments. (2) The degradation in Phase I was identified as copper migration into the cells junction region. A paper study was conducted to find a proper barrier to the copper migration proble… more
Date: January 1, 1980
Creator: Tanner, D. P. & Iles, P. A.
Partner: UNT Libraries Government Documents Department
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Kinetic and infrared study of the effect of metal crystallite size and metal-support interactions on CO hydrogenation reactions: a third-year progress report

Description: Platinum and palladium supported on four different oxide materials - SiO/sub 2/, Al/sub 2/O/sub 3/, SiO/sub 2/-Al/sub 2/O/sub 3/, and TiO/sub 2/ - have been studied in depth. Different preparative techniques were utilized to vary metal particle size and change the state of the metal. For example, Pt and Pd deposited on TiO/sub 2/ and reduced at low temperatures (175 to 200/sup 0/C) exhibit normal adsorption behavior, whereas these same catalysts reduced at a high temperature (500/sup 0/C) trans… more
Date: January 1, 1980
Creator: Vannice, M. A.
Partner: UNT Libraries Government Documents Department
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Unit Operations Section Monthly Progress Report, November 1961

Description: Openation of a 6-in.-dia foam separation column with Sr/sup 89/ tracer and dodecylbenzenesulfonate as a surfactant and foaming agent was continued. The catalytic oxidation of H/sub 2/, CO, and CH/sub 4/ was studied using a nickel- chromepalladium ribbon catalyst. A Mark I prototype fuel assembly was sheared to within 1.5-in. of the end by modifying the gas hydraulic system of the shear. The force required to shear a highly carburized Mark I fuel assembly ductile tubing. Demonstration of the mec… more
Date: May 16, 1962
Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.
Partner: UNT Libraries Government Documents Department
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Systematics of gamma decay through low-lying vibrational levels of even--even nuclei excited by (p,p') and (n,n') reactions

Description: A series of experiments was performed in which gamma-ray spectra were measured, using a Ge(Li) detector, for incident 7 to 26-MeV protons on the even-even vibrational nuclei /sup 56/Fe, /sup 62/Ni, /sup 64/Zn, /sup 108/Pd, /sup 110/Cd, /sup 114/Cd, /sup 116/Cd, /sup 116/Sn, /sup 120/Sn, and /sup 206/Pb, and for incident 14-MeV neutrons on natural Fe, Ni, Zn, Cd, Sn, and Pb. These measurements yielded gamma-ray cross sections from which it was inferred that almost all of the gamma cascades from … more
Date: June 30, 1977
Creator: Koopman, R. P.
Partner: UNT Libraries Government Documents Department
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Recovery of cesium, technetium, rhodium and palladium from stored waste supernates

Description: The results of our assessment of the processing methods and costs for the recovery of cesium, techneium, rhodium, and palladium from aged waste supernates are presented. Guidelines for the assessment of costs are given. Cesium can be readily absorbed from alkaline waste supernates without prior treatment using Linde AW-500, a synthetic zolite. Technetium, present in the supernate as the pertechnetate anion, together with rhodium and palladium, probably present as anionic nitrite complexes, can … more
Date: June 22, 1966
Partner: UNT Libraries Government Documents Department
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Dislocation-hydrogen correlation in metals

Description: We present a method using SANS experiments to measure correlation between dislocations and absorbed hydrogen in metals. The technique involves sequential measurements first on a metal with dislocation networks, then two further measurements on the same sample infused with deuterium and normal hydrogen. SANS experiments on metals with dislocations networks have been performed a number of times and some results have appeared in the literature. We have computer estimates of the contribution of abs… more
Date: November 1, 1987
Creator: Summerfield, G.C.; King, J.S.; Heuser, B.; Epperson, J.E. (Michigan Univ., Ann Arbor, MI (USA). Dept. of Nuclear Engineering & Argonne National Lab., IL (USA))
Partner: UNT Libraries Government Documents Department
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HOMOGENEOUS REACTOR PROGRAM PROGRESS REPORT FOR PERIOD FROM DECEMBER 1, 1960 TO MAY 31, 1961

Description: Homogoenous Reactor Test. Four HRT runs were performed to study the reactor behavior with downward core flow. The upper patch was found to have fallen out, resulting in an increase in core-to-blanket mixing. The reactor will not be operated again. In the HRT processing plant, the development of a process for removing Ni and other soluble contaminants from fuel solutions by peroxide precipitation was continued, and efficiency tests of stackfllter iodine traps were performed. Power-trace data and… more
Date: September 1, 1961
Partner: UNT Libraries Government Documents Department
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Studies of heavy-ion reactions and transuranic nuclei

Description: The development of the cold-fusion'' episode is reviewed. Ongoing studies of compound-nucleus formation and decay via the neutron multiplicity distribution confirm the validity of conventional statistical theory. The excitation energy partition in near-barrier damped {sup 58}Ni + {sup 208}Pb collisions is found to be largely independent of the direction of net mass transfer, supporting a diffusion-like nucleon-exchange mechanism. Exclusive experiments on the heavy reaction systems {sup 197}Au +… more
Date: August 1, 1991
Creator: Schroeder, W. U. & Huizenga, J. R.
Partner: UNT Libraries Government Documents Department
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Studies in Semiconducting Metal Oxides in Conjunction With Silicon for Solid State Gas Sensors. Progress Report for April 1, 1977--March 31, 1978

Description: ZnO films have been reproducibly grown using chemical deposition and radio-frequency sputtering techniques. These films are polycrystalline or amorphous, but are stable, uniform and lend themselves to material characterization by Auger and x-ray analysis techniques, and electrical measurements. SnO/sub 2/ films have been reproducibly grown by chemical vapor deposition, vacuum deposition and radio-frequency sputtering techniques. These films are also polycrystalline or amorphous, and lend themse… more
Date: April 1, 1978
Creator: Jordan, A. G.
Partner: UNT Libraries Government Documents Department
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Preliminary investigation of a technique to separate fission noble metals from fission product mixtures

Description: A variation of the gold-ore fire assay technique was examined as a method for recovering Pd, Rh and Ru from fission products. The mixture of fission product oxides is combined with glass-forming chemicals, a metal oxide such as PbO (scavenging agent), and a reducing agent such as charcoal. When this mixture is melted, a metal button is formed which extracts the noble metals. The remainder cools to form a glass for nuclear waste storage. Recovery depended only on reduction of the scavenger oxide… more
Date: August 1, 1982
Creator: Mellinger, G. B. & Jensen, G. A.
Partner: UNT Libraries Government Documents Department
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Development of Liquid-Phase Sintering Techniques for Molybdenum Alloys. Final Report

Description: An envelope-type microstructure produced by liquidphase sintering techniques was used to develop ductiIe molybdenum-base alloys for sodium-cooled fast reactor application. A total of 105 compositions was examined; 21 showed evidence of room-temperature ductility, and a number of other compositions appeared promising. The prerequisites for obtaining ductile liquid-phase sintered materials were demonstrated. The most ductile alloys produced are based on the Mo--Pd--Cu and Mo --W--Ni--Fe systems. … more
Date: November 10, 1960
Partner: UNT Libraries Government Documents Department
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Probe molecule studies: Active species in alcohol synthesis

Description: The goal of this research is to develop a better understanding of the mechanisms of formation of alcohols and other oxygenates from syngas over supported catalysts. Different probe molecules are planned to add in situ during the reaction to help delineate reaction path ways and identify reaction intermediate species. The key of our study is to investigate how the species generated by these probe molecules interact with surface species present during oxygenate formation. CO hydrogenation reactio… more
Date: July 1, 1991
Creator: Blackmond, D.G. & Wender, I.
Partner: UNT Libraries Government Documents Department
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