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Rigid muffin-tin approximation for the electron-phonon interaction in transition metals

Progress in calculating the electron-phonon parameters of transition metals has been based on either the rigid muffin-tin approximation (RMTA) or the fitted modified tight-binding approximation (FMTBA). The RMTA has been shown to be remarkably accurate for average electron-phonon properties, but there are indications that RMTA matrix elements may be too small at low momentum transfer. An attempt is made to demonstrate these assertions concerning the accuracy of RMTA and the numerous electron-ph… more

Date: January 1, 1980

Creator: Butler, W. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recovery of deformed and hydrogen-charge palladium

Positron lifetime and Doppler-broadening studies made at 300 K have been used to investigate the interaction between interstitial hydrogen and lattice defects in deformed Pd. Specimens were charged with hydrogen at 300 K to levels up to 0.1%. The presence of hydrogen was found to have no effect on the recovery curves of Pd upon annealing to 400/sup 0/C. By 400/sup 0/C the values for both lifetime and Doppler-broadening for both cold worked and cold worked plus hydrogen were below the values obt… more

Date: January 1, 1982

Creator: Snead, C. L. Jr.; Lynn, K. G. & Lynch, J. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Decommissioning of a grout- and waste-filled storage tank in the 200 East Area of the Hanford Site

A self-concentrating waste tank located at the Strontium Semiworks Facility in the 200 East Area of the Hanford Site will be decommissioned following waste removal. During a previous decommissioning phase, the tank, thought to be empty, was filled with grout to prevent it from collapsing over time. Several years later, an agitator rod was pulled from within the tank and found to contain significant amounts of radiation, indicating there was still radioactive waste in the tank. Several alternati… more

Date: January 1, 1991

Creator: Marske, S.G.

Item Type: Article

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, October 1, 1979-December 31, 1979. [Pt/Rh, Ni/Rh, Ni/Pt/Rh, Ni, Ni/Ru, Ni/Pt, Ni/Co]

Twelve steam reforming catalysts were evaluated using an autothermal reforming screening unit. Duplicate tests were run with two samples to determine test variability. The samples tested contained either base metals, precious metals, or combinations of base and precious metals. The test was capable of distinguishing among samples where gross variations in composition are the main factor; for example, catalysts containing 2% by weight precious metals are more active than catalysts containing 15%… more

Date: January 1, 1980

Creator: Yarrington, R M; Feins, I R; Hwang, H S & Mayer, C P

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Alkali sorber (RABSAM), September 1, 1990--August 30, 1991

The objective of this work is to develop a regenerable activated-bauxite sorber alkali monitor that requires no high-temperature/high-pressure sampling line for the reliable in situ measurement of alkali-vapor concentration in the exhaust from the pressurized fluidized-bed combustion of coal. 11 refs., 2 figs., 1 tab.

Date: January 1, 1991

Creator: Lee, S. H. D. & Swift, M. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Solar-thermal energy conversion and storage: cyclohexane dehydrogenation. Progress report, 30 September 1977-30 June 1978

The objective of this project is to provide research support for the benzene/cyclohexane heat pipe development program at Sandia. The kinetics of the cyclohexane decomposition (energy collection) reaction over a commercially available naphtha reforming catalyst (RD-150, Englehard Industries) in the temperature range 400 to 800/sup 0/F and pressures of 1 to 40 atmospheres were measured. Significant amounts of side products such as toluene and butane were identified at temperatures above 550/sup … more

Date: July 1, 1978

Creator: Ritter, A.B.; DeLancey, G.B.; Schneider, J. & Silla, H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Preliminary analyses of soils and vegetation in the vicinity of the Mohave Generating Station in southern Nevada

No Description Available.

Date: April 1, 1975

Creator: Turner, F. B.; Romney, E. M.; Logan, R. F.; Leavitt, V. D.; Ackerman, T. L.; Alexander, G. V. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Aerial radiometric and magnetic survey, San Angelo National Topographic Map: Texas, West Texas Project. Final report

The results of analyses of the airborne gamma radiation and total magnetic field survey flown for the region identified as the San Angelo National Topographic Map NH14-1 are presented. The airborne data gathered are reduced by ground computer facilities to yield profile plots of the basic uranium, thorium, and potassium equivalent gamma radiation intensities, ratios of these intensities, aircraft altitude above the earth's surface, total gamma ray and earth's magnetic field intensity, correlate… more

Date: May 1, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Di-leptons at the Bevalac

Recent results on the production of di-leptons measured by the Di-Lepton-Spectrometer (DLS) collaboration are discussed. Results are reported from observations made on p /plus/ Be collisions with proton beams from 1.0 to 4.9 GeV and on Ca collisions with calcium beams of 1.0 to 2.0 GeV/A. The shape of the distributions are similar to that at higher energies. The low mass cross section appears to be explained by ..pi..-..pi.. annihilation, but detailed calculations are needed to substantiate tha… more

Date: March 1, 1988

Creator: Matis, H.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Use of molybdenum ion source electrodes at RTNS-II

Reports are reported for an ongoing effort to optimize D+ beam production by the MATS-III ion source used at RTNS-II. The three seven-aperture electrodes, originally consisting of water-cooled copper, have now been tested using uncooled molybdenum and with water cooling on the second (decel) electrode only. Details of the change, the results of the testing, and the benefits in operation, performance and cost are given.

Date: September 29, 1986

Creator: Massoletti, D.J.; Harter, G.A. & Heikkinen, D.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Testing program for determining the mechanical properties of concrete to temperatures of 621/sup 0/C

Concrete temperatures in a Liquid Metal Fast Breeder Reactor (LMFBR) in excess of normal code limits can result from postulated large sodium spills in equipment cells. Elevated temperature concrete property data which may have application for providing a basis for the design and evaluation of such postulated accident conditions is limited. Data thus needed to be developed commensurate with LMFBR plant applications for critical physical and mechanical concrete properties under prototypic thermal… more

Date: January 1, 1980

Creator: Oland, C.B.; Naus, D.J. & Robinson, G.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Neutron environment in d + Li facilities

A microscopic d + Li neutron yield model has been developed based upon classical models and experimental data. Using equations suggested by the Serber and evaporation models, a generalized least squares adjustment procedure generated angular yields for E/sub d/ to 40 MeV using the available experimental data. The HEDL-UCD experiment at E/sub d/ = 35 was used to adjust parameters describing the neutron spectra. The model is used to predict yields, spectra, and damage responses in the FMIT Test C… more

Date: January 1, 1980

Creator: Mann, F. M.; Schmittroth, F. & Carter, L. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Organic components of nuclear wastes and their potential for altering radionuclide distribution when released to soil

Normal waste processing at the Hanford operations requires the use of many organic materials, chiefly in the form of complexing agents and diluents. These organic materials and their chemical and radiolytic degradation products, have potential for complexing fission products and transuranium elements, both in the waste streams and upon infiltration into soil, perhaps influencing future sorption or migration of the nuclides. Particular complexation characteristics of various nuclides which const… more

Date: August 1, 1980

Creator: McFadden, K.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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TCT hybrid preconceptual blanket design studies

The conceptual design of a tokamak fusion-fission (hybrid) reactor, which produces electric power and fissile material, has been performed in a cooperative effort between Princeton's Plasma Physics Laboratory (PPPL) and Battelle's Pacific Northwest Laboratories (PNL). PPPL, who had overall project lead responsibility, designed the fusion driver system. Its core consists of a tokamak plasma maintained in the two-component torus (TCT) mode by both D and T beams and having a single null poloidal d… more

Date: January 1, 1978

Creator: Aase, D. T.; Bampton, M. C. C.; Doherty, T. J.; Leonard, B. R.; McCann, R. A.; Newman, D. F. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Thorium fuel cycles for LWRs: fuel diversion assessments and recycle requirements

A number of fuel cycles have been proposed for evaluation in the nonproliferation alternative systems assessment program. Among these systems are light water reactors (LWR) operating on the thorium-uranium cycle or the plutonium-thorium cycle either inside or outside energy centers. These proposals support the President's nuclear power policy of accelerating research into alternative fuel cycles that do not permit direct access to materials usable for nuclear weapons but still retain the benefi… more

Date: January 1, 1978

Creator: Carter, W. L.; Rainey, R. H. & Johnson, D. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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First order study for an iron core OH system for TNS

A simple comparison has been made between an air core and an iron core ohmic heating system for a particular device, and it was shown that the peak power requirements can be substantially reduced by the use of an iron core to power levels handled by industry today. It was also shown that for an ohmic heating system initiated plasma that the cost of the iron core ohmic heating power system (iron core, dual rectifier, and DC switch) is less than the cost for a subset of the power system for an ai… more

Date: January 1, 1977

Creator: Ballou, J. K. & Schultz, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Cause of pitting in beryllium

Light microscopy, bare-film radiography, secondary ion mass spectroscopy, electron microprobe and physical testing were used to examine beryllium specimens exhibiting a stratified, pitted, pattern after chemical milling. The objective was to find the cause of this pattern. Specimens were found to have voids in excess of density specification allowances. These voids are attributed, at least in part, to the sublimation of beryllium fluoride during the vacuum hot pressing operation. The origin of … more

Date: April 16, 1982

Creator: Kershaw, R. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Cadmium sulfide/copper sulfide heterojunction cell research. Final report, February 26, 1979-July 15, 1980

Extensive modifications were made to the multi-source deposition apparatus. These include the installation of a larger vacuum chamber on the existing system. The new chamber provides improved inter-source shielding, an improved substrate mounting and heating system, and a vacuum interlock for introducing substrates. CdS resistivity control by both In doping and off-stoichiometric deposition has been investigated. Indium doping has been achieved both by diffusion from a pre-deposited In layer an… more

Date: June 30, 1980

Creator: Thornton, J. A. & Cornog, D. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A benchmark-problem specification and calculation using SENSIBL, a one- and two-dimensional sensitivity and uncertainty analysis code of the AARE system

The lack of suitable benchmark problems makes it difficult to test sensitivity codes with a covariance library. A benchmark problem has therefore been defined for one- and two-dimensional sensitivity and uncertainity analysis codes and code systems. The problem, representative of a fusion reactor blanket, has a simple, three-zone )tau)-z geometry containing a D-T fusion neutron source distributed in a central void region surrounded by a thick /sup 6/LiH annulus. The response of interest is the … more

Date: January 1, 1988

Creator: Muir, D. W.; Davidson, J. W.; Dudziak, D. J.; Davierwalla, D. M.; Higgs, C. E. & Stepanek, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recovery of plutonium and americium from chloride salt wastes by solvent extraction

Plutonium and americium can be recovered from aqueous waste solutions containing a mixture of HCl and chloride salt wastes by the coupling of two solvent extraction systems: tributyl phosphate (TBP) in tetrachloroethylene (TCE) and octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) in TCE. In the flowsheet developed, the salt wastes are dissolved in HCl, the Pu(III) is oxidized to the IV state with NaClO/sub 2/ and recovered in the TBP-TCE cycle, and the Am is then removed from t… more

Date: January 1, 1987

Creator: Reichley-Yinger, L. & Vandegrift, G.F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Geostatistics project of the National Uranium Resource Evaluation program

Additional work has been done to display radiometric data from the Lubbock quadrangle in pseudocolor maps. A digitized topographic map of the quadrangle was obtained from the U.S. Geological Survey and this is being incorporated into the study of the radiometric data. Single-record data from the Lake Mead calibration range and from the Slayton test line have been obtained from GeoMETRICS: Inc. and analysis of this data has begun. Principal component analyses have been used to investigate the re… more

Date: February 1, 1978

Creator: Bement, T.R.; McKay, M.D. & Wecksung, G.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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An Evaluation of liquid metal leak detection methods for the Clinch River Breeder Reactor Plant

This report documents an independent review and evaluation of sodium leak detection methods described in the Clinch River Breeder Reactor Preliminary Safety Analysis Report. Only information in publicly available documents was used in making the assessments.

Date: December 1, 1977

Creator: Morris, C. J. & Doctor, S. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effect of fuel recycling on radioactivity and thermal power of high-level wastes

The radioactivity and thermal power of high-level and plutonium-bearing wastes from the nuclear fuel cycle have been calculated for the years 1975 to 2005 using the rate of generation of such wastes projected for the Generic Environmental Statement on Mixed Oxide Fuel (NUREG-0002). Three modes of fuel recycle are considered: (1) no recycle, (2) uranium recycle, and (3) prompt uranium and plutonium recycle. These cases are compared with a respect to radioactivity and thermal power of the generat… more

Date: October 1, 1977

Creator: Wachter, J.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Plutonium scrap recovery at Savannah River: Past, present, and vision of the future

As a result of the changing requirement, plus environmental and regulatory commitments, SRP now has essentially completed its paradigm shift. SRP has been transformed from primarily a reprocessor of irradiated uranium targets to primarily a reprocessor of non-specification plutonium. This is the mission which will carry SRP into the 21st Century. Accomplishment of the defined goals for the three-pronged RandD program will achieve several objectives: exploit new processes for recovering low-grad… more

Date: January 1, 1988

Creator: Gray, Leonard W.; Gray, John H.; Blancett, Allen L.; Lower, William M. & Rudisill, Tracy S.

Item Type: Article

Partner: UNT Libraries Government Documents Department