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Preparation of Charge Materials for Ornl Electromagnetic Isotope Separators

Description: SEPARATORS. C. W. Sheridan, H. R. Gwinn, and L. O. Descriptions are given of procedures, techniques, and equipment used to prepare charge materials for electromagnetic isotope separators at ORNL. Data on ion outputs during processing, charge consumption rates, and process efficiencies are given for 54 elements. (auth)
Date: August 1, 1962
Creator: Sheridan, C W; Gwinn, H R & Love, L O
Partner: UNT Libraries Government Documents Department
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WELDING AND BRAZING OF HIGH-TEMPERATURE RADIATORS AND HEAT EXCHANGERS

Description: Procedures were developed for fabricating highperformance radiators and heat exchangers for the Aircraft Nuclear Propulsion (ANP) Program. These components, which contain multitudes of tube-to-tube sheet and tube-to-fin joints, are similar in design to those under consideration for a variety of space vehicle applications. In order to ensure reliability of the tube-to-tube sheet joints, techniques producing welds of extremely high quality were used and back brazing of the welds with a suitable alloy was incorporated. High-temperature brazing was also incorporated to attach high-conductivity fins to Inconel tubes in the radiators. The selection of a suitable brazing alloy for these applications was dependent upon several factors, including corrosion and oxidation resistance, flow point, and mechanical properties. A Ni- Si-B alloy was found to be adequate from all these considerations. Special brazing procedures were developed to obtain satisfactory flowability of this brazing alloy on tube-to-fin joints. The suitability of these fabrication procedures for the very stringent service conditions to which the radiators and heat exchangers were subjected was demonstrated by testing full-size components under operating conditions. (auth)
Date: February 20, 1962
Creator: Slaughter, G.M. & Patriarca, P.
Partner: UNT Libraries Government Documents Department
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Microcrystalline silicon growth for heterojunction solar cells. Second quarterly report, 1 April 1983-30 June 1983

Description: In this reporting period, a single source of evaporation with B mixed with highly doped Si was used instead of the co-evaporation of separate Si and B sources. The purpose was to reduce possible carbon contamination. The results of both the heterojunction or heteroface structures, however, were similar to last quarter when evaporation was used. The best Voc of the heterojunction was about 460mV and no improvement in Voc in the heteroface structure, was observed; slight Voc degradation occurred. A study of the p m-Si/p c-Si structure showed a negative Voc in many cases. The highest /sup 0/C voltage was up to -150mV. This indicated that the interface properties between the two materials are such that instead of repelling minority carriers from the substrate carrier, collection actually occurred. This structure defeated the purpose, but it might also mean that n-type m-Si could be beneficial and should be included in future study. Another study of cells made in the part of substrates not covered by m-Si resulted in performance lower than the controls. This indicated possible substrate degradation in the process, the extent of which will be studied in the future.
Date: January 1, 1983
Creator: Iles, P. A.; Leung, D. C. & Fang, P. H.
Partner: UNT Libraries Government Documents Department
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Physical simulations of cavity closure in a creeping material

Description: The finite element method has been used extensively to predict the creep closure of underground petroleum storage cavities in rock salt. Even though the numerical modeling requires many simplifying assumptions, the predictions have generally correlated with field data from instrumented wellheads, however, the field data are rather limited. To gain an insight into the behavior of three-dimensional arrays of cavities and to obtain a larger data base for the verification of analytical simulations of creep closure, a series of six centrifuge simulation experiments were performed using a cylindrical block of modeling clay, a creeping material. Three of the simulations were conducted with single, centerline cavities, and three were conducted with a symmetric array of three cavities surrounding a central cavity. The models were subjected to body force loading using a centrifuge. For the single cavity experiments, the models were tested at accelerations of 100, 125 and 150 g's for 2 hours. For the multi-cavity experiments, the simulations were conducted at 100 g's for 3.25 hours. The results are analyzed using dimensional analyses. The analyses illustrate that the centrifuge simulations yield self-consistent simulations of the creep closure of fluid-filled cavities and that the interaction of three-dimensional cavity layouts can be investigated using this technique.
Date: September 1, 1985
Creator: Sutherland, H.J. & Preece, D.S.
Partner: UNT Libraries Government Documents Department
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Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

Description: The objective of this project is to provide the fundamental information on the mechanisms of bacterial leaching of pyrite. The knowledge of how bacterial leaching of pyrite functions is essential for design and development of a technology for coal cleaning with bacteria. The features of major electrochemical techniques will be examined to find out if any of them can provide a diagnostic information on the mechanisms of related reactions.
Date: January 1, 1992
Creator: Pesic, B.
Partner: UNT Libraries Government Documents Department
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Defects in metal crystals. Progress report, May 1, 1973--April 30, 1974

Description: Progress was made in the following areas: FIM (field ion microscopy) studies of defects in W irradiated with W ions or electrons; FIM studies of Au irradiated with Au or Xe ions; FIM and electrical resistivity study of vacancy defects in quenched W; FIM studies of dilute Pt alloys; measurement of the range of focused replacement sequences in Au; investigation of grain boundary strtucture (using Au); FIM observation of dissociated screw dislocations in Mo; calculation of properties of point defects in metals; and atom probe FIM. (auth)
Date: January 1, 1974
Creator: Balluffi, R.W. & Seidman, D.N.
Partner: UNT Libraries Government Documents Department
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Strontium-90 Fueled Thermoelectric Generator Power Source for Five-Watt U.S. Coast Guard Light Buoy. Final Report

Description: The objectives of the SNAP 7A program were to design, manufacture, test, and deliver a five-watt electric generation system for a U. S. Coast Guard 8 x 26E light buoy. The 10-watt Sr/sup 90/ thermoelectric generator, the d-c-to-d-c converter, batteries and the method of installation in the light buoy are describcd. The SNAP 7A generator was fueled with four capsules containing a total of 40,800 curies of Sr/sup 90/ titanate. After fueling and testing, the SNAP 7A electric generating system was installed in the Coast Guard light buoy at Baltimore, Maryland, on December 15, 1961. Operation of the buoy lamp is continuous. (auth)
Date: February 1, 1962
Partner: UNT Libraries Government Documents Department
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Pacific Northwest Laboratory, annual report for 1983 to the DOE Office of Energy Research. Part 4. Physical sciences

Description: Part 4 of the Pacific Northwest Laboratory Annual Report for 1983 to the Office of Energy Research, includes those programs funded under the title Physical and Technological Research. The Field Task Program Studies reports in this document are grouped under the subheadings and each section is introduced by a divider page that indicates the Field Task Agreement reported in that section. These reports only briefly indicate progress made during 1983. The reader should contact the principal investigators named or examine the publications cited for more details.
Date: February 1, 1984
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]

Description: 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% by weight nickel. The results show a decrease in hydrocarbon breakthrough as the weight of nickel charged to the constant volume reactor increases. A commercial nickel catalyst, G90C, appears slightly better than some Engelhard prepared samples of equal nickel concentrations due to the higher density of G90C. Visual observation of the used catalysts show that samples containing only precious metals (Pt/Rh) did not coke during the run. The samples containing only base metals (nickel, cobalt) were coked and were magnetic. Samples containing 14.5% nickel by weight with 0.5% precious metals by weight added were not coked, were not magnetic, and had a blue colored core as compared to the black core of the virgin samples. Some speculation about deactivation mechanisms based on these observations are made.
Date: January 1, 1980
Creator: Yarrington, R M; Feins, I R; Hwang, H S & Mayer, C P
Partner: UNT Libraries Government Documents Department
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Development of a High Velocity Solid Particle Launcher for Laboratory Erosion Studies. [Reentry Vehicle Heat Shields]

Description: A solid particle launcher for laboratory erosion studies has been developed and successfully demonstrated. Performance of the launcher is predicted by a two-dimensional, time-dependent theoretical analysis to within the experimental uncertainty. The present device accelerates 100 μm diameter glass spheres to velocities of 2.1+/- 0.6 km/sec. The system is safe, reliable, and has a test repetition of about 2 shots/hour.
Date: March 1, 1975
Creator: Aeschliman, D. P.; Mulac, A. J.; Guzman, J. A.; Eaton, R. R. & Fox, R. L.
Partner: UNT Libraries Government Documents Department
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GAS-COOLED REACTOR PROGRAM QUARTERLY PROGRESS REPORT FOR PERIOD ENDING SEPTEMBER 30, 1961

Description: Progress is reported on investigations in support of the Experimental Gas-Cooled Reactor, the Pebble-Bed Reactor Experiment, Advanced reactor design and development, test facilities, components, and materials. Topics covered include EGCR physics, EGCR performance analyses, structural investigations, EGCR component and materials development and testing, EGCR experimental facilities, PBRE physics and design studies, fueled-graphite investigations, clad fuel development, design studies of advanced power plants, experimental investigations of heat transfer and fluid flow, development of equipment anmd test facilities. and fabrication studies. (M.C.G.)
Date: February 1, 1962
Partner: UNT Libraries Government Documents Department
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AEC FUELS AND MATERIALS DEVELOPMENT PROGRAM. Seventh Annual Report.

Description: This report is the seventh annual report of the unclassified portion of the Fuels and Materials Development Programs being conducted by the General Electric Company's Nuclear Materials and Propulsion Operation under Contract AT(40-1)-2847, issued by the Fuels and Materials Branch, Division of Reactor Development and Technology, of the Atomic Energy Commission. This report covers the period from January 31, 1967 to January 31, 1968, and thus also serves as the quarterly progress report for the final quarter of the year.
Date: January 1, 1968
Partner: UNT Libraries Government Documents Department
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Examination of Uranium-2 w/o Zirconium Experimental Fuel Slugs Irradiated in EBR-I. Final Report-Program 6.1.11

Description: Six groups of U-2 wt% Zr fuel slugs were irradiated in the first core of the EBR-I to burnups of 0.080 to 0.189 at.% at calculated temperatures of 307 to 353 deg C. Two groups of cast specimens were found to be more dimensionally stable than four groups of wrought slugs. Of the wrought slungs, the as quenched group showed less tendency to grow than the three groups which had some annealing after quenching. Specimens at burnups of about 0.189 at.% and at 383 deg C showed the onset of swelling as indicated by density measurements. The hardnesses of these specimens seemed but little affected by radiation, but there was an indication of softening with increasing irradiation temperature. (auth)
Date: February 1, 1962
Creator: Murphy, W. F.; Klank, A. C. & Paine, S. H.
Partner: UNT Libraries Government Documents Department
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Photoinduced Charge Separation by Polymer-Bound Chromophores

Description: This project has examined the photodynamic behavior of water-soluble polymers that have covalently linked hydrophobic chromophores spaced along the chains. These polymeric systems have been examined for photoinduced charge separation with electron-accepting ions having different total charge. Focus has been on the excited singlet (S{sub 1}) state formed by laser flash absorption. The effects of pH and ionic strength -- factors that govern the conformational nature of the polymer in solution -- have been studied. A second major effort has been to study photoinduced redox processes involving excited states of water-soluble variants of anthracene and acridine. 27 refs., 16 figs., 2 tabs.
Date: September 1, 1991
Creator: Rodgers, M. A. J.
Partner: UNT Libraries Government Documents Department
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Structural analysis of the West Hackbery No. 6 SPR storage cavern

Description: Four separate structural analyses of the West Hackberry No. 6 SPR storage cavern are presented. One analysis covers the creep response of the cavern beginning shortly before the time when an accidental fire occurred and proceeding through the cavern recertification pressure test. The second analysis models the surface uplife that is expected during the same pressure test. The third and fourth numerical studies investigate the structural response of West Hackberry No. 6 to slabbing and a rapid pressure drop. All analyses indicate that this cavern should be structurally stable for the conditions assumed.
Date: August 1, 1980
Creator: Benzley, S.E.
Partner: UNT Libraries Government Documents Department
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