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Array automated assembly: Phase 2. Quarterly report

Description: An analysis was made of cost trade-offs for shaping modified square wafers from cylindrical crystals. For reasonably expectable silicon and sheet costs, the optimum shape will be nearer a circle than a square. Tests were conducted of the effectiveness of texture etching for removal of surface damage on sawed wafers. Four glass systems have survived preliminary screening tests for use as edge masking dielectrics. These include beta-spodumen, MgO-Al/sub 2/O/sub 3/ borosilicate, baria and titania … more
Date: February 1, 1978
Creator: Taylor, W.E.
Partner: UNT Libraries Government Documents Department
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Chemical Processing Technology Quarterly Progress Report, October-December 1961

Description: The ICPP processed Al fuel, prtncipally of the MTR-ETR type, durtng this quarter. Newly designed and installed processing equipment exhibited excellent operating performance. This included direct-air-pulsed extraction, stripping and scrub columns, and a cascade-controlled continuous evaporator in first cycle product concentration service. Aqueous zirconium fuel processing studies continued with the objective of adapting the hydrofluoric acid process to continuous dissolution-complexing to incre… more
Date: March 28, 1962
Creator: Bower, J. R.
Partner: UNT Libraries Government Documents Department
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Study of selected off-gases produced during the immobilization of nuclear wastes in the SYNROC process. Final report for year ended December 31, 1981. [Pollucite, CsAlSi/sub 2/O/sub 6/, and barium-cesium hollandite, (Ba,Cs)Al/sub 2/Ti/sub 6/O/sub 16/]

Description: Calculation of possible off-gases expected during the fabrication of SYNROC showed that volatilization of cesium would be a significant problem. Samples of the cesium containing minerals pollucite, CsAlSi/sub 2/O/sub 6/, and barium-cesium hollandite, (Ba,Cs)Al/sub 2/Ti/sub 6/O/sub 16/, were prepared for vaporization studies. Fifteen vaporization runs were made with the hollandite samples. With dry air as the carrier gas, the vapor pressure of cesium over Ba/sub 0/ /sub 8/Cs/sub 0/ /sub 4/Al/sub… more
Date: December 31, 1981
Creator: Carpenter, J.H.
Partner: UNT Libraries Government Documents Department
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Mechanisms of the oxidation of metals and alloys with emphasis on superconductors

Description: Research work performed at M.I.T. under this contract has had two major thrusts. One thrust deals with the oxidation processing of, and phase transformations in, the Yb{sub n}Ba{sub 2n}Cu{sub 3n+n}O{sub x} (n = 1, 2, {infinity}) superconducting oxide system while the second thrust deals with the optimization of the properties of oxidation processed Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub y}/Ag superconducting microcomposites.
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department
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Sequential purification and crystal growth for the production of low cost silicon substrates. Quarterly technical progress report No. 2, 1 January 1980-31 March 1980

Description: The objective of this program is to identify and develop low cost processing for fabricating large grain size polycrystalline silicon substrates. Metallurgical grade silicon (MG-Si) which is low cost and abundant for industrial usage was chosen as starting material. However, MG-Si cannot be used directly as substrates for solar cell fabrication; the further purification and recrystallization of MG-Si are needed. The conventional method of purifying MG-Si requires the conversion of Si to gaseous… more
Date: May 1, 1980
Creator: Liaw, M. & D'Aragona, F.S.
Partner: UNT Libraries Government Documents Department
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Superconducting materials

Description: Our research on high temperatures superconductors has produced novel insights for the normal state properties of copper oxides that have been discovered in the last few years. Advances in materials preparation have produced singly crystal samples, and sophisticated surface cleavage techniques have unveiled truly metallic behavior in many respects. Thus, the recent confirmation of a Fermi surface in several cuprate superconductors by photoemission spectroscopy has aroused interest in experimenta… more
Date: January 1, 1992
Creator: Ruvalds, J.
Partner: UNT Libraries Government Documents Department
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(Thermochemistry of phases related to oxide superconductors)

Description: The aim of this project has been to understand the crystal-chemical and energetic constraints on the stability of phases related to oxide superconductors, using high temperature reaction calorimetry, the unique expertise of this laboratory, coupled with synthesis and structural studies. The YBCO (Y{sub 2}O{sub 3}-BaO-Cu-O) system has been studied in detail by Zhou for his Ph.D. thesis, while DiCarlo has been studying alkaline earth doped lanthanium cuprates of the series La{sub 2-x}A{sub x}CuO{… more
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department
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Systematic Evaluation of Jc Decrease in Thick Film Coated Conductors

Description: Address both thickness dependence of Jc, in thick film YBCO coated conductors through an application of a suite of new measurement techniques to thick film wire samples produced by commercially viable coated conductor technologies.
Date: May 10, 2006
Creator: Ignatiev, Alex & Goyal, Dr. Amit
Partner: UNT Libraries Government Documents Department
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Physical-chemical studies of transuranium elements

Description: Major advances in our continuing program to determine, interpret, and correlate the basic chemical and physical properties of the transuranium elements are summarized. Research topics include: Molar enthalpies of formation of BaCmO{sub 3} and BaCfO{sub 3}; luminescence of europium oxychloride at various pressures; and anti-stokes luminescence of selected actinide (III) compounds. 42 refs., 4 figs., 2 tabs.
Date: January 1, 1991
Creator: Peterson, J.R.
Partner: UNT Libraries Government Documents Department
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Application of MeV ions to the analysis and modification of high temperature superconducting materials

Description: In analyzing the composition of high {Tc} superconducting materials using heavy-ion RBS we discovered that the electronic excitation of the target caused mixing to occur. To study this effect we made superlattice structures of alternating thin layers of Ba{sub 2}YCu{sub 3}O{sub 6+x} and BaF{sub 2}. At this point in the process some mixing has occurred, but the individual layers are still visible. However, as the bombardment continued the layers were mixed together. It may well be that one can u… more
Date: November 2, 1990
Creator: Tombrello, T.A.
Partner: UNT Libraries Government Documents Department
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Infrared detection with high-[Tc] bolometers and response of Nb tunnel junctions to picosecond voltage pulses

Description: Oxide superconductors with high critical temperature [Tc] make sensitive thermometers for several types of infrared bolometers. The authors built composite bolometers with YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta]] thermometers on sapphire substrates which have higher sensitivity than competing thermal detectors which operate at temperatures above 77 K. A 1 x 1 mm bolometer with gold black serving as the radiation absorber has useful sensitivity for wavelengths 20--100 [mu]m. A 3 x 3 mm bolomete… more
Date: May 1, 1993
Creator: Verghese, S.
Partner: UNT Libraries Government Documents Department
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Solid-state proton conductors

Description: The purpose of this program was to survey the field of solid-state proton conductors (SSPC), identify conductors that could be used to develop solid-state fuel cells suitable for use with coal derived fuel gases, and begin the experimental research required for the development of these fuel cells. This document covers the following topics: the history of developments and current status of the SSPC, including a review of proton conducting electrolyte structures, the current status of the medium … more
Date: December 1, 1990
Creator: Jewulski, J. R.; Osif, T. L. & Remick, R. J.
Partner: UNT Libraries Government Documents Department
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Study of selected off-gases produced during the immobilization of nuclear wastes in the SYNROC process. Final report for the year ended December 31, 1982

Description: The vaporization of cesium from the SYNROC mineral barium-cesium hollandite was studied over the temperature range 900/sup 0/C to 1150/sup 0/C using the transpiration method. With a dry argon-5% hydrogen carrier gas, the pressure of cesium over barium-cesium hollandite solid solution follows the relationship, log P/sub Cs/(atm) = 2.743 - 1.135 X 10/sup 4//T(K). The heat of vaporization is 217 +- 15 kJ/mole. The presence of water vapor increased the volatility of cesium.
Date: December 31, 1982
Creator: Carpenter, J.H.; McMullen, J.C.; Olmscheid, B.A. & Chezick, P.
Partner: UNT Libraries Government Documents Department
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Studies of nonlinear electrodynamics of high-temperature superconductors

Description: Nonlinear electrodynamics of high-{Tc} superconductors are studied both theoretically and experimentally. For powdered samples, a novel model is presented in which the metallographically observed superconducting grains in the powder are modeled as superconducting current loops of various areas with weak links. Surprising harmonic generation behavior in an arc field, H{sub 1} cos({omega}t), is predicted by the model; the power at high harmonics show sharp dips almost periodic in a superposing dc… more
Date: August 1, 1991
Creator: Lam, Quan-Chiu H.
Partner: UNT Libraries Government Documents Department
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Investigations on SYNROC mineralogy. Progress report

Description: Progress reports are presented for the following projects: (1) factors influencing the leaching performance of hollandiate; (2) incorporation of uranium and rare earths into zirconolite; (3) reconnaissance studies of the stability relations of Ca-Ti-Al phases in SYNROC C formulations; (4) immobilization of highly aluminous sludges; (5) SYNROC D formulations produced by sintering in air; (6) crystallization behavior of interstitial glass in SYNROC D formulations. Some of the highlights are: (1) … more
Date: January 21, 1982
Creator: Ringwood, A.E.
Partner: UNT Libraries Government Documents Department
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Environmental test program for superconducting materials and devices: Preliminary results of testing program at Savannah River Site

Description: The properties of YBa{sub 2}Cu{sub 3}O{sub 7-x} superconducting tapes designed and fabricated into SAFIRE-type, encapsulated, grounding links by the Ceramic Engineering Department at Clemson University are under investigation. Testing at the Savannah River Site will include gamma irradiation, vibration, and long-term evaluation. The gamma irradiation portion of testing has been completed. The long-term testing began in January and will continue. The vibration test has yet to be started.
Date: May 30, 1991
Creator: Randolph, H. (Westinghouse Savannah River Co., Aiken, SC (United States)) & Verebelyi, D. (Westinghouse Savannah River Co., Aiken, SC (United States) Clemson Univ., SC (United States))
Partner: UNT Libraries Government Documents Department
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Practical superconductor development for electrical power applications

Description: Development of useful high-critical-temperature (high-{Tc}) superconductors requires synthesis of superconducting compounds; fabrication of wires, tapes, and films from these compounds; production of composite structures that incorporate stabilizers or insulators; and design and testing of efficient components. This report describes technical progress of research and development efforts aimed at producing superconducting components based on the Y-Ba-Cu, Bi-Sr-Ca-Cu, Bi-Pb-Sr-Ca-Cu, and Tl-Ba-Ca… more
Date: October 1, 1991
Creator: Goretta, K.C. (comp.)
Partner: UNT Libraries Government Documents Department
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The study of structure-processing-property relations in copper oxide based high [Tc] superconductors

Description: Objective is investigation of critical current limiting processes in bulk superconductors. Since the grain boundaries play a key role here, we focus on the electrical characterization of single grain boundaries. Electrical contact to thin polished sections is established with thermosonic wire bonding. Laser cutting is used to isolate a single grain boundary. Results on YBa[sub 2]Cu[sub 3]O[sub x] showed that two different types of grain boundaries are present. Most grain boundaries showed curre… more
Date: June 1, 1993
Creator: Kingon, A. I.
Partner: UNT Libraries Government Documents Department
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Characterization of electrically conducting oxides

Description: This report discusses some of the highlights and publications of this years work. Listed below are the areas of interest and progress within the program: The studies of the Ba{sub 2}YCu{sub 3}O{sub 7-x} system have shown that the conduction processes (metallic or small polaron) have little temperature dependence and are almost entirely a function of oxygen stoichiometry. The substitution of 10 to 20 m% Ca and Co into LaCrO{sub 3} has enabled the system to be sintered to >95% TD at 1400{degree}C… more
Date: January 1, 1989
Creator: Anderson, H.U. & Sparlin, D.M.
Partner: UNT Libraries Government Documents Department
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Environmental test program for superconducting materials and devices

Description: The properties of YBa[sub 2]Cu[sub 3]O[sub 7-x] superconducting tapes designed and fabricated into SAFIRE-type, encapsulated, grounding links by the Ceramic Engineering Department at Clemson University were investigated (NASA Contract No. NAG-1-1127). Testing at the Savannah River Site included gamma irradiation, vibration, magnetic field, and long-term evaluation. Irradiation and vibration did not change the physical or electrical properties of the tested samples. An applied magnetic field of … more
Date: January 1, 1992
Creator: Randolph, H. & Verebelyi, D.
Partner: UNT Libraries Government Documents Department
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Positron studies of defected metals, metallic surfaces

Description: Specific problems proposed under this project included the treatment of electronic structure and momentum density in various disordered and defected systems. Since 1987, when the new high-temperature superconductors were discovered, the project focused extensively on questions concerning the electronic structure and Fermiology of high-[Tc] superconductors, in particular, (i) momentum density and positron experiments, (ii) angle-resolved photoemission intensities, (iii) effects of disorder and s… more
Date: January 1, 1991
Creator: Bansil, A.
Partner: UNT Libraries Government Documents Department
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ERDA/NASA Advanced Thermionic Technology Program. Progress report No. 25. Report No. TE4220/4233-14-78

Description: Progress is reported in the areas of (1) surface studies (surface theory, surface characterization chamber, activation chamber), (2) plasma studies (converter theory, enhanced mode conversion), (3) converter development (low-temperature conversion experiments, high-efficiency converter experiments), and (4) hot shell development. (WHK)
Date: July 1, 1977
Creator: Toy, A.
Partner: UNT Libraries Government Documents Department
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Hydrothermal investigation of SYNROC formulations from 150/sup 0/ to 610/sup 0/ at 100-MPa water pressure

Description: The static leaching behavior of seven formulations of SYNROC and two preparations of hollandite have been investigated under hydrothermal conditions. Each formulation was tested at several times (1 to 60 days) and temperatures (150 to 610/sup 0/C) at 100-MPa water pressure, using distilled water as the fluid. Both cored and powdered samples were employed in the hydrothermal experiments. Leach rates (g SYNROC/m/sup 2/ day) were calculated on the basis of element concentrations observed in the le… more
Date: December 1, 1980
Creator: Page, L. E.; Bazan, C.; Piwinskii, A. J.; Smith, G. S. & Wootton, S.
Partner: UNT Libraries Government Documents Department
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Mechanical and thermophysical properties of hot-pressed SYNROC B

Description: The optimal SYNROC compositons for use with commercial waste are reviewed. Large amounts of powder (about 2.5 kg) were prepared by convention al ceramic operations to test the SYNROC concept on a processing scale. Samples, 15.2 cm in diameter, were hot pressed in graphite, and representative samples were cut for microstructural evaluations. Measured mechanical and thermophysical properties did not vary significantly as a function of sample location and were typical of titanate ceramic materials. more
Date: May 6, 1981
Creator: Hoenig, C. L.; Newkirk, H. W.; Otto, R. A.; Brady, R. L.; Brown, A. E.; Ulrich, A. R. et al.
Partner: UNT Libraries Government Documents Department
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