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High-temperature electrically conductive ceramic composite and method for making same

Description: The present invention relates to a metal-oxide ceramic composition useful in induction heating applications for treating uranium and uranium alloys. The ceramic composition is electrically conductive at room temperature and is nonreactive with molten uranium. The composition is prepared from a particulate admixture of 20 to 50 vol. % niobium and zirconium oxide which may be stabilized with an addition of a further oxide such as magnesium oxide, calcium oxide, or yttria. The composition is prepared by blending the powders, pressing or casting the blend into the desired product configuration, and then sintering the casting or compact in an inert atmosphere. In the casting operation, calcium aluminate is preferably added to the admixture in place of a like quantity of zirconia for providing a cement to help maintain the integrity of the sintered product.
Date: June 9, 1981
Creator: Beck, D.E.; Gooch, J.G.; Holcombe, C.E. Jr. & Masters, D.R.
Partner: UNT Libraries Government Documents Department

Design and test of-80 kV snubber core assemblies for MFTF sustaining-neutral-beam power supplies

Description: Core snubbers, located near the neutral beam source ends of the Mirror Fusion Test Facility (MFTF) Sustaining Neutral Beam Power Supply System (SNBPSS) source cables, protect the neutral beam source extractor grid wires from overheating and sputtering during internal sparkdowns. The snubbers work by producing an induced counter-emf which limits the fault current and by absorbing the capacitive energy stored on the 80 kV source cables and power supplies. A computer program STACAL was used in snubber magnetic design to choose appropriate tape wound cores to provide 400 ..cap omega.. resistance and 25 J energy absorption. The cores are mounted horizontally in a dielectric structure. The central source cable bundle passes through the snubber and terminates on three copper buses. Multilam receptacles on the buses connect to the source module jumper cables. Corona rings and shields limit electric field stresses to allow close clearances between snubbers. A filament circuit shunt bias winding wound on a dielectric cylinder surrounds the cores. The dc voltage holdoff of a single snubber has been tested. Current and voltage behavior during capacitor bank and source cable discharges are presented.
Date: October 9, 1981
Creator: Bishop, S.R.; Mayhall, D.J.; Wilson, J.H.; De Vore, K.R.; Ross, R.I. & Sears, R.G.
Partner: UNT Libraries Government Documents Department

Application of microfabrication technology to thermionic energy conversion. Progress report No. 6, November 1, 1980-January 31, 1981

Description: Effort was directed toward the fabrication of a micron-spaced thermionic converter diode. This technique demonstrated that interelectrode spacings down to 1.5 ..mu..m could be obtained. Several methods of duplicating the emitter and collector surfaces were also investigated. Two new techniques are proposed; both stem from an earlier idea of using evaporation, photolithography, and etching techniques. These two fabrication methods yielded a one-piece diode structure with a thick-film copper collector, eliminating the need to physically duplicate the electrode surfaces and realign the electrodes. Effort has also been directed toward a more detailed theoretical analysis of micron-spaced thermionic converter performance. Taking into account heat losses through the interelectrode support structure, it is likely that the maximum energy conversion efficiency may be greatest at a spacing somewhat larger than 1 micron (..mu..m), but less than 10 ..mu..m.
Date: March 9, 1981
Creator: Brodie, I.; Shepherd, C. & Spindt, C.A.
Partner: UNT Libraries Government Documents Department

Design, fabrication, and testing of the magnet liner supports for the Mirror Fusion Test Facility

Description: Heat is radiated from both the vacuum vessel that houses the magnet and the heated plasma that exists at the central region of the magnets. Approximately 30 kW of heat will be transmitted to the 311 m/sup 2/ of magnet surface area from these two heat sources. We can reduce this heat load substantially by installing liquid nitrogen (LN)-filled panels around the magnets to counteract the 300/sup 0/K vessel wall temperature. When flowing the LN inside the panels, the temperature drops to 85/sup 0/K. These LN panels also serve as thermal protection for the helium pipings in the MFTF magnet system. However, near the plasma where a higher heat load is generated, we must add water panels to protect the LN panels. All the LN panels, water panels, and their manifoldings are called the magnet liners. Of the total of 344 pieces, 240 are used directly on the magnets. The support system that mounts these LN liner panels on the magnets is the topic of this paper.
Date: October 9, 1981
Creator: Chang, Y.
Partner: UNT Libraries Government Documents Department

Magnet and conductor developments for the Mirror Fusion Program

Description: The conductor development and the magnet design and construction for the MFTF are described. Future plans for the Mirror Program and their influence on the associated superconductor development program are discussed. Included is a summary of the progress being made to develop large, high-field, multifilamentary Nb/sub 3/Sn superconductors and the feasibility of building a 12-T yin-yang set of coils for the machine to follow MFTF. In a further look into the future, possible magnetic configurations and requirements for mirror reactors are surveyed.
Date: October 9, 1981
Creator: Cornish, D.N.
Partner: UNT Libraries Government Documents Department

Design of 12-T Yin-Yang magnets operating in subcooled, superfluid helium. [Nb-Ti and Nb/sub 3/Sn]

Description: A conceptual design study of a large 12-T yin-yang pair of coils, typical of the plug coils envisioned for a tandem-mirror facility to follow MFTF, has been completed. Because of its larger size and field strength, the magnetic forces are much greater than those experienced on MFTF. The main purpose of this study, therefore, is to assess the feasibility of such a device, paying particular attention to mechanical stress and conductor strain. The conductor proposed operates at 15.6 kA and consists of a rectangular half-hard copper stabilizer with a Nb-Ti insert in the low-field regions and Nb/sub 3/Sn in the high field. The coil is divided into four sections in the longitudinal direction, with steel substructure to limit the winding stress to an acceptable level. The conductor is cryostatically stabilized in superfluid He at 1.8K and 1.2 atm, with an operating heat flux of 0.8 W.cm/sup -2/.
Date: October 9, 1981
Creator: Cornish, D.N.; Hoard, R.W. & Baldi, R.
Partner: UNT Libraries Government Documents Department

[Clipping: "Falwell and the court", Dallas Times Herald]

Description: Clipping from an article in the Dallas Times Herald, dated Thursday, July 9, 1981. The article is an anonymous editorial or opinion piece opposing the Rev. Jerry Falwell's influence on the appointment of Supreme Court justices. The author specifically refers to Falwell's objection to President Reagan's nomination of Sandra Day O'Connor.
Date: July 9, 1981
Creator: Dallas Times Herald
Partner: UNT Libraries Special Collections

Hydrothermal energy development projects

Description: The development of hydrothermal energy for direct heat applications is being accelerated by twenty-two demonstration projects that are funded on a cost-sharing basis by the US Department of Energy, Division of Geothermal Energy. These projects are designed to demonstrate the technical and economic feasibility of the direct use of hydrothermal resources in the United States. Engineering and economic data for the projects are summarized. The data and experience being generated by these projects will serve as an important basis for future direct heat development.
Date: March 9, 1981
Creator: DiBello, E.G.
Partner: UNT Libraries Government Documents Department

Gasification research on wood grow project

Description: The GROW (Gasification Research on Wood) project consists of a research project on thermochemical degradation of wood particles (sawdust or hammermilled wood) on a pilot plant scale and utilizes a 100 cm (40 in.) diameter fluidized sand bed reactor at capacities of up to 1000 Kg/Hr (2200 lb/hr). Supplementary facilities include wood preparation and air conveying, a wood feed bin, feed and transfer screws, an air compressor with storage and filter tanks, an electrical preheater, a propane-fired preheater, a cyclone separator removing solids from product gas, a water scrubber to cool and clean product gas, a scrubber wate settling tank, a scrubber water cooler, a knockout drum, a demister to be installed in the future, a recycle compressor for recirculation, a recycle gas storage tank, a flare and stack with air blower to dispose of the gas, 2 CO/sub 2/ stripper columns to be installed in the future to remove CO/sub 2/ by caustic adsorption, caustic tanks, and the necessary piping, pumps, sampling, and measurement facilities. A brief report of progress on the project is given, followed by the safety implementation plan and operating, maintenance, and safety procedures. (MHR)
Date: January 9, 1981
Creator: Flanigan, V J
Partner: UNT Libraries Government Documents Department

Head assembly for multiposition borehole extensometer

Description: A head assembly for a borehole extensometer and an improved extensometer for measuring subsurface subsidence. A plurality of inflatable anchors provide discrete measurement points. A metering rod is fixed to each of the anchors which are displaced when subsidence occurs, thereby translating the attached rod. The head assembly includes a sprocket wheel rotatably mounted on a standpipe and engaged by a chain which is connected at one end to the metering rod and at the other end to a counterweight. A second sprocket wheel connected to the standpipe also engages the chain and drives a connected potentiometer. The head assembly converts the linear displacement of the metering rod to the rotary motion of the second sprocket wheel, which is measured by the potentiometer, producing a continuous electrical output.
Date: June 9, 1981
Creator: Frank, D.N.
Partner: UNT Libraries Government Documents Department

Neutron-source characterization and radiation-damage calculations for material studies

Description: In our quest to understand radiation damage in materials, it is vital that we characterize radiation sources in terms of neutron flux and spectra as well as the more-fundamental displacement damage, gas production, and transmutation rates. Such data are crucial to correlations of materials-property changes in different environments and to predictions of materials performance in inaccessible environments, such as fusion reactors. Dosimetry techniques have been developed to measure the neutron flux and spectra in diverse facilities including thermal, fast, and mixed reactors, T (d,n) and Be (d,n) accelerator sources, and high-energy spallation sources. Displacement-damage cross sections have been calculated for 36 elements spanning the periodic table. All of these exposure parameters can now be routinely measured with 10 to 15% relative accuracy at all existing radiation-effect facilities. 4 tables.
Date: November 9, 1981
Creator: Greenwood, L.R.
Partner: UNT Libraries Government Documents Department

Tensile properties of 20% cold-worked titanium-modified type 316 stainless steel irradiated in HFIR

Description: An alloy of type 316 stainless steel with the addition of 0.23% Ti (316 + Ti) has been irradiated in the 20% cold-worked condition in the HFIR (a mixed fast and thermal neutron spectrum reactor) and tested near the irradiation temperature in the range of 300 to 600/sup 0/C. Tensile tests were performed following irradiation to fluence levels of 0.63 to 2.1 x 10/sup 26/ n/m/sup 2/ (E > 0.1 MeV) and helium levels of 200 to 1000 at. ppM. The 316 + Ti exhibited higher strength and lower ductility than similarly irradiated type 316 stainless steel (316 SS). However, the tensile elongation of 316 + Ti tends to saturate with increasing fluence at 575/sup 0/C whereas the elongation of 316 SS continues to fall for the fluences investigated. Reduction of area is similar for the two alloys, and 316 + Ti shows completely ductile rupture at 450/sup 0/C and below. The differences in strength and ductility are attributed to the influence of TiC precipitates trapping helium in the matrix.
Date: August 9, 1981
Creator: Grossbeck, M.L. & Maziasz, P.J.
Partner: UNT Libraries Government Documents Department

Review and evaluation of NASAP proliferation assessment activities. Final report

Description: Assessing proliferation resistance of nuclear power alternatives was central to the Nonproliferation Alternative System Assessment Program (NASAP). Assessment efforts were made by several organizations associated with NASAP. These efforts produced papers and documents which assisted the NASAP program understand the many facets of the proliferation problem and carry out its responsibilities of providing R and D guidance. This report briefly reviews these papers to document the chronology of the process, to observe the evolution of the assessment effort and to identify additional efforts which might be appropriate even though NASAP is complete.
Date: January 9, 1981
Creator: Hammelman, J.E. & Outlaw, D.A.
Partner: UNT Libraries Government Documents Department

Personnel neutron dosimetry studies at the Lawrence Livermore National Laboratory

Description: A study was conducted to determine the effect of phantom size, shape and composition on the response of an albedo neutron dosimeter. The most important feature was the shape. The dose equivalent rate from a californium neutron source was determined. Ten different dose rates were determined which varied from 2.39 to 3.02 rem/h for the CF source used. (ACR)
Date: June 9, 1981
Creator: Hankins, D.E.
Partner: UNT Libraries Government Documents Department

Magnetron co-sputtering system for coating ICF targets

Description: Fabrication of Inertial Confinement Fusion (ICF) targets requires deposition of various types of coatings on microspheres. The mechanical strength, and surface finish of the coatings are of concern in ICF experiments. The tensile strength of coatings can be controlled through grain refinement, selective doping and alloy formation. We have constructed a magnetron co-sputtering system to produce variable density profile coatings with high tensile strength on microspheres.
Date: September 9, 1981
Creator: Hsieh, E.J.; Meyer, S.F.; Halsey, W.G.; Jameson, G.T. & Wittmayer, F.J.
Partner: UNT Libraries Government Documents Department

Magnetron co-sputtering system for coating ICF targets

Description: Fabrication of Inertial Confinement Fusion (ICF) targets requires deposition of various types of coatings on microspheres. The mechanical strength, and surface finish of the coatings are of concern in ICF experiments. The tensile strength of coatings can be controlled through grain refinement, selective doping and alloy formation. We have constructed a magnetron co-sputtering system to produce variable density profile coatings with high tensile strength on microspheres. The preliminary data on the properties of a Au-Cu binary alloy system by SEM and STEM analysis is presented.
Date: December 9, 1981
Creator: Hsieh, E.J.; Meyer, S.F.; Halsey, W.G.; Jameson, G.T. & Wittmayer, F.J.
Partner: UNT Libraries Government Documents Department

[News Clip: Alcohol]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: February 9, 1981, 5:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: American]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story that aired at 10 PM.
Date: September 9, 1981
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Location Info:
Partner: UNT Libraries Special Collections

[News Clip: Arlington RR]

Description: Video footage from the NBC 5/KXAS station in Fort Worth, Texas, to accompany a news story. This B-Roll footage features railroad tracks. This footage was shot for the 5:00 P.M. news broadcast.
Date: July 9, 1981, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Avon tennis]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: March 9, 1981, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections