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Arsenic Removal From Gaseous Streams

Description: Uranium feed materials, depending on the production process, have been found to contain arsenic (As) as a contaminant. Analyses show the As to be present as As pentafluoride (AsF{sub 5}) and/or hexafluoroarsenic acid (HAsF{sub 6}) and enter the enrichment cycle through contaminated hydrogen fluoride (HF). Problems related to corrosion of cylinder valves and plugging of feed lines and valves have been attributed to the As. Techniques to separate AsF{sub 5} from uranium hexafluoride (UF{sub 6}) u… more
Date: November 22, 1989
Creator: Russell, R. G. & Otey, M. G.
Partner: UNT Libraries Government Documents Department
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OTEC-1 power system test program: performance of one-megawatt heat exchangers

Description: Heat exchanger test results for the first deployment of OTEC-1 are reported. These tests were aimed at evaluating the performance of a state-of-the-art, 1-MWe titanium shell-and-tube evaporator and condenser in an ocean environment. The evaporator consisted of both a plain and an enhanced (Union Carbide High Flux) tube bundle, whereas the condenser had plain tubes only. All tests with the evaporator were conducted in the sprayed-bundle mode. Experimental results for the condenser and plain-tube… more
Date: November 1, 1981
Creator: Lorenz, J. J.; Yung, D.; Howard, P. A.; Panchal, C. B. & Poucher, F. W.
Partner: UNT Libraries Government Documents Department
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REFINEMENT OF THE NEPHELINE DISCRIMINATOR: RESULTS OF A PHASE II STUDY

Description: Twenty five glass compositions were selected for a Phase II study to assess the potential for reducing the conservatism in the nepheline discriminator. The glass compositions were restricted to regions that fell within the validation ranges of the DWPF PCCS models. In addition, the liquidus temperature model was used to restrict the glass compositions so that they could all be melted at the same temperature. The nepheline discriminator was used to force the glass compositions into regions where… more
Date: November 21, 2008
Creator: Fox, K & Tommy Edwards, T
Partner: UNT Libraries Government Documents Department
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(Tribology conferences and forums)

Description: The principal meeting attended during this trip was the Japan International Tribology Conference Nagoya 1990. The conference encompassed a wide range of topics, including the tribology of ceramics, the tribology in high-performance automobiles, and many aspects of lubrication technology. Associated forums were also held on the tribology of advanced ceramics, on solid lubrication, and on automotive lubricants. Presentations made during the latter forum discussed anticipated trends in engine deve… more
Date: November 30, 1990
Creator: Yust, C.S.
Partner: UNT Libraries Government Documents Department
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Chemical reduction of refractory oxides by atomic hydrogen

Description: The chemical reduction of UO/sub 2/ and Al/sub 2/O/sub 3/ by atomic hydrogen was studied. Results of the UO/sub 2//H investigation indicates that reduction of UO/sub 2/ by atomic hydrogen proceeds by the production of water vapor and hypostoichiometric urania. Water vapor and aluminum metal are formed in the Al/sub 2/O/sub 3//H system. The relative ease which UO/sub 2/ is reduced by atomic hydrogen compared with Al/sub 2/O/sub 3/ is due to two factors. The first is related to the thermochemistr… more
Date: November 1, 1978
Creator: Dooley, D.; Balooch, M. & Olander, D.R.
Partner: UNT Libraries Government Documents Department
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Thermal/chemical degradation of ceramic cross-flow filter materials

Description: This report summarizes the 14-month, Phase 1 effort conducted by Westinghouse on the Thermal/Chemical Degradation of Ceramic Cross-Flow Filter Materials program. In Phase 1 expected filter process conditions were identified for a fixed-bed, fluid-bed, and entrained-bed gasification, direct coal fired turbine, and pressurized fluidized-bed combustion system. Ceramic cross-flow filter materials were also selected, procured, and subjected to chemical and physical characterization. The stability of… more
Date: November 1, 1989
Creator: Alvin, M. A.; Lane, J. E. & Lippert, T. E.
Partner: UNT Libraries Government Documents Department
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Radio frequency heating of ceramic windows in fusion applications

Description: Ceramic windows will be used as material barriers for radio frequency plasma heating in fusion reactors. This report examines the theory behind rf heating phenomena. Heating calculations are presented for various window materials, thicknesses, wavelengths, and power densities. The most pertinent material properties are loss tangent, thermal conductivity, dielectric constant, strength, and radiation resistance. Calculations indicate that among candidate materials, beryllium oxide offers the most… more
Date: November 1, 1981
Creator: Fowler, J.D. Jr.
Partner: UNT Libraries Government Documents Department
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Support effects studied on model supported catalysts

Description: We are studying model catalysts in which the active phase is deposited onto flat oxide substrates in order to understand how a catalyst is affected by its support. We have examined the following growth and stability of titania overlayers which had been vapor deposited onto a Rh foil; the growth of Pt films on ZnO(0001)Zn and O(0001)O and compared the results to those obtained for Pt on {alpha}-Al{sub 2}O{sub 3}(0001). Samples were prepared by vapor deposition of Pt onto flat substrates in ultra… more
Date: November 1, 1991
Creator: Gorte, R.G.
Partner: UNT Libraries Government Documents Department
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Thermal shock of ceramic materials

Description: This report discusses a demonstration which is suitable for students in materials science at the high school or college levels. The demonstrations presents the concept of thermal shock in ceramic materials, and illustrates the pertinent factors of materials selection.
Date: November 1, 1991
Creator: Bunnell, L.R.
Partner: UNT Libraries Government Documents Department
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Irradiation performance of oxide dispersion strengthened copper alloys to 150 dpa at 415 degree C

Description: Results have been obtained on the post-irradiation properties of various oxide dispersion strengthened copper alloys irradiated from 34 to 150 dpa at 415{degrees}C in the Fast Flux Test Facility. The GlidCop alloys strengthened by Al{sub 2}O{sub 3} continue to outperform other alloys with respect to swelling resistance, and retention of both electrical conductivity and yield strength. Several castable ODS alloys and a Cr{sub 2}O{sub 3}-strengthened alloy show increasingly poor resistance to rad… more
Date: November 1, 1991
Creator: Edwards, D.J.; Kumar, A.S. (Missouri Univ., Rolla, MO (United States)); Anderson, K.R.; Stubbins, J.F. (Illinois Univ., Urbana, IL (United States)); Garner, F.A. & Hamilton, M.L. (Pacific Northwest Lab., Richland, WA (United States))
Partner: UNT Libraries Government Documents Department
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Preparation and characterization of hydrogenated amorphous silicon thin films and thin film solar cells produced by ion plating techniques. Third quarterly progress report, July 1-September 30, 1979

Description: Using quartz, sapphire and stainless steel substrates, hydrogenated a-Si films have been prepared by ion-plating techniques through a 1000 to 2000 volt hydrogen glow. The highest hydrogen content to date has been 18 a/o in a film evaporated in partial pressure of 55 ..mu.. of hydrogen. Optical band gaps of these films varied from 1.67 eV to 2.21 eV. Films made on sapphire substrates were used in IR-spectroscopy measurement; they had a doublet absorption peak at approximately 2000 cm/sup -1/ cor… more
Date: November 1, 1979
Creator: Cocks, F H; Jones, P L; Dimmey, L & Cogan, S F
Partner: UNT Libraries Government Documents Department
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Cross-flow, filter-sorbent catalyst for particulate, SO sub 2 and NO sub x control

Description: The device described in this report will simultaneously remove particulates, SO{sub 2} and NO{sub x} from the combustion gases of coal combustors. The device is configured as a cross-flow filter. The gas flows from the inlet passages to orthogonally oriented discharge channels via thin, multilayered porous walls. Flue gas enters from both the front and back of the device. With the left wall of the filter sealed, gas discharges from the right side of the device. The key to combined physical (fly… more
Date: November 1, 1990
Partner: UNT Libraries Government Documents Department
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Thermionic Technology Program: A, Insulator test and evaluation: Final report

Description: The Thermionic Technology Program (TTP) consisted of two major efforts, evaluation of insulators and evaluation of thermionic converters. This report details the work performed on the insulator phase of the program. Efforts were made to better understand the mechanisms involved in the electrochemistry of insulators at elevated temperatures by modelling the ionic transport through the various layers of the insulator package. Although rigorous analytic solutions could not be obtained owing to a l… more
Date: November 30, 1987
Creator: Dobson, J.C. & Witt, T.
Partner: UNT Libraries Government Documents Department
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High power CW performance from a Ti:Sapphire laser and a single-pass amplifier

Description: Using two argon-ion lasers to pump a CW Ti:Sapphire laser we have demonstrated consistent high power (19 watts) operation with a low order spatial mode. Thermal lensing effects were controlled by enclosing the laser in a vacuum and cooling the rod with liquid nitrogen. Using this laser we also demonstrated a CW Ti:Sapphire amplifier with an efficiency of 20%. 5 refs., 5 figs.
Date: November 7, 1990
Creator: Erbert, G. V.; Bass, I. L.; Hackel, R. P.; Jenkins, S.; Kanz, K. V. & Paisner, J. A.
Partner: UNT Libraries Government Documents Department
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High Temperature Alkali Corrosion of Ceramics in Coal Gas

Description: High temperature alkali corrosion has been known to cause premature failure of ceramic components used in advanced high temperature coal combustion systems such as coal gasification and clean-up, coal fired gas turbines, and high efficiency heat engines. The objective of this program is to systematically evaluate the alkali corrosion resistance of the most commonly used structural ceramics including silicon carbide, silicon nitride, cordierite, mullite, alumina, aluminum titanate, zirconia, and… more
Date: November 30, 1991
Creator: Pickrell, G. R.; Sun, T. & Brown, J. J.
Partner: UNT Libraries Government Documents Department
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Direct conversion of methane to C sub 2 's and liquid fuels

Description: Objectives of the project are to discover and evaluate novel catalytic systems for the conversion of methane or by-product light hydrocarbon gases either indirectly (through intermediate light gases rich in C{sub 2}'s) or directly to liquid hydrocarbon fuels, and to evaluate, from an engineering perspective, different conceptualized schemes. The approach is to carry out catalyst testing on several specific classes of potential catalysts for the conversion of methane selectively to C{sub 2} prod… more
Date: November 22, 1989
Creator: Warren, B.K. & Campbell, K.D.
Partner: UNT Libraries Government Documents Department
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Preliminary investigations of thermionic converters utilizing HOTEMA and DFVLR electrodes

Description: Experiment results obtained from three thermionic converters using improved electrodes are reported. Two converters with ZrO/sub 2/-Mo cermet electrodes produced by a low pressure plasma spray technique at the DFVLR in Stuttgart were fabricated and tested. The first of this pair of diodes was outgassed and operated at high temperatures and did not show improved thermionic performance. The second of the two was outgassed and operated at more moderate temperatures. An encouraging barrier index of… more
Date: November 1, 1982
Creator: Saunders, M.; Danielson, L. & Huffman, F.
Partner: UNT Libraries Government Documents Department
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Evaluation of Advanced Materials: Final Report

Description: Cemented tungsten carbides with a binder level in the range of 5 to 6 percent exhibited the best resistance to erosion for this class of materials. Other practical cermet meterials were diamond - Si/SiC, Al/sub 2/O/sub 3/-B/sub 4/C-Cr, and B/sub 4/C-Co. SiAlON exhibited erosion resistance equivalent to the best WC-cermet. The only coating system to show promise of improved erosion resistance was CVD TiB/sub 2/ on cemented TiB/sub 2/-Ni. Cracking and/or spalling of a TiC coating and a proprietar… more
Date: November 18, 1982
Creator: Wright, I. G.; Clauer, A. H.; Shetty, D. K.; Tucker, T. R. & Stropki, J. T.
Partner: UNT Libraries Government Documents Department
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MHD air heater development technology. Technical progress report, July 1-September 30, 1980

Description: The technology development of the directly-fired high temperature air heater (HTAH) for MHD power plants is described. Progress is reported on the three tasks. The first task is materials selection, evaluation, and development. The objective of this task is to continue development of ceramic materials technology for the directly-fired HTAH. Task two is operability, performance, and materials testing. The objectives of this task are to demonstrate the technical feasibility of operating a directl… more
Date: November 1, 1980
Partner: UNT Libraries Government Documents Department
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Manufacturing tailored property ceramic composites

Description: Composite materials are desirable for many advanced engineering applications where the properties of a single phase material cannot meet all of the service requirements; however, existing process technology has limited the development and commercialization of composites. Lack of reproducible sintering to high density is one of the major obstacles to commercializing ceramic composites. Final-stage, non-reactive liquid phase sintering (NLPS) theory provides metrics for sinterability that can be u… more
Date: November 14, 1994
Creator: Ewsuk, K. G. & Harrison, L. W.
Partner: UNT Libraries Government Documents Department
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High temperature alkali corrosion of ceramics in coal gas. Quarterly progress report No. 1, September 1, 1991--November 31, 1991

Description: High temperature alkali corrosion has been known to cause premature failure of ceramic components used in advanced high temperature coal combustion systems such as coal gasification and clean-up, coal fired gas turbines, and high efficiency heat engines. The objective of this program is to systematically evaluate the alkali corrosion resistance of the most commonly used structural ceramics including silicon carbide, silicon nitride, cordierite, mullite, alumina, aluminum titanate, zirconia, and… more
Date: November 30, 1991
Creator: Pickrell, G. R.; Sun, T. & Brown, J. J.
Partner: UNT Libraries Government Documents Department
open access

Thermal shock of ceramic materials

Description: This report discusses a demonstration which is suitable for students in materials science at the high school or college levels. The demonstrations presents the concept of thermal shock in ceramic materials, and illustrates the pertinent factors of materials selection.
Date: November 1, 1991
Creator: Bunnell, L. R.
Partner: UNT Libraries Government Documents Department
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Summary report, Flexible VSR`s and VSR channel sleeve development programs

Description: (VSR = vertical safety rod.) This report summarizes results of development programs which have evaluated vertical rod channel sleeving materials and provided flexible vertical rods, acceptable for both interim use before rod channel sleeving, and for subsequent use in sleeved channels. B{sub 4}C is the rod material; graphite and Al oxide are among the sleeve materials.
Date: November 15, 1963
Creator: Kempf, F. J.
Partner: UNT Libraries Government Documents Department
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High-temperature corrosion in advanced combustion systems

Description: Conceptual designs of advanced combustion systems that utilize coal as a feedstock require high temperature furnaces and heat transfer surfaces capable of operation at much elevated temperatures than those prevalent in current coal-fired power plants. The combination of elevated temperatures and hostile combustion environments necessitate development/application of advanced ceramic materials in these designs. The present paper characterizes the chemistry of coal-fired combustion environments ov… more
Date: November 1, 1993
Creator: Natesan, K.; Yanez-Herrero, M. & Fornasieri, C.
Partner: UNT Libraries Government Documents Department
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