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The development of precipitated iron catalysts with improved stability

Description: The objective of this program is to identify the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and to use these chemical principles in the design of catalysts suitable for slurry reactors. The performance targets are 88% CO+H{sub 2} conversion with less than 1% deactivation/day for 1 month and a methane and ethane selectivity of no more than 7% (based on hydrocarbons and oxygenates only) at a space velocity of at least 2 normal liters per hr per gram iron (NL/hr/gFe) using a synthesis gas with 0.5-1.0 H{sub 2}:CO ratio in a slurry reactor.
Date: May 6, 1992
Creator: Abrevaya, H.
Partner: UNT Libraries Government Documents Department
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Compatibility testing of vitrified waste forms

Description: An experimental program to evaluate candidate metals for use in the fabrication of canisters for long-term storage of vitrified radioactive wastes is described. The long-term compatibility of the candidate metal both with the contained vitrified radioactive waste and with the external environments expected in possible final storage locations will be determined. These tests involve heating combinations of waste forms and canister metals in intimate contact for up to 50,000 hr to accelerate any reactions that occur.
Date: March 6, 1978
Creator: Rankin, W.N.
Partner: UNT Libraries Government Documents Department
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Joining of ceramics for high performance energy systems. Mid-term progress report, August 1, 1979-March 31, 1980

Description: The subject program is primarily an exploratory and demonstration study of the use of silicate glass-based adhesives for bonding silicon-base refractory ceramics (SiC, Si/sub 3/N/sub 4/). The projected application is 1250 to 2050/sup 0/F relaxing joint service in high-performance energy conversion systems. The five program tasks and their current status are as follows. Task 1 - Long-Term Joint Stability. Time-temperature-transformation studies of candidate glass adhesives, out to 2000 hours simulated service exposure, are half complete. Task 2 - Environmental and Service Effects on Joint Reliability. Start up delayed due to late delivery of candidate glass fillers and ceramic specimens. Task 3 - Viscoelastic Damping of Glass Bonded Ceramics. Promising results obtained over approximately the same range of glass viscosity required for joint relaxation function (10/sup 7.5/ to 10/sup 9.5/ poise). Work is 90% complete. Task 4 - Crack Arrest and Crack Diversion by Joints. No work started due to late arrival of materials. Task 5 - Improved Joining and Fabrication Methods. Significant work has been conducted in the area of refractory pre-glazing and the application and bonding of high-density candidate glass fillers (by both hand-artisan and slip-spray techniques). Work is half complete.
Date: October 6, 1980
Creator: Smeltzer, C E & Metcalfe, A G
Partner: UNT Libraries Government Documents Department
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Distribution of calcretes and gypcretes in southwestern United States and their uranium favorability, based on a study of deposits in Western Australia and South West Africa (Namibia)

Description: Calcrete, dolocrete, and gypcrete carnotite are abundant in western Australia and Namib Desert, although only a few are of ore grade. The geology of these deposits are described. A genetic classification of calcretes emphasizing uranium favorability was developed, based on the distinction between pedogenic and nonpedogenic processes. Similarities between western Australia and South West Africa give support for the conclusions that lateral transport of U in groundwater is essential to ore deposition and that bedrock barriers or constrictions which narrow the channel of subsurface flow or force the water close to the land surface, greatly favor the formation of uraniferous calcretes. Criteria for uranium favorability deduced from the Australian and South West African studies were applied in a preliminary way to the southern Basin and Range Province of U.S. The procedure is to search for areas in which nonpedogenic calcrete or gypcrete may have developed. A caliche distribution map was compiled from soil survey and field data. Many areas were visited and some of the more interesting are described briefly, including parts of Clark County, Nevada, with occurrences of carnotite in calcrete. (DLC)
Date: January 6, 1978
Creator: Carlisle, D.; Merifield, P.M.; Orme, A.R.; Kohl, M.S.; Kolker, O. & Lunt, O.R.
Partner: UNT Libraries Government Documents Department
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TIBER (Tokamak Ignition/Burn Experimental Reactor) II as a precursor to an international thermonuclear experimental reactor

Description: The Tokamak Ignition/Burn Experimental Reactor (TIBER) was pursued in the US as one option for an International Thermonuclear Experimental Reactor (ITER). This concept evolved from earlier work on the Tokamak Fusion Core Experiment (TFCX) to develop a small, ignited tokamak. While the copper-coil versions of TFCX became the short-pulsed, 1.23-m radius, Compact Ignition Tokamak (CIT), the superconducting TIBER with long pulse or steady state and a 2.6-m radius was considered for international collaboration. Recently the design was updated to TIBER II, to accommodate more conservative confinement scaling, double-poloidal divertors for impurity control, steady-state current drive, and nuclear testing. 18 refs., 1 fig.
Date: April 6, 1988
Creator: Henning, C.D. & Gilleland, J.R.
Partner: UNT Libraries Government Documents Department
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Kinetics of the radiation-induced exchange reactions of H/sub 2/, D/sub 2/, and T/sub 2/: a review

Description: Mixtures of H/sub 2/--T/sub 2/ or D/sub 2/--T/sub 2/ will exchange to produce HT or DT due to catalysis by the tritium ..beta.. particle. The kinetics of the reaction D/sub 2/ + T/sub 2/ = 2DT may play an important role in designing liquid or solid targets of D/sub 2/--DT--T/sub 2/ for implosion fusion, and distillation schemes for tritium cleanup systems in fusion reactors. Accordingly, we have critically reviewed the literature for information on the kinetics and mechanism of radiation-induced self-exchange reactions among the hydrogens. We found data for the reaction H/sub 2/ + T/sub 2/ = 2HT in the gas phase and developed a scheme based on these data to predict the halftime to equilibrium for any gaseous H/sub 2/ + T/sub 2/ mixture at ambient temperature with an accuracy of +-10 percent. The overall order of the H/sub 2/ + T/sub 2/ = 2HT reaction is 1.6 based on an initial rate treatment of the data. The most probable mechanism for radiation-induced self-exchange reaction is an ion-molecule chain mechanism.
Date: January 6, 1978
Creator: Pyper, J.W. & Briggs, C.K.
Partner: UNT Libraries Government Documents Department
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Shiva automatic alignment systems: a brief description

Description: A diagram is given of the basic Shiva alignment system. The alignment requirements, as originally specified and as preseently estimated, together with the performance obtained to date from the prototype equipment are described. It is expected that this performance will be satisfactory for even the most alignment-sensitive targets and significantly better than is needed for experiments not requiring highly uniform illumination. The hardware arrangement planned for a typical Shiva chain is shown.
Date: September 6, 1977
Creator: Bliss, E. S.; Summers, M. A.; Cody, R. L.; Boyd, R. D. & Wintemute, J. D.
Partner: UNT Libraries Government Documents Department
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[News Script: Track]

Description: Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 6, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections
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[News Script: F-111]

Description: Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 6, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections
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