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A unified theory of resonant excitation of kinetic ballooning modes by energetic ions/alpha particles in tokamaks

Description: A complete theory of wave-particle interactions is presented whereby both circulating and trapped energetic ions can destabilize kinetic ballooning modes in tokamaks. Four qualitatively different types of resonances, involving wave-precessional drift, wave-transit, wave-bounce, and precessional drift-bounce interactions, are identified, and the destabilization potential of each is assessed. For a characteristic slowing-down distribution function, the dominant interaction is that which taps thos… more
Date: October 1, 1991
Creator: Biglari, H. & Chen, L.
Partner: UNT Libraries Government Documents Department
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Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties

Description: Several new types of silicon-containing preceramic polymers, i.e., poly(diorganosilacetylene) and poly(diorganosilvinylene) have been synthesized with molecular weights from 10,000 to 120,000. These polymers could be thermally converted to SiC with a moderate to high char yields. Ready solubility and good processability made these types of polymers attractive in their applications to ceramics. The thermal polymerization of diethynyldiphenyl-silane, which was reported in 1968 to afford poly(diph… more
Date: October 7, 1991
Creator: Pang, Yi.
Partner: UNT Libraries Government Documents Department
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The interpretation of reflectometry measurements of plasma fluctuations

Description: Wave reflections from density fluctuations with magnitudes and frequencies typical of drift waves have been investigated. Both drift waves and the reflected phase and amplitude depend on the density gradient scale length, and this common feature implies that both the angular deviation of a normally propagating wave and the phase change on reflection are of order unity. Thus the surface will always appear rough'' and amplitude variations will always be large. For smaller amplitude waves numerica… more
Date: October 1, 1991
Creator: Bretz, N.
Partner: UNT Libraries Government Documents Department
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Thermodynamic model for calorimetric and phase coexistence properties of coal derived fluids

Description: On September 1, 1989 work was initiated on a project to extend the available vapor-liquid equilibrium (VLE) model for coal fluids to allow satisfactory predictions of excess enthalpies of coal liquids at high pressures. The available vapor liquid equilibrium model was developed with support from previous grant from DOE-PETC (Grant no. DE-FG22-89PC90541). The current project also involves measurement of some model compound VLE data and chromatographic characterization of coal liquids for distrib… more
Date: October 1, 1991
Creator: Kabadi, V. N.
Partner: UNT Libraries Government Documents Department
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Research in theoretical nuclear physics

Description: The work done during the past year covers three separate areas, low energy nuclear reactions intermediate energy physics, and nuclear structure studies. This manuscript summarizes our achievements made in these three areas.
Date: October 1, 1991
Creator: Udagawa, T.
Partner: UNT Libraries Government Documents Department
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Investigations of CuInSe sub 2 Thin Films and Contacts

Description: This report describes research into electrical contacts for copper indium diselenide (CuInSe{sub 2}) polycrystalline thin films used for solar cell applications. Molybdenum contacts have historically been the most promising for heterojunction solar cells. This program studied contact stability by investigating thermally induced bilayer reactions between molybdenum and copper, indium, and selenium. Because selenization is widely used to fabricate CuInSe{sub 2} thin films for photovoltaic cells, … more
Date: October 1, 1991
Creator: Nicolet, M. A.
Partner: UNT Libraries Government Documents Department
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Cationically polymerizable monomers derived from renewable sources

Description: The objective of this project is to make use of products obtained from renewable plant sources as monomers for the direct production of polymers which can be used for a wide range of plastic applications. In this report is described progress in the synthesis and polymerization of cationically polymerizable monomers and oligomers derived from botanical oils, terpenes, natural rubber, and lignin. Nine different botanical oils were obtained from various sources, characterized and then epoxidized. … more
Date: October 1, 1991
Creator: Crivello, J. V.
Partner: UNT Libraries Government Documents Department
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Theoretical study of the structure, energetics, and dynamics of silicon and carbon systems using tight-binding approaches

Description: Semiempirical interatomic potentials are developed for silicon and carbon by modeling the total energy of the system using tight-binding approaches. The parameters of the models were obtained by fitting to results from accurate first-principles Local Density Functional calculations. Applications to the computation of phonons as a function of volume for diamond-structured silicon and carbon and the thermal expansions for silicon and diamond yields results which agree well with experiment. The ph… more
Date: October 25, 1991
Creator: Xu, Chunhui.
Partner: UNT Libraries Government Documents Department
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FY 1992 task plans for the Hanford Environmental Dose Reconstruction Project

Description: Phase 1 of the HEDR Project was designed to develop and demonstrate a method for estimating radiation doses people may have received from Hanford Site operations since 1944. The method researchers developed relied on a variety of measured and reconstructed data as input to a modular computer model that generates dose estimates and their uncertainties. As part of Phase 1, researchers used the reconstructed data and computer model to calculate preliminary dose estimates for populations from limit… more
Date: October 1, 1991
Partner: UNT Libraries Government Documents Department
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Ion-optical studies for improved ion transmission in multistage isotope-ratio mass spectrometers

Description: Theoretical and experimental ion-optical studies of multistage isotope-ratio mass spectrometers were conducted to determine what improvement in ion transmission efficiency might be attainable through design changes. The computer program GIOS (General Ion Optical Systems) was used to perform theoretical calculations of focusing properties and ion transmission efficiency. Actual transmission through multiple-sector instruments was determined from measurements of the ion beam vertical profile at t… more
Date: October 1, 1991
Creator: Stoffels, J.J. (Pacific Northwest Lab., Richland, WA (United States)) & Laue, H.J. (Purdue Univ., Lafayette, IN (United States))
Partner: UNT Libraries Government Documents Department
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Electric power monthly, October 1991. [CONTAINS GLOSSARY]

Description: This publication provides monthly statistics at the national, Census division, and State levels for net generation, fuel consumption, fuel stocks, quantity and quality of fuel, cost of fuel, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fuel are also displayed at the North American Electric Reliability Council (NERC) region level. Additionally, statistics at the company and plant … more
Date: October 11, 1991
Partner: UNT Libraries Government Documents Department
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Petroleum marketing monthly, October 1991. [Contains glossary]

Description: This report is designed to give information and statistical data about a variety of crude oils and refined petroleum products. The publication provides statistics on crude oil costs and refined petroleum products sales for use by industry, government, private sector analysts, educational institutions, and consumers. Data on crude oil include the domestic first purchase price, the f.o.b. and landed cost of imported crude oil, and the refiner's acquisition cost of crude oil. Sales data for motor … more
Date: October 10, 1991
Partner: UNT Libraries Government Documents Department
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Manual for COMSYN: A orbit integration code for the study of beam dynamics in compact synchrotrons

Description: COMSYN is a numerical integration code which is written for the study and design of the compact synchrotrons. An improved 4th-order Runge-Kutta method is used in COMSYN to integrate the exact equations of motion in a rectangular coordinate system. The magnetic field components of the dipole B{sub x}, B{sub y} and B{sub z} can be obtained from either measurement or directly computed data (MAGNUS, TOSCA). A spline interpolation method is then used to get the field value at the particle position. … more
Date: October 1, 1991
Creator: Huang, Y.
Partner: UNT Libraries Government Documents Department
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Improved tunnel resistance of silvered-polymer mirrors

Description: This report documents the research performed at the Solar Energy Research Institute during fiscal year (FY) 1991 to develop ways to prevent delamination failure (known as tunneling) of silvered-polymer reflector materials. Several promising approaches have been identified and demonstrated that substantially reduce such failures. These approaches include (1) use of Tedlar edge tape rather than the manufacturer-recommended ECP-244 tape, (2) thermal treatment of laminated reflector/substrate const… more
Date: October 1, 1991
Creator: Jorgensen, G.; Schissel, P.; Kennedy, C.; Shinton, Y.; Powell, D. & Siebarth, J.
Partner: UNT Libraries Government Documents Department
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Background information on the SSC project

Description: This report discusses the following information about the Superconducting Super Collider: Goals and milestones; civil construction; ring components; cryogenics; vacuum and cooling water systems; electrical power; instrumentation and control systems; and installation planning.
Date: October 1, 1991
Creator: Warren, J.
Partner: UNT Libraries Government Documents Department
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Monthly energy review, October 1991. [Contains glossary]

Description: This report presents current data on production, consumption, stocks, imports, exports, and prices of the principal energy commodities in the United States. Also included are data on international production of crude oil, consumption of petroleum products, petroleum stocks, and production of electricity from nuclear-powered facilities. 36 figs., 57 tabs.
Date: October 25, 1991
Partner: UNT Libraries Government Documents Department
open access

Inventory of power plants in the United States 1990. [Contains glossary]

Description: The purpose of this publication is to provide year-end statistics about electric generating units operated by electric utilities in the United States (the 50 States and the District of Columbia). The publication also provides a 10-year outlook of future generating unit additions. The Summary Statistics chapter contains aggregate capacity statistics at the national and various regional levels for operable electric generating units and planned electric generating unit additions. Aggregate capacit… more
Date: October 23, 1991
Partner: UNT Libraries Government Documents Department
open access

The new definitive map of White Oak Lake

Description: A map of White Oak Lake was drawn from points on the shoreline established with the use of an electronic distance-measuring theodolite and a hand-held reflecting prism. Average water depths were determined along six transects. A planimeter was used to estimate the area of each section. The volume of each section was determined by multiplying the surface area by the average depth. The total area and volume of White Oak Lake were estimated to be 6.88 ha (17.0 acres) and 43,893 m{sup 3}(1,546,330 … more
Date: October 1, 1991
Creator: Cox, D. K.; Farrow, N. D.; Kyker, W. C.; Faulkner, M. A. & Stubbs, L. M.
Partner: UNT Libraries Government Documents Department
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Preliminary evaluation of hermetic JT/LJT/R P connector socket contact design

Description: This report presents a precursory examination of a number of issues pertaining to socket contacts in hermetic connectors. The principal issues addressed are high-contact resistance and contact chatter (circuit discontinuities). Efforts examining the characteristics of the existing socket contact design, the possibility of connector/contact rework, quick-fix solutions, and contact redesigns are summarized.
Date: October 1, 1991
Creator: Baca, J. R. F.
Partner: UNT Libraries Government Documents Department
open access

A new search for conversion of muonium to antimuonium

Description: To search for conversion of muonium (M {identical to} {mu}{sup +}e{sup {minus}}) to antimuonium ({anti M} {identical to} {mu}{sup {minus}}e{sup +}) with very low background, a new signature was implemented that required the time-coincident detection of the decay e{sup {minus}}({le} 53 MeV) with the atomic e{sup +}({approximately} 13 eV) from decay of an {anti M} atom. A 20 MeV/c {mu}{sup +} beam was stopped in a 9 mg/cm{sup 2} SiO{sub 2} powder target. Muonium, formed in the powder, diffused in… more
Date: October 1, 1991
Creator: Matthias, B.E.
Partner: UNT Libraries Government Documents Department
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CNC electrical discharge machining centers

Description: Computer numerical control (CNC) electrical discharge machining (EDM) centers were investigated to evaluate the application and cost effectiveness of establishing this capability at Allied-Signal Inc., Kansas City Division (KCD). In line with this investigation, metal samples were designed, prepared, and machined on an existing 15-year-old EDM machine and on two current technology CNC EDM machining centers at outside vendors. The results were recorded and evaluated. The study revealed that CNC … more
Date: October 1, 1991
Creator: Jaggars, S.R.
Partner: UNT Libraries Government Documents Department
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Thermodynamics of the hydrodenitrogenation of carbazole

Description: A thermodynamic analysis, based on accurate experimental Gibbs energies of formation, was completed for the key hydrogen-consuming steps in the HDN reaction network for carbazole. The results were compared with literature reaction studies. The concept of crossover temperature'' is shown to be a valuable tool in the interpretation of literature reaction-study results. Methods of nitrogen removal from aromatic materials are discussed in light of the findings of the thermodynamic analysis. It is c… more
Date: October 1, 1991
Creator: Steele, W. V. & Chirico, R. D.
Partner: UNT Libraries Government Documents Department
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Marketing research for EE G Mound Applied Technologies' heat treatment process of high strength materials

Description: This report summarizes research conducted by ITI to evaluate the commercialization potential of EG G Mound Applied Technologies' heat treatment process of high strength materials. The remainder of the report describes the nature of demand for maraging steel, extent of demand, competitors, environmental trends, technology life cycle, industry structure, and conclusion. (JL)
Date: October 9, 1991
Creator: Shackson, R.H.
Partner: UNT Libraries Government Documents Department
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