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Data Summary of Municipal Solid Waste Management Alternatives
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A unified theory of resonant excitation of kinetic ballooning modes by energetic ions/alpha particles in tokamaks
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 those resonant ions with the highest energy. Implications of the theory for present and future generation fusion experiments are discussed. 16 refs.
Date:
October 1, 1991
Creator:
Biglari, H. & Chen, L.
System:
The UNT Digital Library
(Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)
This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.
Date:
October 1, 1991
Creator:
unknown
System:
The UNT Digital Library
Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties
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(diphenylsilyldiacetylene) via dehydrogenation, was reinvestigated. Spectroscopic studies showed that the polymer had a structure of polyacetylene type not diacetylene. Diphenyldiethynylgermane and a series of diorganodiethynylsilances were synthesized. These could be polymerized in the presence of MoCl{sub 5} or WCl{sub 6} to afford a soluble, violet material with Mw as high as 108,000. 100 refs., 56 figs., 16 tabs.
Date:
October 7, 1991
Creator:
Pang, Yi.
System:
The UNT Digital Library
The interpretation of reflectometry measurements of plasma fluctuations
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 numerical solutions of the one dimensional full wave equation for the propagation near cutoff frequencies has been used to show how to interpret reflectometry measurements. For density perturbations with wavelengths near the density scale length, the external fluctuating phase can be simply interpreted in terms of a fluctuating density near the cutoff layer. However, the amplitude of the phase response falls substantially as the fluctuation wavelength, {Lambda}, approaches the free space wavelength of the reflected wave, {lambda}{sub o}, and the location of the maximum response moves out in front of the cutoff layer following the wave matching condition k{sub {Lambda}} = 2k {approx} 2{eta}(x)k{sub 0}. Similarly, correlation measurements of density fluctuations from probe waves of different wavelengths are shown to be limited to about four …
Date:
October 1, 1991
Creator:
Bretz, N.
System:
The UNT Digital Library
Thermodynamic model for calorimetric and phase coexistence properties of coal derived fluids
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 distribution of heteroatoms. A computational thermodynamic model for VLE, excess enthalpies and heat capacities of coal derived liquids has been developed. The model uses the modified UNIFAC correlation for the liquid phase. Some unavailable UNIFAC interactions parameters have been regressed from experimental VLE and excess enthalpy data. The computations are carried out using the method of continuous thermodynamics. Mode is used to derive interesting conclusions on the effect of oxygen, nitrogen, and sulfur heteroatoms on the thermodynamic properties of coal liquids. When compared with limited experimental data available for coal liquids the model shows good agreement. Some progress has been made on binary VLE measurements and size exclusion chromatography of coal liquids.
Date:
October 1, 1991
Creator:
Kabadi, V. N.
System:
The UNT Digital Library
Research in theoretical nuclear physics
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.
System:
The UNT Digital Library
Investigations of CuInSe sub 2 Thin Films and Contacts
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, a second part of the program investigated how the morphologies, phases, and reactions of pre-selenization Cu-In structures are affected by the deposition process and heat treatments. 7 refs., 6 figs.
Date:
October 1, 1991
Creator:
Nicolet, M. A.
System:
The UNT Digital Library
Cationically polymerizable monomers derived from renewable sources
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. Their photopolymerization was carried out using cationic photoinitiators and the mechanical properties of the resulting polymers characterized. Preliminary biodegradation studies are being conducted on the photopolymerized films from several of these oils. Limonene was cationically polymerized to give dimers and the dimers epoxidized to yield highly reactive monomers suitable for coatings, inks and adhesives. The direct phase transfer epoxidation of squalene and natural rubber was carried out. The modified rubbers undergo facile photocrosslinking in the presence of onium salts to give crosslinked elastomers. 12 refs., 3 figs., 10 tabs.
Date:
October 1, 1991
Creator:
Crivello, J. V.
System:
The UNT Digital Library
Theoretical study of the structure, energetics, and dynamics of silicon and carbon systems using tight-binding approaches
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 physical origin of the negative thermal expansion observed in silicon is explained. A tight-binding total energy model is generated capable of describing carbon systems with a variety of atomic coordinations and topologies. The model reproduces the total energy versus volume curves of various carbon polytypes as well as phonons and elastic constants of diamond and graphite. The model has also been used in the molecular-dynamics simulation of the properties of carbon clusters. The calculated ground-state geometries of small clusters (C{sub 2}--C{sub 10}) correlates well with results from accurate quantum chemical calculations, and the structural trend of clusters from C{sub 2} to C{sub 60} are investigated. 67 refs., 19 figs.
Date:
October 25, 1991
Creator:
Xu, Chunhui.
System:
The UNT Digital Library
FY 1992 task plans for the Hanford Environmental Dose Reconstruction Project
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 limited radionuclides, in a limited geographical area and time period. Phase 1 ended in FY 1990. In February 1991, the TSP decided to shift the project planning approach away from phases--which were centered around completion of major portions of technical activities--to individual fiscal years (FYs), which span October of one year through September of the next. Therefore, activities that were previously designated to occur in phases are now designated in an integrated schedule to occur in one or more of the next fiscal years into FY 1995. Task plans are updated every 6 months. In FY 1992, scientists will continue to improve Phase 1 data and models to calculate more accurate and precise dose estimates. The plan for FY 1992 has been prepared based …
Date:
October 1, 1991
Creator:
unknown
System:
The UNT Digital Library
Ion-optical studies for improved ion transmission in multistage isotope-ratio mass spectrometers
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 the focus of each stage. For existing mass spectrometers with tandem magnets of normal geometry, our studies determined a feasible design change that significantly increases ion transmission through the analyzer. The use of a cylindrical einzel lens or an electrostatic quadrupole lens near the focal point between the magnets provides vertical focusing of the ion beam to achieve the improved transmission. We also established a new mass spectrometer design that give 100% transmission through tandem magnetic analyzers and through a third-stage electrostatic analyzer without the use of an intermediate focusing lens. Non-normal magnetic field boundaries provide ion beam focusing in the vertical plant to achieve this complete transmission. 19 refs., 27 figs., 3 tabs.
Date:
October 1, 1991
Creator:
Stoffels, J.J. (Pacific Northwest Lab., Richland, WA (United States)) & Laue, H.J. (Purdue Univ., Lafayette, IN (United States))
System:
The UNT Digital Library
Electric power monthly, October 1991. [CONTAINS GLOSSARY]
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 level are published in the EPM on capability of new plants, net generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fuel. 4 figs., 63 tabs.
Date:
October 11, 1991
Creator:
unknown
System:
The UNT Digital Library
Petroleum marketing monthly, October 1991. [Contains glossary]
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 gasoline, distillates, residuals, aviation fuels, kerosene, and propane are presented. 12 figs., 55 tabs.
Date:
October 10, 1991
Creator:
unknown
System:
The UNT Digital Library
Manual for COMSYN: A orbit integration code for the study of beam dynamics in compact synchrotrons
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. For standard quadrupole and sextupole, the analytical expression is employed to compute its field distribution.
Date:
October 1, 1991
Creator:
Huang, Y.
System:
The UNT Digital Library
Improved tunnel resistance of silvered-polymer mirrors
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 constructions, and (3) application of silver to the polymer film through an alternative deposition process. Approaches 1 and 2 offer readily available engineering solutions to the delamination problem. Approaches 2 and 3 provide tunnel resistance over the entire surface of the reflector material, including the edges. Tedlar (a polyvinyl fluoride from DuPont) tape is an opaque white tape available in different widths from 3M Company. The base material has demonstrated outstanding outdoor durability. Thermal treatment of ECP-305 laminated to substrate materials has demonstrated outstanding resistance to tunneling. Alternative silver deposition techniques such as sputtering (rather than thermal evaporation) offer increased resistance to tunneling. 15 refs., 10 figs.
Date:
October 1, 1991
Creator:
Jorgensen, G.; Schissel, P.; Kennedy, C.; Shinton, Y.; Powell, D. & Siebarth, J.
System:
The UNT Digital Library
Background information on the SSC project
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.
System:
The UNT Digital Library
Monthly energy review, October 1991. [Contains glossary]
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
Creator:
unknown
System:
The UNT Digital Library
Inventory of power plants in the United States 1990. [Contains glossary]
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 capacity data at the national level are presented by energy source and by prime mover. Aggregate capacity data at the various regional levels are presented by prime energy source. Planned capacity additions in new units are summarized by year, 1991 through 2000. Additionally, this chapter contains a summary of electric generating unit retirements, by energy source and year, from 1991 through 2000. The chapter on Operable Electric Generating Units contains data about each operable electric generating unit and each electric generating unit that was retired from service during the year. Additionally, it contains a summary by energy source of electric generating unit capacity additions and retirements during 1990. Finally, the chapter on Projected Electric Generating Unit Additions contains data about each electric generating unit scheduled by electric utilities to start operation …
Date:
October 23, 1991
Creator:
unknown
System:
The UNT Digital Library
The new definitive map of White Oak Lake
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 ft{sup 3}), respectively. The lake's surface area has been reduced at an average rate of 0.7% per year, and its volume has been reduced at an average rate of 1.1% per year. The volume of the lake can be reliably estimated only from current depth measurements throughout the lake, not from stage heights at the dam. The lake should be remapped periodically, and an estimate of the sediment volume should be made. 6 refs., 3 figs., 1 tab.
Date:
October 1, 1991
Creator:
Cox, D. K.; Farrow, N. D.; Kyker, W. C.; Faulkner, M. A. & Stubbs, L. M.
System:
The UNT Digital Library
Preliminary evaluation of hermetic JT/LJT/R P connector socket contact design
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.
System:
The UNT Digital Library
A new search for conversion of muonium to antimuonium
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 into a vacuum region at thermal velocities and was observed for a coincidence of {anti M} decay products. Any decay e{sup {minus}} was charge and momentum analyzed in a dipole magnet and tracked by an array of MWPCs; any atomic e{sup +} was electrostatically collected, accelerated to 5.7 keV, and magnetically transported to a microchannel plate detector. To calibrate the signature, M was observed for the first time by coincidence of its decay e{sup +} and its atomic e{sup {minus}}. A maximum likelihood analysis of the position distribution of decay origins finds no {anti M} events and less than 2 at 90% confidence. This places an upper limit on the conversion probability per atom of S{anti M} < 6.5 {times} 10{sup …
Date:
October 1, 1991
Creator:
Matthias, B.E.
System:
The UNT Digital Library
CNC electrical discharge machining centers
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 EDM centers are a capability that should be established at KCD. From the information gained, a machine specification was written and a shop was purchased and installed in the Engineering Shop. The older machine was exchanged for a new model. Additional machines were installed in the Tool Design and Fabrication and Precision Microfinishing departments. The Engineering Shop machine will be principally used for the following purposes: producing deep cavities in small corner radii, machining simulated casting models, machining difficult-to-machine materials, and polishing difficult-to-hand polish mold cavities. 2 refs., 18 figs., 3 tabs.
Date:
October 1, 1991
Creator:
Jaggars, S.R.
System:
The UNT Digital Library
Thermodynamics of the hydrodenitrogenation of carbazole
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 concluded that the removal of nitrogen from heterocyclic aromatic nitrogen-containing compounds with conventional hydrodesulfurization catalysts, temperatures, and hydrogen pressures occurs under thermodynamic control'' with unavoidably high hydrogen consumption. The report also concludes that to reduce hydrogen consumption in the HDN of carbazole, pathways via 1,2,3,4a,9a-hexahydrocarbazole must be followed. Conditions under which these processes are possible are discussed. 36 refs., 9 figs.
Date:
October 1, 1991
Creator:
Steele, W. V. & Chirico, R. D.
System:
The UNT Digital Library
Marketing research for EE G Mound Applied Technologies' heat treatment process of high strength materials
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.
System:
The UNT Digital Library