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Development of an inert ceramic anode to reduce energy consumption in magnesium production. Technical progress report, January 1, 1992--December 31, 1992

Description: Raw material (titania doped with Ta{sub 2}O{sub 5})selection, development of clip casting as greenware forming method, and sintering studies have been completed. External side and shape of the ceramic portion of the anode has been set. Wall thickness is controlled by slip and casting time. Sintered tubes have been made with wall thicknesses 2.5-5.0 mm; optimum thickness will be determined. Modeling studies show that the conceptual design should survive the applied stresses. Results of strength testing of slip cast and sintered titania-Ta{sub 2}O{sub 5} exceed values used in the model. Materials causing bonding of the core`s metal component and the ceramic particulate filler and the ceramic shell need further study. 6 refs, 8 figs, tabs.
Date: December 31, 1992
Partner: UNT Libraries Government Documents Department

Modeling node bandwidth limits and their effects on vector combining algorithms

Description: Each node in a message-passing multicomputer typically has several communication links. However, the maximum aggregate communication speed of a node is often less than the sum of its individual link speeds. Such computers are called node bandwidth limited (NBL). The NBL constraint is important when choosing algorithms because it can change the relative performance of different algorithms that accomplish the same task. This paper introduces a model of communication performance for NBL computers and uses the model to analyze the overall performance of three algorithms for vector combining (global sum) on the Intel Touchstone DELTA computer. Each of the three algorithms is found to be at least 33% faster than the other two for some combinations of machine size and vector length. The NBL constraint is shown to significantly affect the conditions under which each algorithm is fastest.
Date: January 13, 1992
Creator: Littlefield, R. J.
Partner: UNT Libraries Government Documents Department

Tritium production using highly enriched fuel

Description: Preliminary studies utilizing the MOFDA code have been made for tritium production at the K reactors using 33 and 35 grams per foot oralloy (93.5% U-235) in aluminum in conjunction with standard K5N and K5E fuel elements, respectively. For this report, it was assumed that all tritium would be produced in discrete charges of LiAl target elements. It is intended that the study will be extended at some later time to include LiAl splines. The analysis includes the effect of coolant loss on reactivity for hot-or-cold and green-or-exposed conditions for several oralloy loading fractions.
Date: December 18, 1967
Creator: Miller, R. L.
Partner: UNT Libraries Government Documents Department

Interim storage of radioactive xenon and krypton gas

Description: This document contains information on the planning of underwater storage of gas cylinders containing radioactive xenon and krypton gases. The 221-U Canyon Pool Cells 1,2, and 4 appear to be the most promising facilities. The proposed modifications for storing these cylinders underwater include mild steel liners, sealed steel covers, and racks to support the cylinders.
Date: January 14, 1971
Creator: Corlew, R. P.
Partner: UNT Libraries Government Documents Department

Compositions and chemical bonding in ceramics by quantitative electron energy-loss spectrometry

Description: Quantitative electron energy-loss spectrometry was applied to a range of ceramic materials at a spatial resolution of <5 nm. Analysis of Fe L{sub 23} white lines indicated a low-spin state with a charge transfer of {approximately}1.5 electrons/atom onto the Fe atoms implanted into (amorphized) silicon carbide. Gradients of 2 to 5% in the Co:O stoichiometry were measured across 100-nm-thick Co{sub 3}O{sub 4} layers in an oxidized directionally solidified CoO-ZrO{sub 2} eutectic, with the highest O levels near the ZrO{sub 2}. The energy-loss near-edge structures were dramatically different for the two cobalt oxides; those for CO{sub 3}O{sub 4} have been incorrectly ascribed to CoO in the published literature. Kinetically stabilized solid solubility occurred in an AlN-SiC film grown by low-temperature molecular beam epitaxy (MBE) on {alpha}(6H)-SiC, and no detectable interdiffusion occurred in couples of MBE-grown AlN on SiC following annealing at up to 1750C. In diffusion couples of polycrystalline AlN on SiC, interfacial 8H sialon (aluminum oxy-nitride) and pockets of Si{sub 3}N{sub 4}-rich {beta}{prime} sialon in the SiC were detected.
Date: December 31, 1993
Creator: Bentley, J.; Horton, L. L.; McHargue, C. J.; McKernan, S.; Carter, C. B.; Revcolevschi, A. et al.
Partner: UNT Libraries Government Documents Department

Surfactant studies for bench-scale operation. First quarterly technical progress report, July 1, 1992--September 30, 1992

Description: A phase II study has been initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This publication covers the first quarter of work. The major accomplishments were: (1) the refurbishment of the high-pressure, high-temperature reactor autoclave, (2) the completion of four coal liquefaction runs with Pittsburgh {number_sign}8 coal, two each with and without sodium lignosulfonate surfactant, and (3) the development of an analysis scheme for the product liquid filtrate and filter cake. Initial results at low reactor temperatures show that the addition of the surfactant produces an improvement in conversion yields and an increase in lighter boiling point fractions for the filtrate.
Date: December 30, 1992
Creator: Hickey, G. S. & Sharma, P. K.
Partner: UNT Libraries Government Documents Department

Thiophene metabolism by E. coli. Final technical report, September 15, 1987--December 31, 1991

Description: The objective for this project was to continue the genetic analysis of the thiophene oxidation system, in particular: 1. characterization of the biochemical pathway for thiophene oxidation, 2. identification and mapping of any further genes involved in thiophene degradation, 3. analysis of how the thd genes are regulated, and 4. cloning and sequencing of at least some of the thd genes.
Date: December 31, 1991
Creator: Clark, D. P.
Partner: UNT Libraries Government Documents Department

The fluctuation induced Hall effect

Description: The fluctuation induced Hall term, {le}{approximately}{ovr J} {times} {approximately}{ovr B}{ge}, has been measured in the MST reversed field pinch. The term is of interest as a possible source of current self-generation (dynamo). It is found to be non-negligible, but small in that it can account for less than 25% of the dynamo driven current.
Date: February 1, 1993
Creator: Shen, W. & Prager, S. C.
Partner: UNT Libraries Government Documents Department

Follow-up investigations of GPHS motion during heat pulse intervals of reentries from gravity-assist trajectories. Aerospace Nuclear Safety Program

Description: Motion studies of the General Purpose Heat Source Module, GPHS, which were conducted in the heat pulse intervals associated with entries from earth gravity assist trajectories. The APL six-degree-of-freedom reentry program designated TMAGRA6C was used. The objectives of the studies were to (1) determine whether the GPHS module entering the earth`s atmosphere from an earth-gravity-assist trajectory has a preferred orientation during the heat pulse of reentry, (2) determine the effect of magnus force on the roll rate and angle of attack of the GPHS during an EGA entry, (3) determine the effect of the magnitude of pitch and roll damping on the GPHS motion.
Date: March 23, 1992
Creator: Sharbaugh, R. C.
Partner: UNT Libraries Government Documents Department

Energy transfer processes in solar energy conversion. Progress report, March 1, 1991--February 29, 1992

Description: During the past year, we have been working in three general areas: electronic excitation transport in clustered chromophore systems and other complex systems, photo-induced electron transfer and back transfer in liquid solutions in which diffusion and charge interactions are important, and the construction of a new two color dye laser system to enhance our experimental capability.
Date: July 1, 1992
Creator: Fayer, M. D.
Partner: UNT Libraries Government Documents Department

Economic analysis of 10-inch and 12-inch fuel element production for three separate conditions

Description: Three conditions representing various quantities of 10-inch and/or 12-inch fuel elements were presented by the Industrial Engineering Group, IPD, as a basis for initial estimates of economic incentive to partially convert the Production Fuels Section AlSi process to longer fuel elements for FY 1964. An earlier study (Ref. 1) pertained to 10-inch instead of 6-inch enriched fuels. The comparatively larger quantities of the 4 in. longer fuel for full E-N loading showed a larger payout than for the requirements shown in this study. Since the estimates have been prepared without the benefit any process development or equipment design, the validity of the results of this study rest directly with the assumptions. These assumptions are itemized in some detail to explain the basis from which payout was calculated. At best, the study can be used as a preliminary estimate, subject to changes as more detailed analysis are made.
Date: January 28, 1963
Creator: Grubb, F. W.
Partner: UNT Libraries Government Documents Department

Columbia River Pathway Dosimetry Report, 1944-1992. Hanford Environmental Dose Reconstruction Project

Description: The purpose of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation dose that individuals could have received as a result of radionuclide emissions since 1944 from the Hanford Site. One objective of the HEDR Project is to estimate doses to individuals who were exposed to the radionuclides released to the Columbia River (the river pathway). This report documents the last in a series of dose calculations conducted on the Columbia River pathway. The report summarizes the technical approach used to estimate radiation doses to three classes of representative individuals who may have used the Columbia River as a source of drinking water, food, or for recreational or occupational purposes. In addition, the report briefly explains the approaches used to estimate the radioactivity released to the river, the development of the parameters used to model the uptake and movement of radioactive materials in aquatic systems such as the Columbia River, and the method of calculating the Columbia River`s transport of radioactive materials. Potential Columbia River doses have been determined for representative individuals since the initiation of site activities in 1944. For this report, dose calculations were performed using conceptual models and computer codes developed for the purpose of estimating doses. All doses were estimated for representative individuals who share similar characteristics with segments of the general population.
Date: April 1, 1994
Creator: Farris, W. T.; Napier, B. A.; Simpson, J. C.; Snyder, S. F. & Shipler, D. B.
Partner: UNT Libraries Government Documents Department

Database specification for the Worldwide Port System (WPS) Regional Integrated Cargo Database (ICDB)

Description: This Database Specification for the Worldwide Port System (WPS) Regional Integrated Cargo Database (ICDB) describes the database organization and storage allocation, provides the detailed data model of the logical and physical designs, and provides information for the construction of parts of the database such as tables, data elements, and associated dictionaries and diagrams.
Date: March 1, 1994
Creator: Faby, E. Z.; Fluker, J.; Hancock, B. R.; Grubb, J. W.; Russell, D. L.; Loftis, J. P. et al.
Partner: UNT Libraries Government Documents Department

Aromatics oxidation and soot formation in flames. Progress report, August 15, 1990--August 14, 1993

Description: This project is concerned with the kinetics and mechanisms of aromatics oxidation and soot and fullerenes formation in flames. The scope includes detailed measurements of profiles of stable and radical species concentrations in low-pressure one-dimensional premixed flames. Intermediate species identifications and mole fractions, fluxes, and net reaction rates calculated from the measured profiles are used to test postulated reaction mechanisms. Particular objectives are to identify, and to confirm or determine rate constants for, the main benzene oxidation reactions in flames, and to characterize soot and fullerenes and their formation mechanisms and kinetics. Stable and radical species profiles in the aromatics oxidation study are measured using molecular beam sampling with on-line mass spectrometry. The rate of soot formation measured by conventional optical techniques is found to support the hypotheses that particle inception occurs through reactive coagulation of high molecular weight PAH in competition with destruction by OHattack, and that the subsequent growth of the soot mass occurs through addition reactions of PAH and C{sub 2}H{sub 2} with the soot particles. During the first year of this reporting period, fullerenes C{sub 60} and C{sub 70} in substantial quantities were found in the flames being studied. The fullerenes were recovered, purified and spectroscopically identified. The yields of C{sub 60} and C{sub 70} were then determined over ranges of conditions in low-pressure premixed flames of benzene and oxygen.
Date: April 1, 1993
Creator: Howard, J. B.; Pope, C. J.; Shandross, R. A. & Yadav, T.
Partner: UNT Libraries Government Documents Department

Recent progress in irrational conformal field theory

Description: In this talk, I will review the foundations of irrational conformal field theory (ICFT), which includes rational conformal field theory as a small subspace. Highlights of the review include the Virasoro master equation, the Ward identities for the correlators of ICFT and solutions of the Ward identities. In particular, I will discuss the solutions for the correlators of the g/h coset construction and the correlators of the affine-Sugawara nests on g {contains} h{sub 1} {contains} {hor_ellipsis} {contains} h{sub n}. Finally, I will discuss the recent global solution for the correlators of all the ICFT`s in the master equation.
Date: September 1, 1993
Creator: Halpern, M. B.
Partner: UNT Libraries Government Documents Department

Format and Content Guide for Title 40 CFR 191 and Title 40 CFR 268.6 Compliance Reports

Description: This Format and Content Guide was followed in preparing the WIPP Compliance Status Report submitted in March 1994 and will be used for the compliance documents scheduled for submittal in the Spring of 1995. The Compliance Status Report was issued to stakeholders in March 1994 and describes the status of associated activities on compliance with the requirements in Title 40 CFR 268.6 and Title 40 CFR 191. The Compliance Status Report focuses on (1) the information required for a demonstration of compliance, (2) preliminary results, (3) the areas of the WIPP program that are either not currently mature enough, or do not provide adequate margin for a demonstration of compliance, and (4) the areas of the WIPP program that will be focused upon to provide the remaining necessary information for use in the 1995 compliance demonstration reports. The Compliance Status Report is not intended to constitute a statement of compliance or a demonstration of compliance. It is intended to report the status of progress made to date in project efforts to achieve the required level of data/information necessary for the required compliance demonstrations. Comments on the Compliance Status Report from stakeholders will likely result in a modified Format and Content Guide, as will the promulgation of the EPA`s Compliance Criteria for WIPP (40 CFR 194).
Date: May 1, 1994
Partner: UNT Libraries Government Documents Department

Low Z impurity ion extraction from TFTR ion sources

Description: TFTR deuterium neutral beams have been operated unintentionally with significant quantities of extracted water ions. Water has been observed with an Optical Multichannel Analyzer (OMA) during beam extraction when small water leaks were present within the arc chamber. These leaks were thermally induced with the contamination level increasing linearly with pulse length. 6% of the beam current was attributed to water ions for the worst leak, corresponding to an instantaneous value of 12% at the end of a 1.5 s pulse. A pre-calorimeter collimator was damaged as a result of this operation. A similar contamination is observed during initial operation of ion sources exposed to air. This latter contamination is attributed to the synthesis, from adsorbed air, of either D{sub 2}O or the indistinguishable ND{sub 3}. Initial operation of new ion sources typically produces a contamination level of {approximately}2%. These impurities are reduced to undetectable levels after 50 to 100 beam pulses. Once a water molecule is present in the plasma generator, it is predominantly ionized rather than dissociated, resulting in the extraction of only trace amounts of hydrogenated ions. The addition of water to the extracted beam also reduces the optimum perveance, moving the typical underdense operating point closer to optimum, causing the frequency of grid faults to increase. Close to 90% of the water extracted from ion sources with water leaks was deuterated, implying that the potential exists for the production of tritiated water during TFTR`s forthcoming DT operation. Isotope exchange in the plasma generator takes place rapidly and is believed to be surface catalyzed. The primary concern is with O implanted into beam absorbers recombining with tritium, and the subsequent hold up of T{sub 2}O on cryopanels. Continuous surveillance with the OMA diagnostic during DT operation will ensure that ion sources with detectable water are not operated ...
Date: April 1, 1993
Creator: Kamperschroer, J. H.; Grisham, L. R.; Newman, R. A.; O`Connor, T. E.; Stevenson, T. N.; von Halle, A. et al.
Partner: UNT Libraries Government Documents Department

A model for forming airborne synthetic aperture radar images of underground targets

Description: Synthetic Aperture Radar (SAR) from an airborne platform has been proposed for imaging targets beneath the earth`s surface. The propagation of the radar`s energy within the ground, however, is much different than in the earth`s atmosphere. The result is signal refraction, echo delay, propagation losses, dispersion, and volumetric scattering. These all combine to make SAR image formation from an airborne platform much more challenging than a surface imaging counterpart. This report treats the ground as a lossy dispersive half-space, and presents a model for the radar echo based on measurable parameters. The model is then used to explore various imaging schemes, and image properties. Dynamic range is discussed, as is the impact of loss on dynamic range. Modified window functions are proposed to mitigate effects of sidelobes of shallow targets overwhelming deeper targets.
Date: January 1, 1994
Creator: Doerry, A. W.
Partner: UNT Libraries Government Documents Department

Secondary oil recovery from selected Carter sandstone oilfields -- Black Warrior Basin, Alabama. Quarterly technical progress report, September 1--November 30, 1993

Description: Anderman/Smith Operating Co. is operating a secondary oil recovery project involving the Carter sandstone in northwest Alabama. The project objectives are: (1) to increase the ultimate economic recovery of oil from the Carter reservoirs, thereby increasing domestic reserves and lessening US dependence on foreign oil; (2) to extensively model, test, and monitor the reservoirs so their management is optimized; and (3) to assimilate and transfer the information and results gathered to other US oil companies to encourage them to attempt similar projects. As a result of waterflood operations at the Central Buff unit, oil production from the Fowler Brasher 7--9 well increased to 40--50 stb/d in late October, and averaged about 45 stb/d in November with no measurable water production. Production at the Fowler Dodson 8--12 was more erratic during the same period. In October, the oil rate for this well increased to nearly 17 stb/d with no reported water production. However, in November the oil production rate declined to about 9 stb/d with an associated average water rate of nearly 17 bpd. Water analysis showed that this produced water was significantly fresher than the connate water produced prior to waterflood operations. This provides evidence for early breakthrough of water injected at the Jones 7--16 well and will be an important consideration in the reservoir modeling study being performed for the unit. There has been essentially no change in the waterflood response at the North Fairview Unit during the last quarter. Oil production rates from the three producing wells have remained unchanged; that is, 3 stb/d for Smith 33-6, 2 stb/d for Perkins 33--11, and 1 stb/d for the Perkins Young 33--10 well.
Date: January 15, 1994
Creator: Anderson, J. C.
Partner: UNT Libraries Government Documents Department

The Second Colloquium on Petroleum Engineering Education

Description: This paper describes findings from the Second Colloquium on Petroleum engineering Education. The purpose of this colloquium was to provide a forum for petroleum engineering educators and representatives from industry and government to explore critical issues facing petroleum engineering education as we move into the 21st Century. It was expected that the colloquium would identify areas where changes are needed in petroleum engineering education, to best prepare students for careers in the oil and gas industry or other, related industries.
Date: November 30, 1993
Creator: Willhite, G. P. & Forney, R. H.
Partner: UNT Libraries Government Documents Department

FORTRAN M as a language for building earth system models

Description: FORTRAN M is a small set of extensions to FORTRAN 77 that supports a modular or object-oriented approach to the development of parallel programs. In this paper, I discuss the use of FORTRAN M as a tool for building earth system models on massively parallel computers. I hypothesize that the use of FORTRAN M has software engineering advantages and outline experiments that we are conducting to investigate this hypothesis.
Date: December 31, 1992
Creator: Foster, I.
Partner: UNT Libraries Government Documents Department

Geochemistry of FBC waste-coal slurry solid mixtures. Final technical report, September 1, 1992--August 31, 1993

Description: The three tasks conducted in this research project were related to understanding the geochemistry and mineralogy of the co-disposal of fluidized bed combustion (FBC) wastes with coal slurry solid (CSS) from a coal preparation plant. During coal cleaning, pyrite, other heavy minerals and rock fragments are separated from the coal and discharged in an aqueous slurry to an impoundment. After dewatering and closure of the impoundment, the pyrite can oxidize and produce acid that can migrate into the underlying groundwater system. The addition of FBC residue to the CSS will buffer the pore water pH to approximately 7.8. In Task 1, soluble components and acid-base react ion products from mixtures of FBC waste and CSS were extracted for 3 to 180 days in aqueous batch experiments. The results of these extractions showed that, eventually, the extracts would attain a pH between 7 and 8. That pH range is characteristic of an aqueous system in equilibrium with calcite, gypsum, and atmospheric carbon dioxide. After 180 days, the mean calcium concentration in all of the extracts was 566{+-}18 mg/L and sulfate concentrations averaged 2420{+-}70 mg/L. In Task 2, three extracts from CSS/FBC residue mixtures were prepared for use in experiments to determine the adsorption/desorption reactions that occur between solutes in the extracts and two common Illinois soils. Time constraints allowed the use of only two of the extracts for adsorption studies. The concentrations of most solutes were not significantly lowered by adsorption at the pH of the extract-soil suspension, nor over a wide range of pH. The results suggest that the type of solutes that were released by the CSS/FBC residue mixture would not be attenuated by adsorption. In a modified Task 3, the literature on the kinetics of pyrite oxidation in near-neutral to alkaline pH was reviewed in preparation for future ...
Date: December 31, 1993
Creator: Dreher, G. B.; Roy, W. R.; Steele, J. D. & Heidari, M.
Partner: UNT Libraries Government Documents Department