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Control of triacylglycerol biosynthesis in plants

Description: Seeds of most species of the Umbelliferae (Apiaciae), Araliaceae, and Garryaceae families are characterized by their high content of the unusual C[sub 18] monounsaturated fatty acid petroselinic acid (18:l[Delta][sup 6cis]). Prior to a recent report of this lab, little was known of the biosynthetic origin of the cis[Delta][sup 6] double bond of petroselinic acid. Such knowledge may be of both biochemical and biotechnological significance. Because petroselinic acid is potentially the product of … more
Date: January 31, 1993
Partner: UNT Libraries Government Documents Department
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Revitalizing a mature oil play: Strategies for finding and producing unrecovered oil in Frio Fluvial-Deltaic reservoirs of South Texas

Description: During this second project quarter, screening of South Texas fields within the Frio Fluvial-Deltaic Sandstone/Vicksburg Fault Zone oil play was completed. Fields were to identify reservoirs that have a large remaining oil resource, are in danger of premature abandonment, and have geological and production data in sufficient quantity and of suitable quality to facilitate advanced reservoir characterization studies (subtask 1). Two fields have been selected for inclusion in this study: Tijerina-C… more
Date: March 31, 1993
Creator: Tyler, N.
Partner: UNT Libraries Government Documents Department
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Study of Intermediates From Transition Metal Excited-State Electron- Transfer Reactions

Description: Progress on 6 projects is reported: excited state absorption spectrum of Ru(bpy)[sub 3][sup 2+], solvent cage model for electron transfer quenching, reductive quenching of [sup *]Cr(III) complexes, solution medium effects in oxidative quenching of [sup *]Ru(II) complexes, photosensitized oxidation of phenol in aqueous solution, and quenching of Ru(II) complexes by oxygen.
Date: March 31, 1993
Creator: Hoffman, M. Z.
Partner: UNT Libraries Government Documents Department
open access

Development and use of an apparatus to measure the dynamic surface properties of coal-water slurry fuels for applications to atomization characteristics

Description: The Texas A M University (TAMU) has been awarded a DOE contract to study dynamic properties and atomization characteristics of coal-water slurry (CWS) fuels. Additives are essential for better mixing and stable suspension of coal powders and these additives change CWS properties. Dynamic properties will have major effects on CWS fuel atomization, which constitutes highly dynamic processes, and will determine the combustion as well as the pollutant formation behaviors. The dynamic surface tensio… more
Date: January 31, 1993
Creator: Kihm, K.D.
Partner: UNT Libraries Government Documents Department
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Application of magnetomechanical hysteresis modeling of magnetic techniques for monitoring neutron embrittlement and biaxial stress

Description: Research was done on the biaxial stress problem accomplished in the first half of the second year. All of the work done was preparatory to magnetic measurements. Issues addressed were: construction of a model for extracting changes in the magnetic properties of a specimen from the readings of an indirect sensor; initial development of a model for how biaxial stress alters the intrinsic magnetic properties of thespecimen; use of finite element stress analysis modeling to determine a detailed sha… more
Date: January 31, 1993
Creator: Sablik, M.J.; Kwun, H. & Burkhardt, G.L.
Partner: UNT Libraries Government Documents Department
open access

SET Careers Program: An interactive science, engineering, and technology career education exhibit. [A brief summary report]

Description: The New York Hall of Science, in response to the national crisis in education and employment in science and engineering, is developing and pilot testing a unique, interactive, video-based, hypermedia series on energy-related and other science and engineering careers for middle and junior high school students. Working in collaboration with the Consortium for Mathematics and its Applications (COMAP) and the Educational Film Center (EFC), this pilot-demonstration phase will last 14 months, during … more
Date: March 31, 1993
Creator: Cole, P.R.
Partner: UNT Libraries Government Documents Department
open access

Performance of CVR coatings for PBR fuels

Description: As part of the component development process for the particle bed reactor (PBR), it is necessary to develop coatings for fuel particles which will be time and temperature stable. These coatings must not only protect the particle from attack by the hydrogen coolant, but must also help to maintain the bed in a coolable geometry and mitigate against fission product release. In order to develop these advanced coatings, a process to produce chemical vapor reaction (CVR) coatings on fuel for PBRs has… more
Date: December 31, 1993
Creator: Adams, J. W.; Barletta, R. E.; Svandrlik, J. & Vanier, P. E.
Partner: UNT Libraries Government Documents Department
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Studies in physico-chemical hydrodynamics of extended systems. Annual progress report, November 1, 1993--October 31, 1994

Description: The object of the proposed research program is a unified theoretical approach to the description of a variety of physico-chemical hydrodynamic systems characterized by a significant disparity between the spatial scales involved. By appropriately performed averaging over short scales, one may considerably simplify the original problem, sometimes even lowering its effective dimensionality, and thereby making the latter quite tractable either analytically or numerically. Specifically, the author p… more
Date: December 31, 1993
Creator: Sivashinsky, G. I.
Partner: UNT Libraries Government Documents Department
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Stability and precipitation kinetics in Si{sub 1{minus}y}C{sub y}/Si and Si{sub 1{minus}x{minus}y}Ge{sub x}C{sub y}/Si heterostructures prepared by solid phase epitaxy

Description: This study investigates the stability of metastable Si{sub 1{minus}y}C{sub y}/Si heterostructures during rapid thermal annealing (RTA) over a temperature range of 1,000--1,150 C. Heterostructures of Si{sub 1{minus}y}C{sub y}/Si and Si{sub 1{minus}x{minus}y}Ge{sub x}C{sub y}/Si (x {equals} 0.77, Y {<=} .0014) were formed by solid phase epitaxy from C implanted, preamorphized substrates using a 30 minute 700 C anneal in N{sub 2}. The occupancy of C in substitution lattice sites was monitored by F… more
Date: December 31, 1993
Creator: Strane, J. W.; Picraux, S. T.; Stein, H. J.; Lee, S. R.; Candelaria, J.; Theodore, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Demonstration testing and evaluation of in situ soil heating: Management Plan

Description: This document is the Management Plan for US DOE contract entitled, {open_quotes}Demonstration, Testing and Evaluation of In Situ Soil Heating,{close_quotes} Contract No. DE-AC05-93OR22160, IITRI Project No. C06787. In this project IITRI will demonstrate an in situ soil heating technology for the removal of hazardous organic contaminants present in the soil. In situ heating will be accomplished by the application of 60 Hz ac power to the soil. The soil will be heated to a temperature of about 90… more
Date: December 31, 1993
Creator: Dev, H.
Partner: UNT Libraries Government Documents Department
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New high temperature plasmas and sample introduction systems for analytical atomic emission and mass spectrometry. Progress report: January 1, 1993--December 31, 1993

Description: In this research, new high-temperature plasmas and new sample introduction systems are explored for rapid elemental and isotopic analysis of gases, solutions, and solids using mass spectrometry and atomic emission spectrometry. During the period January 1993--December 1993, emphasis was placed on (a) analytical investigations of atmospheric-pressure helium inductively coupled plasma (He ICP) that are suitable for atomization, excitation, and ionization of elements possessing high excitation and… more
Date: December 31, 1993
Creator: Montaser, A.
Partner: UNT Libraries Government Documents Department
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Research activities of Martin C. Casdagli at SFI September 1989--May 1991

Description: My research over this period has focused on the theory and application of non-linear time series forecasting. The purpose of time series forecasting is to predict apparently random behavior about which we have little or no knowledge. A time series is a set of values that change in time, for example, daily stock market prices for a given set of firms, or the volume of the polar ice caps over the last two million years. Recent developments in the understanding of chaotic dynamical systems have st… more
Date: December 31, 1993
Partner: UNT Libraries Government Documents Department
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On the nature of striae in strontium barium niobate

Description: Strontium barium niobate crystals were grown by the Czochralski technique. These crystals were 15--20 mm in diameter and 25 to 75 mm long. Two types stride, designated as coarse and fine, were characterized. The coarse stride are optically dense and are spaced by 100 to 500 {mu}m apart; the fine striae are optically less dense and spaced 5--50 {mu}m apart. The origins of the stride are attributed to thermal fluctuations in the melt related to the control system and to rotation of the growing cr… more
Date: December 31, 1993
Creator: Monchamp, R. R.; Mihalik, G. B. & Franks, L. A.
Partner: UNT Libraries Government Documents Department
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Sonic Enhanced Ash Agglomeration and Sulfur Capture. Technical progress report, July 1993--September 1993

Description: A major concern with the utilization of coal in directly fired gas turbines is the control of particulate emissions and reduction of sulfur dioxide, and alkali vapor from combustion of coal, upstream of the gas turbine. Much research and development has been sponsored on methods for particulate emissions control and the direct injection of calcium-based sorbents to reduce SO{sub 2} emission levels. The results of this research and development indicate that both acoustic agglomeration of particu… more
Date: December 31, 1993
Partner: UNT Libraries Government Documents Department
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Nuclear reaction analysis of hydrogen in SSC beam pipe materials

Description: To control the photodesorption of molecular hydrogen, it is advantageous to reduce the amount of hydrogen in candidate SSC beam pipe materials and identify those procedures that: (1) lead to contamination of the beam pipe surface or materials, (2) would reduce the amount of hydrogen on the surface or in the bulk and (3) could be used for in-situ cleaning during Collider assembly or during Collider maintenance. Nuclear Reaction Analysis (NRA) can be used to quantitatively measure the amount of h… more
Date: December 31, 1993
Creator: Ruckman, M. W.; Strongin, M. & Lanford, W. A.
Partner: UNT Libraries Government Documents Department
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Na/Ca catalyzation of Illinois coals for gasification. Final technical report, September 1, 1992--August 31, 1993

Description: Gasification for power generation via IGCC processes is expected to become an important market for high sulfur Illinois Basin coals. Fluid-bed gasifiers have significant advantages over entrained flow processes. These advantages include ease of control, large turndown capacity, high thermal efficiency, and moderate oxygen and steam requirements. Three of the most pressing technical problems in fluid-bed gasification of Illinois coals are the caking tendency, high sulfur content, and low carbon … more
Date: December 31, 1993
Creator: Jha, M. C. & McCormick, R. L.
Partner: UNT Libraries Government Documents Department
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Power systems development facility. Quarterly technical progress report, July 1--September 30, 1993

Description: This quarterly technical progress report summarizes work completed during the Second Quarter of the Second Budget Period, July 1 through September 30, 1993, under the Department of Energy (DOE) Cooperative Agreement No. DE-FC21-90MC25140 entitled ``Hot Gas Cleanup Test Facility for Gasification and Pressurized Combustion.`` The objective of this project is to evaluate hot gas particle control technologies using coal-derived gas streams. This will entail the design, construction, installation, a… more
Date: December 31, 1993
Partner: UNT Libraries Government Documents Department
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[Experiment studies of electron-positron interactions at the Stanford Linear Accelerator Center]. Progress report, calendar year 1993

Description: The High Energy Physics group at the University of Massachusetts has continued its` program of experimental studies of electron-positron interactions at the Stanford Linear Accelerator Center (SLAC). The group activities have included: analysis of data taken between 1982 and 1990 with the TPC detector at the PEP facility, continuing data collection and data analysis using the SLC/SLD facility, planning for the newly approved B-factory at SLAC, and participation in design studies for future high… more
Date: December 31, 1993
Creator: Hertzbach, S. S. & Kofler, R. R.
Partner: UNT Libraries Government Documents Department
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[Toxicity studies of mild gasification products: Quarterly technical progress report, April--June 1993]

Description: The major hypothesis of carcinogenesis is that malignancy is due to an alteration (mutation) of the genetic material in a somatic cell. Reactive electrophilic metabolites are generated from many chemicals by the action of endogenous mixed function oxidases. These reactive metabolites may bind to cellular macromolecules, such as DNA, and can, therefore, initiate a mutagenic or carcinogenic event. Prokaryotes and non-mammalian eukaryotes are used in mutation assays, while cultured mammalian cells… more
Date: December 31, 1993
Partner: UNT Libraries Government Documents Department
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Two-phase power-law modeling of pipe flows displaying shear-thinning phenomena

Description: This paper describes work in modeling concentrated liquid-solids flows in pipes. COMMIX-M, a three-dimensional transient and steady-state computer program developed at Argonne National Laboratory, was used to compute velocities and concentrations. Based on the authors` previous analyses, some concentrated liquid-solids suspension flows display shear-thinning rather than Newtonian phenomena. Therefore, they developed a two-phase non-Newtonian power-law model that includes the effect of solids co… more
Date: December 31, 1993
Creator: Ding, Jianmin; Lyczkowski, R. W. & Sha, W. T.
Partner: UNT Libraries Government Documents Department
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Transient studies of low temperature catalysts for methane conversion. Quarterly technical progress report, June 30, 1993--September 30, 1993

Description: This report summarizes studies on the oxidative coupling of methane on metallo oxide catalysts. A previous report summarized the results on the partial oxidation of methane on Li promoted VPO{sub 4} catalysts and the role of the Li promotion on increasing formaldehyde selectivity. The results of such study have been summarized in a paper submitted for publication. Given the relatively low conversion of methane and the low formaldehyde selectivity, it was decided to continue studying the oxidati… more
Date: December 31, 1993
Creator: Wolf, E. E.
Partner: UNT Libraries Government Documents Department
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Structural analysis of amorphous phosphates using high performance liquid chromatography

Description: Determining the atomic-scale structure of amorphous solids has proven to be a formidable scientific and technological problem for the past 100 years. The technique of high-performance liquid chromatography (HPLC) provides unique detailed information regarding the structure of partially disordered or amorphous phosphate solids. Applications of the experimental technique of HPLC to phosphate solids are reviewed, and examples of the type of information that can be obtained with HPLC are presented.… more
Date: December 31, 1993
Creator: Sales, B. C.; Boatner, L. A.; Chakoumakos, B. C.; McCallum, J. C.; Ramey, J. O. & Zuhr, R. A.
Partner: UNT Libraries Government Documents Department
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A 200 kV fast rise time, low jitter, trigger system with magnetic pulse sharpener

Description: The DARHT Facility is being designed at Los Alamos National Laboratory to produce high resolution flash radiographs of hydrodynamic experiments. Two linear induction accelerators (LIA), each in the range of 16 to 20 MeV, will be used to produce intense bremsstrahlung X-ray pulses of short duration (60 ns flat top). Each LIA will produce a 3 kA, high brightness, electron beam using a 4 MeV injector and a series of 250 kV induction cells. Technology demonstration of key accelerator subsystems is … more
Date: December 31, 1993
Creator: Jaitly, N. C.; Ramrus, A.; Coleman, M. D.; Earley, L. M.; Downing, J. N.; Reisch, H. H. et al.
Partner: UNT Libraries Government Documents Department
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