Search Results

Lower-hybrid current drive with opposing ohmic drive on PLT

Description: Two distinct conditions where the rf phase velocity is directed opposite to the ohmically induced electron drift have been studied experimentally: (1) rf current ramp-up (f/sub p/ > 0), where an induced electric field opposes the current increase; (2) rf current ramp-down, where waves are launched opposite the electron drift direction for a decaying plasma current. The time behavior of the electron tail is inferred from hard x-ray (30 to 750 keV) emission as a function of angle to B. In cases (1) and (2) we find that the emission amplitude in the reverse (opposite the LH phase velocity) direction increases throughout the rf pulse, while it is constant in the forward direction. This increase indicates that some high energy electrons are accelerated or are even running away in the direction opposite to the main rf produced tail. It also indicates for case (1) that the electric field in the plasma center has been reversed by the rf current drive.
Date: June 1, 1983
Creator: Stevens, J.; Von Goeler, S.; Bernabei, S.; Chu, T.K.; Hooke, W.; Jobes, F. et al.
Partner: UNT Libraries Government Documents Department

Structure analysis of OmpC, one of the major proteins in the outer membrane of E. coli, by high resolution electron microscopy

Description: This dissertation is concerned with the structure analysis of a pore-forming membrane protein, OmpC, which is one of the major proteins in the outer membrane of Escherichia coli. In order to obtain structural information it was necessary to develop a suitable technique for preparing two-dimensional crystalline arrays of this membrane protein in an unfixed, unstained and hydrated condition. Electron micrographs were recorded at exposures of less than 5 electrons/A/sup 2/ in order to avoid severe radiation damage. The resulting images were crystallographically averaged, in order to overcome the statistical limitations associated with the low electron exposures. The resulting images, which extend to a resolution of approx. 13.5 A, lend themselves to a natural interpretation that is consistent with the mass density of protein, water and lipid, prior data from 2-D and 3-D structure studies of negatively stained specimens at approx. = 20 A resolution, and published spectroscopic data on the peptide chain secondary structure.
Date: July 1, 1983
Creator: Chang, C.F.
Partner: UNT Libraries Government Documents Department

Blowup of a weak beam due to interaction with a strong beam in an electron storage ring

Description: The theoretical description of the beam-beam interaction presented here takes into account all the important features of the beam-beam phenomenon: the nonlinear beam-beam force and its dependnce on both transverse coordinates, damping of the oscillations, presence of noise in the particle motion, in particular the quantum noise in its synchrotron radiation, actual machine functions, layout and the number B of interaction points, and to some extent imperfections present in the machine. The model deals not with a separate particle, but with the beam as a whole using phase space distribution functions and the average (unperturbed and perturbed) characteristics of the bunch.
Date: July 1, 1983
Creator: Kheifets, S.
Partner: UNT Libraries Government Documents Department

Research program in elementary-particle theory, 1983. Progress report

Description: Progress is reviewed on the following topics: physics of ultra high energies and cosmology; phenomenology of particle physics; quantum field theory, supersymmetry and models of particles; and geometric formulations and algebraic models. Recent DOE reports resulting from the contract are listed. (WHK)
Date: August 1, 1983
Creator: Sudarshan, E C.G. & Ne'eman, Y
Partner: UNT Libraries Government Documents Department

Solvent Tailoring in Coal Liquefaction. Quarterly Report, November 1982-February 1983

Description: A simple kinetic model, including a first-order catalyst deactivation rate, was applied to the upgrading of coal-derived feedstocks prepared from two solvent-refined coal fractions. A catalyst deactivation mechanism was proposed which involves the adsorption and surface reaction of coke precursors on active catalytic sites. The effect of feedstock composition, temperature, and pressure on kinetic parameters and, in particular, the catalyst deactivation rate, was determined. 21 references, 6 figures, 7 tables.
Date: January 1, 1983
Creator: Tarrer, A. R.; Curtis, C. W.; Guin, J. A. & Williams, D. C.
Partner: UNT Libraries Government Documents Department

Heavy-section steel technology program. Volume 1. Quarterly progress report, January-March 1983. [PWR; BWR]

Description: A thermal-strain modification was made to the deformation-plasticity model in the ADINA-ORVIRT fracture-mechanics analysis system in order to be more applicable to combined pressure and thermal loadings. Subcontractors continued studies on crack arrest, cleavage fracture transition, and environmentally assisted crack growth. Charpy testing of state-of-the-art weld specimens in the Fourth HSST Irradiation Series was performed on unirradiated specimens and on a few irradiated specimens for scoping purposes. Finite-flaw capabilities were incorporated into the OCA-II computer code, and parametric studies were carried out to compare fracture predictions with two-dimensional and specific finite flaws. Preparations continued for thermal-shock experiment TSE-7 to be conducted in May. Preparations for the first pressurized-thermal-shock experiment continued.
Date: September 1, 1983
Creator: Pugh, C.E.
Partner: UNT Libraries Government Documents Department

Development of materials for open-cycle MHD. Quarterly report for the period ending March 1983

Description: Pacific Northwest Laboratory (PNL) is conducting an ongoing study of channel components for open-cycle, coal-fired magnetohydrodynamic (MHD) generators. Specifically, electrodes and insulators are being developed. The electrical conductivity has been measured on several compositions based on hafnium oxide, rare earth oxides, and indium oxide. Indium oxide at present appears to be the main constituent required for high conductivity. As part of the development, materials are being corrosion tested in both Montana Rosebud coal slag and potassium sulfate (K/sub 2/SO/sub 4/). The results from three coal slag tests and one K/sub 2/SO/sub 4/ test are discussed in this document.
Date: July 1, 1983
Creator: Marchant, D.D. & Bates, J.L.
Partner: UNT Libraries Government Documents Department

Creep and tensile properties of alloy 800H-Hastelloy X weldments. [HTGR]

Description: Hastelloy X and alloy 800H were joined satisfactorily by the gas tungsten arc welding process with ERNiCr-3 filler and the shielded metal arc welding process with Inco Weld A filler. Test specimens were of two types: (1) made entirely of deposited Inco Weld A and (2) machined transverse across the weldments to include Hastelloy X, filler metal (ERNiCr-3 or Inco Weld A), and alloy 800H. They were aged 2000 and 10,000 h and subjected to short-term tensile and creep tests. Inco Weld A and ERNiCr-3 are both suitable filler metals and result in welds that are stronger than the alloy 800H base metal.
Date: August 1, 1983
Creator: McCoy, H. E. & King, J. F.
Partner: UNT Libraries Government Documents Department

Minutes of the sixth annual meeting of the Panel on Reference Nuclear Data

Description: Biomedical data needs, fusion data needs, and reactor physics data needs are reviewed. The transfer of responsibilities and the status of ENSDF are discussed, and on-line data base systems are reviewed. Attendees and observers to the meeting are listed. (WHK)
Date: May 1, 1983
Creator: Burrows, T.W. & Brenner, D.S. (eds.)
Partner: UNT Libraries Government Documents Department

Windows and mirrors needed for a laser-driven photoneutralizer

Description: Rough estimates of the neutral fraction obtainable from a photoneutralizer and of the power required to operate it are presented as functions of the window and mirror performance. More precise information will become available in the future.
Date: June 22, 1983
Creator: Fink, J.H.
Partner: UNT Libraries Government Documents Department

Information for establishing bioassay measurements and evaluations of tritium exposure

Description: This report summarizes information and references used in developing regulatory guidance on programs for the bioassay of tritium as well as information useful in planning and conducting tritium bioassay programs and evaluating bioassay data. A review of literature on tritium radiobiology is included to provide a ready source of information useful for estimating internal doses of tritium and risks for the various tritium compounds and forms, including elemental (gaseous) tritium. Simplified and conservative dose conversion factors are derived and tabulated for easy reference in program planning, safety evaluations, and compliance determinations.
Date: June 1, 1983
Creator: Brodsky, A.
Partner: UNT Libraries Government Documents Department

Installation of the Light-Water Breeder Reactor at the Shippingport Atomic Power Station

Description: This report summarizes the refueling operations performed to install a Light Water Breeder Reactor (LWBR) core into the existing pressurized water reactor vessel at the Shippingport Atomic Power Station. Detailed descriptions of the major installation operations (e.g., primary system preconditioning, fuel installation, pressure boundary seal welding) are included as appendices to this report; these operations are of technical interest to any reactor servicing operation, whether the reactor is a breeder or a conventional light water non-breeder core.
Date: May 1, 1983
Creator: Massimino, R.J. & Williams, D.A.
Partner: UNT Libraries Government Documents Department

Photovoltaic-module bypass-diode encapsulation. Annual report

Description: The design and processing techniques necessary to incorporate bypass diodes within the module encapsulant are presented in this annual report. A comprehensive survey of available pad-mounted PN junction and Schottky diodes led to the selection of Semicon PN junction diode cells for this application. Diode junction-to-heat spreader thermal resistance measurements, performed on a variety of mounted diode chip types and sizes, have yielded values which are consistently below 1/sup 0/C per watt, but show some instability when thermally cycled over the temperature range from -40 to 150/sup 0/C. Based on the results of a detailed thermal analysis, which covered the range of bypass currents from 2 to 20 amperes, three representative experimental modules, each incorporating integral bypass diode/heat spreader assemblies of various sizes, were designed and fabricated. Thermal testing of these modules has enabled the formation of a recommended heat spreader plate sizing relationship. The production cost of three encapsulated bypass diode/heat spreader assemblies were compared with similarly rated externally-mounted packaged diodes. An assessment of bypass diode reliability, which relies heavily on rectifying diode failure rate data, leads to the general conclusion that, when proper designed and installed, these devices will improve the overall reliability of a terrestrial array over a 20 year design lifetime.
Date: June 20, 1983
Partner: UNT Libraries Government Documents Department

Algae from the arid southwestern United States: an annotated bibliography

Description: Desert algae are attractive biomass producers for capturing solar energy through photosynthesis of organic matter. They are probably capable of higher yields and efficiencies of light utilization than higher plants, and are already adapted to extremes of sunlight intensity, salinity and temperature such as are found in the desert. This report consists of an annotated bibliography of the literature on algae from the arid southwestern United States. It was prepared in anticipation of efforts to isolate desert algae and study their yields in the laboratory. These steps are necessary prior to setting up outdoor algal culture ponds. Desert areas are attractive for such applications because land, sunlight, and, to some extent, water resources are abundant there. References are sorted by state.
Date: June 1, 1983
Creator: Thomas, W. H. & Gaines, S. R.
Partner: UNT Libraries Government Documents Department

Stress studies in EFG. Fourth quarterly progress report, April 1, 1983-June 30, 1983

Description: Stress distributions have been calculated for a creep law predicting a higher rate of plastic deformation than modeled in earlier studies. The expected reduction in stresses is obtained, although quantitative results are not yet available because of difficulties in obtaining convergent solutions. Improved schemes for calculating growth system temperature distributions are being evaluated in a new subtask started at MIT. Other work in temperature field modeling has examined the possibility of using horizontal temperature gradients to influence stress distributions in ribbon. The defect structure of 10 cm wide ribbon grown in the cartridge system has been examined. A new feature is identified from an examination of cross-sectional micrographs. It consists of high density dislocation bands extending through the ribbon thickness. A four-point bending apparatus has been constructed for high temperature (greater than or equal to 1000/sup 0/C) study of the creep response of silicon, and will be used to generate defects for comparison with as-grown defects in ribbon. Another subtask has been started in collaboration with the University of Illinois which will examine the feasibility of laser interferometric techniques for sheet residual stress distribution measurement. The mathematical formalism for calculating residual stress from changes in surface topology caused by an applied stress in a rectangular specimen has been developed, and the system for laser interferometric measurement to obtain surface topology data has been successfully tested on CZ silicon. Testing and calibration of different fiber optics temperature sensor configurations are underway.
Date: August 15, 1983
Partner: UNT Libraries Government Documents Department

Synthesis and Characterization of Several Molybdenum Chloride Cluster Compounds

Description: Investigation into the direct synthesis of Mo/sub 4/Cl/sub 8/(P(C/sub 2/H/sub 5/)/sub 3/)/sub 4/ from Mo/sub 2/(OAc)/sub 4/ led to a synthetic procedure that produces yields greater than 80%. The single-crystal structure disclosed a planar rectangular cluster of molybdenum atoms. Metal-metal bond distances suggest that the long edges of the rectangular cluster should be considered to be single bonds and the short metal-metal bonds to be triple bonds. This view is reinforced by an extended Hueckel calculation. Attempts to add a metal atom to Mo/sub 4/Cl/sub 8/(PR/sub 3/)/sub 4/ to form Mo/sub 5/Cl/sub 10/(PR/sub 3/)/sub 3/ led instead to a compound with the composition Mo/sub 8/Cl/sub 16/(PR/sub 3/)/sub 4/. Solution and reflectance uv-visible spectra and x-ray photoelectron spectra suggest that tetranuclear molybdenum units are present. The facile reaction between Mo/sub 8/Cl/sub 16/(PR/sub 3/)/sub 4/ and PR/sub 3/ imply that the linkage between tetrameric units is weak.
Date: June 1, 1983
Creator: Beers, William Winder
Partner: UNT Libraries Government Documents Department

Minimum-B mirrors plus EBT principles

Description: Electrons are heated at the minimum-B location(s) created by the multiple field and the toroidal field. Resulting hot electrons can assist plasma confinement by (i) providing mirror, (ii) creating azimuthally symmetric toroidal confinement, or (iii) creating a modified bumpy torus.
Date: August 1, 1983
Creator: Yoshikawa, S.
Partner: UNT Libraries Government Documents Department

FASTBUS Diagnostic Language users manual. Version 3(74)

Description: FASTBUS Diagnostic Language (FDL) is an interactive interpretive language designed to aid the engineer or physicist/user in the testing and debugging of FASTBUS modules and systems. Since FASTBUS systems involve a variety of devices and data paths, it is frequently more efficient to utilize a high-level language system such as FDL for diagnostics, rather than to develop device-specific programs. FDL can also be used to a limited extent for both device control and data acquisition.
Date: July 1, 1983
Creator: Lesny, D.
Partner: UNT Libraries Government Documents Department

Legionnaires' Disease Bacterium in power-plant cooling systems: Phase 1. Final report

Description: A survey was undertaken of the distribution, density, viability, and infectivity of Legionnaires' Disease Bacteria (Legionella) in power plant cooling systems. Water samples were collected during each of the four seasons at various locations within each of nine power plants and from ambient waters at each site. Measurements of a number of physical and chemical characteristics were made, and Legionella profiles (density, viability, and infectivity for guinea pigs) were obtained. Legionella were detected in nearly all samples. Water from closed-cycle cooling systems frequently had lower densities of Legionella than the ambient water. Nonetheless, infectious Legionella, as defined by their isolation from inoculated guinea pigs, were significantly more likely to be found in samples from the plant-exposed water of closed-cycle plants than in samples from once-through plants or in ambient samples. A new species (L. oakridgensis) was initially isolated from two of the sites, and it has since been found to have a widespread distribution. Two other organisms found to cause illness in guinea pigs may also be new species. Phase II of the project involves investigating possible cause/effect relationships between physicochemical variables and Legionella. This work may contribute toward eventual control techniques for this pathogen.
Date: June 1, 1983
Creator: Christensen, S.W.; Solomon, J.A.; Gough, S.B.; Tyndall, R.L. & Fliermans, C.B.
Partner: UNT Libraries Government Documents Department

Neutron activation of four ferritic steels

Description: Four ferritic steels (Table 1) were compared using two simplified fusion reactor geometries. In the MFE geometry, a 14.1-MeV point source was centered inside a 5 m radius vessel. The 2 cm thick first wall was surrounded by a reflector consisting of 78 cm Li, 18 cm graphite, 2 cm B/sub 4/C, and a 10 cm thick outer wall. In the ICF geometry, the neutron source was in a compressed plasma (rho R = 3 g/cm/sup 2/), and the region between 0.5 and 2.0 m was filled with Li at 50% of the natural density.
Date: June 1, 1983
Creator: Blink, J.A.
Partner: UNT Libraries Government Documents Department

Materials and Molecular Research Division annual report 1982

Description: This report is divided into: materials sciences, chemical sciences, nuclear sciences, fossil energy, advanced isotope separation technology (AISI), energy storage, magnetic fusion energy (MFE), nuclear waste management, and work for others (WFO). Separate abstracts have been prepared for all except AIST, MFE, and WFO. (DLC)
Date: May 1, 1983
Partner: UNT Libraries Government Documents Department

Two-stage precipitation of neptunium (IV) oxalate

Description: Neptunium (IV) oxalate was precipitated using a two-stage precipitation system. A series of precipitation experiments was used to identify the significant process variables affecting precipitate characteristics. Process variables tested were input concentrations, solubility conditions in the first stage precipitator, precipitation temperatures, and residence time in the first stage precipitator. A procedure has been demonstrated that produces neptunium (IV) oxalate particles that filter well and readily calcine to the oxide.
Date: July 1, 1983
Creator: Luerkens, D. W.
Partner: UNT Libraries Government Documents Department

Waste-incineration resource-recovery system for Dayco Corporation and Colleton County, South Carolina: feasibility study

Description: The development of an alternative fuel brought about by the chemical changes of solid waste materials in the presence of heat is addressed. The pyrolyzates predominantly will be carbon monoxide (low-Btu gas) and carbon particles, with carbon monoxide representing about 75 to 80% of the total. The low-Btu gas will be used to replace and/or as a substitute for such fossil fuels as natural gas and fuel oil. From a technical and economical viewpoint, it is suggested that the low-Btu gas be used as an alternative energy source. Because of existing local and industrial problems, a joint effort was formulated to confront these problems. This effort concluded that the quantity and quality of the local solid waste was sufficient to generate an alternative energy source for use by local industry. This approach will extend the county landfill for years and replace more expensive energy with a less expensive, alternative energy. A comprehensive analysis was used to develop the alternative energy source that successfully met local technical and economical parameters.
Date: September 1, 1983
Partner: UNT Libraries Government Documents Department

Depositional setting, structural style, and sandstone distribution in three geopressured geothermal areas, Texas Gulf Coast

Description: Three areas in the Texas Gulf Coastal Plain were studied using electric logs and seismic-reflection data to interpret their depositional and structural history and to compare their potential as geopressured-geothermal reservoirs. The Cuero study area, on the lower Wilcox (upper Paleocene) growth-fault trend, is characterized by closely and evenly spaced, subparallel, down-to-the-basin growth faults, relatively small expansion ratios, and minor block rotation. Distributary-channel sandstones in the geopressured lower Wilcox Group of the South Cook fault block appear to be the best geothermal aquifers in the Cuero area. The Blessing study area, on the lower Frio (Oligocene) growth-fault trend, shows wider and more variable fault spacing and much greater expansion ratios and block rotation, particularly during early Frio time. Thick geopressured sandstone aquifers are laterally more extensive in the Blessing area than in the Cuero area. The Pleasant Bayou study area, like the Blessing area, is on the Frio growth-fault trand, and its early structural development was similar rapid movement of widely spaced faults resulted in large expansion ratios and major block rotation. However, a late-stage pattern of salt uplift and withdrawal complicated the structural style. Thick geopressured lower Frio sandstone aquifers are highly permeable and laterally extensive, as in the Blessing area. In all three areas, geopressured aquifers were created where early, rapid movement along down-to-the-basin growth faults juxtaposed shallow-water sands against older shales, probably deposited in slope environments. Major transgressions followed the deposition of reservoir sands and probably also influenced the hydraulic isolation that allowed the build up of abnormal pressures. 26 refs., 49 figs., 8 tabs.
Date: January 1, 1983
Creator: Winker, C. D.; Morton, R. A.; Ewing, T. E. & Garcia, D. D.
Partner: UNT Libraries Government Documents Department
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