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Encapsulation of UC--PuC mixture for calorimetric study

Description: Tantalum capsules lined with tantalum carbide were loaded with a mixture of uranium carbide-20 wt% plutonium carbide and sealed with an electron beam weld for use in Argonne National Laboratory calorimetric studies of reactor fuels. Experimental welding tests were made to determine optimum welding parameters. Special equipment available only at LLL was used and techniques were developed to perform the loading and welding operations without exposure to moisture or oxygen and with complete containment of the radioactive particles. Three capsules were successfully loaded, welded, tested, and delivered to ANL.
Date: December 28, 1976
Creator: Armstrong, R. E. & Link, R. P.
Partner: UNT Libraries Government Documents Department

Physiopathology of blood platelets and development of platelet substitutes. Progress report, August 1, 1975--July 31, 1976

Description: Progress is reported on studies on the physiology of blood platelets in thrombocytopenic patients and rabbits. Methods for the detection of platelet antibodies and the preservation of platelets in vitro were investigated. Studies on the effect of low doses of x irradiation (up to 1000 R) on platelet function indicate that platelets exposed to ionizing radiation have increased functional activity. A list is included of publications that report the results of the studies in detail.
Date: April 28, 1976
Creator: Baldini, M G
Partner: UNT Libraries Government Documents Department

Apparatus for spot welding sheathed thermocouples to the inside of small-diameter tubes at precise locations

Description: Equipment and procedures used to spot weld tantalum- or stainless-steel-sheathed thermocouples to the inside diameter of Zircaloy tubing to meet the requirements of the Multirod Burst Test (MRBT) Program at ORNL are described. Spot welding and oxide cleaning tools were fabricated to remove the oxide coating on the Zircaloy tubing at local areas and spot weld four thermocouples separated circumferentially by 90/sup 0/ at any axial distribution desired. It was found necessary to apply a nickel coating to stainless-steel-sheathed thermocouples to obtain acceptable welds. The material and shape of the inner electrode and resistance between inner and outer electrodes were found to be critical parameters in obtaining acceptable welds.
Date: June 28, 1976
Creator: Baucum, W. E. & Dial, R. E.
Partner: UNT Libraries Government Documents Department

Neutral currents and parity breakdown in atomic transitions: three proposed experiments

Description: This paper describes three proposed experiments for observing the breakdown of parity in atomic transitions due to the exchange of neutral, parity-violating currents arising from some of the new gauge models (e.g., the Weinberg model) for the weak interaction. The experiments are based on exploiting a suggestion, by Bouchiat and Bouchiat, that modern laser technology be utilized to produce intense, monochromatic, and polarized photon beams with which to excite forbidden atomic transitions of the basic form parallel ns/sup 1///sub 2/ broken bracket ..-->.. parallel n's/sup 1///sub 2/ broken bracket. The asymmetries (of the order of 10/sup -4/) in the de-exitation processes then signal the presence of the parity-violating components due to the neutral currents. In all three experiments suggested here, the use of multiple (uncollimated)atomic beams as targets forms a basic part, and their advantages over a temperature-equilibrium vapor are described. The first experiment uses /sup 55/Cs atomic beams as a target; the second uses /sup 37/Rb in conjunction with a superstrong magnetic field (approximately 80 kG); the third uses /sup 81/Tl and requires frequency doubling of the exciting laser beam. All three experiments appear to be quite feasible, and, given the requisite equipment (much of which is or soon will be commercially available), they could yield definitive results in a period of a few months.
Date: June 28, 1976
Creator: Bloom, S. D.
Partner: UNT Libraries Government Documents Department

Stress analyses of perforated flat plates under in-plate loadings

Description: Strain-gaged flat plates having one, two, three, and five closely spaced holes were tested under uniaxial and 1:1 biaxial loading conditions. The experimental results of these tests were compared with corresponding calculated values obtained using the computer program TABLES, which was developed at Battelle-Columbus Laboratories. The study was conducted (1) to obtain highly reliable experimental data that can be used in the design of penetrations in vessels having large radii of curvature, (2) to evaluate the capability of the computer program TABLES for accurately predicting the stresses in perforated flat plates, (3) to complete the initial step leading toward the planned development of a method of analysis for clusters of nozzles attached to pressure vessels, and (4) to investigate the stress states in regions of closely space holes. The comparisons of calculated and experimental stresses were in good agreement, and the method of analysis was found to be capable of accurately predicting the complex state of stress in the vicinity of the closely spaced holes.
Date: June 28, 1976
Creator: Callahan, J. P. & Bryson, J. W.
Partner: UNT Libraries Government Documents Department

Studies of encapsulation materials for terrestrial photovoltic arrays. Forth quarterly progress report, June 16, 1976--September 15, 1976

Description: A report is presented on four studies on encapsulation: (1) Evaluation of world experience and properties of materials for encapsulation of terrestrial photovoltaic arrays; (2) Definition of encapsulant service environments and test conditions; (3) Evaluation of properties of encapsulation materials; and (4) Development of accelerated and abbreviated testing mathods for predicting performance of encapsulation materials over a 20-year lifetime. (WDM)
Date: September 28, 1976
Creator: Carmichael, D. C.
Partner: UNT Libraries Government Documents Department

Influence of lateral mass efflux on free convection boundary layers in a saturated porous medium. Technical report No. 13

Description: The effects of lateral mass efflux with prescribed temperature and velocity on vertical free convection boundary layers in a saturated porous medium at high Rayleigh numbers are studied analytically. Within the framework of boundary layer theory, similarity solutions are obtained for the special case where the prescribed temperature and velocity of the fluid vary as x/sup lambda/ and x/sup (lambda-1)/2/ respectively. The effects of mass efflux on surface heat transfer rate and boundary layer thickness are shown. Application to warm water discharge along a well or fissure to an aquifer of infinite extent is discussed.
Date: April 28, 1976
Creator: Cheng, P.
Partner: UNT Libraries Government Documents Department

Calculation of two-phase dispersed droplet-in-vapor flows including normal shock waves

Description: A method for calculating quasi-one-dimensional, steady-state, two-phase dispersed droplet-in-vapor flow has been developed. The technique is applicable to both subsonic and supersonic single component flow in which normal shock waves may occur, and is the basis for a two-dimensional model. The flow is assumed to be inviscid except for droplet drag. Temperature and pressure equilibrium between phases is assumed, although this is not a requirement of the technique. Example calculations of flow in one-dimensional nozzles with and without normal shocks are given and compared with experimentally measured pressure profiles for both low quality and high quality two-phase steam/water flow.
Date: July 28, 1976
Creator: Comfort, W. J.; Alger, T. W.; Giedt, W. H. & Crowe, C. T.
Partner: UNT Libraries Government Documents Department

Neutronics and mass transport in a chemical reactor associated with controlled thermonuclear fusion reactor

Description: The formation of ozone from oxygen and the dissociation carbon dioxide to carbon monoxide and oxygen is studied in a gamma-neutron chemical process blanket associated with a controlled thermonuclear reactor. Materials used for reactor tube wall will affect the efficiency of the energy absorption by the reactants and consequently the yield of reaction products. Three kinds of materials, aluminum, stainless steel and fiber (Al/sub 2/O/sub 3/)-aluminium are investigated for the tube wall material in the study.
Date: November 28, 1976
Creator: Dang, V D; Steinberg, M; Lazareth, O W & Powell, J R
Partner: UNT Libraries Government Documents Department

Laser beam trapping and propagation in cylindrical plasma columns

Description: An analysis of the scheme to heat magnetically confined plasma columns to kilovolt temperatures with a laser beam requires consideration of two propagation problems. The first question to be answered is whether stable beam trapping is possible. Since the laser beam creates its own density profile by heating the plasma, the propagation of the beam becomes a nonlinear phenomenon, but not necessarily a stable one. In addition, the electron density at a given time depends on the preceding history of both the medium and the laser pulse. A self-consistent time dependent treatment of the beam propagation and the medium hydrodynamics is consequently required to predict the behavior of the laser beam. Such calculations have been carried out and indicate that propagation of a laser beam in an initially uniform plasma can form a stable filament which alternately focuses and defocuses. An additional question that is discussed is whether diffractive losses associated with long propagation paths are significant.
Date: May 28, 1976
Creator: Feit, M. D. & Fleck, J. A., Jr.
Partner: UNT Libraries Government Documents Department

Standpipe-bubbler pump level-control study sodium temperature distribution (task B)

Description: A thermal analysis was performed to establish requirements for a heating system for the standpipe bubbler sufficient to maintain the sodium in the standpipe in a liquid condition over the range of operating conditions. There are very few formal requirements on operating limits or hardware selection. Therefore, consideration was given to standard types of equipment employed in a conventional manner. The recommended heating system consists of metal-sheathed resistance heaters with three units being mounted on standoffs and equally spaced around the pipe. The heaters would be covered by a layer of insulation having both interior and exterior coverings of reflective metal sheathing. The pipe temperature would be monitored by thermocouples, and the heaters would be turned on and off on a cycle of approximately 4 hours to maintain the pipe at a temperature of 800/sup 0/F +- 50/sup 0/F.
Date: May 28, 1976
Creator: Forbes, F.E.
Partner: UNT Libraries Government Documents Department

Dip coating process. Quarterly report No. 3, March 19, 1976--June 18, 1976

Description: The objective of this research program is to investigate the technical and economic feasibility of producing solar-cell quality sheet silicon by dip-coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon. Of the various substrate materials dip-coated this reporting period, mullite appears, at this time, to best satisfy the requirements of this research program. Dip-coating experiments continue to demonstrate that layer thickness and grain size are dependent on and can be controlled by pulling rate and melt temperature. Crystalline grains as large as 1 mm wide and 2 cm or more long can consistently be grown in layers 35 to 50 ..mu.. meters thick. (WDM)
Date: June 28, 1976
Creator: Heaps, J. D.; Maciolek, R. B.; Scott, M. W.; Wolner, H. A. & Nelson, L. D.
Partner: UNT Libraries Government Documents Department

Dip coating process. Annual report No. 1, October 21, 1975--September 17, 1976

Description: The objective of this research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by dip-coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon. The dip-coating methods studied were directed toward a minimum-cost process with the ultimate objective of producing solar cells with a conversion efficiency of 10 percent or greater. The technique shows excellent promise for low-cost, labor-saving, scale-up potentialities and would provide an end product of sheet silicon with a rigid and strong supportive backing. An experimental dip-coating facility was designed and constructed, and, using this facility, several substrates have been successfully dip-coated with areas as large as 25 cm/sup 2/ and thicknesses of 12 ..mu..m to 250 ..mu..m. There appears to be no serious limitation on the area of a substrate that could be coated. Of the various substrate materials dip-coated this reporting period, mullite appears, at this time, to best satisfy the requirement of this research program. An inexpensive process has been developed for producing mullite in the desired geometry, thus satisfying the cost objectives of the program.
Date: September 28, 1976
Creator: Heaps, J. D.; Maciolek, R. B.; Zook, J. D.; Harrison, W. B.; Scott, M. W.; Hendrickson, G. et al.
Partner: UNT Libraries Government Documents Department

Dip coating process. Silicon sheet growth development for the large-area silicon sheet task of the low-cost silicon solar array project. Quarterly report No. 4, September 17, 1976--December 17, 1976

Description: The objective of this research program is to investigate the technical and economic feasibility of producing solar cell-quality sheet silicon by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. With the present dip coating facility, pulling rates of 5 to 7 cm/min are most likely to produce layers of the crystalline quality from which high efficiency solar cells can be fabricated. At a pulling rate of 6 cm/min, it is possible to achieve smooth 50-..mu..m thick layers, with grains as large as 2.5-mm wide, generally extending the entire length of the substrate. At pulling rates less than 6 cm/min, single grains as large as 4 mm in width have been observed. Substrates held at an angle of 45/sup 0/ to the surface of the melt during dipping produced layers qualitatively similar to the vertical dipped layers, but they show some potential for improved coating uniformity. Diffractometer measurements on several samples showed that the strongest diffraction peak was from the silicon 220 plane which is about 10/sup 0/ from the sample surface. The (110) surfaces have been found to be dominant in the EFG and dendritic material, and it appears this is a general characteristic of sheet-grown silicon. Mullite substrates containing an excess of SiO/sub 2/ have been shown to match the thermal expansion coefficient of silicon. Mullite, however,dissolves slightly in the silicon melt, adding aluminum impurities to the silicon layers. A preliminary Ion Beam Microprobe analysis revealed that the aluminum concentration measured in three samples of typical dip-coated silicon layers correlated correctly with the measured restitivies. Photodiodes were made on a number of silicon on ceramic (SOC) layers, and results of performance tests are discussed.
Date: December 28, 1976
Creator: Heaps, J. D.; Zook, J. D.; Maciolek, R. B.; Schuldt, S.; Schuller, T. L.; Nelson, L. D. et al.
Partner: UNT Libraries Government Documents Department

Web-dendritic ribbon growth. Quarterly report, October 1976--December 15, 1976

Description: A report of the fifth quarter's work on the web-dendritic ribbon growth at the University of South Carolina is presented. A brief description of the work initiated and carried out during this period to meet the program goals is given along with a copy of the Program Plan covering the entire period of the contract. The web growth portion of this program was spent in the design, installation and testing of a new furnace geometry for the growth of dendritic web ribbon. The new installation was completed and the testing 90% accomplished. Results of the testing to determine the effect of the relative position of the r.f. coil with respect to the susceptor on the thermal profile in the melt are described. The one-dimensional thermal model has been used to determine the relationship between growth rate, web thickness, and mensicus height for stable growth. The results of this analysis are also given. An analysis was completed of the thermal radiation from the meniscus including the effect of the curvature of the meniscus with the results indicating that inclusion of the curvature leads to approximately a 10% increase in the radiation loss.
Date: December 28, 1976
Creator: Hilborn, R. B. Jr. & Faust, J. W. Jr.
Partner: UNT Libraries Government Documents Department

[News Clip: Music blind]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: December 28, 1976, 5:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Nuclear chemistry and geochemistry research. Carnegie Institute of Technology and Carnegie--Mellon University. Summary report

Description: A summary is presented of the activities and results of research in nuclear chemistry, nuclear geochemistry, nuclear cosmochemistry, and other minor areas from 1950 to 1976. A complete listing is given of publications, doctoral dissertations, and reports resulting from the research. A chronological list provides an overview of the activities at any particular time. (JSR)
Date: May 28, 1976
Creator: Kohman, T. P.
Partner: UNT Libraries Government Documents Department

Basal Ottawa Limestone, Chattanooga Shale, Floyd Shale, Porters Creek Clay, and Yazoo Clay in parts of Alabama, Mississippi and Tennessee as potential host rocks for underground emplacement of waste

Description: Impermeable rock units, preferably at least 500 feet thick and lying 1000 to 3000 feet below land surface, were sought in the region consisting roughly of the western /sup 3///sub 5/ths of Tennessee and the northern /sup 3///sub 5/ths of Alabama and Mississippi. All rock sequences, Cambrian through Eocene, were examined in varying detail, except the Cretaceous Selma Chalk and except the diapiric salt. These rocks were studied for their relative impermeable homogeneity, their continuity, their background of structural and seismic stability and their hydrologic associations. The Central Mississippi Ridge of north-central Mississippi is overlain by a long-stable mass of Porters Creek Clay 500-700 feet thick, in an area roughly 50-60 miles wide and about 150 miles long. The Yazoo Clay, where best developed in the west-central and southwest part of Mississippi, is in the 400-500 foot thickness range, but locally exceeds 500 feet. The entire area mapped is underlain by the Louann Salt which has produced many deep-seated salt domes and numerous piercement salt domes. Salt flow has complicated shallow structural geology throughout that area. The Chattanooga Shale rarely exceeds 60 feet in thickness in the region studied and is generally much thinner and is absent in many places. In the lower part of the Middle Ordovician (Ottawa Megagroup), the Murphreesboro and associated dense limestones appear to offer a potential disposal unit 250-400 feet thick, having the advantages of rock competency and freedom from association with prolific aquifers in the overburden or beneath. Other less conspicuous stratigraphic units are reviewed.
Date: February 28, 1976
Creator: Mellen, F. F.
Partner: UNT Libraries Government Documents Department

Fundamental studies of metal fluorination reactions. Annual progress report

Description: Solid-state electrochemical methods are being used to determine structural, thermodynamic, and transport properties in materials pertinent to the fluorination of metals at elevated temperatures. The solubility and diffusivity of fluorine in solid metals (initially nickel) are being studied by a potentiostatic electrochemical procedure by which changes in an impressed cell voltage induces changes in the activity of fluorine at a metal/electrolyte interface while the recording of the resulting cell current as a function of time can be interpreted to yield the desired quantities. Defect structures in metal fluoride compounds (initially NiF/sub 2/ and PbF/sub 2/) are being studied through measurements and interpretation of the electrical conductivity. The variation in the conductivities of the pure and impurity-doped compound as a function of fluorine activity can be interpreted to establish the partial ionic and electronic conductivities of the compounds, and the concentrations and mobilities of the carriers. Finally, a CaF/sub 2/-electrolyte probe (gauge) is being developed for the measurement of fluorine activities in gases at elevated temperatures. The literature has been searched and studied. Experimental materials have been ordered and two high-temperature electrochemical systems have been constructed and tested. The electrical instrumentation has been tested and calibrated. A porous graphite electrode was found to be effective in fixing and transmitting fluorine activities which are set electrochemically at one graphite/electrolyte interface. This preliminary success establishes the intended means for the variation of fluorine activity in the electrical and conductivity measurements. Coexistence electrodes of nickel plus nickel fluoride at 850-950/sup 0/C have been found to remain essentially reversible despite current passage up to significant current densities. (auth)
Date: January 28, 1976
Creator: Rapp, R. A.
Partner: UNT Libraries Government Documents Department