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Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol

Description: Syrian golden hamsters of both sexes were exposed to aerosols of ZrO/sub 2/ containing PuO/sub 2/. The starting material in the aerosol generator also had a small amount of /sup 57/Co added as a tracer. The mixture of all three constituents was nebulized and the droplets passed through a heating column at 1000/sup 0/C. Aerosol sampling was accomplished with a cascade impactor and electrostatic precipitator. The median aerodynamic diameters in all inhalation runs were approximately 2 ..mu..m wit… more
Date: January 1, 1978
Creator: Thomas, R. G. & Smith, D. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electronic band structure and optical properties of the cubic, Sc, Y and La hydride systems

Description: Electronic band structure calculations are used to interpret the optical spectra of the cubic Sc, Y and La hydride systems. Self-consistent band calculations of ScH/sub 2/ and YH/sub 2/ were carried out. The respective joint densities of states are computed and compared to the dielectric functions determined from the optical measurements. Additional calculations were performed in which the Fermi level or band gap energies are rigidly shifted by a small energy increment. These calculations are t… more
Date: January 1, 1980
Creator: Peterman, D. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Redox reactions involving chromium, plutonium, and manganese in soils

Description: Plutonium speciation in soils is discussed. Chromium was selected as a model for studying soil Pu. Similarities between Cr and Pu are pointed out, and a hypotheses concerning Pu speciation in soils is presented. Findings from Cr oxidation studies that may be relevant to the problem of Pu oxidation in soils are discussed. (JGB)
Date: January 1, 1979
Creator: Amacher, M.C. & Baker, D.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Potential for use of high-temperature superconductors in fusion reactors

Description: The present rate of development of high-temperature superconductors (HTSs) is sufficiently rapid that there may be opportunities for their use in contemporary fusion devices such as the International Thermonuclear Experimental Reactor (ITER). The most likely 1application is for delivering power to the superconducting magnets, especially in substituting for the current leads between the temperatures of 4 K and 77K. A second possible application of HTSs is as a liquid-nitrogen-cooled power bus, c… more
Date: January 1, 1991
Creator: Hull, J.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties

Description: 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(diph… more
Date: October 7, 1991
Creator: Pang, Yi.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurements of the dependence of damage thresholds on laser wavelength, pulse duration and film thickness

Description: Results of three experiments will be described. We used 351-nm and 355-nm pulses with durations of 0.6, 1, 5 and 9 ns measure thresholds for a variety of anti-reflectance and high reflectance coatings. The functional form t/sup m/, with t the pulse duration, was used to scale fluence thresholds measured at 0.6 ns to those measured at 9.0 ns. Values of the coefficient m ranged from 0.10 to 0.51. The average value was 0.30. In the second experiment, we measured thresholds at 1064 nm, 527 nm and 3… more
Date: March 1, 1984
Creator: Rainer, F.; Vercimak, C.L.; Milam, D.; Carniglia, C.K. & Tuttle Hart, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Irradiation experiment for lithium ceramics

Description: Solid breeder materials are required in D-T fusion reactor blankets to convert fusion neutrons to tritium and thermal energy while providing some neutron shielding for the magnets. Lithium compounds such as Li/sub 2/O, LiAlO/sub 2/, Li/sub 4/SiO/sub 4/ and Li/sub 2/ZrO/sub 3/ have been proposed as solid breeder materials. Tritium is necessary to maintain the fuel supply for the D-T fusion reaction. No high burnup irradiation performance data is available for these materials in a neutron environ… more
Date: March 1, 1982
Creator: Hollenberg, G.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Organic iodine removal from simulated dissolver off-gas streams using silver-exchanged mordenite

Description: The removal of methyl iodide by absorption onto silver mordenite was studied using a simulated off-gas from the fuel dissolution step of a nuclear fuel reprocessing plant. The methyl iodide absorption of silver mordenite was examined for the effects of NO/sub x/, humidity, iodine concentration, filter temperature, and filter pretreatment. The highest iodine loading achieved in these tests has been 34 mg CH/sub 3/I per g of substrate, approximately five times less than the elemental iodine loadi… more
Date: January 1, 1980
Creator: Jubin, R. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tritium storage development. Progress report No. 12, April--June 1977. [In metal hydride; polymer impregnated tritiated concrete]

Description: Laboratory work was continued on hydriding of zirconium sponge and rod under varying conditions of temperature (400 to 900/sup 0/C) and pressure (0-1000 torr) to determine optimum conditions for the formation of hydrides with desirable mechanical properties. Titanium sponge and rod were also hydrided for comparison. Zirconium and titanium samples containing tritium were prepared and initial leach data were obtained. Leach rates for zirconium in distilled water ranged from 1.1 x 10/sup -6/ to 4.… more
Date: January 1, 1976
Creator: Colombo, P
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of an extended-burnup Mark B design. First semi-annual progress report, July-December 1978. Report BAW-1532-1. [PWR]

Description: The primary objective of this program is to develop and demonstrate an improved PWR fuel assembly design capable of batch average burnups of 45,000-50,000 MWd/mtU. To accomplish this, a number of technical areas must be investigated to verify acceptable extended-burnup fuel performance. This report is the first semi-annual progress report for the program, and it describes work performed during the July-December 1978 time period. Efforts during this period included the definition of a preliminar… more
Date: October 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/(YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 2/ (Ruby), a study of certain properties of these laser materials related to their valence-electron structures

Description: A direct method of determination of the valence-electron structure from its crystal structure has been presented by the writer at XIIth International Congress of Crystallography, at Ottawa, 1981. Here the method is applied to determine the valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/ (YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 3/ (ruby) to see how certain properties of these laser materials are related to their valence-electron structures. The first point observed is the very stron… more
Date: January 1, 1982
Creator: Yu, S. H. & Yu, L. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Removal of silica from Raft River geothermal water

Description: Lack of sufficient quantities of clean surface or near-surface water at Raft River for cooling purposes dictates that cooled geothermal fluid, effluent from the Raft River 5 MW(e) Pilot Power Plant, must also be used as condenser coolant. Prior testing revealed that a water-treatment system would be required to reduce silica and calcium concentrations of the cooling fluid. The water-treatment system specified was to use dolomitic lime for both pH adjustment and source of magnesium. The dolomiti… more
Date: June 1, 1980
Creator: Suciu, D. F. & Miller, R. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Role of groundwater oxidation potential and radiolysis on waste glass performance in crystalline repository environments

Description: Laboratory experiments have shown that groundwater conditions in a Stripa granite repository will be as reducing as those in a basalt repository. The final oxidation potential (Eh) at 70/sup 0/C for Stripa groundwater deaerated and equilibrated with crystalline granite was -0.45V. In contrast, the oxidation potential at 60/sup 0/C for Grande Ronde groundwater equilibrated with basalt was -0.40V. The reducing groundwater conditions were found to slightly decrease the time-dependent release of so… more
Date: January 1, 1985
Creator: Jantzen, Carol M. & Bibler, Ned E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hot gas desulfurization with oxides of zinc, iron, and vanadium

Description: The objective of this study is to develop an improved sorbent which can reduce H{sub 2}S levels up to 1 ppmv or less, which can stabilize zinc, and produce economically recoverable amounts of elemental sulfur during regeneration. For this purpose, the desulfurization performance of sorbents prepared by the addition of various amounts of V{sub 2}O{sub 5} to the zinc ferrite sorbent is investigated.
Date: January 1, 1992
Creator: Akyurtlu, J.F. & Akyurtlu, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts

Description: The primary objective of the project is to examine the relations between the catalytic and magnetic properties of the copper-cobalt higher alcohol synthesis catalysts. We have undertaken to investigate the magnetic character by studying the Nuclear Quadrupole resonance of copper and (Zerofield) Nuclear Magnetic Resonance of cobalt in copper cobalt catalysts.
Date: December 17, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies on transition metals and alloy Fischer-Tropsch catalysts, their electronic and bulk properties. (I: Fe/MnO; II: Fe/TiO/sub 2/; III: Fe/Mord. ). Final report, July 1, 1982-September 30, 1983

Description: The objectives were: (1) to characterize samples D1, 10% FeO/90% MnO, and D2, 48% FeO/52% MnO, under varying conditions of reduction (at 250/sup 0/C or 350/sup 0/C in H/sub 2/) and of syngas reaction 1:1 of CO:H/sub 2/ at 290/sup 0/C) and in some cases use CO only for reduction and to identify species by Moessbauer Spectroscopy and Magnetization (sigma/sub s) measurement; (2) similarly, to see if there is any metal (oxide)/support (Mordenite) interaction by the same techniques. The characteriza… more
Date: November 1, 1983
Creator: Mulay, L.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical aspects of solid state reactions in a mixed particulate ensemble and kinetics of lead zirconate formation

Description: A theoretical analysis was carried out to estimate the quasi-steady-state external mass transport by lattice, surface and gaseous diffusion in terms of the stereologically measurable microstructural parameters of a mixed powder compact. It was shown that the gaseous transport can be described by a single dimensionless quantity termed sublimation transport modulus. Using these equations, the relative importance of the alternate external transport modes can be evaluated. Experimental work determi… more
Date: September 1, 1979
Creator: Chandratreya, S.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cadmium sulfide/copper ternary heterojunction cell research. Final report, January 8, 1979-June 7, 1980

Description: Dual source, Se and CuInSe/sub 2/, coevaporation and flash evaporation of stoichiometric CuInSe/sub 2/ powder were investigated to develop a process of fabricating large area CdS/CuInSe/sub 2/ heterojunction solar cells. CuInSe/sub 2/ was seen to decompose upon evaporation, producing layered films in the dual source system. Annealing of these films and alternative dual sources have been considered. Single phase p type films have been produced but no devices have been made from such films. Flash… more
Date: January 1, 1980
Creator: Fleming, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cementitious yttria products

Description: An investigation has been made of the physical properties and formation conditions of cements formed in the yttria/salt/water system. Cementitious binders were of the nominal Y/sub 2/(OH)/sub 5/X.H/sub 2/O type (where X represents the Cl/sup -/ or NO/sub 3//sup -/). An ammonium nitrate-produced yttria cement was shown to be sinterable and was demonstrated to form very refractory castable concretes with zirconia or alumina aggregates.
Date: March 1, 1978
Creator: Holcombe, C. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Methane oxidation over dual redox catalysts

Description: The objective of this research is to develop approaches to direct catalytic oxidation of methane over oxides that are doubly doped with transition metal ions. The desired process aims at employing a double redox mechanism, where one redox couple is utilized for activation of oxygen and another for the trapping of CH{sub 3} radicals. The methyl radicals can either recombine, giving C{sub 2} hydrocarbons, or be converted, via electron transfer reaction, to carbocations. The latter species can rea… more
Date: September 1, 1989
Creator: Klier, Kamil; Herman, Richard G. & Sojka, Zbigniew
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling of Integrated Environmental Control Systems for Coal-Fired Power Plants Quarterly Report: Final Report

Description: The Integrated Environmental Control Model (IECM) was designed to permit the systematic evaluation of environmental control options for pulverized coal-fired (PC) power plants. Of special interest was the ability to compare the performance and cost of advanced pollution control systems to conventional'' technologies for the control of particulate, SO{sub 2} and NO{sub x}. Of importance also was the ability to consider pre-combustion, combustion and post-combustion control methods employed alone… more
Date: May 1, 1991
Creator: Rubin, E. S.; Salmento, J. S.; Frey, H. C.; Abu-Baker, A. & Berkenpas, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical modeling and experimental characterization of planar defects in Y sub 2 Ba sub 4 Cu sub 6+x O sub 14+x

Description: Crystallographic defects and phase transformations in the system Y{sub 2}Ba{sub 4}Cu{sub 6 + x}O{sub 14 + x}(0{le}{times}{le}4) are investigated by high resolution transmission electron microscopy (TEM) and static lattice, three dimensional Monte Carlo computer simulations. High resolution images of partially transformed (x = 2 to x = 1) material reveal a prevalence of CuO planar defects (stacking faults) associated with the transformation and an absence of disturbance to the perovskite Ba-Y-Ba… more
Date: November 1, 1990
Creator: Burmester, C. P.; Fendorf, M.; Gronsky, R. & Wille, L. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts

Description: The primary objective of the project is to examine the relations between the catalytic and magnetic properties of the copper-cobalt higher alcohol synthesis catalysts. We have undertaken to investigate the magnetic character by studying the Nuclear Quadrupole resonance of copper and (Zerofield) Nuclear Magnetic Resonance of cobalt in copper cobalt catalysts.
Date: January 14, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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