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Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, October 1, 1979-September 30, 1980. [Ethane Elimination]

Description: The 1,1-reductive elimination of ethane from three cis-bis(phosphine)-dimethylpalladium complexes, L/sub 2/Pd(CH/sub 3/)/sub 2/ (L = PPh/sub 3/, PPh/sub 2/,CH/sub 3/ and L/sub 2/ = Ph/sub 2/PCH/sub 2/CH/sub 2/PPh/sub 2/), and three trans analogs (L = PPh/sub 3/, PPh/sub 2/CH/sub 3/ and L/sub 2/ = 2,11-bis(diphenylphosphinomethyl)benzo(c)phenanthrene (TRANSPHOS)) was carried out. The three cis complexes underwent reductive elimination in the presence of coordinating solvents (DMSO, DMF, and THF)… more
Date: September 1, 1980
Creator: Stille, J. K.
Partner: UNT Libraries Government Documents Department
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Planetary-Wave Behavior and Arctic Air Pollution

Description: An attempt was made to relate episodes of air pollution at Barrow, Alaska, containing vanadium, to the behavior of planetary waves in middle and high latitudes. A stationarity index for planetary waves is defined as the ratio between amplitudes computed from monthly mean maps and the mean amplitudes computed on a daily basis and averaged over the same month, irrespective of phase angle. Longitude-time sections of 500-mb height anomalies at various latitudes are related to vanadium pollution epi… more
Date: January 1, 1979
Creator: Reiter, Elmar R.
Partner: UNT Libraries Government Documents Department
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Novel Concepts in Electrochemical Solar Cells. Third Quarterly Progress Report, November 15, 1979-January 15, 1980. [Molten Salt Electrolytes]

Description: Efforts have been primarily directed toward evaluation of the room temperature molten salt electrolyte in terms of its overall performance for photovoltaic cells. Mass transport processes may prove to be the rate-limiting factor for such electrolytes, unless the concentration of the photo-active redox component can be increased and the solvent viscosity reduced. Acid-base surface chemistry of n-GaAs as occurs in aqueous systems, has been found present and its consequences will be further explor… more
Date: January 1, 1980
Creator: DuBow, J.; Job, R. & Krishnan, R.
Partner: UNT Libraries Government Documents Department
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Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes

Description: We are making progress on our investigation of the mechanism of olefin exchange with Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8}. We are probing this system by kinetic study of the reaction of Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8} with butyl acrylate (BA) under various pressures of ethylene.
Date: May 1, 1992
Creator: Norton, J.R.
Partner: UNT Libraries Government Documents Department
open access

Wind Load Reduction for Heliostats

Description: This report presents the results of wind-tunnel tests supported through the Solar Energy Research Institute (SERI) by the Office of Solar Thermal Technology of the US Department of Energy as part of the SERI research effort on innovative concentrators. As gravity loads on drive mechanisms are reduced through stretched-membrane technology, the wind-load contribution of the required drive capacity increases in percentage. Reduction of wind loads can provide economy in support structure and helios… more
Date: May 1, 1986
Creator: Peterka, J. A.; Hosoya, N.; Bienkiewicz, B. & Cermak, J. E.
Partner: UNT Libraries Government Documents Department
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Exploratory Study of Metal Vapor Lasers Operating in the Ultra-Violet at Kilowatt Power Levels. Final Report, June 1, 1975--March 31, 1979

Description: Cw laser action has been extended down to 220 nm. Moreover, cw oscillation has been obtained on twenty additional transitions in the spectral range between 220 and 320 nm. Ultra-violet laser thresholds as low as 2 A have been observed. In comparison, rare gas ion lasers require 20 to 50 A to reach threshold. Metals of interest are sputtered into the discharge giving metal densities of 10/sup 14/ atoms cm/sup -3/ without using external ovens or discharge heating. Recent attempts to scale the out… more
Date: March 1, 1979
Creator: Collins, G.J.
Partner: UNT Libraries Government Documents Department
open access

Role of Polycrystallinity in Cdte and Cuinse Sub 2 Photovoltaic Cells

Description: The polycrystalline nature of thin-film CdTe and CuInSe{sub 2} solar cells continues to be a major factor in several individual losses that limit overall cell efficiency. This report describes progress in the quantitative separation of these losses, including both measurement and analysis procedures. It also applies these techniques to several individual cells to help document the overall progress with CdTe and CuInSe{sub 2} cells. Notably, CdTe cells from Photon Energy have reduced window phot… more
Date: January 1, 1991
Creator: Sites, J.R. (Colorado State Univ., Fort Collins, CO (United States))
Partner: UNT Libraries Government Documents Department
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Mean and Peak Wind Load Reduction on Heliostats

Description: This report presents the results of wind-tunnel tests supported through the Solar Energy Research Institute (SERI) by the Office of Solar Thermal Technology of the US Department of Energy as part of the SERI research effort on innovative concentrators. As gravity loads on drive mechanisms are reduced through stretched-membrane technology, the wind-load contribution of the required drive capacity increases in percentage. Reduction of wind loads can provide economy in support structure and helios… more
Date: September 1, 1987
Creator: Peterka, J. A.; Tan, L.; Bienkiewcz, B. & Cermak, J. E.
Partner: UNT Libraries Government Documents Department
open access

Solar Thermal Electric Power Systems With Line-Focus Collectors. Final Report

Description: Electric power generation by conventional Rankine cycle heat engines with heat supplied by line-focus solar collectors was investigated. The objectives of the study were: (1) determine which of four types of line-focus solar collectors coupled with turbine-generators of conventional design has the potential to produce low-cost electric power with thermal energy in 100 to 300/sup 0/C range; (2) develop performance and cost relationships for organic Rankine cycle engines for power generation capa… more
Date: December 1, 1978
Creator: Duff, W. S.; Karaki, S.; Shaner, W. W.; Wilbur, P. J.; Somers, E. V.; Grimble, R. E. et al.
Partner: UNT Libraries Government Documents Department
open access

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes

Description: We have obtained a neutron diffraction data set for Os{sub 2}(CO){sub 8}({mu}-C{sub 2}H{sub 4}). While the structure is still being solved, it is already clear that the hybridization at both of the ethylene carbons is sp{sup 3}. Our first interpretation of our liquid crystal NMR results had suggested a very acute H-C-H angle. We have also obtained {sup 13}C liquid crystal data for Os{sub 2}(CO){sub 8}({mu}-C{sub 2}H{sub 4}). Liquid crystal NMR ({sup 13}C as well as {sup 1}H) spectra have been o… more
Date: January 1, 1989
Creator: Norton, J.R.
Partner: UNT Libraries Government Documents Department
open access

Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, June 1, 1978-September 30, 1979

Description: The coupling reaction of benzyl halides and organolithium, organotin, or Grignard Reagents is catalyzed by palladium. The sequence of events in the catalytic cycle is oxidative addition of the benzyl halide to palladium(0), methathesis by the organometallic reagent to give a benzyl methyl palladium(II) complex, oxidative addition of the benzyl halide to give a palladium(IV) complex, and reductive elimination of benzyl and methyl to give ethylbenzene. The reductive elimination from palladium bea… more
Date: September 1, 1979
Creator: Stille, J. K.
Partner: UNT Libraries Government Documents Department
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Overburden Characterization and Post-Burn Study of the Hanna Iv, Underground Coal Gasification Site, Wyoming, and Comparison to Other Wyoming Ucg Sites

Description: Analysis of 21 post-burn cores taken from the Hanna IV UCG site allows 96 m (315 ft) of overburden to be subdivided into four local stratigraphic units. The 7.6 m (25 ft) thick Hanna No. 1 coal seam is overlain by a laterally discontinuous, 3.3 m (11 ft) thick shaley mudstone (Unit A') in part of the Hanna IV site. A more widespread, 30 m (90 ft) thick well-indurated sandstone (Unit A) overlies the A' unit. Unit A is the roof rock for both of the Hanna IV cavities. Overlying Unit A is a 33 m (1… more
Date: November 1, 1984
Creator: Marcouiller, B.A.; Burns, L.K. & Ethridge, F.G.
Partner: UNT Libraries Government Documents Department
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Rehabilitation Potential and Practices of Colorado Oil Shale Lands. Progress Report, June 1, 1978--May 31, 1979

Description: The following document is a third-year progress report for the period June 1, 1978 to May 31, 1979. The overall objective of the project is to study the effects of seeding techniques, species mixtures, fertilizer, ecotypes, improved plant materials, mycorrhizal fungi, and soil microorganisms on the initial and final stages of reclamation obtained through seeding and subsequent succession on disturbed oil shale lands. Plant growth medias that are being used in field-established test plots includ… more
Date: March 1, 1979
Creator: Cook, C.W.
Partner: UNT Libraries Government Documents Department
open access

Exploration of the Big Boulder Prospect, Larimer County, Colorado

Description: From introduction: The Big Boulder prospect is in SE 1/4 sec. 36, T.7N., R.,72W., in Tarimer County, Colorado. The prospect has been opened by four irregular trenches and shallow cuts, and a 10-foot discovery shaft. Hanley 1/4 states that 10.5 tons of beryl were produced from the Big Boulder prospect in 1936, and about 600 pounds in 1941.
Date: August 1950
Creator: Thurston, W. R.
Partner: UNT Libraries Government Documents Department
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Milk Production and Distribution in Nine Western States in the 1950s

Description: This report provides information on milk distribution and dairy cattle feeding practices in Nevada, Utah and portions of seven other adjacent states during the 1950s. The information was gathered to support the US Department of Energy's ''Offsite Radiation Exposure Review Project (ORERP).'' This project is charged with providing radiation dose estimates for residents of Nevada, Utah, and surrounding states from nuclear weapons testing conducted at the Nevada Test Site from 1951 through 1962. Th… more
Date: March 1, 1987
Creator: Ward, G. M. & Whicker, F. W.
Partner: UNT Libraries Government Documents Department
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Ornithogalum Virens as a Plant Assay for Beta and Gamma Radiation Effects

Description: The purpose of this study was to determine if the monocotyledonous angiosperm, Ornithogalum virens (Quintanilha and Cabral, 1947), could be used in such a biological assay system. After exposing O. virens plants to acute (/sup 60/Co) and chronic (/sup 137/Cs) gamma radiation and internal beta radiation (/sup 32/P), lethality (LD/sub 50/, LD/sub 100/), growth inhibition, and chromosome aberrations were investigated. The LD/sub 50/ and LD/sub 100/ for acute gamma radiation were estimated to be be… more
Date: January 1, 1979
Creator: Herron, V J
Partner: UNT Libraries Government Documents Department
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Grassland/Atmosphere Response to Changing Climate: Coupling Regional and Local Scales. Final Report

Description: The objectives of the study were: to evaluate the response of grassland ecosystems to atmospheric change at regional and site scales, and to develop multiscaled modeling systems to relate ecological and atmospheric models with different spatial and temporal resolutions. A menu-driven shell was developed to facilitate use of models at different temporal scales and to facilitate exchange information between models at different temporal scales. A detailed ecosystem model predicted that C{sub 3} te… more
Date: October 1, 1993
Creator: Coughenour, M. B.; Kittel, T. G. F.; Pielke, R. A. & Eastman, J.
Partner: UNT Libraries Government Documents Department
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Development of a gas-to-particle conversion model for use in three-dimensional global sulfur budget studies. Final report, 1 August 1991--30 June 1992

Description: A fully-parameterized model for the formation and growth of aerosols via gas-to-particle conversion has been developed and tested. A particularly significant contribution is a new method for the prediction of numbers of particles nucleated using information on the vapor source rate, relative humidity, and preexisting aerosol alone, thus eliminating the need to solve a system of coupled ODEs. Preliminary tests indicate substantial reduction in computational costs, but it is recommended that the … more
Date: August 1, 1993
Creator: Kreidenweis, S. M.
Partner: UNT Libraries Government Documents Department
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Effects of Vegetation of Radon Transport Processes in Soil: The Origins and Pathways of {Sup 222}Rn Entering Into Basement Structures. Final Report, March 15, 1987--May 15, 1993

Description: The entry rate of {sup 22}Rn into a basement structure was measured continuously. These measurements demonstrated that radon entry did not vanish even when the structure was slightly pressurized. This persistent entry has been determined to be dominated by diffusion through the floor and walls and a combination of diffusion and convection through the floor-wall joint. The highest indoor radon concentrations occurred during calm periods when the pressure differentials between the inside and outs… more
Date: August 1, 1992
Creator: Borak, T. B.
Partner: UNT Libraries Government Documents Department
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Role of polycrystallinity in CdTe and CuInSe{sub 2} photovoltaic cells. Annual subcontract report, 1 April 1991--31 March 1992

Description: The limiting role of polycrystallinity in thin-film solar calls has been reduced somewhat during the past year, and efficiencies of both CdTe and CuInSe{sub 2} cells are approaching 15%. Quantitative separation of loss mechanisms shows that individual losses, with the exception of forward recombination current, can be made comparable to their single crystal counterparts. One general manifestation of the extraneous trapping states in that the voltage of all polycrystalline thin-film cells drifts… more
Date: November 1, 1992
Creator: Sites, J. R.
Partner: UNT Libraries Government Documents Department
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Role of polycrystallinity in CdTe and CuInSe{sub 2} photovoltaic cells. Annual subcontract report, 1 April 1992--31 March 1993

Description: This report describes work to conduct several investigations of thin-film polycrystalline solar cells. (1) An analysis of high-efficiency solar cells fabricated at the University of South Florida showed significant reduction in forward recombination current, and the cells were stable over a 3-month test period. (2) Transient voltage effects were documented in a large number of polycrystalline cells and were attributed to long-lived trapping states sensitive to voltage changes near one-half open… more
Date: February 1, 1994
Creator: Sites, J. R.
Partner: UNT Libraries Government Documents Department
open access

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes. Final report

Description: Assignment of the vibrational modes Of Os{sub 2}(CO){sub 8}(CHCH{sub 3}) and Os(CO){sub 4}(C{sub 2}H{sub 4)} has given fingerprint vibrational spectra for the following species when chemisorbed on metal catalyst surfaces: ethylidene and ethylene bound in a metallacyclopropane mode. The formation and fragmentation of diosmacyclobutanes have been shown to involve slippage of the outgoing olefin onto a single osmium, and associative exchange of the olefin from that site. The incorporation of vinyl… more
Date: April 25, 1994
Creator: Norton, J. R.
Partner: UNT Libraries Government Documents Department
open access

Diosmacycloalkanes as Models for the Formation of Hydrocarbons From Surface Methylenes. Progress Report, November 1, 1991--October 31, 1992

Description: We are making progress on our investigation of the mechanism of olefin exchange with Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8}. We are probing this system by kinetic study of the reaction of Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8} with butyl acrylate (BA) under various pressures of ethylene.
Date: May 1, 1992
Creator: Norton, J. R.
Partner: UNT Libraries Government Documents Department
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