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open access

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.
open access

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.
open access

Steady-State Thermomechanical Finite Element Analysis of Elastoviscoplastic Metal Forming Processes

Description: Extrusion and rolling processes exhibiting large amounts of plastic flow are analyzed using a finite element technique that is based on a modified creeping viscous flow approximation. The technique, called the initial stress-rate method, iteratively corrects creeping viscous flow solutions to generate results that include elastic response. The momentum equations have been coupled with the energy equation to provide the capability to predict thermomechanical response during forming operations.
Date: January 1, 1977
Creator: Dawson, P.R. & Thompson, E.G.
open access

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.
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.
open access

Influence of Geometry on Natural Convection in Buildings

Description: Strong free convection airflows occur within passive solar buildings resulting from elevated temperatures of surfaces irradiated by solar energy compared with the cooler surfaces not receiving radiation. The geometry of a building has a large influence on the directions and magnitudes of natural airflows, and thus heat transfer between zones. This investigation has utilized a variety of reduced-scale building configurations to study the effects of geometry on natural convection heat transfer. S… more
Date: January 1, 1985
Creator: White, M. D.; Winn, C. B.; Jones, G. F. & Balcomb, J. D.
open access

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.
open access

Rapid estimation of /sup 226/Ra in soil for the Grand Junction RASA/UMTRA project

Description: The Radiological Survey Activities (RASA) Group of the Health and Safety Research Division at Oak Ridge National Laboratory (ORNL) is an Inclusion Survey Contractor (ISC) for the Uranium Mill Tailings Remedial Action Program (UMTRAP). The purpose of the ISC is to survey designated sites potentially contaminated with radioactive material originating from the 24 inactive uranium mill sites and make recommendations as to whether the site should be included in or excluded from further consideration… more
Date: January 1, 1986
Creator: Kark, J.B.; Borak, T.B.; Kearney, P.D. & Rood, A.S.
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))
open access

Comparative Performance of Two Types of Evacuated Tube Solar Collectors in a Residential Heating and Cooling System - The Progress Report

Description: Two types of evacuated tube solar collectors have been operated in space heating, cooling and domestic hot water heating systems in Colorado State University Solar House I. An experimental collector from Corning Glass Works supplied heat to the system from January 1977 through February 1978, and an experimental collector from Philips Research Laboratory, Aachen, which is currently in use, has been operating since August 1978. A flat absorber plate inside a single-walled glass tube is used in th… more
Date: January 1, 1979
Creator: Conway, T. M.; Duff, W. S.; Loef, G. O. G. & Pratt, R. G.
open access

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.
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.
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.
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.
open access

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.
open access

Comparison of the Response of a Nai Scintillation Crystal With a Pressurized Ionization Chamber as a Function of Altitude, Radiation Level and RA-226 Concentration

Description: The Grand Junction Uranium Mill Tailings Remedial Action-Radiological Survey Activities Group (UMTRA-RASA) program employs a screening method in which external exposure rates are used to determine if a property contaminated with uranium mill tailings is eligible for remedial action. Portable NaI detectors are used by survey technicians to locate contaminated areas and determine exposure rates. The exposure rate is calculated using a regression equation derived from paired measurements made with… more
Date: January 1, 1986
Creator: Provencher, R.; Smith, G.; Borak, T.B. & Kearney, P.
open access

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.
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.
open access

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.
open access

Characterization of Fly Ash From Coal Combustion

Description: Fly ash derived from coal combustion contains predominantly spherical particles which consist of an insoluble aluminosilicate glass containing several mineral impurities. An outer layer, 50 to 300 A thick, is rich in many potentially toxic trace elements in the form of simple and complex sulfates. This layer, which is soluble in water, contains essentially all of the particulate sulfur present in fly ash in the form of sulfate. The actual mechanism(s) of formation of particulate sulfate salts a… more
Date: January 1, 1978
Creator: Natusch, D. F.S.
open access

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
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