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Diffusion of Slow Electrons in Gases

Description: The properties of electrons in a gas and an external electric field, e.g., agitation velocity, free path, energy lost per collision, and collision cross sections, were determined for electrons of energy less than 2 ev in a large number of gases. The computations were made from previously measured values for Townsend's energy factor or the ratio of electron agitation energy to molecule thermal energy. Results are presented for hydrogen, nitrogen, carbon dioxide, methane, ethylene, cyclopropane, … more
Date: October 24, 1961
Creator: Forester, D. W. & Cochran, L. W.
Partner: UNT Libraries Government Documents Department
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H-Area Seepage Basins

Description: During the third quarter of 1990 the wells which make up the H-Area Seepage Basins (H-HWMF) monitoring network were sampled. Laboratory analyses were performed to measure levels of hazardous constituents, indicator parameters, tritium, nonvolatile beta, and gross alpha. A Gas Chromatograph Mass Spectrometer (GCMS) scan was performed on all wells sampled to determine any hazardous organic constituents present in the groundwater. The primary contaminants observed at wells monitoring the H-Area Se… more
Date: December 1, 1990
Creator: Stejskal, G.
Partner: UNT Libraries Government Documents Department
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Diagnosing vegetation injury caused by air pollution

Description: The structure and function of plants in relation to air pollution injury is discussed. The sources, atmospheric chemistry, monitoring data, symptomatology, factors affecting plant response, injury threshold doses, air quality standards, relative sensitivity of plants, and leaf tissue analysis are discussed for major air pollutants. Among the pollutants discussed are: the photochemical oxidants (ozone, PAN, nitrogen oxides, sulfur dioxide, and fluorides). Minor pollutants discussed in the same f… more
Date: February 1, 1978
Partner: UNT Libraries Government Documents Department
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HC quench layer formation in combustion processes. Technical progress report, January-April 1980

Description: The project is aimed at understanding wall quenching and other processes responsible for surface generated hydrocarbons in combustion under engine-like conditions. The study concerns the effects of turbulence on the evolution of hydrocarbons. At the conclusion of the program, significant new experimental information will have been generated and an analytical model of the fluid mechanics and some aspects of the chemistry of quenching will be formulated. The work is divided into three tasks: (1) … more
Date: June 1, 1980
Creator: Lavoie, G. A.
Partner: UNT Libraries Government Documents Department
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Research into the pyrolysis of pure cellulose, lignin, and birch wood flour in the China Lake entrained-flow reactor

Description: This experimental program used the China Lake entrained-flow pyrolysis reactor to briefly investigate the pyrolysis of pure cellulose, pure lignin, and birch wood flour. The study determined that the cellulose and wood flour do pyrolyze to produce primarily gaseous products containing significant amounts of ethylene and other useful hydrocarbons. During attempts to pyrolyze powdered lignin, the material melted and bubbled to block the reactor entrance. The pure cellulose and wood flour produced… more
Date: June 1, 1980
Creator: Diebold, J.
Partner: UNT Libraries Government Documents Department
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Interdisciplinary research and training program in the plant sciences

Description: This document is the compiled progress reports from the Interdisciplinary Research and Training Program in the Plant Sciences funded through the MSU-DOE Plant Research Laboratory. Fourteen reports are included, covering topics such as the molecular basis of plant/microbe symbiosis, cell wall proteins and assembly, gene expression, stress responses, growth regulator biosynthesis, interaction between nuclear and organelle genomes, sensory transduction and tropisms, intracellular sorting and membr… more
Date: January 1, 1991
Creator: Wolk, C.P.
Partner: UNT Libraries Government Documents Department
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High-efficiency photoionization detector

Description: A high efficiency photoionization detector using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36 +- 0.02 eV, and a vapor pr… more
Date: May 12, 1981
Creator: Anderson, D.F.
Partner: UNT Libraries Government Documents Department
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Combustion Research Program: Flame studies, laser diagnostics, and chemical kinetics

Description: We have made a detailed study of the care that must be taken to correctly measure OH radical concentrations in flames. A large part of these studies has concerned collisional quenching of hydride radical species (OH, NH, and NH{sub 2}), in particular the dependence upon rotational level and collision velocity (temperature). The results on OH and NH have shown unique and interesting behavior from the viewpoint of fundamental molecular dynamics, pointing to quenching often governed by collisions … more
Date: January 22, 1991
Creator: Crosley, D.R.
Partner: UNT Libraries Government Documents Department
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Catalyst and Feedstock Effects in the Thermochemical Conversion of Biomass to Liquid Transportation Fuels

Description: The thermochemical conversion of biomass feedstocks to liquid transportation fuels can be accomplished by three processes, namely gasification, high-pressure liquefaction, and pyrolysis. In this study, the pyrolysis option is selected which is followed by the catalytic upgrading of pyrolysis vapors to aromatic and olefinic hydrocarbons (PYROCAT process). The aromatics constitute a high-octane gasoline blend, while the olefins can be utilized as feedstocks for various chemicals. The PYROCAT proc… more
Date: May 1992
Creator: Rejai, B.; Agblevor, F. A.; Evans, R. J. & Wang, D.
Partner: UNT Libraries Government Documents Department
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Isotope effect on the zero point energy shift upon condensation

Description: The various isotope-dependent and independent atomic and molecular properties that pertain to the isotopic difference between the zero point energy (ZPE) shifts upon condensation were derived. The theoretical development of the change of the ZPE associated with the internal molecular vibrations, due to the condensation of the gaseous molecules, is presented on the basis of Wolfsberg's second-order perturbation treatment of the isotope-dependent London dispersion forces between liquid molecules.… more
Date: July 1, 1977
Creator: Kornblum, Z.C. & Ishida, T.
Partner: UNT Libraries Government Documents Department
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Synthesis gas solubility in Fischer-Tropsch slurry: Final report

Description: The objective is to investigate the phase equilibrium behavior of synthesis gases and products in a Fischer-Tropsch slurry reactor. A semi-flow apparatus has been designed and constructed for this purpose. Measurements have been made for hydrogen, cabon monoxide, methane, ethane, ethylene, and carbon dioxide in a heavy n-paraffin at temperatures from 100 to 300)degree)C and pressures 10 to 50 atm. Three n-paraffin waxes: n-eicosane (n-C/sub 20/), n-octacosane )n-C/sub 28/), and n-hexatriacontan… more
Date: January 1, 1988
Creator: Chao, K.C. & Lin, H.M.
Partner: UNT Libraries Government Documents Department
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Oxygen/steam gasification of wood

Description: Yields from fixed-bed gasification of stoker fuel, pressed planar shavings, are presented for air/steam operation and oxygen/steam operation at four different compositions. The wood carbon distributes between gas products and liquid products in the respective ranges of 75 to 80 wt% and 20 to 25 wt%. The cold gas efficiencies, defined as the combustible energy in the gas divided by the heat of combustion of the wood, were 60% for operation with an air-to-steam weight ratio of 10, 52%, 61%, 59%, … more
Date: April 1, 1980
Creator: Mudge, L.K.; Ham, D.G.; Weber, S.L. & Mitchell, D.H.
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
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Combustion-turbulence interaction in the turbulent boundary layer over a hot surface

Description: The turbulence-combustion interaction in a reacting turbulent boundary layer over a heated flat plate was studied. Ethylene/air mixture with equivalence ratio of 0.35 was used. The free stream velocity was 10.5 m/s and the wall temperature was 1250/sup 0/K. Combustion structures visualization was provided by high-speed schlieren photographs. Fluid density statistics were deduced from Rayleigh scattering intensity measurements. A single-component laser Doppler velocimetry system was used to obta… more
Date: January 1, 1982
Creator: Ng, T.T.; Cheng, R.K.; Robben, F. & Talbot, L.
Partner: UNT Libraries Government Documents Department
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Site Characterization Program at the Radioactive Waste Management Complex of the Idaho National Engineering Laboratory

Description: The Radioactive Waste Management Complex (RWMC) Site Characterization Program is a continuation of the Subsurface Investigation Program (SIP). The scope of the SIP has broadened in response to the results of past work that identified hazardous as well as radionuclide contaminants in the subsurface environment and in response to the need to meet regulatory requirements. Two deep boreholes were cored at the RWMC during FY-1988. Selected sediment samples were submitted for Appendix IX of 40 CFR Pa… more
Date: July 1, 1989
Creator: McElroy, D. L.; Rawson, S. A.; Hubbell, J. M.; Minkin, S. C.; Baca, R. G.; Vigil, M. J. et al.
Partner: UNT Libraries Government Documents Department
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Polyketones and polysulfones for conservation in the ethylene polymer industry. Progress report No. 6, July-September 1979

Description: The characterization study on ethylene-CO (Et-CO) copolymers was concluded. The copolymers were prepared at various levels of CO composition, and with several methods loss of catalysis, including free-radical, metallic, and /sup 60/Co irradiation. Et-CO copolymers exhibit crystallinity related to the alternating polyketone structure which increasees logarithmically with CO content over the range 28% to 49% CO. The melting point increases in essentially the same manner as crystallinity. The stru… more
Date: January 1, 1980
Creator: Steinberg, M.; Johnson, R.; Elling, D.; Cordes, W. & Goodman, D.
Partner: UNT Libraries Government Documents Department
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Infrared analysis of coal gasifier product gases

Description: Infrared absorption measurements using a Fourier transform infrared spectrometer have been found to be a convenient way to measure the concentration of certain infrared-absorbing gases always present in a coal gasifier product stream. In this paper, we describe preliminary measurements using this technique with gas mixtures representative of gasifier products in high pressure, statically filled cells. No attempt was made at this point to simulate the actual gasifier environment vis-a-vis antici… more
Date: January 1, 1980
Creator: Holland, R.F.; Quigley, G.P. & Vasquez, M.C.
Partner: UNT Libraries Government Documents Department
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Silver ion mediated shape control of platinum nanoparticles: Removal of silver by selective etching leads to increased catalytic activity

Description: A procedure has been developed for the selective etching of Ag from Pt nanoparticles of well-defined shape, resulting in the formation of elementally-pure Pt cubes, cuboctahedra, or octahedra, with a largest vertex-to-vertex distance of {approx}9.5 nm from Ag-modified Pt nanoparticles. A nitric acid etching process was applied Pt nanoparticles supported on mesoporous silica, as well as nanoparticles dispersed in aqueous solution. The characterization of the silica-supported particles by XRD, TE… more
Date: January 9, 2008
Creator: Grass, Michael E.; Yue, Yao; Habas, Susan E.; Rioux, Robert M.; Teall, Chelsea I. & Somorjai, G.A.
Partner: UNT Libraries Government Documents Department
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TRITIUM EFFECTS ON DYNAMIC MECHANICAL PROPERTIES OF POLYMERIC MATERIALS

Description: Dynamic mechanical analysis has been used to characterize the effects of tritium gas (initially 1 atm. pressure, ambient temperature) exposure over times up to 2.3 years on several thermoplastics-ultrahigh molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE), and Vespel{reg_sign} polyimide, and on several formulations of elastomers based on ethylene propylene diene monomer (EPDM). Tritium exposure stiffened the elastic modulus of UHMW-PE up to about 1 year and then softened i… more
Date: November 12, 2008
Creator: Clark, E
Partner: UNT Libraries Government Documents Department
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Chemical-kinetic prediction of critical parameters in gaseous detonations

Description: A theoretical model including a detailed chemical kinetic reaction mechanism for hydrogen and hydrocarbon oxidation is used to examine the effects of variations in initial pressure and temperature on the detonation properties of gaseous fuel-oxidizer mixtures. Fuels considered include hydrogen, methane, ethane, ethylene, and acetylene. Induction lengths are computed for initial pressures between 0.1 and 10.0 atmospheres and initial temperatures between 200K and 500K. These induction lengths are… more
Date: January 12, 1982
Creator: Westbrook, C.K. & Urtiew, P.A.
Partner: UNT Libraries Government Documents Department
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Surface science study of selective ethylene epoxidation catalyzed by the Ag(110) surface: structural sensitivity

Description: The selective oxidation of ethylene to ethylene epoxide (C/sub 2/H/sub 4/ + 1/2 O/sub 2/ ..-->.. C/sub 2/H/sub 4/O) over Ag is the simplest example of kinetically-controlled, selective heterogeneous catalysis. We have studied the steady-state kinetics and selectivity of this reaction for the first time on a clean, well-characterized Ag(110) surface by using a special apparatus which allows rapid (approx. 20 s) transfer between a high-pressure catalytic microreactor and an ultrahigh vacuum surfa… more
Date: January 1, 1983
Creator: Campbell, C.T.
Partner: UNT Libraries Government Documents Department
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TMVOC-MP: a parallel numerical simulator for Three-PhaseNon-isothermal Flows of Multicomponent Hydrocarbon Mixtures inporous/fractured media

Description: TMVOC-MP is a massively parallel version of the TMVOC code (Pruess and Battistelli, 2002), a numerical simulator for three-phase non-isothermal flow of water, gas, and a multicomponent mixture of volatile organic chemicals (VOCs) in multidimensional heterogeneous porous/fractured media. TMVOC-MP was developed by introducing massively parallel computing techniques into TMVOC. It retains the physical process model of TMVOC, designed for applications to contamination problems that involve hydrocar… more
Date: February 15, 2008
Creator: Zhang, Keni; Yamamoto, Hajime & Pruess, Karsten
Partner: UNT Libraries Government Documents Department
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