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Time-Resolved Infrared Absorption Studies Applied to the Study of Radical Plus Molecule Reactions

Description: Reaction of the cyano radical (CN) with ethane (C{sub 2}H{sub 6}) was studied using time resolved infrared absorption to monitor the product hydrogen cyanide (HCN) in individual to-vibrational states. Pulse laser photolysis was used to provide an initial excess of the CN radical and the time dependence of individual ro-vibrational states of the high frequency anti-symmetric stretching mode of HCN (0,0,v{sub 3}) was followed. These experiments reveal that the initial product state distribution o… more
Date: February 1, 1994
Creator: Bethardy, G. A.; Macdonald, R. G. & Northrup, F. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Catalytic conversion of light alkanes. Final report, January 1, 1990--October 31, 1994

Description: During the course of the first three years of the Cooperative Agreement (Phase I-III), we uncovered a family of metal perhaloporphyrin complexes which had unprecedented activity for the selective air-oxidation of fight alkanes to alcohols. The reactivity of fight hydrocarbon substrates with air or oxygen was in the order: isobutane>propane>ethane>methane, in accord with their homolytic bond dissociation energies. Isobutane was so reactive that the proof-of concept stage of a process for produci… more
Date: December 31, 1998
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Structure-property relationships of BaCeO perovskites for the oxidative dehydrogenation of alkanes

Description: The oxidative dehydrogenation (ODH) reactions for the formation of two important organic feedstocks ethylene and propylene are of great interest because of the potential in capital and energy savings associated with these reactions. Theoretically, ODH can achieve high conversions of the starting materials (ethane and propane) at lower temperatures than conventional dehydrogenation reactions. The important focus in this study of ODH catalysts is the development of a structure-property relationsh… more
Date: December 1, 1997
Creator: Nenoff, T. M.; Jackson, N. B.; Miller, J. E.; Sault, A. G. & Trudell, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The rate-limiting step for alkane dehydrogenation in zeolite H-ZSM-5.

Description: We have carried out a computational study of protolytic cracking, dehydrogenation, and H/D exchange of ethane, propane, and butane using a cluster model of H-ZSM-5. Our previous work has demonstrated that quantum-chemical techniques can give quantitatively accurate activation energies for alkane cracking in zeolites [1]. Experimental kinetic studies have shown that the apparent activation energies for cracking and H/D exchange decrease with n-alkane chain length, while for dehydrogenation the e… more
Date: November 1, 2000
Creator: Zygmunt, S. A.; Bootz, B. L.; Miller, A. W.; Curtiss, L. A. & Iton, L. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Supercritical thermodynamics of sulfur and nitrogen species. Quarterly progress report, January 1, 1994--March 31, 1994

Description: Significant opportunity exists for the application of supercritical fluid (SCF) technology to coal processing, both for pretreatment of high sulfur coals, as well as liquefaction and treatment of coal liquids. Supercritical fluids are attractive solvents for a variety of coal processing applications because of their unusual solvating and mass transfer properties. Solubility studies have been carried out for a number of model coal and coal-liquid compounds, primarily in pure supercritical fluids… more
Date: June 1, 1994
Creator: Eckert, C. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Superacid catalysis of light hydrocarbon conversion. Eleventh quarterly report, April 1, 1996--June 30, 1996

Description: The new catalyst Fe- and Mn-promoted sulfated zirconia is remarkably active for the low-temperature (even room temperature) isomerization of n-butane to give isobutane in the near absence of side products. Thus this catalyst offers excellent potential for practical application in this process. The catalyst is so active that it even converts smaller alkanes, including propane and ethane. The ethane conversion is orders of magnitude slower than the butane conversion, and the prospects for practic… more
Date: December 31, 1996
Creator: Gates, B. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alkaline dechlorination of chlorinated volatile organic compounds

Description: The vast majority of contaminated sites in the United States and abroad are contaminated with chlorinated volatile organic compounds (VOCs) such as trichloroethylene (TCE), trichloroethane (TCA), and chloroform. These VOCs are mobile and persistent in the subsurface and present serious health risks at trace concentrations. The goal of this project was to develop a new chemical treatment system that can rapidly and effectively degrade chlorinated VOCs. The system is based on our preliminary find… more
Date: June 1, 1996
Creator: Gu, Baohua & Siegrist, Robert L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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SANS study of dialkylsubstituted diphosphonic acids and their complexes with Ca, Fe, La, Th and U in toluene

Description: The aggregation of di(2ethylhexyl) methane-, ethane- and butanediphosphonic acids and their complexes with various metal cations at different concentrations in toluene has been studied in detail using Small Angle Neutron Scattering. The diphosphonic acids are being employed as novel solvent extraction reagents in the Chemistry Division of ANL. These compounds exhibit extraordinarily strong affinity for actinide ions and for Fe(III). The growth of large metal-diphosphonate aggregates depends on … more
Date: July 21, 1997
Creator: Urban, V.; Ku, C.Y. & Thiyagarajan, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling of on-line catalyst addition effects in a short contact time reactor

Description: Recently developed short-contact-time reactors (SCTR), consisting of porous alumina monoliths coated with platinum, have been shown to produce ethylene from rich ethane/oxygen(hydrogen) mixtures with yields and selectivities comparable to conventional steam cracking, using a reactor of much smaller size. Although the overall mechanism is clearly autothermal and catalytic, the details, in particular the relative contributions of heterogeneous and homogeneous chemistry, are a matter of considerab… more
Date: July 30, 2000
Creator: Zerkle, D. K.; Allendorf, M. d.; Wolf, M. & Deutschmann, O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fluid-Rock Characterization and Interactions in NMR Well Logging

Description: This semi-annual report briefly summarizes the progress since the 1st Annual Report issued September, 2000 and the next annual report. More detailed results will be in the annual reports. The main emphasis on fluid properties was on measurements of the relaxation time and self-diffusion coefficient of ethane and propane. Ethane is similar to methane while propane is more similar to the higher alkanes. The ratio of T1 and T2 is demonstrated to be a function of both viscosity and the NMR frequenc… more
Date: July 13, 2001
Creator: Hirasaki, George J. & Mohanty, Kishore K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Superacid catalysis of light hydrocarbon conversion. DOE PETC seventh quarterly progress report, April 1, 1995--July 31, 1995

Description: Iron- and manganese-promoted sulfated zirconia is a catalyst for the conversion of propane, but the rate of conversion of propane is much less than the rate of conversion of butane. Whereas this catalyst appears to be a good candidate for practical, industrial conversion of butane, it appears to lack sufficient activity for practical conversion of propane. The propane conversion data reported here provide excellent insights into the chemistry of the catalytic conversion. Solid and catalysts, na… more
Date: February 1, 1996
Creator: Gates, B. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Supercritical thermodynamics of sulfur and nitrogen species. Quarterly progress report, October 1, 1992--December 31, 1992

Description: Significant opportunity exists for the application of supercritical fluid.(SCF) technology to coal processing, both for pretreatment of high sulfur coals, as well as liquefaction and treatment of coal liquids. Supercritical fluids are attractive solvents for a variety of coal processing applications because of their unusual solvating and mass transfer properties. Solubility studies have been carried out for a number of model coal and coal-liquid compounds, primarily in pure supercritical fluids… more
Date: October 1, 1991
Creator: Eckert, C. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sequestering Carbon Dioxide in Coalbeds

Description: During the present reporting period, six complementary tasks involving experimentation, model development, and coal characterization were undertaken to meet our project objectives: (1) A second adsorption apparatus, utilizing equipment donated by BP Amoco, was assembled. Having confirmed the reliability of this additional experimental apparatus and procedures, adsorption isotherms for CO{sub 2}, methane, ethane, and nitrogen on wet Fruitland coal and on activated carbon were measured at 319.3 K… more
Date: June 15, 2001
Creator: Gasem, K. A. M.; Robinson, R. L., Jr. & Radovic, L. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Adsorption and Surface Reactions of Hydrocarbons on Clean Iridium

Description: The adsorption of ethane, ethylene, and acetylene on clean iridium in a field emission microscope was found to cause characteristic changes in the work function of the iridium surface. Further changes, which were time and temperature dependent, resulted when such surfaces were heated. Flash filament experiments showed that the changes in work function upon henting are due to desorption reactions and that the desorbed product consists principally of hydrogen. By assuming a linear relationship be… more
Date: April 1, 1962
Creator: Arthur, J. R., Jr. & Hanson, R. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transition Metal Catalyzed Hydroarylation of Multiple Bonds: Exploration of Second Generation Ruthenium Catalysts and Extension to Copper Systems

Description: Catalysts provide foundational technology for the development of new materials and can enhance the efficiency of routes to known materials. New catalyst technologies offer the possibility of reducing energy and raw material consumption as well as enabling chemical processes with a lower environmental impact. The rising demand and expense of fossil resources has strained national and global economies and has increased the importance of accessing more efficient catalytic processes for the convers… more
Date: February 17, 2011
Creator: Gunnoe, T. Brent
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Novel process for depolymerization of coal to C{sub 2}-C{sub 4} hydrocarbons. Final report, 1 September 1989--31 August 1993

Description: A principal objective of this work was to study the conversion of coal to C{sub 2} {minus} C{sub 4} hydrocarbons in a two-stage reactor system. Coal was converted to liquids at 440{degrees}C in a stirred batch autoclave using tetralin as the hydrogen donor solvent. The liquids produced were separated from the unreacted coal and ash by filtration. The liquids were then fed into a second stage fixed bed reactor containing sulfided Ni-Mo/Al{sub 2}O{sub 3} and SiO{sub 2{minus}}Al{sub 2}O{sub 3} cat… more
Date: July 8, 1994
Creator: Wiser, W. H. & Oblad, A. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microstrip gas chamber on thin-film Pestov glass and micro gap chamber

Description: The authors report developments of the Microstrip Gas Chamber on thin-film Pestov glass and the Micro Gap Chamber. By coating a thin-layer of low-resistive, electronically-conductive glass on various substrates (including quartz and ceramics), they built MSGCs of high gain stability and low leakage current. They were tested in Ar-CH{sub 4} (10%) and He-C{sub 2}H{sub 6} (50%) gas mixtures. Energy resolutions of 17-20% were measured for 6keV x-rays. This design can make the choice of substrate le… more
Date: July 1, 1994
Creator: Gong, W. G.; Harris, J. W. & Wieman, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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HYDROLYSIS OF URANIUM CARBIDES BETWEEN 25 AND 100 . II. AS-CAST ALLOYS CONTAINING 2 TO 10 WT % CARBON

Description: Reactions with water of as-cast uranium-carbon alloys containing 2to 10 wt% carbon (UC/sub 0.4/ to UC/sub 2.2/) were investigated by using gas- chromatography for analysis of the gaseous products. Uranium metal-uranium monocarbide alloys yielded 2 moles of free hydrogen per mole of free metal, in addition to methane, small quantities of higher molecular weight gaseous hydrocarbons, and a solid, hydrous, tetravalent uranium oxide. The gaseous producte contained all the carbon originally present … more
Date: January 21, 1963
Creator: Bradley, M.J. & Ferris, L.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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THE REACTIONS OF ENERGETIC CARBON ATOMS IN METHANE OXYGEN AND PHASE DEPENDENCE RADIATION DAMAGE EFFECTS

Description: Studies were made on the reactions of C/sup 11/ in methane containing oxygen. The nuclear reactions C/sup 12/(n,2n) and C/sup 12/(p,pn) were used to produce C/sup 11/. Concomitant radiolysis of the methane during C/sup 11/ production clearly affected product distribution. C/sup 11/-labeled ethane and propane decreased while methane, ethylene, and acetylene decreased. It was assumed that reduction by hydrogen atoms was probably occurring in the unscavenged system. The effects of oxygen and of ph… more
Date: August 1, 1963
Creator: Stoecklin, G.; Stangl, H.; Christman, D. R.; Cumming, J. B. & Wolf, A. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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