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Low temperature, sulfur tolerant homogeneous catalysts for the water-gas shift reaction

Description: The purpose of this report is to update and reorganize our recent review on homogeneous catalysis of the water-gas shift reaction (WGSR) based on recent literature publications and patents. This updated version will serve as a means of selecting 10 candidate catalyst systems for use in developing effective, sulfur-tolerant, low temperature WGSR catalysts. This report discusses the variations possible in the basic chemistry associated with WGSR catalytic cycles, including basic, acidic, and neut… more
Date: January 20, 1986
Creator: Laine, R. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of Coupled Chemical and Catalytic Coal Conversion Methods

Description: The objective of this research was to convert coal into a soluble substance under mild conditions. The strategy involved two steps, first to breakdown the macromolecular network of coal, and second to add hydrogen catalytically. We investigated different basic reagents that could, in priciple, break down coal's structure and alkylation strategies that might enhance its solubility. We examined O- and C-alkylation, the importance of the strength of the base, the character of the added alkyl group… more
Date: December 1, 1991
Creator: Stock, L. M.; Chatterjee, K.; Cheng, C.; Ettinger, M.; Flores, F.; Jiralerspong, S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical activation of molecules by metals: Experimental studies of electron distributions and bonding

Description: The formal relationship between measured molecular ionization energies and thermodynamic bond dissociation energies has been developed into a single equation which unifies the treatment of covalent bonds, ionic bonds, and partially ionic bonds. This relationship has been used to clarify the fundamental thermodynamic information relating to metal-hydrogen, metal-alkyl, and metal-metal bond energies. We have been able to obtain a direct observation and measurement of the stabilization energy prov… more
Date: October 1991
Creator: Lichtenberger, Dennis L.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalyst dispersion and activity under conditions of temperature-staged liquefaction

Description: The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of the catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experi… more
Date: February 1, 1992
Creator: Davis, A.; Schobert, H.H.; Mitchell, G.D. & Artok, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Liquefaction of coals using ultra-fine particle, unsupported catalysts: In situ generation by rapid expansion of supercritical fluid solutions

Description: The program objective is to generate ultra-fine catalyst particles (20 to 400 {Angstrom} in size) and quantify their potential for improving coal dissolution in the solubilization stage of two-stage catalytic-catalytic liquefaction systems. It has been shown that catalyst activity increases significantly with decreasing particle size for particle sizes in the submicron range. Ultra-fine catalyst particle generation will be accomplished using a novel two-step process. First, the severe condition… more
Date: August 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solvent Refined Coal (SRC) process: trace elements. Research and development report No. 53, interim report No. 31, August 1976-July 1977. Volume III. Pilot plant development work. Part 6. [Fate of 36 trace elements]

Description: Results are presented on a study of the distribution and fate of 34 trace elements in the Solvent Refined Coal Process at the pilot plant located at Fort Lewis, Washington, and operated by The Pittsburg and Midway Coal Mining Co. under contract with the US Department of Energy. Neutron activation analysis was used to determine Ti, V, Ca, Mg, Al, Cl, Mn, As, Sb, Se, Hg, Br, Co, Ni, Cr, Fe, Na, Rb, Cs, K, Sc, Tb, Eu, Sm, Ce, La, Sr, Ba, Th, Hf, Ta, Ga, Zr, and Cu in feed coals, process solvent, S… more
Date: March 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalyst dispersion and activity under conditions of temperature- staged liquefaction

Description: The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of the catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experi… more
Date: September 1, 1991
Creator: Davis, A.; Schobert, H.H.; Mitchell, G.D. & Artok, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of Coupled Chemical and Catalytic Coal Conversion Methods

Description: When an arene is coordinated to Cr(CO){sub 3}, profound changes in its reactivity occur. Ring and benzylic hydrogen atoms exhibit enhanced acidity, and typical arene reactions such as electrophilic aromatic substitutions are quenched. In contrast, the ring carbon atoms are activated toward attack by nucleophiles. These changes in reactivity are manifestations of the forceful electron withdrawing nature of the Cr(CO){sub 3} component, and of the ability of this group to stabilize charged interme… more
Date: January 1, 1991
Creator: Stock, L. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Catalyst dispersion and activity under conditions of temperature- staged liquefaction

Description: The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experiment… more
Date: February 1, 1992
Creator: Davis, A.; Schobert, H.H.; Mitchell, G.D. & Artok, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(Mechanistic examination of organometallic electron transfer reactions: Annual report, 1989)

Description: Our mechanistic examination of electron transfer reactions between organometallic complexes has required data from our stopped-flow infrared spectrophotometer that was constructed in the first year. Our research on organometallic electron transfer reaction mechanisms was recognized by an invitation to the Symposium on Organometallic Reaction Mechanisms at the National ACS meeting in Miami. We have obtained a reasonable understanding of the electron transfer reactions between metal cations and a… more
Date: January 1, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Carbonyl Emissions from Gasoline and Diesel Motor Vehicles

Description: Carbonyls from gasoline powered light-duty vehicles (LDVs) and heavy-duty diesel powered vehicles (HDDVs) operated on chassis dynamometers were measured using an annular denuder-quartz filter-polyurethane foam sampler with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine derivatization and chromatography-mass spectrometry analyses. Two internal standards were utilized based on carbonyl recovery, 4-fluorobenzaldehyde for<C8 carbonyls and 6-fluoro-4-chromanone for>_C8 compounds. Gas- and partic… more
Date: December 1, 2007
Creator: Destaillats, Hugo; Jakober, Chris A.; Robert, Michael A.; Riddle, Sarah G.; Destaillats, Hugo; Charles, M. Judith et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characterization of selective binding of alkali cations with carboxylate by x-ray absorption spectroscopy of liquid microjets

Description: We describe an approach for characterizing selective binding between oppositely charged ionic functional groups under biologically relevant conditions. Relative shifts in K-shell x-ray absorption spectra of aqueous cations and carboxylate anions indicate the corresponding binding strengths via perturbations of carbonyl antibonding orbitals. XAS spectra measured for aqueous formate and acetate solutions containing lithium, sodium, and potassium cations reveal monotonically stronger binding of th… more
Date: January 8, 2008
Creator: Saykally, Richard J; Uejio, Janel S.; Schwartz, Craig P.; Duffin, Andrew M.; Drisdell, Walter S.; Cohen, Ronald C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studies relevant to the catalytic activation of carbon monoxide

Description: Research activity has included continued mechanistic investigations of the nucleophilic activation of carbon monoxide such as homogeneous catalysis of the water gas shift and key steps in the relevant catalytic cycles. Other investigations of related processes included the application of fast reaction techniques to prepare and to investigate quantitatively reactive organometallic intermediates relevant to the activation of hydrocarbons toward carbonylation and other functionalizations. 8 refs.
Date: September 4, 1991
Creator: Ford, P.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(Comparison of group transfer, inner shere and outer sphere electron transfer mechanisms for organometallic complexes)

Description: Our studies of reactions of metal carbonyl cations and anions have shown that metal carbonyl cations can catalyze CO exchange reactions on metal carbonyl anions. This result provides further evidence for a mechanism involving attack of the metal carbonyl anion on a carbon of the metal carbonyl cation in CO{sup 2+} transfer reactions. Reaction of metal carbonyl anions with metal carbonyl halides is a common approach to formation of metal-metal bonds. We have begun to use kinetic data and product… more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanistic studies of carbon monoxide reduction

Description: The progress made during the current grant period (1 January 1988--1 April 1990) in three different areas of research is summarized. The research areas are: (1) oxidatively-induced double carbonylation reactions to form {alpha}-ketoacyl complexes and studies of the reactivity of the resulting compounds, (2) mechanistic studies of the carbonylation of nitroaromatics to form isocyanates, carbamates, and ureas, and (3) studies of the formation and reactivity of unusual metallacycles and alkylidene… more
Date: June 12, 1990
Creator: Geoffroy, G.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation and photochemistry section

Description: The highlights of this past year in the Radiation and Photochemistry Section at Argonne include: (1) picosecond optical studies of radical cations and excited states produced in hydrocarbon radiolysis provided the first kinetic measurements of ion transformation and production of triplet and singlet excited states by ion recombination. (2) studies of radical cations of alkyl-substituted amines and sulfides provided insights into ion-molecule reactions of radical cations in the condensed phase. … more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(Comparison of group transfer, inner sphere and outer sphere electron transfer mechanisms of organometallic complexes)

Description: During the course of Grant ER13775 we have constructed an infrared stopped-flow spectrophotometer and initiated a study of the mechanisms of reactions that involve a change in the oxidation state of organometallic complexes. The spectrometer combined conventional stopped-flow techniques with an infrared optical system comprised of a carbon monoxide laser, an IRTRAN flow-through cell and a mercury-cadium-telluride detector. In this summary we will highlight our results on reactions: (1) that for… more
Date: January 1, 1990
Creator: Atwood, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CVD techniques applied to energy problems

Description: Some of the applications of chemical vapor deposition in energy related programs will be discussed, and coating parameters will be described. The coatings to be discussed were made at reduced pressures from the hydrogen reduction of metal fluorides, or metal silane and from the pyrolysis of metal carbonyls.
Date: January 1, 1981
Creator: McCreary, W.J. & Carroll, D.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemical interactions in multimetal/zeolite catalysts

Description: Mechanistic explanations have been found for the migration of atoms and ions through the zeolite channels leading to specific distribution of ions and the metal clusters. In this report, we summarize the state of understanding attained on a number of topics in the area of mono- and multimetal/zeolite systems, to which our recent research has made significant contributions. The following topics are discussed: (1) Formation of isolated metal atoms in sodalite cages; (2) differences of metal/zeoli… more
Date: February 7, 1992
Creator: Sachtler, W.M.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Organometallic chemistry of bimetallic compounds

Description: This report consists of six sections: heterobimetallic dihydrides, early-late transition metal heterobimetallic compounds, amphiphilic carbene complexes and hydroxycarbene complexes, diiron compounds with bridging hydrocarbon ligands, diphosphine chelates with natural bite angles near 120 degrees, and synthesis and reactions of M=M compounds. (WET)
Date: July 1, 1991
Creator: Casey, C. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Bioconversion of coal-derived synthesis gas to liquid fuels. [Butyribacterium methylotrophicum]

Description: The use of coal-derived synthesis gas as an industrial feedstock for production of fuels and chemicals has become an increasingly attractive alternative to present petroleum-based chemicals production. However, one of the major limitations in developing such a process is the required removal of catalyst poisons such as hydrogen sulfide (H{sub 2}S), carbonyl sulfide (COS), and other trace contaminants from the synthesis gas. Purification steps necessary to remove these are energy intensive and a… more
Date: January 1, 1991
Creator: Jain, M. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An analysis of the effect of system variables on the quality of thin films and powders produced by laser-breakdown chemical vapor deposition

Description: A gas phase process for large area depositions on an ambient temperature substrate using laser-induced dielectric breakdown of gas phase precursors has recently been developed. Deposits of nickel alloys show excellent grain refinement (<10 nm) and metastable phase incorporation due to rapid quenching from the gas phase. Particle size distribution and compositional variance within the deposited films have been studied using electron microscopy and electron diffraction. Kinetic expressions to exp… more
Date: January 1, 1987
Creator: Joyce, E.L. Jr. & Jervis, T.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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