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Probe molecule studies: Active species in alcohol synthesis

Description: The goal of this research is to develop a better understanding of the mechanisms of formation of alcohols and other oxygenates from syngas over supported catalysts. Probe molecules will be added in situ during the reaction to help delineate reaction pathways and identify reaction intermediate species. The key of our study is to investigate how the species generated by these probe molecules interact with surface species present during oxygenate formation.
Date: April 1, 1992
Creator: Blackmond, D.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nuclear medicine program progress report for quarter ending December 31, 1991

Description: This report presents information on (1) a new improved synthesis of carrier-free rhenium-188-labeled Re(V) dimercaptosuccinic acid (DMSA) complex as a potential therapeutic agent for treatment of thyroid medullary carcinoma; and (2) the synthesis and evaluation of a series of iodine-125-labeled analogues of altanserine for imaging of serotonin receptors.
Date: April 1, 1992
Creator: Knapp, F. F., Jr.; Ambrose, K. R.; Callahan, A. P.; McPherson, D. W.; Mirzadeh, S.; Srivastava, P. C. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A novel process for methanol synthesis

Description: A bench-scale reactor is being used to study the conversion of synthesis gas to methanol (MeOH) by a novel process. In previous reports, we provided evidence that the reaction takes place in two steps. A molecule of MeOH is first carbonylated to form methyl formate (MeF) which then reacts with H{sub 2} to form two molecules of MeOH. The second reaction occurs on the surface of a heterogeneous catalyst such as copper chromite, while the first reaction requires a homegenous catalyst such as potas… more
Date: January 1, 1992
Creator: Tierney, J.W. & Wender, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Probing flame chemistry with MBMS, theory, and modeling

Description: The program objective is to establish kinetics of combustion and molecular weight growth in C{sub 3} hydrocarbon flames as part of an ongoing study of flame chemistry. Specific reactions to be studies are (1) the oxidation reactions of O and OH with C{sub 3}'s and (2) the growth reactions of C{sub 3}H{sub 5} and C{sub 3}H{sub 3} with themselves and with unsaturated hydrocarbons. Our approach combines molecular-beam mass spectroscopy (MBMS) experiments which give concentrations of stable species… more
Date: March 1, 1992
Creator: Westmoreland, P.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fundamental studies of catalytic processing of synthetic liquids

Description: This project revolves around understanding the fundamental processes involved in the catalytic removal of harmful oxygenated organics present in coal liquids. We are modelling the complex type of sulfided Mo catalyst proposed for these reactions with simple single crystal surfaces. These display a controlled range and number of reaction sites and can be extensively characterized by surface science techniques. We then investigate the reaction pathways for representative simple oxygenates upon th… more
Date: January 22, 1992
Creator: Watson, P. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Inhibition of moist carbon monoxide oxidation by trace amounts of hydrocarbons

Description: The moist carbon monoxide oxidation reaction perturbed by small quantities of hydrocarbons is studied over the temperature range 1026--1140 K at 1 atm to yield information on the reactions of OH, H, and O radicals with hydrocarbons (RH) and on general mechanistic inhibition behavior. The inhibiting action of hydrocarbons below the second explosion limit of Co/H{sub 2}O/O{sub 2} mixtures is used for obtaining rate parameters for RH + OH in the case of methane and propene. Considering all the hyd… more
Date: January 1, 1992
Creator: Yetter, R.A. & Dryer, F.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A novel process for methanol synthesis. [Concurrent sythesis of methly formate and methanol]

Description: A bench-scale reactor is being used to conduct studies of the conversion of synthesis gas to methanol (MeOH) by a novel process. In previous reports, we provided evidence for a two-step reaction in series, the carbonylation reaction taking place mainly in a non-equilibrium region in the vicinity of the copper chromite surface, and the hydrogenolysis reaction taking place on the surface of the copper chromite. Interaction between the two catalysts enhances the rate of methanol formation. In this… more
Date: January 1, 1992
Creator: Tierney, J.W. & Wender, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Studies Relevant to the Catalytic Activation of Carbon Monoxide

Description: Research activity during the 1991--1992 funding period has been concerned with the following topics relevant to carbon monoxide activation. (1) Exploratory studies of water gas shift catalysts heterogenized on polystyrene based polymers. (2) Mechanistic investigation of the nucleophilic activation of CO in metal carbonyl clusters. (3) Application of fast reaction techniques to prepare and to investigate reactive organometallic intermediates relevant to the activation of hydrocarbons toward carb… more
Date: June 4, 1992
Creator: Ford, P. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

(Ligand intermediates in metal-catalyzed reactions)

Description: This report consists of sections on sigma bond complexes of alkenes, a new carbon-hydrogen bond activation reaction of alkene complexes, carbon-hydrogen bond migrations in alkylidene complexes, carbon- hydrogen bond migrations in alkyne complexes, synthesis, structure and reactivity of C{sub x} complexes, synthesis and reactivity of alcohol and ether complexes, new catalysts for the epimerization of secondary alcohols; carbon-hydrogen bond activation in alkoxide complexes, pi/sigma equilibria i… more
Date: January 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Semiconductor electrochemistry of coal pyrite

Description: Pyrite synthesis is of interest in many diverse fields, such as geology, fuel processing technology, chemistry, metallurgy, materials science, and so on. Based on fundamental studies of this process, the formation mechanisms of this important sulfide on the earth can be better understood. The studies can also help us to better understand the surface chemistry and electrochemistry of pyrite, thereby assisting in the development of more efficient processes for removal of the sulfide from coal. Th… more
Date: January 1, 1992
Creator: Osseo-Asare, K. & Wei, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Semiconductor electrochemistry of coal pyrite

Description: The kinetics of the formation of Fe(HS)[sup 2]-n[sub n,] the intermediate in the formation of FeS (from the reaction between aqueous sulfide ions and dissolved FE(II) salts) was studied with a stopped-flow spectrophotometric technique. As described in the previous report, the absorbance-time curve indicated that a black substance formed within the first few seconds of the reaction; this material subsequently decomposed gradually to give a lighter dark product within the following several minute… more
Date: January 1, 1992
Creator: Osseo-Asare, K. & Wei, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Inhibition of moist carbon monoxide oxidation by trace amounts of hydrocarbons

Description: The moist carbon monoxide oxidation reaction perturbed by small quantities of hydrocarbons is studied over the temperature range 1026--1140 K at 1 atm to yield information on the reactions of OH, H, and O radicals with hydrocarbons (RH) and on general mechanistic inhibition behavior. The inhibiting action of hydrocarbons below the second explosion limit of Co/H{sub 2}O/O{sub 2} mixtures is used for obtaining rate parameters for RH + OH in the case of methane and propene. Considering all the hyd… more
Date: March 1, 1992
Creator: Yetter, R. A. & Dryer, F. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Semiconductor electrochemistry of coal pyrite. Technical progress report, July--September 1992

Description: The kinetics of the formation of Fe(HS){sup 2}-n{sub n,} the intermediate in the formation of FeS (from the reaction between aqueous sulfide ions and dissolved FE(II) salts) was studied with a stopped-flow spectrophotometric technique. As described in the previous report, the absorbance-time curve indicated that a black substance formed within the first few seconds of the reaction; this material subsequently decomposed gradually to give a lighter dark product within the following several minute… more
Date: December 31, 1992
Creator: Osseo-Asare, K. & Wei, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Radiation and Photochemistry Section annual report, October 1991--September 1992

Description: A survey is presented of research on reactive intermediates in the condensed phase and chemistry induced by energetic radiation. The survey is presented in two major parts: (1) ions, excited states, and other transients in condensed phase; and (2) role of solvents in chemical reactivity. Accelerator activities (20-MeV linac, 3-MeV Van de Graaff) are summarized.
Date: November 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Early events following radiolytic and photogeneration of radical cations in hydrocarbons

Description: Real-time studies in hydrocarbons have revealed a richness of chemistry involving the initial ionic species produced in radiolysis and photoionization. A modified radical cation mechanism patterned after the core mechanism for alkane radiolysis-formation of radical cations and their disappearance via ion-molecule reactions - is capable of explaining a wide range of observations in high-energy photochemistry, and thus unifies two high-energy regimes. Fundamental studies of radical cations sugges… more
Date: November 1, 1992
Creator: Werst, D. W. & Trifunac, A. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Kinetics of the transpassive oxidation of pyrite. Technical progress report, July 1, 1992--October 20, 1992

Description: In the transpassive region, about 0.4 to 0.8 V (SCE), aggressive oxidation of pyrite occurred. The reaction products in this region were Fe(III) oxide, sulfate ion and partially oxidized sulfur intermediates. The growth kinetics of the reaction of pyrite were studied using chronoamperometry measurement with both stationary and rotating disk electrodes. The effect of electrode rotation speed, solution pH and temperature were examined. Potentiostatic measurements were well correlated by a paralin… more
Date: December 31, 1992
Creator: Hu, Weibai; Huang, Qinping; Zhu, Ximeng; Li, Jun; Bodily, D. M. & Wadsworth, M. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Probing flame chemistry with MBMS, theory, and modeling. Annual progress report, July 15, 1991--July 14, 1992

Description: The program objective is to establish kinetics of combustion and molecular weight growth in C{sub 3} hydrocarbon flames as part of an ongoing study of flame chemistry. Specific reactions to be studies are (1) the oxidation reactions of O and OH with C{sub 3}`s and (2) the growth reactions of C{sub 3}H{sub 5} and C{sub 3}H{sub 3} with themselves and with unsaturated hydrocarbons. Our approach combines molecular-beam mass spectroscopy (MBMS) experiments which give concentrations of stable species… more
Date: March 1, 1992
Creator: Westmoreland, P. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fundamental studies of catalytic processing of synthetic liquids. Quarterly progress report, October 1, 1991--December 31, 1991

Description: This project revolves around understanding the fundamental processes involved in the catalytic removal of harmful oxygenated organics present in coal liquids. We are modelling the complex type of sulfided Mo catalyst proposed for these reactions with simple single crystal surfaces. These display a controlled range and number of reaction sites and can be extensively characterized by surface science techniques. We then investigate the reaction pathways for representative simple oxygenates upon th… more
Date: January 22, 1992
Creator: Watson, P. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

[Ligand intermediates in metal-catalyzed reactions]. Progress report, July 1, 1989--June 30, 1992

Description: This report consists of sections on sigma bond complexes of alkenes, a new carbon-hydrogen bond activation reaction of alkene complexes, carbon-hydrogen bond migrations in alkylidene complexes, carbon- hydrogen bond migrations in alkyne complexes, synthesis, structure and reactivity of C{sub x} complexes, synthesis and reactivity of alcohol and ether complexes, new catalysts for the epimerization of secondary alcohols; carbon-hydrogen bond activation in alkoxide complexes, pi/sigma equilibria i… more
Date: August 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A novel process for methanol synthesis. Progress report, March 1, 1992--May 31, 1992

Description: A bench-scale reactor is being used to conduct studies of the conversion of synthesis gas to methanol (MeOH) by a novel process. In previous reports, we provided evidence for a two-step reaction in series, the carbonylation reaction taking place mainly in a non-equilibrium region in the vicinity of the copper chromite surface, and the hydrogenolysis reaction taking place on the surface of the copper chromite. Interaction between the two catalysts enhances the rate of methanol formation. In this… more
Date: September 1, 1992
Creator: Tierney, J. W. & Wender, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Catalytic conversion of light alkanes

Description: The second Quarterly Report of 1992 on the Catalytic Conversion of Light Alkanes reviews the work done between April 1, 1992 and June 31, 1992 on the Cooperative Agreement. The mission of this work is to devise a new catalyst which can be used in a simple economic process to convert the light alkanes in natural gas to oxygenate products that can either be used as clean-burning, high octane liquid fuels, as fuel components or as precursors to liquid hydrocarbon uwspomdon fuel. During the past qu… more
Date: June 30, 1992
Creator: Lyons, J. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Radiation and Photochemistry Section annual report, October 1991--September 1992

Description: A survey is presented of research on reactive intermediates in the condensed phase and chemistry induced by energetic radiation. The survey is presented in two major parts: (1) ions, excited states, and other transients in condensed phase; and (2) role of solvents in chemical reactivity. Accelerator activities (20-MeV linac, 3-MeV Van de Graaff) are summarized.
Date: November 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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