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Intrinsic barriers for H-atom transfer reactions involving hydrocarbons

Description: Intrinsic barriers (formally the barrier in the absence of driving force) for H-atom transfer reactions are key parameters in Evans-Polyanyi and Marcus equations for estimating exothermic reaction barriers and are fundamentally significant for the insight they provide about bond reorganization energies for formation of transition state structures. Although knowable from experiment, relatively few of these barriers have been measured due to experimental difficulties in measuring rates for identi… more
Date: August 1, 1994
Creator: Camaioni, D. M.; Autrey, S. T. & Franz, J. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of biological coal gasification (MicGAS Process)

Description: The overall goal of the project is to develop an advanced, clean coal biogasification (MicGAS) Process. The objectives of the research during FY 1993--94 were to: (1) enhance kinetics of methane production (biogasification, biomethanation) from Texas lignite (TxL) by the Mic-1 consortium isolated and developed at ARCTECH, (2) increase coal solids loading, (3) optimize medium composition, and (4) reduce retention time. A closer analysis of the results described here indicate that biomethanation … more
Date: October 1, 1994
Creator: Walia, D. S. & Srivastava, K. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low severity coal liquefaction promoted by cyclic olefins. Quarterly report, January--March 1992

Description: The naphthalene hydrogenation performed thermally at 350 and 400{degrees}C showed no reactivity of the naphthalene. The Molyvan L catalyst precursor promoted a small amount of hydrogenation of naphthalene at 400{degrees}C as shown in Table 1. Reaction at the higher initial pressure of 1250 psi resulted in slightly more conversion of naplithalene and a higher production of tetralin but no decalin was observed. The naphthalene hydrogenation reactions with Molyvan L without sulfur yielded a slight… more
Date: October 1, 1992
Creator: Curtis, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The role of the resid solvent in co-processing with finely divided catalysts. Quarterly report April--June 1993

Description: The primary purpose of the work performed this quarter was to establish under thermal and catalytic reaction conditions whether hydrogen transfer occurred between cycloalkane type structures that are present in resids and heteroatomic species that are present in coal and liquefied coal. The research this quarter focused upon evaluating benzophenone (BENZ) as a model acceptor for hydrogen that might be transferred from a cycloalkane, perhydropyrene (PHP), under coprocessing conditions. Hence, a … more
Date: November 1, 1993
Creator: Curtis, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solvent Tailoring in Coal Liquefaction. Quarterly Report, October 1983-December 1983

Description: The contribution of transferable hydrogen in coal-derived solvents to coal conversion was investigated in a two-step process. Initially, the amount of transferable hydrogen in the coal-derived solvents was analyzed by spectroscopic methods and by catalytic dehydrogenation. The spectroscopic methods included carbon magnetic resonance, proton magnetic resonance as well as a combination of these two methods. Three of the methods gave nearly equivalent quantities for the amount of transferable hydr… more
Date: July 1, 1983
Creator: Tarrer, A. R.; Curtis, C. W.; Guin, J. A. & Williams, D. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simulations of Fluid Nitromethane Under Extreme Conditions

Description: We report density functional molecular dynamics simulations to determine the early chemical events of hot (T = 3000 K) and dense (1.97 g/cm{sup 3}, V/V{sub 0} = 0.68) nitromethane (CH{sub 3}NO{sub 2}). The first step in the decomposition process is an intermolecular proton abstraction mechanism that leads to the formation of CH{sub 3}NO{sub 2}H and the aci ion H{sub 2}CNO{sub 2}{sup -}, in support of evidence from static high-pressure and shock experiments. An intramolecular hydrogen transfer t… more
Date: July 15, 2003
Creator: Fried, L E; Reed, E J & Manaa, M R
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Solvent Tailoring in Coal Liquefaction. Quarterly Report, July-September 1983

Description: A series of twenty-three aromatic compounds were ranked for their donor solvent efficacy for the dissolution of Western Kentucky No. 9/14 coal. The transfer of hydrogen from the solvent to the coal fragments, as measured by coal conversion, was examined at three levels of available hydrogen. The hydrogen donors are ranked according to their ability to convert coal to THF solubles. Aromatic analogs of the donors showed little ability to convert coal to THF solubles. Factors which influence hydro… more
Date: January 1, 1983
Creator: Tarrer, A. R.; Curtis, C. W.; Guin, J. A. & Williams, D. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of transition states and radicals by negative ion photodetachment

Description: Negative ion photodetachment is a versatile tool for the production and study of transient neutral species such as reaction intermediates and free radicals. Photodetachment of the stable XHY{sup {minus}} anion provides a direct spectroscopic probe of the transition state region of the potential energy surface for the neutral hydrogen transfer reaction X + HY {yields} XH + Y, where X and Y are halogen atoms. The technique is especially sensitive to resonances, which occur at a specific energy, b… more
Date: December 1, 1991
Creator: Metz, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low severity coal liquefaction promoted by cyclic olefins

Description: Low severity coal liquefaction allows for solubilization of coal with reduced gas make. These lower severity conditions may result in some selective bond rupture. Promotion of coal solubilization through hydrogen transfer using highly active and effective hydrogen donors is the objective of this study. The highly effective donors being tested are cyclic olefins. Representative cyclic olefins are isotetralin, which is 1,4,5,8-tetrahydronaphthalene, and 1,4,5,8,9,10-hexahydroanthracene. These com… more
Date: July 27, 1992
Creator: Curtis, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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