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101.
Hamid Reza Rahimpour Majid Saidi Parisa Rostami Bruce C. Gates Mohammad Reza Rahimpour 《国际化学动力学杂志》2016,48(11):702-713
Kinetics of the hydroprocessing of anisole, a compound representative of lignin‐derived bio‐oils, catalyzed by a commercial sulfided CoMo/Al2O3, was determined at 8–20 bar pressure and 573–673 K with a once‐through flow reactor. The catalyst was sulfided in an atmosphere of H2 + H2S prior to the measurement of its performance. Selectivity‐conversion data were used as a basis for determining an approximate, partially quantified reaction network showing that hydrodeoxygenation (HDO), hydrogenolysis, and alkylation reactions take place simultaneously. The data indicate that these reactions can be stopped at the point where HDO is virtually completed and hydrogenation reactions (and thus H2 consumption) are minimized. Phenol was the major product of the reactions, with direct deoxygenation of anisole to give benzene being kinetically almost insignificant under our conditions. We infer that the scission of the Cmethyl–O bond is more facile than the scission of the Caromatic–O bond, so that the HDO of anisole likely proceeds substantially through the reactive intermediate phenol to give transalkylation products such as 2‐methylphenol. The data determine rates of formation of the major primary products. The data show that if oxygen removal is the main processing goal, higher temperatures and lower pressures are favored. 相似文献
102.
Philip W. Kletnieks Ann J. Liang Raluca Craciun Justin O. Ehresmann Dr. David M. Marcus Dr. Vinesh A. Bhirud Dr. Meghan M. Klaric Miranda J. Hayman Darryl R. Guenther Olesya P. Bagatchenko David A. Dixon Prof. Bruce C. Gates Prof. James F. Haw Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(26):7267-7267
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Bashir S Derrick PJ Critchley P Gates PJ Staunton J 《European journal of mass spectrometry (Chichester, England)》2003,9(1):61-70
Application of matrix-assisted laser desorption/ionization (MALDI) to the analysis of dextran and dextrin derivatives, specifically glucose saccharides, by time-of-flight (TOF) mass spectrometry has been reported. MALDI-TOF analysis was carried out on alpha-, beta- and gamma-cyclodextrin, two O-methylated-beta-cyclodextrins of differing degrees of substitution (DS) and dextrans (a linear glucose saccharide), as pure and doped solutions and as mixtures of two or more of these. Doping was carried out with trace amounts of inorganic salts. The purpose of the analysis of the cyclodextrins was to determine whether they would form inclusion complexes with the various cations added, or whether less specific cation addition/exchange was occurring either prior to desorption or in the gas phase. 相似文献
105.
Derek P. Gates Ron Rulkens Regina Dirk Paul Nguyen John K. Pudelski Rui Resendes 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):561-565
Abstract The limits of cyclopentadienyl ring-tilting in [l]ferrocenophanes are explored with the incorporation of group 16 elements and a first row element. In this paper the synthesis and ring-opening polymerisation (ROP) behaviour of highly strained chalcogen-and boron- bridged [l]ferrocenophanes will be described. 相似文献
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108.
Bruce C. Gates Tobin J. Marks 《Angewandte Chemie (International ed. in English)》2012,51(47):11644-11645
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110.
We investigate nonlinear oscillations in a fourth-order partialdifferential equation which models a suspension bridge. Previouswork establishes multiple periodic solutions when a parameterexceeds a certain eigenvalue. In this paper, we use Leray-Schauderdegree theory to prove that if the parameter is increased further,beyond a second eigenvalue, then additional solutions are created. 相似文献