<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Shylesh, S.</style></author><author><style face="normal" font="default" size="100%">Singh, A. R.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Heterogenized vanadyl cations over modified silica surfaces: a comprehensive understanding toward the structural property and catalytic activity difference over mesoporous and amorphous silica supports</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Catalysis</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">3-APTS</style></keyword><keyword><style  face="normal" font="default" size="100%">mesoporous solids</style></keyword><keyword><style  face="normal" font="default" size="100%">Oxidation</style></keyword><keyword><style  face="normal" font="default" size="100%">Silica gel</style></keyword><keyword><style  face="normal" font="default" size="100%">Vanadium</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">NOV</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">1</style></number><publisher><style face="normal" font="default" size="100%">ACADEMIC PRESS INC ELSEVIER SCIENCE</style></publisher><pub-location><style face="normal" font="default" size="100%">525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA</style></pub-location><volume><style face="normal" font="default" size="100%">244</style></volume><pages><style face="normal" font="default" size="100%">52-64</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Using a postsynthesis grafting method, 3-aminopropyltriethoxysilane (3-APTS) was functionalized over silica gel and mesoporous silica materials like SBA-15 and MCM-41. Vanadyl cations were then immobilized over the functionalized amino groups of the silica samples and used as a catalyst in the liquid-phase oxidation reaction of cyclohexane. Elemental analysis, PXRD, TEM, N-2 adsorption-desorption isotherms, FTIR, C-13 and Si-29 MAS NMR, UV-vis, and EPR techniques were used to characterize the developed materials. Characterization results suggest that the percentage of 3-APTS grafting depends on the number of isolated and genlinal silanol sites of the support material, the solvents used during the grafting reactions, and the sample pretreatment conditions. We found that using toluene as the dispersing medium and Si-MCM-41 as a support provides the maximum amount of amine functionalization, and thereby the highest percentage of vanadium immobilization. Catalytic activity and metal leaching studies show that vanadium-immobilized mesoporous solids are more active and stable than the silica gel-functionalized vanadium catalyst and a framework-substituted V-MCM-41 catalyst. The enhanced activity and stability of the immobilized vanadium catalysts compared with the V-MCM-41 and silica gel samples are attributed to the active metal site isolations, as well as to the spatial restrictions imparted from the concave silica surfaces of the mesoporous solids rather than the convex silica surfaces of the silica gel sample. (c) 2006 Published by Elsevier Inc.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;</style></custom3><custom4><style face="normal" font="default" size="100%">7.354</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Shylesh, S.</style></author><author><style face="normal" font="default" size="100%">Kapoor, Mahendra P.</style></author><author><style face="normal" font="default" size="100%">Juneja, Lekh R.</style></author><author><style face="normal" font="default" size="100%">Samuel, Prinson R.</style></author><author><style face="normal" font="default" size="100%">Srilakshmi, Ch</style></author><author><style face="normal" font="default" size="100%">Singh, A. R.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Catalytic meerwein-ponndorf-verley reductions over mesoporous silica supports: rational design of hydrophobic mesoporous silica for enhanced stability of aluminum doped mesoporous catalysts</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Molecular Catalysis A-Chemical</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Aluminum isopropoxide</style></keyword><keyword><style  face="normal" font="default" size="100%">Mesoporous silica</style></keyword><keyword><style  face="normal" font="default" size="100%">Organosilica</style></keyword><keyword><style  face="normal" font="default" size="100%">reduction</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAR</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">1-2</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE BV</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS</style></pub-location><volume><style face="normal" font="default" size="100%">301</style></volume><pages><style face="normal" font="default" size="100%">118-126</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;A series of aluminum isopropoxide-grafted mesoporous organosilica having ethane (-CH(2)-CH(2)-) and ethene (-CH=CH-) groups in the frame wall positions (ethane-silica, ethene-silica) as well as mesoporous silicas (MCM-41, MCM-48. SBA-15) through siloxide linkages were fabricated. The samples were used as catalysts in the Meerwein-Ponndorf-Verley reduction of ketones and aldehydes of different nature and size using secondary alcohols as the hydrogen transfer agents. Aluminum isopropoxide supported mesoporous silica samples show higher catalytic conversion and among them, the one-dimensionally channel oriented Si-MCM-41 supported aluminum isopropoxide shows better results than the three-dimensional Si-MCM-48 and the large pore Si-SBA-15. Compared to aluminum isopropoxide-grafted mesoporous silica samples, aluminum alkoxide-grafted organosilica samples shows better catalytic activity even in the presence of 10% of water and the better stability is attributed to the presence of integrated hydrophobic organic groups in the frame wall positions. (C) 2008 Elsevier B.V. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">2.872</style></custom4></record></records></xml>