<?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%">Niphadkar, P. S.</style></author><author><style face="normal" font="default" size="100%">Patil, K. R.</style></author><author><style face="normal" font="default" size="100%">Joshi, P. N.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Characterization of surface acid sites in tin-silicalite-1 (Sn-MFI) molecular sieve by X-ray photoelectron spectroscopy</style></title><secondary-title><style face="normal" font="default" size="100%">Microporous and Mesoporous Materials</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Lewis acidity</style></keyword><keyword><style  face="normal" font="default" size="100%">Pyridine chemisorption</style></keyword><keyword><style  face="normal" font="default" size="100%">SiO2/SnO2 molar ratio</style></keyword><keyword><style  face="normal" font="default" size="100%">Sn-MFI</style></keyword><keyword><style  face="normal" font="default" size="100%">XPS</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAY</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">1-3</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%">141</style></volume><pages><style face="normal" font="default" size="100%">236-240</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The nature, strength and density of surface acid sites in Sn-MFI molecular sieves with different Sn-content were characterized by N 1s high resolution photoelectron peak of chemisorbed pyridine in combination with pyridine-IR and TPAD. Two peaks emerged at 399.5 +/- 0.2 and 401.5 +/- 0.2 eV by deconvoluting composite N is peak were assigned to chemisorbed pyridine on weak and relatively strong Lewis acid sites, respectively. The relative percentage of strong Lewis acid sites was found to increase with the decrease of framework Sn content. A close agreement was observed between the ratios of weak Lewis acid sites to strong Lewis acid sites obtained from XPS and TPAD. (C) 2010 Elsevier Inc. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1-3</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">3.58</style></custom4></record></records></xml>