01907nas a2200241   4500008004100000022001400041245012600055210006900181260007300250300001200323490000800335520103600343653001701379653001801396653001801414653001901432100001601451700002401467700002001491700001901511700001801530856011701548       2007                        eng d  a1381-116900aSulfonic acid functionalized mesoporous silicas and organosilicas: synthesis, characterization and catalytic applications0 aSulfonic acid functionalized mesoporous silicas and organosilica  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcSEP  a153-1580 v2743 a<p>Ethane bridged mesoporous organosilicas and MCM-41 having sulfonic acid groups in the pore channels were prepared by co-condensation method as well as grafting method, using 3-mercaptopropyltriethoxysilane (3-MPTS) as the sulfur precursor. TEM and N-2 sorption isotherm analysis revealed that the mesoporous structural ordering is retained after the functionalization and modifications of organic groups while FT-IR, Raman, XPS and solid-state C-13 CP MAS NMR shows the presence of sulfonic acid groups and the stability of the mesoporous framework. The catalytic activity of the developed materials was evaluated in the liquid phase Claisen-Schmidt condensation reaction of acetophenone with benzaldehyde, to probe the effect of mesoporous support surfaces as well as the role of preparation methods. Results showed that sulfonic acid functionalized ethane-silica samples were more active, selective and stable than the conventional sulfonic acid containing mesoporous catalysts. (c) 2007 Elsevier B.V. All rights reserved.</p>10acondensation10aethane-silica10aheterogeneity10asulfonic acids1 aShylesh, S.1 aSamuel, Prinson, P.1 aSrilakshmi, Ch.1 aParischa, Renu1 aSingh, A., P.  uhttps://library.ncl.res.in/content/sulfonic-acid-functionalized-mesoporous-silicas-and-organosilicas-synthesis-002068nas a2200241   4500008004100000022001400041245010400055210006900159260009200228300001200320490000600332520118900338653001401527653002501541653002701566653001801593100001601611700002501627700002101652700002001673700001801693856011501711       2011                        eng d  a1941-490000aSynthesis and characterization of bifunctional ethenylene bridged mesoporous organoaluminosilicates0 aSynthesis and characterization of bifunctional ethenylene bridge  a26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USAbAMER SCIENTIFIC PUBLISHERScAUG  a497-5020 v33 a<p>Bifunctional mesoporous organosilicas having -CH=CH- bridges and aluminium in tetrahedral coordination with tailorable pore sizes have been synthesized using a one-step templating method using cationic surfactants of different chain lengths. Unlike the conventional EtOH-HCl template extraction process, EtOH-NH(4)NO(3) was used as the surfactant-extracting medium and chemical analysis results suggest that through this procedure the mesoporous structure can be retained and dealumination can be minimized. The surfactant-extracted mesoporous solids display high surface area, pore volume and the pore size of the material varies in the range 2.6-3.6 nm, with respect to the alkyl chain length of the cationic surfactant. XRD and nitrogen physisorption studies further proved that the organosilicas are hydro thermally stable than the conventional Al-MCM-41 materials and their better stability is attributed to the thick pore walls as well as due to the presence of hydrophobic bridging ethenylene groups in the wall positions. The coupling of Al(4) with -CH=CH- bridges offer new prospects for the application of periodic mesoporous organosilicas in heterogeneous catalysis.</p>10aAluminium10aCationic Surfactants10aHydrothermal stability10aOrganosilicas1 aShylesh, S.1 aKapoor, Mahendra, P.1 aJuneja, Lekh, R.1 aSrilakshmi, Ch.1 aSingh, A., P.  uhttps://library.ncl.res.in/content/synthesis-and-characterization-bifunctional-ethenylene-bridged-mesoporous-0