01985nas a2200277   4500008004100000022001400041245011000055210006900165260007400234300001200308490000800320520103100328653001601359653001101375653001301386653002401399653001401423653001701437100002701454700002401481700002001505700002501525700002001550700001701570856012001587       2007                        eng d  a1520-610600aNCL-7, a novel all silica analog of polymorph B rich member of BEA family: synthesis and characterization0 aNCL7 a novel all silica analog of polymorph B rich member of BEA  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbJapan Assoc ZeolitescAPR  a108-1140 v1013 a<p>{Polymorph B-rich BEA type structure, NCL-7, was synthesized using hydrothermal method in fluoride medium using perchloric acid as promoter. The samples were characterized using XRD, low temperature N-2-adsorption and Si-29 MASNMR. As the structure of beta is highly disordered Rietveld refinement of powder XRD patterns is precluded. Phase composition is derived using the simulated patterns for the random intergrowths of polymorph A and B by DIFFaX. The stacking direction c' is perpendicular to the a'b' plane of the layer. The composition of polymorph B is found to be ca. 60-65%. Two other structures namely NCL-5 and NCL-6 with varying degree of polymorph B enrichment were also synthesized. Synthesis parameters such as effect of H2O/SiO2, TEAOH/SiO2, HClO4/SiO2 and crystallization temperature were studied thoroughly. The present article explains for the first time the synthesis and characterization of NCL-7, an analog of BEA type family with enrichment of polymorph B and its comparison with normal beta (*</p>10aB-polymorph10aDIFFaX10aPromoter10aReitveld refinement10asynthesis10azeolite beta1 aKadgaonkar, Mahesh, D.1 aKasture, Mahesh, W.1 aBhange, Deu, S.1 aJoshi, Praphulla, N.1 aRamaswamy, Veda1 aKumar, Rajiv  uhttps://library.ncl.res.in/content/ncl-7-novel-all-silica-analog-polymorph-b-rich-member-bea-family-synthesis-and-002437nas a2200301   4500008004100000022001400041245011900055210006900174260007300243300001000316490000800326520141300334653001501747653001001762653001001772653001001782653002701792653001401819653001301833100002701846700002401873700002001897700002501917700002001942700002401962700001701986856013202003       2007                        eng d  a1387-181100aSynthesis and characterization of NCL-5, NCL-6 and NCL-7: new zeolites enriched with polymorph B of the BEA family0 aSynthesis and characterization of NCL5 NCL6 and NCL7 new zeolite  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcSEP  a82-880 v1053 a<p>The synthesis of all-silica analogs of polymorph B-enriched zeolites of the BEA family denoted as NCL-5, NCL-6 and NCL-7 was realized hydrothermally at lower water content in fluoride medium using perchloric acid as promoter and terraethylammonium hydroxide as template. The present article explains the effect of different synthesis parameters on NCL-5, NCL-6 and NCL-7. The samples were characterized using XRD, low temperature N-2-adsorption, Si-29 MAS NMR and FTIR spectroscopy. The phase composition of the structures was derived using simulated patterns for the random intergrowths of polymorphs A and B using DIFFaX Code. The stacking direction c' is perpendicular to the a'b' plane of the layer. The phase composition of polymorph B derived using DIFFaX code was found to be 90-95%. 70-75% and 60-65% in NCL-5, NCL-6 and NCL-7, respectively. The gradual decrease of polymorph B concentration in these samples showed a correlation with the decrease in water/SiO2 molar ratio in gel. The framework FTIR spectral analysis of NCL-5 and all-silica-beta supported the postulation that significant enrichment of polymorph B in NCL-5 compared to that in all-silica-beta, as indicated by the relative intensities of pair of bands at 1097 and 1018 cm(-1) and 460 and 423 cm(-1) vibrations, leads to more tortuous channel structure associated with polymorph B. (C) 2007 Elsevier Inc. All riahts reserved.</p>10aBEA family10aNCL-510aNCL-610aNCL-710apolymorph B enrichment10asynthesis10azeolites1 aKadgaonkar, Mahesh, D.1 aKasture, Mahesh, W.1 aBhange, Deu, S.1 aJoshi, Praphulla, N.1 aRamaswamy, Veda1 aGupta, Narendra, M.1 aKumar, Rajiv  uhttps://library.ncl.res.in/content/synthesis-and-characterization-ncl-5-ncl-6-and-ncl-7-new-zeolites-enriched-polymorph-b-bea-002373nas a2200265   4500008004100000022001400041245013900055210006900194260011700263300001200380490000800392520134900400653002401749653002001773653001801793653002701811653002101838653002201859100001801881700001701899700002701916700001401943700001801957856013201975       2009                        eng d  a0920-586100aPhotocatalytic mineralization of benzene over gold containing titania nanotubes: role of adsorbed water and nanosize gold crystallites0 aPhotocatalytic mineralization of benzene over gold containing ti  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbCatalysis Soc India; Petrotech Soc; Indo US Sci & Technol ForumcMAR  a144-1510 v1413 a<p>Well aligned titania nanotubes, with surface area of similar to 150 m(2) g(-1) and average pore diameter of similar to 5 nm, have been synthesized by subjecting a mesoporous TiO(2) sample to alkaline treatment followed by calcination at different temperatures. Composite catalysts with gold particles dispersed in these nanotubes were also synthesized and their structural, morphological, optical and photocatalytic properties were examined. The catalytic activity of TiO(2) for UV-mediated photo-oxidation of benzene was found to be affected by several factors, such as the sample texture. presence of adsorbed water and gold crystallites. The overall conversion of benzene to form CO(2) followed a trend: Au/nanotube &gt; TiO(2) nanotubes &gt; mesoporous TiO(2). In situ IR spectroscopy revealed that the adsorption and reaction of benzene molecules gave rise to formation of certain phenolic species over TiO(2), while the temperature-programmed desorption (TPD) study showed that the Au/TiO(2) interfaces serve as distinct sites for the adsorption and activation of oxygen molecules. It is suggested that certain hydroxyl and oxygen ion radicals produced under UV-irradiation may promote the deep oxidation of surface phenolic species and phenoxyl (ArO center dot) type transient radicals. (c) 2008 Elsevier B.V. All rights reserved.</p>10aBenzene degradation10aGold containing10aPhotocatalyst10aRole of adsorbed water10aTiO(2) nanotubes10aTransient species1 aAwate, S., V.1 aSahu, R., K.1 aKadgaonkar, Mahesh, D.1 aKumar, R.1 aGupta, N., M.  uhttps://library.ncl.res.in/content/photocatalytic-mineralization-benzene-over-gold-containing-titania-nanotubes-role-adsorbed-0