Results 181 to 190 of about 2,477 (226)
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Isomorphous substitution in the microporous titanosilicate ETS-10
Microporous Materials, 1996Abstract Silicon has been isomorphously substituted by aluminium and gallium in the microporous titanosilicate ETS-10 to produce ETAS-10 and ETGS-10 respectively. For aluminium substitution a series of samples have been prepared with Al/Ti ratios ranging from 0.10 to 0.48. Both aluminium and gallium substitute exclusively in tetrahedral silicon sites
M.W. Anderson +5 more
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Isomorphous Substitution in Zeolite Catalysts
1989Publisher Summary The high silica zeolites, discovered first by Mobil, brought an enormous amount of studies in several directions. Among them, many attempts were done to incorporate in the framework elements different from silicon and aluminum, with the aim of synthesizing zeolites possessing novel catalytic properties. Assessing the occurrence of a
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Isomorphic substitutions in afghanite: Identification of the mineral
Geology of Ore Deposits, 2009Samples of afghanite, (Na,Ca,K)8 (Al6Si6O24)(SO4,Cl,CO3)3 · H2O, from the Malaya Bystraya and Tultui lazurite deposits in the Baikal region have been studied with X-ray diffraction and an electron microprobe. The unit-cell dimensions a and c of the examined afghanite samples range from 12.729 to 12.762 &0A and from 21.385 to 21.415 &0A.
A. N. Sapozhnikov +3 more
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Simplified synthesis of isomorphously nickel substituted ZSM-5
Journal of Porous Materials, 2007Isomorphously nickel-substituted nano-crystalline ZSM-5 is synthesized in the absence of acidic aqueous fluoride medium incorporating simple and low-cost metal inorganic salt precursor NiCl2.6H2O instead of large organic cationic salt like bis (tetraethyl ammonium) tetrachloronickelate (II) with less water quantity to minimize the synthesis waste. PXRD,
Kalpesh B. Sidhpuria +3 more
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Isomorphic A‐Site Substitution on Sillenite‐Type Compounds
Journal of the American Ceramic Society, 2004Investigations of A‐site substitution in sillenite‐type compounds showed that only a substituent ion with a lone‐electron pair can be successfully incorporated onto the A‐site in place of Bi 3+ . This is because the stability of sillenite structural polyhedra is conditioned by the presence of
Matjaz Valant +2 more
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Isomorphous Substitution in Zeolite Zsm-5
1989A series of metal-substituted silicalite samples has been prepared. Preliminary experiments indicate that some of the metal species occupy framework sites in the zeolite structure. An interesting feature of all of the products is the large size of the crystallites, some being as much as 500μm long.
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Répartition des substitutions isomorphes dans la muscovite
Bulletin du Groupe français des argiles, 1964Radoslovich published a refinement of muscovite structure (Acta Cryst. 1960-13-919) in which he as certained a rotation of the tetrahedrons and localization of the isomorphic substitutions in only one out of the two tetrahedral positions. The nature of the central atom was deduced from the length of the "Si" - O bonds.
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Isomorphous substitution in polyethyleneterephthalate
Polymer Science U.S.S.R., 1962B.V. Petukhov, S.M. Kondratova
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Structure réelle de la muscovite répartition des substitutions isomorphes
Bulletin du Groupe français des argiles, 1964The tetrahedral substitutions of aluminium for silicon produce an X-ray diffusion outside the BRAGG regions. These diffusions are concentrated on reciprocal planes perpendicular to the plane of the lamination passing through the reciprocal lines h k.
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Isomorphous Substitution in Enamel Apatite
The Journal of the American Dental Association, 1953A S, POSNER, S R, STEPHENSON
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