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Isomorphous element substitution in the chabazite-like aluminophosphate framework
(Akademiai Kiado Zrt, Budapest, 1998)
Thermal investigations and Fenske-Hall SCF MO calculations have been used for studying isomorphous element substitution in the chabazite-like aluminophosphate framework prepared in the presence of tetraethylammonium hydroxide ...
Preparation of aluminophosphate molecular sieves in the presence of nickel( II) and copper( II)
(Butterworth-Heinemann, 1991)
Nickel(ll)-substituted aluminophosphates of structure types 21 and 12 (NiAPO-21 and NiAPO-12) have been prepared hydrothermally in the presence of ethylenediamine as the template. U.v.-visible spectroscopy of NiAPO-21 ...
Thermal investigations of some AlPO and MeAPO materials prepared in the presence of HF
(Elsevier, Amsterdam, 1997)
Hydrothermal synthesis of chabazite-like AlPO4 in a fluoride medium, using piperidine as the structure directing agent, is also successful in the preparation of transition-metal-modified AlPO products. The transition metal ...
Thermal investigation of some chelate Ni(II) complexes
(Serbian Chemical Society, Belgrade, 1999)
Several diamine-nickel(II) complexes have been prepared and the kinetic parameters of their decomposition reactions investigated. The complexes undergo a gradual thermal decomposition. First, water is lost, followed by the ...
A novel open-framework sodium zincophosphate with isomorphous cobalt(II) substitution
(Royal Society of Chemistry, 1995)
A novel anionic cobalt-substituted zincophosphate framework with a hexagonal unit cell of composition Na6[Co0.2Zn0.8PO4]6·9H2O is synthesised and its crystal structure determined by single crystal X-ray diffraction.
Phase-transfer catalyzed N-ethylation of N-ethyl-2-phenylacetamide
(Natl Inst Science Communication, New Delhi, 1996)
Phase-transfer catalyzed N-ethylations of N-ethyl-2-phenylacetamide (EPA) in the presence of powdered KOH (solid-liquid system) have been carried out in order to establish the effect of catalyst structure on the reaction. ...
A CoAPO-34 derived from a triclinic precursor prepared in the presence of HF
(Elsevier Science Inc., 1997)
The fluoride route of synthesis of AIPO,-34 is also successful in the preparation of its cobalt modified product (CoAPO-34). The triclinic precursor of CoAPO-34 has been synthesized in the presence of HF and piperidine. ...
Retention behavior of some amides in reversed- and normal-phase thin-layer chromatography
(Springer Heidelberg, Heidelberg, 1992)
The retention behavior and separation ability of reversed- and normal-phase TLC with, polar and nonpolar mobile phases, has been studied by measuring the retentions of a series of amides. The retention behavior and separation ...
On the formation of CoAPSO-44
(Butterworth-Heinemann, 1992)
Hydrothermal synthesis of CoAPSO-44 in the presence of cyclohexylamine (CHA) as the template is generally accompanied by the formation of an unknown phase, “Co(APSO)N.” Electronic spectroscopy indicates that CO(APSO)N ...
Resistance parameters and water quench test as criteria of thermal shock behaviour of alumina based refractories
(Taylor & Francis Ltd, Abingdon, 1999)
The materials investigated were five alumina based commercial refractories with different contents of Al2O3 + TiO2 from 28 to 78%. Thermal (k thermal conductivity, alpha coefficient of thermal expansion) and mechanical (E ...