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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 ...
Structure optimization of polylactide microcapsules for controlled drug release
(Trans Tech Publications Ltd, Durnten-Zurich, 1998)
The influence of starting material properties on physical characteristics and drug release kinetics of poly-L-lactide microcapsules was investigated. The density, the distribution of the diameter size of microcapsules, the ...
Formation of AlPO4-15 and CoAPO-15 in the presence of hexamethylenetetramine
(Butterworth-Heinemann, 1990)
Two materials, AIPO4-15 and CoAPO-15, with the same aluminophosphate lattice have been obtained by hydrothermal synthesis in the presence of hexamethylenetetramine (HMTA). Their formation is attributed to the influence of ...
Mass spectrometric investigations of some N‐cycloalkyl and N‐aryl fluoroacetamides
(Wiley, Hoboken, 1995)
The electron‐ionization induced mass spectra of some N‐monosubstituted fluoroacetamides of the general formula FCH2CONHR, in which the substituent R is (C3C7) cycloalkyl, phenyl, 4‐methylphenyl, 4‐carbo‐methoxyphenyl, ...
The retention behavior of some anilides on unconventional TLC supports
(Akademiai Kiado Zrt, Budapest, 1997)
The TLC retention behavior of formanilide and I substituted acetanilides on starch and cellulose layers has been studied using aqueous mobile phases with methanol, acetonitrile, acetone, and 1-propanol as modifiers, R-Mw ...
Temperature-programmed desorption mass spectrometric study of the surface properties of glassy carbon
(Wiley, Hoboken, 1996)
The temperature-programmed desorption (TPD) method combined with mass spectrometric analysis has been applied to the characterization of glassy carbon (GC) and modified glassy carbon surfaces. Five different samples of GC ...
Nonlinear optical effects in asymmetric AlGaAs/GaAs semiconductor quantum wells
(Trans Tech-Scitec Publications Ltd, Durnten-Zurich, 1998)
Optical nonlinearities in three-level asymmetric semiconductor quantum wells (QW) are analyzed (optical rectification, second harmonic generation (SHG)). The influence of permanent dipole moments on SHG conversion efficiency ...
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.