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Effect of substituents on the C-13 NMR chemical shifts of para-substituted alpha-phenyl-beta-pyridylacrylic acids
(Elsevier, Amsterdam, 1997)
The C-13 NMR spectra of para-substituted alpha-phenylcinnamic and 3- and 4-pyridylacrylic acids, with a wide range of substituents effects, were determined in deuterated dimethylsulfoxide (DMSO-d(6)). The effect of ...
Comparison of critical ΔT-values with R-parameters of thermally shocked alumina refractories
(Expert Fachmedien GmbH, 1997)
The thermal shock stability of ceramic materials can be characterized using critical temperature difference or resistance parameters. Resistance parameters R and Rst are used in this paper. Two ways of representing thermal ...
Quantum approach to GaAs MESFETs
(IEEE, 1997)
This paper is completely devoted to an original method of determination of carriers distribution in GaAs MESFET channel based on the investigation of transport equation including a quantum correction term.
Temperature-dependent hydrogen electrochemistry on platinum low-index single-crystal surfaces in acid solutions
(Amer Chemical Soc, Washington, 1997)
The hydrogen evolution (HER) and the hydrogen oxidation reaction (HOR) were studied on platinum single crystals in a sulfuric acid solution over the temperature range 274-333 K. We found, for the first rime, that at a fixed ...
Thermogravimetric characterisation of poly(methyl methacrylate) photopolymerised by colloidal cadmium sulphide
(Springer, Dordrecht, 1997)
The thermal stability of poly(methyl methacrylate) (PMMA) photopolymerised using colloidal cadmium sulphide as the photoinitiator was studied by thermogravimetry (TG) and differential TG (DTG). The thermal stability of the ...
Electrooxidation of H-2/CO mixtures on a well-characterized Pt75Mo25 alloy surface
(Amer Chemical Soc, Washington, 1997)
The electrochemical oxidation of hydrogen in the presence of carbon monoxide (0.05-2%) on a well-characterized Pt75Mo25 alloy surface was examined using the rotating disk electrode technique in 0.5 M H2SO4 at 333 K. The ...
Relationship between fracture resistance and critical temperature difference in ceramic materials
(Plenum Publ Corp, New York, 1997)
The resistance of ceramics to thermal shock can be characterized using either a parameter of their resistance to fracture R or the critical temperature difference Delta T-c = Delta T-c (Bi). It is demonstrated that a ...
Size distribution of ultrafine spherical ceramic powders obtained by ultrasonic spray pyrolysis
(Trans Tech Publications Ltd., 1997)
Comparative analysis of experimentally determined particle size distribution and theoretically calculated aerosole drop size distribution (obtained on the basis of 3D model of spherical / elliptical waves generated by the ...
Preparation of thermoplastic starch
(Serbian Chemical Society, Belgrade, 1997)
Native starch and WX-starch, i.e., native starch enriched with amylopectin, were mixed with plasticizers and thermomechanically treated in a twin screw mixer in order to obtain thermoplastic starch. Ethylene glycol, propane ...
Synthesis and formation mechanism of submicrometre spherical cordierite powders by ultrasonic spray pyrolysis
(Chapman Hall Ltd, London, 1997)
Cordierite powders containing very pure submicrometre spherical particles have been synthesized by the ultrasonic spray pyrolysis. Aqueous solutions of silicic acid, Al(NO3)(3) . 9H(2)O and MgCl2 . 6H(2)O were used as ...