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901.
Ermittlung der chemischen Zusammensetzung der Oberfläche mit Hilfe eines Auger-Spektrometers, eines Elektronenenergie-Spektrometers (ESCA) und einer lonen-Mikrosonde in Verbindung mit einem Rechnersystem. Beschreibung des Interface und der Verbindung der Geräte mit dem Rechner. Steuerung der Geräte durch den Rechner, Erfassung der Analysenwerte der Geräte im Rechner und alphanumerische und graphische Darstellung der Ergebnisse. Untersuchung der Oberfläche eines aluminiumberuhigten Sauerstoffauf-blasstahles nach dem Entfetten und Glühen. 相似文献
902.
Deamination of seven allenic amines 1Ad to 1Dd and 14, 15, 16 was performed in protic and aprotic media. Homoallenic participation has been shown to be the major process in deamination of acyclic amines 1Cd and 1Dd . In the latter case, intramolecular retentive substitution was observed. 相似文献
903.
Jean-Pierre Bastide Bernard Bonnetot Jean-Marie Létoffé Pierre Claudy 《Materials Research Bulletin》1980,15(9):1215-1224
The structural relationships in magnesium hydride have been studied under P-T conditions up to 80 kbar and 900°C, α-MgH2 has a rutile structure under normal conditions and transforms into two new phases under high pressures: β-MgH2 and γ-MgH2 with a hexagonal (pseudocubic) and an orthorhombic unit-cell structure respectively. β-MgH2 may be related to a fluorite type form (with an eight-coordination for Mg), transforming when the pressure is released into γ-MgH2 having the αPbO2 type structure (with a six-coordination for Mg). The density of the α-MgH2 and γ-MgH2 are very similar, but the density of the β-MgH2 fluorite form is some 25% greater than that of the rutile type. Thus MgH2 seems to exhibit under high pressure conditions the typical behavior of a number of rutile type compounds MX2 such as fluorides or oxides. 相似文献
904.
Daniel Mercadier Luc Rigal Antoine Gaset Jean-Pierre Gorrichon 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1981,31(1):497-502
The effects of the sugar and catalyst concentrations on the dehydration reaction of D -fructose to 5-hydroxymethyl-2-furancarboxaldehyde when a triphasic medium water-solvent-ion exchange resin is used, are described. 相似文献
905.
Jean-Pierre Bastide Patrick Germain Jack Thourey Guy Pérachon 《Materials Research Bulletin》1984,19(1):7-10
Sodium pentafluorotellurate (IV) NaTeF5 has been prepared by slow evaporation of a mixture of sodium fluoride and tellurium dioxyde in 50 % aqueous hydrofluoric acid.NaTeF5 has an orthorhombic structure, parameters of which are 相似文献
906.
907.
Jean-Pierre Babary Jorge Lopes de Souza Leao 《Mathematics and computers in simulation》1984,26(3):210-217
The purpose of this article concerns the modelling of the thermal behaviour of an epitaxial reactor. Numerical simulations (FORTRAN and CSMP III) are very useful for testing the validity of simplified models obtained from a complex non linear distributed parameter system. 相似文献
908.
Recently, we have found in plant microsomes two laurate hydroxylases that catalyze the terminal hydroxylation or the in-chain
hydroxylation of the fatty acid. These two hydroxylases, which are both cytochrome P-450 enzymes, are never found in the same
plant. This study shows that the hypolipidemic drug clofibrate induces the lauric acid ω-hydroxylase activity inVicia and soybean seedlings. The marked increase in activity (>20-fold) produced by clofibrate was dose-dependent but was not paralleled
by an enhancement of bulk cytochrome P-450 or cinnamic acid 4-hydroxylase. Compounds related to clofibrate by structure (2,4-dichlorophenoxyacetic
acid) or effects (diethylhexyl-phthalate) also stimulated the ω-hydroxylating system in these plants. In contrast, the lauric
acid in-chain hydroxylase from Jerusalem artichoke tubers was induced less than cinnamic acid 4-hydroxylase activity and bulk
cytochrome P-450 in tissues incubated in clofibrate solution. This suggests that clofibrate induces preferentially the laurate
ω-hydroxylating isozyme in plants. 相似文献
909.
Reviews the book, Précis de toxicomanies by Jean Bergeret and Jean Leblanc (1984). In this volume Bergeret and Leblanc discuss the treatment of drug-addiction in all its reality. Indeed, several aspects of the problem are approached: pharmacological, psychological, sociological and relational. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
910.
Sheldon M. Wiederhorn Theo Fett Jean-Pierre Guin Matteo Ciccotti 《International Journal of Applied Glass Science》2013,4(2):76-86
When Griffith presented his famous theory of crack stability in elastic materials in the early twentieth century, he was unable to provide much detail on the structure of cracks at the nanometer level of resolution. Now, almost 100 years later, techniques such as transmission electron microscopy, atomic force microscope, nuclear reaction analysis, and nuclear reflection are available to achieve this level of resolution. Here, we review the kind of data obtained using these techniques and the implications of the data vis-á-vis cracks in silicate glasses. Measurements by atomic force microscopy provide information on the size of the nonlinear zone at crack tips in glass, on environmental conditions at crack tips, and on the possibility of cavity formation as a mechanism of crack growth. Examination by nuclear reaction analysis and neutron reflection of fresh fracture surfaces formed in water has yielded information on water penetration through the glass surrounding the crack tip, to a resolution of 3–5 nm. Improvement of measurement techniques in the coming years should enable us to study crack tips in glasses to even higher levels of resolution and to answer more detailed questions concerning the level of stress and the size of the nonlinear zone at the crack tip. 相似文献