Rechnersteuerung der Spektrometer in einem Mikroanalysen-Laboratorium

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.     

Nitrous Deamination of β-Allenic Amines

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.     

Polymorphisme de l'hydrure de magnesium sous haute pression

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.     

Synthesis of 5-hydroxymethyl-2-furancarboxaldehyde catalysed by cationic exchange resins. Part 2. Analysis and discussion of the effect of the main parameters on the HMF output

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.     

Synthese et caracterisation du pentafluorotellurate (IV) de sodium NaTeF5

Sodium pentafluorotellurate (IV) NaTeF₅ has been prepared by slow evaporation of a $\text{1}\text{1}$ mixture of sodium fluoride and tellurium dioxyde in 50 % aqueous hydrofluoric acid.NaTeF₅ has an orthorhombic structure, parameters of which are $\text{a}\text{= 9.10}{}_5\text{A}\text{?}$$\text{b}\text{= 11.30}{}_6\text{A}\text{?}$$\text{c}\text{= 10.12}\text{A}\text{?}$     

Modelling and numerical simulation of an epitaxial reactor

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.     

Specific induction of lauric acid ω-hydroxylase by clofibrate,diethylhexyl-phthalate and 2,4-dichlorophenoxyacetic acid in higher plants

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.     

Review of Précis de toxicomanies.

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)     

Griffith Cracks at the Nanoscale

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.