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This paper presents a study of the chemical shift of the phenol hydroxyl group as a function of concentration and temperature in cyclohexane, methylcyclohexane and carbon tetrachloride solutions. The chemical shift of monomeric phenol has been found. For these solutions monomertrimer equilibrium is observed within the entire temperature range and within a wide concentration range. At low phenol concentrations, from 1 to 3 mole-%, the monomer-dimer equilibrium is observed in cyclohexane, methylcyclohexane and carbon tetrachloride solutions. Chemical shift of the hydroxyl group of trimeric phenol is temperature-dependent. From the experimental data the association constants and thermodynamic functions of the systems under study have been determined. The association constants differ for the above systems at the same temperatures. Association entropy ΔS changes from one system to another, while ΔH is the same for all systems.

The applications of pyrolysis gas chromatography for quantitative analysis of copolymers and for the evaluation of their microstructure are described. Three types of widely accepted pyrolyzers were examined to determine their different applications and to select the most satisfactory ones for quantitative analysis. It was established that all types of pyrolyzers may be used for the determination of the composition of copolymers and that a Curie-point pyrolyzer is preferable for the evaluation of polymer microstructure. The pyrolysis gas chromatographic conditions of different copolymers and rubber mixtures are given in this paper. The linear relationship between the ratio of characteristic peak areas and the ratio of the concentration of monomer units in copolymers was used for the determination of copolymer composition using the pyrograms. The difference that was found between the ratio of peak areas for block and random copolymers was used for the evaluation of the sequence distribution of monomer units. The optimum pyrolysis temperature was determined for that purpose. An equation for calculating the contents of monomer units in blocks is suggested.

Three types of pyrolysis device (an electrically heated filament unit, a quartz-tube furnace unit and a Curie-point pyrolyzer) were used in the decomposition of polymers. The pyrolysis temperature was varied in the range 420–980°.

Measurements are made of the photoelectromagnetic effect and photoconductivity in n- and p-type Ge doped with Au and Mn in the temperature range ∽ 330–90°K. The Au capture coefficients at 300°K are found to be: α0n = 5 × 10−10, α−n = 2 × 10−9, α = p = 1 × 10 −7 ( cm 3 sec ) ; while for Mn one obtains: α0n = 2 × 10−9, α−n = 4 × 10−10, α= = 6 × 10−10 (cm3/sec). The α= temperature dependence is of the form T−n, where n = 3.5 for Au and 4.5 for Mn. α0n and αn for Mn, as well as α0n for Au, are but weakly temperature dependent. The α-values obtained are in agreement with the analyses of the trapping phenomena in n-type samples. The experimental results are discussed and compared with the data given by other authors.

Tchoumakov I.S., Alexeeva L.I. Un nouveau gisement de mammifères villafranchiens en Tunisie. In: Documents des Laboratoires de Géologie de la Faculté des Sciences de Lyon, n°45, 1971. Notes et mémoires. pp. 149-151.

Publisher Summary The Wittig reaction is considered one of the fundamental synthetic methods of modern organic chemistry. It is the most convenient route to unsaturated compounds. The remarkable features of this reaction include mild reaction conditions, high quantitative yields, and the absence of migration of the bond formed. A number of natural compounds such as carotenoids and methylenic steroids are synthesized by using this reaction. This chapter summarizes the advances in the application of the Wittig reaction in the carbohydrate field. The Wittig reaction involves the interaction of an oxo compound with phosphonium ylides, through an intermediate betaine to yield the appropriate alkene and triphenylphosphine oxide. The Wittig reaction generally results in the preponderant formation of the trans-isomer. The yield of the cis-isomer is increased with decrease in stability of the phosphorane. It is noted that the application of the Wittig reaction in the carbohydrate field is accompanied by certain difficulties. A correct choice of the initial sugar components is the main problem, owing to the basicity of phosphoranes.