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A new procedure was developed for building linear Z-isoprenoids from glutaraldehyde derivatives as nonisoprenoid precursors, and is illustrated by the synthesis of hexaprenol WC5OH.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 89–97, January, 1990.  相似文献   
3.
The effect of constant magnetic field on the rheological properties and freezing point of a number of high-paraffinicity oils is studied. It is established that the rheological behavior of oils in a magnetic field depends on the content of paraffin hydrocarbons, resins, and asphaltenes. An increase in the main rheological parameters upon the action of magnetic field is observed for high-paraffinicity oils with the increased content of neutral resins and a decrease, for high-paraffinicity oils with the increased content of acid resins. The activation energy of viscous flow is determined and the dependence of the rate of the recovery of rheological properties on the parameters of magnetic treatment and the ratio between the content of paraffin hydrocarbons and resin–asphaltene components is established for the magnetically treated oils of different compositions.  相似文献   
4.
The methylation and allylation of 6-(3-indolyl)indolo[2,3-b]carbazole were studied, and its trimethyl and mono-, di-, and triallyl derivatives were obtained.  相似文献   
5.
EPR and NMR studies show that in oxidation of gases with low concentrations of SO2 the molten active component of K/V and Cs/V catalysts becomes inhomogeneous and contains V5+ compounds having different activities.
, SO2 K/V Cs/V , V5+.
  相似文献   
6.
The coagulation ability of humic acids (HAs) obtained from mechanically activated high-moor peat has been investigated. The effects of the concentration and the methods of isolation of HAs from peat on the reversible aggregation of blood erythrocytes have been studied. The strength of aggregates of erythrocytes and the period of their aggregation have been found to depend on the concentration and composition of HAs.  相似文献   
7.
To optimize the compositions of liquid organic electrolytes for lithium power sources, it is useful to have the dependence of the conductivity on the lithium salt concentration in a convenient analytical form. An empirical formula was suggested on the basis of the modified Kohlrausch equation for the concentration dependence of the conductivity of organic electrolytes in the vicinity of a maximum. The accuracy of this equation was checked on solutions of LiBF4 in propylene carbonate; LiClO4 in ethylene carbonate; and LiPF6 in ethylene carbonate/diethyl carbonate (1: 1), ethylene carbonate/ethylmethyl carbonate (1: 1), and ethylene carbonate/methyl acetate (1: 1) at different temperatures. The calculated data are in good agreement with experiment for all the systems. The new empirical formula allows the determination of the maximum conductivity of organic electrolytes based on a few points with good accuracy, which is very important in choosing the electrolyte salt concentration in practice.  相似文献   
8.
Russian Physics Journal - Effect of ultrasonic treatment on the molecular parameters of polymeric additives based on polyalkyl acrylate is investigated. The viscosity, temperature, and energy...  相似文献   
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