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991.
992.
L. A. Shchukina R. G. Vdovina Yu. B. Shvetsov A. V. Karpova 《Russian Chemical Bulletin》1962,11(2):286-288
Summary A preparative method was developed for obtaining L-and D-2-hydroxy-3-methylbutyric acids by the separation of racemic 2-hydroxy-3-methylbutyric acid with the aid of D-and L-threo-2-amino-1-p-nitrophenyl-1,3-propanediols. 相似文献
993.
L. S. Andreeva A. A. Andrianov V. E. Bel'skii M. F. Vavilova É. A. Gurylev K. V. Nikonorov 《Russian Chemical Bulletin》1971,20(10):2219-2221
Conclusions The hydrolysis of chloroacetophos in water includes the parallel cleavage of acetic acid, hydrochloric acid and methanol. The ratio of the products, formed in the parallel steps, was determined, and we also determined the total rate constant for the hydrolysis of chloroacetophos.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2336–2338, October, 1971. 相似文献
994.
995.
A. N. Dmitrievskii A. A. Pribylov N. A. Skibitskaya L. A. Zekel’ A. P. Kubyshkin M. Ya. Shpirt 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(7):1099-1104
Isotherms of sorption of butane, propane, ethane, methane, and carbon dioxide on an asphaltene sample of known elemental composition were measured. The effect of the pressure and temperature on the shape the sorption isotherms for all the adsorption systems studied was examined. The values of the initial heat of sorption were determined and compared to the energies of interaction of the molecules with asphaltene. The results obtained suggest that asphaltene is a swellable amorphous sorbent. 相似文献
996.
Powder X-ray diffraction study of sodium salts of 1-hydroxyethane-1'1-diphosphonic acid (H4L)of the compositions NaH3L·H2O, Na2H2L·4H2O, Na3HL·5.5H2O showed that these compounds aresingle-phase. Some of their properties were determined. The possibility of preparing salts of other compositionswas examined. 相似文献
997.
998.
E. Ruckenstein 《Chemical physics letters》1978,57(4):517-521
The adsorption of surfactant and cosurfactant on the surface of the globules decreases the interfacial tension between oil and water to very low values. In addition, the decrease of the bulk concentrations of the surfactant and cosurfactant decreases their chemical potential both in the bulk and at the interface, thus decreasing the free energy of the system (dilution effect). The thermodynamic stability of microemulsions is due to the fact that the total free energy change caused by these effects can become negative. The theory can explain the occurence of stable microemulsions for both non-ionic and ionic surfactants. 相似文献
999.
L. A. Aslanov V. M. Ionov V. I. Andrianov Z. Sh. Safina A. Yu. Shashkov 《Chemistry of Heterocyclic Compounds》1977,13(12):1299-1303
The crystal and molecular structures of 2,10-diacetoxy-13-thiabicyclo[7.3.1]-cis-tridec-5-ene and 2,9-dichloro-13-thiablcyclo[8.2.1]-cis-tridec-5-ene sulfoxide were established. The conformations of the molecules are such that the unshared pairs of electrons of the sulfur atoms are directed to the carboncarbon double bonds of their molecules. It was observed that there are stereochemical conditions for transannular transformations under the influence of polarized molecules and cations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1628–1632, December, 1977. 相似文献
1000.