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51.
I. Sh. Mogilevskii 《Journal of Mathematical Sciences》1984,25(1):873-884
On the bounded cylindrical domain QT = x(0,T), 3, one considers the initialboundary-value problem for the system of Navier-Stokes equations in which the boundary conditions are given by an arbitrary matrix differential operator of dimension 3×4. Under certain restrictions on this operator and on the data of the problem one shows the existence of a solution in the spaces W
p
2l,l
(QT) for any finite T.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 110, pp. 105–119, 1981. 相似文献
52.
G. Sh. Guseinov 《Mathematical Notes》1978,23(2):130-136
Restoration from the generalized spectral function of the equations $$b_0 y_0 + a_0 y_1 = \lambda y_{0,} a_{n - 1} y_{n - 1} + b_n y_n + a_n y_{n + 1} = \lambda y_{n,} n = 1,2,3,...,$$ wherea n and bn are arbitrary complex numbers,a n≠ 0 (n = o, i, 2,...), λ is a complex parameter, and {P n (λ)} 0 ∞ is the required solution, is investigated. Necessary and sufficient conditions for solvability of the inverse problem are obtained, and the restoration procedure is described. 相似文献
53.
A. Sh. Sharifkanov Sh. S. Akhmedova R. A. Timirova I. S. Chanysheva E. G. Il' yasov 《Chemistry of Heterocyclic Compounds》1971,7(3):326-327
1,4-Bis(2,5-dimethyl-4-hydroxypiperidino)-2-butene and 1,4-bis(2,5-dimethyl-4-hydroxypiperidino)-2-butyne (II and III) were obtained by the action of 1,4-dibromo-2-butene and 1,4-dibromo-2-butyne on the form of 2,5-dimethyl-4-piperidol (I). The benzoates (IV and V) were obtained by acylation of II and III with benzoyl chloride.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 352–353, March, 1971. 相似文献
54.
Summary 1. The structure of the main groups of phospholipids isolated from the seed kernels of the thin-fibered cotton plant of variety S-6029 has been studied.2. The fatty-acid compositions and the position distributions of the fatty acids have been determined, and from the results the possible molecular compositions of the phosphatidylcholines, phosphatidylethanolamines, and phosphatidylinositols have been calculated.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedimenii, No. 1, pp. 22–26, January–February, 1976. 相似文献
55.
The influence of dispersity on hydrogen adsorption on Ir black and Ir/C catalysts has been studied. It is shown that supported iridium reduces the heat of hydrogen adsorption as compared to Ir black. With decreasing catalyst dispersity, the amount of weakly bound hydrogen increases, while its adsorption heat decreases on all Ir catalysts.
Ir- Ir/C-. , Ir-. C , Ir-.相似文献
56.
Conclusions 4-Methyl-3-carene, under the conditions for the reaction of olefins with I2 and Ag2O, which leads to epoxides, forms 3-acetyl-3,6,6-trimethylbicyclo[3.1.0]hexane, a ketone that is isomeric with the epoxide.Translated from Izvestiya Akademii N auk SSSR, Seriya Khimicheskaya, No. 2, pp. 454–455, February, 1982. 相似文献
57.
The short-wave cutoff boundary of the capillary wave spectrum is established. Effective thickness L b of the “bare” density profile in the interfacial layer is calculated according to experimental data on the ellipticity ratio of reflected light. The free parameters of the extended van der Waals theory of capillarity are determined. The positions of the equimolecular dividing surface and tension surface are calculated, as well as the temperature dependence of the Tolman parameter. 相似文献
58.
Yu. Sh. Goldberg I. G. Iovel M. V. Shimanskaya 《Reaction Kinetics and Catalysis Letters》1978,8(3):327-331
As shown by IR-spectroscopic studies, pyridine bases interacting with V2O5 and MoO3 supported on MgO form hydrogen bonds with surface hydroxyls and coordinate bonds with V and Mo ions. The interaction of 2,6-dimethylpyridine adsorbed on the surface with oxygen leads to the formation of 6-methylpyridine-2-carboxaldehyde, whose formyl group interacts with surface hydroxyls.
, V2O5 MoO3, MgO, V Mo. 2,6- 6--2-, OH-.相似文献
59.
I. A. Bessonova Z. Sh. Faizutdinova S. Yu. Yunusov 《Chemistry of Natural Compounds》1973,6(6):721-723
Summary Morphine, codeine, narcotine, thebaine, papaverine, protopine, xanthaline, prophyroxine, bases with mp 267 and 263°C,l-canadine, and cryptopine have been isolated from Kirghiz opium.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 711–713, November–December, 1970. 相似文献
60.
Summary 1. Osthole, oxypeucedanin, heraclenin, and oxypeucedanin hydrate have been isolated from the roots ofHippomarathrum caspium (DC) Grossh. and identified; the presence of traces of isoimperatorin, imperatorin, and umbelliferone has been established chromatographically. A substance with mp 149–150° apparently belonging to the sitosterol group has been obtained.2. Xanthotoxin has been isolated from the leaves and stems; the presence of a small amount of bergaptene and umbelliferone has been detected chromatographically.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 5, pp. 356–359, 1965 相似文献