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21.
Conclusions Both the extent of C2H4 hydropolymerization, initiated by 0.01% CO, on Co zeolites at a temperature below 100°C, and the initiating effect increase symbatically with increase in the ratio of SiO2/Al2O3 in the zeolite in the investigated limits (from 2 to 10).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 894–896, April, 1974. 相似文献
22.
23.
Axially disymmetric tertiary amines or quaternary ammonium salts are synthesized by double alkylation of primary or secondary amines with racemic or optically pure 2,2′-bis (bromomethyl)-1,1′-binaphthyl. Their reductive cleavage by lithium aluminium hydride in refluxing THF leads to chiral secondary or tertiary amines , substituted by a binaphthyl unit, with high yields and absence of racemization. 相似文献
24.
R. G. Mirzoyan S. M. Saakyan P. B. Terent'ev K. A. Éliazyan V. V. Dovlatyan 《Chemistry of Heterocyclic Compounds》1982,18(9):983-985
Intense [M-Cl]+ and [M-CT2=CCNCl]+ ion peaks are characteristic for the mass spectra of 4-(-chloro--cyanoethylmercapto)-sym-triazines. The introduction of monoalkylamino groups into the 2 and 6 positions of the heteroring does not lead to the development of [M-HCl]+ ion peaks in the mass spectra or to a change in the characteristic fragmentation pathways.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1268–1270, September, 1982. 相似文献
25.
Physical adsorption of the title compounds on rhombic sulfur of 0.4 to 0.5 m2/g is reported. The isotherms are of type II for N2, Ar and C5H12, of type III for SO2 and CO2, and linear for SF6. There is no hysteresis. The method of Ross & Olivier shows that the surface is relatively heterogenous (γ 17). Isosteric heats of adsorption and c values of the B.E.T. equation are also reported. 相似文献
26.
Various paths for the synthesis of 4-methylamino-3-aminoveratrole (I) from 4-amino-3-nitroveratrole (II) were investigated, and it was found that I can be obtained in a high overall yield of 65% through the tosyl derivative of II. 1-Methyl-4,5-dimethoxybenzimidazolone, 1-methyl-4,5-dimethoxybenzimidazole and its 2-phenyl-, 2-chloro-, and 2-dimethylamino derivatives were synthesized on the basis of I in order to investigate their biological activity. It was established that the chemical properties of vicinally disubstituted veratrole, particularly the increased basicity of II, are determined to a significant degree by steric strains caused by bulky substituents. It is shown that 85% formic acid can be successfully used in place of 98–100% formic acid for the N-formylation of aromatic amines with a mixture of formic acid and acetic anhydride.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1387–1392, October, 1970. 相似文献
27.
Laurent Soulre Pascal Hoffmanna Frdric Bringaud 《Journal of heterocyclic chemistry》2003,40(5):943-947
N‐(p‐Nitrophenoxy)carbonyl‐3‐morpholino‐sydnonimine (NCMS) has been prepared from 3‐morpholinosydnonimine hydrochloride. Using the Griess assay and the superoxide‐mediated reduction of ferricytochrome c, the nitric oxide (NO?) and superoxide anion (O2?‐) ‐ releasing properties in phosphate buffer pH 7.4 of this novel peroxynitrite donor was studied and compared with the known 3‐morpholino‐sydnonimine (SIN‐1). From compound NCMS, a series of N‐substituted sydnonimine derivatives were easily prepared that contain purine or melaminophenyl groups which specify a recognition by a trypanosomal purine transporter. The ability of these new sydnonimines to inhibit the uptake of [23H]adenosine on Trypanosoma equiperdum was studied. 相似文献
28.
M. V. Éndzhirgli 《Ukrainian Mathematical Journal》1991,43(12):1515-1523
Under the conditions guaranteeing the uniform convergence of the spectral representations, we obtain estimates for the distribution of its supremum. We obtain estimates for the supremum of a real stationary process for which the corresponding spectral processes belong to the space
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 43, No.12, pp. 1628–1637, December, 1991. 相似文献
29.
V. P. Germogenov O. M. Ivleva S. V. Ponomarev L. S. Khludkova L. E. Épiktetova 《Russian Physics Journal》1992,35(1):20-26
The manganese doping of In1–xGaxAsyP1-y(0 y 1) films grown by liquid-phase epitaxy has been investigated. A study has been made of the influence of the solid-solution composition and of the method of introducing the manganese into the solution melt on the electrical properties of the films, and also on the surface morphology, the optical absorption edge, and the mismatch of the film and substrate lattice constants. It is shown that the hole density in the films decreases with decreasing y. The reasons for this are the decrease in the distribution coefficient of the acceptor manganese (from 0.3 to 0.001), the increase in the degree of compensation of the acceptors with donors (from 0.2 to 0.9), and the increase in the acceptor ionization energy. The composition of the InGaAsP:Mn film and the morphology of its surface depend on the method of preparation of the melt, this being explained by the strong interaction of the manganese atoms with the other components of the liquid phase.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 26–34, January, 1992.We thank T. G. Druzhinin, Ya. I. Otman, and V. B. Yabzhanov for helping with the experiments. 相似文献
30.
The reaction of 9,10-dimethylacridinium methosulfate with aromatic o-hydroxy aldehydes in alcohol in the presence of piperidine gives 10-methyl-4-(10-methyl-9-acridanylidenemethyl)-spiro[acridan-9,2-chromans]. The structure of the compounds obtained was established by means of the PMR, UV, and IR spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 539–544, April, 1973. 相似文献