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41.
42.
B. G. Zakharov 《JETP Letters》1996,64(11):781-787
A rigorous evaluation of the Landau-Pomeranchuk-Migdal effect for finite-size targets is performed within the path integral approach previously developed by the author [B. G. Zakharov, JETP Lett. 63, 952 (1996)]. The bremsstrahlung rate in QED is expressed through a solution of a two-dimensional Schrödinger equation with an imaginary potential. The boundary condition for this solution is formulated in terms of a product of the light-cone electron-photon wave function and the dipole cross section for scattering of an e + e ? pair off an atom. Numerical calculations are performed for homogeneous and structured targets. Our predictions for the homogeneous target agree well with the photon spectrum measured recently at SLAC with 25-GeV electrons. The spectra obtained for the structured, two-segment targets exhibit interference minima and maxima. 相似文献
43.
44.
A. V. Garbar M. R. Leonov L. N. Zakharov Yu. T. Struchkov 《Russian Chemical Bulletin》1996,45(2):451-454
A new neutral -arene complex of trivalent uranium, (6-C6H5Me)U(AlCl4)3 (1), was obtained by the reductive Freidel-Crafts reaction. The crystal structure of 1 was determined by single crystal X-ray diffraction analysis. The U atom in 1 is bound to the C6H5Me group by the 6 mechanism and is linked to the three AICl4 groups through two g-CI bridges. The coordination of the U atom is a distorted pentagonal bipyramid in which the center of the arene ring is in one apical position, and the bridging Cl atoms occupy the other vertices.Translated from Izvestiva Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 469–472, February, 1996. 相似文献
45.
Goryunov E. I. Petrovskii P. V. Shcherbina T. M. Zakharov L. S. 《Russian Chemical Bulletin》2001,50(6):1085-1087
Catalytic phosphorylation of -trifluoromethylbenzyl alcohols with POCl3 taken in a ratio of 3 : 1 under particular temperature conditions afforded predominantly symmetrical tris(-trifluoromethylbenzyl) phosphates. The latter were obtained as mixtures of two diastereomers with a statistical ratio of the components. 相似文献
46.
P. A. Konstantinov T. V. Shchedrinskaya I. V. Zakharov 《Chemistry of Heterocyclic Compounds》1972,8(12):1454-1454
Selenophene-2,5-dicarboxylic acid was obtained by liquid-phase oxidation of 2,5-dimethylselenophene with molecular oxygen.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, p. 1605, December, 1972. 相似文献
47.
48.
P. B. Terent'ev V. G. Kartsev A. N. Kost L. N. Novikova V. F. Zakharov V. P. Zvolinskii 《Chemistry of Heterocyclic Compounds》1980,16(4):421-423
An analysis of the PMR spectra (using double resonance) of the isomeric 3-, 6-, 7-, and 8-methyl and 7-ethyl-5-azacinnolines, and also of 7-methyl-8-azacinno-line has shown the presence in these structures of a considerable localization of the C5-C6 and C7-C8 bonds, which has been confirmed by the results of a quantum-chemical calculation by the PPP method.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 541–543, April, 1980. 相似文献
49.
V. A. Poluboyarov V. F. Anufrienko V. A. Zakharov S. A. Sergeev S. I. Makhtarulin G. D. Bukatov 《Reaction Kinetics and Catalysis Letters》1984,26(3-4):347-351
ESR studies have revealed that in Ti–Mg catalysts after interaction with organoaluminium compounds, the Ti3+ ions formed are present mainly as TiCl3 associates. Isolated Ti3+ ions of various types are also detected. Part of titanium ions is in the divalent state and provides an ESR signal after oxidation by water to the trivalent state in the form of Ti3+ ordered by cooperative Jahn-Teller interaction.
, - , Ti3+ TiCl3. Ti3+ . Ti3+ - -.相似文献
50.
A. R. Garifzyanov G. Kh. Nuriazdanova S. V. Zakharov R. A. Cherkasov 《Russian Journal of General Chemistry》2004,74(12):1885-1889
Two-phase potentiometric titration was used to determine partition constants for a series of -aminophosphonates (RO)2P(O)CH2NR1R2 [R = Alk (C2-C5), R1, R2 = Me, Et, (CH2)5] between water and organic solvents, such as chloroform, carbon tetrachloride, toluene, octane, n-octanol, nitrobenzene, o-xylene, and cyclohexane. Correlations between the partition constants and the number of carbon atoms in substrate molecules were obtained. Solvent effects on partition constants were discussed, and solution parameters of -aminophosphonates were calculated.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 12, 2004, pp. 1998–2002.Original Russian Text Copyright © 2004 by Garifzyanov, Nuriazdanova, Zakharov, Cherkasov.This revised version was published online in April 2005 with a corrected cover date. 相似文献