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21.
S. M. Kostritskii Yu. N. Korkishko V. A. Fedorov M. V. Proyaeva E. A. Baranov 《Technical Physics》2002,47(1):74-79
A change in the spontaneous polarization and the nonlinear susceptibility in H: LiNbO3 waveguides is calculated from experimental data for the shift of the fundamental absorption for variously polarized rays and from IR reflection data in the range of NbO6 octahedron vibrations. It is shown that taking into account the lattice disorder provides good agreement between the theory and experiment. 相似文献
22.
E. E. Sergeev P. V. Fabinskii B. V. Polyakov V. A. Fedorov 《Russian Journal of Inorganic Chemistry》2006,51(4):687-690
The solubility of acetoacetylferrocene and 1,1′-bis(acetoacetyl)ferrocene in water and aqueous ethanol at various temperatures is studied over a wide solvent composition range. The solubilities of both compounds increase as the temperature or ethanol concentration is raised, particularly in the case of acetoacetylferrocene. The dissolution of both β-diketones is accompanied by positive changes in enthalpy and entropy. 相似文献
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B. S. Fedorov M. A. Fadeev V. V. Arakcheeva G. V. Strukov N. I. Golovina R. F. Trofimova G. V. Shilov L. O. Atovmyan 《Russian Chemical Bulletin》1994,43(12):2087-2090
A novel heterocyclic compound, 4-acetoxy-5,6-dihydro-5,5-dinitro-2H-1,3-oxazineN-oxide, has been synthesized by the reaction of the dipotassium salt of 1,1,5,5-tetranitro-3-oxapentane with aqueous acetic acid. The synthesized compound has been studied by X-ray diffraction analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2207–2210, December, 1994.We would like to thank G. V. Lagodzinskaya (Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences) for recording and interpreting1H NMR spectra, A. M. Korolev (Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences) for helpful discussion, and V. I. Fetisov (Institute of Physiologically Active Compounds, Russian Academy of Sciences) for performing quantum-chemical calculations by the AM1 SCF MO LCAO method. 相似文献
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28.
Kanitskaya L. V. Elokhina V. N. Fedorov S. V. Shulunova A. M. Nakhmanovich A. S. Turchaninov V. K. Lopyrev V. A. 《Russian Journal of General Chemistry》2002,72(5):778-784
Pyridine was reacted with propargyl bromide to obtain the dibromide [C5H5NCH = CHCH = CHCH = CHC5H5N]2
+ 2Br-. The effect of the vinyl group on its UV spectrum is qualitatively interpreted using the results of nonempirical quantum-chemical calculations (basis HF/6-31G*). 相似文献
29.
N. I. Polezhaeva I. V. Polezhaeva V. A. Levdanskii V. A. Fedorov 《Russian Journal of Applied Chemistry》2006,79(9):1559-1560
Thermal oxidative degradation of a composition based on a polyester resin modified with rosin and tetramethylammonium chloride and its use as a flux for low-temperature solder pastes were studied. 相似文献
30.
S. I. Fedorov 《Journal of Mathematical Sciences》1987,38(4):2142-2147
One considers the problem of the maximum of the product of powers of conformal radii of nonoverlapping domains in the following formulation. Let A=a1, ..., an and B=(b1, ..., bm be systems of distinguished points in ¯C and let ={1,..., m} be a system of positive numbers. ByU(D,b
) we denote the reduced modulus of the simply connected domain D relative to the pointb
D. Find the maximum of the sum
in the familyD of all systems of nonoverlapping simply connected domains Dj, j=1, ..., m, satisfying the following condition: the domain Dj does not contain points bi B, different from bj, and some collection Aj, for each domain, of points from A,
j=1
m
A
j
=A. The solution of this problem is obtained by the simultaneous use of the method of variation and of the method of the moduli of families of curves and is given by Theorem 1 of the present paper. As consequences of Theorem 1 one obtains Theorems 2 and 3, strengthening the corresponding results of a previous paper of the author.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 144, pp. 149–154, 1985. 相似文献