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81.
82.
Yu. M. Mamedov 《Journal of Applied Mathematics and Mechanics》1990,54(6):815-820
Reciprocity formulas are constructed and representations of the Somigliani-type are obtained for quasistatic and dynamic problems of uncoupled generalized thermoelasticity in the Lord-Shulman formulation that is effective for applications. Moreover, representations are obtained for the stresses and heat flux. Unlike the existing approach (/1/, say) these formulas are derived on the basis of an examination of the system of differential equations of the above-mentioned problems of generalized thermoelasticity as a system with appropriate non-selfadjoint differential operators. Operators adjoint to the initial differential operators are introduced into consideration for the construction of the reciprocity formulas (second Green's formula), and a Laplace transformation is used. 相似文献
83.
B. F. Gordiets Sh. S. Mamedov 《Journal of Applied Mechanics and Technical Physics》1974,15(3):297-304
Analytical expressions were derived for the vibrational distribution function in a system of anharmonic oscillators under conditions where the supply of vibrational energy considerably exceeded the equilibrium value. Distribution was found by considering the effect of vibrational-vibrational and vibrational-translational energy exchange, as well as spontaneous radiative transitions. Analytical expressions were also obtained for the relaxation rate of vibrational energy. It was shown that where there is a strong deviation from equilibrium this rate can significantly exceed the corresponding value for a model of harmonic oscillators and is determined by the probability of vibrational-vibrational exchange in the molecules. 相似文献
84.
Mamedov V. A. Khafizova E. A. Gubaidullin A. T. Murtazina A. M. Adgamova D. I. Samigullina A. I. Litvinov I. A. 《Russian Chemical Bulletin》2011,60(2):368-372
A reaction of 3-(α-aminobenzyl)quinoxalin-2(1H)-one with ethyl acetoacetate in boiling acetic acid is accompanied by contraction of the pyrazine ring. A rearrangement involving
the fragment C(2)-C(3)-C(NH2)Ph of the quinoxaline system and the fragment C(2)-C(3) of ethyl acetoacetate yields 2-(4-ethoxycarbonyl-5-methyl-2-phenylpyrrol-3-yl)benzimidazole.
Possible pathways of this reaction are considered. 相似文献
85.
Henig J Mamedov I Fouskova P Tóth É Logothetis NK Angelovski G Mayer HA 《Inorganic chemistry》2011,50(14):6472-6481
A novel class of 1,4,7,10-tetraazacyclododecane-1,4,7-tris(methylenecarboxylic) acid (DO3A)-based lanthanide complexes with relaxometric response to Ca(2+) was synthesized, and their physicochemical properties were investigated. Four macrocyclic ligands containing an alkyl-aminobis(methylenephosphonate) side chain for Ca(2+)-chelation have been studied (alkyl is propyl, butyl, pentyl, and hexyl for L(1), L(2), L(3), and L(4), respectively). Upon addition of Ca(2+), the r(1) relaxivity of their Gd(3+) complexes decreased up to 61% of the initial value for the best compounds GdL(3) and GdL(4). The relaxivity of the complexes was concentration dependent (it decreases with increasing concentration). Diffusion NMR studies on the Y(3+) analogues evidenced the formation of agglomerates at higher concentrations; the aggregation becomes even more important in the presence of Ca(2+). (31)P NMR experiments on EuL(1) and EuL(4) indicated the coordination of a phosphonate to the Ln(3+) for the ligand with a propyl chain, while phosphonate coordination was not observed for the analogue bearing a hexyl linker. Potentiometric titrations yielded protonation constants of the Gd(3+) complexes. log K(H1) values for all complexes lie between 6.12 and 7.11 whereas log K(H2) values are between 4.61 and 5.87. Luminescence emission spectra recorded on the Eu(3+) complexes confirmed the coordination of a phosphonate group to the Ln(3+) center in EuL(1). Luminescence lifetime measurements showed that Ca-induced agglomeration reduces the hydration number which is the main cause for the change in r(1). Variable temperature (17)O NMR experiments evidenced high water exchange rates on GdL(1), GdL(2), and GdL(3) comparable to that of the aqua ion. 相似文献
86.
The objective of this Letter is to provide an efficient and reliable analytical procedure for the generalized Bloch–Gruneisen function with the Debye temperatures for the wide temperature range using the binomial expansion theorems. As will be seen, the present formulation yields compact closed-form expressions which enable the ready calculation of Bloch–Gruneisen function for integer and noninteger values of parameter m. The proposed procedure guarantees the reliable application of the contribution of electron–photon interaction to the electrical resistivity of metals. Finally, the algorithm is used to simulate the variation of the resistivity and thermal conductivity against temperature sintered polycrystalline MgB2. Furthermore, the comparison of the method with numerical calculations demonstrates the applicability and accuracy of the method. 相似文献
87.
E. G. Mamedov 《Russian Journal of Organic Chemistry》2002,38(1):15-18
Effect of the conditions on the enantiomeric purity, overall yield, isomeric composition ofchiral polybromonorbornene Diels-Alder adducts of polybromocyclopentadienes and (-)-menthyl acrylatewas studied. Enantiomerically pure polybromonorbornenecarboxylic acids were obtained by resolution of the corresponding racemates through diastereoisomeric salts with l-ephedrine. The structure of the products was confirmed by the IR and 1H NMR spectra. 相似文献
88.
V. A. Mamedov I. Z. Nurkhametova S. K. Kotovskaya A. T. Gubaidullin Ya. A. Levin I. A. Litvinov V. N. Charushin 《Russian Chemical Bulletin》2004,53(11):2568-2576
A procedure was developed for the synthesis of thiazolo[3,4-a]quinoxaline derivatives based on a new strategy for construction of the pyrazine ring. The key step of the process involves the reaction of 4-hydroxy-3,5-diphenyl-2-phenyliminothiazolidines with o-phenylenediamines.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2462–2470, November, 2004. 相似文献
89.
90.
V. A. Mamedov E. A. Berdnikov V. N. Valeeva I. E. Ismaev I. Ch. Rizvanov L. A. Antokhina I. A. Nuretdinov P. P. Chernov 《Russian Chemical Bulletin》1993,42(11):1879-1882
Cyclization of thiosemicarbazide with methyl 3-chloro-2-oxo-3-phenylpropionate in MeCN results in 5-hydroxy-2-imino-5-methoxycarbonyl-6-phenylperhydro-1,3,4-thiadiazine. The structure of the product has been confirmed using spectral (IR,1H,13C,13C{1H} NMR) methods and chemical transformations.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1962–1965, November, 1993. 相似文献