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911.
N. V. Bubnov E. S. Denislamova Z. G. Aliev A. N. Maslivets 《Russian Journal of Organic Chemistry》2011,47(4):523-526
Methyl 1-aryl-3-aroyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with 1,3-diphenylguanidine to give the corresponding 6-aryl-9-aroyl-8-hydroxy-2-imino-1,3-diphenyl-1,3,6-triazaspiro[4.4]non-8-ene-4,7-diones.
The molecular and crystalline structures of 9-benzoyl-8-hydroxy-2-imino-6-(4-methylphenyl)-1,3-diphenyl-1,3,6-triazaspiro[4.4]non-8-ene-4,7-dione
were determined by X-ray analysis. 相似文献
912.
In a Hilbert space H, we study the solvability of boundary value problems for second-order elliptic differential-operator equations with a spectral parameter and with a discontinuous (piecewise constant) coefficient at the highest derivative. At the point of discontinuity, we find a transmission condition, which contains a linear unbounded operator. We present an application of the results to elliptic boundary value problems. 相似文献
913.
914.
I. I. Aliev G. Z. Dzhafarova F. I. Ismailov Dzh. A. Veliyev 《Russian Journal of Inorganic Chemistry》2013,58(2):216-218
The interaction character of the InS-Sb2Te3 system was studied by differential thermal analysis, X-ray powder diffraction, microstructure examinations, microhardness measurements, and density determinations, and its phase diagram was constructed. The InS-Sb2Te3 phase diagram is a partially non-quasi-binary section of the In,Sb∥S,Te ternary reciprocal system. Two compounds are formed in the InS-Sb2Te3 system, namely: In3Sb2S3Te3 and InSb2Te3S. Sb2Te3-based solid solutions at room temperature have an extent of up to 6 mol % InS, while InS-based solid solutions are virtually nonexistent. 相似文献
915.
E. E. Stepanova Z. G. Aliev A. N. Maslivets 《Russian Journal of Organic Chemistry》2013,49(12):1762-1767
3-Aroyl-1H-pyrrolo[2,1-c][1,4]benzoxazine-1,2,4-triones reacted with alkyl vinyl ethers according to the [4 + 2]-cycloaddition pattern with formation of substituted (1S*,16R*)- and (1R*,16R*)-16-alkoxy-14-aryl-3,15-dioxa-10-azatetracyclo[8.7.0.01,13.04,9]heptadeca-4,6,8,13-tetraene-2,11,12-triones. The structure of (1S*,16R*)-7-chloro-16-ethoxy-14-phenyl-3,15-dioxa-10-azatetracyclo[8.7.0.01,13.04,9]heptadeca-4,6,8,13-tetraene-2,11,12-trione was determined by X-ray analysis. A new synthetic approach was developed to heteroanalogs of 13(14→8)-abeo steroids, substituted 3,15-dioxa-10-azatetracyclo[8.7.0.01,13.04,9]heptadecanes. 相似文献
916.
D. M. Babanly Z. S. Aliev F. Ya. Dhafarli M. B. Babanly 《Russian Journal of Inorganic Chemistry》2011,56(3):442-449
The Tl-Te-Cl system was studied in the Tl-TlCl-Te composition region by differential thermal analysis, X-ray powder diffraction, and emf and microhardness measurements. A series of polythermal sections, an isothermal section at 400 K, and a projection of the liquidus surface of the phase diagram were constructed. The ternary compound Tl5Te2Cl characterized by a wide homogeneity region and incongruent melting by a syntectic reaction at 708 K was shown to exist. This compound was found to crystallize in tetragonal lattice (space group I4/mcm) with the parameters a = 8.921 Å, c = 12.692 Å, Z = 4. Wide phase separation regions were also found in the system, including a three-phase separation region in the Tl-TlCl-Tl2Te subsystem. Regions of primary crystallization of phases, and the types and coordinates of in- and monovariant equilibria in the T-x-y diagram were determined. From emf measurement data, the standard thermodynamic functions of formation and the standard entropy were calculated for the compound Tl5Te2Cl, as follows: ?ΔG 298 0 = 355.9 ± 1.1 kJ/mol, ?ΔH 298 0 = 377.1 ± 5.0 kJ/mol, and S 298 0 = 474.1 ± 6.8 J/(mol K). 相似文献
917.
The influence of a high-amplitude high-frequency signal on the static current-voltage characteristics of commercial semiconductor
p-n junction diodes is studied experimentally. S-shaped regions are observed in the direct branches of the current-voltage characteristics over a wide frequency range, and
a bell-shaped segment is seen in the reverse branches. The value and position of the latter on the voltage axis considerably
depend on the alternating signal frequency. 相似文献
918.
Bogomolov Yu. V. Alekseev V. V. Levanova O. A. Maiorov A. G. Malakhov V. V. Yazynin S. G. Kataev A. L. Molokoedov V. S. Maksimovskaya A. A. Ruzhickiy V. I. Klenov N. V. Bakurskiy S. V. Kupriyanov M. Yu. Soloviev I. I. Abdullaev N. A. Amiraslanov I. R. Aliev Z. S. Jahangirli Z. A. Sklyadneva I. Yu. Alizade E. G. Aliyeva Y. N. Otrokov M. M. Zverev V. N. Mamedov N. T. Chulkov E. V. 《JETP Letters》2022,116(11):853-854
JETP Letters - An Erratum to this paper has been published: https://doi.org/10.1134/S0021364022380015 相似文献
919.
Yu. M. Aliev 《Bulletin of the Lebedev Physics Institute》2008,35(6):181-183
The effect of the radial density gradient on the dispersion of guided helicon mode is considered. For the parabolic density profile, the conditions under which the wave frequency is proportional to the axial wavenumber squared (ω ≈ k z 2 ) are obtained. 相似文献
920.
A differential thermal analysis ΔT
y
(T) in vacuum has been performed, and the temperature gradient ΔT
x
(T) along the Ag2Se sample during the transition α → β has been studied. It has been shown that the transitions α → α′ and β′ → β are displacive
transitions and that the transition α′ → β′ is a reconstructive transition. It has been found that the temperature gradient
along the sample during the transition α′ → β′ passes through a deep minimum due to a strong increase in the specific heat
capacity. 相似文献