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1.
A method of solving the problem of sound radiation from a plate with elements of different thickness in its plane is proposed, and the results obtained with this method are presented. It is shown that the main sources of sound radiation are the inhomogeneous flexural fields formed in the elements on both sides of their joint. 相似文献
2.
Three types of transparency of a semiconductor superlattice, namely, self-induced, induced, and selective transparency, were studied. The conditions of their existence and the causes of their destruction were revealed. It was shown that the state of self-induced transparency, which is unstable in a harmonic field, can be stable in a biharmonic field. 相似文献
3.
R. A. Kotel’nikova G. N. Bogdanov G. V. Zotina V. S. Romanova Z. N. Parnes 《Physics of the Solid State》2002,44(3):576-577
Efficient quenching of eosin phosphorescence by amino-acid derivatives of fullerene (AADFs) such as C60-alanine and C60-glycine in aqueous solutions indicates the possibility of transferring electrons from eosin to fullerene upon collisions or in the exciplex state. To investigate electron transfer in the protein structure, we studied the process of incorporation of C60-alanine and C60-glycine into the heme pocket of myoglobin by controlling Förster quenching. The dissociation constant for the protein-AADF complex was estimated. 相似文献
4.
A. A. Lamberov E. V. Dement’eva Kh. Kh. Gil’manov S. R. Egorova N. V. Romanova 《Russian Journal of Applied Chemistry》2006,79(9):1453-1457
The effect of the paste molding pressure on the physicomechanical and texture characteristics of catalysts was studied. An indirect criterion is suggested to evaluate the molding pressure in industrial extruders, whose optimal value ensures good physicomechanical properties of the catalysts and kinetic control over the catalyzed reaction. The results obtained were verified in paste molding on various industrial extruders, and this enabled the optimal choice of the molding equipment. 相似文献
5.
L. T. Eremenko L. B. Romanova M. E. Ivanova I. L. Eremenko S. E. Nefedov Yu. T. Struchkov 《Russian Chemical Bulletin》1994,43(4):619-623
An effective method of esterification of 1,4-cubanedicarboxylic acid with alkylsulfuric acids is proposed. The derivatives of alkanols with substantially different pKa Valus are obtained in high yields. Molecular structures of the esters obtained are confirmed by various methods. The X-ray study showed a remarkable effect of the nature of an alkyl radical on the geometry of the cubane core.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp.668–672, April, 1994.The authors thank Dr. G. V. Lagodzinskaya for analyzing the NMR spectra and for useful discussions. 相似文献
6.
I. P. Romanova S. G. Fattakhov A. A. Nafikova I. I. Vandyukova R. R. Shagidullin N. M. Azancheev V. S. Reznik O. G. Sinyáshin 《Russian Chemical Bulletin》1998,47(9):1812-1819
The reactions of phosphine derivatives of diallyl isocyanurates with palladium(ii) dichloride lead to the formation of complexes, whose structure, composition, and stability depend on the length of the methylene
chain between the isocyanurate and diphenylphosphine fragments in the ligand. 1,3-Diallyl-5-[5′-(diphenylphosphino)pentyl
and 10′-(diphenyl-phosphino)decyl] isocyanurates with PdCl2 form monomeric L2PdCl2
trans-complexes in which P atoms of the ligands participate in coordination with the metal. 1,3-Diallyl-5-[2′-(diphenylphosphino)ethyl]
isocyanurate with PdCl2 forms a dimeric (LPdCl2)2 complex, which decomposes in a solution to the monomer including solvent molecule into the coordination sphere of the metal.
The reactions of 1,3-diallyl-5-[4′-(diphenylphosphino)butyl] isocyanurate and 1,3-diallyl-5-[6′-(diphenylphosphino)hexyl]
isocyanurate with PdCl2 give monomeric chelate LPdCl2 complexes in which one of the allyl groups of the isocyanurate cycle participates in coordination with the central ion along
with the phosphorus atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1859–1865, September, 1998. 相似文献
7.
B. A. Arbuzov O. A. Erastov I. P. Romanova Yu. Ya. Efremov R. Z. Musin 《Russian Chemical Bulletin》1982,31(2):399-401
Conclusions The reaction of o-phenylenediamine with either one or two moles of dihydroxymethylphenylphosphine gives respectively either 3-phenyl-6,7-benzo-1,5-diaza-3-phosphepane or 9,10-benzo-3,7-diphenyl-1,5-diaza-3,7-diphosphabicyclo[3.3.2]decane.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 440–443, February, 1982. 相似文献
8.
Krasnov P. O. Kuzubov A. A. Romanova T. A. Avramov P. V. 《Russian Journal of Coordination Chemistry》2004,30(9):634-638
The geometry and the electronic structure of iron porphyrinate complexes with various heterocyclic molecules in the fifth coordination position and a CO molecule in the sixth position were studied by density functional theory calculations. In the series of complexes with furan, imidazole, and pyrimidine, the bond between the Fe atom and CO is weakened due to the decrease in the overlap of the corresponding AOs. 相似文献
9.
Romanova I. V. Farbun I. A. Aleksandrova V. S. Khainakov S. A. 《Russian Journal of Applied Chemistry》2003,76(5):731-735
Composite sorbents based on Zr(IV) phosphate-hydroxyethylidenediphosphonate with different phosphate-phosphonate ratio were prepared. These sorbents were characterized by elemental analysis, X-ray diffraction, and IR spectroscopy, and their ion-exchange sorption capacity for several transition metals and strontium was studied. The sorption capacity of these sorbents increases with increasing pH. 相似文献
10.
O. N. Chupakhin S. K. Kotovskaya S. A. Romanova V. N. Charushin 《Russian Journal of Organic Chemistry》2004,40(8):1167-1174
Features of 5(6)-fluoro-6(5)-X-benzofuroxans tautomerism were investigated. By 1H, 13C, and 19F NMR spectroscopy the direction of Boulton-Katritzky rearrangement in nitration, nitrosation, and azo coupling of fluorine-containing furoxanes was determined. 相似文献