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1.
V. P. Gromov 《Mathematical Notes》2007,82(1-2):165-173
The present paper is devoted to the Cauchy problem of inhomogeneous convolution equations of a fairly general nature. To solve the problems posed here, we apply the operator method proposed in some earlier papers by the author. The solutions of the problems under consideration are found using an effective method in the form of well-convergent vector-valued power series. The proposed method ensures the continuity of the obtained solutions with respect to the initial data and the inhomogeneous term of the equation. 相似文献
2.
3.
Alkyl- and dialkylanilines are formed by the action of primary and secondary amines on nitropyridinium salts. An alkylamino or dialkylamino group is included in the final product in the step involving the open form. Aqueous methylamine may lead to opening of the ring of nonquaternized nitropyridines with subsequent formation of the benzene ring of alkylanilines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 98–102, January, 1979. 相似文献
4.
Alexei Yu. Lukin Sergei V. Shevyakov Alexei V. Laptev Olga I. Davydova Vitali I. Shvets Olga V. Demina Yury P. Strokach Valery A. Barachevsky Michail V. Alfimov Sergei P. Gromov Artem I. Vedernikov Johan Lugtenburg Andrey A. Khodonov 《Journal of inclusion phenomena and macrocyclic chemistry》2004,49(1-2):153-161
An effective synthetic approach to the preparation of a new crown-ether vinylogs involving the Horner–Emmons olefination of carbonyl precursors with the use of C2- and C5-phosphonates was proposed. The effects of the conjugation chain length and the nature of the terminal polar functions in the phosphonate reagent on the yield and process stereoselectivity were discussed. 相似文献
5.
S. N. Dmitrieva N. I. Sidorenko A. I. Vedernikov L. G. Kuz’mina J. A. K. Howard T. M. Buslaeva S. P. Gromov 《Russian Chemical Bulletin》2007,56(5):993-1002
The condensation reaction of 1,2-bis(2-haloethoxy)-4-nitrobenzenes with acyclic α,ω-(oxa)alkanedithiols in the presence of
alkali metal carbonates produced a series of nitrobenzodithiacrown ethers with macrocycles of different size. The structures
of three ethers were established by X-ray diffraction. A new method was developed for the synthesis of nitrobenzomonothia-15-crown-5
ether. Nitro derivatives of benzodithiacrown ethers were tested as reagents for extraction of palladium(II), platinum(IV), and rhodium(III) from hydrochloric acid solutions. Extraction of PdII salts was found to be highly selective compared to that of PtIV and RhIII salts. Benzodithia-15-crown-5 ether is the most efficient extractant for palladium(II). Reduction of nitrobenzothiacrown ethers with hydrazine hydrate in the presence of a platinum catalyst afforded their amino
derivatives.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 958–966, May, 2007. 相似文献
6.
M. V. Alfimov S. P. Gromov O. B. Stanislavskii E. N. Ushakov O. A. Fedorova 《Russian Chemical Bulletin》1993,42(8):1385-1389
Styryl dyes containing a crown ether group and a heteroaromatic moiety with a sulfoalkylN-substituent (1a,b) undergo photocyclodimerization in acetonitrile in the presence of Mg(ClO4)2 to give only the typeA isomer of cyclobutane derivative (2a,b). The photochemical regio- and stereoselectivity of the cycloaddition is explained by self-organization of thetrans-isomers of the styryl dyes upon complexation with the Mg2+ cations into dimers with a fixed mutual arrangement of multiple bonds.For part 7, see ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1449–1452, August, 1993. 相似文献
7.
E. N. Ushakov L. G. Kuz’mina A. I. Vedernikov M. S. Kapichnikova J. A. K. Howard M. Wörner A. M. Braun M. V. Alfimov S. P. Gromov 《Russian Chemical Bulletin》2006,55(1):94-100
The structures of new butadienyl dyes of the benzothiazole series containing the dithia-15-crown-5 (2a) or dithia-18-crown-6 (2b) fragments were established by X-ray diffraction. Complexation of dyes 2a,b with Hg2+, Pb2+, Cd2+, Ag+, Zn2+, and alkaline-earth cations in aqueous-acetonitrile solutions was studied by spectrophotometry. At a high percentage of water
in solutions (P
w ≈ 50%), these dyes have a very low ability to bind Pb2+ cations (logK < 2) and virtually do not bind Cd2+, Zn2+, and alkaline-earth cations. At the same time, these dyes form stable 1: 1 complexes with Hg2+ and Ag+ cations at all P
w. The stability constants of complexes with the Ag+ cation increase with increasing P
w because the free energy of hydration of this cation is much lower than the free energy of solvation in acetonitrile. In the
P
w range from 0 to 75%, the stability constants of the complexes of dyes 2a,b with the Hg2+ cation are larger than those of the corresponding complexes with the Ag+ cation by more than four orders of magnitude.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 90–96, January, 2006. 相似文献
8.
D. G. Gromov S. A. Gavrilov E. N. Redichev A. V. Klimovitskaya R. M. Ammosov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(10):1650-1655
A method for calculating the temperature of fusion of thin films depending on their thickness was suggested. It was shown for the example of copper and nickel films that the main factors that determined a substantial decrease in the temperature of fusion of thin films compared with massive materials were the different heats of fusion of thin films, the temperature dependence of the heat of fusion, and the tendency of thin-film systems toward decreasing the absolute surface energy at the expense of decreasing the specific surface energy and surface area. The dependences of the temperature of fusion on the thickness of copper and nickel films were calculated. Fusion and dispersion processes were studied as depending on nickel film thickness on the surfaces of Al2O3 and SiO2. The calculation results obtained for copper and nickel were in close agreement with experimental data. 相似文献
9.
Macrocycle opening in derivatives of benzocrown ethers under the action of amines is affected by the nature of the heteroatoms in the macrocycle, the nature of the functional group in the benzene ring of the crown ether, and the length, branching, and number of hydrocarbon radicals at the amine nitrogen atom. A distinguishing feature of this reaction is the template effect of MeNH3
+, Me2NH2
+, Na+, and K+ ions.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 687–692, March, 1996.For Part I see Ref. 1. 相似文献
10.
Regiospecific introduction of the 2-naphthyl residue into position 4 of the pyridine ring occurs in the reactions of isoquinolinium salts with 4-methylpyridinium salts through the intermolecular transformation of the isoquinoline bicyclic system involving the methyl group of the pyridinium salt. The reaction occurs under the action of methylammonium sulfite in an aqueous medium on heating. This method provides ring transformation not only for isoquinolinium salts but even for unsubstituted isoquinoline. 相似文献