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1.
M. A. Kudinova N. A. Derevyanko A. A. Ishchenko A. I. Tolmachev 《Chemistry of Heterocyclic Compounds》1981,17(10):989-993
Unsymmetrical 4,6-diphenylpyrylo-2-carbo- and dicarbocyanines, as well as the analogous pyridocyanines, containing 3-ethylbenzothiazolium and 1,3,3-trimethyl-3H-indolium residues and an ethylene or trimethylene bridging grouping between the position of the polymethine chain and the position of the pyrylium or pyridinium residue were synthesized. The introduction of bridging groups is generally accompanied by a bathochromic effect and intensification (in the pyrylocyanine series) or weakening (in the pyridocyanine series) of the fine structure of the absorption bands. On the basis of the deviations calculated from the centers of the absorption bands and the dependences of the vinylene shifts and the absorption band widths on the structure of the dyes it was concluded that the trimethylene bridging groups in the examined cases increase the electron-donor character of the heterocyclic residues in the dyes more markedly than the ethylene bridging groups.See [1] for Communication 13.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1327–1331, October, 1981. 相似文献
2.
V. V. Ishchenko E. I. Nosichenko O. T. Fal'kovskaya V. P. Khilya 《Chemistry of Heterocyclic Compounds》1995,31(3):276-278
The synthesis of benzodioxane derivatives of 1-benzopyrilium salts is reported and their reaction with nucleophiles is investigated.Taros Shevchenko University, Kiev 252017. Translated from Khimiya Geterotsiklicheskikb Soedinenii, No. 3, pp. 322–324, March, 1995. Original article submitted February 6, 1995. 相似文献
3.
O. Yu. Nadzhafova M. V. Drozdova E. V. Nebesnaya V. B. Ishchenko 《Journal of Analytical Chemistry》2007,62(12):1136-1142
Conditions are optimized for preparing sol-gel modified composite films based on silicon oxide and polyvinylsulfonic acid in the presence of the Tween 20 nonionic surfactant as a template for the adsorption of Fe(II) and Zn(II) phenanthrolinates. The adsorption of Zn(II), Cu(II), Mn(II), Co(II), and Ni(II) phenanthrolinates followed by their development on the surface with Rose Bengal oxyxanthene dye was studied by spectrophotometry. The variation of the pH of the solution pH and the addition of 0.01 M of EDTA enhanced the selectivity of determining Zn(II) using a film obtained under optimum conditions. The applicability of the proposed thin-film coatings to the adsorption-spectrophotometric determination of Fe(II) and Zn(II) in the ranges of 0.2–5.6 and 0.3–5.0 mg/L, respectively, was shown. The procedure was used to determine zinc in vitamin preparations, a food supplement, and an insulin preparation. The accuracy of determination was checked by atomic absorption spectrometry. The detection limit for zinc was 0.06 mg/L at a liquid phase volume of 25 mL and absorption layer thickness of 0.015 ± 0.003 mm. 相似文献
4.
G. N. Il’inich A. V. Romanenko R. I. Kvon V. B. Fenelonov V. I. Zaikovskii A. V. Ishchenko 《Kinetics and Catalysis》2007,48(1):103-115
Nitrogen-containing catalytic filamentous carbon (N-CFC) of chemical composition NC18-NC104 has been synthesized by the decomposition of pyridine (Py) from gaseous mixtures with argon or H2 at 550–800°C on Ni/Al2O3 (Ni) and Ni-Cu/Al2O3 (Ni-Cu) high-percentage catalysts. The activity of the Ni-Cu catalyst in Py decomposition in mixtures with H2 is about one order of magnitude higher than its activity in Py/Ar mixtures (more than 70 g N-CFC per metal gram in 4.5 h at 750°C), which is interpreted as arising from the nickel-catalyzed hydrogenation of Py. The formation and growth of carbon fibers occurs through the decomposition of Py (from Ar/Py mixtures) and/or Py hydrodenitrification products (from H2/Py mixtures). The carbon material has been characterized by elemental analysis, low-temperature nitrogen adsorption, high-resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS). The effect of the noncatalytic reactions of Py and its transformation products on the composition and texture of N-CFC is discussed. 相似文献
5.
Derevyanko N. A. Ishchenko A. A. Tolmachev A. I. 《Chemistry of Heterocyclic Compounds》1992,28(3):288-291
The reaction of methylamine with symmetrical 4,6,4,6-tetraphenyl-substituted 2-pyrylopolycarbocyanines, in which both a positions of the polymethine chain are linked to the positions of the heterocyclic residues by trimethylene groups, was used to synthesize the corresponding pyridopyrylocyanines. The effect of trimethylene groupings in the 2-pyridocyanines on this transformation was examined. The principles involved in the color of the synthesized pyridopyrylocyanines were studied.See [1] for Communication 29.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 345–348, March, 1992. 相似文献
6.
I. V. Kurdyukova N. A. Derevyanko A. A. Ishchenko D. D. Mysyk 《Russian Journal of General Chemistry》2012,82(4):703-719
The di-, tetra- and hexamethine merocyaninyes, the derivatives of fluorene, diphenyl 9H-fluorene-2,7-disulfonate, and bis(2,2,3,3,4,4,5,5-octafluoropentyl) 9H-fluorene-2,7-disulfonate, as well as the derivatives of the heterocycles of moderate (indolylidene and benzotiazolylidene), weak (benzo[c,d]indolylidene and 2,6-diphenylpyrane) and strong (2,6-diphenylpyridine) electron-donor properties were synthesized and their absorption spectra in solvents of different polarity were studied. The quantum-chemical analysis of electronic structure of the synthesized merocyanines was performed and the types of electronic transitions in them were found by the DFT and TDDFT methods with the B3LYP/6-31G(d,p) basis. 相似文献
7.
Epoxy resin modified with sebacic acid was synthesized. It exhibits improved elastic properties and impact resistance. 相似文献
8.
Ishchenko A. N. Afanas’eva S. A. Belov N. N. Burkin V. V. Zakharov V. M. Zykova A. I. Sammel’ A. Yu. Skosyrskii A. B. Stepanov E. Yu. Tabachenko A. N. Chupashev A. V. Ushakova O. V. Khabibullin M. V. Yugov N. T. 《Technical Physics》2020,65(6):925-934
Technical Physics - The ballistic resistance of a combined cermet material based on a high-hardness ceramic bound with an intermetallide on a high-strength metal substrate, (TiB2 + NiTi) + Ti, is... 相似文献
9.
10.
B. N. Mironov S. A. Aseev A. A. Sokolik B. N. Mavrin A. A. Timofeev A. A. Ishchenko I. V. Kochikov S. V. Chekalin E. A. Ryabov 《Journal of Experimental and Theoretical Physics》2018,126(3):422-429
The initial stage of a nanosecond discharge in gaps with a high electric field at a cathode is studied by laser methods (interferometric, shadow, schlieren methods). The studies are performed in air at atmospheric pressure. Prominence is given to studying the evolution (appearance and growth) of the plasma channels at an anode and to estimating their parameters. 相似文献