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排序方式: 共有288条查询结果,搜索用时 968 毫秒
1.
Romanenko G. V. Fokin S. V. Bogomyakov A. S. Zueva E. M. Ovcharenko V. I. 《Journal of Structural Chemistry》2022,63(3):441-450
Journal of Structural Chemistry - The structures of Ni(II), Cu(II), and Zn(II) complexes with anions of 2,5-pyrrolyl-disubstituted nitronyl nitroxide (L1) and iminonitroxide (L2) diradicals (HL1 is... 相似文献
2.
Romanenko G. V. Letyagin G. A. Maryunina K. Yu. Bogomyakov A. S. Nishihara S. Inoue K. Ovcharenko V. I. 《Russian Chemical Bulletin》2020,69(8):1530-1536
Russian Chemical Bulletin - The study is concerned with structural rearrangements in the crystals of heterospin complexes Cu(hfac)2 with nitroxide radicals LR (hfac is hexafluoroacetylacetonate, LR... 相似文献
3.
The electrical conductivity of hydrosols of ultradispersed diamonds was studied. The electromembrane method for cleaning and concentrating of ultradispersed diamonds in hydrosols was considered. The influence exerted by the concentration of the dispersed phase on the electrical characteristics of the cleaning process was analyzed. A mathematical relation making it possible to evaluate the output characteristics of the process and to determine the geometrical characteristics of the apparatus was proposed. 相似文献
4.
We generalize literature data and our own experimental data on using 1,3-dipolar cycloaddition reactions for synthesis of fullerene C60 derivatives containing annelated heterocyclic moieties.M. V. Lomonosov Moscow State University, Moscow 119899, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–297, March, 1998. 相似文献
5.
V. A. Donchenko M. V. Kabanov V. T. Kalaida B. I. Kulakov E. V. Ovcharenko I. G. Sokovets 《Russian Physics Journal》1998,41(5):476-484
The problems of determining and investigating the informative parameters of atmospheric electricity are discussed. It is shown
that short-period variations in atmospheric electricity are ecologically significant. An automated system for monitoring atmospheric
electricity and a method of processing the results of measurements are described.
V. D. Kuznetsov Siberian Physicotechnical Institute, Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh
Zavedenii, Fizika, No. 5, pp. 88–98, May, 1998. 相似文献
6.
7.
Elena Yu. FursovaVictor I. Ovcharenko Galina V. RomanenkoEugene V. Tretyakov 《Tetrahedron letters》2003,44(34):6397-6399
Reduction of nitronyl nitroxides using hexamethylenetetramine is a very convenient method for preparing the corresponding imino nitroxides and 2-imidazoline N-oxides. 相似文献
8.
Spin density redistribution between the paramagnetic centers Cu2+, N-O, and N’-O’ of bischelate complexes CuL2 of the copper ion with enaminoketone 3-imidazoline nitroxides (L) are investigated using an ab initio RHF (restricted Hartree-Fock)
approach. The most important channels of unpaired electron delocalization over the systems of π- and Σ-bonds in such complexes
are revealed. The conformation dependence of spin density localized on paramagnetic centers and delocalized due to a distortion
of the structure of the environment of the Cu2+ ion from square planar to tetrahedral is analyzed and explained.
Translated fromZhurnal Strukturnoi Khimii, Vol. 38, No. 5, pp. 840–849, September-October, 1997. 相似文献
9.
V. V. Ovcharenko V. V. Lashin P. B. Terent'ev 《Chemistry of Heterocyclic Compounds》1993,29(7):844-855
This review concerns the cyclization of thiosemicarbazones and thiocarbhydrazones of carbonyl compounds leading to the title heterocycles. We examine the irreversible cyclization by the action of oxidizing agents or as the result of acylation or alkylation as well as the ring—chain tautomerism. The effect of the substitution and solvent on the equilibrium of the thiosemicarbazones with some of the possible heterocyclic tautomeric forms was examined. The usefulness of these data for predicting the results of their irreversible cyclization was discussed.Dedicated to Professor A. R. Katritzky on the occasion of his sixty-fifth birthday.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 991–1005, July, 1993. 相似文献
10.
Ovcharenko VV Pihlaja K Stájer G 《Journal of the American Society for Mass Spectrometry》2003,14(9):1049-1056
The mass spectrometric behavior of stereo- and regioisomeric, partially saturated isoindoloquinazolines was studied by positive-ion electron ionization (EI) and fast-atom bombardment (FAB/LSIMS) mass spectrometry combined with collision-induced dissociation (CID). A highly stereospecific retro-Diels-Alder process was observed in the cyclohexene-fused isomers under the EI conditions, and a corresponding (although less specific) fragmentation was observed in their FAB spectra. In the absence of RDA fragmentations, regio- and stereoisomers of the cyclohexane-fused heterocycles could be distinguished based on their FAB/CID spectra. 相似文献