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1.
A. I. Mikaya E. A. Trusova L. I. Perepelitchenko V. G. Zaikin 《Chemistry of Heterocyclic Compounds》1981,17(3):239-244
The mass spectra of cis- (Ia-c) and trans-2-methyl-4-R-thiacyclohexanes (IIa-c; a R = n-C4H9, b R = n-C5H11, c R = Ph) were studied. It was established that [M-CH3]+ ions, which correspond to the loss of a methyl group from the 2 position, are formed more readily in the case of the less stable trans isomers IIa-c than in the case of cis isomers Ia-c. The three-dimensional structures of the substances have no effect on the degree of elimination of the R substituent. The relative ionization energies (RIE) for Ia,b and IIa,b and the relative appearance energies (RAE) of the [M-CH3]+ ions were measured by the electron impact method. It was found that the RIE are almost 0.05 eV lower and that the RAE of the [M-CH3]+ ions are 0.1 eV lower for trans isomers IIa,b than for cis isomers Ia,b.Communication 4 from the series Ionization and appearance energies in organic chemistry, See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 333–338, March, 1981. 相似文献
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V. G. Zaikin E. A. Trusova L. P. Shcherbakova 《Chemistry of Heterocyclic Compounds》1978,14(2):135-140
Monosubstituted - and -alkylthiophans and -, -, and -alkylthiacyclohexanes were subjected to a comparative mass spectrometric study. The stability of the M+ ion increases on passing from - to -alkylthiophans and from - to - and -alkylthiacyclohexanes. In the case of -alkylthiophans and - and -alkylthia-cyclohexanes the principal process is associated with ejection of the substituent as a whole, whereas a portion of the alkyl substituent, with retention of one CH2 group in the composition of the charged fragment, is eliminated from the molecular ions of -alkylthiophans and -alkylthiacyclohexanes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 176–181, February, 1978. 相似文献
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S. A. Samoylenko S. E. Kichanov A. V. Belushkin D. P. Kozlenko V. M. Garamus V. S. Gurin E. A. Trusova G. P. Shevchenko S. K. Rakhmanov L. A. Bulavin B. N. Savenko 《Physics of the Solid State》2011,53(12):2431-2434
The structural aspects of the formation of Ti-Ce-O nanoclusters in silicate glasses doped with oxides TiO2 and CeO2 have been studied by means of small-angle neutron scattering. It has been obtained that, in such glasses, complex oxide nanoclusters with sizes of 300–380 Å are formed; their average size increases and the fractal dimension is changed as the concentration of the initial oxides increases. Correlation between the structural characteristics of the nanoclusters and the optical properties of the doped silicate glasses is discussed. 相似文献
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Prof. Dr. Evgeny V. Tretyakov Dr. Svetlana I. Zhivetyeva Dr. Pavel V. Petunin Dmitry E. Gorbunov Prof. Dr. Nina P. Gritsan Prof. Dr. Irina Yu. Bagryanskaya Dr. Artem S. Bogomyakov Dr. Pavel S. Postnikov Dr. Maxim S. Kazantsev Prof. Dr. Marina E. Trusova Dr. Inna K. Shundrina Dr. Elena V. Zaytseva Dr. Dmitriy A. Parkhomenko Prof. Dr. Elena G. Bagryanskaya Prof. Dr. Victor I. Ovcharenko 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20885-20891
Thermally stable organic diradicals with a triplet ground state along with large singlet-triplet energy gap have significant potential for advanced technological applications. A series of phenylene-bridged diradicals with oxoverdazyl and nitronyl nitroxide units were synthesized via a palladium-catalyzed cross-coupling reaction of iodoverdazyls with a nitronyl nitroxide-2-ide gold(I) complex with high yields. The diradicals exhibit high stability and do not decompose in an inert atmosphere up to 180 °C. For the diradicals, both substantial AF (ΔEST≈−64 cm−1) and FM (ΔEST≥25 and 100 cm−1) intramolecular exchange interactions were observed. The sign of the exchange interaction is determined both by the bridging moiety (para- or meta-phenylene) and by the type of oxoverdazyl block (C-linked or N-linked). Upon crystallization, diradicals with the triplet ground state form unique one-dimensional exchange-coupled chains with strong intra- and weak inter-diradical ferromagnetic coupling. 相似文献
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We use tools of the equilibrium statistical mechanics of disordered systems to study analytically the statistical properties of an ecosystem composed of N species interacting via random mutual interactions, as well as via deterministic self-interactions of order p>/=2. We show that the main effect of increasing the order of the interactions among the species is to make the system less competitive, in the sense that the fraction of extinct species is greatly reduced. In addition, we find that for p>2 there is a threshold value which gives a lower bound to the concentration of the surviving species, preventing then the existence of rare species and, consequently, increasing the robustness of the ecosystem to external perturbations. 相似文献
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A. M. Gromov K. N. Nesterov S. A. Pirkovskii G. V. Solodukhov V. M. Trusova 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(11):1566-1570
The results from investigating the effect of radiation exposure on the rate of chemical reactions in acid aqueous solutions
of Fe2+, which are widely used in hydrometallurgy of nonferrous metals to extract the target components into solution from ores,
are presented. The potential of the applied method is demonstrated. 相似文献
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O. I. Davydova A. V. Agafonov A. S. Kraev T. A. Trusova 《Russian Journal of Applied Chemistry》2010,83(1):14-17
The effect, which the type of the solvent, as a synthesis medium, and precursor, as a starting reagent of the synthesis, exert
on the rheological properties of the hydrolysis product, titanium dioxide, has studied. Titanium alkoxides were hydrolyzed
in a medium of isopropyl alcohol and ethanol. As hydrolysis precursors were chosen titanium isopropoxide and titanium butoxide. 相似文献
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The electrophysical properties of silicon MIS structures with ytterbium oxide as the insulator are investigated. It is established
that the electrical conductivity of the MIS structures are described by a Poole-Frenkel mechanism. The capacitance-voltage
curves are used to measure the trapped charge in the insulator and the density of surface states. The energy barriers for
electrons at the interfaces are determined by the method of internal photoemission of charge carriers into the insulator.
The parameters of deep electron traps in ytterbium oxide are investigated.
Zh. Tekh. Fiz. 69, 60–64 (April 1999) 相似文献