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61.
T. K. Goncharov V. V. Dubikhin E. L. Ignat’eva G. M. Nazin Z. G. Aliev S. M. Aldoshin 《Russian Journal of General Chemistry》2013,83(4):717-721
Structure of isoxazoline compounds formed via the reaction of alkyl-substituted benzonitrile oxides with ethylene was determined by X-ray diffraction method. Isoxazoline ring is flattened, the bond lengths in it depend slightly on the nature of substituents (CH3, C2H5) and their position in the benzene ring and the angle of rotation relative to the isoxazoline ring. The connection N-O has a length 1.422 Å. Thermal decomposition of isoxazolines in a liquid phase (160–280°C) is accompanied by the release of acetaldehyde and aromatic nitrile. Both the structure of the cycle and its stability is practically independent of the structure of an aromatic substituent. The rate constant of the initial stage is characterized by the low significance of kinetic parameters, E = 104°8 kJ mol?1 and log a(A/c) = 7.2±0.8. The results obtained are rationalized in terms of biradical mechanism of isoxazoline ring-opening that includes an efficient recombination of the biradical and its disappearance as a result of synchronous multi-center rearrangement with the release of acetaldehyde. 相似文献
62.
N. M. Tutynina N. L. Racheva V. A. Maslivets Z. G. Aliev A. N. Maslivets 《Russian Journal of Organic Chemistry》2013,49(1):95-98
3-Aroyl-1H-pyrrolo[2,1-c][1,4]benzoxazine-1,2,4-triones reacted with 5,5-dimethylcyclohexane-1,3-dione to give 3′-aroyl-4′-hydroxy-1′-(2-hydroxyphenyl)-6,6-dimethyl-6,7-dihydrospiro[1-benzofuran-3,2′-pyrrole]-2,4,5′(1′H,5H)-triones. The crystalline and molecular structures of 3′-benzoyl-4′-hydroxy-1′-(2-hydroxyphenyl)-6,6-dimethyl-6,7-dihydrospiro[1-benzofuran-3,2′-pyrrole]-2,4,5′(1′H,5H)-trione were determined by X-ray analysis. 相似文献
63.
S. M. Aldoshin Z. G. Aliev A. A. Astrat’ev T. K. Goncharov D. V. Dashko Yu. M. Milekhin A. I. Stepanov N. I. Shishov 《Journal of Structural Chemistry》2013,54(2):462-464
The crystal structure of a new energetic compound of 4,4″-dinitro-[3,3′:4,3″]-tris-[1,2,5]-oxadiazole is studied. 相似文献
64.
The effect of low-temperature annealing on the magnetization curve of YBa2Cu3O6 + x ceramics in the superconducting state (x ≈ 0.9) is investigated. When the annealing time is fairly long, the field dependence of magnetic moment M exhibits a feature in the form of a plateau, where the value of M remains almost constant. The evolution of this feature in the magnetization curves of annealed samples with annealing time and temperature is studied. It is assumed that low-temperature annealing gives rise to metastable ferromagnetic clusters in YBa2Cu3O6 + x ceramics, the contribution of which to the magnetic moment accounts for the feature in the magnetization curves of the annealed samples. 相似文献
65.
Aliev Ramiz A. Khomenko Irina A. Kormazeva Ekaterina S. 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):983-989
Journal of Radioanalytical and Nuclear Chemistry - Thin natEr2O3 targets were irradiated on cyclotron by 60 MeV alpha particles. Thulium and ytterbium radioisotopes, formed during... 相似文献
66.
We study the Cauchy problem for systems of weakly coupled Klein–Gordon equations with dissipations. We prove a theorem on the nonexistence of global solutions with positive initial energy. 相似文献
67.
Gadzhiev G. M. Gamzatov A. G. Aliev R. A. Abakarova N. S. Emiraslanova L. L. Markelova M. N. Kaul’ A. R. 《Physics of the Solid State》2020,62(5):765-769
Physics of the Solid State - The temperature–frequency spectra of the complex dielectric permittivity of the LuFe2O4 multiferroics have been studied in the temperature range 100–400 K... 相似文献
68.
Aliev A. R. Akhmedov I. R. Kakagasanov M. G. Aliev Z. A. 《Physics of the Solid State》2020,62(6):998-1010
Physics of the Solid State - Processes of molecular relaxation in Li2SO4, Na2SO4, and K2SO4 sulfates; Li2CO3, Na2CO3, and K2CO3 carbonates; NaClO4 and KClO4 perchlorates; and Ca(NO3)2, Sr(NO3)2,... 相似文献
69.
O. P. Kuznetsova D. A. Khalilov I. I. Aliev B. V. Yastrebov A. M. Vasserman E. V. Prut 《Russian Journal of Physical Chemistry B, Focus on Physics》2009,3(6):1004-1007
Spin probe EPR spectroscopy was used to study the local dynamics of vulcanizates of an ethylenepropylene-diene elastomer and
rubber powders prepared from them. It was revealed that the preparation of rubber powders is accompanied by the formation
of a polymer network with an essentially nonuniform local structure. 相似文献
70.
Abil E. Aliev Alex J. Sinclair Shen Zhou John D. Wilden Stephen Caddick Dimitri M. Kullmann Dmitri A. Rusakov 《Journal of Physical Organic Chemistry》2009,22(6):607-612
While developing a synthesis towards tagged dizocilpine (MK‐801) analogues, we observed highly restricted inversion of a nitrogen centre in a number hydroxylamines obtained as key intermediates. These compounds are shown to possess some of the structural elements which are expected to significantly hinder the nitrogen inversion, potentially leading to hydroxylamines with a chiral nitrogen centre. Free energy barriers (ΔG≠) of the nitrogen inversion were estimated to be ca. 22 kcal mol?1 at temperatures near 420 K using variable temperature NMR measurements in DMSO‐d6. Further density functional studies of a number model systems were undertaken in order to better rationalize the measured inversion barriers and follow the role of various structural factors in raising the barrier height of the nitrogen inversion process. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献