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11.
Volkov P. A. Ivanova N. I. Telezhkin A. A. Khrapova K. O. Larina L. I. Gusarova N. K. Trofimov B. A. 《Russian Journal of General Chemistry》2019,89(1):59-62
Russian Journal of General Chemistry - Oxidative cross-coupling of 4-acetylaminophenol (paracetamol) and its structural isomers (2- and 3-acetylaminophenols) with secondary phosphine chalcogenides... 相似文献
12.
F. Kh. Inoyatov R. Sh. Abubakirov A. I. Mikaya I. M. Khrapova V. M. Perchenko N. A. Plate 《Russian Chemical Bulletin》1993,42(5):955-958
The catalytic properties of alumoxane compounds in the alkylation of 4-methoxyphenol with styrene were studied. Structures and yields of aikylation products depend on the amount of catalyst, the phenol: olefin ratio, and the reaction time. Phenoxyalumoxanes are effectiveortho-directing catalysts with respect to the hydroxy group. Under optimum conditions, 2-(-methylbenzyl)-4-methoxyphenol and 2,5-di-(-methylbenzyl)-4-methoxyphenol were obtained in 94 % and 84–86 % yields, respectively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 992–994, May, 1993. 相似文献
13.
Volkov P. A. Khrapova K. O. Bidusenko I. A. Telezhkin A. A. Schmidt E. Yu. Albanov A. I. Trofimov B. A. 《Russian Chemical Bulletin》2022,71(7):1514-1518
Russian Chemical Bulletin - Terminal secondary 4-chlorophenyl propargylamines, synthesized by addition of acetylene to N-(4-chlorophenyl)ketimines (ButOK, DMSO, 20–25 °C) in 76–93%... 相似文献
14.
Storozhok N. M. Gureeva N. V. Krysin A. P. Borisenko V. E. Rusina I. F. Khrapova N. G. Burlakova E. B. 《Kinetics and Catalysis》2004,45(4):488-496
Efficiency of the inhibiting action of phenol-based antioxidants (AO) was studied in initiated oxidation of methyl oleate (MO). The following AO were examined: hydroxybenzene (I), tyrosol (4-2-hydroxyethylphenol) (II), 2-tert-butyltyrosol (III), 2,6-di-tert-butyltyrosol (IV), 4-3-hydroxypropylphenol (V), 2,6-di-tert-butylphenol (VI), dibunol (2,6-di-tert-butyl-4-methylphenol) (VII), and -tocopherol (VIII). The rate constants k
7 determining the activity of AO in the reaction with peroxide radicals were equal to (0.94, 0.97, 0.93, 0.75, 0.92, 1.30, and 360.00) × 104 M-1 s-1 for compounds II, III, IV, V, VI, VII, VIII, respectively. For inhibitors II-VI, VIII, the dependence of the induction period on the AO concentration was of an extreme character, and the most efficient concentrations of AO (C
max) were equal to (0.7, 1.0, 1.6, 1.0, 1.1, and 2.5) × 10-3 M, respectively. The efficiency of inhibitors (max and C
max) was demonstrated to rise with increasing extent of shielding of the OH group and shortening of the chain of a substituent in the para position. Using the stationary photolysis method, the rate constants of disproportionation (k
9) of phenoxy radicals of inhibitors I, III, VII, and VIII were evaluated and equal to (0.52, 2.38, 3.40, and 0.94) × 103 M-1 s-1, respectively, at 20°C. It was shown that the k
9 value depended on the extent of shielding of phenoxy radicals. The rate constants (k
10, eff) were determined for the reaction of phenoxy radicals with lipids with various extents of unsaturation: MO, linoleic and arachidonic acids. The values of k
10, eff for the reaction of phenoxy radicals of I, III, VII, and VIII with linoleic acid (20°C) were equal to (0.69, 0.48, 0.09, and 0.49) × 102 M-1 s-1, respectively. It was found that in MO oxidation, the k
10, eff values decreased in proportion to the number of ortho-tert-butyl substituents in an AO molecule. For the reactions of phenoxy radicals of inhibitor VII with MO, linoleic and arachidonic acids, the values of k
10, eff increased with the number of double bonds in a substrate and were equal to (0.09 ± 0.01, 0.09 ± 0.01, and 0.64 ± 0.04) × 102 M-1 s-1, respectively. The k
10, eff rate constants for the reaction of phenoxy radicals of compound VIII with the same lipids were equal to (0.20 ± 0.04, 0.49 ± 0.01, and 0.74 ± 0.12) × 102 M-1 s-1, respectively. 相似文献
15.
Andrei A. Krasilin Maksim M. Khalisov Ekaterina K. Khrapova Tatyana S. Kunkel Daniil A. Kozlov Nikolay M. Anuchin Andrey N. Enyashin Alexander V. Ankudinov 《Particle & Particle Systems Characterization》2021,38(12):2100153
Some phyllosilicate compounds have the ability of spontaneous scrolling because of the size mismatch between the covalently bounded metal oxide and silica sheets. Their unique structure and high theoretically predicted Young's modulus (around 210–230 GPa) induce phyllosilicates’ application as reinforcing fillers. However, previous nanomechanical experiments with individual phyllosilicate nanoscrolls are in poor agreement with theory. The main reason for this is the low accuracy of experiments, which leads to large measurement errors compared to measured average values. Here, the study of the mechanical properties of synthetic (Mg1–xNix)3Si2O5(OH)4 phyllosilicates is reported by testing a suspended nanoobject (a nanobridge) with an atomic force microscope (AFM). The Young's modulus of corresponding phyllosilicate model layers is also calculated by means of the density functional theory (DFT). The original AFM approach makes it possible to account for the probe slipping off the nanobridge and determine its boundary conditions. The measured Young's modulus values are considered within the models of surface tension and shear strain contributions. The shear strain appears to have a decisive impact on the measured Young's modulus (from 150 ± 70 GPa to 200 ± 210 GPa) and its spread. 相似文献
16.
Dr. Andrei A. Krasilin Ekaterina K. Khrapova Dr. Alexandre Nominé Dr. Jaafar Ghanbaja Prof. Thierry Belmonte Prof. Victor V. Gusarov 《Chemphyschem》2019,20(5):719-726
Here, we study the stress-induced self-organization of Mg2+ and Ni2+ cations in the crystal structure of multiwalled (Mg1–x,Nix)3Si2O5(OH)4 phyllosilicate nanoscrolls. The phyllosilicate layer strives to compensate size and surface energy difference between the metal oxide and silica sheets by curling. But as soon as the layer grows, the scrolling mechanism becomes a spent force. An energy model proposes secondary compensation of strain: two cations distribute along the nanoscroll spiral in accordance with preferable radii of curvature. To reveal this, we study synthetic (Mg1–x,Nix)3Si2O5(OH)4 nanoscrolls by the scanning transmission electron microscopy/energy-dispersive X-ray spectroscopy (STEM/EDS) technique. For a number of scrolls, we have found indeed a change of Ni concentration with increase in distance from the nanoscroll central axis. The concentration gradient, according to our estimates, can reach 50 at.% over 25 nm of the wall thickness. 相似文献
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Boris A. Trofimov Nina K. Gusarova Pavel . Volkov Nina I. Ivanova Kseniya O. Khrapova 《Heteroatom Chemistry》2016,27(1):44-47
Oxidative cross‐coupling between secondary phosphine chalcogenides and alcohols or phenols proceeds in CCl4 medium at 80–82°C to afford phosphinoсhalcogenоic O‐esters in up to 92% yield. These couplings represent first examples of the Atherton–Todd‐like reaction occurring in the absence of bases. 相似文献
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Malysheva S. F. Kuimov V. A. Belogorlova N. A. Khrapova K. O. Apartsin K. A. Gusarova N. K. 《Russian Journal of Organic Chemistry》2022,58(2):192-199
Russian Journal of Organic Chemistry - Alkylphosphinic acids, including long-chain ones, were synthesized in up to 76% yields from red phosphorus and n-AlkBr (Alk = C4–C14) under micellar... 相似文献