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Bushmeleva A. S. Tafeenko V. A. Zakharov V. N. Lobova A. A. Aslanov Leonid A. 《Structural chemistry》2019,30(2):425-434
Structural Chemistry - Contradictory literature on the alkali-assisted exfoliation of the melon and searching for the best precursors for different heptazine derivative synthesis led us to the... 相似文献
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Leonid S. Zakharov Galina N. Molchanova Tat'yana M. Shcherbina Pavel V. Petrovskii Martin I. Kabachnik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract We have studied the phosphorylation of 1-polyfluorólkyl-2-trialkylsilylethanols (I) with phosphorus acids chlorides. 相似文献
95.
Effect of the structure of titanium–magnesium catalysts on the morphology of polyethylene produced 下载免费PDF全文
Tatiana B. Mikenas Evgeny I. Koshevoy Vladimir A. Zakharov 《Journal of polymer science. Part A, Polymer chemistry》2017,55(14):2298-2308
The structure and formation of polyethylene (PE) particles on supported titanium–magnesium catalysts having different structural characteristics (sizes of microcrystallites, mesopores, and subparticles) were studied for the first time. Scanning electron microscopy was used to identify structural elements of the polymer particles formed over such catalysts and to reveal morphological changes in the growing polymer particles when the yield was increased from approximately 0.2 g PE/g catalyst to approximately 13 kg PE/g catalyst. A relationship was found between structural characteristics of the porous catalyst particles, morphology of the nascent polymer particles, and bulk density of the polymer powder. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2298–2308 相似文献
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The main characteristics and features of the application of the solvent-borne adhesive on the basis of vinyl chloride (co)polymers for lamination of PVC profiles have been considered. 相似文献
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V. P. Zakharov O. N. Makurina E. V. Timchenko P. E. Timchenko I. A. Bratchenko S. P. Kotova 《Bulletin of the Lebedev Physics Institute》2010,37(7):222-226
The results of the study of spectral characteristics of tree crops of Samara city as a method for measuring air pollutant
concentrations. Even-age plantings of European white birch at ten points of Samara near main motorways were chosen as objects
of study. It was shown that the ratio K of the light backscattering intensities at wavelengths of 750 and 550 nm is sensitive to pollutants and insensitive to measurement
conditions. The relation between the coefficient K and the leaf chlorophyll concentration and their dependence on the total concentration of anthropogenic substances characteristic
of internal-combustion engine exhausts (CO, NO2, SO2) were experimentally determined. The carbon oxide concentration has the strongest effect on the coefficient K. This makes it possible to apply the described method tested by the example of Samara city to ecological mapping of city
territories. 相似文献
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We elaborate on the relation between perturbative and power-like corrections to short-distance sensitive QCD observables. We confront theoretical expectations with explicit perturbative calculations existing in literature. As is expected, the quadratic correction is dual to a long perturbative series and one should use one of them but not both. However, this might be true only for very long perturbative series, with number of terms needed in most cases exceeding the number of terms available. What has not been foreseen, the quartic corrections might also be dual to the perturbative series. If confirmed, this would imply a crucial modification of the dogma. We confront this quadratic correction against existing phenomenology (QCD (spectral) sum rules scales, determinations of light quark masses and of αs from τ-decay). We find no contradiction and (to some extent) better agreement with the data and with recent lattice calculations. 相似文献
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