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21.
Mircho Georgiev Tatiana Popova Zhorro S. Nickolov Nikolay Goutev Georgi Georgiev Hiroatsu Matsuura 《Central European Journal of Chemistry》2004,2(4):617-626
The hypothesis that the degree of hydration of poly(oxyethylene) (POE) in aqueous solution depends on the mole ratio of water
molecules to ether oxygen atoms in the molecule has been verified by studying the isotropic Raman spectra in the O−H stretching
region for four short-chain POEs (C 1E
n
C 1 withn=1−4). Excellent coincidence of the O−H stretching Raman band for all four POEs studied in the range of mole ratio H2O/O
ether
from 25 to 0.6 was observed, thus confirming the assumption stated above. A conclusion that all ether oxygen atoms in the
POE molecule participate in hydrogen bonding with water molecules has been made. 相似文献
22.
The electron-stimulated production of molecular hydrogen (D(2), HD, and H(2)) from amorphous solid water (ASW) deposited on Pt(111) is investigated. Experiments with isotopically layered films of H(2)O and D(2)O are used to profile the spatial distribution of the electron-stimulated reactions leading to hydrogen within the water films. The molecular hydrogen yield has two components that have distinct reaction kinetics due to reactions that occur at the ASW/Pt interface and the ASW/vacuum interface, but not in the bulk. However, the molecular hydrogen yield as a function of the ASW film thickness in both pure and isotopically layered films indicates that the energy for the reactions is absorbed in the bulk of the films and electronic excitations migrate to the interfaces where they drive the reactions. 相似文献
23.
Vladimir V. Loza Nikolay S. Vostrikov Mansur S. Miftakhov 《Mendeleev Communications》2012,22(3):125-126
Racemic monoprotected at primary hydroxy group Corey lactones were resolved using (1S,2R,5R)-6,6-dimethyl-4-oxo-3-oxabicyclo-[3.1.0]hexan-2-ol as a chiral auxiliary reagent of hemiacylal chemotype. 相似文献
24.
Asanbaeva Nargiz B. Rychkov Denis A. Tyapkin Pavel Yu. Arkhipov Sergey G. Uvarov Nikolay F. 《Structural chemistry》2021,32(3):1261-1267
Structural Chemistry - The crystal and molecular structure of tris(tetrabutylammonium) pentanitratoplumbate(II) was determined and characterized by single-crystal and powder X-ray diffraction and... 相似文献
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In this paper we give a simple proof of an inequality for intermediate Diophantine exponents obtained recently by W.M. Schmidt and L. Summerer. 相似文献
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The development of theoretical ideas on the cause and the mechanism of the change of activity coefficients is the main aim of the investigation. The model describing the interaction of hydrated ions in electrolytes is proposed. In the model the electrostatic forces between ions and change of the energy of the hydrate shell in the process of ion convergence determine ions distribution in solution. The significant factor is the dependence of dielectric permittivity on the concentration of the electrolyte and on the distance to ion. The statistical approach developed allows one to calculate the influence of principal physical factors and, on this basis, to explain the nature of curves describing the activity coefficients. The results of simulation have been tested on a large number of experimental data. 相似文献
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Nonexistence of global solutions to new ordinary differential inequality and applications to nonlineardispersive equations 下载免费PDF全文
Nikolay Kutev Natalia Kolkovska Milena Dimova 《Mathematical Methods in the Applied Sciences》2016,39(9):2287-2297
A new ordinary differential inequality without global solutions is proposed. Comparison with similar differential inequalities in the well‐known concavity method is performed. As an application, finite time blow up of the solutions to nonlinear Klein–Gordon equation and generalized Boussinesq equation is proven. The initial energy is arbitrary high positive. The structural conditions on the initial data generalize the assumptions used in the literature for the time being. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献