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31.
For families of continuous controlled dynamic input-output processes, we obtain and discuss necessary and sufficient conditions for their differential realization in the class of quasilinear nonstationary differential equations of state in a Banach space. 相似文献
32.
A. I. Rusanov 《Colloid Journal》2016,78(1):102-108
Specific features of surfactant diffusion in micellar systems are described in terms of mobility, i.e., the limiting velocity of a particle under the action of a unit force. Micellar solutions of nonionic and ionic surfactants are analyzed. A relation is established between average surfactant mobility and the mobilities of individual particles. Although micelles have a lower mobility than monomers have, the average mobility of surfactants is shown to increase rather than decrease upon micellization. In parallel, formulas describing diffusion coefficients are derived, with part of the formulas having been available in the literature. 相似文献
33.
34.
A method has been analyzed for calculating diffusion coefficients of 1 : 1 ionic surfactants as functions of their micellar solution concentrations within the framework of the quasi-chemical variant of the law of mass action. Relations have been presented for two- (with no allowance for micelles) and three-particle interaction (with allowance for micelles) formalisms. The methods for the introduction of initial calculation parameters and the calculation scheme for an ideal mixture of monomeric ions and micelles, as well as the correction for a deviation from ideality and a change in solution viscosity, have been considered. Numerical assessments have been performed by the examples of aqueous sodium dodecyl sulfate and alkyltrimethylammonium bromide solutions. 相似文献
35.
The main achievements in the synthesis of aromatic condensation monomers and polymers containing quinoxal-2,3-diyl groups are surveyed. Two general approaches to incorporation of such groups into macromolecules are considered: (i) the synthesis of polymers with α-diketone groups (polybenzyls) followed by their polymer-analogous transformations under the influence of o-phenylenediamine and its derivatives and (ii) the synthesis of target polymers of various classes from monomers containing quinoxal-2,3-diyl groups. Particular attention is focused on the properties of the polymers of interest. 相似文献
36.
M. G. Bugaenko A. L. Rusanov E. G. Bulycheva S. A. Shevelev M. D. Dutov O. V. Serushkina A. V. Pisareva Yu. A. Dobrovol’skii 《Polymer Science Series B》2013,55(7-8):478-483
A new method for the synthesis of sulfonated polynaphthylimides has been developed on the basis of the postsulfonation of high-molecular-mass polynaphthylimides with a sulfuric acid-oleum mixture. Sulfonated polymers of this type have been obtained from the polycondensation products of 5-phenylthiophenylene-1,3-diamine with dianhydrides of 1,4,5,8-naphthalenetetracarboxylic acid and 4,4′-(1,4-phenylenedicarbonyl)-bis-naphthalene-1,8-dicarboxylic acid. It has been shown that hydrogen peroxide oxidation of sulfide bridge groups of these polymers in an acidic medium yields high-molecular-mass compounds that contain sulfonic bridge fragments and, therefore, have increased thermal stabilities and enhanced proton conductivities. 相似文献
37.
Olga M. Nazarenko Eduard B. Rusanov Alexander N. Chernega Konstantin V. Domasevitch 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(3):232-236
In poly[[bis(μ‐4,4′‐bi‐1H‐pyrazole‐κ2N2:N2′)bis(3‐carboxyadamantane‐1‐carboxylato‐κO1)cobalt(II)] dihydrate], {[Co(C12H15O4)2(C6H6N4)2]·2H2O}n, (I), the Co2+ cation lies on an inversion centre and the 4,4′‐bipyrazole (4,4′‐bpz) ligands are also situated across centres of inversion. In its non‐isomorphous cadmium analogue, {[Cd(C12H15O4)2(C6H6N4)2]·2H2O}n, (II), the Cd2+ cation lies on a twofold axis. In both compounds, the metal cations adopt an octahedral coordination, with four pyrazole N atoms in the equatorial plane [Co—N = 2.156 (2) and 2.162 (2) Å; Cd—N = 2.298 (2) and 2.321 (2) Å] and two axial carboxylate O atoms [Co—O = 2.1547 (18) Å and Cd—O = 2.347 (2) Å]. In both structures, interligand hydrogen bonding [N...O = 2.682 (3)–2.819 (3) Å] is essential for stabilization of the MN4O2 environment with its unusually high (for bulky adamantanecarboxylates) number of coordinated N‐donor co‐ligands. The compounds adopt two‐dimensional coordination connectivities and exist as square‐grid [M(4,4′‐bpz)2]n networks accommodating monodentate carboxylate ligands. The interlayer linkage is provided by hydrogen bonds from the carboxylic acid groups via the solvent water molecules [O...O = 2.565 (3) and 2.616 (3) Å] to the carboxylate groups in the next layer [O...O = 2.717 (3)–2.841 (3) Å], thereby extending the structures in the third dimension. 相似文献
38.
Svitlana O. Sotnik Artem M. Mishchenko Eduard B. Rusanov Andriy V. Kozytskiy Konstantin S. Gavrilenko Sergey V. Ryabukhin Dmitriy M. Volochnyuk Sergey V. Kolotilov 《Molecules (Basel, Switzerland)》2021,26(12)
The third generation Buchwald precatalysts Pd(ABP)(Phos)(OMs) (also known as Phos Pd G3)) with XPhos and RuPhos were prepared in multigram scale by a modified procedure (ABP = fragment of C-deprotonated 2-aminobiphenyl, XPhos = 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl, RuPhos = 2-dicyclohexylphosphino-2′,6′-diisopropoxybiphenyl, OMs− = CH3SO3−). The 1H- and 31P-NMR spectra of the title complexes and some impurities, measured by various 1D and 2D techniques, were analyzed in detail. The solvent-dependent isomerization of Pd(ABP)(XPhos)(OMs) was studied by NMR, and the X-ray structures of two isomers were determined. The impurities in precatalysts, such as Pd(ABP)(HABP)(OMs) (HABP—neutral 2-aminobiphenyl coordinated to Pd2+ in N-monodentate mode) and PdCl2(XPhos)2, were identified and characterized by single crystal X-ray diffraction. A simple method for the quick quality control (QC) of the precatalysts, suitable for routine use, was proposed. The method was based on the assessment of the impurity content on the basis of the 1H-NMR spectra analysis. 相似文献
39.
Colloid Journal - Protomicelles represent a new concept of colloid science relevant to micelle-like aggregates of surfactants in solutions. In contrast to ordinary micelles, their formation... 相似文献
40.
Ruslan I. Vaskevych Alla I. Vaskevych Eduard B. Rusanov Oksana Ya. Mel'nyk Mykhailo V. Vovk 《Journal of heterocyclic chemistry》2020,57(8):3202-3212
Selective iodocyclization of 6-(alkenylamino)-1-allylpyrazolo[3,4-d]pyrimidines provided hydrogenated derivatives of 1-allyl-8(9)-iodomethylimidazo(pyrimido)[1,2-a]pyrazolo[4,3-e]pyrimidines which were further reacted with NaN3 at 75°С to 80°С to give a series of new-type 1,3,6-triazocines annulated with the pyrazole, pyrimidine, imidazole (or pyrimidine), and 1,2,3-triazole rings. The compounds synthesized were structurally characterized by analytical, spectral (IR, 1H and 13C NMR, HPLC-mass), and X-ray diffraction data. 相似文献