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Prof. Vladimir K. Cherkasov Prof. Gleb A. Abakumov Dr. Georgy K. Fukin Dr. Svetlana V. Klementyeva Dr. Viacheslav A. Kuropatov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(43):13821-13827
A new stable sterically hindered o‐quinone annelated with a 1,2‐dithiete ring was prepared by using mild conditions. The skeleton of the compound comprises diolate and dithiolate functions that have the potential to bind metals leading to the corresponding complexes. The reactivity of this compound as a ligand with respect to both coordination sites was studied. Reactions with metals indicate that the o‐quinone function is reduced in the first stage to give semiquinonate and catecholate complexes. The dithiolate coordination site was involved in the reaction in a few cases only after diolate was bound. A trinuclear manganese complex with coordination on both sites was obtained and characterized by EPR spectroscopy. The electrochemical study of this quinone fused with dithiete is reported. 相似文献
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Predrag M. Tekić Jelena B. Rađenović Svetlana S. Popović 《International Journal of Computational Fluid Dynamics》2013,27(9):383-390
In this article, the lattice Boltzmann method is employed in order to explore incompressible fluid flow inside a two-sided lid-driven staggered cavity. Results of the lattice Boltzmann simulation for antiparallel motion of lids are compared with the data from existing literature. For parallel motion of lids, the characteristics of flow pattern for a variety of Re numbers (50–3200) are presented. An asymmetric steady-state flow pattern for parallel motion of lids is obtained. 相似文献
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Nina Gusarova Lambert Brandsma Svetlana Malysheva Svetlana Arbuzova Boris Trofimov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Nucleophilic addition of phosphide anions generated from phosphorus red or phosphine to ethenes and ethynes in the presence of super bases to afford organylphosphines and -oxides has been performed. 相似文献
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We study stable blow-up dynamics in the generalized Hartree equation with radial symmetry, which is a Schrödinger-type equation with a nonlocal, convolution-type nonlinearity: First, we consider the -critical case in dimensions and obtain that a generic blow-up has a self-similar structure and exhibits not only the square root blowup rate , but also the log-log correction (via asymptotic analysis and functional fitting), thus, behaving similarly to the stable blow-up regime in the -critical nonlinear Schrödinger equation. In this setting, we also study blow-up profiles and show that generic blow-up solutions converge to the rescaled , a ground state solution of the elliptic equation . We also consider the -supercritical case in dimensions . We derive the profile equation for the self-similar blow-up and establish the existence and local uniqueness of its solutions. As in the NLS -supercritical regime, the profile equation exhibits branches of nonoscillating, polynomially decaying (multi-bump) solutions. A numerical scheme of putting constraints into solving the corresponding ordinary differential equation is applied during the process of finding the multi-bump solutions. Direct numerical simulation of solutions to the generalized Hartree equation by the dynamic rescaling method indicates that the is the profile for the stable blow-up. In this supercritical case, we obtain the blow-up rate without any correction. This blow-up happens at the focusing level , and thus, numerically observable (unlike the -critical case). In summary, we find that the results are similar to the behavior of stable self-similar blowup solutions in the corresponding settings for the nonlinear Schrödinger equation. Consequently, one may expect that the form of the nonlinearity in the Schrödinger-type equations is not essential in the stable formation of singularities. 相似文献
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Prozorova G. F. Korzhova S. A. Pozdnyakov A. S. Emel´yanov A. I. Ermakova T. G. Dubrovina V. I. 《Russian Chemical Bulletin》2015,64(6):1437-1439
Russian Chemical Bulletin - The water-soluble nanocomposite with the uniform distribution of silver nanoparticles in polymer matrix was synthesized on the basis of poly-1-vinyl-1,2,4-triazole.... 相似文献