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1.
A Structural Property Concerning Abstract Commensurability of Subgroups   总被引:1,自引:0,他引:1  
Further properties of a group introduced by the first authorin 1980 (sometimes called the first Grigorchuk group) are established.These are notably that any two infinite finitely generated subgroupsof have isomorphic subgroups of finite index and that the generalizedword problem for is soluble.  相似文献   
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Molecular Diversity - A series of 5-oxo-4H-pyrrolo[3,2-b]pyridine derivatives was identified as novel class of highly potent antibacterial agents during an extensive large-scale high-throughput...  相似文献   
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The nanotechnology development is accompanied by an intensive growth of information flow which is specially noticeable as applied to journal information flow. Now over the world there are the 69 nano-titled journals with the impact factor and/or a settled periodicity as well as the 70 those which lack stability periodicity and are in an organization stage. Only 49 nano-titled have the impact factor with the comparatively high mean value of about 3.44. The domestic nano-titled journals published in Russia, India, China, and other countries are also considered. The attention is taken that in the 2006–2010 period the 95 new nano-titled journals were organized and in 2011 this process is continuing and seems to be the most impressive. Many nano-related journals (including classical physical, chemical and materials science ones) are also described and discussed.  相似文献   
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In present research, we investigate dynamic coupled thermoelasticity problem for a “coating-substrate” system. We present a number of models of thermoelastic deformation of the “coating-substrate” system with thermomechanical characteristics which may vary both continuously and discontinuously. To solve these problems, we use the variational principle of coupled thermoelasticity in the Laplace transforms space and hypotheses on a distribution of temperature and displacements transforms. The transforms inversion is realized according to the Durbin method. The calculations were carried out based on both proposed simplified models and FEM.  相似文献   
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Chemistry of Natural Compounds - The aerial part of Lespedeza tomentosa (Thunb.) Maxim. growing in southern Primorsky Krai, Russian Federation, yielded 10 identified flavonoid glycosides, eight of...  相似文献   
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Reaction of 5-arylethynyl-2-methyl-2H-tetrazoles (acetylene tetrazoles) with arenes under the action of Brønsted superacid CF3SO3H or acidic zeolite HUSY CBV-720 gives rise to E-/Z-5-(2,2-diarylethenyl)-2-methyl-2H-tetrazoles, as products of hydroarylation of acetylene bond, in yields up to 98% with predominant formation of E-isomers. Cationic intermediates of these reactions have been studied theoretically by DFT calculations. Addition of CF3SO3H to the triple bond of acetylene tetrazoles leads to the corresponding E-/Z-vinyl triflates in high yields. Hydration of triple bond in these tetrazoles in H2SO4 results in the formation of 5-(2-aryl-2-oxoethyl)-2-methyl-2H-tetrazoles. Tandem hydroarylation-ionic hydrogenation of acetylene tetrazoles in the systems acid(CF3SO3H or AlCl3)-arene-cyclohexane affords 5-(2,2-diarylethyl)-2-methyl-2H-tetrazoles.  相似文献   
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