排序方式: 共有58条查询结果,搜索用时 156 毫秒
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Ashot S. Saghyan Ani S. Dadayan Slavik A. Dadayan Anna F. Mkrtchyan Arpine V. Geolchanyan Luiza L. Manasyan Hrant R. Ajvazyan Victor N. Khrustalev Hasmik H. Hambardzumyan Victor I. Maleev 《Tetrahedron: Asymmetry》2010,21(24):2956-2965
New fluorine-containing chiral auxiliaries (S)-N-(2-benzoylphenyl)-1-(2-fluorobenzyl)-, (S)-N-(2-benzoylphenyl)-1-(3-fluorobenzyl)-, and (S)-N-(2-benzoylphenyl)-1-(4-fluorobenzyl)-pyrrolidine-2-carboxamide and their NiII complexes of Schiff bases with glycine and alanine have been synthesized. The greater efficiency of the complexes in terms of faster reaction rates and stereoselectivities in the asymmetric synthesis of (S)-α-amino acids has also been demonstrated. 相似文献
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Ovakimyan M. Zh. Gasparyan G. Ts. Poghosyan A. S. Bichakhchyan A. S. Derdzyan L. V. Stepanyan H. M. Muradyan R. E. 《Russian Journal of General Chemistry》2021,91(8):1494-1498
Russian Journal of General Chemistry - The reactions of (1-bromoethenyl)(diphenyl)phosphine oxide with NH-, OH-, SH-nucleophiles were studied. The reaction of phosphine oxide with alcohols and... 相似文献
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Dispersion equations for TE and TM modes in width-limited waveguides formed by parallel cylindrical surfaces are derived in adiabatic approximation. It is shown that the dominant TE01 mode is strongly localized in the waveguide center. 相似文献
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Poghosyan AH Arsenyan LH Gharabekyan HH Falkenhagen S Koetz J Shahinyan AA 《Journal of colloid and interface science》2011,363(1):175-181
Well-aligned ZnO nanorods (NRs) were grown on indium-tin-oxide (ITO) slide by the hydrothermal method and used as templates for preparing ZnO/Au composite nanoarrays. The optical and morphological properties of ZnO/Au composites under various HAuCl(4) concentrations were explored via UV-vis absorption spectroscopy, photoluminescence (PL) and scanning electron microscopy (SEM). The density and size of gold nanoparticles (Au NPs) on ZnO NRs can be controlled by adjusting the concentration of HAuCl(4). The optimal ZnO/Au composites display complete photocatalytic degradation of methyl blue (MB) within 60 min, which is superior to that with pure ZnO NRs prepared by the same method. The reason of better photocatalytic performance is that Au NPs act as electron traps and it prevents the rapid recombination of electrons and holes, resulting in the improvement of photocatalytic efficiency. The photocatalytic performance of ZnO/Au composites is mainly controlled by the density of Au NPs formed on ZnO NRs. The application in rapid photodegradation of MB shows the potential of ZnO/Au composite as a convenient catalyst for the environmental purification of organic pollutants. 相似文献
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The process of micelle formation in an aqueous solution of the surfactant was simulated by the computer experiment. It was established by the molecular dynamics method that micelles are formed through the formation of premicellar associates of the surfactant. The practical absence of an attraction between single molecules of sodium pentadecyl sulfonate (SPDS) and premicellar associates dissolved in water was shown for a SPDS—water system. The function of the radial distribution of Na+ counterions towards polar groups of SPDS molecules in water and on the surfaces of micelles and premicellar associates was studied by the molecular dynamics method. The presence of dissociated and non-dissociated polar groups of the SPDS molecular on the micelle surface was found. The data obtained are consistent with the existence concepts on micelle formation processes. 相似文献
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Emma H. Chukhajian Martiros K. Nalbandyan Hasmik R. Gevorkyan Eliza H. Chukhajian Henrik A. Panosyan Armen G. Ayvazyan Rafael A. Tamazyan 《Journal of heterocyclic chemistry》2008,45(3):687-692