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81.
82.
Almir S. Gazizov Andrey V. Smolobochkin Ekaterina A. Anikina Julia K. Voronina Alexander R. Burilov Michail A. Pudovik 《合成通讯》2017,47(1):44-52
Herein we report our studies on the acid-catalyzed cyclisation of N-(4,4-diethoxybutyl)sulfonamides at the presence of polyatomic phenols as an efficient one-pot approach to the synthesis of 1-sulfonyl-2-arylpyrrolidines from the acyclic precursors. 相似文献
83.
Levina EV Kalinovsky AI Dmitrenok PS Martyyas EA Stonik VA 《Natural product communications》2010,5(11):1737-1742
New steroid glycosides, hylodoside A (1) and novaeguinoside Y (2), along with previously known polyhydroxylated steroids (3-7) were isolated from the ethanolic extracts of the starfish Leptasterias hylodes reticulata and Culcita novaeguineae (juvenile). The structures have been elucidated using 1D and 2D NMR spectra (1H, 13C, DEPT, COSY-45, 1D-TOCSY, HSQCGP, ROESY, HSQC and HMBCGP) and mass spectrometry. Compound 3 was shown to inhibit the growth of Staphylococcus aureus up to 10% from the control at a concentration of 1 mg/mL. Steroids 1, 2 and 5 showed moderate hemolytic activity in the mouse erythrocytes assay. Compounds 3, 4 and 6 displayed pH-depended hemolytic properties. 相似文献
84.
Vladimir Anashin Andrei Khrennikov Ekaterina Yurova 《Designs, Codes and Cryptography》2014,71(3):383-407
The paper presents new criteria for bijectivity/transitivity of T-functions and a fast knapsack-like algorithm of evaluation of a T-function. Our approach is based on non-Archimedean ergodic theory: Both the criteria and algorithm use van der Put series to represent 1-Lipschitz p-adic functions and to study measure-preservation/ergodicity of these. 相似文献
85.
Ekaterina Vladimirovna Bulinskaya 《Journal of Theoretical Probability》2014,27(3):878-898
Critical catalytic branching random walk on an integer lattice ? d is investigated for all d∈?. The branching may occur at the origin only and the start point is arbitrary. The asymptotic behavior, as time grows to infinity, is determined for the mean local particles numbers. The same problem is solved for the probability of the presence of particles at a fixed lattice point. Moreover, the Yaglom type limit theorem is established for the local number of particles. Our analysis involves construction of an auxiliary Bellman–Harris branching process with six types of particles. The proofs employ the asymptotic properties of the (improper) c.d.f. of hitting times with taboo. The latter notion was recently introduced by the author for a non-branching random walk on ? d . 相似文献
86.
87.
Režnar Tomáš Martinovič Jan Slaninová Kateřina Grakova Ekaterina Vondrák Vít 《Central European Journal of Operations Research》2017,25(3):545-560
Central European Journal of Operations Research - The probabilistic time-dependent vehicle routing problem is presented in this paper. It is a novel variant of the vehicle routing problem. The... 相似文献
88.
Vlad V. Travkin Georgy L. Pakhomov Ekaterina E. Terukova 《Molecular Crystals and Liquid Crystals》2014,589(1):154-161
We analyze the current-vs-voltage (J-V) characteristics of ITO/C60/Al sandwich cells, where ITO is the double indium tin oxide, C60 is the buckminsterfullerene and Al is the thermally evaporated top aluminum electrode. These cells were obtained on either glass/ITO or polyethyleneterephthalate/ITO substrates (or, optionally, on glass/ZnO substrates) in a parallel process under identical conditions. However, the J-V dependences in each series behave very differently. The results are discussed in terms of the migration of admixtures from a bulk substrate material toward the top metallic electrode, thus modifying the photovoltaic properties of cells. 相似文献
89.
We find that the CP-violating asymmetry
at the one-loop order within the minimal supersymmetric extension of the standard model is of the order of few percent for maximal CP violation. It could be measured by considering the rate difference in the one-lepton events. 相似文献
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90.
New chiral amidophosphites were synthesized and tested in the Ir-catalyzed hydrogenation of 4-substituted 1,3-dihydro-2H-1,5-benzodiazepin-2-ones and Rh-catalyzed hydrogenation of dehydro amino acid derivatives. The triphenylphosphine additive can considerably increase the enantioselectivity of both processes. 相似文献