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排序方式: 共有771条查询结果,搜索用时 31 毫秒
1.
Voronov V. A. Dergachev E. A. Zhukovskii M. E. Neopryatnaya A. M. 《Mathematical Notes》2021,109(1-2):29-37
Mathematical Notes - The problem of finding the least number of variables of a first-order formula expressing the statement that an input-graph contains a subgraph isomorphic to a given... 相似文献
2.
Sorokin N. I. Gaynutdinov R. V. Voronov V. V. Chernova E. V. Fedorov P. P. 《Crystallography Reports》2021,66(1):126-129
Crystallography Reports - The electrical conductivity of natural samples of exogenous silicides has been studied. In the temperature range of 515?700 K, the conductivity increases from 1.1... 相似文献
3.
Avramenko Andriy A. Shevchuk Igor V. Dmitrenko Nataliia P. Skitsko Ivan F. 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12709-12719
Journal of Thermal Analysis and Calorimetry - The paper focuses on the analytical analysis of the propagation of a normal shock wave in an adiabatic gas flow with nanoparticles. A modified... 相似文献
4.
Demishev S. V. Anisimov M. A. Voronov V. V. Gilmanov M. I. Glushkov V. V. Karasev M. S. Filipov V. B. Shitsevalova N. Yu. 《Doklady Physics》2020,65(7):233-237
Doklady Physics - The temperature dependence of the conductivity of the topological Kondo-insulator (TKI) Sm1 – xYbxB6 is investigated in the temperature range 2 < T < 300 K for... 相似文献
5.
Optics and Spectroscopy - The Raman spectra of an Rb2KLuF6 crystal are studied in the temperature range from 8 to 375 K, which includes two phase transitions: one of which proceeds from a cubic to... 相似文献
6.
Dorofeeva T. I. Gubaidulina T. A. Sergeev V. P. Kalashnikov M. P. Voronov A. V. 《Russian Physics Journal》2020,63(7):1186-1194
Russian Physics Journal - Magnetron sputtering, vacuum arc deposition, and ion implantation have been used to create a three-layer anti-corrosive coating structure on stainless steel samples. The... 相似文献
7.
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
8.
9.
Dr. Yuriy Rebets Dr. Elke Brötz Niko Manderscheid Dr. Bogdan Tokovenko Dr. Maksym Myronovskyi Prof. Dr. Peter Metz Dr. Lutz Petzke Dr. Andriy Luzhetskyy 《Angewandte Chemie (International ed. in English)》2015,54(7):2280-2284
Pamamycins are macrodiolides of polyketide origin with antibacterial activities. Their biosynthesis has been proposed to utilize succinate as a building block. However, the mechanism of succinate incorporation into a polyketide was unclear. Here, we report identification of a pamamycin biosynthesis gene cluster by aligning genomes of two pamamycin‐producing strains. This unique cluster contains polyketide synthase (PKS) genes encoding seven discrete ketosynthase (KS) enzymes and one acyl‐carrier protein (ACP)‐encoding gene. A cosmid containing the entire set of genes required for pamamycin biosynthesis was successfully expressed in a heterologous host. Genetic and biochemical studies allowed complete delineation of pamamycin biosynthesis. The pathway proceeds through 3‐oxoadipyl‐CoA, a key intermediate in the primary metabolism of the degradation of aromatic compounds. 3‐Oxoadipyl‐CoA could be used as an extender unit in polyketide assembly to facilitate the incorporation of succinate. 相似文献
10.
Voronov V. P. Belyakov M. Yu. Gorodetskii E. E. Kulikov V. D. Muratov A. R. Nagaev V. B. 《Transport in Porous Media》2003,51(2):123-140
The adiabatic calorimetry method is used to measure the isochoric heat capacity and the dew-bubble curves for the methane-normal pentane mixtures in bulk for three different mixture compositions of n-pentane. The near-critical behavior of the mixture heat capacity indicates that at low n-pentane concentrations, this system is close to the special point of the critical locus. The effect of porous medium has been investigated for one of the mixtures studied in bulk. It has been shown that in porous medium the essential shift of the dew-bubble curve takes place. In our opinion this shift is caused by the formation of wetting film on the surface of porous medium. The estimation of film thickness resulting from the data obtained yields the value 7–8 nm. 相似文献