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排序方式: 共有3859条查询结果,搜索用时 31 毫秒
1.
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
2.
Lithuanian Mathematical Journal - In this paper, we consider estimation of unknown parameters of the tapered Pareto distribution, which belongs to the class of semiheavy distributions, by a sample... 相似文献
3.
4.
Mathematische Zeitschrift - In this paper, we introduce a condition ( $$\mathrm {F}_m'$$ ) on a field K, for a positive integer m, that generalizes Serre’s condition (F) and which still... 相似文献
5.
Denis N. Tomilin Maxim D. Gotsko Lyubov N. Sobenina Igor A. Ushakov Boris A. Trofimov 《Tetrahedron letters》2019,60(28):1864-1867
The cycloadducts of menthofuran with acylbromoacetylenes, (3-bromo-1,6-dimethyl-5,6,7,8-tetrahydro-2H-2,4a-epoxynaphthalen-4-yl)(aryl)methanones, rearrange (CHCl3, reflux, 1 h) to 2-(2-acylethyl)benzofurans (along with the expected 2-bromo-3-hydroxy-4,7-dimethyl-5,6,7,8-tetrahydronaphthalene-1-yl)(aryl)methanones) via 2-acylethynylmenthofurans, thus indicating the exceptionally mild and rapid transfer of four hydrogens from a cyclohexane ring to a triple bond through the furan moiety in the key intermediate 2-acylethynylmenthofuran. 相似文献
6.
Nikonov Igor L. Slepukhin Pavel A. Kopchuk Dmitry S. Kovalev Igor S. Zyryanov Grigory V. Suvorova Anna I. Eltsov Oleg S. Rusinov Vladimir L. Chupakhin Oleg N. 《Chemistry of Heterocyclic Compounds》2019,55(11):1124-1127
Chemistry of Heterocyclic Compounds - An original and convenient procedure has been proposed for one-step preparation of 1-dichloromethyl- and 1-trichloromethylisoquinolines in up to 40% yields via... 相似文献
7.
Kutyashev Igor B. Barkov Alexey Yu. Korotaev Vladislav Yu. Sosnovskikh Vyacheslav Ya. 《Chemistry of Heterocyclic Compounds》2019,55(6):529-540
Chemistry of Heterocyclic Compounds - A regio- and stereoselective method was developed for the synthesis of tetrahydro-4H-spiro[chromeno[3,4-c]pyrrole-1,3'-indolin]-2'-ones in 72−96%... 相似文献
8.
Journal of Thermal Analysis and Calorimetry - We introduce an explicit theoretical formula for the heat capacity peaks that occur in materials during phase changes. Such materials are of importance... 相似文献
9.
Jorge Ferreira Raquel Zilz Igor S. Boeira Sabrina M. da Silva Adriana C.A. Casagrande Osvaldo L. Casagrande 《应用有机金属化学》2019,33(3)
A new set of Cr(III) complexes, {L}CrCl3(THF), based on thiophene–imine ( 2a , L = PhOC6H4(N═CH)‐2‐SC4H3; 2b , L = PhOC2H4(N═CH)‐2‐SC4H3; 2c , L = Ph(NH)C2H4(N═CH)‐2‐SC4H3; 2d , L = PhOC6H4(N═CH)‐2‐SC4H2‐5‐Ph; 2e , L = Ph(NH)C2H4(N═CH)‐2‐SC4H2‐5‐Ph) have been prepared and characterized using elemental analysis and infrared spectroscopy. Upon activation with methylaluminoxane, all the chromium complexes generated active systems affording a nonselective distribution of α‐olefins with turnover frequencies in the range 9500–93 500 (mol ethylene) (mol Cr)?1 h?1, and producing mostly oligomers (95.0–99.3 wt% of total products). Small amounts of polymer were produced in these oligomerization reactions (0.8–8.2 wt%). The catalytic activities were quite sensitive to the ligand environment. Moreover, the effects of oligomerization parameters (temperature, [Al]/[Cr] molar ratio, time) on the activity and on the product distribution were examined. 相似文献
10.
Igor N. Karnaukhov 《Physics letters. A》2019,383(33):125951
A generalization of the Mattis-Nam model Mattis and Nam (1972) [7], which takes into account a correlated hopping and pairing of electrons, is proposed, its exact solution is obtained. In the framework of the model the stability of the zero energy Majorana fermions localized at the boundaries is studied in the chain in which electrons interact through both the on-site Hubbard interaction and the correlated hopping and pairing. The ground-state phase diagram of the model is calculated, the region of existence of topological states is determined. It is shown that low-energy excitations destroy bonds between electrons in the chain, leading to an insulator state. 相似文献