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981.
Acta Mathematicae Applicatae Sinica, English Series - This paper evaluates the performance of the FW-test for testing part of p-regression coefficients in linear panel data model when p is... 相似文献
982.
Experimental Mechanics - There have been relatively few studies on mechanical properties of nanomaterials under high strain rates, mainly due to the lack of capable nanomechanical testing devices.... 相似文献
983.
Zhang Menghua Zhang Yongfeng Ouyang Huimin Ma Changhui Cheng Xingong 《Nonlinear dynamics》2020,99(4):2727-2741
Nonlinear Dynamics - An adaptive integral sliding mode control (AISMC) method with payload sway reduction is presented for 4-DOF tower cranes in this paper. The designed controller consists of... 相似文献
984.
Dr. Ruofei Cheng Prof. Dr. Zaozao Qiu Prof. Dr. Zuowei Xie 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(32):7212-7218
Iridium-catalyzed formal alkyne hydroboration with cage B−H of o-carborane has been achieved, leading to the controlled synthesis of a series of 3,6-[trans-(AlkCH=CH)]2-o-carboranes (Alk=alkyl), 3-cis-(ArCH=CH)-o-carboranes (Ar=aryl), and 3-cis-(ArCH=CH)-6-trans-(AlkCH=CH)-o-carboranes in high yields with excellent regio- and very good cis–trans selectivity. The most electron-deficient B(3,6)−H vertices favor oxidative addition on electron-rich metal centers, which is responsible for the regioselectivity. On the other hand, the configuration of the resultant olefinic units is dominated by alkyne substituents. Alkyl groups lead to a trans-configuration whereas bulky aryl substitutions result in cis-configuration. 相似文献
985.
Yangang Cheng Yan Liu Jinyan Tan Yanping Sun Wei Guan Yuan Liu Bingyou Yang Haixue Kuang 《Biomedical chromatography : BMC》2020,34(9):e4881
Our previous work demonstrated that total withanolides of Datura metel L. leaves (TWD) exhibited excellent therapeutic effects on psoriasis. However, current knowledge of its mechanisms is incomplete. In this study, integrated spleen and thymus untargeted metabolomics were used to analyze the changes in endogenous metabolites underlying the immunosuppressive activity of TWD on psoriasis animal models induced by imiquimod. The results suggested that TWD treatment markedly attenuated imiquimod-induced psoriasis and showed significant immunosuppressive activity as evidenced by decreased elevation index of spleen and thymus. Meanwhile, TWD significantly reversed the elevation of immunoregulatory factors, including IL-10, IL-17, IL-22 and IL-23. Multivariate trajectory analysis revealed that TWD treatment could restore the psoriasis-disturbed spleen and thymus metabolite profiles towards the normal metabolic status. A total of 25 and 27 metabolites associated with the immunomodulatory effects for which levels changed markedly upon treatment have been identified in spleen and thymus, respectively. These differential metabolites were mainly involved in amino acid metabolism, nucleotide metabolism, fatty acid metabolism and lipid metabolism. Our investigation provided a holistic view of TWD for intervention in psoriasis through immunoregulation and provided further scientific information in vivo about a clinical value of TWD for psoriasis. 相似文献
987.
988.
Jie‐Lian Han Ying Qin Cheng‐Wei Ju Dongbing Zhao 《Angewandte Chemie (International ed. in English)》2020,59(16):6555-6560
Organosilicon compounds have been extensively utilized both in industry and academia. Studies on the syntheses of diverse organosilanes is highly appealing. Through‐space metal/hydrogen shifts allow functionalization of C?H bonds at a remote site, which are otherwise difficult to achieve. However, until now, an aryl to alkyl 1,5‐palladium migration process seems to have not been presented. Reported herein is the remote olefination, arylation, and borylation of a methyl group on silicon to access diverse vinyl‐, benzyl‐, and borylsilanes, constituting a unique C(sp3)?H transformation based on a 1,5‐palladium migration process. 相似文献
989.
Wang C. Cheng S. Y. Zhao W. W. Yang X. N. Zhou K. Z. Tian J. J. Jiang D. F. Ma P. H. 《Crystallography Reports》2020,65(7):1156-1160
Crystallography Reports - This paper reports on the supramolecular self-assembly of cyclopentano cucurbit[5]uril (CyP5Q[5]), L-phenylalanine (L-Phe), and cadmium ions. The crystal structure is... 相似文献
990.
The processes of electric ion extraction from plasma induced by pulse lasers are simulated by particle-in-cell(PIC)method and hybrid-PIC method.A new calculation scheme named preprocessing hybrid-PIC is presented because neither of the two methods above is omnipotent,especially under the circumstance of high initial plasma density.The new scheme provides credible results with less computational consumption than PIC method in both one-and two-dimensional simulations,except forΠ-type electrode configuration.The simulation results show that the M-type performs best in all electrode configurations in both high-density and low-density plasma conditions. 相似文献