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241.
Huadong Yuan Prof. Jianwei Nai Dr. Yongjin Fang Gongxun Lu Prof. Xinyong Tao Prof. Xiong Wen Lou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):15973-15977
The growth of Li dendrites hinders the practical application of lithium metal anodes (LMAs). In this work, a hollow nanostructure, based on hierarchical MoS2 coated hollow carbon particles preloaded with sulfur (C@MoS2/S), was designed to modify the LMA. The C@MoS2 hollow nanostructures serve as a good scaffold for repeated Li plating/stripping. More importantly, the encapsulated sulfur could gradually release lithium polysulfides during the Li plating/stripping, acting as an effective additive to promote the formation of a mosaic solid electrolyte interphase layer embedded with crystalline hybrid lithium-based components. These two factors together effectively suppress the growth of Li dendrites. The as-modified LMA shows a high Coulombic efficiency of 98 % over 500 cycles at the current density of 1 mA cm−2. When matched with a LiFePO4 cathode, the assembled full cell displays a highly improved cycle life of 300 cycles, implying the feasibility of the proposed LMA. 相似文献
242.
Dr. Gang Liao Dr. Tao Zhang Zhi-Keng Lin Prof. Dr. Bing-Feng Shi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):19941-19954
Transition metal-catalyzed enantioselective functionalization of C−H bond, the most abundant functionality in organic molecules, has emerged as an expedient synthetic approach to streamline the synthesis of complex chiral molecules. Despite significant progress, traditional directing group-enabled strategies require additional steps for the installation and removal of directing groups from the target molecule. The recently developed asymmetric C−H functionalization using chiral transient directing groups (cTDGs) offers a promising alternative that can circumvent this obstacle and therefore simplify the process. In this Minireview, we briefly discuss the advent and recent advances of this emerging concept, with an emphasis on discussing the creation of various stereogenic centers and the developments of cTDGs. Applications in natural product synthesis and ligand derivatizations are also discussed. We hope this Minireview will highlight the great potential of this strategy and help to inspire further endeavors. 相似文献
243.
244.
Honghua Zhang Huihong Wang Yi Jiang Fei Cao Weiwei Gao Longqing Zhu Yuhang Yang Xiaodong Wang Yongqiang Wang Jinhong Chen Yiyue Feng Xuemei Deng Yingmei Lu Xiaoling Hu Xiangxiang Li Juan Zhang Tao Shi Prof. Zhen Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(72):17289-17317
Sulfur-containing scaffold, as a ubiquitous structural motif, has been frequently used in natural products, bioactive chemicals and pharmaceuticals, particularly C−S/N−S bonds are indispensable in many biological important compounds and pharmaceuticals. Development of mild and general methods for C−S/N−S bonds formation has great significance in modern research. Iodine and its derivatives have been recognized as inexpensive, environmentally benign and easy-handled catalysts or reagents to promote the construction of C−S/N−S bonds under mild reaction conditions, with good regioselectivities and broad substrate scope. Especially based on this, several new strategies, such as oxidation relay strategy, have been greatly developed and accelerated the advancement of this field. This review focuses on recent advances in iodine and its derivatives promoted hybridized C−S/N−S bonds formation. The features and mechanisms of corresponding reactions are summarized and the results of some cases are compared with those of previous reports. In addition, the future of this domain is discussed. 相似文献
245.
246.
Yaochen Zheng Jian Liu Yan Guo Qian Zhang Xuan Gao Zhengguo Gao Tao He Qingfu Ban 《Journal of polymer science. Part A, Polymer chemistry》2020,58(12):1664-1674
Cationic compounds often serve as antibacterial materials for a wide range of applications. However, the relationship of topology−antibacterial activity has been rarely revealed. Herein, three cationic polythioethers (CPTEs) with hyperbranched topologies are well designed and facilely synthesized via an all-click chemistry strategy (including thiol-ene and epoxy-amine additions). These as-prepared CPTEs were found to exhibited outstanding antibacterial activity against Escherichia coli and Staphylococcus aureus with minimum inhibitory concentrations against E. coli of 7.3, 14.6, and 14.6 μg ml−1, and against S. aureus of 14.6, 29.2, and 29.2 μg ml−1, respectively. The antibacterial activity is coincident with their degree of branching (DB, their DB values of 0.81, 0.48, and 0.27), which is mainly attributed to the inherent three-dimensional structure. The present strategy reveals the relationship of polymer topology and antibacterial activity, providing a novel possibility for designing and/or synthesis of high-efficiency antibacterial agents. 相似文献
247.
Chen Xiao-Lu Li Xiang-Yu Li Shuai-Shuai Bai Xue Li Tao Goud Erukala Yadaiah Zhong Chong-Min Zuo Ya-Jie 《Russian Journal of General Chemistry》2020,90(11):2163-2169
Russian Journal of General Chemistry - The Grubbs–Hoveyda catalysts have a wide range of applications in catalyzed formation of the carbon-carbon double bonds. In this study, several... 相似文献
248.
Zhang Hanshuai Sheng Xiaohui Wang Siwen Xu Tao 《Journal of Thermal Analysis and Calorimetry》2020,141(3):1183-1195
Journal of Thermal Analysis and Calorimetry - Nowadays, the stability and heat transfer properties of nanofluids have been extensively studied. However, for the practical application, the dynamic... 相似文献
249.
Nonlinear Dynamics - This work presents a general class of prototype birhythmic dynamical systems, which can be extensively used to study the generation of complex bifurcation of limit cycles.... 相似文献
250.
Ding Yunqiao Li Junying Wang Shijie Junzhang Mu Qiuhong Wang Jingui 《Structural chemistry》2018,29(5):1499-1510
Structural Chemistry - The reaction mechanisms of several amino acids (Asn, Gln, Arg, His, and Lys) in the collagen with aldehyde were studied using density functional theory method. Based on the... 相似文献