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991.
Jie Feng Hongyang Zhao Wajid Ali Dandan Yin Xinyang Li Nawab Ali Khan Prof. Shujiang Ding 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(71):17818-17823
Coordination polymers are promising cathode materials for rechargeable alkaline batteries. Therefore, the precise modulation of these cathodes by chemical structure and in-depth structure transform study is necessary. Here, two model coordination polymer battery cathodes were designed to demonstrate the dynamic structure–performance relationship. We studied the electrochemical performance of two kinds of nickel-based coordination polymer, comprising a planar 2D cyanide-bridged network and a 3D cyanide-bridged network pillared by pyrazine molecules. The 2D coordination polymer showed serious voltage degradation with poor rate capability, whereas the 3D coordination polymer exhibited stable voltage output coupled with high rate at various current densities. The investigation revealed the underlining relationship of plateau voltage degradation and hydrolysis process of electrodes. It was revealed that the pyrazine pillar molecules in the 3D coordination polymer could suppress the hydrolysis and lead to the in situ formation of partially hydrolyzed structure with excellent electrochemical kinetics; this exhibited obvious smaller peak separation (27 mV compared with 149 mV) and hence an almost twofold increase in capacity retention (31.9 to 50.0 %) and energy density retention (18.2 to 35.9 %) at 10 A g−1. 相似文献
992.
Siyuan Li Feng Jin Mayavan Viji Hyeju Jo Jaeuk Sim Hak Sung Kim Heesoon Lee Jae-Kyung Jung 《Tetrahedron letters》2017,58(14):1417-1420
An efficient and facile two-step strategy for the synthesis of (Z)-aurone from arylacetylenes and salicyladehydes, via silver(I) nitrate mediated cyclization/oxidation in the presence of potassium carbonate has been developed. The key feature of our method was delicate cascade reaction, to provide the corresponding (Z)-aurone in high yield and good regio- and stereo selectivity. 相似文献
993.
994.
Da Yan He Zhan Jiang Li Zhong Jun Li Yun Qi Liu Dong Xu Qiu Meng Shen Cai 《合成通讯》2013,43(18):2653-2658
Cabohydrates reacting with acetone in the presence of molecular sieve and p—toluene sulfonic acid provided a simple, convenient, high yield and good selective process for preparation of isopropylidene carbohydrates. 相似文献
995.
Xiang Dong Rui Sang Qiang Wang Dr. Xiang‐Ying Tang Prof. Min Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(50):16910-16915
996.
Guomin Ai Jinxing Zhu Xiuzhu Dong Tong Sun 《Rapid communications in mass spectrometry : RCM》2013,27(17):1935-1944
997.
Lei Wang Ruiquan Liu Cong Lv Junjun Ou Feng Liu Shangzhong Liu Min Wang Jiangchun Zhong 《Tetrahedron: Asymmetry》2013,24(4):173-177
Six optically active α-hydroxyl-β,γ-unsaturated acid esters 1a to 1f were synthesised, and they are significant moieties of the cerebrosides. The chiral intermediate alkynol 4 prepared by catalytic asymmetric addition had 99% ee, and which was converted into the target compounds 1a to 1f with high enantiomeric purity. 相似文献
998.
Qian Wang Assoc. Prof. Fuhang Song Dr. Xue Xiao Pei Huang Assoc. Prof. Li Li Prof. Aaron Monte Dr. Wael M. Abdel‐Mageed Dr. Jian Wang Hui Guo Dr. Wenni He Feng Xie Dr. Huanqin Dai Miaomiao Liu Dr. Caixia Chen Hao Xu Assoc. Prof. Mei Liu Dr. Andrew M. Piggott Assoc. Prof. Xueting Liu Prof. Robert J. Capon Prof. Lixin Zhang 《Angewandte Chemie (International ed. in English)》2013,52(4):1231-1234
999.
A Fuzzy Principal Component Analysis Approach to Hierarchical Evaluation Model for Balanced Supply Chain Scorecard Grading 总被引:1,自引:0,他引:1
Sidong Xian Dong Qiu Shiyun Zhang 《Journal of Optimization Theory and Applications》2013,159(2):518-535
Effective performance management is critical to efficient supply chain management systems with the balanced scorecard as well as to effective evaluation models and their algorithms. Problems often encountered in the modeling of the balanced scorecard for supply chain are how to overcome the multicollinearity in its index system. In this paper, a new fuzzy hierarchical evaluation model featuring the criteria of the balanced supply chain scorecard is proposed and analyzed on the basis of data about Chinese firms. The model, based on the fuzzy weight’s matrix derived from a fuzzy principal component analysis, overcomes the multicollinearity in the index system of the balanced supply chain scorecard. This method proves good performance in determining the weight distribution matrix of the fuzzy hierarchical evaluation and improves the evaluation accuracy and generalization as shown for a group of firms in western China. 相似文献
1000.
Multilayered gels play an important role in biomedical engineering as drug delivery vehicles, replacement tissues and bio-mimetic substrates for cell cultures. It has been established that the gel elasticity strongly influences the intended functionalities. In view of this, second-order elastic solutions for the stresses and displacements in cylindrical multilayered hydrogels subjected to various dilatation profiles are developed in this paper. The results emphasize the importance of nonlinearity in gel mechanics, and suggest the possibility of a rational selection of layer elasticities, layer thicknesses and dilatation profiles for improved mechanical responses such as maximum/minimum swelling and multiaxial stress states. 相似文献