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排序方式: 共有2698条查询结果,搜索用时 203 毫秒
1.
Yin Qingqing Xu Fen Sun Lixian Li Yaying Liao Lumin Wang Tao Guan Yanxun Xia Yongpeng Zhang Chenchen Wei Sheng Zhang Huanzhi Li Bin 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6583-6592
Journal of Thermal Analysis and Calorimetry - Polyethylene glycol (PEG) is widely used as phase change materials (PCMs). However, the leakage and low thermal conductivity issues restrict its... 相似文献
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Designs, Codes and Cryptography - The discrete logarithm problem arises from various areas, including counting the number of points of certain curves and diverse cryptographic schemes. The... 相似文献
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Designs, Codes and Cryptography - The Learning-With-Errors (LWE) problem (and its variants including Ring-LWE and Module-LWE), whose security are based on hard ideal lattice problems, has proven to... 相似文献
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Dr. Zhoulong Fan Katherine L. Bay Dr. Xiangyang Chen Zhe Zhuang Han Seul Park Dr. Kap-Sun Yeung Prof. Dr. K. N. Houk Prof. Dr. Jin-Quan Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(12):4800-4807
A simple and efficient nitrile-directed meta-C−H olefination, acetoxylation, and iodination of biaryl compounds is reported. Compared to the previous approach of installing a complex U-shaped template to achieve a molecular U-turn and assemble the large-sized cyclophane transition state for the remote C−H activation, a synthetically useful phenyl nitrile functional group could also direct remote meta-C−H activation. This reaction provides a useful method for the modification of biaryl compounds because the nitrile group can be readily converted to amines, acids, amides, or other heterocycles. Notably, the remote meta-selectivity of biphenylnitriles could not be expected from previous results with a macrocyclophane nitrile template. DFT computational studies show that a ligand-containing Pd–Ag heterodimeric transition state (TS) favors the desired remote meta-selectivity. Control experiments demonstrate the directing effect of the nitrile group and exclude the possibility of non-directed meta-C−H activation. Substituted 2-pyridone ligands were found to be key in assisting the cleavage of the meta-C−H bond in the concerted metalation–deprotonation (CMD) process. 相似文献
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Meccanica - In this work, a bond-based peridynamic de-icing model has been developed to simulate the thermo-mechanical ice removal process of frozen structures. In the proposed numerical method,... 相似文献
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One‐Pot Synthesis of Pomegranate‐Structured Fe3O4/Carbon Nanospheres‐Doped Graphene Aerogel for High‐Rate Lithium Ion Batteries 下载免费PDF全文
Dr. Dafang He Lixian Li Fengjuan Bai Chenyang Zha Prof. Liming Shen Prof. Harold H. Kung Prof. Ningzhong Bao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(13):4454-4459
A unique hierarchically nanostructured composite of iron oxide/carbon (Fe3O4/C) nanospheres‐doped three‐dimensional (3D) graphene aerogel has been fabricated by a one‐pot hydrothermal strategy. In this novel nanostructured composite aerogel, uniform Fe3O4 nanocrystals (5–10 nm) are individually embedded in carbon nanospheres (ca. 50 nm) forming a pomegranate‐like structure. The carbon matrix suppresses the aggregation of Fe3O4 nanocrystals, avoids direct exposure of the encapsulated Fe3O4 to the electrolyte, and buffers the volume expansion. Meanwhile, the interconnected 3D graphene aerogel further serves to reinforce the structure of the Fe3O4/C nanospheres and enhances the electrical conductivity of the overall electrode. Therefore, the carbon matrix and the interconnected graphene network entrap the Fe3O4 nanocrystals such that their electrochemical function is retained even after fracture. This novel hierarchical aerogel structure delivers a long‐term stability of 634 mA h g?1 over 1000 cycles at a high current density of 6 A g?1 (7 C), and an excellent rate capability of 413 mA h g?1 at 10 A g?1 (11 C), thus exhibiting great potential as an anode composite structure for durable high‐rate lithium‐ion batteries. 相似文献
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