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排序方式: 共有960条查询结果,搜索用时 15 毫秒
951.
知识产权强国建设的坐标系和参照系应当具有全球性,要求在知识产权强国建设过程中应当高度重视知识产权国际合作,从战略的角度去认识我国所处的国际环境以及在国际知识产权规则变革中的地位和作用,明确我国国际合作战略,探索中国特色知识产权国际合作的新思路和新体制,在国际规则制定中发出更多中国声音、注入更多中国元素,推动国际知识产权规则朝着"普惠包容、平衡有效"的方向发展,维护和拓展我国发展利益。 相似文献
952.
Xueru Shan Weijie Chi Hengbing Jiang Zhangyuan Luo Prof. Cheng Qian Prof. Hongwei Wu Prof. Yanli Zhao 《Angewandte Chemie (International ed. in English)》2023,62(4):e202215652
A design strategy that combines molecular conformation, alkyl chain length, and charge-transfer effects has been developed to obtain conformational and stacking-adaptable donor-acceptor-π type molecules for precisely regulating the monomer and excimer emission in a single luminous platform under different environments. These fluorophores can exhibit bright monomer emissions when they are in the dispersed state based on their planar conformation. However, when the luminous molecules with short alkyl side chains are in the crystalline state, their molecular conformation can become distorted, further inducing strong intermolecular interactions and staggered π-π stacking for bright excimer emission. More importantly, their dispersed and aggregated states can be reversibly regulated in a phase-change fatty acid matrix, to achieve temperature-responsive fluorescence for temperature monitoring and advanced information encryption. 相似文献
953.
Zhi-yuan Mei Genfu Zhao Chenfeng Xia Sheng Cai Qi Jing Xuelin Sheng Han Wang Xiaoxiao Zou Lilian Wang Prof. Hong Guo Prof. Bao Yu Xia 《Angewandte Chemie (International ed. in English)》2023,62(27):e202303871
A novel type of covalent organic frameworks has been developed by assembling definite cobalt-nitrogen-carbon configurations onto carbon nanotubes using linkers that have varying electronic effects. This innovative approach has resulted in an efficient electrocatalyst for oxygen reduction, which is understood by a combination of in situ spectroelectrochemistry and the bond order theorem. The strong interaction between the electron-donating carbon nanotubes and the electron-accepting linker mitigates the trend of charge loss at cobalt sites, while inducing the generation of high spin state. This enhances the adsorption strength and electron transfer between the cobalt center and reactants/intermediates, leading to an improved oxygen reduction capability. This work not only presents an effective strategy for developing efficient non-noble metal electrocatalysts through reticular chemistry, but also provides valuable insights into regulating the electronic configuration and charge behavior of active sites in designing high-performance electrocatalysts. 相似文献
954.
Amey Nimkar Gil Bergman Elad Ballas Nophar Tubul Noam Levi Fyodor Malchik Idan Kukurayeve Munseok S. Chae Daniel Sharon Mikhael Levi Netanel Shpigel Guoxiu Wang Doron Aurbach 《Angewandte Chemie (International ed. in English)》2023,62(50):e202306904
The exploration of cathode and anode materials that enable reversible storage of mono and multivalent cations has driven extensive research on organic compounds. In this regard, polyimide (PI)-based electrodes have emerged as a promising avenue for the development of post-lithium energy storage systems. This review article provides a comprehensive summary of the syntheses, characterizations, and applications of PI compounds as electrode materials capable of hosting a wide range of cations. Furthermore, the review also delves into the advancements in PI based solid state batteries, PI-based separators, current collectors, and their effectiveness as polymeric binders. By highlighting the key findings in these areas, this review aims at contributing to the understanding and advancement of PI-based structures paving the way for the next generation of energy storage systems. 相似文献
955.
Pinar Alayoglu Tieyan Chang Connly Yan Yu-Sheng Chen Neal P. Mankad 《Angewandte Chemie (International ed. in English)》2023,62(51):e202313744
Understanding the electronic structures of high-valent metal complexes aids the advancement of metal-catalyzed cross coupling methodologies. A prototypical complex with formally high valency is [Cu(CF3)4]− ( 1 ), which has a formal Cu(III) oxidation state but whose physical analysis has led some to a Cu(I) assignment in an inverted ligand field model. Recent examinations of 1 by X-ray spectroscopies have led previous authors to contradictory conclusions, motivating the re-examination of its X-ray absorption profile here by a complementary method, resonant diffraction anomalous fine structure (DAFS). From analysis of DAFS measurements for a series of seven mononuclear Cu complexes including 1 , here it is shown that there is a systematic trifluoromethyl effect on X-ray absorption that blue shifts the resonant Cu K-edge energy by 2–3 eV per CF3, completely accounting for observed changes in DAFS profiles between formally Cu(III) complexes like 1 and formally Cu(I) complexes like (Ph3P)3CuCF3 ( 3 ). Thus, in agreement with the inverted ligand field model, the data presented herein imply that 1 is best described as containing a Cu(I) ion with dn count approaching 10. 相似文献
956.
现有的“E”型平衡电枢等效磁路模型仿真研究通常不考虑金属外壳磁阻带来的影响。为了解决平衡电枢换能器中因金属外壳和平衡电枢紧密接触带来的非线性磁阻问题,在现有的平衡电枢换能器等效磁路模型上加入了外壳磁阻影响。分析等效磁路模型磁通部分和力学部分的状态空间方程在不同参数条件下的仿真结果,总结不同参数对该模型阻抗和振膜位移的影响情况。通过仿真对比,外壳磁阻对平衡电枢换能器位移频率响应曲线的影响为1~3 dB。对于组装后包含金属外壳的平衡电枢耳机、助听器产品降低频率响应曲线偏差具有一定的指导意义。 相似文献
957.
污水管网优化计算中动态规划变异形式和比较 总被引:1,自引:0,他引:1
污水管网的优化计算发展至今已经有很多种算法,其中动态规划的产生已经有近40年的时间,在阶段划分上有非序列化动态规划和序列化动态规划的区别,对状态点的数量和定位又有一般动态规划和拟差动态规划的区别,因此针对以埋深作为状态变量的动态规划变异形式做了一些讨论,并分析了它们各自的优缺点。 相似文献
958.
Dr. Laidong Zhou Dr. J. David Bazak Dr. Baltej Singh Chang Li Dr. Abdeljalil Assoud Dr. Nancy M. Washton Dr. Vijayakumar Murugesan Prof. Linda F. Nazar 《Angewandte Chemie (International ed. in English)》2023,62(30):e202300404
We report a new sodium fast-ion conductor, Na3B5S9, that exhibits a high Na ion total conductivity of 0.80 mS cm−1 (sintered pellet; cold-pressed pellet=0.21 mS cm−1). The structure consists of corner-sharing B10S20 supertetrahedral clusters, which create a framework that supports 3D Na ion diffusion channels. The Na ions are well-distributed in the channels and form a disordered sublattice spanning five Na crystallographic sites. The combination of structural elucidation via single crystal X-ray diffraction and powder synchrotron X-ray diffraction at variable temperatures, solid-state nuclear magnetic resonance spectra and ab initio molecular dynamics simulations reveal high Na-ion mobility (predicted conductivity: 0.96 mS cm−1) and the nature of the 3D diffusion pathways. Notably, the Na ion sublattice orders at low temperatures, resulting in isolated Na polyhedra and thus much lower ionic conductivity. This highlights the importance of a disordered Na ion sublattice—and existence of well-connected Na ion migration pathways formed via face-sharing polyhedra—in dictating Na ion diffusion. 相似文献
959.
Prof. Dr. Shi-Chao Qi Yong-Lan Liu Xiao-Jie Lu Yun-Jie Zhao Jia-Xin Li Prof. Dr. Xiao-Qin Liu Prof. Dr. Lin-Bing Sun 《Angewandte Chemie (International ed. in English)》2023,62(27):e202304367
The photo-responsive adsorption has emerged as a vibrant area, but its current methodology is limited by the well-defined photochromic units and their molecular deformation driven by photo-stimuli. Herein, a methodology of nondeforming photo-responsiveness is successfully exploited. With the exploiting agent of Cu-TCPP framework assembled on the graphite and strongly interacted with it, the sorbent generates two kinds of adsorption sites, over which the electron density distribution of the graphite layer can be modulated at the c-axis direction, which can further evolve due to photo-stimulated excited states. The excited states are stable enough to meet the timescale of microscopic adsorption equilibrium. Independent of the ultra-low specific surface area of the sorbent (20 m2 g−1), the CO adsorption capability can be improved from 0.50 mmol g−1 at the ground state to 1.24 mmol g−1 (0 °C, 1 bar) with the visible light radiation, rather than the photothermal desorption. 相似文献
960.
龚卫东 《西昌学院学报(自然科学版)》1999,(3)
依法治国,建设社会主义法制国家是我国现代化建设的一项根本目标。权力制约是法制国家的普遍规律,也是依法治国的内在要求。目的是希望公权的行使在宪法和法律规定的范围和程序之内,国家一切权力属于人民,佘民通过法律形式授予国家权力,从而依靠法律手段来维护公民的意志和利益,监督制约权力。笔者试图从立法、执(司)法及法律监督三方面探索用法律机制对公共权力约束之可行性和科学性,从而保证社会主义法制的有法可依、有法必依、执法必公、违法必究。 相似文献