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CCS Chemistry 2023年第11期5卷 2617-2627页

作者： Mengyi Qiu Xiaorong Zhu Shuowen Bo Kai Cheng Nihan He Kaizhi Gu Dezhong Song Chen Chen Xiaoxiao Wei Dongdong Wang Yingying Liu Shuang Li Xiaojin Tu Yafei Li Qinghua Liu Conggang Li Shuangyin Wang State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082 College of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023 National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230022 Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in Wuhan Collaborative Innovation Center of Chemistry for Life SciencesWuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430064 Institute for Advanced Study Central South UniversityChangsha 410083

Electrocatalytic C–N coupling shows great potential in direct and sustainable urea ***,the mechanism of interaction between catalytic sites and intermediate species is currently unclear,and exploring corresponding strategies to boost urea synthesis is ***,we demonstrated that a multihole structure could preserve the Cu^(+)component of Cu_(2)O spheres under electrochemical reduction *** in situ formed Cu^(0)–Cu^(+)site thermodynamically and kinetically promoted the asymmetric coupling process of^(*)CO and^(*)NO,thereby boosting the urea *** impressive urea yield rates of 29.2 and 114.0 mmol h^(−1)g^(−1)were realized for electrochemical coupling of CO_(2)with nitrate and nitrite,*** multihole-Cu_(2)O exhibits both superior activity and long-term stability compared to the electrocatalysts with a reconstructed Cu^(0)-dominated *** work provides insights into the identification and design of the active site for C–N coupling and urea synthesis.

关键词： asymmetric coupling C-N bond urea synthesis electrocatalysis active site

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热扩散系统中非厄米趋肤效应的观测

Science Bulletin 2024年第9期69卷 1228-1236页

作者：刘云开曹培超祁铭鸿黄强开来高峰彭玉桂李鹰祝雪丰 School of Physics and Innovation Institute Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Extreme Photonics and Instrumentation ZJU-Hangzhou Global Scientiﬁc and Technological Innovation CenterZhejiang UniversityHangzhou 310027China International Joint Innovation Center The Electromagnetics Academy at Zhejiang UniversityZhejiang UniversityHaining 314400China Key Lab.of Advanced Micro/Nano Electronic Devices&Smart Systems of Zhejiang Jinhua Institute of Zhejiang UniversityZhejiang UniversityJinhua 321099China Shaoxing Institute of Zhejiang University Zhejiang UniversityShaoxing 312000China

The paradigm shift of Hermitian systems into the non-Hermitian regime profoundly modifies inherent property of the topological systems, leading to various unprecedented effects such as the nonHermitian skin effect(NHSE). In the past decade, the NHSE has been demonstrated in quantum, optical and acoustic systems. Beside those wave systems, the NHSE in diffusive systems has not yet been observed, despite recent abundant advances in the study of topological thermal diffusion. In this work,we design a thermal diffusion lattice based on a modified Su-Schrieffer-Heeger model and demonstrate the diffusive NHSE. In the proposed model, the asymmetric temperature field coupling inside each unit cell can be judiciously realized by appropriate configurations of structural parameters. We find that the temperature fields trend to concentrate toward the target boundary which is robust against initial excitation conditions. We thus experimentally demonstrated the NHSE in thermal diffusion and verified its robustness against various defects. Our work provides a platform for exploration of non-Hermitian physics in the diffusive systems, which has important applications in efficient heat collection, highly sensitive thermal sensing and others.

关键词： Non-Hermitian skin effect asymmetric coupling Thermal metamaterial Heat diffusion

Enantioselective Pinacol coupling of Aromatic Aldehydes Mediated by TiCl_4(THF)_2/Zn with Tartaric Ester

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Chinese Journal of Chemistry 2004年第9期22卷 950-952页

作者：李有桂江辰赵俊田青杉尤田耙 Department of Chemistry University of Science & Technology of ChinaHefeiAnhui 230026China

asymmetric pinacol coupling of aromatic aldehydes mediated by low valent titanium complexes of chiral ligands derived from natural tartaric acid provided corresponding pinacols in good yields with excellent diastereo-... 详细信息

关键词： pinacol asymmetric coupling enantioselectivity tartaric acid

Enantioselective Pinacol coupling of Aromatic Aldehydes Induced by Chiral Titanium Complexes

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Chinese Chemical Letters 2006年第7期17卷 887-890页

作者： Qing Fang CHENG Xing You XU Ming Yan WANG Jun CHEW Wei Xing MA Xu Jie YANG Department of Chemical Technology Huaihai Institute of Technology Lianyungang 222005 Materials Chemistry Laboratory Nanjing University of Science and Technology Nanjing 210094 不详

asymmetric pinacol coupling of aromatic aldehydes with TiCl4-Zn in the presence of enantiopure squaric acid amidoalcohols afforded 1, 2-diols in excellent yields with high dl- diastereoselectivities and enantioselectivities in the range of 46-89% ee. Some factors influencing dl-diastereoselectivity and enantioselectivity were discussed.

关键词： Chiral squaric acid amidoalcohol pinacol asymmetric coupling aromatic aldehyde.

ADAPTIVE PINNING SYNCHRONIZATION OF COUPLED NEURAL NETWORKS WITH MIXED DELAYS AND VECTOR-FORM STOCHASTIC PERTURBATIONS

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Acta Mathematica Scientia 2012年第3期32卷 955-977页

作者：杨鑫松曹进德 Department of Mathematics Chongqing Normal University Department of Mathematics Southeast University

In this article, we consider the global chaotic synchronization of general cou- pled neural networks, in which subsystems have both discrete and distributed delays. Stochastic perturbations between subsystems are also considered. On the basis of two sim- ple adaptive pinning feedback control schemes, Lyapunov functional method, and stochas- tic analysis approach, several sufficient conditions are developed to guarantee global syn- chronization of the coupled neural networks with two kinds of delay couplings, even if only partial states of the nodes are coupled. The outer-coupling matrices may be symmetric or asymmetric. Unlike existing results that an isolate node is introduced as the pinning target, we pin to help the network realizing synchronization without introducing any iso- late node when the network is not synchronized. As a by product, sufficient conditions under which the network realizes synchronization without control are derived. Numerical simulations confirm the effectiveness of the obtained results.

关键词： Coupled neural networks mixed delays synchronization vector-form noises pinning adaptive asymmetric coupling

Synthesis of a Soluble Diacetylene with Phenylimidazole Ring

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Chemical Research in Chinese Universities 2000年第4期16卷 324-327页

作者： WANG Jiang-hong, CAO Ya-an, CAO Chang-sheng, SHI Yan-hui SHONG Qing, WANG Li-jun and YAO Jian-nian (Institute of Photographic Chemistry, Chinese Academy of Sciences, Beijing 100101, P. R. China Department of Chemistry, Jilin University, Changchun 130023, 中科院感光化学所北京 100101 吉林大学吉林长春 130023

6-(2-Methyl-4-phenyl)-N-imidazole-2, 4-hexadiyn-1-ol was synthesized in a good yield by asymmetric coupling, and the corresponding intermediates were also prepared. The diacetylene monomer could be dissolved in common organic solvents. In addition, all kinds of conditions were also discussed effectively improving the formation of the diacetylene monomer.

关键词： asymmetric coupling Phenylimidazole Ring Polydiacetylene