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Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

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Science china chemistry 2006年第4期49卷 296-307页

作者： LI Ming1, ZHENG Wenxu2 & TIAN Anmin2 1. department of chemistry, Southwest-china Normal {3., Chongqing 400715, china 2. department of chemistry, Sichuan {3., Chengdu 610064, china 1. department of chemistry Southwest-China Normal University Chongqing 400715 China 2. department of chemistry Sichuan University Chengdu 610064 China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3.YP/6-3.g(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

Studies on the Interaction of 12-Tungstophosphoric Acid and Diethylene Glycol

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Chemical Research in Chinese Universities 1993年第4期9卷 317-323页

作者： ZHAO Yu-sheng, HUA Shi-ying , WU Tong-hao and WEI Quan (department of chemistry, jilin {3., Changchun, 13.023. Worked in Institute of Theoretical chemistry, jilin {3., Changchun.

The homogeneous system of 12-tungstophosphoric acid and diethylene glycol was studied using IR and NMR spectra. It was found that the protons in 12-tungstophosphoric acid formed proton oxonium ions with the hydroxyl oxygen in diethylene glycol by hydrogen-bonds, and the formed proton oxonium ions could react with the terminal oxygens of heteropoly anions. The dehydration-cyclization mechanism of diethylene glycol in the presence of heteropoly acid was also proposed.

关键词： IR NMR Diethylene glycol Proton oxonium ions

Rank of loop, constraint degree of path, coupling degree of graph and their application

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Progress in Natural Science:Materials International 2005年第2期15卷 79-85页

作者： YANG Tingli1*, LUO Yufeng2, ZHANG Ce3.and YAO Fanghua1(1. SINOPIC Jinling Petrochemical Corp., Nanjing 21003., china 2. department of Mechanical Engineering, Nanchang university, Nanchang 3.0029, china 3. department of Mechanical Engineering, Tianjin university, Tianjin 3.0072, china) SINOPIC Jinling Petrochemical Corp. Nanjing 210037 China. department of Mechanical Engineering Nanchang University Nanchang 330029 China. department of Mechanical Engineering Tiánjin University Tianjin 300072 China

Some new concepts (rank of a loop, degree of freedom of a graph, path unit and ordered path arrangement, constraint degree of path, coupling degree of a graph, basic graph, etc.), formulas, and algorithms, are proposed in this paper. Based on these concepts, a new systematic theory and practical method for the design of topological structure, kinematics and dynamics of mechanical systems is established. Some conjectures and problems needed to be researched are also put forward. The concepts, formulae and algorithms presented in this paper will find wide potential applications.

关键词： rank of loop degree of freedom of graph constraint degree of path coupling degree of graph

X-ray spectra induced in highly charged 40Ar^q+ interacting with Au surface

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 203-212页

作者： ZHANG Xiao’an1,2, XIAO Guoqing1, YANG Zhihu1, CHEN Ximeng3. ZHAO Yongtao1, LI Fuli4, ZHANG Yinping1, CUI Ying3. ZHANG Hongqiang3. XU Xu3. SHAO Jianxiong3.& ZHAN Wenlong11. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 73.000, china 2. department of Physics, Xianyang Normal university, Xianyang 712000, china 3. department of Modern Physics, Lanzhou university, Lanzhou 73.000, china 4. department of Applied Physics, Xi’an Jiaotong university, Xi’an 710049, china 1. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. department of Physics Xianyang Normal University Xianyang 712000 China 3. department of Modern Physics Lanzhou University Lanzhou 730000 China 4. department of Applied Physics Xi’an Jiaotong University Xi’an 710049 China

By use of optical spectrum technology, the spectra of X-ray induced by highly charged 40Arq+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar16+ion, with electronic con-figuration 1s2 in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.

关键词： highly charged ion hollow multi-electron excitation X- ray.

Syntheses of Ferrierite and Mordenite Zeolites from Dried Gel in Alcoholic System

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Chemical Research in Chinese Universities 1995年第4期11卷 364-366页

作者： DU Hong-bin QIU Shi-lun and PANG Wen-qin(department of chemistry,jilin {3.,Changchun,13.023. jilin UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA

ＳｙｎｔｈｅｓｅｓｏｆＦｅｒｒｉｅｒｉｔｅａｎｄＭｏｒｄｅｎｉｔｅＺｅｏｌｉｔｅｓｆｒｏｍＤｒｉｅｄＧｅｌｉｎＡｌｃｏｈｏｌｉｃＳｙｓｔｅｍＤＵＨｏｎｇ－ｂｉｎ；ＱＩＵＳｈｉ－ｌｕｎａｎｄＰＡＮＧＷｅｎ－ｑｉｎ（Ｄｅ... 详细信息

ＳｙｎｔｈｅｓｅｓｏｆＦｅｒｒｉｅｒｉｔｅａｎｄＭｏｒｄｅｎｉｔｅＺｅｏｌｉｔｅｓｆｒｏｍＤｒｉｅｄＧｅｌｉｎＡｌｃｏｈｏｌｉｃＳｙｓｔｅｍＤＵＨｏｎｇ－ｂｉｎ；ＱＩＵＳｈｉ－ｌｕｎａｎｄＰＡＮＧＷｅｎ－ｑｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔ...

关键词： Synthesis Zeolite Mordenite Ferrierite Alcoholic system

Novel Properties of Supramolecular Complexes Formed by Pairing Cationic Porphyrin and Anionic Metal-Oxo Cluster

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Chinese Chemical Letters 2000年第9期11卷 831-834页

作者： Shu Qing LIU Ji Qing XU Hao Ran SUN department of chemistry, jilin {3., Changchun 13.023 jilin Univ Dept Chem Changchun 130023 Peoples R China

MTBPyP (meso-tetrakis(4-N-benzylpyridyl)porphyrin, M=H-2, Zn) bearing positive charge has been shown to associate with SiW12O404- in water solution. The spectral evolution and Job's plots analyses reveal that the rela... 详细信息

关键词： cationic porphyrin anionic metal-ore cluster ion pair supramolecular complex

A MESSAGE-DRIVING FORMALISM FOR MODELING AND SIMULATION OF MULTI-AGENT SUPPLY CHAIN SYSTEMS

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Journal of Systems Science and Systems Engineering 2011年第4期20卷 385-399页

作者： Wenzhe TAN1 Yueting CHAI2 Yi LIU3.1department of Automation, Tsinghua university, Beijing, 100084, china 2department of Automation, Tsinghua university, Beijing, 100084, china 3.0} of Automation, Tsinghua university, Beijing, 100084, china department of Automation Tsinghua University Beijing China

To acquire a competitive advantage in the expanding market, manufacturing enterprises should be able to manage their supply chains as effectively as possible. It is now becoming popular to model supply chains as multi-agent systems and use discrete event simulation to learn more about their behaviors or investigate the implications of alternative configurations. In order to enhance the computational efficiency and keep the simulation credibility, this paper proposes a message-driving formalism for the simulation of multi-agent supply chain systems. Through the message-driving formalism, the problem of shared variables is addressed and the parallel operation of agents is implemented. Simulation experiments with a prototype implementation show that the message-driving formalism is able to provide credible results in significantly less simulation time.

关键词： Supply chain multi-agent system modeling and simulation parallel discrete event simulation message-driving formalism

“有效降低全社会物流成本”研讨会专家观点综述

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中国流通经济 2024年第5期38卷 3-17页

作者：本刊编辑部《中国流通经济》编辑部

2024年2月24日,习近平总书记主持召开中央财经委员会第四次会议,指出物流是实体经济的“筋络”,强调必须有效降低全社会物流成本,增强产业核心竞争力,提高经济运行效率。基于此,2024年4月24日,北京物资学院党委宣传部、杂志社、科研处... 详细信息

2024年2月24日,习近平总书记主持召开中央财经委员会第四次会议,指出物流是实体经济的“筋络”,强调必须有效降低全社会物流成本,增强产业核心竞争力,提高经济运行效率。基于此,2024年4月24日,北京物资学院党委宣传部、杂志社、科研处联合主办了“有效降低全社会物流成本”研讨会。本次研讨会邀请我国流通物流领域的专家学者,围绕物流服务实体经济和人民群众、物流成本构成、交通运输体系改革、统一高效物流市场构建和现代商贸流通体系完善等问题,发表观点,为探索有效降低全社会物流成本可行路径,构建现代流通体系提供理论支持和实践指导。本刊编辑部对专家阐述的主要观点进行了归纳整理,以飨读者。

关键词：全社会社会物流成本新质生产力流通体系降本增效

Synthesis and Characterization of One-dimensional and Two-Dimensional Porphyrin Polymers (Ⅰ)

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Chemical Research in Chinese Universities 2001年第2期17卷 226-227页

作者： LI Xiang-qing, WANG Xing-qiao, GUO Jing-fu, MENG He and LJU Guo-fa (department of chemistry, jilin {3., Changchun 13.023. P. R. china) jilin Univ Dept Chem Changchun 130023 Peoples R China

A procedure for the synthesis of one-dimensional tetraaminophenylporphyrin (TAPP) was described. Quantitative infrared (IR) spectrum analysis of the monomer showed that it exhibited strong absorption at 1,621 cm-1. Results also indicated that the interaction between porphyrin macrocycles was enhanced after the metalloporphyrin linked up with the axial ligand. The degree of polymerization in [Mn(TPP)(pyz)]n was assessed using the ligand absorption rate.

关键词： Synthesis Porphyrin polymer Bipyridine Imidazole