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Enantioselective reduction of acetophenone analogues using carrot and celeriac enzymes system

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Chinese Chemical Letters 2010年第3期21卷 305-308页

作者： liu, Xiang Pan, Zheng Guang Xu, Jian he li, he xing Jiangnan Univ Sch Chem & Mat Engn Wuxi 214122 Peoples R China E China Univ Sci & Technol State Key Lab Bioreactor Engn Shanghai 200237 Peoples R China Shanghai Normal Univ Dept Chem Shanghai 200234 Peoples R China

The enantioselective reduction of acetophenone analogues catalyzed by carrot and celeriac was performed in moderate conversions and excellent enantiomeric *** steric factors and electronic effects of the substituents at the aromatic ring were found to significantly affect the efficiency of the enantioselective reduction of acetophenone analogues,while they had a little effect on the enantioselectivity of acetophenone analogues *** was also found that the conversions of acetophenone analogu...

关键词： Enantioselective reduction Acetophenone analogues Plant cells Biocatalysis

Electrochemical studies of chloroperoxidase on poly-L-lysine film modified GC electrode

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Chinese Chemical Letters 2010年第1期21卷 93-96页

作者： Zhao, Wen Wu, Xia Qin Lu, Zhong Qing Hou, Wen Jing li, he xing Shanghai Normal Univ Life & Environm Sci Coll Shanghai 200234 Peoples R China

Poly-L-lysine(PLL) was first electrodeposited onto the surface of a glassy carbon(GC) *** PLL modified electrode was used to immobilize chloroperoxidase(CPO) via 1-[(3-dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride(EDC).The electrochemical behaviors of immobilized CPO on PLL/GC electrode were investigated by cyclic voltammetry(CV).The CV results obtained showed that CPO was successfully immobilized on the PLL/GC electrode and a fast direct electron transfer between CPO and PLL-GC electrod...

关键词： Chloroperoxidase Poly-L-lysine Electrodeposition Electrocatalysis Direct electrochemistry Modified electrode

The Promoting Effect on the Activities ofFe Doped TiO_2 Photocatalysts

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Chemical Research in Chinese Universities 2001年第2期17卷 187-192页

作者： YU Xi-bin, WANG Gui-hua and li he-xing (Department of Chemistry, Shanghai Normal University, Shanghai 200234, P. R. China) 上海师范大学上海 200234

The particles of titanium-iron (Ti/Fe) complex with different Fe contents were prepared by means of the sol-gel method and used as a photocatalyst. The activity of the catalyst was investi- gated as a function of the Fe content during the liquid-phase oxidation of tetracycline, which showed an enhancement at the low Fe content. The XRD, Raman, XPS, and UV-Vis absorp- tion spectra indicated that the crystalline structure of the Ti/Fe complex particles changed from anatase phase to rutile phase when the Fe content increased. The isolated Fe203, Fe304, FeO species were observed and Fe3+ ions were highly dispersed in the TiO2 matrixes, then Ti-O-Fe species were formed. These species increased the surface defects of the Ti/Fe particles. Also, ac- tive hydroxyl radicals could be generated in the catalytic transformation, which led to the higher activity of the catalyst than bare Ti02 for the degradation of tetracycline.

关键词： Titanium Fe doped photocatalyst Photocatalytic activity Tetracycline

Surface Modification and Model of Glassy Cementitious Materials

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Wuhan University Journal of Natural Sciences 2000年第4期5卷 491-496页

作者： Ma Bao-guo, li Yong-xin, he xing-yang, Chen You-zhi College of Materials Secience and Engineering,Wuhan University of Technology Wuhan, 430070,China College of Materials Secience and Engineering Wuhan University of Technology Wuhan China

Basic theory of surface modification about glassy cementitous materials is presented. At the same time modified glassy cementitous materials were manufactured by means of point activation and disperse and grind aid according to technology of mechanical-chemistry. This theory about surface modification has been proved by some experimental results such as SEM, size distribution, fluidity of the paste, physical-mechanical properties of the hardened paste and heat of the hydration. The particle size of modified fly ash is tending to become smaller and the shape of microfine particles seems a ball; strength of modified glassy cementitous materials and ordinary portland cement compound paste has a obvious increment and fluidity of the paste also has a noticeable improvement; surface modification also can accelerate the formation of paste structure to a certain degree. Besides a model about the interactive mechanism of modified glassy cementitous materials and ordinary portland cement is put forward.

关键词： glassy eementitous materials surface modification point activation grind aid model

In/SBA-15催化剂的一步法制备及其在水介质中Barbier反应中的应用

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化学学报 2007年第16期65卷 1578-1582页

作者：熊明文李辉李和兴上海师范大学化学系上海200234

采用金属In的石蜡溶液浸渍载体,一步法制备具有介孔结构的In/SBA-15催化剂.在水介质中苯甲醛与烯丙基溴的Barbier反应中,发现负载量为w(In)=13%的In/SBA-15的催化活性显著高于金属In颗粒催化剂,而选择性相似,目标产物1-苯基-3-丁烯基-1... 详细信息

采用金属In的石蜡溶液浸渍载体,一步法制备具有介孔结构的In/SBA-15催化剂.在水介质中苯甲醛与烯丙基溴的Barbier反应中,发现负载量为w(In)=13%的In/SBA-15的催化活性显著高于金属In颗粒催化剂,而选择性相似,目标产物1-苯基-3-丁烯基-1-醇的得率可达89.2%.In/SBA-15的高活性主要归因于In活性位在SBA-15上的高分散,以及规整的介孔结构有利于反应物分子的扩散.同时,金属In与SBA-15间较强的相互作用也可稳定In活性位,显示出良好的应用潜力.

关键词： In/SBA-15 Barbier反应介孔结构水介质

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De he Yun-Lei Luo Qiu-Quan Pan Qi-Wei Yao xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Isolation and Purification of Myxobacteria in Chengdu

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Animal Husbandry and Feed Science 2011年第1期3卷 25-27页

作者： liU Bing-hua YANG lin FENG li-fu he liu-xing School of Medicine and Nurse Chengdu University Chengdu 610015 China

[ Objective] To lay the basis for further studying bioactive substances in myxobacteria. [ Method] A total of 35 samples including fresh water, mud, rabbit dung, sheep dung, weathered rock and rotten wood were collected from districts and counties of Chengdu. After pretreatment, the myxobacteria were isolated and purified using different methods. Vegetative cells, myxospores, fruiting body and colony morphology of these myxobacteria strains were observed. E ResultJ Forty-two myxobacteda strains were isolated and purified. They were classified into seven genera including Myxococcus, Angiococcus, Chondromyces, Sorangium, Melittangium, Stigmatella and Archangium. The plating efficiency of myxobacteria was highest in the fresh water samples. [ Conclusion] Abundant myxobacteria resource is found in fresh water.

关键词： Myxobacteria Isolation Purification Strains

Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 329-355页

作者： Yufeng xing Ye Yuan Gen li Institute of Solid Mechanics Beihang University(BUAA)Beijing100191China

The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical *** taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue ***,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are *** is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.

关键词： Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method

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《祝福》主题新解

教学与管理 2019年第16期 42-45页

作者：李兴和安徽省蒙城县第一中学

关于鲁迅小说《祝福》的主题,目前较为常见或较为主流的概括,便是“封建四权论”“礼教吃人论”等。对比这些貌似正确实则语焉不详的解读,教学中如果能够立足于文学文本的整体观照,遵循文学创作的基本规律,便能找到真实而又准确的答案,... 详细信息

关于鲁迅小说《祝福》的主题,目前较为常见或较为主流的概括,便是“封建四权论”“礼教吃人论”等。对比这些貌似正确实则语焉不详的解读,教学中如果能够立足于文学文本的整体观照,遵循文学创作的基本规律,便能找到真实而又准确的答案,从而给人耳目一新的视角——小说深刻揭示了封建思想和封建礼教与生俱来的本质属性就是其虚伪性和极端欺骗性,正是其虚伪性和极端欺骗性所形成的残酷的精神虐杀,才是造成祥林嫂悲剧人生的终极原因。

关键词：祝福主题虚伪性欺骗性