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Synthesis, Crystal Structures and Catalysis of Dinuclear Cd(Ⅱ) Complexes Bridged by Unusual (N,O,O′)-Coordinated α-Amino Acids

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Chemical Research in Chinese Universities 2012年第1期28卷 73-78页

作者： DENG Dong-sheng1,2. WANG Li1, PEI Ya-mei1, FENG Lu2.and LIU Chang-lin1 1. Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, School of chemistry, central{2. Normal university, wuhan 430079, P. R.{2. 2. college of chemistry and Chemical Engineering, Luoyang Normal university, Luoyang 47102., P. R.{2. School of chemistry Central China Normal University Key Laboratory of Pesticide & Chemical Biology Ministry of Education Wuhan 430079 college of chemistry and Chemical Engineering Luoyang Normal University Luoyang 471022

Four dinuclear amino acid cadmium（II） complexes [Cd2.tren）2.dl-alaninato）]（ClO4）3·H2.（I）, [Cd2.tren）2. （l-alaninato）]（ClO4）3·H2.（II）, [Cd2.tren）2.dl-phenylalaninato）]（ClO4）3（III） and [Cd2.tren）2.l-phenylalaninato）]· （ClO4）3（IV）, constructed from mixed ligands of tris（2.aminoethyl）amine（tren） and racemic or natural amino ac ids（amino acids=dl or l-alanine, and dl or l-phenylalanine）, have been synthesized and characterized by X-ray crys tallography. The structural analysis of complexes I and III reveals that the cadmium centers are coordinated by one tren ligand and one amino acid molecule with the unusual （N,O,O′）-bridged mode, resulting in asymmetric chromo phores of CdN4O and CdN5O in complex I, CdN4O2.and CdN5O in complex III, respectively. The utility of the four complexes as efficient water-compatible Lewis acid catalysts for the direct aldol reaction in water was examined. The reaction proceeded smoothly to afford the corresponding β-hydroxy ketones in up to 99% yield. Moreover, the dias tereoselectivity of the reaction favors the formation of the syn-isomers.

关键词： Dinuclear cadmium(II) complex Amino acid Aldol reaction

Effect of lead on survival, locomotion and sperm morphology of Asian earthworm, Pheretima guillelmi

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Journal of Environmental sciences 2009年第5期21卷 691-695页

作者： ZHENG Rongquan, LI Canyang college of chemistry and {2. Science, Zhejiang Normal university, Jinhua 32.004, china. [a]college of chemistry and {2. Science Zhejiang Normal University Jinhua 321004 China

To provide basic toxicity data for formulating risk characterization benchmarks, the effects of lead on survival, locomotion, and sperm morphology were investigated in the Asian earthworm Pheretima guillelmi. The LC50 of P. guiUelmi for 7 and 14 d were 42.5＋339 mg/kg and 32.7＋2.8 mg/kg, which shows P. guillelmi can tolerate a higher concentration of lead nitrate. The average weight of the surviving earthworms decreased at concentration of 2.00 mg Pb/kg soil, and the locomotor ability of earthworms exposed to a range of soil Pb concentrations showed a general decrease with increasing Pb concentrations. We also presented data depicting the sperm morphology of earthworms, which shows potential as a sensitive biomarker for measuring the effects of heavy metal on reproduction.

关键词： lead Pheretima guillelmi sperm morphology locomotion

A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2.F film optically transparent electrode

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Science china chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2.& NIU Shuyan1,2.1. college of chemistry and Molecular Engineering, Qingdao {2. of Science and Technology, Qingdao 2.6042. china 2. college of chemistry and Chemical Engineering, Ocean {2. of china, Qingdao 2.6003, china Correspondence should be addressed to Jiao Kui 1. college of chemistry and Molecular Engineering Qingdao University of Science and Technology 266042 Qingdao China 2. college of chemistry and Chemical Engineering Ocean University of China 266003 Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2.F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to < 4.0, and two successive one-electron electrooxidation processes in the pH range from 4.0 to < 7.0 in the B-R buffer solution. At pH 6.5, the electrooxidative product of TMB generated a subsequent chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

Synthesis and properties of nickel borate acylate as a new rubber-steel cord adhesion promoter

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Journal of central south {2. of Technology 2001年第4期8卷 244-248页

作者： LI Xiao ru 1,NIE Xi du 2.WU Hai ying 1,CHENG Ben cheng 1 (1 college of chemistry and Chemical Engineering, {2. south university, Changsha 410083, china 2.Hengyang Branch of Hunan university, Hengyang 412.00, china) 1. college of chemistry and Chemical Engineering Central South University 410083 Changsha China 2. Hengyang Branch of Hunan university 412000 Hengyang China

The synthetic method of nickel borate acylate (NBA), a kind of rubber steel cord adhesion promoter (AP), through nickel carbonate, borate and mixed carboxylic acid was studied. The preparation of nickel carbonate could be performed through reaction of nickel sulfate with sodium carbonate in aqueous solution, in which fractional conversion of nickel was more than 99.9%. The mixed nickel carboxylate was prepared by the reaction of nickel carbonate with isooctanoic acid and acetic acid, under strong stirring for 2.h, the mole ratio of these chemicals were 1∶1∶1.1 respectively, and water should be removed completely by adding of inert organic solvent after reaction was finished so as to avoid hydrolysis of tributyl borate in the second reaction. NBA was synthesized by reaction of mixed nickel carboxylate with tributyl borate under strong stirring at 2.0 2.0 ℃ for 6 h. By detection and comparison with 680C product from Manobond Company of England, the NBA synthesized through isooctanoic acid and tributyl borate was very similar to product 680C in IR data, 300% fixed extension strength, tensile strength, hardness and cure curve, and was slightly lower than those of product 680C in tensile failure extensibility and hot air aging. The experimental results show that the prepared NBA can be used as rubber steel cord AP.

关键词： nickel borate acylate adhesion promoter nickel carbonate borate

Proton Conducting Composite Membranes from Sulfonated Polyether Ether Ketone and SiO_2

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Journal of wuhan university of Technology(Materials Science) 2009年第1期24卷 95-99页

作者：张高文 college of chemistry and Environment Hubei University of Technology

Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2.for direct methanol fuel cell （DMFC） application were prepared with sulfonated polyether ether ketone（SPEEK） and tetracethoxy silane（TEOS） by sol-gel method. The covalent crosslinking structure was formed between —SO3H of SPEEK via SiO2. The SEM images show that the interfacial compatibility of SPEEK and SiO2.is improved obviously and SiO2.disperses uniformly in the polymer matrix and the particle diameter of SiO2.does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO3H and SiO2..

关键词： direct methanol fuel cell sulfonated polyether ether ketone sol-gel method proton conductivity methanol permeability

Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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Science china chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. chemistry and Chemical Engineering college of Henan {2., Kaifeng 475001, china 2. Changchun Institute of Applied chemistry, Chinese Academy of sciences, Changchun 13002., china 1. chemistry and Chemical Engineering college of Henan {2. Kaifeng 475001 China 2. Changchun Institute of Applied chemistry Chinese Academy of Sciences Changchun 130022 China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

Extended detection range for an optical enzymatic glucose sensor coupling with a novel data-processing method

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Science china chemistry 2010年第6期53卷 1385-1390页

作者： GUO GuangMei1,WANG XuDong2.ZHOU TingYao2.& CHEN Xi2.1college of sciences,Hebei {2. of Science and Technology,Shijiazhuang 050018,china 2.epartment of chemistry,college of chemistry and Chemical Engineering,Xiamen {2. Key Laboratory of Analytical sciences of Xiamen {2.,Xiamen 361005,china 1. college of sciences Hebei University of Science and Technology Shijiazhuang 050018 China2. Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Key Laboratory of Analytical sciences of Xiamen university Xiamen 361005 China

A new data-processing method was established and applied for optical enzymatic glucose sensing,in which oxygen and glucose were simultaneously *** oxygen level remaining in the detection system,which was equal to the difference between the initial and consumed oxygen concentrations,could be measured using fluorescent oxygen indicators immobilized in the sensing *** was deduced that the ratio of I0 and I was inversely proportional to glucose concentration,where I0 is the maximum fluorescence intensity in various glucose solutions,and I is the fluorescence intensity at various concentrations of *** the new data-processing method,the detection range of the calibration curve method was extended from 0 to 1.2.mmol L-1,which was enlarged about 2.3 folds over that in ordinary *** prepared glucose sensor could be directly applied to detect high concentrations of glucose.

关键词： optical glucose sensor glucose oxidase extended detection range

Immunomagnetic assay combined with CdSe/ZnS amplification of chemiluminescence for the detection of abscisic acid

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Science china chemistry 2011年第8期54卷 1298-1303页

作者： ZHOU GuoHua, WANG Ping, YUAN Ju, QIU Ting & HE ZhiKe Key Laboratory of Analytical chemistry for Biology and Medicine, Ministry of Education college of chemistry and Molecular sciences, wuhan university, wuhan 430072. china 1. Key Laboratory of Analytical chemistry for Biology and Medicine Ministry of Education college of chemistry and Molecular {2. Wuhan University Wuhan 430072 China

Abscisic acid (ABA) is an important plant hormone. It plays a key role in regulating plant responses to abiotic stress and in controlling seed germination, growth, and stomatal aperture. A rapid, sensitive analytical method for the ABA detection is urgently required for further investigation of ABA signaling. In this work, an immunomagnetic assay combined with CdSe/ZnS amplification of chemiluminescence has been developed for the detection of ABA. The result could be read out in 30 min at least, with the simplified procedure of immunomagnetic assay. Under the optimized condition, a linear range from 1 pM to 10 nM was obtained. An unexpected result induced by the dose hook effect was discussed. This method provided the high selectivity for ABA over other components that might be contained in real samples.

关键词： abscisic acid immunomagnetic assay chemiluminescence CdSe/ZnS

Synthesis of p-nitrophenol under normal pressure with A-1 phase transfer catalysis

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Journal of central south {2. of Technology 2001年第1期8卷 54-56页

作者： ZHONG Shi an, OUYANG Xi, ZHOU Chun shan, CHENG Ben cheng (college of chemistry and Chemical Engineering, {2. south university, Changsha 410083, china) 1. college of chemistry and Chemical Engineering Central South University 410083 Changsha China

p nitrophenol is synthesized using p nitrochlorobenzene and sodium hydroxide with phase transfer catalyst. Several reaction factors, such as catalyst type, the amounts of catalysts and sodium hydroxide, the concentration of sodium hydroxide solution as well as reaction time, affect greatly the yield of p nitrophenol. The optimum reaction conditions are as follows: A 1 used as phase transfer catalyst whose consumption is 6% (mole fraction) of p nitrochlorobenzene; the molar ratio of sodium hydroxide to p nitrochlorobenzene is 3:1; the concentration of sodium hydroxide solution is 50% (mass fraction). Nitrobenzene, whose molar amount is 2.45 times as much as that of p nitrochlorobenzene; reaction time is 7 h at 140 ℃ under normal pressure. The final yield of p nitrophenol is 83.6%.

关键词： phase transfer catalysis p nitrophenol synthesis