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Preparation of insoluble β-CD polymer and its application to enantiomers and isomers separation

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Journal of Central South university of Technology 2001年第1期8卷 57-59页

作者： YI Jian ming 1,TANG Kuo wen 2.(1.college of Chemistry and chemical {2., Central South university, Changsha 410083, China 2.Department of chemical {2., yueyang normal university, yueyang 414000, China) college of Chemistry and chemical {2. Central South University Changsha China Department of chemical engineering Yueyang Normal University Yueyang China

An insoluble β-cyclodextrin polymer cross-linked with epichlorohydrin was prepared, and its structure was identified with infrared spectrum. Colloid stationary phase was prepared by dissolving the polymer in the mixed solvent of diisopropyl ether, methylene dichloride and benzene and treated for 0.5 h by ultrasonication, and then was coated on a fused silica capillary column. The optimun reaction conditions are as follows: the mole ratio of epichlohydrin to β-cyclodextrin is 12.1:1, reacting at 65 °C for 2. h. The Chromatographic performance such as column efficiency, thermal stabilities and polarity were studied, two kinds of disubstituted benzene isomers and eight pairs of enantiomers were separated on the capillary column. The results show that the β-cyclodextrin polymer is suitable for use as a capillary gas chromatographic stationary phase, and possess excellent chromatographic properties in separating enantiomers and position isomers.

关键词： insoluble β cyclodextrin polymer capillary gas chromatography enantiomer position isomer separation

A Series Piezoelectric Quartz Crystal Response Kinetics for *** Growth in the Presence of Cu(Ⅱ)

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Journal of Central South university 2000年第1期12卷 15-19页

作者： CHAI Li yuan 1,2.,WEI Wan zhi 2.YAO Shou zhuo 2.1. Department of Metallurgical Science and engineering, Central South university of Technology, Changsha 410083, China 2. {2. of Chemistry and chemical engineering, Hunan university, Changsha Department of Metallurgical Science and engineering Central South University of Technology Changsha China college of Chemistry and chemical {2. Hunan University Changsha China

The kinetics on the growth of *** in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of *** , which is consistent with the previous results by other measuring methods. This further demonstrates that the SPQC can monitor the chemical activity of *** growth. Cupric ion accelerates the growth of *** . The mechanism was discussed, i. e., copper promotes the protein enzyme of *** , rusticyanin, to form over the range of cupric ion concentration studied. The reaction order of cupric ion in accelerating the bacterial growth is 0.067. The growth of *** is dependent on temperature, the apparent reaction activation energy decreases from 2..56 kJ/mol to 18.32.kJ/mol because of the addition of 10 mg/L Cu(Ⅱ) to the bacterial growth solution of pH 2.0 at initial inoculum of 10%.

关键词： series piezoelectric quartz crystal T.ferrooxidans growth kinetics sigmoid curve cupric ion

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 China normal {2., Wuhan 430079, P. R. China 2. college of Chemistry and chemical engineering, Luoyang normal {2., Luoyang 47102., P. R. China School of Chemistry Central China Normal University Key Laboratory of Pesticide & Chemical Biology Ministry of Education Wuhan 430079 college of Chemistry and chemical {2. 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

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 college of Chemistry and Molecular engineering Qingdao University of Science and Technology Qingdao China college of Chemistry and chemical {2. Ocean University of China 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 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

Extraction of vegetation fraction information from CBERS images based on VBSI vegetation index in Kaixian county

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中国有色金属学会会刊：英文版 2011年第S3期21卷 712-716页

作者： GAO Zhi-fang1, NIU Hai-peng1, LIU Jin-ping2.1. college of Surveying and Land Information engineering, Henan Polytechnic {2., Jiaozuo 454000, China 2. college of Geographic Sciences, Chongqing normal {2., Chongqing 400047, China college of Surveying and Land Information engineering Henan Polytechnic University Jiaozuo 454000 China college of Geographic Sciences Chongqing Normal University Chongqing 400047 China

Based on the mixed pixel model, the vegetation fraction of Kaixian county, China, was extracted with three free CBERS images. VBSI vegetation index suitable for CBERS images constructed with FCD (forest canopy density) model principle was put forward by ITTO (International Tropical Timber Organization) was used, considering the underestimation of vegetation fraction using NDVI in low mountain-hill region influenced by soils and shadows. And vegetation fraction was divided into five categories from low to high in order to study the special variation of vegetation cover. The results show that the vegetation cover of the region is overall good, with an average of 50%. The area of vegetation fraction below 30% accounts for 11.7% of the entire studied area, mainly concentrates in central eastern Kaixian county, where is the major development zone of cities and towns; that between 30% and 60% accounts for 62.; and that higher than 60% accounts for 2.%, and mostly locates in northern middle-mountain area.

关键词： VBSI vegetation index mixed pixel model FCD model CBERS

Nonequilibrium solvation theory:Comparison,modification and application

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Chinese Science Bulletin 2003年第10期48卷 965-970页

作者： FU Kexiang1,2. LI Xiangyuan1 & ZHU Quan1 1. college of chemical {2., Sichuan university, Chengdu 610065, China 2. college of Physics, Sichuan university, Chengdu 610065, China college of chemical {2. Sichuan University Chengdu China college of Physics Sichuan University Chengdu China

Faults existing in the current theories of non- equilibrium solvation have been clarified in this report. Based on a novel expression of solvation free energy for nonequilibrium, generalized formulations of solvent reor- ganization energy for electron transfer and of solvation shift for spectrum have been established. Furthermore, a new form of solvent reorganization energy for electron transfer in two-sphere case, which greatly differs from the one by Mar- cus, has been deduced. A single-sphere model for solvation shift of spectrum has been put forward both by deducing the generalized formulations and by showing the correct forms of self-energy of reaction field. It has been concluded that the current theories overestimate the solvent reorganization energy and the solvation shift by a factor of about 2. By apply- ing the models established, the discrepancies between the theory and experiments before have been perfectly explained.

关键词：非平衡溶剂理论修正应用电子转移溶剂重构能量反应场溶剂交换

Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG Shi-dong1, 2. LIU Chang-hua2. ZHANG He-bing2.1. college of Resources Science and Technology, Beijing normal {2., Beijing 100875, China 2. School of Surveying and Land Information engineering, Henan Polytechnic {2., Jiaozuo 454000, China college of Resources Science and Technology Beijing Normal University Beijing 100875 China School of Surveying and Land Information engineering Henan Polytechnic University Jiaozuo 454000 China

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine

Fuzzy controllers based on some fuzzy implication operators and their response functions

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Progress in Natural Science:Materials International 2004年第1期14卷 16-21页

作者： LI Hongxing 1*, YOU Fei 1 and PENG Jiayin 2.1. Department of Mathematics, Beijing normal university, Beijing 100875, China 2. Department of Mathematics, Neijiang Teacher's {2., Neijiang 641112. China) Department of Mathematics Beijing Normal University Beijing 100875 China. Department of Mathematics Neijiang Teacher''s College Neijiang 641112 China

The fuzzy controllers constructed by 2. fuzzy implication operators based on CRI algorithm and their response functions are discussed. The conclusions show that the fuzzy controllers constructed by 9 fuzzy implication operators are universal approximators to continuous functions and can be used in practical fuzzy control systems. And these 9 fuzzy implication operators except for Einstein operator intersection are all the adjoint pairs of some fuzzy implication operators. Besides, there are 3 other fuzzy controllers formed by fuzzy implication operators being regarded approximately as fitted functions.

关键词： fuzzy implication operators CRI algorithm fuzzy controllers response functions universal approximators

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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Wuhan university Journal of Natural Sciences 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2.1. Department of chemical engineering, Wuhan {2. of Technology, Wuhan 430070, Hubei, China 2. college of Chemistry and Molecular Sciences, Wuhan {2., Wuhan 430072. Hubei, China Department of chemical engineering Wuhan University of Technology Wuhan Hubei China college of Chemistry and Molecular Sciences Wuhan University Wuhan Hubei China

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization