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Journal of Central South university 2000年第1期12卷 29-33页

作者： LI Yuan gao,ZHANG Quan ru,FANG Zheng(college of chemistry and chemical {3.ing, Central South university of Technology, changsha 410083. china) college of chemistry and chemical {3.ing Central South University of Technology Changsha China

In order to calculate the activity coefficients of water in aqueous solution of metal electrolytes, a simplified model predicting them in ternary or multicomponent solutions with common anions from the activity data of water of the corresponding binary systems has been developed based on an assumption that the electrolytes in the solution are treated as independent particles instead of their ion forms, and the interaction of the salt( i ) salt( j ) pair in the solution is assumed to be much weaker than that of water salt pair due to the common anions of both of salts. The model was applied to the systems such as KCl H 2O NaCl, MCl H 2O M′Cl 2 (M represents Na and K, M′ represents Ca and Ba) and KCl H 2O NaCl BaCl 2 with satisfying results. The interchange energies of the studied component pairs between water and salts have also been determined by the corresponding binary aqueous solutions.

关键词： activity of water electrolyte thermodynamic model interchange energy

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

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Journal of Central South university 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 {3.ing, Central South university, changsha 410083. china) college of chemistry and chemical {3.ing Central South University 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

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

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Journal of Central South university 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 {3.ing, Central South university, changsha 410083. china 2 Hengyang Branch of hunan university, Hengyang 412000, china) college of chemistry and chemical {3.ing Central South University Changsha China Hengyang Branch of hunan university 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 200 250 ℃ 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, 3.0% 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

Upgrade and separation of Co from solution with low-grade Co

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中南工业大学学报：英文版 2001年第4期8卷 249-251页

作者： ZHONG Shi an,ZHOU Chun shan,OU Yang xi,CHENG Ben cheng(college of chemistry and chemical {3.ing, Central South university, changsha 410083. china) college of chemistry and chemical {3.ing Central South University Changsha China

Upgrade and separation of Co from solution with low grade Co were studied. In the solution, the content of Co is about 1 g·L -1 , while that of Ni, Zn, Mn, Mg, Si and Ca is 0.145, 1.108, 0.119, 6.672, 0.026 and 0.200 g·L -1 , respectively. After absorbed with absorbent G-1, the content of Co in the solution is less than 1 mg·L -1 , the average loss rate of Co is 0.07%, while the average loss rate of Mg is 67.92%. It is demonstrated that the absorbent has selectivity to absorb Co. After the absorbent was eluted with HCl at room temperature, the solution with higher content of Co was obtained. Through being evaporated and concentrated, the contant of Co in the solution can be upgraded to 26.6 g·L -1 . At the same time, most of Si, Mg is removed, the total recovery of Co can reach as high as 98.7%. The content of Pb, Ni, Cu, Zn, Mn in the discharge solution is 1.00, 0.26, 0.21, 0.09, 0.15 mg·L -1 , respectively, and the discharge solution can reach the national discharge standard. CoCl 2 solid can be obtained and can reach chemical purity.

关键词： Co upgrade separation

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 {3.ing, Central South university, changsha 410083. china 2.Department of chemical {3.ing, Yueyang Normal university, Yueyang 414000, china) college of chemistry and chemical {3.ing 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 ℃ for 24 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：不可溶解的尾 - cyclodextrin 聚合物毛状的煤气的层析 enantiomer 位置异构体分离

A novel gene carrier based on amino-modified silica nanoparticles

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Science Bulletin 2003年第3期48卷 223-228页

作者： HE Xiaoxiao, WANG Kemin, TAN Weihong, LIU Bin, LIN Xia, HUANG Shasheng, LI Du, HE Chunmei & LI Jun State Key Laboratory of Chemo/Biosensing and Chemometrics, college of chemistry & chemical {3.ing, Institute of Biological Technol-ogy, hunan university, changsha 410082, china State Key Laboratory of Chemo/Biosensing and Chemometrics Institute of Biological Technology Hunan University Changsha 410082 China

Uniform-sized amino-modified silica nanopar-ticles have been prepared by the controlled synchronous hydrolysis of tetraethoxysilane and N-(?amimoethyl)-- aminopropyltriethoxysilane in water nanodroplet of the wa-ter-in-oil microemulsion. These nanoparticles display posi-tive charge potential at definited pH. This is due to the pres-ence of amino groups on the surface of the nanoparticles. Nanoparticles-plasmid DNA complexes can easily form through electrostatical binding between the positive charges of the amino-modified silica nanoparticles and the negative charges of the plasmid DNA. The complexes can be also dis-sociated under alkaline pH or high ionic strength conditions. And enzymatic digestion of the plasmid DNA is almost in-hibited by these nanoparticles complexes. A novel non-viral gene carrier based on the amino-modified silica nanoparti-cles is proposed under the combination of nanotechnology, biotechnology and gene engineering technology. The plasmid DNA can successfully cross various systemic barriers to COS-7 cells as well as mediate high expression of Green Fluorescence Protein (GFP) gene in cells by use of this novel gene carrier.

关键词： gene carrier nanoparticle amino-modified silica.

Silylated and acetylated β-cyclodextrins for gas chromatographic stationary phases

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Journal of Central South university of Technology 2001年第4期8卷 239-243页

作者： TANG Ke wen 1,2 ,YI Jian ming 2,ZHOU Chun shan 1,ZHONG Shi an 1 (1. college of chemistry and chemical {3.ing, Central South university, changsha 410083. china 2. college of chemistry and chemical {3.ing, Yueyang Normal university college of chemistry and chemical {3.ing Central South University Changsha China college of chemistry and chemical {3.ing Yueyang Normal University Yueyang China

Two new chiral stationary phases, 2,3.di O acetyl 6 O trimethylsilyl β cyclodextrin (DATBCD) and 2,6 di O trimethylsilyl 3.O acetyl β cyclodextrin(DTABCD), were synthesized, their structures were identified by means of infrared and NMR spectra. Capillary columns were coated with the two stationary phases by dynamic method. The chromatographic properties, and enantiomers separation, such as ketone, esters, alcohols and olefines, were investigated on the silylated and acetylated β cyclodextrin stationary phases. The experimental results show that the silylated and acetylated β cyclodextrins are suitable to be used as capillary gas chromatographic stationary phases, the relative polarity of DATBCD and DTABCD stationary phases is respectively 4143.and 3.28, the column efficiencies are respectively 3.84 and 4198, and DATBCD is of stronger enantioselectivity than DTABCD, capacity factor of the first eluted enantiomer ( k 1) and separation factor(α)of α phenylethanol on DATBCD stationary phase are respectively 8.23.and 1.019.

关键词： capillary gas chromatography silylated and acetylated β-cyclodextrins enantiomeric separation

Preparation of 5N high purified indium by the method of chemical purification-electrolysis

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Rare Metals 2002年第2期21卷 137-141页

作者： ZENG Dongming, ZHOU Zhihua, SHU Wangen, LIU Younian, and HU Aipingcollege of chemistry and chemical {3.ing, Central South university, changsha 410083. china college of chemistry and chemical {3.ing Central South University Changsha 410083

The application of indium requires high purity indium as material.5N high purity indium had been prepared by the method of acombination of chemically smelting and electrolysis. Smelting timewas 10 min, the abstraction rate of cadmium was 80/100-90/100 whenused solution of I_2-KI and glycerine to smelt indium. 4N metalindium was used as anode, high purity indium as cathode, In-2(SO_4)_3.H_2SO_4 system as electrolyte, and In content is 100 g/L, pH2-3.and current density 80-100 a/m^2.

关键词： high-purify indium preparation chemical purifying

Preparation of chemical manganese dioxide from manganese sulfate

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Mining Science and Technology 2010年第6期20卷 877-881页

作者： FU Jiangang, HE Zhangxing, WANG Hui, LIANG Wei, GUO Chao college of chemistry and chemical {3.ing, Central South university, changsha 410083. china college of chemistry and chemical {3.ing Central South University Changsha 410083 China

chemical Manganese Dioxide (CMD) was prepared by an alkali-oxidation method. There are several virtues to this environmental friendly and clean process, including the nontoxic and harmless reagents and products, easy operations, no pollutants, easily obtained raw materials and moderate reaction conditions. The synthesized manganese dioxide was characterized by XRD and SEM. The particles were small, consisting primarily of α-MnO2 and γ-MnO2. Experimental results showed that the optimum conditions were: MnSO4?H2O to NaOH ratio, 1.0:2.4; catalyst concentration (catalyst TF-2), 6% of the MnSO4; initial solution pH, 11; reaction time and temperature, 20 min and 80 °C; air flow, 0.20 m3.h; and, agitation rate, 700 r/min. The conversion of MnSO4 can exceed 80% under these optimum conditions.

关键词：化学二氧化锰硫酸锰制备催化剂浓度 MnO2 最佳条件 X射线衍射初始pH值

Aspects of recent developments in analytical chemometrics

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Science china chemistry 2006年第3期49卷 193-203页

作者： LIANG Yizeng1,2, WU Hailong1, SHEN Guoli1, JIANG Jianhui1, LIANG Sheng2 & YU Ruqin1 1. State Key Laboratory of Chemo/Biosensing and Chemometrics, college of chemistry and chemical {3.ing, hunan university, changsha 410082, china 2. Research Center of Modernization of Traditional Chinese Medicines, Central South university, changsha 410081, china State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha China Research Center of Modernization of Traditional Chinese Medicines Central South University Changsha China

Some aspects of recent developments in analytical chemometrics are discussed, in par- ticular the developments viewed from the angle of the research efforts undertaken in authors’ labora- tories. The topics concerned include resolution of high-order chemical data, morphological theory and methodology for chemical signal processing, multivariate calibration and chemical pattern recognition for solving complex chemical problems, and resolution of two-way chemical data from hyphenated chromatographic instruments.

关键词： chemometrics, high-order chemical data, pattern recognition, multivariate calibration and resolution.