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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 university of Science and Technology, Qingdao 266042, China 2. college of Chemistry and chemical engineering, Ocean university of China, Qingdao 266003, 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 engineering 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

Influences of Ti substitution on the structure and electrochemical properties of Mg_(1-x)Ti_xNi(x=0,0.1, 0.2, and 0.3) hydrogen storage alloys

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Rare Metals 2009年第5期28卷 504-510页

作者： HUANG Hongxia HUANG Kelong LIU Suqin CHEN Dongyang college of Chemistry and chemical engineering Central South University Changsha 410083 China Department of Materials and chemical engineering Guilin University of Technology Guilin 541004 China

MgNi-based hydrogen storage alloys Mg1–xTixNi （x = 0, 0.1, 0.2, and 0.3） were prepared by means of mechanical alloying. Mg in the alloy was partially substituted by Ti to improve the cycle stability of the alloys. The effects of the substitution of Ti for Mg on the microstructure and electrochemical performances of the alloys were investigated in detail. The results indicate that the substitution of Ti for Mg obviously decreases the discharge capacity, but it significantly improves their cycle stabilities. The microstructure of the alloys analyzed by X-ray diffraction （XRD） and scanning electron microscopy （SEM） shows that the alloys have a dominatingly amorphous structure. The substitution of Ti for Mg helps to improve the anti-oxidation/corrosion ability of the MgNi alloy but demolishes the electrochemical kinetics of hydrogenation/dehydrogenation. The Mg0.9Ti0.1Ni alloy electrode milled for 80 h exhibits the best integrative capability, which has the maximal discharge capacity of 331.66 mAh/g and the C30/Cmax of 63.65%.

关键词： hydrogen storage alloys Ti substitution structural characteristic electrochemical properties

Preparation and microstructure of CuO-CoO-MnO/SiO2 nanocomposite aerogels and xerogels as catalyst carriers

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Progress in Natural Science:Materials International 2011年第4期21卷 330-335页

作者： Yue-qing ZHAO~1,Ying-hua LIANG~2,Xi-zhe ZHAO~3,Qian-yi JIA~4,Hong-sheng LI~4 1.college of Light Industry,Hebei United university,Tangshan 063000,China 2.college of chemical engineering,Hebei United university,Tangshan 063009,China 3.college of Printing and Packaging engineering,Beijing Institute of Graphic Communication,Beijing 102600,China 4.college of Materials Science and engineering,Hebei United university,Tangshan 063009,China college of Light Industry Hebei United University Tangshan 063000 China college of chemical engineering Hebei United University Tangshan 063009 China college of Printing and Packaging engineering Beijing Institute of Graphic Communication Beijing 102600 China college of Materials Science and engineering Hebei United University Tangshan 063009 China

CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were prepared using tetraethyl orthosilicate（TEOS） as Si source,and aqueous solution of Cu,Co and Mn acetates as the precursor via sol-gel process,CO2supercritical drying（SCD） technique or ambient pressure drying *** microstructure of the CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were characterized by field emission scanning electron microscopy（FE-SEM）,transmission electron microscopy（TEM） and X-ray diffraction（XRD）.The specific surface area,pore size and pore size distribution of the nanocomposite aerogels and xerogels were determined by the Brunauer-Emmett-Teller（BET） *** results showed that CuO-CoO-MnO/SiO2nanocomposite aerogels are porous,with a pore size distribution of 2-50 nm,an average pore size of 19.4 nm,a specific surface area of 384.9 m2/g and a particle size distribution of 10-150 nm,whereas the pore size distribution of CuO-CoO-MnO/SiO2composite xerogels is 1.7-128.6 nm,the average pore size is only 9.9 nm,the specific surface area is only 99.1 m2/g,and the particle size distribution is 100-500 *** structure of CuO-CoO-MnO/SiO2nanocomposite aerogels is favorable to increase the loading of catalysts.

关键词： composite aerogel composite xerogel catalyst carrier preparation microstructure

Spectrophotometric Investigation of Cadmium Complex Solutionwith m-Bromobenzenediazoaminoazobenzene

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Chinese chemical Letters 1999年第11期10卷 957-960页

作者： Hong Wen GAO Lei WANG Hao YE(School of Chemistry and chemical engineering, Anhui university, Hefei 230039)(Department of Chemistry, Huaibei Coal Teachers college, Huaibei 235000) Sch. of Chem. and Chem. engineering Anhui University Hefei 230039 China Department of Chemistry Huaibei Coal Teachers College Huaibei 235000 China

The synthesis of a new ligand, m-bromobenzenediazoaminoazobenzene (m-BBDA) was carried out. The reaction between m-BBDA and cadmium(II) was sensitive at pH over 12 and in the presence of emulsifier OP. Because of the high interference of excess of ligand beta-correction theory was applied instead of the single wavelength method. This study gave the simple determination of the complex ratio, real molar absorptivity (epsilon) and step or cumulative stability constant (K).

关键词： beta-correction principle cadmium complex m-bromobenzenediazoaminoazobenzene

Synthesis and Characterization of Polyaniline in Magnetic Field

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Journal of Wuhan university of Technology(Materials Science) 2008年第3期23卷 316-318页

作者：马利 college of Chemistry and chemical engineering Chongqing University

Polyaniline was obtained by chemical oxidation in the microemulsion system consisting of aniline, emulsifier, assistant emulsifier and water in magnetic field （0 T, 0.2 T, 0.4 T, 0,6 T）. The effect of magnetic field on the polymerization rate and the inherent viscosity of polyaniline were studied. The molecular structure of polyaniline was characterized by IR spectra and the thermal degradation behavior was assessed using TG techniques. The results show that the polymerization rate, molecular weight, thermal stability and conductivity of the synthesized polyaniline enhanced and no effect on the basic structural units of polyaniline was observed in magnetic field, Within the range of the intensity of magnetic field studied, the magnetic field of 0.4 T exerts the largest influence on polymerization of aniline.

关键词： magnetic field polyaniline microemulsion polymerization conductivity

Synthesis of LaFeO_3 catalytic materials and their sensing properties

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Science China Chemistry 2009年第12期52卷 2106-2113页

作者： BAI ShouLi,SHI BingJie,MA LiJing,YANG PengCheng,LIU ZhiYong,LI DianQing & CHEN AiFan State Key Laboratory of chemical Resource engineering,college of Science,Beijing university of chemical Technology,Beijing 100029,China State Key Laboratory of chemical Resource engineering College of Science Beijing University of Chemical Technology Beijing China

LaFeO3 is a p-type semiconductor catalytic material of perovskite structure (ABO3). Its magnetic and photocatalytic properties have been widely investigated,but the gas sensing properties are seldom reported,especially for toxic and noxious gases of NO2 and CO. The nanocomposites of LaFeO3 and LaFe1-xMgxO3 (x = 0.02,0.04,0.06) were prepared by various methods of the wet chemical process and their exact composition,crystal structures,grain sizes,specific surfaces,morphology and the electronic interaction between components were characterized by EDX,XRD,BET,SEM and XPS analysis. The sensors based on these nanocomposites have been fabricated to examine the sensing responses to gases,and the results show that these sensors exhibited high response to both oxidizing gas (NO2) and reducing gas (CO),and the response was greatly enhanced by the surface modification of MgO. The additive method,amount of additives,and their effects on the LaFeO3 structure and gas response have been analyzed and discussed by temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopic (XPS) analysis.

关键词： LaFeO3 NO2 CO sensing properties MgO-modified

Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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Science China Chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2, ZHANG GuoLi2, HUANG KeLong2, LI Yuanjian3 & YI JianMin1,2 1 Department of Chemistry and chemical engineering, Hunan Institute of Science and Technology, Yueyang 414000, China 2 college of Chemistry and chemical engineering, Central South university, Changsha 410083, China 3 college of Pharmaceutical Science, Central South university, Changsha 410078, China Department of Chemistry and chemical engineering Hunan Institute of Science and Technology Yueyang China college of Chemistry and chemical engineering Central South University Changsha China college of Pharmaceutical Science Central South University Changsha China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2-dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 27.6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

Studies on the composition and photometric properties of the heteropolyacid ion-associate Crystal Violet-molybdophosphate in various media

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Acta Chimica Sinica(English Edition) 1984年第1期2卷 46-52页

作者： ZHENG Yong-Xi Department of Chemistry and chemical engineering,Tsinghua university,Beijing WANG Zhen-Di Center of chemical Analysis,Nanjing Technological college of Forest Products,Nanjing Department of Chemistry and chemical engineering. Tsinghua university Beijing Center of chemical Analysis Nanjing Technological College of Forest Products Nanjing

In this paper,the photometric properties of the heteropolyacid ion-associate CrystalViolet-molybdophosphate in various media have been studied and its composition has been estab-lished as(C25H30N3)3·(PMo12O40)by means of spectrophotometry,elemental analysis and infraredabsorption *** has been proved that the photometric properties of the ion-asso-ciate depend mainly upon the cation of the basic *** have also compared the suspension（orcentrifugation）separation-organic solvent dissolution method,the micelle solubilization methodand the soluble polymer protection method.

关键词： Studies on the composition and photometric properties of the heteropolyacid ion-associate Crystal Violet-molybdophosphate in various media

Study on interaction between macrocell and microcell in the early corrosion process of reinforcing steel in concrete

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Science China(Technological Sciences) 2010年第5期53卷 1285-1289页

作者： LI LanQiang1,DONG ShiGang1,WANG Wei2,HU RongGang1,DU RongGui1,LIN ChangJian1,ZHUO XiangDong1 & WANG Jia2 1 State Key Laboratory of Physical Chemistry of Solid Surfaces,Department of Chemistry,college of Chemistry and chemical engineering,Xiamen university,Xiamen 361005,China 2 college of Chemistry and chemical engineering,Ocean university of China,Qingdao 266100,China State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China college of Chemistry and chemical engineering Ocean University of China Qingdao China

An array electrode technique was developed as a novel electrochemical method for studying the interaction between macrocell and microcell in the early corrosion process of reinforcing steel in cement *** corrosion potential and galvanic current of macrocell corrosion of the reinforcing steel in cement mortar were imaged by the array electrode technique during the corrosion initiation and *** was certified that the corrosion macrocell current is closely related with the difference of corrosion potential between the anodic and cathodic *** corrosion macrocell and microcell always exist during the corrosion *** interaction of corrosion macrocell and corrosion microcell of steel in concrete was directly sensed by the array electrode for the first time,and was discussed in terms of corrosion electrochemistry.

关键词： reinforcing steel in concrete array electrode macrocell microcell

Cell-SELEX-based aptamer-conjugated nanomaterials for enhanced targeting of cancer cells

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Science China Chemistry 2011年第8期54卷 1218-1226页

作者： KONG RongMei, CHEN Zhuo, YE Mao, ZHANG XiaoBing & TAN WeiHong State Key Laboratory for Chemo/Biosensing and Chemometrics college of Chemistry and chemical engineering, Hunan university, Changsha 410082, China State Key Laboratory for Chemo/Biosensing and Chemometrics college of Chemistry and chemical engineering Hunan University Changsha China

Early detection and treatment of cancer depends on developing highly sensitive and specific methods for targeting cancer cells. To do this, aptamers, which are generated by a novel technique caUed ceU-SELEX （systematic evolution of ligands by exponential enrichment）, have been widely applied in cancer cell targeting based on such merits as high target affinity and specificity, small size, minimal immunogenicity, and ease of chemical modification. Furthermore, aptamers can gain more flexibility as cancer cell targeting tools when conjugated to nanomaterials, including metallic nanoparticles, quantum dots, silica nanoparticles, and carbon nanomaterials, among others. In this review, we discuss the use of cell-SELEX-based aptamer-nanomaterials conjugates as novel molecular tools for enhanced targeting of cancer cells.

关键词： celI-SELEX aptamer nanomaterial cancer cells targeting