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The Characteristic of Electrochemical Oxidation of Aniline on SnO_2.Ti Electrode

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wuhan university Journal of Natural {2. 2001年第4期6卷 836-840页

作者： Wang Yu ling, Cai Nai cai , Huo Yao dong, Chen Hao college of chemistry and Molecular Science, {2. university, {2. 430072. china college of chemistry and Molecular Science Wuhan University Wuhan China

The characteristic of electrochemical oxidation of aniline on SnO 2.Ti electrode is studied. The results indicate that SnO 2.Ti electrode doped F plays a wonderful role in the oxidation of aniline comparing with Pt electrode. The kinetics factors that influence the oxidation rate of aniline on the SnO 2.Ti electrode are determined by the dissolving of the film on the electrode. The dissolving of the film consisted of intermediate products on the electrode is the slow step. The effects of aniline concentration, pH in aniline solution and the current density( i )on the rate of aniline oxidation, the complexity of intermediate products and the basic category of the intermediate products consisted of the film are introduced.

关键词： electrochemical oxidation SnO 2.Ti aniline

A METHOD OF PREPARING SPHERICAL NANO-CRYSTAL CELLULOSE WITH MIXED CRYSTALLINE FORMS OF CELLULOSE Ⅰ AND Ⅱ

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Chinese Journal of Polymer Science 2001年第3期19卷 291-296页

作者： Xiao-fang Li En-yong Ding Guo-kang Li Laboratory of Cellulose and Lignocellulosics chemistry, Guangzhou Institute of chemistry, Chinese Academy of {2., Guangzhou 510650 china college of Material Science and Engineering south china university of Technology, Guangzhou 510641, china 中科院广州化学所广东广州

A new kind of nano-crysta cellulose (NCC) prepared from natural cotton fiber has been obtained by the method ofacid hydrolysis. Compared to most other nanophase materials that derive from inorganic materials, our products are preparedfrom natural cotton fibers. The products are of spherical shape with mixed crystal forms of cellulose I and II. The preparationconditions determine the properties of the products. Prior treatment is a critical procedure. The properties of the products arealso strongly affected by such conditions as the kinds of acids used, the ratio of the acid mixture, the acid concentration, theultrasonic agitation time and hydrolysis temperature. The number average molecular weight of NCC is determined by gelpermeation chromatography (GPC). The particle size and shape were determined by transmission electron microscopy(TEM). X-ray diffraction was used to detect the crystallinity and average crystallite size of the panicle.

关键词： Spherical nano-crystal cellulose Mixed crystal forms of cellulose Ⅰ and Ⅱ, Ultrasonic agitation

A new method to improve surface morphology of Ni-Fe-Mo-Co alloy electrode and its catalytic activity for HER

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Rare Metals 2007年第3期26卷 205-212页

作者： LUO Beiping REN Buye XU You ZHENG Yajie Department of chemistry and Chemical Engineering Hunan Institute of Science and Technology Yueyang 414000 China college of Metallurgical Science and Engineering Central South University Changsha 410083 China Research Institute of Materials Science South China University of Technology Guangzhou 510640 China

A new pretreatment method has been developed to improve the catalytic activity of the Ni-Fe-Mo-Co alloy electrode for hydrogen evolution reaction （HER）. The procedure involves pre-electrolyzing the Ni-Fe-Mo-Co alloy electrode in 30% KOH solution containing 10% potassium sodium tartrate at 70℃ for 2.h, until some of the Mo and Fe elements are leached out. The surface morphology of the Ni-Fe-Mo-Co alloy demonstrates a unique hive-like structure after the pre- treatment, which has the pore size in a nanometer range （about 50 nm）, a very large real surface area, and good stability. The results of the electrochemical studies show that compared to other similar electrode materials and the treated Ni-Fe-Mo-Co electrode by leaching method, the pre-treated Ni-Fe-Mo-Co electrode has a much lower overpotential and much higher exchange current density for HER. In addition, a long-term continuous electrolysis test with a current interruption shows that the Ni-Fe-Mo-Co alloy has excellent catalytic stability.

关键词： catalytic activity surface treatment Ni-Fe-Mo-Co alloy hydrogen evolution electrodeposition

Enrichment of Trace Scandium with Microcrystalline Naphthalene and Subsequent ICP-AES Determination

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wuhan university Journal of Natural {2. 1998年第2期3卷 205-208页

作者： Xiong Hongchun, Liao Zhenhuan, Peng Tianyou, Deng Zhonghua, Jiang Zucheng(college of chemistry, {2. university, {2. 430072.china) wuhan university College of Chemistry Wuhan China (GRID:grid.49470.3e) (ISNI:***)

A new method is proposed to preconcentrate and separate trace scandium from a large volume of aqueous solution by solid liquid extraction with microcrystalline naphthalene. Scandium oxinate can be adsorbed onto microcrystalline naphthalene quantitatively under certain conditions. The effects of various experimental parameters have been optimized. The influence of additive of cobalt (II) on recovery of scandium (III) is studied in detail. The proposed method has been used for determination of Sc in Certified Reference Material of “Vehicle Exhaust Particulates”.

关键词： Key words scandium cobalt microcrystalline naphthalene inductively coupled plasma atomic emission spectrometry (ICP AES) solid liquid extraction

Size-dependent hydroxyl radicals generation induced by SiO_2.ultra-fine particles: The role of surface iron

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Science china chemistry 2009年第7期52卷 1033-1041页

作者： SHANG Yu1, ZHU Tong1, LI Yi1,2.& ZHAO JinCai3 1 college of Environmental sciences and Engineering, Peking {2., Beijing 100871, china 2.Chinese Academy of Meteorological sciences, Beijing 100871, china 3 Institute of chemistry, Chinese Academy of sciences, Beijing 100871, china college of Environmental sciences and Engineering Peking University Beijing China Chinese Academy of Meteorological sciences Beijing China Institute of chemistry Chinese Academy of Sciences Beijing China

Oxidative stress and hydroxyl radicals (·OH) play important roles in adverse health effects caused by inhalable ambient air particles (PM10). The ultra-fine fraction of PM10 has been hypothesized as one of the critical contributors to ·OH generation. Both in vivo and in vitro studies have shown that ultra-fine particles (UFPs) or nano-particles generate more ·OH than larger particles with identical mass and composition. Both the surface area and surface-adsorbed redox-active metals have been suggested as factors to determine the oxidative capacity of UFPs. In this study, the ·OH-generating capability of dif-ferent sizes of SiO2.particles was investigated in order to determine which factor influences particle-induced ·OH generation. The amount of ·OH generated in both acellular and cellular systems was quantified using a capillary electrophoresis method following exposure to SiO2.particles with diameters of 14, 100, and 500 nm. The amount of ·OH was strongly dependent on particle size, and a significant enhancement was observed only with 14 nm particles. Further studies indicated a close association between ·OH and iron ion concentration (R2.= 0.812. p2.particles is presented as a possible mechanism of UPFs-induced ·OH generation. The SiO2.acted as an inert substrate, and the surface of ultra-fine SiO2.particles acted as a carrier for iron.

关键词： ultra-fine particles nano-particles ·OH oxidative stress size-effect

An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3 1 Technical Institute of Physics and chemistry,Chinese Academy of sciences,Beijing 100080,{2. 2.college of chemistry and Chemical Engineering,Graduate university of Chinese Academy of sciences,Beijing 100049,{2. 3 School of Chemical Engineering and Environment,Beijing Institute of Technology,Beijing 100081,{2. Technical Institute of Physics and chemistry Chinese Academy of Sciences Beijing China college of chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing China School of Chemical Engineering and Environment Beijing Institute of Technology Beijing China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Hydroisomerization of n-heptane over bimetal-bearing H_3PW_(12.O_(40) catalysts supported on dealuminated USY zeolite

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Science china chemistry 2008年第2期51卷 120-127页

作者： WEI RuiPing1,2. GU YanBo1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented Chemical Engineering, college of chemistry and Chemical Engineering, Nanjing Uni- versity of Technology, Nanjing 2.0009,{2. 2.college of chemistry and Chemical Engineering, southeast university, Nanjing 2.1189,{2. State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemistry and Chemical EngineeringNanjing University of TechnologyNanjing 210009China college of chemistry and Chemical Engineering Southeast UniversityNanjing 211189China

The bimetal-bearing (CePt or LaPt) 12.tungstophosphoric acid (H3PW12.40 (PW)) catalysts supported on dealuminated USY zeolite (DUSY) were prepared by impregnation and characterized by XRD, BET, IR, and H2.chemisorption. Their catalytic activities were tested in the hydroisomerization of n-heptane with a continuous atmospheric fixed-bed reactor. After the steam treatment combined with the acid leaching, as well as the supporting with PW and the bimetals, the DUSY support retains the Y zeolite porosity and the PW well keeps its Keggin structure in catalysts. The doping of Ce into the catalysts enhances the dispersion of Pt on the catalyst surface. The Pt-bearing PW catalysts doped with Ce or La, especially Ce, exhibit much higher catalytic activity and selectivity than the catalysts without dopants at lowered reaction temperatures. At the optimal reaction conditions, i.e., the reaction temperature of 2.0℃ and WHSV of 1.4 h1, the catalyst with a Pt loading of 0.4%, PW loading of 10% and a molar ratio of Ce to Pt of 15:1 shows a conversion of n-heptane of 70.3% with a high selectivity for isomerization products of 94.1%.

关键词： hydroisomerization of n-heptane bimetal catalyst heteropoly acid USY platinum

Effects of combined substitution of Dy and Mo or Si on the crystal structures and magnetic properties of Nd_(1-y)Dy_yFe_(11-x)TiM_x(M=Mo,Si) compounds

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Science china chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin college of chemistry and Chemical Engineering,Graduate {2. of Chinese Academy of sciences,Beijing 100049,china college of chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12.type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

Studies on the Behaviors of PbSO_4/Pb and PbO_2.PbSO_4 Electrodes Prepared from Lead Carbonate by Powder Microelectrode Technique

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wuhan university Journal of Natural {2. 2000年第4期5卷 474-478页

作者： Dai Zhong-xu, Wang Di-hua, Zou Jin-yun, Zhou Yun-hong college of chemistry and Environmental Science, {2. university, {2. 430072. china college of chemistry and Environmental Science Wuhan University Wuhan China

The behaviors ot PbSO4/Pb and PbO4/PbSO4 electrode prepared from PbCO3 have been examined using powder microelectrode(PME) technique and cyclic voltammetry(CV). Firstly, PMEs parked with Pb- CO3 transformed into PtSO4 PME in 1. 0 mol/L H2.O4 solution at 30 C, and then the PbSO4 in the PMEs were formed to Pb or PbO2.using an unsymmetrical signal(Qa/Qe for PbSO4/Pb electrode and Qe/Qa for PsO2. PbSO4 electrode being 0. 1-0. 3) in 2. S mol/L H2.O4 solution. The results show that the CV characteristic of either PbSO4/Pb or PsO2.PbSO4 PME prepared from PhCO3 are as good as that of both electrodes made from lead oxide powder produced by ball mill.

关键词： lead carbonate powder microelectrode lead/acid battery formation