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Science china chemistry 2010年第3期53卷 561-567页

作者： WANG YuFeng,SONG ZhanBo,CHEN ChunXia & PENG JinSong Department of chemistry and chemical engineering,college of Science,Northeast Forestry university,Harbin 150040,china Department of chemistry and chemical engineering College of Science Northeast Forestry University Harbin China

Catalytic performance of different cation-exchanged montmorillonite clays has been investigated in the Pictet-Spengler C-C bond forming reaction.H+-Montmorillonite was found to be a very efficient and reusable catalyst for the endo cyclization of β-phenylethylamine derivatives with aldehydes under solvent-free *** addition,an aqueous condensation version for the synthesis of tetrahydro-β-carbolines using the H+-montmorillonite catalyst has been *** these environmentally friendly processes,the use of organic solvents was avoided and the catalyst was recycled with maintenance of high catalytic activity.

关键词： heterogeneous catalysis catalyst recycling mesoporous materials green synthesis

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

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

A new way to synthesize benzoin isopropyl ether on Cu-Fe-hydrotalcite

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Journal of Natural Gas chemistry 2010年第1期19卷 77-80页

作者： Xianmei Xie, Xia An, Kai Yan, Xu Wu, Jianling Song, Zhizhong Wang college of chemistry and chemical engineering, Taiyuan university of Technology, Taiyuan 030024, Shanxi, china college of chemistry and chemical engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China

An efficient synthesis of benzoin isopropyl ether with benzaldehyde and propanol in the presence of heterogeneous recyclable Cu-Fe-hydrotalcite catalyst has been explored. Cu-Fe-hydrotalcite was firstly successfully synthesized over Jahn-Teller effect of Cu^2＋. The catalytic test result showed that Cu-Fe-hydrotalcite could be used as a good catalyst in the synthesis of benzoin isopropyl ether. The highest conversion of ben- zaldehyde was 59.7% and the selectivity of benzoin isopropyl ether was nearly 100%. By this new method, not only was the cyanide poisoning avoided, but also the synthesis of benzoin isopropyl ether could be completed in one step instead of traditional two steps with both condensation and etherification.

关键词： benzoin isopropyl ether benzaldehyde propanol Cu-Fe-hydrotalcite

Synthesis and Crystal Structure of Bis(nitrate)- bis(N,N'-dimethyl-N,N'-dibenzenyl-urea)uranyl(Ⅱ)

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Chinese Journal of Structural chemistry 2003年第5期22卷 521-524页

作者： ZHU Li-Ming LI Bao-Long② CAO Zheng-Bai ZHANG Yong (college of chemistry and chemical engineering, Suzhou university, Suzhou 215006, china) college of chemistry and chemical engineering Suzhou University Suzhou 215006

The new uranyl complex UO2(NO3)2[PhN(CH3)C(O)(CH3)NPh]2 was synthesized and its crystal structure has been determined by single-crystal X-ray diffraction. Crystal data: C30H32N6O10U, triclinic, space group P with a = 7.772(1), b = 9.267(1), c = 12.644(1) ? a = 68.246(8), b = 73.871(9), g = 84.99(1)o, V = 812.4(2) ?, Mr = 874.65, Z = 1, Dc = 1.788 g/cm3, F(000) = 426, m = 5.062 mm-1, the final R = 0.022 and wR = 0.059 for 3571 observed reflections (I > 2s(I)). The central uranyl ion is coordinated by six oxygen atoms, two from the carbonyl groups of N,N-dimethyl-N,N-dibenzenyl-urea molecules and the other four from two nitrate groups.

关键词： substituted urea uranyl complex synthesis crystal structure

THE SENSITIVITY OF RESPONSE SIGNAL OF SPECTROELECTROchemistry(SEC)

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Chinese chemical Letters 1992年第6期3卷 465-466页

作者： Yuan Bao ZHU Qing Ji XIE Lian Hong CHEN Shuang E HE Department of chemistry and chemical engineering, hunan university, changsha 410082.

In this paper, we propose the use of the molar absorbance/ potential ratio to measure quantitatively the sensitivity of response signal of SEC cell and the system under study. A simple equation was developed, and the major factors influencing the sensitivity were also assessed. The results obtained this way were in good agreement with actual cases.

关键词： SEC THE SENSITIVITY OF RESPONSE SIGNAL OF SPECTROELECTROchemistry length

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 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

Fabrication,property characterization and toughening mechanism of HA-ZrO_2(CaO)/316L fibre composite biomaterials

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Science china(Technological Sciences) 2008年第7期51卷 957-967页

作者： ZOU JianPeng1, HE ZeQiang2, ZHOU ZhongCheng1, HUANG BaiYun1, CHEN QiYuan3 & RUAN JianMing1 1 State Key Laboratory for Powder Metallurgy, Central South university, changsha 410083, china 2 Institute of chemistry and chemical engineering, Jishou university, Jishou 416000, china 3 Institute of chemistry and chemical engineering, Central South university, changsha 410083, china State Key Laboratory for Powder Metallurgy Central South University Changsha China Institute of chemistry and chemical engineering Jishou University Jishou China Institute of chemistry and chemical engineering Central South University Changsha China

HA-ZrO2(CaO)/316L fibre composites were successfully fabricated with vacuum sintering method and their properties and toughening mechanism were studied. The results showed that HA-ZrO2(CaO)/316L fibre biocomposite having 20 vol% fibres had optimal comprehensive properties with bending strength, Young's modulus, fracture toughness and relative density equal to 140.1 MPa, 117.8 GPa, 5.81 MPa·m1/2 and 87.1%, respectively. The research also addressed that different volume ratios of the composites led to different metallographic microstructures, and that metallographic morphologies change regularly with volume ratios of the composites. 316L fibres were distributed randomly and evenly in the composites and the integration circumstance of the two phases was very well since there were no obvious flaws or pores in the composites. Two toughening mechanisms including ZrO2 phase transformation toughening mechanism and fibre pulling-out toughening mechanism existed in the compsites with the latter being the main toughening mechanism.

关键词： vacuum sintering fabrication property characterization toughening mechanism biomaterials

Adsorption and corrosion inhibition behavior of imidazole on cobalt electrodes studied by SERS and electrochemical methods

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Science china chemistry 2005年第6期48卷 497-503页

作者： GU Wei1, LIU Guokun2, REN Bin2, WU Deyin2, GU Renao1 & TIAN Zhongqun2 1. Department of chemistry, college of chemistry and chemical engineering, Suzhou university, Suzhou 215006, china 2. State Key Laboratory for Physical chemistry of Solid Surfaces and Department of chemistry, college of chemistry and chemical engineering, Xiamen university, Xiamen 361005, china Department of chemistry College of Chemistry and Chemical Engineering Suzhou University Suzhou China State Key Laboratory for Physical chemistry of Solid Surfaces and Department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China

The interaction of imidazole with Co electrodes in an electrochemical system was studied by surface-enhanced Raman scattering (SERS) and electrochemical methods. The SER spectra of Co in an imidazole solution as a function of the applied potential were analyzed and the assignment of the Raman bands was made. It was found that there were three kinds of sur-face species on the Co surface in different potential regions and they were interchangeable de-pending on the potential. In a relatively negative potential region (?1.2 to ?0.9 V), imidazole was adsorbed on the surface and its orientation might change from a vertical configuration via the N-end of the pyridine ring to a tilted configuration via the C2=N3 double bond. In a more positive potential region (?0.8 to ?0.7 V), the SERS signal from the adsorbed imidazole weakened and finally disappeared, meanwhile the signal from the Co and imidazole complex strengthened gradually. At the open circuit potential (?0.6 V), we detected very strong bands from the Co ox-ides. By comparing the Tafel curves of the Co electrode in the solution without and with imidazole, we found that imidazole has a marked effect on the corrosion inhibition of the Co electrode. This result demonstrates that we may be able to reveal the complicated interaction of surface species with metal surface at the molecular level by combining the SERS and electrochemical methods.

关键词： cobalt, imidazole, inhibition, surface-enhanced Raman spectroscopy, Tafel plot.

A simple solvothermal route towards the morphological control of ZnO and tuning of its optical and photocatalytic properties

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Science china chemistry 2010年第8期53卷 1711-1717页

作者： JIANG YaQi,LI FangFang,SUN Ran,XIE ZhaoXiong & ZHENG LanSun State Key Laboratory for Physical chemistry of Solid Surfaces Department of chemistry,college of chemistry and chemical engineering,Xiamen university,Xiamen 361005,china State Key Laboratory for Physical chemistry of Solid Surfaces Department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China

ZnO nanoparticles with different morphologies were solvothermally synthesized by controlling the alkali (sodium hydroxide) concentration in an isopropanol *** products were characterized by means of powder X-ray diffraction,UV-visible absorption spectra,scanning electron microscopy,transmission electron microscopy,and selected area electron *** morphologies of the formed ZnO nanocrystals were dependent on the concentration of the alkali,and with increases of sodium hydroxide concentration,the ZnO nanocrystals evolved from rod to hexagonal bipyramid,and then to a flower-like *** flower-like nanostructure resulted from the etching of the hexagonal bipyramid by the excess *** photoluminescence and photocatalytic properties of the prepared ZnO were *** difference of green emission among the ZnO nanocrystals indicated that a higher sodium hydroxide concentration led to a higher level of *** size,the surface structure and defects in the ZnO nanocrystals affected its photo-degradation characteristics.

关键词： zinc oxide solvothermal method nanocrystal photoluminescence photocatalysis