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Science china chemistry 2005年第z1期48卷 9-13页

作者： HE Shuiyang,PENG Ke,NING Wei,WANG Daqi & SHI Qizhen Department of chemistry,Northwest university and Shaanxi Key Laboratory of Physico-Inorganic chemistry,Xi’an 710069,china college of chemistry and chemical engineering,liaocheng university,liaocheng 2.2.59,china 1. Department of chemistry Northwest University and Shaanxi Key Laboratory of Physico-Inorganic Chemistry 710069 Xi’an China 2. college of chemistry and {2. engineering Liaocheng University 252059 Liaocheng China

A novel compound (NH4)2.(H2.)8[PMo10V2.40]·10H2. has been prepared in an aqueous solution and characterized by elemental analysis, IR, and TG-DTG analysis. X-ray diffraction analysis was carried out on (NH4)2.(H2.)8 [PMo10V2.40]·10H2. single crystal, which crystallizes in the monoclinic system of a space group P2./C with a=0.9871(3) nm,b=1.542.(5) nm,c=2.792.(9) nm,β=94.183(5)°and Z=2. In the compound, a two-dimensional network is constructed by the PMo10V2.405- anion and the Y(H2.)83+ cation building blocks via hydrogen bonding exhibiting the porous structure.

关键词： crystal structure, polyoxoanion, yttrium, supramolecular network.

Fabrication of the DNA/poly(3-methylthiophene) composite film modified electrode and its application for the study on the voltammetric behavior and determination of 8-hydroxy-2.-deoxyguanosine

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Science china chemistry 2009年第11期52卷 2006-2012页

作者： WANG YanHuai,LI Jing,LIU Yan,MA RongNa,JIA WenLi,CUI Hui & WANG HuaiSheng college of chemistry and {2. engineering,Institute of Analytical chemistry,liaocheng university,liaocheng 2.2.59,china 1. college of chemistry and {2. engineering Institute of Analytical Chemistry Liaocheng University Liaocheng 252059 China

A composite film of DNA/poly(3-methylthiophene)(P3MT) modified glassy carbon electrode(GCE) has been fabricated by electro-deposition method.P3MT film was first electropolymerized at the GCE and the DNA layer was then immobilized on the P3MT layer by electrochemical *** voltammetric behavior of 8-hydroxy-2.-deoxyguanosine(8-OH-dG) at the composite film modified electrode was *** effects of scan rates,pH and the interference of uric acid(UA) on the voltammetric behavior and detection of 8-OH-dG were also *** experimental results suggest that the electrochemical behavior of 8-OH-dG at the composite film modified electrode was greatly improved due to the combination of the advantages of P3MT and *** 0.1 M pH 7.0 phosphate buffer solution(PBS),the anodic peak currents of 8-OH-dG were linear with the 8-OH-dG concentration in two intervals,viz.0.2.―4.2.μM and 4.2.19.6 μ*** detection limit of 56 nM 8-OH-dG could be estimated(S/N=3).This proposed composite film modified electrode shows excellent reproducibility and *** may have the potential application for the detection of 8-OH-dG in human urine.

关键词： poly(3-methylthiophene) DNA 8-hydroxy-2.-deoxyguanosine composite film modified electrode

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 {2. engineering, Central South university, Changsha 410083, china 2. college of chemistry and {2. engineering, Yueyang Normal university 1. college of chemistry and {2. engineering Central South University 410083 Changsha China 2. college of chemistry and {2. engineering Yueyang Normal University 414000 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 392., the column efficiencies are respectively 3084 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 8.2. and 1.019.

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

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 {2.ing, Qingdao university of Science and Technology, Qingdao 2.6042. china 2. college of chemistry and chemical {2.ing, Ocean university of china, Qingdao 2.6003, china Correspondence should be addressed to Jiao Kui 1. college of chemistry and Molecular {2.ing Qingdao University of Science and Technology 266042 Qingdao China 2. college of chemistry and {2. engineering Ocean University of China 266003 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

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 2.5006, 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 1. Department of chemistry College of Chemistry and Chemical Engineering Suzhou University 215006 Suzhou China 2. State Key Laboratory for Physical chemistry of Solid Surfaces and Department of chemistry College of Chemistry and Chemical Engineering Xiamen University 361005 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.

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, {2. of chemistry and chemical engineering, Nanjing Uni- versity of Technology, Nanjing 2.0009, china 2.{2. of chemistry and chemical engineering, Southeast university, Nanjing 2.1189, china State Key Laboratory of Materials-Oriented chemical engineering College of Chemistry and Chemical EngineeringNanjing University of TechnologyNanjing 210009China college of chemistry and {2. 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

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. ZHANG Jiao qiang 3 (1. Department of chemistry,Northwest university, Xi′an 710065,{2. 2. Department of chemistry and chemical engineering, Baoji college of Arts and Science, Baoji 72.007,{2. 3. Department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Theoretical Study on Dehydrogenation Reactions of Silanol

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chemical Research in Chinese Universities 1990年第3期6卷 188-193页

作者： Han Yunzhu (Department of chemistry, liaocheng Teachers {2., liaocheng)Zhao Chengda (Department of chemistry, Northeast Normal university, Changchun)

The pathway of dehydrogenation reaction of silanol SiH3OH is investigated by ab initio Mo calculations using RHF/-31G basis set. The geometries of reactant, transition states and products are optimized on the singlet potential energy surface of the ground state. The activation energies, reaction heats, statistical A factor and activation entropies are calculated. The vibrational analysis of the reactant and the transition states is made. The reaction crgodography along the intrinsic reaction coordinate (IRC) are performed to examine the reaction mechanism.

关键词： Silanol Intrinsic reaction coordinate Ab initio Dehydrogenation

Synthesis and Crystal Structure of One-dimensional Chain Complexes [K（18-C-6）]2.M（mnt）2.（M=Zn,Hg）

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chemical Research in Chinese Universities 2003年第3期 263-268页

作者： WANG Da qi 1, HE Guo fang 2. QIU Lin lin 2.and DOU Jian min 1,* 1. Department of chemistry, liaocheng university, {2. 2.2.00, P. R. china 2. Department of chemistry, Taishan college, Taian 2.102., P. R. china

The reactions of 18 crown 6 with each of K 2.M=Zn, Hg; mnt=1,2. dicyanoethene 1,2. dithiolate, C 2. 2.CN) 2. 2. were studied and novel complexes [K(18 C 6)] 2.Zn(mnt) 2.(1) and [K(18 C 6)] 2.Hg(mnt) 2.(2. were characterized by elemental analysis, IR spectrum and X ray diffraction analysis. Complex 1 displays a one dimensional chain of [K(18 C 6)] 2.Zn(mnt) 2. bridged by K O interactions between adjacent [K(18 C 6)] + units. Complex 2.is also a one dimensional chain of [K(18 C 6)] 2.Hg(mnt) 2. bridged by K...S weak interactions between adjacent [K(18 C 6)] + and [Hg(mnt) 2. 2. .

关键词： One dimensional chain Crown ether mnt complex 18 Crown 6 Crystal structure

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 Wuhan university of Technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) Wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

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