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Chinese Chemical Letters 1998年第6期9卷 583-586页

作者： Xin LU Xin XU Nan Qin WANG and Qian Er ZHANG(State Key Laboratory for physical chemistry of Solid Surfaces, Institute of physical chemistry,department of chemistry, Xiamen University, Xiamen 361005) State Key Lab. Phys. Chem. Solid S. Institute of Physical Chemistry Xiamen University Xiamen 361005 China

Ab initio calculations based on density functional theory have been used to study thedecompsition of N_2O on MgO. The reaction is predicted to occur on O_3c and O_(4c) atoms, but not onO_(5c) atoms, with an activation barrier of 25-27 kcal/mol, in agreement with the experimental valueof 35 kcal/mol. Natural bond orbital analysis shows that the reaction leaves O ad-atoms on thosesurface O anions to form a peroxide-like 'O^2_(2-)' species. The )O-O bond stretching frequency ispredicted to be in the range from 820 cm(-1) to 825 cm(-1).

关键词： Ab initio calculation N_2O decomposition MgO catalyst

Hydroxyapatite/Metal Composite Coatings Prepared by Two-step Electrodeposition Method

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Chinese Chemical Letters 1998年第4期9卷 403-406页

作者： Jian Min ZHANG Chang Jian LIN Zu De FENG Zhao Wu TIAN(State Key Lab. for physical chemistry of Solid Surface, Institute of physical chemistry, department of chemistry, department of Materials Science, Xiamen University, Xiamen 361005) State Key Lab. Phys. Chem. Solid S. Institute of Physical Chemistry Xiamen University Xiamen 361005 China

A two-step electrodeposition method was developed to prepare hydroxyapatite/metal composite coatings. Hydroxyapatite coatings were fabricated by electrochemical deposition and post-treatment with alkaline solution, and then cobalt was electrodeposited to form hydroxyapatite/cobalt composite coatings to improve its mechanical properties of bonding strength.

关键词： hydroxyapatite electrodeposition composite coating

COMPUTER OPTIMIZATION OF DENSITY AND VISCOSITY FOR BINARY METALLIC MELTS

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中国有色金属学会会刊：英文版 1995年第2期5卷 30-33页

作者： Zhang,Jiayun Zhou, Tuping Feng, Xueliang (department of physical chemistry,University of Science and Technology Beijing, Beijing 100083) Univ of Science and Technology Beijing Beijing China

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关键词： metallic melts viscosity computer optimization

XRD & XPS Study on the BaF_2 Promoted Sm_2O_3-LaF_3 Catalysts

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Chinese Chemical Letters 1997年第1期8卷 83-86页

作者： Ji Zhong LUO and Hui Lin WAN(department of chemistry & State Key Laboratory for physical chemistry of the Solid Surface, Xiamen UniversityXiamen 361005) department of chemistry State Key Lab. Phys. Chem. Solid S. Xiamen University Xiamen 361005 China

Sm2O3-LaF3 and BaF2 promoted Sm2O3W3 catalysts shown good catalytic performance for the Oxidative Dehydrogenation of Ethane(ODE). XRD and XPS characterizations of the catalysts show the structure defects, which may be produced by the partial exchange of anions and cations,enhance the electron donating ability and increase the surface absorbed oxygen concentration thus should be favorable to improve the catalytic activity. However, the higher concentration of surface adsorbed oxygen is unfavorable for the ethene selectivity.

关键词： Sm La XRD XPS Study on the BaF2 Promoted Sm2O3-LaF3 Catalysts

Preparation and Characterization of Gold Thin Film Electrode Modified by Microbe

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Chinese Chemical Letters 1999年第4期10卷 311-312页

作者： Jin Kun FU Rong Zong HU Wei De ZHANG Xin Sheng YU Jin Yin FU(State Key Laboratory for physical chemistry of Solid Surface, department of chemistry and Institute of physical chemistry, Xiamen University, Xiamen 361005) State Key Lab. Phys. Chem. Solid S. Department of Chemistry Xiamen University Xiamen 361005 China

A novel method based on microbe modification has been employed to prepare gold thin film electrode. The preparation method is simple and the electrode obtained is stable and very sensitive in determining heavy metal i... 详细信息

关键词： gold thin film electrode microbe modification trace analysis

Surface activity coefficients of ideal mixtures adsorbed on two-site heterogeneous surface model

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Chinese Journal of chemistry 1987年第1期5卷 22-29页

作者： GU Ti-Ren (Tiren Gu) department of chemistry and Institute of physical chemistry, Peking University, Beijing department of chemistry and Institute of physical chemistry Peking University Beijing

The surface activity coefficients of ideal mixtures adsorbed on the heterogeneous surfaceshave been calculated systematically by using the two-site heterogeneous surface model. The calculatedrcsults show that the apparent surface activity coefficients are alwnys smaller than 1, i.e., negativedeviation from Raoult’s law, which were always found experimentally. On the other hand, the calculatedsurface activity coefficients curves are always nearly symmetric if the total surface coverage is closeto 1. This situation is comparable wth those ofadsorption from solutions. Therefore, the asymmetriccurves for the surface activity coefficients may not be due to the heterogeneous of the surface, butdue to the nonideal molecular interactions between the unlike components of the adsorbed mixture.

关键词： Surface activity coefficients of ideal mixtures adsorbed on two-site heterogeneous surface model

Surface Tension Calculation of Undercooled Alloys

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Rare Metals 2001年第1期20卷 58-61页

作者： Zhiyu Qiao, Lijun Yan, Zhanmin Cao, Guirong Liu (department of physical chemistry, University of Science and Technology Beijing, Beijing 100083, China) 北京科技大学北京 100083

Based on the Butler equation and extrapolated thermodynamic data of undercooled alloys from those of liquid stable alloys, a method for surface tension calculation of undercooled alloys is proposed. The surface tensions of liquid stable and undercooled Ni-Cu (x(Ni)=0.42) and Ni-Fe (x(Ni)=0.3 and 0.7) alloys are calculated using STCBE (Surface Tension Calculation based on Butler Equation) program. The agreement between calculated values and experimental data is good enough, and the temperature dependence of the surface tension can be reasonable down to 150-200 K under the liquid temperature of the alloys.

关键词： undercooled alloy surface tension Butler equation

Wetting and adsorption II. Adsorption of Triton X-100 and Triton X-305 onto carbon black from water and cyclohexane solutions

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Chinese Journal of chemistry 1987年第2期5卷 112-118页

作者： ZHAO Zhen-Guo GU Ti-Ren*, department of chemistry and Institute of physical chemistry, Peking University, Beijing department of chemistry and Institute of physical chemistry Peking University Beijing

The adsorption isotherms of nonionic surfactants Triton X-100 and Triton X-305 fromwater and cyclohexane on carbon black have been determined at 15 and 30℃. The Langmuir-typeand BET-type isotherms are obtained for adsorption of Triton X-100 and Triton X-305 from waterand cyclohexane respectively. Both the contact angles of water for graphite/water/air and graphite/water/cyclohexane decrease monotonously with increasing surfactant concentration. From theseresults, it is proposed that the adsorption of Triton X-100 and Triton X-305 on carbon black or gra-phite from water is monolayer. For the adsorption from cyclohexane solutions, the ethyleneoxidegroup of the surfactant molecules may be adsorbed onto the polar spot at the surface of carbon black,and the hydrophobic group of adsorbed molecules may direct toward the liquid phase or attaches tothe nonpolar surface region around the polar spot. As the concentration increases, the ethyleneoxide groups of the adsorbed molecules can be aggregated with each other via polar interactions toform hemi-reversed micelle.

关键词： Adsorption of Triton X-100 and Triton X-305 onto carbon black from water and cyclohexane solutions

Novel Ru - K/Carbon Nanotubes Catalyst for Ammonia Synthesis

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Chinese Chemical Letters 2000年第4期11卷 373-374页

作者： Yun CAI Jing Dong LIN Hong Bo CHEN Hong Bin ZHANG Guo Dong LIN Dai Wei LIAO (State Key Lab of physical chemistry on Solid Surfaces. department of chemistry Institute of physical chemistry. Xiamen University, Xiamen 361005) State Key Lab Phys. Chem. Solid S. Department of Chemistry Xiamen University Xiamen 361005 China

A novel ammonia synthesis catalyst, potassium-promoted ruthenium supported on carbon nanotubes, was developed. It was found that the Ru-K/carbon nanotubes catalyst had higher activity for ammonia synthesis (20.85 ml NH3/h/g-cat) than the Ru-K/fullerenes ( 13.3 ml NH3/h/g-cat) at atmospheric pressure and 623 K. The catalyst had activity even at 473 K, and had the highest activity( 23.46 ml NH3/h/g-cat) at 643 K. It was suggested that the multi-walled structure favored the electron transfer, the hydrogen-storage and the hydrogen-spill which were favorable to ammonia synthesis.

关键词： ammonia synthesis ruthenium carbon nanotubes