检索结果-南通市图书馆

Atomic states and properties of Pt-electrocatalyst

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2006年第3期49卷 291-296页

作者： PENG Hongjian xie youqing College of Chemistry and Chemical Engineering College of Materials Science and Engineering Central South University Changsha 410083 China College of Chemistry and Chemical Engineering College of Materials Science and Engineering Central South University Changsha 410083 China

Using the one-atom theory (OA), the atomic state of Pt-electrocatalyst with fcc structure was determined as follows: [Xe] (5dn)6.48 (5dc)2.02 (6sc)1.48(6sf)0.02. The atomic states of this metal with hcp and bcc structures of primary characteristic crystals and liquid state was also studied. According to its atomic states, the relationship between the atomic states and crystalline structure, catalytic performance and conductivity was explained qualitatively. The potential curve, the temperature dependence of bulk modulus and linear thermal expansion coefficient of fcc-Pt were calculated quantitatively.

关键词： Pt-electrocatalyst, atomic states, crystalline structure, catalytic performance.

Research on atomic states, physical properties and catalytic performance of Ru metal

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2007年第2期50卷 177-183页

作者： PENG HongJian xie youqing LIU ShaoQian College of Chemistry and Chemical Engineering College of Materials Science and EngineeringCentral South UniversityChangsha 410083China

Using the one-atom theory (OA) of pure metals, the atomic states of Ru metal with hcp structure, fcc structure, bcc structure and liquid state were determined as fol- lows: [Kr](4dn)3.78(4dc)2.22(5sc)1.77(5sf)0.23,Ψa(fcc-Ru)=[Kr](4dn)3.70(4dc)2.44 (5sc)1.42(5sf)0.44, Ψ a(bcc-Ru)=[Kr](4dn)4.00(4dc)2.22(5sc)1.56(5sf)0.22, Ψ a(L-Ru)=[Kr](4dn)4.00(4dc)2.00(5sc)1.52 (5sf)0.48. The potential curve and physical properties as a function of temperature for hcp-Ru such as lattice constant, cohesive energy, linear thermal expansion coeffi- cient, specific heat and Gibbs energy and so on were calculated quantitatively. The theoretical results are in excellent agreement with experimental value. The rela- tionship between the atomic states and catalytic performance was explained qualitatively and these supplied the designation of Ru metal and relative materials with theoretical instruction and complete data.

关键词： Ru metal atomic states physical properties catalytic performance

Computation of concentrations of characteristic atoms of alloys in BCC structure

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第9期54卷 2363-2367页

作者： PENG HongJian WU Qing LI XiaoBo xie youqing School of Chemistry and Chemical Engineering Central South University Changsha 410083 China Schooi of Material Science and Engineering. Central South University Changsha 410083 China

In this paper, taking Nb-Mo alloy system as an example, the equations of concentration of characteristic atoms of alloys in BCC structure were obtained on the basis of the idea of systematic science of alloys and the number of coordination atoms. The concentrations of characteristic atoms in B2-NbMo type ordered alloys were calculated as functions of ordering degree（s） and composition Xuo. When S=Smax, the concentrations of characteristic atoms of stoichiometric B2-NbMo intermetallic compound are equal to that of alloys, that is, X8^Nb = 0.5 at, X0^Mo= 0.5 at. As ordering degree decreases, characteristic atoms A8^Nb and A0^Mo of B2-NbMo type ordered alloy split. And the degree of splitting of characteristic atoms increases with the ordering degree decreasing. Therefore, disordered alloys and various types of ordered alloys can be designed.

关键词： Nb-Mo alloy system BCC structure concentrations of characteristic atoms

ELECTRONIC STRUCTURE AND PROPERTIES OF Au METAL

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 1992年第2期2卷 56-61页

作者： xie youqing Zhang Xiaodong Ma Xiulin Zhao Liying Central South University of Technology Changsha 410083China

Using the new developed valence bond theory of metals,the electronic structure,crystal structure and physical properties of Au metal have been systematically *** has been determined that its electronic structure is(5d_(n))^(4.65)(5d_(c))^(4.71)(6s_(c))^(0.62)(6s_(f))^(1.02).According to this electronic structure,lattice constant,cohesive *** curve,bulk modulus and temperature dependence of liner thermal expansion coeCHcient have been *** theoretical values of properties are all in good agreement with experimental *** electronic structure has been verified in part by linear rigorous cellular method of band *** shows that the valence bond theory has been reached perfectly.

关键词： Au electronic structure potential Ainction lattice constant cohesive energy thermal expansion coefficient

Low temperature thermodynamic study of the stable and metastable phases of vanadium

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2007年第22期52卷 3041-3046页

作者： LI XiaoBo xie youqing NIE YaoZhuang PENG HongJian College of Materials Science and Engineering Central South University Changsha 410083 China

The low temperature thermodynamics of the stable phase of vanadium has been assessed by the polynomial and Debye models from the experimental data available in literature. By means of the con-strained nonlinear least squares curve fitting arithmetic,two sets of parameter values have been de-termined. Expressions of the thermodynamic functions Cp(T) and G(T)-H(298.15 K) at 0―298.15 K are presented. The low temperature thermodynamics of the metastable phase of vanadium can only be extrapolated by the Debye model. The expression of the thermodynamic function Cp(T) at 0―298.15 K is presented.

关键词：温度热力学钒稳定状态

Electronic structures and properties of pure vanadium

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 1999年第3期9卷 446-450页

作者： He Yu(贺昱) xie youqing(谢佑卿) Peng Kun(彭坤) Liu Xinbi(刘心笔) Cent S Univ Technol Dept Mat Sci & Engn Changsha 41083 Peoples R China

By the one atom theory the electronic structure of bcc V has been determined to be [Ar](3d n) 1.799 8 (3d c) 2.657 8 (4S c) 0.171 1 (4s f) 0.371 3 . According to this electronic structure of bcc V, its potential curve, cohesive energy, lattice parameter, elasticity and linear thermal expansion coefficient were calculated. The electronic structures of the primary state crystals of fcc V, hcp V and the primary state liquid—V have also been studied.

关键词： vanadium electronic structure physical properties

Research on properties of DO_3- and B2-type ordered alloys and disordered alloys in Nb-Mo alloy system in BCC structure

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第12期54卷 2808-2814页

作者： PENG HongJian ZHOU JiaoLian LI XiaoBo xie youqing School of Chemistry and Chemical Engineering Central South University Changsha 410083 China School of Material Science and Engineering Central South University Changsha 410083 China

Based on the idea of systematic science of alloys, we derived the interaction equations of binary alloys in BCC structure in this paper. According to the basic information of characteristic atoms sequences and characteristic crystals sequences of Nb-Mo alloy system and the concentrations of characteristic atoms of Nb-Mo alloy system, the properties of DO3-Nb3Mo type ordered alloys, B2-NbMo type ordered alloys and DO3-NbMo3 type ordered alloys and disordered alloys were calcu-lated. The results show that the properties of ordered alloys exhibit stronger variations than those of disordered Nb(1-x)Mox alloys when approaching the stoichiometric ratio, whereas the opposite trend occurs when deviating from the stoichiometric ratio. The main reason is that the ordering degree is maximal at the stoichiometric ratio while it decreases linearly when deviating from stoichiometric ratio. On the contrary, the number of bonding electrons among atoms increases with the simultaneous decreasing of the nearly free electrons, which shortens the bond lengths and thus strengthens the crystal bonding.

关键词： Nb-Mo alloy system ordered and disordered alloys properties

同方期刊数据库

RELATIONSHIP OF LENNARD－JONES POTENTIAL ANDMORSE POTENTIAL WITH W＿x（r） POTENTIAL

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 1994年第3期4卷 63-66页

作者： xie , youqing(Departement of Materials Science and Engineeing ,Central South University of Technology ,Changsha 410083)

ＲＥＬＡＴＩＯＮＳＨＩＰＯＦＬＥＮＮＡＲＤ－ＪＯＮＥＳＰＯＴＥＮＴＩＡＬＡＮＤＭＯＲＳＥＰＯＴＥＮＴＩＡＬＷＩＴＨＷ＿ｘ（ｒ）ＰＯＴＥＮＴＩＡＬＸｉｅ，Ｙｏｕｑｉｎｇ（ＤｅｐａｒｔｅｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃ... 详细信息

ＲＥＬＡＴＩＯＮＳＨＩＰＯＦＬＥＮＮＡＲＤ－ＪＯＮＥＳＰＯＴＥＮＴＩＡＬＡＮＤＭＯＲＳＥＰＯＴＥＮＴＩＡＬＷＩＴＨＷ＿ｘ（ｒ）ＰＯＴＥＮＴＩＡＬＸｉｅ，Ｙｏｕｑｉｎｇ（ＤｅｐａｒｔｅｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｉｎ...

关键词： potential function cohesive energy thermal expansion elastic modulus

在线全文

学校读者我要写书评

暂无评论

确定二元合金系特征原子序列的方法

金属学报 2008年第6期44卷 764-768页

作者：彭红建谢佑卿中南大学化学化工学院长沙410083 中南大学材料科学与工程学院长沙410083

以Pt-Ru合金系为例,指出了确定二元合金系特征原子序列的方法,根据无序合金的品格常数和生成热的实验值,选择合适的方程作为其能量和体积的相互作用方程,然后即可确定合金系特征原子序列的基本信息,便可阐明并设计无序、有序合金的结构... 详细信息

以Pt-Ru合金系为例,指出了确定二元合金系特征原子序列的方法,根据无序合金的品格常数和生成热的实验值,选择合适的方程作为其能量和体积的相互作用方程,然后即可确定合金系特征原子序列的基本信息,便可阐明并设计无序、有序合金的结构和性质,对于Pt-Ru合金系,能实现电子结构和催化性能的关联,随配位Ru原子的增加,合金势能降低,稳定性增强,d空穴增加,品格常数减小,催化活性增强。

关键词： Pt—Ru合金系特征原子序列催化活性