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Statistical theory for hydrogen bonding fluid system of A_aD_d type(Ⅲ):Equation of state and fluctuations

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Science china Chemistry 2007年第2期50卷 183-189页

作者： WANG HaiJun1,2,GU Fang1,HONG XiaoZhong3 & BA XinWu1 1 College of Chemistry and Environment Science,Hebei University,Baoding 071002,china 2 international center for materials physics,chinese academy of sciences,shenyang 110016,china 3 College of physics Science and Technology,Hebei University,Baoding 071002,china College of Chemistry and Environment Science Hebei University Baoding China international center for materials physics Chinese Academy of Sciences Shenyang China College of physics Science and Technology Hebei University Baoding China

The equation of the state of the hydrogen bonding fluid system of AaDd type is studied by the principle of statistical mechanics. The influences of hydrogen bonds on the equation of state of the system are obtained based on the change in volume due to hydrogen bonds. Moreover,the number density fluc-tuations of both molecules and hydrogen bonds as well as their spatial correlation property are inves-tigated. Furthermore,an equation describing relation between the number density correlation function of "molecules-hydrogen bonds" and that of molecules and hydrogen bonds is derived. As application,taking the van der Waals hydrogen bonding fluid as an example,we considered the effect of hydrogen bonds on its relevant statistical properties.

关键词： hydrogen bonding fluid equation of state fluctuation correlation effect

Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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Science china Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2, HONG Xiaozhong3, GU Fang1 & BA Xinwu1 1. College of Chemistry and Environment Science, Hebei University, Baoding 071002, china 2. international center for materials physics, chinese academy of sciences, shenyang 110016, china 3. College of physics Science and Technology, Hebei University, Baoding 071002, china 1. College of Chemistry and Environment Science Hebei University Baoding 071002 China 2. international center for materials physics Chinese Academy of Sciences Shenyang 110016 China 3. College of physics Science and Technology Hebei University Baoding 071002 China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

Bulk metallic glasses formed by alloying the Cu_6Zr_5 cluster

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international Journal of Minerals,Metallurgy and materials 2007年第S1期15卷 39-42页

作者： Yanhui Li1), Qing Wang1), Jiang Wu1), Jianbing Qiang1), and Chuang Dong1,2) 1) State Key Lab of materials Modification, Dalian University of Technology, Dalian 116024, china 2) international center of materials physics, chinese academy of sciences, shenyang 110016, china

The bulk metallic glass formation in the Cu-Zr-M ternary systems by alloying of a binary basic Cu6Zr5 cluster was inves- tigated, where M stands for Sn, Mo, Ta, Nb, Ag, Al and Ti. The Cu6Zr5 cluster is a capped Archimedean antiprism that characterizes the local structure of the Cu10Zr7 crystalline phase. This cluster composition almost superposes with Cu-Zr eutectic Cu0.56Zr0.44. A se- ries of alloys along the cluster line (Cu6Zr5)1-xMx were examined for their glass forming abilities. Alloy rods with a diameter of 3 mm were prepared by copper mould suction casting method and analyzed by XRD and thermal analysis. The Cu-Zr based bulk metallic glasses were discovered with minor Nb, Sn, Mo, Ta additions (≤2at%) and Al, Ti, Ag (8at%≤concentration≤9at%). The alloying mechanism was discussed in the light of atomic size, cluster-linking structure and electron concentration factors.

关键词： bulk metallic glasses cluster electron concentration atomic size minor-alloying Cu-Zr alloys

Glass formation of ternary Sm-based Sm-Al-Co bulk metallic glasses

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international Journal of Minerals,Metallurgy and materials 2007年第S1期15卷 50-53页

作者： Jiang Wu1), Qing Wang1), Weirong Chen1), Qingyu Zhang1), Jianbing Qiang1), and Chuang Dong1,2) 1) State Key Lab of materials Modification, Dalian University of Technology, Dalian 116024, china 2) international center of materials physics, chinese academy of sciences, shenyang, 110016, china

Ternary Sm-based Sm-Al-Co alloys at specific compositions designed using an e/a- and cluster-related criteria exhibit high glass forming abilities and form bulk glassy rods of 3 mm in diameter by a copper mold suction-casting method. Four composi- tions of bulk metallic glasses (BMGs) are Sm50Al25Co25, Sm52Al24Co24, Sm54Al23Co23 and Sm56Al22Co22, which all satisfy a constant conduction electron concentration of 1.5. Among them, the BMG exhibiting the largest reduced glass transition temperature (Trg) is Sm50Al25Co25, which reaches 0.648. The glass transition temperature Tg and the onset crystallization temperature Tx of this alloy are respectively 579 and 640 K at a heating rate of 20 K/min.

关键词： Sm-based alloys bulk metallic glasses alloy design cluster line electron concentration

Cluster-based composition rules for ternary alloy systems

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international Journal of Minerals,Metallurgy and materials 2007年第S1期15卷 1-3页

作者： Chuang Dong1, 2), Qing Wang1), Weirong Chen1), Qingyu Zhang1), Jianbing Qiang1), and Yingmin Wang1) 1) State Key Laboratory of materials Modification, Dalian University of Technology, Dalian 116024, china 2) international center for materials physics, chinese academy of sciences, shenyang 110016, china

The cluster-based composition rule in ternary alloy systems including quasicrystals, bulk metallic glasses, crystalline phases and Lave phases-related body-centered cubic (BCC) solid solution forming systems was summarized. The so-called cluster line in a ternary phase diagram refers to a straight composition line linking a specific binary cluster to the third element. The compo- sition ranges of quasicrystals and bulk metallic glasses can be determined by the direct use of cluster lines, where two cluster lines intersect at the optimum phase forming composition. Furthermore, the alloys on the cluster line in Laves phase-related BCC solid solution alloy systems have larger hydrogen storage capacities.

关键词： cluster line composition design quasicrystals bulk metallic glasses hydrogen storage alloys

准二维电荷密度波导体钾紫青铜K_xMo_6O_(17)单晶样品的制备

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物理学报 2004年第3期53卷 895-899页

作者：王俊峰熊锐余恒李慧汤五丰余祖新石兢田德诚田明亮张裕恒武汉大学物理科学与技术学院武汉430072 中国科学技术大学结构分析中心合肥230026

采用碳酸盐替代高钼酸盐电解还原的方法成功制备出了准二维电荷密度波导体钾紫青铜单晶 .通过x射线衍射、透射电子显微术等方法对单晶进行结构分析表明 :晶胞参数a =b =0 5 5 4 0nm ,c =1 35 0 8nm ,单晶为三角晶系 ,对称群为P3- .电... 详细信息

采用碳酸盐替代高钼酸盐电解还原的方法成功制备出了准二维电荷密度波导体钾紫青铜单晶 .通过x射线衍射、透射电子显微术等方法对单晶进行结构分析表明 :晶胞参数a =b =0 5 5 4 0nm ,c =1 35 0 8nm ,单晶为三角晶系 ,对称群为P3- .电阻温度关系曲线的测量显示 :钾紫青铜KxMo6 O1 7单晶在

关键词：钾紫青铜电荷密度波 Peierls相变钼酸钾单晶 X射线衍射结构分析晶胞参数

粘结超磁致伸缩Tb-Dy-Fe合金磁致伸缩性能的研究

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中国稀土学报 2003年第6期21卷 729-732页

作者：王博文李淑英闫荣格曹淑英翁玲河北工业大学磁技术与磁材料研究中心天津工业大学理学院天津300160

采用粘结方法制备了Tb1-xDyxFe2棒状合金样品,经筛选确定了粘结材料的制备工艺,测试了粘结棒状合金样品的静态、动态磁致伸缩系数和磁机械耦合系数k33。结果表明,所制备的粘结棒状样品具有较高的磁致伸缩性能,且动态磁致伸缩参数d33和... 详细信息

采用粘结方法制备了Tb1-xDyxFe2棒状合金样品,经筛选确定了粘结材料的制备工艺,测试了粘结棒状合金样品的静态、动态磁致伸缩系数和磁机械耦合系数k33。结果表明,所制备的粘结棒状样品具有较高的磁致伸缩性能,且动态磁致伸缩参数d33和磁机械耦合系数k33高于国外所报道的结果。

关键词：金属材料磁性材料磁致伸缩性能粘结 Terfenol-D 稀土元素 Tb-Dy-Fe合金粘结磁体制备工艺

Unusual Behaviour of Dislocation Velocity Exponent in Dislocation Multiplication Model

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Journal of materials Science & Technology 1998年第3期14卷 215-218页

作者： Xaowei WANG(international Centre for materials physics, Institute of Metal Research, chinese academy of sciences,shenyang 110015, china) international Centre for materials physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The chaotic behaviour of dislocation multiplication process was investigated. The change of Lyapunov exponent which is used to determine the stability of quasi-periodic and chaotic behavior as well as that of equilibrium points, and periodic solution was reported by using an iteration model of dislocation multiplication. An unusual behavior of Lyapunov exponent and Feigenbaum exponent which respond to the geometric convergence of orbit from bifurcation to chaos was shown by dislocation velocity exponent m and there is a distinction on the tendency of convergence for the dislocation multiplication model when it was compared with logistic map. It is reasonable for the difference to be analyzed from the materials viewpoint. (Edited author abstract) 9 Refs.

关键词： Unusual Behaviour of Dislocation Velocity Exponent in Dislocation Multiplication Model

Multirange Fractals in materials: Applications to Fracture and Mechanical Alloying under Ball Milling

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Journal of materials Science & Technology 1997年第4期13卷 255-259页

作者： Chiwei LUNG(international Centre for materials physics, Institute of Metal Research,chinese academy of sciences, shenyang 110015, china) international Centre for materials physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

A new model of multirange fractals is proposed to explain the experimental results observed on the fractal dimensions of the fractured surfaces in materials. A new explanation to the Williford's multifractal curve on the relationship of fractal dimension with fracture properties in materials has been given. It shows the importance of fractorizing out the effect of fractal structure from other physical causes and separating the appropriate range of scale from multirange fractals. Mechanical alloying process under ball milling as a non-equilibrium dynamical system has been also analyzed.

关键词： Ball Applications to Fracture and Mechanical Alloying under Ball Milling Multirange Fractals in materials