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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,{2., 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.

Effects of Positron Diffusion and Its Application in Composite System

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Journal of materials Science & Technology 2000年第3期16卷 311-314页

作者： Jian JIANG, Xinzhang ZHOU and ChiWei LUNG (international center for {2. physics, Institute of Metal Research, chinese academy of sciences, shenyang 110015, China) international center for {2. physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The effects of positron diffusion on the measured S parameter have been investigated by a point-source diffusion model and a δ function method. Firstly, the theoretical analyses of the effects are presented for the samples of a homogeneous semi-infinite medium and a film of definite thickness. Then the results are used to analyze the S parameters in several composite systems and interface models.

关键词： Effects of Positron Diffusion and Its Application in Composite System

Effect of cyclic recovery heat treatment on surface recrystallization of a directionally solidified superalloy

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Progress in Natural Science:materials international 2011年第6期21卷 491-495页

作者： Guang XIE~1,Jian ZHANG~(1,2.,Lang-hong LOU~1 1.Superalloys Division,Institute of Metal Research,chinese academy of {2.,shenyang 110016,China 2.shenyang National Laboratory for materials Science,Institute of Metal Research, chinese academy of sciences,shenyang 110016,China [a] Superalloys Division Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China [b] shenyang National Laboratory for materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Microstructural evolution and micro-hardness of a directionally solidified Ni-base superalloy subjected to shot-peening during cyclic recovery heat treatment was *** was found thatγ' dissolved and dislocation annihilation occurred during heating, while y' re-precipitated when temperature *** to the formation of a stable dislocation network at ylf interface,full recovery and therefore complete elimination of the surface recrystallization are difficult by the present cyclic recovery heat treatment.

关键词： recrystallization superalloy dislocation recovery heat treatment

Dislocation Velocity Exponent and the Strain Rate

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Journal of materials Science & Technology 2001年第3期17卷 363-366页

作者： Hongyan LIU and Xiaowei WANG international center for Material {2., Institute of Metal Research, chinese academy of sciences, shenyang 110016, China E-mail: liu@*** chinese Acad Sci Met Res Inst Int Ctr Mat Phys Shenyang 110016 Peoples R China

The process of dislocation multiplication has been described hv chaos theory, trying to reveal the connection between the microstructures on the mesoscopic scale and the mechanical properties of material on the macroscopic scale. The relationship between the dislocation velocity exponent and the maximum of strain rate is given. The results obtained from logistic equation with exponent and the dislocation multiplication dynamic equation are compared. A scale law in one-dimension-map model with exponent is shown when the exponents of equations are changed.

关键词： Dislocation Velocity Exponent and the Strain Rate

Effects of Distribution of Induced Defects on Positron Diffusion

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Journal of materials Science & Technology 2000年第1期16卷 73-75页

作者： Xinzhang ZHOU, Jian JIANG and Chiwei LUNG (international center for {2. physics, Institute of Metal Research, chinese academy of sciences, shenyang 110015, China) international center for {2. physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The effects of distribution of induced defects on the positron diffusion was studied by using the point-source diffusion model and 6 function method.

关键词： Effects of Distribution of Induced Defects on Positron Diffusion

Microstructure characterization of high-energy product Nd-Fe-B thin film

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Progress in Natural Science:materials international 2010年第01期20卷 76-80页

作者： Fang XU~1,Fang YANG~2.Xian-ping DONG~1,Lan-ting ZHANG~1,Wei LIU~2.Zhi-dong ZHANG~2.1.School of materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 2.02.0,China 2.shenyang National Laboratory for materials Science,Institute of Metal Research and international Centre for materials physics,chinese academy of sciences,shenyang 110016,China [a] School of materials Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China [b] shenyang National Laboratory for materials Science Institute of Metal Research and International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

A Si/Mo（50 nm）/Nd-Fe-B（400 nm）/Mo（50 nm）film with relatively high-energy product（BH）max=2.7 kJ/m3)was prepared on a Si substrate heated at 650℃.The microstructure of the film was investigated by X-ray diffractometry（XRD）and high-resolution transmission electron microscopy（HRTEM）.The Nd-Fe-B thin film shows a notable out-of-plane c-axis *** （110）orientated Mo grains is proved to promote the growth of c-axis oriented texture of the Nd2.e14B grains,which is favorable to achieve a high ***-scale spherical Nd-O phases composed of randomly orientated polycrystalline grains and a sharp grain boundary without grain boundary phase between two Nd2.e14B grains are *** coercivity highly depends on a certain amount of Nd-O phase and interface morphology.

关键词： Nd-Fe-B thin films microstructure Nd-O phase magnetic properties

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 {2. 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 {2. 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

Molecular dynamics simulation of kink in 〈100〉 edge dislocation in body centred cubic iron

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chinese Science Bulletin 2007年第16期52卷 2291-2296页

作者： CHEN LiQun1,2.WANG ChongYu2.3,4 & YU Tao2.1 College of sciences,Central South University of Forestry & Technology,Changsha 410004,China 2.Central Iron and Steel Research Institute,Beijing 100081,China 3 Department of physics,Tsinghua University,Beijing 100084,China 4 {2. center for materials physics,chinese academy of sciences,shenyang 110016,China College of sciences Central South University of Forestry and Technology Changsha 410004 China

Using the molecular dynamics method,we have constructed two kink models corresponding to the 〈100〉{010} and 〈100〉{011} edge dislocations (EDs) in body centred cubic (bcc) Fe. It is found that the geometric structure of a kink depends on the type of edge dislocation and the structural energies of the atoms sites in the dislocation core region. The formation energies,migration energies and widths of the kinks in different types of EDs are calculated. The results show that formation and migration of the kink in the 〈100〉{010} edge dislocation are difficult. The 〈100〉{011} edge dislocation moves primarily through kink nucleation,rather than kink migration.

关键词：分子动力学边缘位移铁纽结结构

High-pressure synthesis and properties of CeO_2.ZrO_2.solid solution

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chinese Science Bulletin 2001年第10期46卷 801-806页

作者： XU Dapeng, WANG Quanyong, LU Zhe, LIU Zhiguo, ZHANG Gongmu & SU Wenhui1. Department of physics, Jilin University, Changchun 13002. China 2. international center for materials physics,{2., shenyang 110015, China 3. center for Condensed Matter and Radiation physics, China center of Advanced Science and Technology (World Laboratory), Beijing 100080, China Department of physics Jilin University Changchun China international center for {2. physics Chinese Academy of Sciences Shenyang China center for Condensed Matter and Radiation physics China Center of Advanced Science and Technology (World Laboratory) Beijing China

Using nanoparticles of CeO2.and ZrO2.prepared by the chemical precipitation method as starting materials, the single-phase cubic Ce0.5Zr0.5O2.solid solution (c-Ce0.5Z0.5O2. has been synthesized under 3.1 GPa at 1073 K for the first time. The structure of the c-Ce0.5Zr0.5O2.has not been changed before and after annealing at 773 K for 1 h. Only an unknown EPR signal (g =1.990) has been observed in the c-Ce0.5Zr0.5O2.and not varied after annealing at 773 K for 1 h, which exhibited that there exists no Ce3+ in the c-Ce0.5Zr0.5O2.and the Ce4+ has not been reduced into Ce3+ after annealing. The transport mechanism is ionic for the c-Ce0.5Zr0.5O2. The bulk conductivity (a =1.2.10-5 S/cm at 82. K, σ=2.1 ×10-3 S/cm at 112. K) is the same as that of CeO2. but smaller than that of Y2.3-stabilized ZrO2. A marked curvature at T = 82. K has been observed in the Arrhenius plot of the bulk conductivity. The activation energy below 82. K is lower than that above 82. K, and the reason has been discussed.

关键词： CeO2.ZrO2 nanocrystalline high-pressure and -temperature solid-state reaction solid solution.