DU Yong Q.S.Ran JIN Zhanpeng G.Effenberg DING Wei Dept.of Materials Science and Engineering
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Central-South University of Technology
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Changsha
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410083
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ChinaMax-Planck-Institut fur Metallforschung
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Institut fur Werkstoffwissenschaften
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Heisenbergstrasse 5
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D-7000
材料科学技术（英）
Lattice stability of Be is estimated,and interaction parameters for the liquids in the Al-Be and Be-Si systems are obtained using phase dia- gram data from literatures.Using the obtained parameters and the lattice stabilities of Al and Si given in the literatures,the Al-Be and Be-Si phase diagrams are calculated.By means of Kohler's for- mula the Gibbs energy for the liquid phase in the Al-Be-Si ternary system is extrapolated.The calcu- lation shows that no excess ternary term is necessa- ry for the thermodynamic description of the system. The liquidus projection,isothermal section at 1273 K,as well as vertical sections at 94 and 88 wt-% Al and 2 wt-% Be are calculated.The calcu- lated results are in reasonable agreement with the experimental data available.
关键词:
thermodynamics
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null
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null
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null
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null
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null
European Physical Journal B
Moving nonlinear localized vibrational modes (i.e. discrete breathers) fur the one-dimensional homogenous lattice with quartic anharmonicity are obtained analytically by means of a semidiscrete approximation plus an integration. In addition to the pulse-envelope type of moving modes which have been found previously both analytically and numerically, we find that a kink-envelope type of moving mode which has not been reported before can also exist for such a lattice system. The two types of modes in both right- and left-moving form can occur with different carrier wavevectors asd frequencies in separate parts of the omega(q) plane. Numerical simulations are performed and their results are in good agreement with the analytical predictions.
关键词:
diatomic chains;stability;solitons;equation
Acta Chimica Sinica
For the translocation of a diblock copolymer chain through a nanopore in a membrane with two translocation orders, the free energies under different conditions were given, and then the mean first-passage time (MFPT) was obtained by solving the Folcker-Planck equation. The corresponding numerical calculations show that, when the copolymer chain transports from the region of good solvent to that of poor solvent, the translocation order that the block without coil-blob transition transports first is prior to the other. At a given order, it was found that the chemical potential, coil-blob transition, composition of the diblock copolymer chain and the translocation rate played an important role in the translocation. The present studies are expected to provide available clues to the translocation of real biopolymer chain.
关键词:
diblock copolymer chain;translocation;mean first-passage time (MFPT);coil-blob transition;single polymer-chain;dna transport;discrimination;molecules;channel;pore;hole
赵亮
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刘林华
工程热物理学报
本文采用有限容积法数值模拟了在电动效应作用下微通道内流体的流动特性.分别采用Poisson方程和Nernst Planck方程计算电动势和离子浓度分布.结果表明在双电层相互交叠的情况下,微通道内轴向的流动电势先减小后增大,并逐渐趋于定值,从而导致了轴向电动效应不断增强.
关键词:
微流动
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微通道
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双电层
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数值模拟
杨成雄
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王士伟
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严秀平
应用化学
doi:10.11944/j.issn.1000-0518.2016.09.160211
以吸附等温线、动力学和热力学等方法研究了金属-有机骨架对苯二甲酸酯-铝[MIL-53(Al),MIL:Materials of Institut Lavoisier]对水中邻硝基苯酚、苯酚和邻苯二酚的吸附行为.MIL-53 (Al)对上述酚类化合物的吸附符合准二级吸附动力学模型,且包含表面吸附和孔内扩散两个过程.吸附热力学结果表明,MIL-53(Al)对酚类化合物的吸附是自发的,且为吸热和熵增加过程.在40℃条件下,MIL-53 (Al)对邻硝基苯酚、苯酚和邻苯二酚的吸附量分别为78.6、30.5和16.5 mg/g.
关键词:
金属-有机骨架
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吸附
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酚类化合物
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对苯二甲酸酯-铝
W. L. Zhou
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J. T. Guo
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R.S. Chen and J. Y Zhou(Institute of Metal Research
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The Chinese Academy of Sciences
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Shenyang 110015
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China)(Department of Materials Engineering
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Dalian University of Technology
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Dalian 116024
,
China)
金属学报(英文版)
Our previous investigation examines the soperplastic behavior of an extruded Ni-28.5Al-20.IFe alloy. Its tensile properties were determined at temperature from 1123Kto 1323K and initial strain rates from 1.0{x 10-2s-1 to 1.04x 10-4s-1. A maximumelongation of 233K was obtained at 1123K and a strain rate Oj 5.2x 10-4s-1. Fur-thermore, microstructural features, such a8 decrease in the avempe gmin Bize afier de-formation at 85dC and 98dC the presence oj many dislocationthee gmins adjacentto grains with a high dislocation density, indicate that dynamic recrystallization hasoccuwed as an decient accotnmodation mechanism. SEM examination Of the fracturesample afier saperplastic defOrmation revealS many voids on the hecture sudece. Bycoerelating with the results Oj TEM observation, it is sopested that the soperplasticdejormation in this alloy should be controlled by a gmin boundarp sliding-based mech-anism accommodated by the movement oj dislocation and dynamic recrpstallization.
关键词:
Ni-Al-Fe intermetallics
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null
Acta Materialia
The effect of alloying elements Cr and Mn on the cohesion of the gamma -iron Sigma 11[1(1) over bar 1]/(11(3) over bar) grain boundary (GB) is investigated based on the thermodynamic model of Rice-Wang by using the first-principles density functional theory. The electronic properties are studied fur Cr/Fe and Mn/Fe systems. In these systems, the chemical effect of Cr and Mn is in favor of enhancing the cohesion of the grain boundary due to the anisotropic bonding which weakens the bonds in the grain boundary plane, but strengthens those in planes perpendicular to the grain boundary. However, the structural relaxation effect is detrimental to the cohesion of the grain boundary. After synthesizing these two effects, Cr can act as a cohesion enhancer and Mn is an embrittler. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.
关键词:
computer simulation;gamma-iron;grain boundaries;segregation;electronic-structure;phosphorus segregation;stainless-steel;embrittlement;austenite;boron;manganese;sulfur;carbon;ni3al
Physica Status Solidi B-Basic Research
The influences of the squeezing-antisqueezing effect arising from variations of the electron density and motion of polarons and nonadiabatic phonon fluctuations on the properties of the ground state and the binding energy of the polaron in the Holstein model of coupled one-dimensional electron-phonon systems with spin 1/2 in the cases of high and low electron densities have been studied by using the Bogolyubov transformation and a new ansatz fur states that includes correlation effects among the one-phonon coherent and two-phonon squeezed and polaronic states. The results obtained show that the squeezing-antisqueezing (correlation) effect results in that the ground state energy of the systems is significantly lowered, and the binding energy of the polaron is considerably increased. Thus, the stability of the systems and of the polaron are obviously enhanced in such a case when compared with the uncorrelated case. This shows that the ground state determined by the new state ansatz is most stable, and the new ansatz introduced here is very relevant for the coupled electron-phonon systems, especially in strongly coupled and largely squeezed cases.
关键词:
molecular-crystal model;bipolaronic superconductivity;quantum;fluctuations;phase-diagram
