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Calculation of interaction parameters from immiscible phase diagram of alkali metal or alkali earth metal-halide system by means of subregular solution model

Zhaochun ZHANG , Deliang CUI , Baibiao HUANG , Xiaoyan QIN , Minhua JIANG

材料科学技术(英文)

The calculation of the model parameters, lambda(11), lambda(12), lambda(21) and lambda(22), was carried out numerically from the phase diagrams for 11 alkali metal-alkali halide or alkali earth metal-halide systems. In addition, artificial neural network trained by known data has been used to predict the values of these model parameters. The predicted results are in good agreement with the calculated ones. The applicability of the subregular solution model to the alkali metal-alkali halide or alkali earth metal-halide systems were tested by comparing the available experimental composition along the boundary of miscibility gap with the calculated ones which were obtained by using genetic algorithm. The good agreement between the calculated and experimental results across the entire liquidus is valid evidence in support of the model.

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密相气力输送颗粒静电波动信号多尺度分析

许传龙 , 王式民

工程热物理学报

在加压密相气力输送实验装置上获得了不同操作条件下煤粉颗粒静电波动信号,并用Hilbert-Huang变换、功率谱进行分析.结果表明:随着表观速度的增加,静电波动信号主峰值的频率增大;静电波动信号希尔伯特-黄变换(Hilbert-Huang)揭示了气固两相流静电信号的非线性和非平稳特征,随气固两相流颗粒相浓度降低和颗粒及表观速度增加,静电波动信号特征尺度由高尺度(低频)向低尺度(高频)转移.多尺度分析有助于认识气固两相流动形态及其转变规律.

关键词: 颗粒静电 , 静电传感器 , 气-固两相流 , Hilbert-Huang变换

1998 COMPREHENSIVE TABLE OF CONTENTS

中国腐蚀与防护学报

N。1Atmospheric Corrosivlty for Steels………………………………………………… .LIANG Caideng HO[I i。-tat(6)Caustic Stress Corrosion Cr。king of Alloy 800 Part 2.The Effect of Thiosul执e……………………………………… KONG De-sheng YANG Wu ZHAO Guo-zheng HUANG De.ltL。ZHANG Yu。。he CHEN She。g-bac(13)SERS slid E16CttOCh6iniC81 Stlldy Of Illhibit1Oli M6ch&tllsth Of ThlollY68 Oil ITOll ID H....

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Shock compression of monocrystalline copper: Experiments, characterization, and analysis

Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing

Monocrystalline copper samples with [001] and [221] orientations were subjected to shock/recovery experiments at 30 and 57 GPa and 90 K. The slip system activity and the microstructural evolution were investigated. Different defect structures, including dislocations, stacking faults, twins, microbands, and recrystallized grains were observed in the specimens. The residual microstructures were dependent on crystalline orientation and pressure. The differences with crystalline orientations are most likely due to different resolved shear stresses on specific crystalline planes. The geometric relationships between the shock propagation direction and crystalline orientation are presented under uniaxial strain. It is shown that the [2 2 11 orientation, by virtue of having fewer highly activated slip systems, exhibits greater concentration of deformation with more intense shear on the primary system. This, in turn leads to greater local temperature rise and full recrystallization, in spite of the thermodynamic residual temperature of similar to 500 K and rapid cooling (within 20 s) to ambient temperature. The profuse observation of microbands is interpreted in terms of the mechanism proposed by Huang and Gray [J.C. Huang, G.T. Gray III, Acta Metallurgica 37 (1989) 3335-3347]. (C) 2009 Elsevier B.V. All rights reserved.

关键词: Shock compression;Shock loading;Slip bands;Microtwins;Microbands;strain rate history;single-crystals;grain-size;constitutive;description;plastic-deformation;mechanical response;deformed metals;loaded nickel;substructure;recrystallization

Mean-field theory for ferroelectricity in Ca(3)CoMnO(6)

Physical Review B

An elastic Ising model for CoMnO(6) chain is proposed to explain the ferroelectricity induced by collinear magnetic order in Ca(3)CoMnO(6), and then a mean-field theory with interchain spin interactions based on this model is developed. With inclusion of the dynamics of polarization domains at finite temperature, we address the rationality of our theory by the good agreement of the calculated electric polarization and dielectric susceptibility with the reported data on Ca(3)Co(2-x)Mn(x)O(6) (x approximate to 0.96) [Y. J. Choi, H. T. Yi, S. Lee, Q. Huang, V. Kiryukhin, and S.-W. Cheong, Phys. Rev. Lett. 100, 047601 (2008)], a typical diatomic Ising spin chain system, while the predicted magnetic susceptibility shows some difference from experiment, the reason of which is discussed.

关键词: calcium compounds;cobalt compounds;dielectric polarisation;ferroelectricity;Ising model;magnetic susceptibility;multiferroics;optical susceptibility;one-dimensional oxides;magnetic-properties;multiferroics;ca3co1+xmn1-xo6

Lu-induced orthorhombic phase in polycrystalline La0.7Sr0.3MnO3

Physica B-Condensed Matter

Polycrystalline La0.5Lu0.2Sr0.3MnO3 samples prepared by thermal decomposition are investigated by means of electron diffraction and high-resolution transmission electron microscopy. Besides rhombohedral La0.7Sr0.3MnO3 phase (R-phase) and hexagonal LuMnO3 phase (H-phase) reported by Huang, unexpectedly, an orthorhombic lattice (O-phase) with space group Pnma is observed in the interior of R-phase grain. The lattice parameters of the orthorhombic unit cell are a(o) = 5.44 angstrom, b(o) = 7.65 angstrom and c(o) = 5.48 angstrom The formation of O-phase results from a(-)b(+)a(-) type orthorhombic distortion of MnO6 octahedra induced by partial substitution of Lu3+ for La3+. Meanwhile, based on image simulation of the interface between R and O-phases, the atomic bonding on the interface is particularly discussed. (c) 2005 Elsevier B.V. All rights reserved.

关键词: orthorhombic lattice;octahedral;substitution;atomic bonding;la0.7-xluxsr0.3mno3 perovskites;transport-properties;magnetoresistance;films

Effects of A-site doping on microstructure and phase separation of La0.5RE0.2Sr0.3MnO3 (RE=Eu, Ho, Yb, Lu)

Materials Letters

Phase separation and microstructure of La0.7Sr0.3MnO3 doped with rare earth elements (Eu, Ho, Yb and Lu) are studied using X-ray diffraction (XRD) and transmission electron microscopy (TEM). Composition and diffraction analyses demonstrate that the ionic radius of doping element plays an important role in the crystalline structure and the lattice constants of the secondary phase. When La 3 is replaced partly by Eu3+ or Ho3+, orthorhombic perovskite structure with space group Pnma is formed due to the distortion Of MnO6 octahedra. Different from the phenomenon observed by Huang et al., however, the hexagonal non-perovskite structure (YbMnO3 and LuMnO3) has appeared when La3+ and Sr2+ are substituted completely by Lu or Yb (c) 2005 Elsevier B.V. All rights reserved.

关键词: ionic radius;crystalline structure;lattice constants;orthorhombic;perovskite;hexagonal non-perovskite;magnetoresistance;perovskites;films

有限变形下闭孔泡沫铝的非线性压缩行为

陈伟 , 卢子兴

复合材料学报 doi:10.13801/j.cnki.fhclxb.20151204.002

基于 Huang(北京大学)和 Wang(北京大学)的理论和热力学第二定律,研究了有限变形下闭孔泡沫铝的非线性压缩行为。通过引入内变量及内变量的演化方程,给出了有限变形下同时考虑细观结构参数和黏性效应的有效幂律势函数及相应的应力表达式。基于所提出的理论模型,通过算例讨论了细观力学方法、孔隙度和黏性效应对泡沫铝应力-应变曲线的影响规律。结果表明:模型预测与实验结果基本一致,且随着黏性系数的增大,考虑黏性效应的模型预测趋向于未考虑黏性效应时的模型预测。

关键词: 球形闭孔高密度泡沫铝 , 有限变形 , 有效幂律势函数 , 非线性力学行为 , 黏性

基于HHT的延期时间识别法在精确短延时爆破优化中的应用

史秀志 , 邱贤阳 , 周健 , 陈新 , 范玉乾 , 卢二伟

中国有色金属学报(英文版) doi:10.1016/S1003-6326(16)64310-8

延时爆破中延期时间的准确识别对于优化爆破设计和降低爆破振动效应具有重要作用。以超大断面调压竖井导井爆破为例,对比分析了基于Hilbert?Huang 变换(HHT)的EMD识别法和瞬时能量识别法在精确短延时爆破中的延期时间识别能力,发现EMD识别法的识别率在80%以上,而瞬时能量法识别率低于25%。通过单孔爆破振动信号瞬时能量分析表明,瞬时能量识别法适用于延期时间大于瞬时能量峰值半周期的微差爆破。将 EMD识别法应用于紫金山露天矿微差爆破延期时间识别,为降低爆破振动和爆破大块率,以识别结果为依据对爆破参数进行了优化。现场实测数据表明:通过优化起爆雷管和延期时间,相同单孔药量下爆破振动降低30%以上;结合压渣爆破和前排抵抗线优化,爆破块度成功降低到3%以下。研究结果证明了基于HHT的延期时间识别法能有效实现爆破设计的优化,该识别方法对于其他类似爆破工程的设计优化具有一定的参考价值。

关键词: 延期时间识别 , 短延时爆破 , 精确起爆 , 爆破降振 , Hilbert-Huang变换(HHT)

三向受压下单向复合材料层板破坏的细观力学分析

陈滨琦 , 曾建江 , 王玉青 , 童明波

复合材料学报 doi:10.13801/j.cnki.fhclxb.20160706.001

本文从细观力学出发,提出一种新的基于物理失效机制的细观失效准则.该准则基于Mohr-Coulomb准则并侧重考虑了压缩载荷下组分材料的损伤模式和失效机制,指出压缩失效时压应力会阻碍断裂面的剪切破坏,并深入研究了纤维压缩失效模式,在纤维折断失效准则中引入纤维折断破坏面上剪切强度的概念.采用本文提出的准则对WWFEII(the Second World Wide Failure Exercise)中单向板算例进行失效预测和定量评估,并与Puck、Pinho、Cuntze、Carrere、Tsai-Ha、Hansen和Huang准则的预测结果进行对比,表明在三向载荷下本文提出的细观失效准则在8种失效准则中拟排名第一.研究了静水压力对基体强度的影响,得出影响因子仅与单轴压缩断裂角有关的结论.探讨了WWFEII各强度准则间关于失效包线是“张开”还是“封闭”的重要分歧,认为复合材料在三向压应力状态下失效包线是否为“张开”和“封闭”没有统一的标准答案,而是与复合材料的纤维体积含量、纤维和基体的力学性能、基体随静水压力力学性能的变化及基体的单轴压缩断裂角有关.

关键词: 复合材料 , 细观力学 , 失效准则 , 纤维折断 , 静水压力

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