SUN Zuqing
,
MAO Weimin
,
CHAI Shuyan
,
YANG Wangyue
,
HUANG Yuanding(University of Science and Technology Beijing
,
Beijing 100081. China)RAABED
,
KEICHELJ(Institut fur Metallkunde und Metallphysik. RWTH Aachen
,
Germany)
金属学报(英文版)
The rolling and recrystallization texture of B2 type Fe3Al based alloys were systematially investigated by ODF. The results showed that the rolling texture consisted of a strong β-fibre close to {111} and a {001} <110> texture. In annealing process the rolling texture was strengthened at recovery stage and gradually disappeared during primary recrystallization. A strong shear texture was produced by only 20% Pass reduction, indicating that the Fe3Al is sensitive to shear stress. The corresponding room temperature tensile properties were measured. A correlation between texture mode and room temperature mechanical properties was observed.
关键词:
: Fe3Al
,
null
,
null
,
null
祁明旭
,
丰镇平
,
工程热物理学报
本文对Aachen一级半轴流式透平进行了准定常及非定常流动的数值模拟,讨论了引发动静干涉效应的主要因素,分析了非定常效应对叶栅通道中脉动速度、气流角、型面压力分布以及损失结构的影响.结果表明,对于Aachen透平而言,上游叶片排的尾迹区及二次涡是引发下游叶栅通道流场强非定常特性的最主要因素,引起了脉动速度、型面压力、攻角以及损失的较大变化,从而对透平级性能产生较大的影响.
关键词:
准定常
,
非定常
,
动静干涉
,
损失
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
王晓东
,
邓啟家
,
康顺
工程热物理学报
本文以Aachen 1.5级轴流涡轮为研究对象,采用Fine/Turbo软件包分别模拟了模拟了三种不同流量工况下,平均叶顶间隙高度比(平均叶顶间隙高度与叶片高度的比值)分别为0.7％、1.3％、1.9％时其转子存在静偏心时的三维定常流场.在验证与确认的基础上,分析了转子偏心对激振力和涡轮的气动性能的影响.转子的激振力随偏心距的增大而线性增加,且间隙尺度越大,增加越快.在偏心较为严重时,适当增大间隙尺度,有利于削弱涡动的堵塞效应,降低泄漏损失.
关键词:
涡轮
,
偏心
,
间隙
,
激振力
,
数值模拟
乔蕊
,
李靖
量子电子学报
doi:10.3969/j.issn.1007-5461.2015.03.003
针对人脸识别中存在遮挡而影响识别性能的问题,提出了一种利用快速加权主成分分析(FW-PCA),检测遮挡区域的鲁棒人脸识别算法.利用FW-PCA检测输入图像的遮挡区域,将其与图库图像的遮挡区域进行比较;利用局部二值模式匹配确定最优权重系数,利用相位相关算法匹配确定遮挡掩码;计算每个测试图像的匹配得分,并利用最近邻分类器完成人脸识别.在FRGC2和UND人脸库上的实验结果表明,此算法的识别率可高达99.6％,相比其他几种较新的人脸识别算法,取得了更好的识别性能.
关键词:
图像处理
,
人脸识别
,
遮挡区域检测
,
快速加权PCA
,
相位相关算法
,
局部二值模式
杨成雄
,
王士伟
,
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
,
吸附
,
酚类化合物
,
对苯二甲酸酯-铝
W. L. Zhou
,
J. T. Guo
,
R.S. Chen and J. Y Zhou(Institute of Metal Research
,
The Chinese Academy of Sciences
,
Shenyang 110015
,
China)(Department of Materials Engineering
,
Dalian University of Technology
,
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
,
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
