材料期刊网

Bonding Characteristics of the Intermetallic Compound Al_3Ti+Cr

Senying LIU , Rongze HU , Dongliang ZHAO and Chongyu WANG (Central Iron and Steel Research Institute , Beijing 100081 , China)Ping LUO (National Research Center for Certified Material , Beijing 100013 , China)Zhongjie PU (Florida International University , Miami

材料科学技术（英文）

Based on our structural model and a tight-binding Hamiltonian the eIectronic structure has been calculated by use of a recursion method (RM) for two models of the tetragonal DO22 and the cubic Ll2 crystal structures in Al3Ti+Cr for contrast, from which bonding characteristics have been discussed. The results for the interaction energy (IE) show that Cr prefers to replacing Al site. Cr partly replacing Al can change the IE between the atoms and make the constriction of lattice constant c and the elongation of lattice constant a for the DO22 and thereby may induce the change of crystal structure from DO22 to L12. The results for bond order integral (BOI) and IE between the atoms also show that the strong (110) directional Cr-Ti bondings are existed.Thus, Al3Ti-base intermetallic compounds with addition of the Cr atom still remain brittle.

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Pu(Ⅳ)、Pu(Ⅴ)在不同质地砂土中的分配

于静 , 司高华 , 黄云贵 , 刘东旭

应用化学 doi:10.3724/SP.J.1095.2011.00388

Pu(Ⅲ)、Pu(Ⅳ)、Pu(Ⅴ)和Pu(Ⅵ)在自然水的pH和Eh(氧化还原电势)值范围内能够共存.在自然环境中主要以Pu(Ⅴ)的PuO2(H2O)n+和Pu(Ⅳ)的Pu(OH)4形式存在.采用静态法测定了Pu(Ⅳ)和Pu(Ⅴ)在砂土介质中的分配系数Kd,Pu(Ⅳ)和Pu(Ⅴ)在砂土中的分配系数范围分别为5.5×103～4×104mL/g和3.2×103～1.1×104mL/g.表明在砂土介质中Pu(Ⅳ)的分配系数(Kd)大于Pu(Ⅴ)的,并且分配系数随砂土介质中粘土矿物含量的增加及介质颗粒粒径减小而增大.

关键词: Pu(Ⅳ) , Pu(Ⅴ) , 砂土 , 分配系数

γ-射线引发PU接枝HEMA的研究

周向东 , 刘朋生

高分子材料科学与工程

聚氨酯(PU)在氮气保护下经60Co-γ射线照射后表面产生自由基,然后浸入到甲基丙烯酸-β-羟乙酯(HEMA)溶液中接枝,再使PU和HEMA的接枝共聚物(PU-g-PHEMA)在催化剂作用下接枝抗静电剂TN,由此合成表面具有耐久性抗静电的聚氨酯(PU-g-PHEMA-g-TN).通过FT-IR、ESCA、SEM等手段表征了PU辐射接枝HEMA的产物,并研究了影响PU接枝HEMA的主要因素.结果表明,HEMA的接枝率随辐射剂量和单体浓度的增加而增加,随剂量率的增加而减小,低浓度的溶剂(乙醇)有利于接枝.

关键词: γ-射线 , 聚氨酯 , 接枝 , 甲基丙烯酸-β-羟乙酯

The Second International Conference on HSLA Steels Beijing,China,October 1990 Organized by THE CHINESE SOCIETY OF METALS

金属学报(英文版)

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La,Ce,Pr,Nd and Sm concentrations in Pu'er tea of Yunnan,China

稀土学报(英文版) doi:10.1016/S1002-0721(09)60170-8

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STATISTICAL EVALUATION OF CRITICAL INCLUSION FACTOR FOR SECONDARY RECRYSTALLIZATON IN 3%Si STEEL Lecturer,Department of Materials Engineering,Southwestern Jiaotong University,Chengdu 610031,China

LI Shuchen Southwestern Jiaotong University , Chengdu , ChinaCHEN Mengzhe KE Jun University of Science and Technology Beijing , Beijing , China

金属学报(英文版)

On the basis of statistical data of MnS in the conventional 3% Si steel sheeets after various annealing processes,the critical inclusion factor has been evaluated to be 20 mm~(-1).The inhi- bition of MnS to grain growth has been exactly described.

关键词: 3%Si steel , null , null

CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,University of Science and Technology Beijing,Beijing 100083,China

QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing , Beijing , China

金属学报(英文版)

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词: stress corrosion cracking , null , null , null

Introduction to atmospheric corrosion research in China

Science and Technology of Advanced Materials

In this paper, we introduce the research on atmospheric corrosion in China. We describe the climate characteristics and the classification of atmospheric corrosivity across the whole country. We also describe the rusting evolution under simulated wet/dry cyclic conditions. (C) 2007 NIMS and Elsevier Ltd. All rights reserved.

关键词: atmospheric corrosion;corrosivity;rusting evolution;weathering steels;rust;mechanism;so2;o-3;no2

Recent Advances of Laser Coating Technology in China

LIANG Yong LI Ruiguo Institute of Metal Research , Academia Sinica , Shenyang 110015 , ChinaInstitute of Corrosion and Protection of Metals , Aademia Sinica , Shenyang , 110015 , China

材料科学技术（英文）

Recent advances in laser coating technology including laser cladding,laser surface alloying and laser vapour deposition in China are reviewed in this paper.

关键词: laser , null , null , null , null

PU/PMMA IPN的阻尼行为研究

秦东奇 , 王静媛 , 于小强 , 李峰 , 汤心颐

高分子材料科学与工程

采用全自动扭辫仪和驻波管对PU/PMMA IPN 体系的阻尼行为进行了研究.TBA结果表明,填料的最佳填加量为10%.吸音系数测试表明,常温时该种结构的IPN材料的吸音系数与频率近似成峰形,最大吸收在3000 Hz左右.最好的吸音材料的吸音系数峰值为50%以上.

关键词: 阻尼因子 , 吸音系数 , 填料 , 阻尼行为