H.F.Yu 1)
,
P.Q.Liu 1) and W.H.Wang 2) 1) Department of Materials Science and Engineering
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Shenyang Architectural and Civil Engineering Institute
,
Shenyang 110015
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China 2) Department of Airport
,
CAAC Eastnorth Management
,
Shenyang 110043
,
China
金属学报(英文版)
The properties of a new magnesium Oxychloride cement (MOC) material formed by silica fume uniformly mix in MOC paste was presents. The influence of silica fume on the water resistance and compressive strength of MOC paste was invesigated in this study. It is shown that when 30 weight percent of silica fume is added to the MOC paste, a high strength and water resisting new material with 112MPa compressive strength and 1 00 water resisting coefficient could by obtained.
关键词:
silica fume
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null
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null
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null
Andrej Atrens
材料科学技术(英文)
Corrosion research by Atrens and co-workers has made significant contributions to the understanding of the service performance of engineering materials. This includes: (1) elucidated corrosion mechanisms of Mg alloys, stainless steels and Cu alloys, (2) developed an improved understanding of passivity in stainless steels and binary alloys such as Fe-Cr, Ni-Cr, Co-Cr, Fe-Ti, and Fe-Si, (3) developed an improved understanding of the melt spinning of Cu alloys, and (4) elucidated mechanisms of environment assisted fracture (EAF) of steels and Zr alloys. This paper summarises contributions in the following: (1) intergranular stress corrosion cracking of pipeline steels, (2) atmospheric corrosion and patination of Cu, (3) corrosion of Mg alloys, and (4) transgranular stress corrosion cracking of rock bolts.
关键词:
Stress corrosion cracking
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null
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null
K. Zhang
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W.P. Shen
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C.C. Ge
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null
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null
金属学报(英文版)
W / Cu functionally gradient materials (FGMs) containing 1% La2O3 and 1% TiC were prepared using graded sintering under ultra-high pressure (GSUHP). The specimens have been found to exhibit low porosity (11.57% and 11.35%, respectively). Shearing strength of the specimens between layers is good. Moreover, the specimens have still demonstrated good performance in testing thermal-shock resistance. When power density of laser is 200MWm-2, the specimens have been tested for thermal-shock resistance (1000 times); the specimens that contained 1% La2O3 were not subjected to damage, whereas those that contained 1% TiC began to crack. Finally, effect of additives on thermal-shock resistance was also preliminarily discussed.
关键词:
W/Cu
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null
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null
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null
LIU Guoquan Department of Materials Science and Engineering
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University of Science and Technology Beijing
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100083
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China.
材料科学技术(英文)
Quantitative analysis of populations having a geometric structure,which has developed into a special scientific subject called microstructology or stereology,is of great importance to the characterization and evaluation of microstructures and their evolution in various processes.This paper, besides a brief discussion on those topics such as the recent developments of computer assisted image analysis,mathematical morphology,and fractal analysis,will mainly focus on the scope,fundamen- tals,present status,and perspectives of classical stereology.Several case examples of its application to materials science will also be given.
关键词:
stereology
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null
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null
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null
李琳
,
辛璟焘
,
刘静
,
戴康
,
沈异凡
量子电子学报
doi:10.3969/j.issn.1007-5461.2008.03.003
利用一步激发的饱和吸收光谱技术测量了激发态Rb(5P<,3/2)态的原子密度,室温下的Rb-H<,2混合蒸气被780nm激光激发,在激光线宽远小于Doppler线宽条件下,在激光功率40μW至5mw的范围内,测量了吸收系数,得到了5P<,3/2态的速度选择布居数密度.通过Rb空心阴极灯发出的5D→5P<,3/2窄谱线的吸收测量,也可以测得5P<,3/2态的原子密度,二种测量方法所得结果符合得很好.当氢气压为100Pa时,约8%基态原子被单模半导体激光器激发到5P<,3/2态.
关键词:
光谱学
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速度选择粒子数密度
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饱和吸收
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RbH2混合蒸气
杨赞中
,
廖立兵
,
杜洪兵
人工晶体学报
doi:10.3969/j.issn.1000-985X.2005.01.021
为了探讨化学成份对VPO体系孔道结构化合物结构稳定性的影响,根据酸碱平衡原理进行了合成实验设计;利用V2O5、H3PO4、H3BO3等简单的无机前驱物、乙二胺作结构导向剂,水热法合成了孔道结构钒硼磷酸盐化合物(H3NCH2CH2NH3)2(H3NCH2CH2NH2)[VⅢ(H2O)2(VⅣO)8(OH)4(H(P,B)O4)4((P,B)O4)4(H2O)2]·3H2O(简称V9(P,B)8-en).典型的反应起始物摩尔比为n(V2O5):n(H3BO3):n(H3PO4):n(en):n(H2O)=0.89:3.50:3.50:3.60:265(pH值为6.5),在175℃、自生压力条件下恒温晶化6.5d(最终pH值为5.9).通过电子探针、粉末X射线衍射、红外吸收光谱、原子占位度修正等方法,对产物的化学成份、物相及其结构等进行了实验研究.证实V9(P,B)8-en为V9P8-en的类质同象化合物,不同晶粒中B与P的含量有差别,B与P之比为O.1:7.9~2.54:5.46(原子比),但恒有V:(P+B)≈9:8.表明通过合理设计和控制合成条件,可在保持V9P8-en基本结构不变的前提下通过同晶取代引入新的化学成份,并由此探讨成份与结构稳定性的关系.
关键词:
VPO体系
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孔道结构
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水热合成
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分子自组装
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类质同象
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钒硼磷酸盐
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结构稳定性
姚春发
,
李财富
,
刘志权
,
尚建库
无机材料学报
doi:10.3724/SP.J.1077.2011.00649
以无机盐为前驱体, 利用溶胶?凝胶法固溶合成了(1-x)Pb(Fe2/3W1/3)O3-xPb(Mg1/2W1/2)O3多铁性固溶体. XRD分析表明, 在0≤x≤1.0的掺杂范围内, 700℃煅烧所得产物都具有钙钛矿结构; x=0时得到的纯Pb(Fe2/3W1/3)O3为长程无序结构, x=1.0时可获得完全有序的纯Pb(Mg1/2W1/2)O3相, 其单胞为Pb(Fe2/3W1/3)O3单胞的2倍; 当0<x<1.0时, (1-x)Pb(Fe2/3W1/3)O3-xPb(Mg1/2W1/2)O3固溶体也为有序结构, 出现1/2 (111)及1/2 (311) XRD衍射峰, 且强度随掺杂系数x的升高逐渐增大. TEM分析证实, 煅烧产物为具有钙钛矿结构的单相固溶体, 而非两相复合物; 固溶相形貌以立方颗粒为主, 随掺杂量增加其晶胞常数线性增大, 而晶粒尺寸先减小后变大. 性能测试发现, 固溶相的磁学性能随x的增加而逐渐下降, 起因于抗磁性的Pb(Mg1/2W1/2)O3破坏了Pb(Fe2/3W1/3)O3原有的价键结构所致.
关键词:
多铁性材料
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perovskite
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Sol-Gel
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ordering
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magnetic property