共查询到20条相似文献,搜索用时 9 毫秒
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《稀有金属(英文版)》1999,18(3)
CONTENTS1ExtractiveMetallurgy(7)2MetalMaterialsandTechnology(7,8)99-1-7 ResearchofCyclocarbonateExtractantsforPreciousMetals Sixcyclocarbonateextractantsofaserieshavebeensynthesized.Theirextractionproperties,suchasextractionspeed,phaseseparati… 相似文献
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《稀有金属(英文版)》1999,(1)
CONTENTS1ExtractiveMetalurgy(1~4)2MetalMaterialsandTechnology(1~3)3Semiconductor(1~2)4MetalPhysics(1)5ChemicalAnalysisan... 相似文献
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B. W. Zhang Z.M. Ren Y.B. Zhong K. Deng K.D. XuShanghai Enhanced Laboratory of Metallurgy Shanghai University Shanghai China 《金属学报(英文版)》2002,15(5):416-424
The electromagnetic field under applied AC and DC current in round and rectangular pipe was systematically investigated, then a concept of "equivalent current density" was proposed for evaluating the inhomogeneous electromagnetic pinch force, and the mono-component removal efficiency and the overall removal efficiency of inclusion were formulated. It is founded that flat pipe is superior to round pipe for the electromagnetic removal of inclusion, and DC current can get a higher removal efficiency than A C current due to absence of skin phenomenon. Under usual condition, a removal efficiency of 52% for 10μm inclusion or more than 92% for 20μm inclusion can be achieved by imposing a current density of 3×106A/m2 in a flat pipe. 相似文献
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稀土元素在金属材料中的作用与机理 总被引:45,自引:4,他引:45
杜挺 《中国有色金属学报》1996,6(2):13-18
该文作者从1961年开始进行稀土元素在铁基、镍基、铜基、铝基等约百个2~4元金属溶液体系的热力学、相平衡及在20多个金属材料(包括稀土-铁超磁致伸缩材料)中的作用与应用研究,该文依据作者所在科研组的研究成果并参考一些文献,说明了稀土元素在金属材料中的作用和机理 相似文献
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本文是研究含氧纯铁中加入La,Ce,Pr,Nd与混合稀土金属后生成的夹杂物.通过金相法、岩相法、x射线衍射法以及电解分离与化学分析方法,研究了各种稀土夹杂物的光学性质与化学性质,以及它们的晶体结构.实验结果肯定了含氧纯铁中加入稀土金属后生成的夹杂物类型有:CeO_2,Ce_2O_3,La_2O_3,Ce_2O_2S,La_2O_2S,CeS,LaFeO_3,FeO·La_2O_3…等,并讨论了它们的生成过程. 相似文献
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WANG Xiaotian YAO Yinliang SHAO Tanhua Xi′an Jiaotong University Xi′an China 《金属学报(英文版)》1991,4(3):188-193
The microstruetural transformation of steels:20SiMn2V,20SiMn2VRE,40SiMn2V and40SiMn2VRE during quenching and tempering have been examined by TEM,X-raydiffraction and dilatometer.It was shown that the addition of rare earth metals not only canrefine the austenite grains of the low or medium carbon steels and packet of lath martensiteand lath size,lower the M_s temperature,but can also raise the relative percentage of disloca-tion substructure of martensite in medium carbon steel,but there is little effect on volume frac-tion and thermal stability of retained austenite quenching and tempering structure of low ormedium carbon steels.The rare earth metals may remarkably inhibit the decomposition of lowcarbon martensite during low temperature tempering,retard the precipitation of cementiteplates in lath grains and delay the spheroidization of carbides.They may also restrain obvious-ly the precipitation and spheroidization of cementite in medium carbon martensite during hightemperature tempering. 相似文献
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No Author 《金属学报(英文版)》1990,3(11):367-367
Congratulate Professor James C.M.Li,a celebrated scientist of Chinese descent,on his Winning of the 1990 Acta Metallurgica Gold Medal 相似文献
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<正> 中国金属学会第三届焊管学术年会于1988年4月10日至15日在云南昆明市召开。会议由中国金属学会轧钢学会钢管学术委员会焊管学术组主持,来自全国有关高等院校、研究院所、设备制造厂家和焊管生产厂家共75个单位的111名代表参加了会议。 相似文献
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Z.J.Ding K.Salma Z.M.Zhang 《金属学报(英文版)》2005,18(3):345-350
The full energy distribution of backscattered electrons from the elastic peak down to the true-secondaty electron peak for heavy metals, Ta, W, Pt and Au, in Auger electron spectroscopy in the EN(E) mode has been studied with a Monte Carlo simulation method, which includes cascade-secondary-electron production. The simulation model is based on the use of a dielectric function for describing inelastic scattering and secondary excitation, and on the use of Mott cross sections for elastic scattering. A systematic comparison between the calculated and experimental spectra measured with a cylindrical mirror analyzer has been made for primary energies ranging from 1 to 5keV. Excellent agreement was obtained for these heavy metals on the backscattering background at primary energies in the keV region. A significant contribution of cascade secondary electrons to the measured spectra on the low-energy side was found. 相似文献
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选择了鋅、鎘、錫、鉛、銻和鉍六种純金属,一种鉛-錫(50%重量百分数)共晶型合金和一种銻-鉍(10%重量百分数)固溶体型合金作研究对象,着重研究了超声波对它們凝固过程的影响,并且从其中选取鋅、鎘、銻、鉍和銻-鉍合金观察了晶粒細化和超声波的关系。結果是:超声波使所有这些金属与合金的冷却速度減緩和凝固时間延长,对于有效冷度的銻、鉛-錫和銻-鉍合金的过冷度减小,一般情况下,超声波可使宏观晶粒細化,随功率增加晶粒細化随金属而异。所有这些是由于超声波在金属中传播时,声能变热能和使欲凝固分子做平行于結晶面振动的結果。 相似文献
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有机涂层阴极剥离作用研究进展 总被引:2,自引:0,他引:2
介绍和评述了阴极剥离对有机涂层劣化和涂层下金属腐蚀过程影响的研究现状,讨论了影响阴极剥离发生与发展的因素、阴极剥离作用机理和提高有机涂层耐阴极剥离的途径.同时综述了研究有机涂层阴极剥离的测试技术和研究方法. 相似文献
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在溶液理论的基础上,提出了一种新的热力学处理方法,用于计算有机相组分活度系数、测定金属溶剂萃取反应热力学平衡常数以及预测金属萃取平衡分配.用纯热力学方法研究了:TBP-UO_2Cl_2,TBP-UO_2(NO_3)_2和(C_7H_(15))_2SO-UO_2(NO_3)_2等三种中性溶剂金属萃取体系.检验和比较了七种模型,其中以 Scat-chard-Hildebrand 和 Guggenheim 模型对实际计算更为简便,这两种模型不仅能用于三组分有机相,且能用于四组分有机相. 相似文献
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活性元素对合金高温氧化的作用机制 总被引:14,自引:1,他引:14
合金内添加微量活性元素可以显著改善合金的抗高温 氧化性能.活性元素效应已在高温合金和抗高温氧化的防护涂层上得到大量应用,而其微观 作用机制尚未完全明了.本文综述了已有的活性元素微观作用模型,并分析了各种模型存在 的缺点,对国内的研究成果也作了总结.同时指出未来着重解决的问题. 相似文献