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电感耦合等离子体质谱法测定钢中痕量钙亢德华1,于媛君1,王铁1(1.辽宁省鞍山市鞍钢股份有限公司技术中心)摘 要:微波消解钢铁样品后,以电感耦合等离子体质谱(ICP-MS)法测定试液中的痕量钙.实验中使用酸纯化器再次蒸馏的高纯酸以消除Ca的沾污,同时,分析试样前后,使用10%的盐酸对进样系统进行清洗,以去除毛细管,喷雾器和雾化室对钙的吸附.通过考察分析元素的质谱干扰情况,选择丰度高且受干扰程度较小的40Ca+用于分析,并采用动态反应池技术消除40Ar+对40Ca+的质谱干扰.基体Fe的质量浓度不大于1 g/L时......
J. Cent. South Univ. (2016) 23: 2199-2204 DOI: 10.1007/s11771-016-3277-8 Reagent optimization for on-line simultaneous polarographic determination of trace amounts of Cu2+Cd2+ and Co2... 2016 Abstract: Reagents are optimized for the simultaneous determination of trace amounts of Cu2+, Cd2+ and Co2+ in zinc sulfate solution, which contains an extremely large excess of Zn2+. First......
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A topology optimization method based on element independent nodal densityYI Ji-jun(易继军)1, 2, ZENG Tao(曾韬)1, RONG Jian-hua(荣见华)2, LI Yan-mei(李艳梅)3(1. School of Mechanical and Electrical Engineering... of Water Resources and Hydro Power, Changsha 410131, China)Abstract:A methodology for topology optimization based on element independent nodal density (EIND) is developed. Nodal densities are implemented......
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Finite element analysis of rolling process for variable cross-section bladeKONG Xiang-wei(孔祥伟), LI Jia(李佳), LI Bin(礼宾) (School of Mechanical Engineering & Automation, Northeastern University... theory is no longer valid. The complexity and diversity of the blade cross-section determine it impossible to establish an universal theoretical model for the rolling process. Finite element analysis......
. The coating composed of metal oxide, metal hydroxide and hydrate appears to be amorphous. The elements in the coating are Al, Ce, O, Mn and Mg, while the Ce element exists in the forms of Ce3+ and Ce4... formation. Key words: aluminum alloy; conversion coating; rare-earth element  ......
Article ID: 1003-6326(2005)06-1285-05 Effects of rare earth element Ce on solderabilities of micron-powdered Sn-Ag-Cu solder XUE Song-bai(薛松柏)1, YU Sheng-lin(禹胜林)2, WANG Xu-yan(王旭艳)1, LIU..., spreading ratio, wetting time, and melting point, were investigated for verifying the effects of rare earth element Ce on solderabilities of micron-powdered Sn-Ag-Cu solder. The solidus and the liquidus......