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41.
采用HNO3+HCl混合酸消解体系敞口消解试样,选取74Ge作为测定48Ti,52Cr,59Co,61Ni的内标元素,建立了微合金钢中微量元素钛、铬、钴、镍的电感耦合等离子体质谱(ICP-MS)测定方法。该方法线性关系良好(相关系数r=0.99985~0.99998),检出限为6pg·g-1~39pg·g-1,平均加标回收率达到98%~102%,方法精密度好,相对标准偏差(n=9)在0.47%~2.04%之间。所建立的分析方法实现了对微合金钢样品中4种微量元素的测定,实际样品的测定结果与参考值相符。 相似文献
42.
Serpil Yenisoy-Karaka? 《Food chemistry》2012,132(3):1555-1561
Cadmium, copper, iron, lead, tin and zinc were determined in tomato paste samples by using high resolution inductively coupled plasma mass spectrometry. This study was a part of Proficiency Testing scheme conducted by National Metrology Institute (UME) of Turkey. The method was validated. The percentage relative errors obtained for each element ranged between 1.4% and 9.0% for NIST SRM 1573a, tomato leaves. Measurement uncertainties of all elements were calculated by applying bottom-up approach. The calculated percentage relative uncertainties for the elements were between 8.2% and 16.4%. The major contributions to the uncertainty budget came from the calibration curves, repeatability and recovery. Tomato paste samples gathered from the supermarkets in Turkey were analysed by using the validated method. Their levels were compared both with the literature values and European Commission Regulations. 相似文献
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Hiroshi Numakura Tatsuru Watanabe Makoto Uchida Yoko Yamabe-Mitarai Eisuke Bannai 《Journal of Phase Equilibria and Diffusion》2006,27(6):638-643
The diffusion in iridium-rich Ir-Nb alloys has been studied by single-phase interdiffusion experiments. The chemical diffusion
coefficient has been measured for the primary fcc solid-solution and theL12 ordered compound Ir3Nb in the temperature range between 1650 and 1950 °C, using Ir/Ir-8Nb and Ir-26Nb/Ir-28Nb diffusion couples, respectively
(numbers indicate mol%). While the chemical diffusion coefficient in the solid-solution phase is close to the tracer self-diffusion
coefficient of pure iridium, the diffusion in the compound phase is extremely slow: the chemical diffusion coefficient is
1/40 to 1/50 of that in the solid solution. The low diffusion rate in the compound must be beneficial for high-temperature
performance of refractory superalloys based on the Ir-Nb system.
This article was presented at the Multicomponent-Multiphase Diffusion Symposium in Honor of Mysore A. Dayananda, which was
held during TMS 2006, 135th Annual Meeting and Exhibition, March 12–16, 2006, in San Antonio, TX. The symposium was organized
by Yongho Sohn of University of Central Florida, Carelyn E. Campbell of National Institute of Standards and Technology, Richard
D. Sisson, Jr., of Worcester Polytechnic Institute, and John E. Morral of Ohio State University. 相似文献
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雷姆·库哈斯策展的第十四届威尼斯建筑双年展由一个大主题”原理”和3个副主题“吸收现代性:1914年~2014年”(国家馆)、“建筑的元素”(中央展馆)和”图景宏大的意大利“(军械库展馆)构成。文章对各个主题及相应展馆进行初步介绍.同时引征库哈斯对本届建筑双年展策展的想法及思考.并附上简要解读和个人理解。 相似文献
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R. W. Vanka K. A. Harris L. M. Mohnkern A. R. Reisinger T. H. Myers N. Otsuka 《Journal of Electronic Materials》1993,22(8):1107-1112
Two material properties important to the application of HgTe/CdTe superlattices for device fabrication are band gap uniformity
and thermal stability. In this paper, we present the results of an infrared photoluminescence study of (211)B HgTe/CdTe superlattices
grown by photon-assisted molecular beam epitaxy which show that cut-off wavelength uniformity can be controlled to a level
commensurate with the demands of advanced infrared detector fabrication. Infrared photoluminescence and transmission electron
microscopy were also employed to demonstrate that (211)B HgTe/CdTe superlattices are less prone to interdiffusion than previously
believed. 相似文献