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原子吸收光谱法测定拉伸断口铬镍钼钛钢样品中主成分 总被引:4,自引:0,他引:4
研究了毫克级铬镍钼风样品中主成分镍的火焰原子吸收光谱法(FAAS法)和铬、钼、钒、钛、铝的塞曼恒温平台石墨炉原子吸收光谱法(ZSTPF-AAS法)。采用了微波溶样技术作为防污染样品预处理技术,采用石墨管硅涂层改进技术提高了仪器的测试精度。其中铬、镍、钼、钒、钛、铝的相对标准偏差分别为2.7%,0.97%,8.6%,7.3%,1.7%,7.3%。其加标回收率分别为96.5%,97%,96.7%,93%,98%,91%。通过分析,发现在较低温度下铬镍钼钛钢断面上有轻微的钼偏析现象,可能是拉伸断裂的主要化学影响因素。 相似文献
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Influence of relaxation effects on probabilities of the 2s2p35S2-2s22p2 3P1,2 intercombination transitions in NII 下载免费PDF全文
Transition probabilities of the 2s2p^3 {}^5S_2-2s^22p^2 {}^3P_{1,2} intercombination transitions in NII have been calculated by using a large-scale multiconfiguration Dirac-Fock method. In the calculation the most important effects of relativity, correlation, and relaxation are considered. From the calculated transition probabilities, the lifetime of the 2s2p^3 {}^5S_2 metastable state is derived. The result is in excellent agreement with the latest experimental result. In the meantime the influence of anomalously strong relaxation effects on probabilities of the 2s2p^3 {}^5S_2-2s^22p^2 {}^3P_{1,2} lines in NII have been found. 相似文献
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开放式微波消解与干灰化法消解测量食品中铅的方法比较 总被引:1,自引:0,他引:1
对开放式微波消解法与干灰化法消解测量食品中铅的方法进行了比较,试验表明,前者操作简易,试验周期短,在测量精度和加标回收率方面两种方法无显著性差别。 相似文献
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This work described methodology of Sn, Pb, Cd and Zn impurities determination in high-purity graphite at direct atomic absorption spectrometry (AAS) with flame furnace (FF) atomizer. It was evidence that quality of AAS measurements are depended from sample amount, its homogeneity, particle size, as well as calibration procedure and operation parameters of FF atomizer. Prior to analysis the method has been developed and optimized with respect to the furnace heating temperature and flame composition of FF atomizer. Conditions of absorption peak areas (QA) formation to each element were studied on the basis of contribution into its value some of individual parameters of analytes, including mass-transporting process from increasing mass of graphite samples into gas phase. Because particle size and homogeneous distribution of analyte in powdered materials has an enormous influence on accuracy and precision of measurement results, graphite as well as appropriate series of powdered reference standards was previously ground and investigated. Graphite samples to be analyzed and standard reference materials with mass from 0.025 to 0.200 g was previously briquetted as pellet and insert on corresponding hole in furnace. The characteristic mass (g0) of Sn, Pb, Cd and Zn were 0.35, 0.1, 0.008 and 0.025 ng, respectively, and relative standard deviation (Sr) not more than 20%. 相似文献
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Sirilak Sattayasamitsathit Panote Thavarungkul Proespichaya Kanatharana 《Electroanalysis》2007,19(4):502-505
A bismuth film was prepared on glassy carbon electrode (GCE) and used in a flow injection amperometric system to analyze tetracycline. Bismuth film electrode (BiFE) preparation and flow injection amperometric parameters were optimized. System performances of BiFE were compared to GCE. BiFE was validated with three different lots of real sample, 250 mg tetracycline capsules, the results showed good agreement, i.e., between 240 and 260 mg per capsule. Good relative recoveries were also obtained in the range of 86–106%. 相似文献
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文章报道用铂作基体改进剂直接测定全血中铅的石墨炉原子吸收光谱法。同时应用衬钽技术,大大延长了石墨管的使用寿命。该方法准确、简便快速,灵敏度为1.74μg·L~(-1),回收率为96%~103%,变异系数小于5%。 相似文献