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近10年来,由于微量分析的需要迅速增加,灵敏度高选择性强的荧光分析法日益受到重视。有关文献数量猛增,内容也从一般仪器及分析方法介绍发展到高精度、高灵敏度、自动化、多用途的新仪器新技术研究。荧光分析对象从以无机样品为主发展到以有机及生化样品为主,并从成分分析向化学结构、化学形式、微观分析、空间分布等状态分析发展,应用遍及各个领域。荧光光谱图册也陆续出版,美国费城Sadtler研究实验室自1974年起出版标准荧光光谱图及各专用荧光光谱图(如药物)。荧光分析法的应用范围与发射光谱法、火焰光度法、质谱法等相仿,成为一种重要的仪器分析方法。 相似文献
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氮在自然界中有两种稳定性同位素,~(14)N(99.635%)和~(15)N(0.365%)。由于同位素~(15)N具有非放射性的特点,已被广泛用作标记原子,进行农业、土壤、生物、医学等过程研究。在各种同位素~(15)N分析方法中,光谱法由于仪器简单,操作方便,灵敏度和准确度较高,已成为一种广泛应用的重要方法,并生产了专门分析仪器。 相似文献
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The surface morphology,crystallite size distribution, and the surface and depth analyses for the coneentratons of impurity elements and cobalt oxide ions of several samples of Co_3O_4 catalyst for ammonia oxidation, which were obtained under various conditions for preparation, calination,usage,and regeneration, were observed by means of a transmission electron microscopy(TEM), a scanning electron microscopy(SEM),and an ion microprobe mass analyzer (IMMA). The observed results are discussed in relating with the experimental activity of the catalyt. It is concluded that the possible causes of the decline in the activity of the catalyst are that the impurity elements transport from the bulk phase and enrich onto the surface and the cobalt oxide ions on the surface decrease when the catalyst has been used at the high temperature for a long time. 相似文献
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