Fundamental and applied studies of activation analysis using the newly developed three internal standard methods

新开发的三种内标法，即稳定同位素稀释活化法、活化分析内标法和内参法，其最大的优点是加入感兴趣元素的比较标准品与样品具有相同的基质；而且，即使样品和比较标准品分别受到不同通量的粒子照射，也可以用非常简单的方程很容易地计算出感兴趣元素的绝对浓度。为了证明上述方法的有效性，本研究先后进行了几个基础实验和应用实验。(1)发展了自屏蔽效应可忽略的稳定同位素稀释活化分析方法，并应用于光子活化；(2)稳定同位素稀释法带电粒子活化分析测定生物材料中的锶；(3)内标法带电粒子活化分析同时测定铝合金中的Ti、Cr、Fe、Cu、Ga和Zr；(4)稳定同位素稀释法光子活化分析法同时测定环境材料中的Ca、Rb、Sr和Ce；(5)利用光子活化内标法对环境样品进行高精度、精密的多元素测定；(6)利用内标法对环境材料进行仪器光子活化分析。结果表明，采用上述方法可以有效地、准确地测定各种材料中感兴趣的元素。通过这些实验还表明，每种方法都是一种非常有价值的多元素激活分析技术。

The newly developed three internal standard methods, i.e., the stable isotope dilution activation analysis, the internal standard and internal reference methods for activation analysis, have the greate advantages that the comparative standard spiked with interesting elements has the same matrix as the sample, and that the absolute concentrations of the interesting elements can be evaluated easily by using very simple equations even when the sample and comparative standard are irradiated separately by particles with different flux. In order to demonstrate the usefulness of the above methods, in the present studies several fundamental and applied experiments have been tried successively as follows. (1) developement of the stable isotope dilution activation analysis in which the self-shielding effect is negligible, and its application by means of photon activation; (2) determination of strontium in biological materials by charged-particle activation analysis using the stable isotope dilution method; (3) simultaneous determination of Ti, Cr, Fe, Cu, Ga and Zr in aluminiun alloys by charged-particle activation analysis using the internal standard method; (4) simultaneous determination of Ca, Rb, Sr and Ce in environmental materials by photon activation analysis using the stable isotope dilution method; (5) highly accurate and precise multielement determination of environmental samples by means of photon activation using the internal standard method; (6) instrumental photon activation analysis of environmental materials using the internal standard method. In consequence, it was proved that the highly accurate and precise determinations of interesting elements in a wide variety of materials can be achieved effectively and favourably by using the above each method. Through these experiments, it was also suggested that each method plays an important role as a very valuable multielement technique for all sorts of activation analysis.