1C-O2-1740 PDF
極微量アクチノイドを利用した環境科学研究
Various anthropogenic radioisotopes in the surface environment have been used over the last decades as tracers in studies for environmental dynamics. According to their specific environmental behaviour, their different half-lives and input sources, radionuclides have found a large range of applications. Due to recent improvements in instrumentation and chemical pretreatments, ultra-trace long-lived actinides are becoming to be measured easily using Accelerator Mass Spectrometry (AMS).
Actinides are situated immediately under the Lanthanides in the periodic table, but unlike Lanthanides, they have a large variety of chemical states in the surface environment. This means, they have different chemical valences and species in the environment, and exhibit different behaviours. Furthermore, each element has some isotopes, which have different half-life, and their isotopic compositions are largely different depending on their origin. Thus, if one has a good understanding of their features in the target systems, one will be able to use them as strong tools in the environmental/geochemical studies. In this presentation, we would like to introduce some studies which using/measuring actinides in the environment.