Determination of uranium in iron by alpha-ray spectrometry

In order to determinate uranium in iron by alpha-ray spectrometry, methods of separating only uranium nuclides from iron were investigated. Dissolved iron solutions added 11.3 μg uranium and/or 33.3 μg thorium solution were used in this work. For determination of radioactivity of reduced to tetravalent uranium nuclides, 147Sm as an internal standard was added in the solution. And, thorium nuclides interfering in an alpha-spectrometry were removed by an anion-exchange chromatography. Uranium nuclides in coprecipitated samples were measured by an alpha-spectrometer with a surface barrier type Si detector. As a results, recovery of uranium nuclides was obtained with 95 - 100%. And we found ppb level uranium in iron was able to be determined by the alpha-spectrometry. (author)