Analysis methods and performance of an automated system for measuring both concentration and enrichment of uranium in solutions.

摘要

For the 1992 INNM Meeting, we reported on an automated system under development for measuring both concentration and enrichment of uranium in solutions. In this paper, we report on measurement methods, ysis algorithms, and performance of the delivered system. The uranium concentration is measured by a transmission-corrected x-ray fluorescence method. Cobalt-57 is the fluorescing source and a combined (sup 153)Gd and (sup 57)Co source is used for the transmission measurements. Corrections are made for both the absorption of the exciting (sup 57)Co gamma rays and the excited uranium x-rays. The (sup 235)U concentration is measured by a transmission-corrected method, which employs the 185.7-keV gamma ray of (sup 235)U and a transmission source of (sup 75)Se to make corrections for the self-absorption of the (sup 235)U gamma rays in the solution samples. Both measurements employ high-resolution gamma-ray spectrometry and use the same 50-m(ell) sample contained in a custom-molded, flat-bottomed, polypropylene bottle. Both measurements are intended for uranium solutions with concentrations (ge)0.1 g U/(ell) although at higher enrichments the passive measurement will be even more sensitive.