The use of k 0-NAA for the determination of the n(235U)/n(238U) isotopic ratio in samples containing uranium
- Resource Type
- Article
- Authors
- Farina Arboccò, F.; Vermaercke, P.; Sneyers, L.; Soares Leal, A.; Gonçalves Bouças, J.
- Source
- Nuclear Instruments & Methods in Physics Research Section A. Oct2010, Vol. 622 Issue 2, p443-448. 6p.
- Subject
- *NUCLEAR activation analysis
*URANIUM isotopes
*CHEMICAL sample preparation
*RARE earth metals
*NUCLEAR fission
*COMPUTER software
- Language
- ISSN
- 0168-9002
Abstract: In the analysis of rare earth elements in samples containing uranium by k 0-neutron activation analysis fission of 235U was considered an undesired phenomenon until the “fission k 0-factors” were introduced to account for natural-U fission interferences. In this work, by using a reverse perspective of the problem, the observed 235U-fission and 238U activation products (along with the k 0-factors) were used to obtain information about the n(235U)/n(238U) 1 [1] Definition: n(X) refers to the isotopic abundance of isotope X isotopic ratio in the samples. The relevant formulae and data-filtering algorithm were implemented in a home-made computer software, allowing automated evaluation and selection of unbiased data. Two radioisotopes (131I and 140La) were demonstrated to be reliable candidates for n(235U)/n(238U) determination in environmental samples. The accuracy of this method was determined using several isotopic standards varying from a depleted to a highly enriched 235U content. An overall 2.31±0.03% overestimation of the isotopic ratio was observed (within 95% confidence level). [Copyright &y& Elsevier]