Effects of hydration on elemental sensitivities in neutron activation analysis using prompt and delayed gamma rays

A 1.85 x 1011 Bq (5Ci) Am/Be neutron source is being used to investigate the feasibility of applying the absolute method in the elemental analysis of bulk samples by instrumental neutron activation making use of prompt and delayed gamma rays. Among the different factors which might contribute to variations in sensitivity or in the uncertainty associated with the elemental concentration is the presence of hydrogen in the sample. It is the purpose of this study to examine whether the presence of water in bulk samples such as landfill waste produces significant variations in measured elemental concentrations and if so, requires samples to be dried, which can be a time consuming and expensive process. The effect of hydration of samples on the sensitivity of ten elements has therefore been investigated. Samples with different water concentrations in a fixed volume and shape were prepared and used in the analysis in order to obtain a measure and an understanding of the effects involved. (author) 14 refs,; 7 figs