Determination of trace manganese in high-purity iron by instrumental neutron activation analysis using a thermal column

Instrumental neutron activation analysis was developed to determine trace m anganese in highly purified iron. This method is based on an irradiation at a well-thermalized position in a thermal column and fast neutron interfere nce correction by extrapolating Mn-56 activities at poorly thermalized posi tions. An iron reference standard material containing 0.03 ppm Mn can be an alyzed by this method. The present method is applicable to the determinatio n of trace elements the atomic numbers of which are 1 or 2 lower than those of the matrix element.