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 manganese in highly purified iron. This method is based on an irradiation at a well-thermalized position in a thermal column and fast neutron interference correction by extrapolating56Mn activities at poorly thermalized positions. An iron reference standard material containing 0.03 ppm Mn can be analyzed by this method. The present method is applicable to the determination of trace elements the atomic numbers of which are 1 or 2 lower than those of the matrix element.