Determination of trace-elements in certified reference materials of high-purity aluminum by instrumental neutron-activation analysis

Abstract

Multi-elements in JAC0021, JAC0022 and JAC0023 certified reference materials of high-purity aluminum prepared by the Japan Society for Analytical Chemistry (JSAC) were determined by instrumental neutron-activation analysis (INAA). Four or five aliquots of each sample (ca. 27∼1018 mg) and comparative standards were irradiated for a short time (10 s) at a thermal neutron flux of 1.5×10¹² n cm⁻² s⁻¹ (pneumatic transfer) and for a long time (6 h) at a thermal neutron flux of 3.7×10¹² n cm⁻² s⁻¹ (central thimble) in the Rikkyo University Research Reactor (TRIGA Mark-II, 100 kW). The irradiated samples were measured by conventional γ-ray spectrometry using a coaxial Ge detector, and by anti-coincidence and coincidence γ-ray spectrometry with a coaxial Ge detector and a well-type NaI(Tl) detector. The concentrations of 21 elements in JAC0021, 20 elements in JAC0022 and 11 elements in JAC0023 were determined by these methods.