Determination of Trace Elements in High Purity Iron as a Certified Standard Material by Instrumental Neutron Analysis

摘要

Trace elements in high purity iron certified referencematerials,JSS001-4 and JSS003-4,prepared by the Iron and SteelInstitute of Japan were determined by instrumental neutronanalysis(INAA). Five or seven aliquots of each sample(ca.130～750mg) were irradiated for a short time (2 min) at a thermalneutron flux of 1.5×1012n cm-2s-1(pneumatic transfer) and fora long time (6h) at a thermal neutron flux of 3.7×10 12ncm-2s-1(cental thimble) in the Rikkyo UniversityResearch Reactor. The irradiated samples were measured byconventional γ-ray spectrometry using a coaxial Gedetector,and by anticoincidence γ-ray spectrometry with acoaxial Ge detector and a well-type NaI(Ti) detector. The lowerlimit of 7 elements (Na, Cl, V, Co, Zn, As, W) in the JSS001-4and 11 elements (Na, Al, V, Mn, Co, Ni, Cu, As, Mo, Sb, W)in theJSS003-4 were determined by these methods. The determined valueswere in good agreement with the certified and reference values.The lower limit of determination values for Sm, Ir, Au in theJSS003-4 were 0.1～1 ng/g.