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Instrumental neutron activation analysis with internal standard correction was applied for precise determine of mg quantities of Ir in high-purity IrBr4. A known amount of Au standard solution was used as an internal standard to compensate for inhomogeneity of the neutron flux through an irradiation capsule and for neutron self-shielding. The linearity of the calibration curves of Ir was improved by using an internal standard. The relative expanded uncertainty (k = 2) associated with the determined value was 0.86%, which allowed the mg quantities of iridium to be precisely determined.

FLiNaBe is a promising liquid blanket material for a fusion reactor. Since hydrogen solubility for FLiNaBe is low, one concern is the permeation of bred tritium. In order to increase effective solubility of hydrogen, the addition of Ti powder was proposed. In this study, the influence of Ti addition on the behavior of tritium generated inside FLiNaBe by neutron irradiation was investigated. The samples of FLiNaBe and FLiNaBe mixed with Ti of 5 wt% and 0.5 wt% were prepared and the solid-state samples were irradiated by thermal neutrons at Kyoto University Research Reactor. The neutron-irradiated samples were heated to 700 °C in an Ar gas flow. The released tritium was collected by a water bubbler and the temporal variation of TF and HT release was observed. Initially, the most of tritium was released as HT from both FLiNaBe with and without Ti but eventually, the most of released tritium was HT after long time heating from FLiNaBe with Ti. This result suggests that the addition of Ti can decrease the release of TF very much. The amount of tritium released from FLiNaBe with Ti was lower than that from FLiNaBe without Ti. This result suggests that the addition of Ti can suppress the release rate of tritium from FLiNaBe.

Chinese medicines and herbs have been used and are presumed safe. The concentrations of the toxics elements Cr, Co, As, Sb and Hg were analysed in Chinese medicines and herbs via instrumental neutron activation analysis. A total of 119 samples purchased from four countries with five procedures were tested. Niuhuang Jiedu Pian purchased with a doctor’s prescription in Shanghai contained As of approx 8.3 %. Additionally, approx 7.4 % of both As and Hg were found in Liushen wan. Many herbs for other Chinese medicines contained low concentrations of Hg and Co. Some chemical structures were studied via X-ray diffraction.

Instrumental neutron activation analysis with the internal standardization was applied to the precise determination of Br in polypropylene resin of candidate certified reference material. The known amount of 197Au was used as an internal standard to compensate for neutron flux inhomogeneity, to improve the γ ray measurement uncertainty and the linearity of the calibration curves. The reliability of the proposed method validated using analytical results of BCR-681. The analytical result of Br in the sample was consistent with that obtained by ID-ICPMS. The relative expanded uncertainty (k = 2) was 1.5 %, and it was equivalent to that of ID-ICPMS.