This paper reports the results obtained during an intercomparison exercise for the determination of difficult to measure radionuclides in activated reactor pressure vessel (RPV) steel samples. In total, eight laboratories participated analysing 14 C, 55 Fe and 63 Ni activity concentrations in RPV steel. In addition, some laboratories also analysed 60 Co activity concentrations. Corresponding activity concentrations were also determined using activation calculations. Robust statistical techniques were utilised for the analysis of the results according to ISO 13528 standard. The results showed good agreement for 55 Fe and 63 Ni results whereas 14 C results had significant differences. 60 Co results were in quite good agreement.

中文翻译：

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活化钢中​​难以测量的放射性核素的比对练习：放射性分析结果和活化计算的统计分析

本文报告了在确定活化反应堆压力容器 (RPV) 钢样品中难以测量的放射性核素的比对练习中获得的结果。总共有 8 个实验室参与了分析 RPV 钢中的 14 C、55 Fe 和 63 Ni 活性浓度。此外，一些实验室还分析了 60 Co 的活性浓度。还使用活化计算确定了相应的活性浓度。根据 ISO 13528 标准，使用稳健的统计技术分析结果。结果表明，55 Fe 和 63 Ni 结果具有良好的一致性，而 14 C 结果具有显着差异。60 Co 结果非常一致。