利用手持式γ核素识别仪快速检测石材中γ放射性核素含量

提出一种利用手持式γ核素识别仪快速测量石材中天然放射性核素含量的方法。该方法借助低本底HPGe γ谱仪,运用能谱分析法确定手持式核素识别仪对226Ra、232Th、40K含量的刻度系数参考值;然后使用手持式γ核素识别仪测量石材中放射性核素γ能谱,利用经过刻度系数参考值修正后的测量结果,估算出石材中226Ra、232Th、40K的比活度。结果表明:该方法测量结果与低本底HPGe γ能谱仪分析结果的最大偏差为25.1%(CRa)、-27.2%(CTh)、-15.2%(CK),可适用于快速无损的检测石材样品γ放射性比活度,以及快速估算装饰石材所致的外照射剂量。

Rapid Detection of Radioactive Content in Stone by Hand-held γ Radioisotope Identification Device

A rapid measurement method using a handheld gamma radionuclide recogniser to rapidly measure the content of natural radionuclides in stone was proposed. The reference values of the calibration coefficients of 226Ra, 232Th and 40K in the handheld radionuclide recogniser were determined by means of the energy spectrum analysis method of the low background HPGe γ spectrometer. Then the radionuclide gamma spectrum in the stone was measured by the handheld radioisotope identification device (RID). The specific activity of 226Ra, 232Th and 40K in stone was estimated according to the calibration coefficient. The results showed that the maximum deviations between the proposed method and the low background HPGe gamma spectrometer were 25.1%(CRa), -27.2%(CTh), -15.2%(CK) respectively. The proposed method can be applied to the rapid and nondestructive detection of specific activity of gamma radiation in stone samples and the rapid estimation of external radiation dose caused by decorative stone.