中文摘要：

目的研究γ能谱直接测量生物干样时全能峰效率随密度的变化关系。方法对GC3018型低本底高纯锗（HPGe）γ能谱仪配备的LabSOCS软件进行实测验证后,模拟计算各参数变化对效率的影响。结果对生物干样介质测量时,HPGeγ能谱仪全能峰效率随样品盒材料的密度及样品装样密度增加而呈指数递减。结论由变化关系的拟合函数可快速对不同质量实际样品的效率差别进行校正,从而满足核事故应急情况下生物样品中γ放射性核素快速检测的需求。

英文摘要：

Objective To study the influencing factor of peak efficiency during analysis of dry powder biological samples by using gamma spectrometry.Methods Measurement of radionuclides were carried out with GC3018 low background high purity germanium（HPGe） γ spectrometer.LabSOCS software was used for simulation after validated by calibration source.Results Peak efficiency of low-background HPGe γ spectrometer decreased exponentially with the increased density of sample box and sample material.Conclusions Based on fitting functions,a correction factor of efficiency for different mass of samples can be obtained quickly.It can meet the need for rapid determination of γ-emitting radionuclides in biological samples during nuclear emergency.