建筑材料放射性核素测量

Detecting radionuclide activity in architectural material samples

详细叙述了采用NaI低本底多道γ谱仪测量建筑材料天然放射性核素镭、钍、钾放射性比活度的原理与方法。通过测量纯镭、纯钍、纯钾标准源,计算了谱仪对镭、钍、钾的响应系数。采用逐道最小二乘法分析建材样品中镭、钍、钾放射性比活度,运用以上方法对建材样品标准源进行测量,分析结果与标准数据之差在3%之内,远低于国标对测量不确定度的要求。

This paper describes the principles of detecting the radium, thorium, potassium radioactivity in architectural material using NaI（T1） low background detector in detail. The response coefficients can be gotten by detecting pure radium, pure thorium, pure potassium standard sources, and the radioactivity of radium, thorium, potassium in architectural material samples is calculated by least squares estimation channel by channel. The standard sample which radioactivity of radium, thorium, potassium is known is detected by this detective equipment, and the difference between the analyzing result and the standard values is within 3 %,lower than the national standard for measurement uncertainty.