采用NaI(Tl)γ谱仪对含铀矿体的直接铀定量方法  

A Method for Determining Uranium Content Directly for Uranium-bearing Ore-body Using NaI(Tl) Gamma Radiation Spectrometer

作　　者：吴永鹏[1,2,3] 汤彬[2,3] 程建平[1] 王哲[3] 梁永顺[3] 

机构地区：[1]清华大学工程物理系,北京100084 [2]东华理工大学,南昌330013 [3]核技术应用教育部工程研究中心(东华理工大学),南昌330013

出　　处：《核电子学与探测技术》2011年第12期1394-1398,共5页Nuclear Electronics & Detection Technology

基　　金：国家自然科学基金项目"铀矿能谱型核测井全谱解析的核素含量定量解释方法研究"(41074078)

摘　　要：目前,采用NaI(Tl)探测器的铀矿γ总量测井不能直接获得铀含量,地面γ能谱测量可以直接得到镭组核素含量,在铀-镭不平衡的情况下并不能当作铀含量。NaI(Tl)谱仪不能获得含铀矿体的精细γ谱,其仪器谱也反映不出与铀含量直接相关的特征峰,采用NaI(Tl)探测器的γ能谱测量是否能直接获得铀含量,至今尚无研究。采用CR-320型便携式NaI(Tl)闪烁谱仪对系列含铀硬岩体模型进行测量,通过234mPa之1.001 MeV特征能量窗,并结合线性回归相对分析法直接计算铀含量,获得了良好应用效果,含铀500 ppm以上相对误差不超过10.0%,对其它主要核素定量误差低于9.5%。Currently,NaI（Tl） detector is widely used for detecting natural gamma radiation in exploration of uranium mine.Gross gamma logging tool measures total gamma radiation which are from daughter products mainly,and ground gamma radiation spectrometer measures their spectra and determines the content of radionuclide in radium group directly,which are not directly related to the in-situ uranium content.NaI（Tl） scintillation spectrometer can＇t measure the fine structure of gamma spectrum from uranium-bearing ore-body,and the spectrum measured don＇t show the characteristic peaks which are directly related to uranium content.Under these circumstances,there is no any study and report yet whether using NaI（Tl） gamma radiation spectrometer can determine uranium content directly.The present work measures a series of hard rock radionuclide-bearing ore-body using CR-320 model portable NaI（Tl） spectrometer,determines uranium contents directly by using linear regression relative analysis based on 234mPa,1.001 MeV characteristic energy window,and gets good results.The relative error of uranium content over 500 ppm is less than 10.0%,and the error of main radionuclide content is less than 9.5%.

关 键 词：含铀矿体 直接铀定量 NaI(Tl)γ谱仪 能量窗分析 

分 类 号：TL81[核科学技术—核技术及应用]