摘要
针对核材料衡算中沾污件表面核材料质量难以准确测量的问题,本文利用胶体固定法制备了不同材质、不同几何体的放射性表面沾污件,通过无源效率和有源效率校正相结合的方法测量沾污件表面铀质量,并对测量误差进行了分析。通过蒙特卡洛模拟得到探测器的探测效率,以圆柱形沾污件为基准样品确定铀自吸收校正因子,结合高纯锗探测器的测量数据,计算得到不同沾污件表面的铀质量。在590 mm的测量距离下,以石墨圆柱沾污件为基准样品确定铀自吸收校正因子时,所有沾污件表面铀质量的测量误差在20%以内,相同形状金属材质沾污件表面铀质量的测量误差均高于石墨沾污件。以不锈钢圆柱沾污件为基准样品确定铀自吸收校正因子时,金属材质沾污件表面铀质量的测量误差从小于15%减小为小于3%。
In response to the problem of difficulty in accurately measuring the surface nuclear material quality of contaminated parts in nuclear material accounting,this paper uses the colloid fixation method to prepare radioactive surface contaminated parts of different materials and geometries.The uranium mass on the surface of the contaminated parts is measured by combining passive efficiency and active efficiency correction methods,and the measurement error is analyzed.We obtained the detection efficiency of the detector through Monte Carlo simulation,determined the uranium self absorption correction factor based on cylindrical contaminated samples,and combined it with measurement data from high⁃purity germanium detectors to calculate the uranium mass on the surface of different contaminated samples.At a measurement distance of 590 mm,when using graphite cylinder contaminated samples as reference samples to determine the uranium self absorption correction factor,the measurement error of uranium mass on the surface of all contaminated samples is within 20%.The measurement error of uranium mass on the surface of metal contaminated samples with the same shape is higher than that of graphite contaminated samples.When using stainless steel cylinder contaminated parts as reference samples to determine the uranium self absorption correction factor,the measurement error of uranium mass on the surface of metal contaminated parts is reduced from less than 15%to less than 3%.
作者
刘枫飞
刘薇
李昕珂
LIU Fengfei;LIU Wei;LI Xinke(National key laboratory of particle transport and separation,Tianjing,300180,China;Research institute of physical and chemical engineering of nuclear industry,Tianjing,300180,China)
出处
《核电子学与探测技术》
北大核心
2025年第4期498-504,共7页
Nuclear Electronics & Detection Technology
关键词
伽马无损测量
沾污件
无源效率
测量误差
Gamma non⁃destructive measuremen
Contaminated parts
Passive efficiency
Measurement error
