^(235)U/^(231)Pa质谱法测铀年龄  

Determination of Uranium Age by Measuring ^(235)U/^(231)Pa With Mass Spectrometry

作　　者：黄声慧 常利[1] 陈彦[1] 赵立飞[1] 朱留超[1] 赵兴红[1] 赵永刚[1] 

机构地区：[1]中国原子能科学研究院放射化学研究所,北京102413

出　　处：《核化学与放射化学》2017年第5期368-372,共5页Journal of Nuclear and Radiochemistry

摘　　要：建立了同位素稀释-多接收电感耦合等离子体质谱法测^(235)U/^(231)Pa原子比得到高浓铀年龄的方法。经过两次TTA萃取-反萃后从母体237 Np中分离得到233Pa稀释剂,Pa中去Np的去污因子均在200以上。在用标准物质CRM U900对233Pa稀释剂的浓度进行标定后,分别以233 U、233 Pa作为^(235)U、231 Pa的稀释剂,质谱测得^(235)U/^(231)Pa原子比计算高浓铀年龄,采用该法对标准物质CRM U850进行年龄测量,其结果与参考值的相对偏差为1.97%。该法可用于核法证与核保障监督中的高浓铀年龄测定。Isotope dilution combining with multi-collector inductively coupled plasma mass spectrometry through measuring ^235U/^231Pa to determine the age of high enriched uranium（HEU）was studied.The spike of ^233Pa was separated from237 Np after twice TTA extraction and back-extraction.The decontamination factor（DF）（Np）in ^233Pa exceeds 200.The concentration of 235 U and 231 Pa was measured by isotope dilution mass spectrometry using spike of ^233U and ^233Pa which calibrated in-house by the reference material CRM U900,respectively.So the ratio of ^235U and ^231Pa can be calculated,and HEU age can be obtained.The method was used to determine the age of the reference material CRM U850,and the relative error of results are 1.97%.The method can be used to measure HEU age in nuclear forensics and nuclear safeguard.

关 键 词：铀年龄 核取证 质谱 离子交换法 

分 类 号：TL271.8[核科学技术—核燃料循环与材料] TL274