摘要
为了给乏燃料后处理工艺和环境科学研究提供合适的237Np标准溶液,研制了以0.5 mol/L HNO3为介质的镎-237放射性活度标准溶液。以工厂的氧化镎作原料,经原料提纯→纯度鉴定→配成硝酸溶液→放置陈化→分装→火封→称重→均匀性检验→稳定性检验,最后进行定值。按取样规则取样品数,最小取样量为10 mg溶液,用4πα(PC)法测量,数据经方差检验法处理表明样品是均匀的。样品存放1 a,用4πα(PC)法测量和检查,证明样品是稳定的。定值是用4πα(PC)、4πα(LS)和2πα屏栅电离室等3种不同方法,经5个不同实验室测量比对,并经中国计量科学研究院检验测试后定值为:(1 702±35)Bq/g,(α=0.05)。
In order to provide a suitable 237 Np reference solution for nuclear fuel reprocessing and environmental science, a radioactivity reference solution of neptunium-237 in 0.5 mol/L HNO3 is investigated. It is prepared by dissolution of a neptunium oxide stock from plant. The preparation procedure is as following, purification and assay for purity of neptunium, preparation of neptunium nitrate solution, making solution for ageing, subpacking the solution to ampoules, fire sealing, weighing for earch ampoule, homogeneity test, stability test, and certification. According to the statistical tools, the spot-check samples from the solutions in ampoule are measured for homogeneity test by 4πα（PC）. The minimum spot-check sample size for measurement by 4πα（PC） is about 10 mg solution. The solutions in ampoule have been stored for one year, then the spot-check samples are measured for stability test by 4πα（PC）, the results prove that the solutions are stable. The certified value is measured by five different laboratories using 4rra（PC）, 4πα（LS） and 2πα grid ionization chamber, and is verified by National Institute of Metrology. The radioactivity concentration of neptunium-237 is （1 702±35） Bq/g, （α=0.05）.
出处
《核化学与放射化学》
EI
CAS
CSCD
北大核心
2005年第3期129-135,共7页
Journal of Nuclear and Radiochemistry
