Singh N P, Wrenn M E
Radiobiology Division, University of Utah, School of Medicine, Salt Lake City 84112.
Sci Total Environ. 1988 Mar;70:187-203. doi: 10.1016/0048-9697(88)90259-8.
This paper summarises the radiochemical procedures utilised in our laboratory to determine U, Th and Pu in different sample matrices, including soft tissues, bones, urine, faeces, soil, water, air-filters, lichen, and building materials such as granite, phosphate and concrete. Sample preparation, depending upon the matrix of the sample, includes either dry ashing and/or wet ashing with a mixture of HNO3 and H2SO4 or HNO3 alone with occasional additions of a few drops of HNO3 and H2O2. Uranium, Th and Pu are either co-precipitated with Fe carrier as hydroxides or with Ca as oxalates. Solvent extractions are performed from 2M HNO3, 4M HNO3 or 10M HCl depending upon the actinide or combination of actinides to be determined. The techniques have been very successful for most samples, with radiochemical recoveries exceeding 70%. However, radiochemical recoveries of Th from soil samples have been very poor (10-30%). Attempts are being made to improve these recoveries.
本文总结了我们实验室用于测定不同样品基质（包括软组织、骨骼、尿液、粪便、土壤、水、空气过滤器、地衣以及花岗岩、磷酸盐和混凝土等建筑材料）中铀、钍和钚的放射化学程序。根据样品基质的不同，样品制备包括干式灰化和/或用硝酸和硫酸的混合物或单独用硝酸进行湿式灰化，偶尔添加几滴硝酸和过氧化氢。铀、钍和钚要么与铁载体作为氢氧化物共沉淀，要么与钙作为草酸盐共沉淀。根据要测定的锕系元素或锕系元素组合，从2M硝酸、4M硝酸或10M盐酸中进行溶剂萃取。这些技术对大多数样品都非常成功，放射化学回收率超过70%。然而，土壤样品中钍的放射化学回收率非常低（10%-30%）。目前正在努力提高这些回收率。
