液闪萃取法测量水中镭-226的分析方法研究  

Analytical method study for the determination of radium-226 in water by liquid scintillation counting

作　　者：郭琛 杨海兰[1] 杨有坤 保莉[1] 苟荣霞 王瑞俊[1] 廉冰[1] GUO Chen;YANG Hailan;YANG Youkun;BAO Li;GOU Rongxia;WANG Ruijun;LIAN Bing(China Institute for Radiation Protection,Key Laboratory of Radiation Environment&Health of the Ministry of Ecology and Environment,Taiyuan 030006)

机构地区：[1]中国辐射防护研究院国家环境保护辐射环境与健康重点实验室,太原030006

出　　处：《辐射防护》2024年第S01期41-45,共5页Radiation Protection

摘　　要：本文研究了水中镭-226的液体闪烁计数器测量方法,通过非水溶性闪烁液将镭-226的子体氡-222从水样中萃取进入闪烁液中,实现氡-222与水中其他干扰核素的分离。当镭-226与它的子体达到平衡后,通过液体闪烁计数器进行α/β甄别测量,测量氡-222、钋-218、钋-214的总α计数,间接得到水相中镭-226的活度浓度。结果表示:液闪对水中镭-226测量的淬灭很小,Quantulus 1220型液体闪烁计数器对本方法的测量本底为0.02 min^(-1),测量效率在2.52~2.60之间,探测下限小于2 mBq/L,可以满足实际环境样品中镭的测量需求。This paper studies a liquid scintillation counter measurement method for radium-226 in water.The method extracts radon-222,a daughter of radium-226,from water sample and enters into scintillation solution by means of insoluble scintillation liquid,thus realizes the separation of radon-222 from other interfering nuclides in water.After a period of time,when radium-226 and its daughter reached equilibrium,alpha/beta discrimination measurement was carried out by liquid scintillation counter to separate radon-222 and its alpha emmision daughters polonium-218 and polonium-214 from the beta emmision daughters bismuth-214 and lead-210,and indirectly obtains the activity concentration of radium-226 in the aqueous phase through the measurement of total alpha counts of radon-222,polonium-218 and polonium-214.The results indicated that the quench of liquid scintillation on the measurement of radium-226 in water is very low,and the Quantulus 1220 liquid scintillation counter has a measurement background of 0.02 cpm for this method,with a measurement efficiency of 2.52-2.60 and a minimum detection level of less than 2 mBq/L,which can meet the requirement for the measurement of radium in environmental samples.

关 键 词：液闪 镭-226 α/β甄别测量 

分 类 号：O661.1[理学—分析化学]