Determination of naturalα-radionuclides related to millisecond order lives in environmental samples using the time interval analysis (TIA) method
Determination of naturalα-radionuclides related to millisecond order lives in environmental samples using the time interval analysis (TIA) method
复制标题
使用时间间隔分析 (TIA) 方法测定环境样品中与毫秒级寿命相关的天然 α-放射性核素
DOI：
10.1007/bf02040224
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发表时间：
1995
影响因子：
1.6
通讯作者：
N. Fukuyama
中科院分区：
文献类型：
--
作者：
T. Hashimoto;F. Ishizuka;Y. Yoneyama;T. Kubota;N. Fukuyama
利用多时间间隔分析（TIA-MTA）技术，从理论和实验的角度，对放射性衰变事件的时间文件进行了分析，以毫秒为单位，选择性地提取了216po （145 ms，钍系列）、217At （32.3 ms，镎系列）和215po （1.78 ms，锕系列）在各自的前母元素衰变后的连续α衰变脉冲事件。在理论处理中，将自然衰减序列中每个相关事件的检测灵敏度与更广义的条件进行比较。值得注意的是，评估的检测灵敏度随半衰期的缩短而成比例地增加，顺序如下：214Po>215Po>217At>216Po。最后，将TIA应用于日本秋田多川温泉中钍系不平衡状态的澄清。224ra在上游和下游的活性分别为3.41±0.38和0.60±0.08 Bq/l。镭钍同位素活度比结果表明，与钍同位素相比，镭同位素优先沉淀，反映了下游强酸性温泉水对酸度降低的敏感性。
The time files due to radioactive decay events were analyzed for the selective extraction of successive alpha-decay pulse events in millisecond orders, such as216Po (145 ms, thorium series),217At (32.3 ms, neptunium series), and215Po (1.78 ms, actinium series) after respective preceding parents decay, using a multiple time interval analysis (TIA-MTA) technique from both theoretical and experimental viewpoints. In the theoretical treatments, the detection sensitivities of each correlated event in natural decay series was compared with more generalized conditions. It was noteworthy that the evaluated detection sensitivity had increased proportionally with shorter half-lives in the following order:214Po>215Po>217At>216Po.Finally, the present TIA was applied to the clarification of thorium series disequilibrium states in Tamagawa (Akita, Japan) Hot Spring waters. Activities of224Ra were evaluated to be 3.41±0.38 and 0.60±0.08 Bq/l at the upper and lower stream, respectively. The results from activity ratios of radium to thorium isotopes showed a preferential precipitation of radium isotopes in comparison with thorium, reflecting the sensitivity to the lowering acidity of strongly acidic hot spring waters in the lower end of the stream.