Advantages of low-background liquid scintillation alpha-spectrometry and pulse shape analysis in measuring 222Rn, uranium and 226Ra in groundwater samples
Advantages of low-background liquid scintillation alpha-spectrometry and pulse shape analysis in measuring 222Rn, uranium and 226Ra in groundwater samples
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DOI：
10.1007/bf02063626
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发表时间：
1997-12-01
影响因子：
1.6
通讯作者：
Hukkanen, H
中科院分区：
文献类型：
--
作者：
Salonen, L;Hukkanen, H
用液体闪烁计数法(LSC)和脉冲波形分析法(PSA)测量了地下水中的氡和总α、β活度。我们使用常规的LSC计数器测量水中的氡，但使用低本底LSC光谱仪测量总活度。用常规计数器计数60min，水中氡的检测下限为0.6Bq/L，而用两种配备脉冲波形分析仪的低本底LSC光谱仪，检测下限分别为0.1Bq/L和0.2Bq/L。用一种简单的样品制备方法、低本底的PSA和光谱分析测量了总的α和β活度。对于180分钟的计数和38毫升的样品体积，用两台光谱仪记录的总α和β的LLD分别为0.02和0.03Bq/L和0.2和0.4Bq/L。该方法还可以计算水中的铀和(226)Ra含量，并表明存在其他一些长寿命的放射性核素((210)Pb、(228)Ra或(40)K)。U和(226)Ra的LLD分别为0.02Bq(-1)和0.01Bq·l(-1)。用这种LSC方法获得的LLD比U和(226)Ra的最大允许浓度低两个数量级。
Liquid scintillation counting (LSC) and pulse shape analysis (PSA) was used in measuring radon and gross alpha-and beta-activities in groundwater. We used conventional LSC counters for the measurement of radon in water, but low-background LSC spectrometers for the gross activity measurements. The lower limit of detection (LLD) for radon in water is 0.6 Bq/l for a 60 min count with a conventional counter, but 0.1 or 0.2 Bq/l, with the two types of low-background LSC spectrometers equipped with a pulse shape analyser (PSA). The gross alpha and beta activity measurements are made using a simple sample preparation method, PSA of a low background LSC and spectrum analysis. The LLD recorded for gross alpha and beta with the two spectrometers are 0.02 and 0.03 Bq/l and 0.2 and 0.4 Bq/l, respectively, for a 180 minutes count and a 38 ml sample volume. The method also enable the calculation of the U and (226)Ra contents in water and indicates the presence of some other long-lived radionuclides, ((210)Pb, (228)Ra or (40)K). The LLD for U recorded with both spectrometers is 0.02 Bq(-1) and for (226)Ra 0.01 Bq.l(-1). The LLDs attained by this LSC method are two orders of magnitude lower than the maximum permissible concentrations set for U and (226)Ra.