Radon‐in‐air monitor (RAD7, Durridge Co.) has been widely used to measure ²²²Rn in water samples. RAD7 measures ²²²Rn via ²¹⁸Po⁺ (t_1/2 = 3.1 min), which is electrically attracted to a silicon alpha detector. In this study, a new method was developed for measuring ²²²Rn in water samples by modifying a commercially available pulsed ionization chamber (PIC, FT‐Lab Co.). The PIC detects and amplifies the electric pulses generated by microspace charges produced by ²²²Rn decay. Two passive PICs (volume: 2 × 400 mL) were combined and modified to form an active system (named Rn‐SNU) that continuously circulates air (~ 1 L min⁻¹). Rn‐SNU is approximately seven to nine times more efficient than RAD7 and does not necessitate a delay of ~ 15 min to reach radioactive equilibrium between ²²²Rn and ²¹⁸Po⁺. However, RAD7 is more accurate in discriminating ²²²Rn daughters, ²¹⁸Po⁺ and ²¹⁴Po⁺. In this study, ²²²Rn was successfully measured in coastal seawater samples using Rn‐SNU connected to a grab bottle. Our results suggest that ²²²Rn measurements in water samples can be conducted more efficiently and rapidly with an Rn‐SNU than with other widely used instruments and methods.

中文翻译：

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使用脉冲电离室快速准确地测量水中的don

in气监测仪（RAD7，Durridge公司）已被广泛用于测量水中的²²² Rn。RAD7通过²¹⁸ Po ⁺（t _1/2 = 3.1分钟）测量²²² Rn ，该电被电吸引到硅α探测器。在这项研究中，通过修改市售的脉冲电离室（PIC，FT-Lab Co.），开发了一种用于测量水中样品中²²² Rn的新方法。PIC检测并放大由²²² Rn衰减产生的微空间电荷产生的电脉冲。合并并修改了两个无源PIC（体积：2×400 mL），形成了一个有源系统（命名为Rn-SNU），该系统使空气连续循环（〜1 L min ^-1）。Rn-SNU的效率大约是RAD7的7至9倍，并且无需延迟〜15分钟即可达到²²² Rn和²¹⁸ Po ⁺之间的放射性平衡。但是，RAD7在区分^222个Rn子代，²¹⁸ Po ⁺和²¹⁴ Po ^+时更为准确。在这项研究中，使用连接到抓瓶的Rn-SNU成功测量了沿海海水样品中的²²² Rn。我们的结果表明，与其他广泛使用的仪器和方法相比，使用Rn-SNU可以更高效，更快速地进行^222种水样品中的Rn测量。