EVALUATION OF EQUILIBRIUM-EQUIVALENT CONCENTRATIONS OF RADON AND THORON WITH A HIGH-SENSITIVE PASSIVE MONITOR

用高灵敏度无源监测仪评估氡气和钍气的平衡当量浓度

• 批准号: 04680231
• 负责人: MIYAKE Hiroshi
• 金额: $ 1.09万
• 依托单位: KOBE UNIVERSITY OF MERCANTILE MARINE
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04680231/
• 关键词: Radon; Thoron; Equilibrium-Equivalent; Passive Monitor; Daughter Concentration; alpha-energy Discrimination; CR-39 Track Detector; Electrostatic-Collection

Simultaneous and discriminative measurement of the concentrations of radon, thoron and their daughters was performed using a passive monitor with CR-39 track detector. Etch pits on a detector were discriminated with their sized and shapes for alpha particle energy of 6.0MeV(^<218>Po, ^<212>Bi), 7.7MeV(^<214>Po) and 8.8MeV(^<212>Po). Discriminating capability was enhanced by use of a degrader mounted on the detector. Etch pits were automatically classified for their sized and shapes using a computer-aided counting system. Radon and thoron daughters were electrostatically collected onto the degrader surface in order to eliminate alpha particles impinged from the space near the detector surface with reduced energy. A cup for electrostatic collection was designed to prevent the alpha particles emitted from daughters attached on the cup wall and to obtain a flat distribution of daughters collected on the detector surface. This method was applied to the measurement of equilibrium-equivalent concentrations of radon and thoron in thoron-rich fields.

使用带有CR-39轨道探测器的无源监视器对ra，Thoron及其女儿的浓度的同时和歧视性测量。检测器上的蚀刻凹坑用其尺寸和形状的α粒子能量为6.0mev（^<218> po，^<212> bi），7.7mev（^<214> po）和8.8mev（^<212> po）。通过使用安装在检测器上的降解器来增强区分能力。使用计算机辅助计数系统将蚀刻坑自动按大小和形状进行分类。将ra和Thoron女儿静电收集到降解器表面上，以消除从检测器表面附近的空间撞击的α颗粒，并减少了能量。设计了用于静电收集的杯子，以防止从杯墙上附着的女儿发出的α颗粒，并获得在探测器表面收集的女儿的平坦分布。该方法应用于富含索隆的田间中等效浓度的均等浓度。

项目成果

H.Miyake, K.Oda, T.Yamauchi and C.Ishibasi: "Discriminative Measurement of Radon and Thoron Concentrations wit an Electrostatic Passive Monitor" Hoshasen(Ionizing Radiation). Vol.3, No.3(in Japanese). 9-18 (1993)

H.Miyake、K.Oda、T.Yamauchi 和 C.Ishibasi：“用静电无源监测器对氡气和钍气浓度进行判别测量”Hoshasen（电离辐射）。

三宅 寛,小田啓二,山内知也,石橋千代: "静電捕集型パッシブモニターによるラドン・トロン濃度の分別測定" 放射線. 19(3). 9-18 (1993)

Hiroshi Miyake、Keiji Oda、Tomoya Yamauchi、Chiyo Ishibashi：“使用静电收集被动监测器单独测量氡气和钍气浓度”辐射 19(3)。

三宅寛,小田啓二,山内知也,石橋千代: "静電捕集型パッシブモニターによるラドン・トロン濃度の分別測定" 放射線. 19(3). 9-18 (1993)

Hiroshi Miyake、Keiji Oda、Tomoya Yamauchi、Chiyo Ishibashi：“使用静电收集被动监测器单独测量氡气和钍气浓度”辐射 19(3)。