【摘要】 文章涉及同时测定氡气土浓度的方法———流气延时法。该方法采用两套闪烁室测量装置和1台由50mmPVC U排水管和50mmPVC U接头制成的总体积为24L的延时装置。当氡气土混合气体以恒定流率3L·min-1流经测量系统时,延时装置后的闪烁室测量装置测定气土室中氡的参考浓度,延时装置前的闪烁测量装置经扣除气土的贡献后可测定气土室中气土的参考浓度。流气闪烁法测氡气土浓度的刻度因子的不确定度小于5.0%。更多还原

【Abstract】 One of the key techniques of building a calibrating and experimental device （thoron chamber） for thoron and it’s progenies monitors is the determination method of thoron and thoron daughters concentrations, especially in radon and thoron mixed （atmosphere.） A air-flow and time-delay method for the simultaneous measurement of （radon） and thoron reference concentrations in thoron chamber was developed in Radon Laboratory of Nanhua University. The monitoring device mainly consists of two scintillation cell measuring equipments and a time-delay equipment with the volume of 24 L. When the radon and thoron mixed gas flows through the monitoring device with the flow rate of 3 L·min^-1, the scintillation cell monitoring equipment after the time-delay （equipment） measures radon reference concentration in thoron chamber, and the another scintillation cell monitoring equipment before the time-delay equipment can measure thoron reference concentration in thoron chamber after deducting the contribution of （radon.） The uncertainties of the calibration factors of the scintillation cells for radon and thoron concentration measurement by air-flow method are less than 5.0%.更多还原