Measurement of Radon and daughter activity in air

1. 空气中氡及其子体的测量。同时测定了室内和室外空气中的氡及其子体。由于附着在墙壁、地板和天花板上的子核在空气中被移除，氡和子核之间的放射性平衡在室内空气中无法保持。另一方面，氡子体附着在气溶胶上，存在于空气中，室外氡子体的放射性比接近1。^<218>Po的附着因子为（1.3(]SY.+- - [)0.3）x10^<-3> cm^3/s，沉积速度为（1.6 ~ 5.7）x10^<-3> m/s。水中氡浓度。利用^<214>Pb的伽马射线能谱法，提出了一种测量水中氡的方法。对100毫升地下水的氡浓度进行了直接测定，氡浓度较高。对低浓度地表水的测定，采用索伦萃取法。研究发现，在位错区和花岗岩地层中均存在高浓度氡地下水。这种地层分布在广岛的东南和西北地区。

1. Measurement of radon and its daughters in air. Simultaneous measurement of radon and its daughters were performed for indoor and outdoor air. Since daoughter nuclei were removed in the air attaching to wall, floor, and ceiling, radioactive equillibrium among radon and daughters was not held in indoor air. Qn the other hand, radon daughters attach to aerosol and exist in the air, radtios of radon and daughters is nearly 1 in the out door. The attachment factor of ^<218>Po was (1.3(〕SY.+-.〔)0.3)x10^<-3> cm^3/s and the deposition velocity was (1.6-5.7)x10^<-3> m/s.2. Radon concentration in water. A method for the measurement of radon in water was developed through gamma-ray stectroscopy of ^<214>Pb. Radon cancentration was diredtly measured for the 100 cc ground water which were rather high concentration. A thoruen extraction method was applied peror to the measurement for the surface water which were low concentration. It was found that ground water with high radon concentraion existed in the dislocation area as well as the granit stratum. Such stratum distributed in south-east area and north-west areas in Hiroshima.