Development of a device for the size distribution measurement of radioactive ions

1. 研制了一种测量放射性离子大小分布的装置。该装置由以下三部分组成。1)迁移率分析仪为了测量离子的迁移率分布，采用了所谓的二阶微分法。所开发的分析仪由一个格尔登吸咐器型的圆柱形冷凝器和一个带有硅半导体探测器的放射性气溶胶收集器组成。分析仪的尺寸和空气流量如下：外电极直径：12cm，内电极直径：10cm，内电极长度：第一段102cm，第二段55cm，样品空气流速：12.5 1/min，清洁空气流速：27.5 1/min。2)直流源用于扫描迁移率范围* 0.5-10 × 10^<-4>cm^2/v。本文研制了一种由稳压器、整流器和分压器组成的直流电源。3)研制了一种放射性气溶胶采集与分析装置，该装置由辊子滤波器、2个硅半导体探测器和2个脉冲光强分析仪组成。通过这种装置，可以同时测量收集在过滤器上的放射性气溶胶的生长和衰变。目前，它还有待改进，但新研制的装置被认为对测量放射性离子的大小分布具有相当精确的分辨率和测量精度。

1. A device was developed for the measurements of the size distribution of radioactive ions. The device was consisted of following three parts.1) Mobility analyzerFor measuring the mobility distribution of ions, a so-called second order differential method was adopted. The analyzer developed was consisted of a cylindrical condenser of the type of Gerdien aspirator and a radioactive aerosol collector provided with a silicon semiconductor detectors. Dimensions of the analyzer and air flow rates are as follows ; Diameter of the outer electrode : 12 cm, Diameter of the inner electrode : 10 cm, Length of inner electrode : first segment 102 cm and second segment 55 cm, Sample air flow rate : 12.5 1/min and Clean air flow rate : 27.5 1/min.2) D.C sourceFor scanning the mobility range * 0.5-10 x 10^<-4>cm^2/v.sec, a D.C source which consists of a stabilizer, a rectifier and a potential divider was developed.3) A device for the collection and analysis of the radioactive aerosolsA device consisted of roll filter, two silicon semiconductor detectors, and two pulse hight analyzers was developed. By this device, simultaneous measurements of growth and decay of the radioactive aerosols collected on the filter are possible.2. At the present time, it leaves something to be desired, but the device developed and newly constructed is thought to be useful to measure the size distribution of radioactive ions with fairly accurate resolution and measuring accuracy.