论文部分内容阅读
在β放射性沾污监测、环境保护以及铀镭矿样分析等场合,测量对象往往是弱β放射性,或者存在强γ辐射干扰场。这都要求核辐射探测器具有很高的β/γ比,以便把弱β放射性信号从γ本底中区分开来。为此,国外在寻找合适的高β/γ比探测器,并对多种核辐射探测器的β/β比值进行了测定,但皆不太理想。我们在ST-402闪烁屏基础上制成ST-551型对-联三苯闪烁体(简称ST-551),它是将闪烁物质对-联三苯与二氯乙烷制成悬浊液,喷涂于有机玻璃衬板上热压而成。当适当改变发光体厚度时,对于~(90)Sr-~(90)Yβ源和~(60)Coγ源给出的β/γ比可达800。它为前述任务的解决提供了更为有效的探测器。
In the β radioactive contamination monitoring, environmental protection and uranium radium sample analysis and other occasions, the measurement object is often weak β radioactivity, or the presence of strong γ radiation interference field. This requires that nuclear radiation detectors have a high beta / gamma ratio in order to distinguish weak beta radioactive signals from gamma background. For this reason, foreign countries are looking for a suitable high β / γ ratio detector and measuring the β / β ratio of a variety of nuclear radiation detectors, but these are not ideal. Based on the ST-402 scintillation screen, we made the ST-551 para-terphenyl scintillator (ST-551 for short), which is made by suspending the scintillation material para-terphenyl and dichloroethane, Spray on the plexiglass liner made of hot pressing. The β / γ ratio for the ~ (90) Sr- ~ (90) Yβ source and the ~ (60) Coγ source can reach 800 when the luminophore thickness is properly changed. It provides a more effective probe for the resolution of the aforementioned tasks.