Applicability of bremsstrahlung counting method to in-situ measurements of high level tritium.

轫致辐射计数法在高浓度氚原位测量中的适用性

基本信息

批准号：
02452291
负责人：
MATSUYAMA Masao
金额：
$ 0.9万
依托单位：
Toyama University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

项目摘要

To establish techniques for in-situ measurements of high level tritium in fuel cycles of thermonuclear fusion devices, applicability of a bremsstrahlung counting method was examined. For practical use of the bremsstrahlung counting method, it is required to allow to generate efficiently bremsstrahlung x-rays on a given material surface and to gain high transmittance in a material. From this view point, we studied the most appropriate material to generation and transmittance of the bremsstrahlung x-rays by means of theoretical analyses, and the promising material was tested by using tritium gas. Summary of main results is as follows.1. A Si-avalanche photodiode was employed as a detector of the bremsstrahlung x-rays, which acts usefully at room temperature and has characteristics such as small size and easy maintenance. The variation of intensity of the bremsstrahlung x-rays was evaluated theoretically as to various materials. As a result, it was found that the beryllium is the best use … More full material for both of generation and transmittance of the bremsstrahlung x-rays.2. Based on this result, tests by tritium gas were performed. It was seen that the counting rate of the bremsstrahlung x-rays are proportional to tritium concentration, and the detection limit was about 10^<-6>Ci/cm^3. Namely, it was revealed that it is possible to measure in-situ the amount of tritium. On the other hand, it was observed that the decrease in the counting rate was caused by an increase in total pressure even though the amount of tritium is kept constant. It was considered that the decrease is due to the self-absorption of beta-rays in a gas phase. Taking into account of the self-absorption, the observed counting rate could be reproduced within 6% by computations.3. Consequently, 1) miniaturization of the x-ray detector, 2) enhancement of detection efficiency, 3) search of the most usefull material for generation and transmittance of the bremsstrahlung x-rays. 4) high sensitivity, and 5) analysis of the pressure dependence of the counting rate wee achieved, and it was concluded that the bremsstrahlung counting method is thoroughly valid for in-situ and real-time measurements of high level tritium. Less

为了建立用于热融合设备燃料循环中高水平trip的原位测量技术，研究了Bremsstrahlung计数方法的适用性。为了实际使用Bremsstrahung计数方法，需要在给定的材料表面上有效生成Bremsstrahlung X射线，并在材料中获得高传输。从这个角度来看，我们通过理论分析研究了最合适的材料，以生成和传播Bremsstrahung X射线，并通过使用Tritium Gas测试了承诺的材料。主要结果的摘要如下1。 Si-avalanche光电二极管被用作Bremsstrahlung X射线的检测器，该X射线在室温下方便起作用，并且具有小尺寸和易于维护的特征。关于各种材料的理论，评估了Bremsstrahlung X射线强度的变化。结果，发现腹部是最好的用途……对于Bremsstrahlung X射线的发电和传播的更多材料2。基于此结果，进行了tri虫气体的测试。可以看出，Bremsstrahung X射线的计数速率与tri浓度成正比，检测极限约为10^<-6> CI/CM^3。也就是说，可以揭示有可能在原位测量tri的量。另一方面，观察到计数速率的降低是由于总压力的增加而引起的，即使tri量保持恒定。据认为，减少是由于气相中β射线的自我吸收。考虑到自我吸收，观察到的计数率可以通过计算在6％以内复制3。因此，1）X射线检测器的微型化，2）提高检测效率，3）搜索Bremsstrahlung X射线的生成和透射率最有用的材料。 4）高灵敏度和5）分析我们达到的计数速率的压力依赖性，得出的结论是，bremsstrahlung计数方法对于高水平trip的现场和实时测量非常有效。较少的