论文部分内容阅读
本文介绍了一种测定环境空气中氚(HTO)浓度的方法。本方法以变色硅胶作为干燥剂,置于环境空气中自行吸收空气中的氚化水蒸汽,用加热蒸馏法将硅胶吸附的水蒸汽解析制备成水样品,在液体闪烁计数器上测定其氚的活性,根据采样时的温度和相对湿度估算空气中氚(HTO)的浓度。本方法的探测下限不仅与所用的液体闪烁计数器的灵敏度、本底有关,而且与环境温度和相对湿度密切相关。现场实验表明,本方法灵敏度高,简单易行,且不受样品数量限制,特别适用于较大范围内环境空气中氚浓度监测工作。
This article describes a method for the determination of tritium (HTO) concentrations in ambient air. In the method, chromotropic silica gel is used as a desiccant, and the tritiated water vapor in the air is absorbed by the ambient air by itself. The water vapor sample adsorbed by the silica gel is heated and distilled to prepare a water sample, and the tritium activity is measured on a liquid scintillation counter The concentration of tritium (HTO) in the air is estimated from the temperature and relative humidity at the time of sampling. The detection limit of this method is not only related to the sensitivity and background of the liquid scintillation counter used but also to the ambient temperature and the relative humidity. Field experiments show that this method has high sensitivity, simple and easy to operate and is not limited by the number of samples. It is especially suitable for the monitoring of tritium concentration in ambient air over a large area.