天然水中总α、总β放射性物质浓度很低,常需浓缩后制成样品测量源再进行放射性强度测量,而在制样中对源的厚度控制严格。因此,应先测定水样中可溶盐总量,再确定需要浓缩的水样体积。利用常规重量法测定可溶盐总量,准确度高,但操作繁琐费时。利用电导法测定,简便快速,应用也很广泛。但在许多水质标准 Natural water, total α, total β radioactive material concentration is very low, often need to be concentrated after the measurement of the sample source and then measure the intensity of radioactivity, and in the sample preparation to control the thickness of the source strict. Therefore, the total amount of soluble salts in the water sample should be determined before determining the volume of water sample to be concentrated. Determination of the total weight of soluble salts using conventional weight method, high accuracy, but tedious and time-consuming operation. Using conductivity measurement, simple and fast, the application is also very wide. But in many water quality standards