Performance Evaluation of Mixed Gas Standards

1. Inspection of the uniformity of the mixed gas standard sample

The degree of uniform mixing of the standard gas will directly affect the accuracy of its component content. For this reason, the prepared standard gas must be homogenized. The prepared steel cylinder was placed on the rolling device and rolled for 2 hours to make it fully mixed. The change of the component content can be measured by gas chromatography, and its uniformity can be determined by the method of variance analysis. In addition, the gas standard material is in a uniform state after 2 hours of homogenization after the preparation of the gas standard material, and the gas standard material has good uniformity.

2. Inspection of pressure stability of mixed gas standard sample

Due to the different molecular weight and boiling point of each component, the mixed gas in the cylinder will lead to stratification. After a long time of rolling, a stability test must be carried out.

3. Stability investigation of mixed gas standard sample over time

As a standard sample of mixed gas in nitrogen, it must be stable for a long time, and the content of each component changes within the allowable range.