1. Investigate the uniformity of mixed gas samples

      The uniform mixing degree of standard gas will directly affect the accuracy of its component content, so the prepared standard gas must be homogenized. The prepared cylinder is placed on the rolling device and rolled for 2h to make it fully mixed. The component content changes of gas chromatography can be measured and its uniformity can be determined by means of anOVA. In addition, after the preparation of the gas standard substance is completed, it will be in a uniform state after 2h homogenization treatment. The gas standard substance has good uniformity.

2. Investigate the pressure stability of mixed gas samples

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

3. Investigate the stability of mixed gas samples 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 allowed range. Therefore, long-term stability investigation should be conducted.

Example of a cylinder for Mixture gas