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1. With the design of bell shaped cylinder head, the sample distribution is more uniform, the sample loading amount can be increased, and the resolution efficiency can be improved;

2. The bellmouth column head can prevent the high-speed flow from damaging the column bed;

3. The stainless steel jacket of the inner glass lined tube of the upper sample column replaces the traditional quantitative ring of the flow injection valve, which is conducive to the preparation of high concentration samples and thorough elimination

4. In addition to the phenomenon of high concentration sample blocking the valve interface;

5. Flange column is easy to disassemble and clean;