How do you review instrument analysis?
Surface chemical inertness, that is, the surface has no adsorption or poor adsorption, and can not react with the substance under test
The porosity, surface area, contact area of the liquid sample and fixed larger. (3) high thermal stability, mechanical strength, not easy broken. (4) the carrier size requirements, should be uniform and fine, which helps to improve the efficiency of the column. But the small particle will lead to lower column pressure, which is not good for operation. Generally choose 40-60 items, 60-80 items and 80-100 items.
Requirements for fixed fluids:(1) low volatility, lower vapor pressure under operating conditions to avoid loss(2) good thermal stability, no decomposition under operating conditions, and liquid at operating temperature(3) each component of the sample has the proper dissolving capacity, otherwise, the sample is easy to be taken away by carrier gas and can not be allocated(4) high selectivity, i.e., the highest possible separation capacity for different substances with the same boiling point or similarity(5) the chemical stability is good, and does not react with the substance under test
