| In high performance liquid chromatography (HPLC), the increasing in the solute resolution is one of the most important hot points in theoretical and applied researches. The behavior of solute retention relates to both of thermodynamic and dynamic factors, but scientists have played much more attention to the former. The investigation of the quantitative relationship among all kinds of dynamic factors also have important to make the best solute resolution in HPLC. This thesis only concerns with the contribution of the flow rate and composition of mobile phase to the separation efficiency of solute. It includes three parts as follow:1. Review: In this chapter, the recent development of dynamics and the velocity theory in chromatography were briefly introduced. The factors effecting on the band expanding including the quantitative relationship between the half-peak width and retention time, the fundamental theory of LC—stoichiometric displacement theory for retention (SDT-R), short column theory, and convergence of solute retention were also briefly introduced.2. The factors effecting on the resolution of small solutes and the convergency of dynamic factors: Based on random walk model, a linear relationship between half-peak width and the square root of retention time was theoretically derived and the dynamic convergence was found to exist also. In the experiment, we verified:1) A good linear relationship between half-peak width and the square root of retention time at different methanol concentration in mobile phase under a fixed flow-rate exists. This linear relationship between the retention time and half-peak width reported in literature was also experimentally proved to exist. However, the difference between the both linear equations is that the obtained two slopes have a quite different character. With experimental test for small solutes, benzene, toluene, naphthalene, and biphenyl, the obtained result indicates that for the former, a convergent point exists from the plot of the obtained slope versus the molecular structural parameters of the solute, such as van der waals volume or van der waals area, but not from the latter. In addition, a good coincidence between the experimental result and the expected coordinate of the convergence indicates that the linear relationship between half-peak width and the square root of retention time really reflects the intrinsic relations of dynamic factor for the band expanding of small solute.2) Also, a good linear relationship between half-peak width and the square root of retention time at different flow rate of mobile phase under a fixed methanol concentration exist. The foregoing two kinds of convergences were found to exist also. However, the magnitude of the two coordinates are different, the reason for explaining this fact will be investigated further.3. The dynamic factors for the separation of proteins in HPHIC: Using three column lengths 3.0, 5.0 and 10.0cm of hydrophobic interaction liquid chromatographic(HPHIC) column, seven kinds of standard proteins, Cytochrome C, Myoglobin, Ribonuclease, Lysozyme,α-Chymotrypsin,α-Amylase, and Insulin were separated under different flow rates of mobile phase, the relations among flow rate, column length, column pressure and resolution were investigated. It was found that the separation efficiency of biopolymers is almost independent of column length and mobile phase flow rate, proteins could be completely separated by using in short column of 3.0cm, it was explained with SDT-R and short column theory. In the separation and analysis of protein, the short column have many advantages, it would be expected that it may also be employed in large-scale manufacture in the future.
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