Barinova N. Nonlinear electrophoresis and electroosmosis for single particles and complex systems

The thesis is devoted to the study of regularities of electrophoresis for particles of different nature and electroosmosis near the surface of individual particles and in system containing different components. The electrophoresis velocities of conductive and non-conductive particles as a function of the applied voltage and the dispersion medium were experimentally measured and theoretically calculated; the dependence of the nonlinear component of the electrophoresis velocity of the Peclet number was experimentally confirmed.The velocities of electroosmotic flow near conductive particles with a curved surface and a selective conductivity were measured. The profiles of electroosmotic flow for the individual ion-exchange and metal particles were compared. In both cases the theoretically predicted quadratic dependence of the electroosmosis velocities on electric field strength was confirmed. The velocity of electroosmosis in the chains of ion-exchange beads was investigated. The decrease of flow velocity at the end of the chain was detected. The study of voltage drop across different sections of the system was conducted; the dependence of the concentration polarization on the location of the granules and its influence on the velocity of the electroosmotic flow was analyzed. The vortex flow in the system consisting of different granules, which provides fluid mixing, was obtained.Polarization processes and electroosmosis velocity in the complex system ion-exchange membranes / porous glass diaphragm / ion-exchange granules depending on its arranging were investigated. It is shown that the highest degree of polarization and the maximum quasistationary electroosmosis velocity are observed in the case when the ion-exchange granules are located near the diaphragm on the cathode side.