Flow and transport in electrochromatography Analyte retention analyte transport axial dispersion adsorption charge selectivity concentration polarization confocal laser scanning microscopy donnan exclusion electrical double layer; electrochromatography; electrohydrodynamics electrokinetic instability electroosmosis; electroosmotic flow; electroosmotic mobility electroosmotic perfusion electrophoresis hierarchical porous media hydrodynamic flow induced charge electroosmosis ion permselectivity ion permselective transport monolith nonequilibrium electrical double layer nonequilibrium electrokinetic effects nonlinear electroosmosis plate height plate number porous media pore scale dispersion refractive index matching space charge effects sphere packing quantitative imaging wall effect zeta potential