Macroscopic heterogeneties in electroosmotic and pressure-driven flow through fixed beds at low column-to-particle diameter ratio

The existence of specific wall effects in electroosmotic and pressure-driven flows through a fixed bed at low column-to-particle diameter ration is demonstrated using dynamic NMR microscopy with 40 mu spatial resolution. The results concluded that these wall effects are very systematic along the column axis for both types of fluid flow.