Liquid flow modulation Chemical reactors 16 Modulation 10 Trickle bed reactor 10 Catalysts 8 Liquids 8 Periodic operation 8 Trickle bed reactors 8 Liquid hold ups 6 trickle bed reactor 6 Axial positions 4 Catalytic oxidation 4 Ethanol 4 Hydrodynamics 4 Liquid flow rates 4 Mathematical models 4 Oxidation 4 Oxygen 4 Palladium 4 Porous materials 4 Solutions 4 Trickle-bed reactors 4 liquid flow 4 Acetic acid 2 Acetic acid productions 2 Alcohol oxidation 2 Alcohols 2 Aldehydes 2 Approximation theory 2 Aqueous ethanol solutions 2