Reactant Concentration for No Pore Diffusion refers to the amount of reactant present at any given point of time during the process, in Catalyst Deactivation. And is denoted by CA,NP. Reactant Concentration for No Pore Diffusion is usually measured using the Mole per Cubic Meter for Molar Concentration. Note that the value of Reactant Concentration for No Pore Diffusion is always positive.