Fig. 6
From: Adsorption of copper (II) on mesoporous silica: the effect of nano-scale confinement
Intraparticle diffusion plots for the adsorption of Cu with on a SBA-15-4, b SBA-15-6, and c SBA-15-8. The section of the intraparticle diffusion model representing the external mass transfer was fit with a linear regression line based upon Piecewise Linear Regression [52]. The shaded regions represent the time break points used for the slope analysis