Fig. 1
From: A non-invasive method to directly quantify surface heterogeneity of porous materials
Schematic illustration of a heterogeneous porous material. There are both internal and external interfaces, S, between the matrices and the pores accessible to the probing fluid in the heterogeneous porous material. The material has surface heterogeneity which represents the coexistence of different chemical and structural properties on the surfaces. Different colors represent matrices with different scattering length densities (SLDs), ρ(S), and the lines depict the interface, S. ρf is the SLD of probing fluid
