Fig. 7
From: Nano-materials enhanced protectants for natural stone surfaces
SEM images of blank (a and e), and modified by 101S (b and f), 101S containing 0.5Â mg/mL Al2O3 nano-powder (c and g, and 1.0Â mg/mL SiO2 nano-powder (d and h) Hedishi surfaces and profiles, respectively
