Fig. 2
From: Zirconia-based catalyst for the one-pot synthesis of coumarin through Pechmann reaction

FESEM images of ZrO2-TiO2 (a-c), ZrO2-ZnO (d, e), and ZrO2/cellulose (f)
From: Zirconia-based catalyst for the one-pot synthesis of coumarin through Pechmann reaction
FESEM images of ZrO2-TiO2 (a-c), ZrO2-ZnO (d, e), and ZrO2/cellulose (f)