(a)
(b)
(c)
(d)
Figure 4: Contour maps of and ratios of the FASF sample and representative pore shapes in areas 1~3: (a) micropore volume ≥ 10−2 mm3, (b) micropore volume  mm3, (c) micropore volume  mm3, and (d) micropore volume < 10−4 mm3.