Fig. 1.

TEM images of E153 and E171. Dry particle size and morphology of E153 and E171 was determined by TEM images. (a1) and (a2) are images of E171, magnification 5800×. Three size groups of E171 particles were observed in the pictures. (b) and (c) are images of E153, magnification 5800× (b) and 44,000× (c). Two size groups of particles were observed for E153. Scale bars are 500 nm