Scanning electron microscopy (SEM) of BHA(s) and BHA(l) and SHA(s) and SHA(l) granules. (a) Image of surface of the BHA(s) granules. (b) Higher magnification of a granule in A. (c) Image of surface of the BHA(l) granules. (d) Higher magnification of a granule in C. (e) Image of surface of the SHA(s) granules. (f) Higher magnification of a granule in E. (g) Image of surface of the SHA(l) granules. (h) Higher magnification of a granule in G.