| 摘要 |
The granules take the form of substantially spherical beads with, on the one hand, in the case of a first embodiment, a mean size of between 300 and 2500 mu m and a density of 0.15 to 0.32 and, on the other hand, in the case of a second embodiment, a mean size of between 0.5 and 20 mm and a density of 0.32 to 0.5. |
