ABSTRACT
Following is the procedure followed for the measurements:
(i) The beads are washed with distilled water and a cleaning solutions (RBS-25), they are then dried in an oven (glass beads: 12 hours at 130◦C; PMMA beads: 24 hours at 70◦C). The dried beads are then sifted using two sieves of 315 and 400 µm pore size. Note that the cleaning removes the powder which is added to commercially available glass beads in order to prevent the formation of clusters in presence of humid atmosphere.
