... a) and the stress conditions (b). Conditions: PBM P6, 250 mL steel beaker, ZrO 2 -balls, ν rot = 650 min –1 , 100 mmol 1a ... d MB = 10 mm in (b). ... of Beaker Size Although a large number of organic reactions have been performed in PBMs, the influence of the beaker volume has not ...