SysML1.0:

'B.4.8.3 Activity Diagram (EFFBD) - Acceleration (detail)
Figure B.35 shows the ProvidePower activity, using the decomposed activities and objectFlows from Figure B.34. It also uses AllocateActivityPartitions and an allocation callout to explicitly allocate activities and an object flow to parts in the PowerSubsystem block.'

In fact the AllocateActivityPartitions in Figure B.35 represent blocks, not part Properties typed by blocks.