A striking mechanism for the semi-automatic operation of a cartridge firing firearm includes a receiver, a barrel attached to the receiver and providing a breach, an op rod assembly, and a bolt adapted for reciprocating movement within the receiver and engagable with the breach of the barrel and the face of a cartridge chambered therein. The movement of the upper part may both be a sliding and a tilting movement. The addition of the oil greatly enhances the aggregation potential of the hydrophobically modified particulates once placed in the well bore. It also comprises abbreviated sidewalls and bottom wall arranged to match flush against front portions of the basket’s sidewalls and bottom wall. Accordingly, the amount of current flowing in the EL element is kept constant by setting VGS to such a value as to make the current value IDS constant.