exposing {HEAD ~ said coal} within said coking chamber to {TAIL ~ microwave radiation} only, and thereby forming said coal into hot coke; and 
to
exposing { HEAD ~ said coal } within said coking chamber to { TAIL ~ microwave radiation } only , and thereby forming said coal into hot coke ; and
OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH