Particulates in {HEAD ~ the trap} are ignited and burnt off by exhaust gas {TAIL ~ whose temperature} has been raised by the electric heater 
Particulates in { HEAD ~ the trap } are ignited and burnt off by exhaust gas { TAIL ~ whose temperature } has been raised by the electric heater
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH