{TAIL ~ The reactor} is {HEAD ~ either a catalytic or non catalytic burner}, or a fuel reformer for converting a fuel to hydrogen 
{ TAIL ~ The reactor } is { HEAD ~ either a catalytic or non catalytic burner } , or a fuel reformer for converting a fuel to hydrogen
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH