varying either said partial pressure of reactants or said coolant flow rate to maintain {HEAD ~ said sensed temperature} to said {TAIL ~ highest temperature level} at said outlet side 
varying either said partial pressure of reactants or said coolant flow rate to maintain { HEAD ~ said sensed temperature } to said { TAIL ~ highest temperature level } at said outlet side
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH