This mixture is then contacted with {TAIL ~ the remainder} of {HEAD ~ the electron donor or transition metal component} for a second contact time of less and 110 seconds 
This mixture is then contacted with { TAIL ~ the remainder } of { HEAD ~ the electron donor or transition metal component } for a second contact time of less and 110 seconds
OTH OTH OTH OTH OTH OTH 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