First, {HEAD ~ SOx} in {TAIL ~ the gas} is absorbed by the solution of polyethylene glycol 
in
First , { HEAD ~ SOx } in { TAIL ~ the gas } is absorbed by the solution of polyethylene glycol
OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH