This means that substantially {HEAD ~ all the catalyst} provided in {TAIL ~ the cell wall} 23 can contribute to conversion reaction of exhaust gas 
provided in
This means that substantially { HEAD ~ all the catalyst } provided in { TAIL ~ the cell wall } 23 can contribute to conversion reaction of exhaust gas
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH