The magnetic duct is also constructed to eliminate {HEAD ~ other undesirable particles} that result in {TAIL ~ a coarse grain film} 
result in
The magnetic duct is also constructed to eliminate { HEAD ~ other undesirable particles } that result in { TAIL ~ a coarse grain film }
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL