{TAIL ~ The zirconia particles} are substantially non associated and have {HEAD ~ an average size} no greater than 50 nanometers and may contain yttrium 
{ TAIL ~ The zirconia particles } are substantially non associated and have { HEAD ~ an average size } no greater than 50 nanometers and may contain yttrium
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH