The bead may optionally be converted to {TAIL ~ a phosphate} or other {HEAD ~ desired phase} by hydrothermal treatment after gelation and prior to sintering 
The bead may optionally be converted to { TAIL ~ a phosphate } or other { HEAD ~ desired phase } by hydrothermal treatment after gelation and prior to sintering
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH