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