The step of improving {HEAD ~ the dispersion} of {TAIL ~ the particles} in the washed suspension may be carried out by sonication 
of
The step of improving { HEAD ~ the dispersion } of { TAIL ~ the particles } in the washed suspension may be carried out by sonication
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH