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