Thus, the nanoparticles and TiO2 interact by {HEAD ~ a mechanism} resulting in {TAIL ~ improved spacing} of the TiO2 particles 
Thus , the nanoparticles and TiO2 interact by { HEAD ~ a mechanism } resulting in { TAIL ~ improved spacing } of the TiO2 particles
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH