Comment on 'Fabrication of uniform core-shell structural calcium and titanium precipitation particles and enhanced electrorheological activities'.

This comment is an analysis of the static yield stress of core-shell structured SiO(2)-calcium-titanium precipitation (CTP) particle-based electrorheological (ER) suspensions under various applied electric field strengths. We find that our previously published universal yield stress equation covers both polarization and conduction regions while the polar-molecule-based linearity mechanism becomes dominant for the giant ER fluid beyond the second critical electric field strength.