Piezoelectric nanomaterials (PNs) are attractive for applications including sensing, actuating, energy harvesting, among others in nano-electro-mechanical-systems (NEMS) because of their excellent electromechanical coupling, mechanical and physical properties. However, the properties of PNs do not coincide with their bulk counterparts and depend on the particular size. A large amount of efforts...

We formulate and study the model variational problem describing phase transitions in two-phase media. Based on this study, we obtain an information about properties of solutions to equilibrium a medium traditional statement.