Envoyer par SMS: Structure and Dielectric Behavior of Yb<sub>2</sub>O<sub>3</sub>-MgO Co-Doped 0.92BaTiO<sub>3</sub>-0.08(Na<sub>0.5</sub>Bi<sub>0.5</sub>)TiO<sub>3</sub> Ferroelectric Relaxor