DETERMINATION OF STRUCTURE AND DIELETRIC, ELASTIC AND PIEZOELECTRIC COEFFICIENTS IN FERROELECTRIC SINGLE CRYSTALS Pb_xBa_(1-x)Nb_2O_6 AND Li, Na-DOPED Pb_xBa_(1-x)Bb_2O6

• 铁电晶体Pb_xBa_(1-x)Nb_2O_6和掺Li,Na的Pb_xBa_(1-x)Nb_2O_6的结构和电弹张量的测定