The binary solid-liquid equilibrium of Dimethyl Terephthalate (DMT), Dimethyl lsophthalate (DMI) and Dimeth- yl Phthalate (DMP) was investigated by experiment and differential scanning calorimetry (DSC). The r...The binary solid-liquid equilibrium of Dimethyl Terephthalate (DMT), Dimethyl lsophthalate (DMI) and Dimeth- yl Phthalate (DMP) was investigated by experiment and differential scanning calorimetry (DSC). The result demonstrated DMT/DMI and DMT/DMP systems are eutectic while DMI/DMP is a solid-solution system. The eutectic temperature of DMT/DMI system is 336.7 K and that of DMT/DMP is 271.1 K. Furthermore, a classical solid-liquid phase equilibrium model was used to fit the experimental data of the eutectic systems of DMT/DMI and DMT/ DMP and the theoretical model could describe the eutectic solid-liquid phase diagrams properly.展开更多
The dielectric properties of Pb(Zn1/3Nb2/3)O3-PbZrO3-PbTiO3 (PZN-PZ-PT) system near the rhombohedral/tetragonal morphotropic phase boundary (MPB) are carefully studied in this paper.It is found that,for all samples,th...The dielectric properties of Pb(Zn1/3Nb2/3)O3-PbZrO3-PbTiO3 (PZN-PZ-PT) system near the rhombohedral/tetragonal morphotropic phase boundary (MPB) are carefully studied in this paper.It is found that,for all samples,the curves around the temperatures of dielectric permittivity peak show the characteristics of diffuse phase transition.The change in PbZrO3/PbTiO3 ratio has much influence on the dielectric properties of the samples.The extent of diffuse phase transition increases with the increasing Zr/Ti ratio.The samples in rhombohedral region have typical diffuse phase transition in the temperature range measured.However,for the samples with tetragonal symmetry,a spontaneous normal ferroelectric-relaxor phase transition exists at temperature lower than that of permittivity peak.This normal ferroelectric-relaxor phase transition is confirmed by the experiment of thermally driven current.The analysis of TEM reveals that the samples in tetragonal region show a 90° macrodomain structure,while the samples in rhombohedral region have the configuration of microdomain structure.展开更多
文摘The binary solid-liquid equilibrium of Dimethyl Terephthalate (DMT), Dimethyl lsophthalate (DMI) and Dimeth- yl Phthalate (DMP) was investigated by experiment and differential scanning calorimetry (DSC). The result demonstrated DMT/DMI and DMT/DMP systems are eutectic while DMI/DMP is a solid-solution system. The eutectic temperature of DMT/DMI system is 336.7 K and that of DMT/DMP is 271.1 K. Furthermore, a classical solid-liquid phase equilibrium model was used to fit the experimental data of the eutectic systems of DMT/DMI and DMT/ DMP and the theoretical model could describe the eutectic solid-liquid phase diagrams properly.
文摘The dielectric properties of Pb(Zn1/3Nb2/3)O3-PbZrO3-PbTiO3 (PZN-PZ-PT) system near the rhombohedral/tetragonal morphotropic phase boundary (MPB) are carefully studied in this paper.It is found that,for all samples,the curves around the temperatures of dielectric permittivity peak show the characteristics of diffuse phase transition.The change in PbZrO3/PbTiO3 ratio has much influence on the dielectric properties of the samples.The extent of diffuse phase transition increases with the increasing Zr/Ti ratio.The samples in rhombohedral region have typical diffuse phase transition in the temperature range measured.However,for the samples with tetragonal symmetry,a spontaneous normal ferroelectric-relaxor phase transition exists at temperature lower than that of permittivity peak.This normal ferroelectric-relaxor phase transition is confirmed by the experiment of thermally driven current.The analysis of TEM reveals that the samples in tetragonal region show a 90° macrodomain structure,while the samples in rhombohedral region have the configuration of microdomain structure.