【摘 要】
：
A new niobate Ba6Mg0.67Nb9.33O30 was synthesized in the BaO-MgO-Nb2O5 system by solid state reaction at 1350 ℃ for 48 h . The structure and dielectric properti
【机 构】
：
State Key Lab of Advanced Tech. for Mater. Synthesis and Processing
【基金项目】
：
Foundation of WHUT;Major Program of MOE;国家自然科学基金
论文部分内容阅读
A new niobate Ba6Mg0.67Nb9.33O30 was synthesized in the BaO-MgO-Nb2O5 system by solid state reaction at 1350 ℃ for 48 h . The structure and dielectric properties of Ba6Mg0.67Nb9.33O30 were determined by X-ray powder diffraction, scanning electron microscopy and dielectric measurements. The results show that Ba6Mg0.67 Nb9.33O30 belongs to ferroelectric phase of filled tetragonal tungsten bronze structure at room temperature with unit cell parameters: a = 1.26052(4) nm, c = 0.40045(2) nm, space group P4bm, calculated density 5.707g·cm-3.Ba6Mg0.67Nb9.33O30 belongs to relaxor ferroelectrics undergoing diffusive phase transition,and the transition temperature ( Tc ) is 30 ℃ observed at 10 kHz. At room temperature, Ba6Mg0.67Nb9.33O30ceramic has a high dielectric constant 850 at 1 MHz and a low dielectric loss of 0. 0052.
其他文献
CexZr1-xO2 complex oxides doped by transition metal(Fe, Mn, Cu) were prepared by precipitation method. Thermal stability of samples was characterized by XRD, su
The filling and solidification in centrifugal field, as well as the forming mechanism of off-center porosities were summarized, based on the mathematical model
A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc (GTA) welding pool with different sulf
Turbulent swirling flows and methane-air swirling diffusion combustion are simulated by both large-eddy simulation (LES) using a Smagorinsky-Lilly subgrid-scale
Al-alloy (AA5022) corrosion penetration (CP) and crystal structure were investigated after running static immersion corrosion tests in 1 mol/L HCl solution and
The phase diagrams of microemulsion CTAB/butanol/cyclohexane/aqueous solution of nitrate (or aqueous solution of ammonium salt) were determined and the structur
The microstructural evolution of the A2017 semi-solid alloy billets provided with rheocasting and extruding/extending forming by shearing-cooling-rolling(SCR) t
The reduction of TiO2 to Ti2O3 with hydrogen cold plasma generated by a DC pulsed glow discharge was realized under 2 500 Pa at 1 233 K. Only a little of Ti10O1
Nanosized (La0.47Gd0.2)Sr0.33MnO3 perovskite oxides were prepared at relatively low calcinating temperature of 600 ℃ and 800 ℃ for 10 h using amorphous comple
SrGdGa3O7:RE (RE=Ce3+, Pr3+, Tb3+) were prepared by traditional solid-state reaction and their luminescence properties in the range of VUV-Vis were investigated