LUO Jieyu (1994-), male, Master candidate. E-mail: 774500045@qq.com
0.65CaTiO3-0.35(La1-xCex)AlO3 (CTLCA-x) microwave dielectric ceramic was successfully synthesized by the polymeric precursor method using EDTA as a chelating agent. The effects of Ce3+ ion doping on the microwave dielectric properties, microscopic structure and crystal structure were studied. The result indicated that the sintering temperature of CTLCA-x ceramic prepared by polymer precursor method was decreased by about 125 ℃ compared with conventional mixed solid method, a single orthorhombic phase for all the compositions can form and the unit cell volume increases linearly with the doping content x. Ce3+ ion dopant can increased the quality factor and dielectric constant, but the temperature coefficient of resonant frequency decreased. When x = 0.2, the optimal microwave dielectric properties of εr=42.7, Q×f=39 159 GHz, and τf= -7×10-6/℃ for the CTLCA-0.2 ceramics could be obtained, which sintered at 1 325 ℃ for 3 h.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |