LI Lei (1981-), male, Ph.D., Associate Professor. E-mail: zjulilei@zju.edu.cn
Low-dielectric-constant (εr) microwave dielectric ceramics are one of the key materials for future mobile communication technology, and the accurate characterization for their basic performance parameters of εr, Qf value and temperature-dependent coefficient of resonant frequency (τf) is one of the most fundamental issues. Parallel plate method and metal resonant cavity method with TE011 mode are commonly used for measuring the microwave dielectric properties. However, the corresponding problems are neglected, which are especially important for the research and applications of low-εr microwave dielectric ceramics. In this review, the key problems of the identification of TE011 resonant mode, measurement reliability of Qf value and measurement reliability of τf were discussed for the characterization of low-εr microwave dielectric ceramics, and the corresponding solutions to the problems were given.
| 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 |