LI Zixuan (1994-), female, Master candidate. E-mail: 540821134@qq.com
Al(CON2H4)6Cl3 was firstly synthesized as a precursor with urea and AlCl3·6H2O as a nitrogen source and an aluminum source, respectively, and then the precursor was calcined at 1 000 ℃ to prepare spherical h-AlN nanoparticles. The effects of atmosphere pressure and sintering time on the morphology and the nucleation-growth mechanism of AlN were investigated. The results show that spherical AlN particles with the sizes of 320-460 nm are formed by equiaxed fine grains of smaller than 10 nm and amorphous phase under N2 pressure of 0.1-0.2 MPa. As the N2 pressure increases to 0.5 MPa, the diameter of spherical AlN increases to 650 nm, and rod-shaped AlN crystals appear in the aggregates. The size and number of rod crystals increase as the sintering time increases. AlN nanoparticles are formed by the reaction of AlCl3 and NH3 due to the decomposition of the precursor. The gas phase saturation in the crucible increases as N2 pressure increases, promoting the nucleation and growth of AlN, reducing the amorphous phase content, and enhancing the crystallinity of AlN.
| 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 |