CAI Wenjie (1993-), male, Master candidate. E-mail: 1132826171@qq.com
Hexagonal mesoporous silica (H-mSiO2) particles were prepared via an alcohol/water mixed reaction system using cetyltrimethyl ammonium bromide as a template. The resultant products were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform spectroscopy, thermogravimetric analysis-differential scanning calorimetry, and nitrogen adsorption/desorption measurements. As an alcohol/water volume ratio decreases slowly, the morphologies of samples change from spherical/ellipsoidal to spherical and then to necked or peanut-like. Based on the polishing tests over oxide films (about 208 nm), the developed H-mSiO2 abrasives contribute to the reductions of surface roughness and topographical variation, compared to non-porous sphere SiO2 (sSiO2) particles. The root-mean-square roughness of oxidized silicon wafers reduces from (1.27±0.15) nm to (0.25±0.01) nm after polishing with H-mSiO2 containing spherical and ellipsoidal particles. The maximum asperity height in sectional profiles decreases from 3.59 nm to 0.72 nm, and the maximum valley depth also reduces from 3.16 nm to 0.69 nm. Moreover, H-mSiO2 abrasives with uniform spherical shapes achieve a removal rate of (223±17) nm/min.
| 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 |