In the paper, it is introduced the content of silicon carbide in warming agent was determined with the combustion gas volumetric method by burning the sample at about 800 ℃ to remove the free carbon, dissolving carbonate with acid, filtration and washing. The determination conditions such as the temperatures of starting decomposition and complete decomposition for silicon carbide, preheating time and selection of sample weights are discussed as well as the optimum working conditions are found out. The measurement range of content of silicon carbide with this method was 1.00%~45.00%. 11 times of determination were carried out with 4 types of warming agent samples and the relative standard deviation (RSD) were 0.952%, 0.446%, 0.590% and 0.490% respectively. Compared with other methods, the results were the same.
| 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 |