학술저널
This study was carried out to determine the content of heavy metals in chalks. Samples were collected from 5 manufacturing companies of chalk. The content of lead and cadmium were analyzed by flame atomic absorption spectrophotometer. The results obtained were as follows: 1. The average content of lead was 22.0 ppm, and the range 6.4 - 50.9 ppm. 2. The average content and the range were 4.1 ppm and 2.8 - 4.8 ppm respectively.
Ⅰ. 緒論
Ⅱ. 實驗材料 및 方法
Ⅲ. 實驗結果및 考察
Ⅳ. 結論
(0)
(0)