carbon-graphite impregnated with inorganic salt

例句：

1. 1. The graphite carbon isused in the production of pencils andpens.
   石墨碳用于生产铅笔和钢笔。
2. 2. The graphite carbon is a goodmaterial for making batteries.
   石墨碳是一种制作电池的好材料。
3. 3. The graphite carbon isalso used in the manufacturing of electronic devices.
   石墨碳还用于制造电子设备。