natural character of coal

• 煤质特征

natural character of coal的用法和样例：

例句

1. At the same time it analyzes systematically the characteristics of coal petrology and coal quality of mineable or partly mineable coal bedding in Taiyuan Formation.
   同时对太原组各可采或局部可采煤层的特征及煤岩煤质特征进行了系统的分析。