首次将顶煤的分类与直接顶、老顶的分类结果相结合，弥补了原有顶板分类方案不适合放顶煤采场的不足。

Combine top-coal classification with roof classification for the first time, which make up the inadequate of former classification program.

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烟煤的宏观煤岩分类是煤岩学研究的内容之一。

Macroscopic classification for bituminous coal is one of the research tasks for coal petrology.

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煤植体分类是煤植体研究的基础。

Classification of phyterals is the basis of the research.

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