本文从生产型煤和型焦的需要出发，研究岩浆变质作用所形成的天然焦炭和高、中变质煤的显微结构。

The paper studies the microstructures of the cokeite and the high, middle metamorphic coal, formed by the metamorphism of magma in view of the need for producing moulding coal and coke.

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人造石墨、煅烧石油焦、天然石墨、焦炭、以及用这类材料配成的混合料。

Commonly used for cast iron carbon additive materials are: artificial graphite, calcined petro coke, nature graphite, coke, and as the mixture with these materials.

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人造石墨、煅烧石油焦、天然石墨、焦炭、以及用这类材料配成的混合料。

Commonly used for cast iron carbon additive materials are: artificial graphite, calcined petro coke, nature graphite, coke, and as the mixture with these materials.

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