The crystal is shiny glass, but is common to the oil sheen on the surface of fracture.

晶面呈玻璃光泽，但常见到的是断口面上的油脂光泽。

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The chemical composition, metallographic structure, hardness and surface of fracture are analyzed herein for the broken blade and lacing wire in order to find the cause of blade fracture.

针对断裂叶片及拉筋进行了化学成分、金相组织、硬度、断口等分析，以便找到叶片断裂的原因。

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The fault, fracture, unconformable surface and reservoir are the major channels of hydrocarbon migration in gentle slope belt.

断层、裂缝、不整合面和储层是缓坡带油气运移的主要通道。

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For more than six decades, gas companies have been using advanced technologies to hydraulically fracture and safely procure natural gas from up to two miles beneath the surface of the earth.

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