Part of the crack is cut by drill, the crack surface is dust-colour under naked eyes.

钻孔截取裂纹局部，肉眼可见裂纹表面呈暗褐色。

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A crack surface displacement of four-point-bend specimen under three types of loading is studied in this paper.

研究了四点弯曲型试件在各种类型载荷作用下的裂纹面位移，并考虑了裂纹尖端塑性区对它的影响。

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The former is collocated exclusively on the uncracked boundary, and the latter on one side of the crack surface.

位移边界积分方程的源点配置在非裂纹边界上，面力边界积分方程的源点配置在裂纹面上。

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Emily Haines' songs are like candy-coated insects: Once you crack their sugary shells, they're not as sweetly inviting as they appear on the surface.

NPR: Metric: Sweet Pop With A Bitter Center

Rather, as a consequence of injecting water and sand into the shale formation to crack the rocks so gas and oil will flow, massive amounts of waste water comes back to the surface with significant amounts of contaminants as a result of leaching out salt, heavy metals and trace amounts of radioactive materials from the rock formation itself.

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