The fracture phenomenon and spalling time of the test piece can be observed continuously through a sight hole.

通过窥视孔可连续观察试件表面的脱皮现象和得出激热开裂时间。

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A few years ago scientists were surprised by the sight of two planes carving a hole through a cloud—which then began spewing snow.

几年前，科学家对两架飞机在云中形成一个空洞，随后开始飘雪的现象很是惊异。

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Over time, tides filled the hole with sand and water, creating a secluded watery Eden where determined beach bums can swim, sunbathe and kayak largely out of sight.

时间一长，潮水带来的细沙和海水覆盖了这个炸弹洞，造就了这个远离喧嚣的海上伊甸园，海滨达人在这里游泳，晒日光浴，划皮艇。

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But even as we dig our way out of this deep hole, it's important that we not lose sight of what led us into this mess in the first place.

WHITEHOUSE: The ��Volcker Rule�� for Financial Institutions

Thus, the outline of the black hole would be detectable as they move across our line of sight.

FORBES: Free-Floating, Nearby Black Holes Detectable By Decade's End, New Study Reports