The removal of a neutron from the system is indicated by the head of an arrow.

用箭头表示一个中子从这个系统中的移动。

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Arrow: Printing fault in gravure which appears as a mark in the shape of an arrow head on the print. Also called comet.

箭形印记：是照相凹版印刷的瑕疵。印刷品上带有像箭头的印纹。亦称慧星印记。

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All of a sudden, the small gray doves Akira the next head, brush pull, fly up, like an arrow Li Xian, targeting large black cat forehead children, mercilessly in a peck.

霎时间，小灰鸽晃了下脑袋，刷拉一下，飞了起来，象一只离弦的箭，对准大黑猫的脑门儿，狠狠地啄了一口。

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The search turned up traces of the building, and then something altogether more exciting: A human skeleton, complete with evidence of battle wounds -- a blow to the head, and an arrow in the back -- and scoliosis, or curvature of the spine.

CNN: Richard III: The mystery of the king and the car parking lot