This paper describes corrosive certainty and gravity for ageing aircraft, and poses a series of measures preventedand controlled corrosion of ageing aircraft.

本文阐述了老龄飞机腐蚀的必然性和严重性，同时也提出了预防和控制老龄飞机腐蚀的一系列措施。

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Solidified water flows into balance jar upon itself gravity. Keeping certain water level in the jar through an automatic controlled discharge valve, which forms a water seal.

凝结水靠本身重力流入平衡罐，通过自动控制的排水阀，保持罐内的一定水位，形成水封。

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Be sure to perform exercises in a controlled manner rather than using momentum and gravity to lift and lower the weights.

CNN: How much weight is needed to strengthen my bones?