黄土高原半干旱的气候条件、稀疏的植被和疏松易蚀的黄土物质，是该地区高含沙水流形成的自然地理因素。

Semi arid climate, poor vegetation cover and highly erodible loess can be regarded as the main natural factors responsible for the formation of hyperconcentrated flows in the Loess Plateau, China.

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前言： 常规的铝合金碱蚀工序时间长，易产生“过腐蚀” ；

For normal alkali corrosion procedure of aluminum alloy, the treatment time is long, and exceeding corrosion will occur.

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