暴露于大气中的铝表面呈现三层结构，即氧化铝和氢氧化铝层、其上的腐蚀产物层和最上层的污染物沉积形成的污染物层。

A three layer of aluminum exposed to atmosphere is identified: the aluminum and its native oxide, the corrosion layer atop oxide aluminum, and a surface contamination layer.

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Katz博士和他的同事们发现, 在钠β-氧化铝中, 虽然钠离子流很容易在相邻的氧化铝层之间流动, 但是它们无法从中穿过.

Dr Katz and his colleagues found that, although sodium ions flow readily in between adjacent aluminium-oxide layers of sodium beta-alumina, they cannot pass between them.

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复合管从里到外由氧化铝陶瓷层、金属过渡层、白口铸铁层、碳原子扩散层、球墨铸铁层组成。

From inner to outside, the composite pipe consisted of alumina ceramic layer, metal transition layer, white cast layer, carbon atom diffusion layer and nodular cast iron layer.

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