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.

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.

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Thus gives you alumina, aluminium oxide, which you then put through a smelter to make aluminium metal.

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And the reason why you need two tonnes to make one tonne is that alumina is aluminium oxide (Al2O3).

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