When nuclear fuel is manufactured it is encased in metal cans.

核燃料生产出来时被装在金属罐中。

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Spark plugs only ignite the fuel mixture near the spark gap, reducing the combustion efficiency, and the metal that makes them up is slowly eroded as they age.

火花塞只点燃火花隙附近的燃料混合物，这就降低了燃烧效率，并且随着使用年限增加火花塞中的金属慢慢被侵蚀。

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Other price increases, of fuel, glass and metal, add to the pressure.

其他物价的上涨，如燃料，玻璃和金属，又使压力持续增强。

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Investors had been further spooked by an explosive bubble in the uranium market, the metal used to fuel nuclear reactors.

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The little bit of this that interests me is that those fuel cells use my favourite metal, scandium, as an integral part of their operation.

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It involves taking oxygen to the fuel not as a gas, but bound to a metal such as iron or calcium, and should in principle make combustion more efficient.

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