Fuel assembly is a cylindrical pellets made of uranium dioxide fuel rods, and then assembled according to a certain order.

核燃料组件是由圆柱状的二氧化铀芯块做成的燃料棒，然后按照一定顺序组装起来。

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But in terms of the different types of reactors the fuel form is the same uranium dioxide.

但是关于不同种类的反应堆，燃料的形式是相同的，二氧化铀。

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Each fuel assembly is typically used in the reactor for 4 to 6 years, after which most of the fuel it contains is spent, and the uranium dioxide is no longer cost-efficient at producing energy.

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