This is because the tremendous heat produced from a nuclear blast causes an up-draft of air that forms the familiar mushroom cloud.

这是因为核爆产生的大量的热能会把空气往上吸入，形成令人熟知的蘑菇云状。

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The stars form when gas in the cloud condenses under its own gravity and becomes packed enough to ignite nuclear fusion.

星云中的气体在它的重力下凝聚形成新星，新星变得足够满以避免核聚变。

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Nothing Mr ElBaradei's men say looks able yet to dispel the cloud of Iranian secrecy and Western suspicion that hovers over Iran's nuclear programme.

巴拉迪的下属们表示，看来还没有任何东西能驱散笼罩在伊朗核计划上的伊朗秘密及西方疑虑的阴影。

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Last night, the Senate ratified the START II treaty, which, when Russia ratifies it, will enable us to make continued dramatic reductions of our nuclear arsenal and remove further the nuclear cloud from our children's future.

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In 1986, the fourth reactor at the Chernobyl nuclear complex in the Ukraine exploded and caught fire, spreading a radioactive cloud across Europe in the world's worst nuclear disaster.

CNN: Saturday,

It seems reasonable that the institutes should operate and collaborate within a secure cloud, similar to the networks where we store our nuclear secrets, tax records and military intelligence.

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