The batteries are designed to be leak-proof and hermetically sealed.

这些电池的设计防渗漏，且密封性强。

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The containment structure is a hermetically (air tight) sealed, very thick structure made of steel and concrete.

它是高度密封，用钢铁和混凝土制成的非常厚的壁障。

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The third containment is a hermetically (air tight) sealed, very thick bubble of the strongest steel and concrete.

第三个容器是严格密封的，用很厚的钢铁和混凝土打造的气泡状容器。

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We control how we use time, we control the temperature in the environment, and hermetically seal ourselves in things.

我们控制时间的利用，我们控制周边环境的温度,我们把自己封闭在各种事务中，与世隔绝。

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And there is no way that you can hermetically seal Westminster from this process.

BBC: News | UK Politics | Charles Kennedy's speech in full

It would not be a hermetically sealed conversation (for the most part) between the meter and the utility.

FORBES: The Economist: Innovation Almost Dead. Perhaps Not So In Electricity

One answer is to use the energy to compress air, which can be squirrelled away in hermetically sealed underground caverns.

ECONOMIST: Compressed air might help to make wind power more reliable