Europa is covered in a shell of water ice that's thought to hide an ocean of liquid water below. Liquid water is a key ingredient for life as we know it.

木卫二由水冻冰层所覆盖，人们认为其下流动着大量的液态水，而正如人们所知，液态水是生命存在的重要因素。

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The failure mechanism of a roll shell in continuous roll casting is discussed and a formula for predicting its fatigue life is established.

分析了铸轧辊套的失效机理；提出了铸轧辊套疲劳寿命预报公式。

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The utility model provides a reboiler with longer service life, aiming at solving the problem that the shell and tube heat exchanger in the existing reboiler often has short service life.

本实用新型提供了一种使用寿命较长的再沸器，以解决现有再沸器中列管式换热器使用寿命短的问题。

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Mr Phillips said they were covered in dead plant and shell life which suggested they had been exposed before.

BBC: Rhossili beach looking towards Llangennith

McClaren sat shell-shocked in his dug-out as England looked to be throwing away the life-line handed to them by Israel after their win over Russia -- and they left the field at half-time to a chorus of boos.

CNN: Croatia crush England Euro dreams