铝活塞的表面常常镀锡，以便在发动机开始运转阶段能进行适当的磨合。

Often, aluminum pistons are tin-plated to allow proper break-in when the engine is started.

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在基线运转中有两个特别的阶段：一个 24 小时的“初始测试”，接下来是压力可靠性运转阶段，或者说是“压力测试”。

There were two unique phases in the baseline run: a 24-hour "initial test," followed by the stress reliability run phase, or "stress test."

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科学家们已经可以识别不同的睡眠阶段，而且发现，人在睡眠很少的情况下，机体仍然很好的运转，但只是在睡眠时做了梦才如此。

Scientists have identified various stages of sleep, and they have found that humans can function well on very little sleep, but only if they dream.

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