这样制成的薄膜可以被用来制造一种新型扩音器，这种扩音器通过加热和冷却空气工作，而不再是直接通过往复运动使空气产生振动效果。

These films can be used to make a new type of loudspeaker that works by heating and cooling the air, rather than bouncing up and down to vibrate the air directly.

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移动阴极：采用机械装置使被镀制件与极杠一起作周期性往复运动的阴极。

Mobile cathode: the mechanical device makes the plated with its poles together as a product of the periodic reciprocating motion cathode.

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摇动筛依靠曲柄连杆机构使筛箱作往复运动。

Shaking screen on crank-connecting rod for reciprocating motion to the sieve case.

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