While the upper cylinder gives more effect than the lower one that is located symmetry of the measure point.

而对某一固定测点而言，其受上方圆柱的影响要大于受下方圆柱的影响。

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In a typical setup, an upper cylinder will emit high-frequency sound waves that, when they hit the bottom, concave part of the device, are reflected back.

在一个典型的声悬浮装置中，缸体上部将发出高频声波，声波接触到底部凹面会被反射回来。

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SI-1 also contains detergents and a synthetic upper cylinder lubricant which will help clean the intake valves, pollution control valves, combustion chamber deposits and carburetors.

1依靠独特专用全合成技术， 可以非常有效的去处比如控制阀， 节气阀，燃烧室的积碳和凝胶。

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This chamber contains a slightly eccentric cylinder which can be rotated to make either the upper or the lower slots bigger.

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