A cylinder (Fig. 1) is a hollow tube with a closed concave base that permits the cylinder to stand upright.

钢瓶(图1)是中空的管道，封闭的底部是凹入的，这样可以直立起来。

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When a cylinder with this valve configuration is in the upright position, the inlet of the tube is immersed in liquid and the liquid phase will be removed.

当带有这种阀门配置的钢瓶处在垂直位置时，管子的入口浸在液体中，就可以提取液相产品。

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Under the frequency of resonance, small particles which are in the bottom of an upright standing wave tube will rise and move to the node, or loop planes, and keep suspending there.

竖直放置的驻波管在共振频率下，位于其管底的微小颗粒群会在一定声压级下产生悬浮现象，即腾空而起，悬浮在波幅波节平面。

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The wraparound labels on conventional round bottles were difficult to read, so she designed a flat tube-shaped container that stood upright on its cap, with plenty of room for a large, flat label that could be read easily at a glance.

WSJ: When Simplicity Is the Solution