A flange is arranged under the reaction tube and provided with a positioning convex block.

在反应管下面设有法兰盘，该法兰盘上设有一个定位凸块。

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Here's a way that you can do it in a test tube without using any cells by this process called Polymerase Chain Reaction.

但有一个方法可以让你在试管中完成,不用细胞,这个方法叫聚合酶链式反应

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Once an isotope causes the crystal to flash, a photosensitive cathode releases electrons into a vacuum tube where a chain reaction produces a cascade, as in the Geiger counter.

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