Valves are manufactured and assembled without exposure to silicone compounds.

阀门在制造和组装过程中，没有暴露在含硅酮的环境中。

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According to Barnant, the pumps are self-priming, can operate dry without damage, are suitable for slurries and viscous liquids, and contain no valves or seals.

泵是自我启动式的，可以进行空转，并不带来任何的损耗，非常适合于泥浆和胶黏性液体，不带有阀门和密封。

youdao

Valves are manufactured and assembled without exposure to silicone compounds.

这些阀门都是在没有硅酮成分的环境下制造和组装的。

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Like early horns, early trumpets were "natural" instruments, without valves.

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Without the safety valves of emigration to Europe, which is getting harder, and families' willingness to support those out of work, Morocco would look far less stable.

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Now some patients are getting such repairs for valves, irregular heartbeats, holes in the heart and other defects without major surgery.

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