There are many reasons for a needing a fifth auxiliary component called the Controller. Some of these reasons are.

需要第5个辅助组件Controller的原因有很多，这是其中的一些。

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The invention comprises a main agent and an auxiliary component; the main agent component is aluminum potassium sulfate or aluminium ammonium sulfate.

本发明包括主剂和辅剂成份，主剂成份为硫酸铝钾或硫酸铝铵。

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Curved diffuser is an important auxiliary component of main fan installations of mine, whose performance directly influences the operating efficiency of the installations.

扩散弯道是矿井主要通风机装置的重要辅属装置，其性能的优劣直接影响通风机装置的运行效率。

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