The air of close cabin can't exchange with that of atmosphere, the harmful impurity must be wiped off from cabin, in which the purity and element of gas needed can be maintained.

封闭舱室不能与大气中的空气进行交换，必须去除舱室中有害杂质，维持必需的气体成分和纯净度，需要一套有效的空气调节和再生装置来完成这一任务。

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Purifying Gallium Only by this way, because of some major impurities separated out seriously, often forms individual impurity element to exceed mark, and causes product grade to reduce.

单一电解法提纯镓，由于一些主要杂质析出严重，常常形成个别杂质元素超标，造成产品品级降低。

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The interference effects of matrix element Fe and high concentration elements Nd, Dy, Co, B on impurity elements were studied.

研究了基体元素铁、主量元素钕、镝、钴、硼对杂质元素的光谱干扰情况；

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