本文介绍了一种新型的空气负离子发生器。

This paper introduces a new air negative ion producer .

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而且针叶林下的空气负离子浓度和空气质量要好于阔叶林。

And under conifer forest, the air-anion concentration and ability of air was higher than broadleaf forest.

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空气在这段时间当中富含有益的负离子，因此非常新鲜。

At this time, the air is very fresh with lots of beneficial negative ions.

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