Due to the prodigious proportion of medium and big electronic equipment in power line, the research of three phase reversible converter is becoming the researching hotpot on international and native.

由于中大功率的电力电子设备在电网中占很大的比重，因此高功率因数的三相可逆变流器的研究已成为当今国内外研究的一大热点。

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Conditional (reversible) male sterile line in plants would be fertile under special conditions, and thus could be used as two-line to produce hybrid seeds.

条件型雄性不育是指植株在特定的条件下育性相互转换，可以作为两用系，用于两系法杂交制种。

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