I mean, arc length could be positive or negative.

我意思是弧长可正可负。

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The plasma source ion implantation device consists of pulsed negative high voltage power, hot cathode arc discharge system, vacuum chamber and target stage, vacuum system and monitor system.

等离子体源离子注入装置由脉冲负高压源系统、热阴极弧放电系统、真空室及样品台、真空系统和监测系统等五部分组成。

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Tetrahedral amorphous carbon (ta-C) films have been deposited on P-type (100) polished c-silicon wafer with different substrate negative bias by filtered cathodic vacuum arc technology.

采用过滤阴极真空电弧技术并施加一定的衬底负偏压，在P（100）单晶硅片上制备出四面体非晶碳薄膜。

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In the modern history of the Catholic Church, "no other story has drawn such negative coverage over this arc of time, " says Allen.

FORBES: Media

This negative is illuminated from the front by an arc lamp, and the light from this lamp passes through the transparent regions of the liquid-crystal layer to the middle layer.

ECONOMIST: Curtains for celluloid