在棒-板间隙加一电压，棒为负极性时的击穿电压比棒为正极性时的间隙（）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='32664' and id < 2597822 and id<>'2597822' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='32664' and id > 2597822 and id<>'2597822' order by id asc limit 5