目前，通信用多模光纤的纤芯直径为 。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30263' and id < 2448228 and id<>'2448228' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30263' and id > 2448228 and id<>'2448228' order by id asc limit 5