镭-226的半衰期为

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29408' and id < 2394697 and id<>'2394697' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29408' and id > 2394697 and id<>'2394697' order by id asc limit 5