距高倍数泡沫产生器的进气端小于或等于（ ）m处不应有遮挡物。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29272' and id < 2383459 and id<>'2383459' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29272' and id > 2383459 and id<>'2383459' order by id asc limit 5