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='23346' and id < 2038275 and id<>'2038275' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='23346' and id > 2038275 and id<>'2038275' order by id asc limit 5