离心泵动密封摩擦副的材料一般不采用（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='24888' and id < 2124235 and id<>'2124235' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='24888' and id > 2124235 and id<>'2124235' order by id asc limit 5