下列变化不属于氮的固定的是（   ）  

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='19684' and id < 1704424 and id<>'1704424' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='19684' and id > 1704424 and id<>'1704424' order by id asc limit 5