根据物质分子大小差别进行分离，常用的方法有

试卷相关题目

SQL Error: select id,body,options from ***_enewstiku where sourceid='29376' and id < 2392725 and id<>'2392725' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29376' and id > 2392725 and id<>'2392725' order by id asc limit 5