为了区别不同方向的流动波，波阻抗有正、负号。（）

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SQL Error: select id,body,options from ***_enewstiku where sourceid='32666' and id < 2598109 and id<>'2598109' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='32666' and id > 2598109 and id<>'2598109' order by id asc limit 5