用授予某一体积元内物质的辐射能量除以该体积内的物质的质量，得到的是

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29509' and id < 2400284 and id<>'2400284' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29509' and id > 2400284 and id<>'2400284' order by id asc limit 5