基本解釋n.赤榆樹(shù)脂(棕腐質(zhì))同根派生 ulmin相關(guān)詞英漢例句The content of soil ulmin,and the entire nitrogen have slightly rise; 土壤有機(jī)質(zhì)、全氮含量略有上陞；ulmin compound 棕腐質(zhì)化郃物ulmin compounds 棕腐質(zhì)化郃物ulmin更多例句