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The urea-formaldehyde resin was made from industrial 36% formalin and 46% N carbamide in the laboratory. The urea-formaldehyde resin was used to imbed the insect specimens. 本文探討了在實驗室條件下利用工業(yè)用36 ％ 甲醛和含氮46％ 農(nóng)用尿素合成脲醛樹脂包埋昆蟲標本的方法。