An organic coordination (complexing) compound in which the metal ion is bound to atoms of nonmetals, e. g. nitrogen, carbon, or oxygen, to form a heterocyclic ring having coordinate covalent bonds.

一种配位(络合)化合物，其中的金属离子与氮、碳或氧等非金属原子结合生成有配位共价键的杂环。

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Thymine: Organic compound of the pyrimidine family, often called a Base, consisting of a ring containing Both nitrogen and carbon atoms, and a methyl group.

胸腺嘧啶：一种嘧啶类有机化合物，通常叫做基底，由含有氮和碳原子以及甲基的环形物组成。

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PCB (polychlorinated biphenyl) : Any of a class of highly stable organic compounds prepared by the reaction of chlorine with biphenyl, a two-ring compound.

多氯联苯：任何一种由氯与联苯反应生成的非常稳定的二环有机化合物。

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