ENIG化学镀镍浸金enn.半方；N 字prep.作为；一起；在 ... 中EN tandem accelerator EN串列式加速器enantiotropic transition对映性变换enzymological properties酶学性质enzymatic polymerization酶促聚合enlarging and excavation扩挖envizonmental diseconomy环境不经济enviromnental protection环保enumeration optimization穷举优化enzootic bovine leukosis牛地方流行性白血病Enlarging shield tunnels盾构扩挖法