R ” 是取化基,如乙氧基 、 甲氧基及它们的环氧和烷氧同系物或卤基.R " is a replaceable function , e . g . acetoxy, methoxy, their acyloxy and alkoxy homologs or halo.蒸馏得质量分数高于98%的邻乙氧基苯甲酸,收率为92%.Distillation gave o ethoxybenzoic acid with 98 % of the p...
Lifelines would be of no help until the product is selling.如果产品卖不出去,这些救命资金也毫无帮助.They firmly lay hold of all the lifelines of their national economy.他们牢牢地控制住国民经济的命脉.They firmly took hold of all the lifelines of their nati...