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...
The glacier scooped a canyon out of rocks.冰河在礁石中冲出了一条河谷.The upper surface of glacier is riven by crevasses.冰川的上表面已裂成冰隙.the deceptively smooth surface of the glacier看似光滑的冰川表面Warmer conditions can send meltwater to the gla...