以正庚醛 、 硫代硫酸钠和溴代正丁烷为原料,合成了正庚醛正丁硫醇缩醛.The heptanal butyl mercaptan was synthesized with heptanal, sodium thiosulfate and 1 bromobutane as raw materials.目的研究以庚醛和原甲酸三乙酯为原料制备庚醛二乙缩醛的工艺条件.Aim Enanthal diethyl acetal is prepared ...
Who can deny his stature as the world's greatest cellist?谁能否认他是世界上最伟大的大提琴演奏家呢？The cellist's bowing was very sensitive .那位大提琴手的弓法十分细腻。World - renowned cellist Yo - Yo Ma founded The Silk Road Project in 1998.世界闻...
青足鹬产于欧洲的一种涉禽 ( 鹬属青脚鹬 ),腿绿色,喙长.A European wading bird ( Tringa nebularia ) having greenish legs and a long bill.它的喙长得象一根垒球棒, 尖得象一把细长的利剑.It looks like the beak of a softball stick, like a slender tip of the sword....