简要介绍以此类方法对合成苯甲醛的研究.Based on the reactions , this paper reports research for synthesizing benzaldehyde.再溴代得到2-溴 -4,5-二甲氧基苯甲醛,收率为91.9%,并分析溴代过程中甲酰基的邻位效应及溴代产物的稳定性.This product with Br 2 was obtained 2 - bromo - 4,5 - hydroxy...
Ply change is big, face has bongo package, water proofing property of demonstrative face is poor.厚度变化大, 板面有小鼓包, 说明板面防水性差.These figures are demonstrative of our progress.这些数字表明了我们的进步.He greeted us in a demonstrative manne...
你听说过海洛德·梅尔文 和 蓝调乐队 吗 ?You ever heard of Harold Melvin & The Blue Notes?当然,切分音和蓝调只是爵士的一部分.Of course syncopation and blues are only part of the jazz picture.在蓝调音乐的萌芽时期,黑人占了艺人与听众的绝对多数.Both audience and player alike were pre...