其金属取代物能和环戊酮顺利地反应得到40.Its metallation and addition to cyclopentanone proceeded well to 40.以单质碘为催化剂合成了环戊酮乙二缩酮.Cyclopentanone ethylene ketal was synthesized with I _ 2 as catalyst.比较研究了三种含苄叉环戊酮基团的新型香豆素类光敏染料.Absorption spect...
On a cold day there can be quite a draught from the letterbox.天冷的时候能明显感觉到从信箱那边吹来的过堂风。Peep through the letterbox and see if anyone is at home.透过信箱看家中是否有人.I personally saw him put the letter into the letterbox.我亲眼看见他把信投送到信...
上皮细胞的顶膜显然是必要的.The apical membrane of the epithelial cells is apparently essential.较小支气管的上皮破裂和部分脱落.The epithelium of the smaller bronchi was fragmented and partially desquamated.愈合过程的主要组成部分,是上皮形成.The dominant components o...