摘要
报道一种合成２，２－二甲基－４－戊烯酸的新方法。由异丁醛与烯丙醇缩合得到２，２－二甲基－４－戊烯醛，后者经氧化银选择氧化生成２，２－二甲基－４－戊烯酸。此法氧化产率（９６％）高于分子氧氧化法（６１％）和歧化法（４１％）。反应中析出的金属银能定量回收，循环使用。
Cross flow ultrafiltration techniques have been used to extract colloidal organic carbon (COC) from seawater. Using UV/persulphate method, dissolved organic carbon (DOC) and COC of seawater in the southern Yellow Sea were measured in July 1998. The average concentration of DOC in the surface layer was 340.0μmol/L. The COC concentrations ranged from 30.2 to 125.0 μmol/L in the study area. On average, COC accounted for about 30.9% of the initial DOC, and the highest value of COC was 56.6%. The result indicates that colloids may play an important role in the biogeoche mical cycling of organic carbon. The fact that truly dissolved organic carbon (UOC) and COC showed little correlation indicates that the sources of colloids were very complicated.
关键词
二甲基
戊烯酸
二甲基戊烯醛
有机合成
cross flow ultrafiltration
colloidal organic carbon(COC)
dissolved organic carbon(DOC)
distribution
the southern Yellow Sea
