6

Room temperature aerobic oxidation of alcohols using CuBr 2 with TEMPO and a tetradentate polymer based pyridyl-imine ligand

ty10086 提交于 周四, 08/26/2021 - 13:42
Abstract(#br)A series of tetradentate pyridyl-imine terminated Schiff-base ligands has been investigated for their ability in the catalytic oxidation of alcohols when combined with copper bromide (CuBr 2 ) and 2,2,6,6-tetramethylpiperidyl-1-oxy (TEMPO). Analogous bidentate ligands showed poorer catalytic activity and the ratio of Cu:ligand was of crucial importance in maintaining high yields.

鳕鱼肝油中多氯代正构烷烃的直接浸泡薄膜固相微萃取

ty10086 提交于 周三, 08/25/2021 - 15:52
采用薄膜-固相微萃取( TF-SPME )方法对市售鳕鱼肝油样品中5种单体多氯代正构烷烃( PCAs )进行检测。通过制备一种新型的铝负载亲水-亲油平衡/聚二甲基硅氧烷( HLB / PDMS ) TF-SPME装置,实现了鱼油的直接浸泡萃取。基质匹配校正线性范围为0.075 ~ 0.75   µ g / g,方法定量限( MLOQ )为0.07 ~ 0.217   µ g / g。采用与外部校准斜率相当的其他鱼油进行标准加入校准。作为概念的证明,对4个鱼油品牌进行了污染物检测,1,1,1,3 -四氯癸烷、1,2,9,10 -四氯癸烷、1,2,13,14 -四氯十四烷和1,1,1,3,14,15 -六氯十五烷在MLOQ以上但低于斯德哥尔摩公约规定的范围。该方法为使用廉价、可重复使用的微萃取装置从油性基质中清除和富集PCAs提供了一种有效的方法,可限制样品制备协议对环境的影响。