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如何用蒽酮鉴定糖,钼酸铵鉴定磷各位前辈好! 学生有个样品需鉴定其中是否含有糖以及磷。老师要求用蒽酮鉴定糖,用钼酸铵鉴定磷。学生不知该怎么做,还请哪位前辈指点一二!小弟感激不尽!
EN14372:2004测试邻苯二甲酸酯,样品恒重之后用乙醚萃取6h,继续恒重,继而加正己烷冲洗若干遍并定容,之后就直接装GC样品瓶,进而用GC/MS测试。整个过程都没提到是否要过层析柱进行分离净化.请问EN14372:2004测试邻苯二甲酸酯前处理是否要经过层析柱分离净化??(主要测试对象为PVC、PC、ABS、PPO等胶料中的邻苯二甲酸酯含量)
看了下EN14372的6.3.2测试邻苯,好像和一般的索氏提取很不一样,哪个真正按标准做过?到底怎么做啊。有没有EN14372的作业指导书啊?Place the sample in a pre-weighed 150 ml flat bottomed flask and heat in an oven at (105 ± 5) °C for (30 ± 5) min.Allow to cool in a desiccator. Weigh the flask and sample. Use a scalpel or other appropriate cutting utensils to cuta representative portion from the sample into small pieces ( 5 mm ∅ ). Weigh accurately (2 ± 0,2) g of the piecesinto a Soxhlet thimble and add cotton wool to the top of the thimble.Add approximately (50 ± 10) ml of diethyl ether into the flask. Reflux gently for 6 h ± 30 min. Allow sufficient time forthe diethyl ether to cool. Completely evaporate the diethyl ether by means of a steam bath. Place the flask in anoven at (105 ± 5) °C for (30 ± 5) min. Allow to cool in a desiccator and weigh. Repeat the drying and cooling cyclesuntil the difference between two consecutive weighings are not more than 0,0005 g. A blank solution shall be runconsecutively.