使色谱峰产生拖尾的一个因素--柱出口效应

摘　要：使用塔板理论证明存在一种使正常色谱峰产生拖尾的因素--柱出口效应。证明符合线性分配的样品组分虽然在色谱柱内存在3种不同浓度的分布形态，但在流出色谱柱后却都因柱出口效应的影响而转变成拖尾峰。在不加任何近似处理的情况下，使用塔板理论直接对不同塔板数、容量因子的色谱峰不对称性进行了计算；计算结果同样支持了柱出口效应的存在。

关键词：塔板理论，柱出口效应，拖尾峰

分类号：065　文献标识码：A

A Factor　for Causing Chromatographic Peak to Tail - -Effect of Column Outlet

Fan Guoliang（Analysis Center, Tianjin University, Tianjin 300072）　
Yan Ying（Analysis Center, Tianjin University, Tianjin 300072）　
Kang Kai（Analysis Center, Tianjin University, Tianjin 300072）　
Zhou Weiyi（Analysis Center, Tianjin University, Tianjin 300072）　
Jiang Dongfeng（Analysis Center, Tianjin University, Tianjin 300072）　
Song Chonglin?（National Engine Combustion Laboratory, Tianjin University, Tianjin 300 072）　

Abstract：A factor-effect of column outlet could cause normal chro matographic peak to tail when the solute left the end of the column was proved b y plate theory. When the distribution coefficient was constant and independent of the amount of solute present in a plate, the distribution of solute could have three shapes in the column, but they all turned to skewed peaks when leaving the end of the column. The last plate makes the solute change their shapes to skewn ess when they left the end of the column; this factor was named the “effect of column outlet”. The asymmetry of solute inside or outside of the column was cal culated by using dircetly plate theory under the different number of plate n and partition ratio k′, A％＝（A_b－A_f)/［(A_b＋A_f )/₂ ］ (A_b=back area and A_f=front area of the peak, measured from a ver tival line through the base line), the A％ proved to have the effect of co lumn outlet again. The effect of column outlet could be eliminated with temperat ure program in gas chromatography and elution gradient in liquid chromatography, using these methods could reduce the k′ in the last plate, therefore the n ear symmetrical peak could be obtained when use these methods.
Keywords：Plate theory, effect of column outlet, skewed peak

参考文献：

［1］Lu Peizhang(卢佩章), Dai Chaozheng(戴朝政), Zhang Xi angmin(张祥民). Base of Chromatography Theory(色谱理论基础). Beijing(北京): Science Press(科学出版社), 1997：44～129
［2］Dai Chaozheng(戴朝政), Xiang Zaijun(向在筠). Acta Chimica Sinica(化学学报),1994, 52:64～70
［3］Dal Nogare S, Juvet R S. Gas-Liquid Chromatography Theory and Prac tice. New York:Interscience Publishers, 1962:60～61
［4］Wang Dongyuan(王东援), Sun Yuqing(孙毓庆), Wang Yanzong(王延琮). C hinese J . Chromatography(色谱), 1993, 11:120～121

收稿日期：2000年7月3日

修稿日期：2000年1月18日

出版日期：2001年6月1日