以因次化郵包模型模擬層析管分離作用之研究

Abstract

本研究以郵包模型(Parcel model)和空時扭變高斯方程式(Temporally Convoluted Gaussian Equation,簡稱TCG)為基礎，推導一個可適用於 流動注入分析及層析法的波峰方程式，並利用交大的實驗數據佐證之。在原理上，將無因次滯留效應(retention effect)因次化，再與沿散效應（dispersion effect）一起併入TCG方程式的標準偏差項中。結果發現，本研究推導之波峰方程式不但可以模擬層析譜，還可以預測不同實驗條件下之波形，更進一步證明層析管柱中沿散效應極小。其中對於樣本在管柱中擴散的描述，與著名范丁特方程式(van Deemter equation)，有異曲同工之妙。

A continuous Parcel model has been established by incorporating a recently developed discrete Parcel concept with Fick’s Law. The band broadening of an injected sample is assumed attributing to three major factors namely, the initial state, the retention effect and the dispersion effect. An Excel worksheet has been designed to simulate the sample migration route and peak shapes on both longitudinal and temporal axes. The model was applied to analyze experimental data provided by a research group of National Chiao Tung University. The results of peak restoration were found satisfactory. It was also found that the dispersion coefficient (D) is minimal in a chromatographic column, and that the peak shape is mainly controlled by the distribution ratio k” and a parameter (Δt) representing the efficiency of the column system of interest. The mathematical expression for the height of the theoretical plate derived by the present model is very similar to the well-known van Deemter Equation.