气相色谱保留指数通用数据库的研究（三）不同柱温模式下保留指数的相互转换

Studies on Universal Database of Gas Chromatography Retention Index Ⅲ.Conversion of Retention Index Under Different Column Temperature Conditions

由于升温模式（Ｔ_０，ｒ）、色谱柱和操作参数（Ａ，Ｔ_ｂ，β）的差别，使得Ｔ_Ｒ不同而影响Ｉ_（ＴＰ）的可比性，其影响的大小随恒温保留指数ＲＩ的温度系数的增加而增加。同时，由于Ｔ_Ｒ与ｎ偏离了线性关系，采用保留温度线性插值方法计算Ｉ_（ＴＰ），方法本身就在一定程度上会使Ｉ_（ＴＰ）的可比性差，即使恒温ＲＩ的温度系数为零，Ｉ_（ＴＰ）也会随ＧＣ条件而改变。根据恒温与线性程升的保留值方程建立的各种柱温模式下的保留指数相互转换方法能准确快速地预测不同柱温模式下的保留指数，以此来建立通用数据库以适应不同的分析条件的需要，特别是从２种升温模式出发预测其它柱温模式下的保留值能更方便地对复杂样品的分离条件进行优化。

Retention index in TPGC I_(TP) is often affected by the mode of temperature programming and other parameters including pressure and the nature of carrier gas, size of column and its phase ratio. Generally,the greater the temperature coefficient of RI(△I/△T)is, the more diversified the I_(TP) will be. At the same time,the I_(TP) calculated according to ven den Dool’s definition will be of poor comparability since retention temp. TR and carbon number n of n-alkanes is not linearly correlated, especially when high initial col. temp.,short dead time and small rate of temperature programming are adopted. Due to the reason mentioned above, ITP is usually influenced by operating conditions in TPGC even in case △I/△T is equal to zero. The method proposed in this paper for the conversion of retention index from each other under the different col. temp. Modes and carrier gas conditions is of great importance in establishment of a universal retention index database to be applied under different GC conditions, particulary, in the optimization of GC conditions for the separation of complex mixtures based on the correct data available.