【摘要】 从理论上推导出了用柱相比和不用柱相比时溶质在反相高效液相色谱保留过程中的总熵变△S(Pa)的两个表达式,后者亦为计量置换保留模型中线性参数与该过程热力学函数间的定量表达式.△S(Pa)也能够被分成两个独立的分量,吸附墒变面△S(I,a)和解吸附熵变△S(Z,D).依据液相色谱中溶质计量置换保留模型中容量因子与流动相中置换剂活度a_D间的定量关系,对在不同a_D条件下溶质的总熵变、吸附及解吸附熵变进行了估算,并用实验测定的总熵变△S(Pa,e)与估算总熵变△S(Pa,c)进行了比较,获得了结果的一致性.本文对传统的“吸附伴随着熵减小,相反,解吸伴随着熵增大”的定性规律予以定量的说明.更多还原

【Abstract】 Two expressions of calculating entropy changes △S(Pa) solute either with,or without column phase ratio in reversed - phase liquid chromatography were theoretically derived. The latter is also an equation to express the quantitative relationship between some linear parameters in stoichiometric displacement model for retention (SDM- R) and the thermodynamic functions inthe same process. The △S(pa) .liking Gibbs free energy and enthalpy changes,can also be dividedinto two independent fractions, adsorption entropy change, △S(I,a) and desorption entropy△S(Z,D). Based on the quantitative relationship between the solute retention and the activity ofdisplacing agent in mobile phase described by the SDM-R, the △S(Pa), △S(I,a)and △S(Z,D) under various aD can be evaluated, respectively. The experimental and the evaluated results of entropy were obtained with a good agreement. The traditionally qualitative rule that adsorption of component is companied with the decrease in entropy, on a contrary, desorption is that with the increase in it can be quantitatively elucidated with the studies.更多还原