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本文应用统计力学中的系综理论,探讨了缓蚀剂在金属表面上的吸附过程遵守 Langmuir 吸附等温式情形下的吸附热(q),和遵守 Temkin 吸附等温式情形下的吸附的缓蚀剂分子间相互作用能(U)。推导出了缓蚀剂的吸附热(q)表示式,并利用该式从微观方面对缓蚀剂的吸附热进行了解释。推导了吸附的缓蚀剂分子间相互作用能(U)表示式,并从该式定义了一个能定量描述吸附的缓蚀剂分子间相互作用的常数。此外还提出了从缓蚀效率的实验数据分刖求算 q 和 U 值的方法,并用这个方法从文献上的有关实验数据求算一些缓蚀剂的 q 和 U 的值。最后从计算结果分别总结出缓蚀剂的吸附热(q)及吸附的缓蚀剂分子间相互作用能(U)与缓蚀剂的性能之间的关系,并将这个结论和从能量方而考虑得到的结论进行了比较。

The heat of adsorption for corrosion inhibitors obeying Langmuir isotherm,and the energy of lateral interaction between the adsorbed molecules for corrosion inhibitors obeying Temkin isotherm were ten- tatively treated with the ensemble theory in statistical mechanics.Based on Langmuir's theory,the expression of adsorption heat(q)for inhibitor was derived,which,revealed the relationship between adsorption heat and the microscopic properties of the adsorbed inhibitor molecules,as well as temperature.Based on the model set up for adsorption system,the expres- sion of moar at rr craction energ between the adsorbed inhibitor molecules was derived,from wich the constant of interaction was defined for the quantitative description of the lateral interaction between the adsorbed inhibitor molecules.The methods of evaluating the values of q andfrom the experimental data of inhibition efficiency were also presented respectively.By treating the experimental data of inhibition efficiency from literature with these methods,the values of q andwere evaluated for some corrosion inhibitors.The evaluated results revealed that for some corrosion iahibitors with simllar nature or structure,the larger the value of q is.the better the perfermance of inhibitor becomes; the smaller the value ofis,the better the performance of inhibitor becomes,which are in agreement with the conclusion drawn from the viewpoint of energy.