掩蔽作用的原理在分析化学的各个领域已获得了广泛的应用,尤以在螯合滴定法中为最突出。就化学试剂的质量控制言,螯合滴定法是测定无机盐类含量的主要分析方法。Ringbom指出,所谓掩蔽作用乃是一种降低条件稳定常数(或作表观稳定常数,也可称作有效稳定常数)的方法。此一定义无疑是正确的,但并不全面。这是仅从热力学的角度加以考察所得的结论,排除了动力学掩蔽法。故此定义似可修改如下:所谓掩蔽作用乃是分析过程中的一种防止干扰反应的措施,而不需借助 The principle of masking has been widely used in all fields of analytical chemistry, especially in chelation titration. In terms of the quality control of chemical reagents, chelation titration is the main method for the determination of inorganic salts. Ringbom pointed out that the so-called masking effect is a way to lower the stability constant (or apparent stability constant, also called the effective stability constant). This definition is undoubtedly correct, but not comprehensive. This is a conclusion drawn from the thermodynamic point of view only and excludes the kinetic masking method. Therefore, the definition may seem to be amended as follows: The so-called masking effect is a measure to prevent interference in the analysis without resorting to