The ion density measurement manner null in the automated study

摘要

PURPOSE:To suppress measuring errors due to a temperature change, by shifting an iso-thermal intersection of an ion selective electrode near a measuring ion concn. CONSTITUTION:The position of an ion-thermal intersection (a) of an ion selective electrode (e.g. clad film type electrode) as such in a graph in terms of temperature with a different output electromotive force for ion concn. is shifted near a mean of a measuring ion concn. by selecting one or both of the number of stages of a sensitive film layer and hardness of each layer surface. Thus, the ion selective electrode itself is made hard to be affected by temperature thereby minimizing measuring errors due to a temperature change without use of a thermostatic device and temperature corrector.