| 摘要 |
PURPOSE:To prevent bad effects upon an electrode by ions which are not the detection objects to prevent electrode deterioration and determine the halogen concentration stably for a long duration by immersing a detection electrode in an internal liquid and bringing the internal liquid into contact with the examination liquid through an anion exchange mambrane. CONSTITUTION:An internal liquid storage part 2a is filled with an internal solution 2b, a detection electrode 7 is installed so as to be brought into contact with the internal solution 2b, and a counter electrode 3 is set in the outside. The internal solution 2b is brought into contact with an examination liquid while having a diaphragm 4 made of an anionic ion exchange mambrane between them to prevent anions and reducing agnets harmful to the electrode 7 except halide ions from invading the internal solution 2b. The internal solution 2b contains halide salt, various of salty, e.g. Na2SO4, Na2CO3, as solution components and in the case the concentration of the halide ions is set to be (1/3)-(1/50) of that of the halogen in the examination liquid, the determination precision is improved. The less the amount of the internal solution 2b, the more quicker the solution components reach equilibrium state and the shorter the distance (e.g. <=1mm) between the electrode 7 and the diaphragm 4, the quicker the response of the electrode 7. |
