| 摘要 |
PURPOSE:To enable handy measurement, by immersing an electrochemical cell as junction body or pressure-weld body in which a cathode and an anode are junctioned or pressure-welded on an ion exchange resin film, as covered with a water repelling resin film, into an aqueous solution. CONSTITUTION:An electrochemical cell has an ion exchange resin film 1 comprising a perfluorocarbon sulfonic acid resin film, a cathode 2 made of platinum, a cathode current collector 4 comprising expanded titanium, an anode current collector 5 comprising expanded titanium and a water repelling resin film 6 comprising a porous polytetrafluoroethylene film. This electrochemical cell (concentration sensor) is immersed into a sulfuric acid aqueous solution, adjusted in various concentrations, and when a DC constant voltage is applied between the cathode 2 and the anode 3, with the electrolysis of water absorbed by the resin film 1, current is generated in direct proportion to a steam pressure corresponding to the concentration of the solution. By detecting this current, the concentrations of solutes in the aqueous solution can be measured with a very small electrochemical cell with a very handy operation and continuously. |
