| 摘要 |
PURPOSE:To microminiaturize and miniaturize the sensor and to shorten the response time thereof by adopting the constitution consisting in mounting an electrode to an ion selection sensitive part and connecting an impedance analyzer to this electrode. CONSTITUTION:The sensor is constituted by mounting lead wires (silver wires having 0.3mm diameter) 2a, 2b to constitute an electrode pair in an ion selection sensitive film (selected to meet the noticed ion species to be measured) apart a prescribed spacing W (1mm) in parallel (20mm length of the parallel part) and connecting the wires 2a, 2b to the impedance analyzer 3. The capacity and resistance of the sensor change with the spacing W, the volume and shape of the sensitive film 1 and the geometrical factor of the joint state of the wires 2a, 2b. The capacity of the sensor is previously measured by immersing the sensor always at a specified depth D into several kinds of the solns. of a known concn. of the ions to be measured and different concn. levels and the calibration curve thereof is formed. The sensor is then immersed by the depth D into a sample soln. 4 and the capacity by the impression of AC is measured by the analyzer 3. The result of the measurement is collated with the calibration curve and the concn. is calculated. |
