| 摘要 |
PURPOSE:To use a pseudo reference electrode and to considerably decrease the generation of noise in a sensor by providing an electrode of <=200KOMEGA impedance provided in a manner as to contact with a sample to be measured into a flow passage for the sample to be measured. CONSTITUTION:The concns. of respective ions can be calculated from the result of the measurement of the potential difference between a flow type ion sensor body 1 and Na<+>, K<+> and Cl<-> sensors. The Ca<2+> ion selective electrode which is the reference electrode has an ion selective film of a high impedance and the Na<+>, K<+> sensors, etc. are also electrically connected to a measuring system including a preamplifier, etc. via the high-impedance film and therefore the large noise intrude in the measured potential difference if the potential difference between the reference electrode and the ion sensors is directly measured. The electrode having <=200KOMEGA impedance is thereupon used within the ion sensor body and the respective potential differences between the electrode having the low impedance and the ion selective electrodes, by which the difference in the potential between both is determined. The liuqid to be measured is thereby grounded and the noise is decreased. |
