| 摘要 |
PURPOSE: To obtain a sensor in which stability and activity are sustained for a long term while shortening the settling time by arranging anode and cathode concentrically in adjacent to an opening communicating between the outside of body and an electrolyte container. CONSTITUTION: An opening 16 is made to communicate between a container 14 and the outside of a body 12 containing an electrolyte container 14 and the opening 16 is sealed with a polymer diaphragm 18 impermeable to the electrolyte. Anode 22 and cathode 24 having working surfaces spaced apart from the diaphragm 18 are formed contiguously to the diaphragm 18 sealing the opening 16 while defining a space for containing the electrolyte with respect to the diaphragm. Furthermore, a noble metal screen 48 is provided on the working surface of anode 22 in order to sustain a high ratio of area (at least about 85:1) between anode and cathode over one interval and temperature range while minimizing the activity loss of electrode. The noble metal screen 48 is made of platinum or an alloy thereof and has 50-1000 mesh. |
