| 摘要 |
896,575. Determining relative quantities of fluid mixture constituents. BECKMAN INSTRUMENTS Inc. Jan. 19, 1961 [Jan. 25, 1960], No. 2139/61. Class 37. In a fluid analysis cell comprising an electrode 17 and a membrane 27 enclosing with surface 26 of the electrode a film of electrolyte, the membrane is permeable to the component it is desired to measure but impermeable to the electrolyte, and inlet tube 24, and outlets 30 are provided to the space occupied by the film, so that the film can be renewed as desired. The supply of fresh electrolyte is housed in a vessel 13 including a reference half-cell 14, and may be forced through the tube 24 by a rubber bulb 15, or by gravity, a clamp 22 providing for pressure regulation or flow control in the latter case. Test current is taken from a screwed metal top cap 19 on chamber 10 which carries the electrode, connection being made by an embedded wire 18. The membrane 27 is clamped by a resilient ring 28. In a modification described with reference to Figs. 4-6 (not shown), an annular groove is provided in the outer wall of chamber 10 under the membrane, which groove serves as an outlet manifold connecting with three outlet passages, and a sleeve is provided which may be slid down the chamber wall to cover the outlet orifices whilst a reading is being taken. Use of the apparatus to determine the carbon dioxide content of a fluid is referred to, the membrane material then being natural rubber, polyethylene, vinyl chloride or silicone rubber; the electrode being of platinum; and the electrolyte being a solution of quinhydrone and sodium bicarbonate. Specification 838,980 is referred to. |
