| 摘要 |
1,213,616. Electro-chemical analysis cells. INSTRUMENTATION LABORATORY Inc. Jan. 16, 1969 [Jan.24, 1968], No.2630/69. Heading G1N. In a system for measuring the amount of a constituent of a substance, a circulating carrier is used to transport the constituent along a path from a sampling point to a coulometric cell and a selectively permeable membrane through which the constituent can diffuse bounds a portion of said path at either the sampling point or the cell. As shown in Fig.2, an arrangement for measuring in vivo the oxygen content of blood comprises an oxygen-permeable silastic tube 112 for inserting into an artery and connected into a closed circulation loop including a pump 22 for circulating a saline electrolyte in the loop and a coulometric cell 20 for electro-chemically reducing all the oxygen diffusing through the tube 112 into the electrolyte. Cell constructions. The cell comprises a platinum cathode 88 for reducing the oxygen in the form of a helix wound on a porous glazed porcelain tube 92 and held in place by a shrinkable vinylidene fluoride sleeve 102 which also defines a helical flow path for the incoming electrolyte of such a length that all the oxygen is reduced. A silver anode 110 is disposed within the porcelain tube 92 and a silver reference electrode 28 is connected in a feedback circuit with the anode to maintain the cathode reference electrode voltage constant. A layer 106 of silicone rubber sealant covered by a second sleeve of vinylidene fluoride provides a fluid tight seal. In an alternative cell, Fig. 10 (not shown), a silver wool cathode (202) is disposed within a porcelain tube (200) surrounded by a coiled silver anode (210). In Fig.9, the selectively permeable membrane is at the cell and comprises a helix of oxygen permeable tubing 112' interleaved with a cathode helix 88' and is held in place on a porous ceramic cylinder 92' by an impermeable vinylidene fluoride sleeve 102'. For supervising fermentation processes, a biological filter (220) may be provided in addition to a selectively permeable silicone membrane (224), Fig. 15 (not shown). |
