摘要 |
The invention relates to an apparatus for measuring the concentration of gaseous hydrogen dissolved in a liquid substance. The apparatus comprises an electrochemical cell constituted of a polymeric membrane in contact with a sample of the liquid substance and which is permeable to hydrogen, of an electrolyte capable of causing an oxydation reaction of the hydrogen diffused through the polymeric membrane, at a first electrode, and a reduction reaction of an oxygenated gas at a second electrode, so as to deliver an electric current proportional to the hydrogen concentration to be measured. An electrovalve operates, when activated, to exhaust the liquid substance sample at a predetermined instant in the measuring process. Moreover, the circuit amplifies a voltage corresponding to the value of the current proportional to the concentration, which current flows through a load resistance mounted in parallel across the first and second electrodes and the input of the amplifying circuit. A display device is connected to the output of the amplifying circuit and supplies a digital measure of the hydrogen concentration in the liquid substance. A control unit determines the operation times of the electrochemical cell, of the electrovalve as well as of the digital display device pursuant to a predetermined sequence.
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