An electrolytic sensor is set forth for measuring the amounts of an ionic and of a vaporous species in a liquid. The system has an electrode sensitive to an ionic species and another electrode sensitive to a vaporous species. A unitary membrane covers the electrodes and the requisite electrolyte with...http://www.google.com.hk/patents/US5183549?utm_source=gb-gplus-share專利 US5183549 - Multi-analyte sensing electrolytic cell
