Method and device for determining the hydrogen ion concentration by means of interface electrodes
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Device for measuring the hydrogen ion concentration
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Method for measuring electrical voltages using the compensation method
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Method for measuring resistance by means of voltage compensation with the aid of barrier photocells
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Method for measuring electrical voltages using the compensation method
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Device for conductivity and capacitance measurement with alternating current according to the differential method
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Tube voltmeter with alternating current connection for measuring static, stationary and slowly changing potential differences over time
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Method for measuring the hydrogen ion concentration with the aid of electrodes made of antimony, tungsten or other metals or their alloys that can be oxidized by dissolved oxygen
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Reference immersion electrode for electrometric measurements
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Device for keeping constant the reference or zero point setting on the measuring instrument of electron tube voltmeters in compensation circuit
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Translucent tool for colorimetric and other analytical determinations
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Aid for the colorimetric determination of dissolved chemical compounds
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Procedure for offsetting the measuring range of a tube voltmeter
