Dissolving zirconia electrode

Figure 2/6-6. Dissolving zirconia electrode. (1) Zirconia bridge between (2) Pt,02 reference electrode and (3) melt (4) alumina electrode shaft (5) alumina bolt (6) zirconia grit (7) thermocouple (8) four-bore alumina tube (9) electrode head. T, reference electrode temperature temperature of measuring electrode in isothermal melt with T, .

Figure 26-13. Arrangement of cells for measuring oxygen fugacities in a streaming nonisothermal melt by referring to only one nonisothermal dissolving zirconia reference electrode (see Equation 26-35). E, and = measured emfs Th = thermocouples measuring indicated temperatures = temperature of reference electrode = temperature at contact ZrO/melt , and T 2 temperatures of platinum measuring electrodes.

Okimura, T., Fukui, K. and Maruhashi, S. (1990) Development of zirconia electrolyte sensor with auxiliary electrode for the in situ measurement of dissolved silicon in molten iron. Sens. Actuators B, 1, 203-9. 

The results of the present work may be applicable for diagnostics of oxygen sensors at more complicated applications, such as measurement of oxygen activity in liquid sodium, lithium, or lead-bismuth heat carriers for atomic power plants. Corrosion and mass transfer in nonisothermal lead-bismuth circuits with temperatures of a heat carrier of 300-500°C do usually occur at a concentration of dissolved O2 of 10 - 10 mass %. The proposed impedance method is developed for determining the level and the character of polarization at the electrolyte-electrode interface, which ensures a continuous oxide protection of materials against corrosion by means of zirconia sensors in all tanperature regimes of exploitation of liquid-metal circuits. 

We have developed nanoparticle label-based electrochemical immunoassay of OP exposure biomarkers, OP-ChE (44). The principle and procedure of this method is shown in Figure 5. Here, zircomia (Zr02) NPs, electrochemically deposited on the electrode surface, which functioned as the capture antibodies in the sandwich immunoassay. The zirconia- NP- modified electrode is then exposed to the sample solution and the ChE-OP in the sample is captured by the Zr02 nanoparticles. The QD-tagged, anti-AChE conjugate is introduced to form the sandwich-like complex on the sensor surface. The captured QDs are then dissolved by a drop of acid to release cadmium ions. This is followed by square wave voltammetric (SWV) [abbreviation already introduced but unexplained] detection of the released cadmium ions at an in situ plated mercury/bismuth film electrode. 

Gas dissolved in blood. Composite electrode (oxygen Zirconia film/02 etc., CO2 Diagnosis and cure ... 

Fabry and Kleitz used cyclic voltammetry to study the behaviour of copper dissolved in zirconia in the temperature range of 1000 - 1200 K. More recently, van Manen and co-workers have used cyclic voltammetry between 700 and 900°C to investigate the behaviour of a number of metal/metal oxide systems consisting of Fe/Fc203, Ni/NiO, Cu/CuO, C0/C02O3. Ni/NiO was used as the reference electrode. All electrodes were prepared as tablets from physical mixtures of metal and metal oxide. All of the systems were found to be irreversible. Peaks in the cyclic voltammogrammes were ascribed to formation of oxide and metal layers which acted as diffusional barriers at the surface of the electrodes. 

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