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The thermomagnetic oxygen analyzer operates on the principle of utilizing the high magnetic susceptibility of oxygen in the components of flue gas to determine the oxygen content in that flue gas. Oxygen is a paramagnetic gas (a gas that is attracted by magnetic fields is called a paramagnetic gas); it is drawn toward areas with stronger magnetic fields in an uneven magnetic field. A heating wire is installed there, which raises the temperature of the oxygen in that area and reduces its magnetic susceptibility; as a result, the magnetic attraction decreases. The oxygen molecules that are not heated and have a higher magnetic susceptibility push against these molecules, causing them to be expelled from the magnetic field. This gives rise to the phenomenon of \"thermo-magnetic convection\" or \"magnetic wind\". Under certain gas sample pressure, temperature, and flow rates, the oxygen content in the gas sample can be determined by measuring the magnitude of the magnetic wind. Since the thermosensitive element (platinum wire) serves both as the resistances of the two bridge arms of the unbalanced bridge and as a heating wire, a temperature gradient is created under the effect of the magnetic wind; that is, the temperature of the bridge arm on the intake side is lower than that of the bridge arm on the exhaust side. The unbalanced bridge will output a corresponding voltage value depending on the oxygen content in the gas sample. Although thermomagnetic oxygen analyzers have advantages such as simple structure, ease of manufacturing, and adjustment, they have been gradually replaced by zirconia oxygen analyzers due to their shortcomings including slow reaction speed, large measurement errors, susceptibility to blockage in the measurement chamber, and severe corrosion of the thermosensitive elements.