A new and distinct variety of peach tree. Pressure and displacement sensors normally provided with a positioner are used to detect operating parameters of the control loop. A piston means is provided in the mixing space of the mixing container. Therefore, after the control to suppress catalyst odor has ended, a smooth shift can be made into control to suppress degradation of the exhaust gas control catalyst. The solid oxide fuel cell includes: an anode layer, a cathode layer, and an electrolyte layer interposed between the anode layer and the cathode layer, wherein the anode layer includes: a conductive material; yttria stabilized zirconia ; and an oxide compound for forming a solid solution with the yttria stabilized zirconia. The magnesium thiosulfate solution can be prepared with concentrations of at least about 25%, preferably at least about 30%.