Absorption spectroscopy Acetone Activated carbon Anodes Arsenic Arsenic speciation Atomic absorption spectrometry COMBUSTION Catalysts Ceria Ceria-based anodes Cerium compounds Combustion Coupled circuits Crystallography Degradation Direct combustion ETAAS Electronic conductivity Knotted reactor Knotted reactors Medicinal herb Methane Performance degradation SOFC Solid catalysts Solid oxide fuel cell Solid oxide fuel cells Tea Zirconia