A novel solid oxide fuel cell (SOFC) system, which does not need to separate the supply of fuel and oxidant gases and generates electric power as well as chemicals, was studied. The fuel cell consisted of normalPt|BaCe0.8Y0.2O3−α|normalAu , in which two electrodes were exposed to the same mixture of CH4 and air. Electromotive forces (EMFs) were about 700∼800 normalmV at operating temperatures between 750 and 950°C, and terminal voltages were about 420 mV with discharge a current density of about 400 mA cm−2 (0.17 W cm−2) at 950°C and 350 mV with 75 mA cm−2 (0.03 W cm−2) at 750°C. The working mechanism of the fuel cell was clarified to be based on the difference in catalytic activity for the partial oxidation of methane between two electrode materials: the Pt catalyzes the partial oxidation of methane to form hydrogen and carbon monoxide, while the Au is inactive to this reaction. Therefore, the Pt acts as a fuel electrode, while the Au acts as an oxygen electrode at which electrochemical reduction of oxygen takes place on discharging the cell.

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In order to improve the performance of a cathode in a new solid oxide fuel cell (one chamber with methane-air mixture), a surface-modified yttria-stabilized zirconia (YSZ) with praseodymium oxide was tested as a solid electrolyte of this cell. The cell gave a stable open-circuit voltage of about 700 mV at 1223 K, and the maximum electric power density was about 60 times higher than that using "bare" YSZ. The difference in cell performance between bare YSZ and surface-modified YSZ is discussed in relation to the transient cathode potential at open circuit and the cathodic polarization during discharge.

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Sago palm (Metroxylon sagu Rottb.) photosynthetic performance was evaluated under drought conditions through leaf gas exchange and chlorophyll a fluorescence measurement. Drought has an impact on sago palm's leaf gas exchange parameters and its chlorophyll fluorescence of PSII. Stomatal limitations were found to be the main factor limiting photosynthetic activities of sago palm under drought conditions. Photosynthetic rate decreased following the inhibition in the PSII reaction center. Early detection of interference upon the efficiency of the PSII reaction center due to drought stress was recorded by chlorophyll a fluorescence measurement.Abbreviations: CF/I-light response curve of chlorophyll a fluorescence, C i -intercellular CO concentration, E-transpiration rate, E opt -optimum irradiance, ETR-electron transport rate, ETR maxmaximum electron transport rate, g s -stomatal conductance, I max -maximum irradiance, NPQnon-photochemical quenching, P N -net photosynthetic rate, P N /I-light response curve of net photosynthetic rate, P N (Imax) -maximum value of P N obtained at maximum irradiance, WUEwater use efficiency, Y (II)-effective quantum yield of PSII, α-asymptotic photosynthetic efficiency, Φ (Icomp-I200) -quantum yield at the range between light compensation point and 200 µmol m −2 s −1 irradiance.