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Ni/La 2 O 3 with a high dispersion was prepared by reduction of LaNiO 3 perovskite oxide to examine the catalytic activity for the CO 2 -CH 4 reaction. The Ni/La 2 O 3 catalyst was found to be highly active for the reaction. The ratios of H 2 /CO were measured in a flow of the reaction mixture containing CO 2 /CH 4 /Ar using an on-line gas chromatography system operated at 1 atm and found to be varied with temperature between 0.66 and 1 in the temperature range of 500-800 o C. A kinetic study of the catalytic reaction was performed in a static reactor at 40 Torr total pressure of CO 2 /CH 4 /N 2 by using a photoacoustic spectroscopy technique. The CO 2 photoacoustic signal varying with the concentration of CO 2 during the catalytic reaction was recorded as a function of time. o C under various partial pressures of CO 2 and CH 4 , the reaction orders were determined to be 0.43 with respect to CO 2 and 0.33 with respect to CH 4 . The kinetic results were compared with those reported previously and used to infer a reaction mechanism for the Ni/La 2 O 3 -catalyzed CO 2 -CH 4 reaction.

Highly transparent ($90% in the visible region) indium gallium zinc oxide (IGZO) thin films were deposited using a spin coating process with a newly developed precursor solution. Acetonitrile was used as the solvent in the preparation of the metal halide precursor solution for the deposition of the IGZO thin films. Ethylene glycol was added to the solvent at four different volume ratios of acetonitrile to ethylene glycol to complement the chemical properties of acetonitrile in order to avoid the de-wetting phenomenon during the deposition process. The IGZO thin films were prepared at a stoichiometric molar ratio of 2:2:1 on the basis of the theoretical In 2 O 3 -Ga 2 O 3 -ZnO structure. The IGZO metal-oxide-semiconductor field-effect transistor (MOSFET), with a field-effect mobility (m FE ) as high as 1.1 cm 2 =V s, a turn on voltage of 15.8 V, and a current on-to-off ratio greater than 10 7 , was successfully fabricated in this study. This low cost solution-based deposition process was applicable for the fabrication of transparent conducting oxide (TCO)-based devices.

Ni/CeO2 catalysts with different Ni loadings (5, 7, 10, 12, and 14 wt% Ni) were prepared by an impregnation method and examined for the CO2 reforming of methane using flow and static reactors. Their catalytic activities and selectivities were measured under CO2/CH4/Ar (=5/5/40 cm3/min) flow at 450–800°C using a flow reactor system with an on‐line gas chromatography. At fixed temperature, the CO2 and CH4 conversions varied only slightly with the Ni wt%, whereas the H2/CO ratio increased with increasing Ni wt%. The conversions increased with temperature, reaching 98% at 800°C. The H2/CO ratio varied with temperature in the range of 450–800°C, from less than 1 below 550°C to close to 1 at 550–600°C and then back to less than 1 above 600°C. The apparent activation energies were determined to be 43.1 kJ/mol for the CO2 consumption and 50.2 kJ/mol for the CH4 consumption based on the rates measured for the reforming reaction over 5 wt% Ni/CeO2 catalyst at 550–750°C. Additionally, the catalytic reforming reaction at low pressure (40 Torr) was investigated by a static reactor system by using a differential photoacoustic cell, in which the rates were measured from the CO2 photoacoustic signal data at early reaction times over the temperature range of 460–610°C. Apparent activation energies of 25.5–30.1 kJ/mol were calculated from the CO2 disappearance rates. The CO2 adsorption on the Ni/CeO2 catalyst was investigated by the CO2 photoacoustic spectroscopy and Fourier transform infrared spectroscopy. Feasible side reactions during the catalytic CO2/CH4 reaction were suggested on the basis of the kinetic and spectroscopic results.