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The theoretical open circuit voltage (OCV) of solid oxide fuel cells (SOFCs) fed with carbon-based fuels and the amount of deposited carbon on the anode were calculated by the minimum Gibbs free energy method. The OCV values of Ni-YSZ Ⅱ YSZ LI LSM anode-supported cells using methane-based fuels were experimentally measured. The resuks indicate that the amount of deposited carbon decreases from the C-comer of the C-H-0 diagram to the carbon deposition boundary at a constant rate. In the case that most of deposited carbon is electrochemically oxidized, feeding fuels with high C:H ratio can enhance the value of OCV; Conversely, fuels with low C:H ratio are suggested. Theoretical analysis shows the rapidly decreasing value of OCV near the OCV boundary (OCV=0 V). Experimental results also reveal that the value of OCV dramatically decreases when the volume fraction of CO2 in fuel gas increases to be higher than 80%. These results imply that the compositions of carbon-based fuels should be near the carbon deposition boundary in the C-H-0 diagram, which is beneficial to suppress carbon deposition without significant OCV reduction. A relatively high value of OCV can be obtained at the H-corner in the non-carbon-deposition zone near the carbon deposition boundary, and the sequence of the value of OCV is CH4 > H2 > CO in the CO2-diluted ambiance at 600 ℃. Furthermore, the value of OCV cannot be significantly elevated via raising the proportion of external reforming or decreasing the temperature.

The diffusion couple was used to study solid state reaction in the FexO-TiO2 system at a temperature range of 1323 to 1473 K,during which the oxygen partial pressure was controlled by CO-CO2 gas mixture. The cross-sections of the diffusion couple were observed by electron probe microanalysis(EPMA),and the diffusion concentration profiles of Fe2+,Ti4+,and O2- ions were also determined. In combination with the phase diagram of the Fe O-TiO2 system,it was found that ulvospinel,ilmenite,pseudobrookite phases formed during the reaction and their growth was diffusion-controlled. According to the concentration changes of diffusion ions,the diffusion path of Fe ions was plotted,based on which the solid state reaction mechanism of this system was reasonably proposed.

The reduction behavior of zinc ferrite, an important constituent of zinc-bearing metallurgical dust, with CO-CO2 gas was calculated and analyzed according to the thermodynamic principles. The reduction of ZnFe2O4 obeys a stepwise mechanism. ZnFe2O4 is easy to be reduced to ZnO and Fe3O4. ZnO is easier to be reduced than FeO, and a lower volume fraction of CO gas is needed to reduce ZnO at a higher temperature. If the reaction temperature increases from 1100 K to 1400 K, the reducing potential expressed by the volume fraction of CO decreases from 0.4 to 0.01. Aiming to the reduction and separation of metallic zinc from zincbearing dust, it is not necessary to reduce iron oxides to metallic iron, but Fe3O4 or FeO, while zinc oxide should be reduced to metallic zinc. In the upper of the blast furnace, zinc reduction and internal circulation occur and bring harms to blast furnace production, and therefore the zinc load of the blast furnace should be reduced and controlled strictly.

The oxidation kinetics of iron sheet in CO2 -CO mixture was studied by on-line measuring the composition change of the reaction gas using a gas mass spectrometer under different CO2 partial pressures in the temperature range of 1273 to 1473 K. It is found that the oxidation rate increases linearly with CO2 paltial pressure, the rate constant decreases with the increase of COJCO volume ratio, and the apparent activation energy of the oxidation of iron sheet is (137.7±15.8)k J·mol-1. Compared with the results reported, this on-line mass spectrometry analysis can get reliable resuhs, so it can be used to study the gas-solid reaction kinetics.

The isothermal hydrogen reduction kinetics of FeO powder at 773-1273 K was investigated by thermogravimetry. Above 873 K, there was a turning point in the kinetic curve, which indicated that the reduction mechanism changed. An unusual temperature effect that the reduction rate decreased with increasing temperature was observed from 973 K to 1073 K. To discuss the effect of product structure on the reduction rate of iron oxide, the morphology of samples reduced at different temperatures and for different reaction time was observed by scanning electron microscopy. It was shown that holes on the sample surface increased gradually, the dendritic characteristic appeared with increasing temperature, and the sintered phenomenon was obvious at 973 K and 1023 K. At a certain temperature, holes on the sample surface increased and the sintered phenomenon appeared gradually with prolonging reaction time. At 973 K and 1023 K, the sample kept fairly the original shape, but at 1173 K, just reacted for 2 rain, a large number of dendritic products appeared and sintered gradually. Combining the morphology and kinetic curves, it can be summarized that interfacial chemical reaction is the rate-limiting step in the initial stage of hydrogen reduction. But as the reaction proceeds, the reduced iron sinters and the compact structure of the reduced product hinders the outward diffusion of produced gas. The rate-limiting step changes to the outward diffusion of produced gas, which leads to the decrease of the reduction rate of iron oxide by hydrogen.

It is a practical strategy to screen for mutants in the research of plant functional genomics. Comparing with classical T-DNA knock-out mutagenesis technology by the loss-of-function mutation, the activation T-DNA tagging technique based on the gain-of-function mutation has its own particular advantages, mainly characterized by producing dominant mutants of genes with functional redundancy and easily cloning of the genes. First, the basic principle of activation tagging, and the progress of its application in the research on plant functional genomics was reviewed, especially in Arabidopsis and rice. The recent research progress in the mechanism of plant biotic and abiotic stress tolerance and of plant development unraveled by the method of activation tagging was then addressed. Finally, the limitation and prospects of this technique were discussed.