A Ni/Mo 2 C/SBA-15 catalyst was prepared for carbon dioxide reforming of methane to produce synthesis gas. The catalysts modified by nickel were prepared from ammonium heptamolybdate that was supported with SBA-15 and were carburized in a flow of 20.0 vol% CH 4 /H 2 gas mixture. The catalyst was characterized by N2 adsorption, X-ray diffraction, and scanning electron microscopy analysis. The activity and stability of the catalysts for dry reforming of methane was tested at 1073 K, atmospheric pressure, gaseous hourly space velocity of 8,000 ml 3 h 1 g 1 , and a CH 4 /CO 2 molar ratio of 1. The Ni/Mo 2 C/SBA-15 catalyst exhibited a better catalytic and anti-coking performance due to smaller metal particles, higher metal dispersion, and better ordered pore distribution compared with Mo 2 C catalysts. The surface carbon of nickel migrated to molybdenum carbide, which prevented the oxidation of molybdenum carbide and coke deposition.

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The effect of Al-5Ti-1B grain refiner addition on solidification microstructure, especially the formation of the binary eutectic (Al)+Al15(Fe,Mn)3Si2was investigated in Al-5Mg-2Si-0.7Mn-1.1Fe (wt.%) alloy. The experimental results showed that the solidification microstructure were consisted of primary α-Al phase, inter dendritic binary eutectic (Al)+Al15(Fe,Mn)3Si2, and ternary eutectic (Al+Mg2Si+Al15(Fe,Mn)3Si2). The heterogeneous nucleation of the primary (Al) phase in the alloys was greatly enhanced by the Al-5Ti-1B grain refiner, refining the (Al) grains significantly. The subsequent binary eutectic was nucleated on these refined (Al) phase. Consequently, the size of Al15(Fe,Mn)3Si2phase with a Chinese script morphology in the binary eutectic was greatly refined, without much change in the secondary branch spacing.

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