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In order to investigate the role of Al on the thermal stability of supercooled liquid state, the local structures of Zr 70 M 30 and Zr 70 M 20 Al 10 (M ¼ Ni, Cu) metallic glasses have been studied by the X-ray diffraction and EXAFS measurements. It is found that the different effect of Al substitution on the local structures around Cu and Ni elements is exhibited. No characteristic change is observed in the local structure in the ZrCu metallic glass by Al substitution, whereas a drastic change in the environment around Ni atom can be confirmed in the Zr-Ni metallic glass. That is, the coordination number of Zr around Ni decreases significantly by substitution of Al in the Zr-Ni metallic glass. This would be caused by the preferential correlation between Al and Zr. This result suggests that Al plays a dominant role on the formation of novel local structure with a decomposition of the tetragonal Zr 2 Ni-like local environment in the Zr-Ni binary alloy. We conclude that the novel local structure contributes to the stability of the supercooled liquid state in the Zr-Al-Ni metallic glass.

Nb 2 O 5 -WO x synthesized by a hydrothermal method having a long nano-crystalline structure with ca. 10 nm diameter exhibited a high catalytic activity in the Friedel-Crafts alkylations and acylations when it was calcined in N 2 .

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