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Gold nanoparticles supported on halloysite nanotubes (Au/HNTs) were prepared by a homogeneous deposition-precipitation method. The specific characteristics of the catalyst were characterized in detail, in relation to their performance for solvent-free oxidation of benzyl alcohol. The particular structure of the catalyst resulted in high catalytic activity and stability compared with other supported gold catalysts. The enhanced catalytic activity of the Au/HNTs catalyst was mainly attributed to the presence of a higher amount of oxidized gold species and the tubular structure of the HNTs.

Asphalt mixture is a typical visco-elastic material whose dynamic response has a strong relationship to the test conditions of temperature and loading frequency. To study the dynamic response of asphalt mixture, simple performance test (SPTs) were conducted on three asphalt mixtures for different gradations and binders. The effect of test temperature and loading frequency on dynamic modulus (E*) and phase angle (δ) of asphalt mixtures are investigated. On the basis of discussing the shift factors of dynamic modulus and phase angle, a master curve is obtained. The results indicate the dynamic modulus of asphalt mixtures decreases with either an increase in temperature or a decrease in loading frequency, and the relative shift with decreasing load frequencies becomes less and less. The peak temperature of the phase angle for different loading frequencies is not the same. The dynamic modulus master curve and shift factor can reflect the effect of loading frequency and temperature on material properties, as well as describe fully the visco-elastic properties of asphalt mixture.

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