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A series of 3DOM cerium-based perovskite catalysts with different B-site elements were prepared by the colloidal crystal template method and excess impregnation method with Cr, Ni, and Mn as the B-site elements. The physical and chemical properties of the catalysts were investigated by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), hydrogen temperature-programmed reduction (H2-TPR), and oxygen temperature-programmed desorption (O2-TPD) characterization techniques. The results showed that the catalyst with Mn as the B-site element had a high-quality macropore structure (pore size 200–250 nm), large specific surface area (45.26 m2/g), and abundant surface adsorbed oxygen content (Oads/Olatt = 0.46). The addition of manganese enhanced the low-temperature reducibility, and the main reduction peak was below 400 °C. The O2-TPD results showed that 3DOM CeMnO3 expressed the highest adsorption oxygen content. The 3DOM CeMnO3 possessed the best catalytic performance with T 50% = 102 °C and T 90% = 203 °C during the catalytic oxidation of toluene. Intermediate product study hinted that toluene was first converted into benzoic acid and benzaldehyde and then further degraded into small molecules. The catalyst with the best activity also exhibited good stability, and toluene degradation rate remained above 85% at 200°C for more than 20 h of continuous experiments.

Pultruded fibre reinforced composite (PFRC) can be used in oil drilling because of the corrosion resistance and energy conservation. The studies of fatigue behaviour and life distribution model are essential to the design and application of PFRC. In this paper, the tensile fatigue behaviour of PFRC was studied by the experiment combining with the acoustic emission technology, and the fatigue life distribution model is established to explore the distribution characteristics of fatigue life. The results show that, the fatigue load level has little effect on the failure modes of PFRC, and the matrix damage occurred firstly followed by the appearance of the delamination and the fibre damage. The proposed fatigue life distribution model can accurately describe the three stages of the fatigue life curve, and can well predict the fatigue life under different survival rates.

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