Ce-MnO_x composite oxide catalysts with different proportions were prepared using the coprecipitation method, and the CO-removal ability of the catalysts with the tested temperature range of 60–140 °C was investigated systematically. The effect of Ce and Mn ratios on the catalytic oxidation performance of CO was investigated using X-ray diffraction (XRD), X-ray energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), H₂ temperature programmed reduction (H₂-TPR), CO-temperature programmed desorption (CO-TPD), and in situ infrared spectra. The experimental results reveal that under the same test conditions, the CO conversion rate of pure Mn₃O₄ reaches 95.4% at 170 °C. Additionally, at 140 °C, the Ce-MnO_x series composite oxide catalyst converts CO at a rate of over 96%, outperforming single-phase Mn₃O₄ in terms of catalytic performance. With the decrement in Ce content, the performance of Ce-MnO_x series composite oxide catalysts first increase and then decrease. The Ce MnO_x catalyst behaves best when Ce:Mn = 1:1, with a CO conversion rate of 99.96% at 140 °C and 91.98% at 100 °C.

Epoxy resin, known for its excellent corrosion resistance, water resistance, and high-temperature resistance, is extensively utilized in construction and water-related projects. Within water conservancy projects, natural factors such as water impact and weathering often result in cracks within rock formations. Consequently, the application of epoxy resin materials for repair and reinforcement has emerged as a common solution. This research investigates the impact of five epoxy grouting materials, YDS (100:6.4), RH-1 (6.1:1), PSI (9:1), TK (100:8), and HK-G (5:1), on the repair and reinforcement of faulted rock at the Yebatan Hydropower Station. Penetration experiments were conducted on rock samples, and the strength of the epoxy grout samples was tested under ambient conditions of 20 °C, 15 °C, and 0 °C. The experimental results indicate that all five epoxy grout materials successfully penetrated the faulted rock samples. Among them, the PSI (9:1) epoxy grouting material exhibited the most exceptional reinforcing effect across different temperatures, with grouting samples demonstrating strengths in the range of 20 to 25 MPa. This paper confirms that epoxy resin effectively repairs and reinforces rock structures, thereby enhancing the safety and durability of water conservancy projects.

Through an activation reaction sintering method, porous (Mo_2/3Y_1/3)₂AlC ceramics were prepared by Mo, Y, Al, and graphite powders as raw materials. The phase composition, microstructure, element distribution, and pore structure characteristics were comprehensively studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Archimedes method, and bubble point method. A detailed investigation was conducted on the influence of sintering temperature on the phase composition. Possible routes of phase transition and pore formation mechanisms during the sintering process were provided. The experimental results reveal that at 650–850 °C, transition metals react with aluminum, forming aluminum-containing intermetallics and a small amount of carbides. At 850–1250 °C, transition metals collaborate with graphite, producing transition metal carbides. Then, at 1250–1450 °C, these aluminum intermetallics interact with transition metal carbides and remaining unreacted Y, Al, and C, yielding the final product (Mo_2/3Y_1/3) ₂AlC. Simultaneously, the pore structure alters correspondingly with the solid-phase reaction at different reaction temperatures.