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SiC/multi-walled carbon nanotube (MWCNT) composites are considered to be promising materials for high-temperature electromagnetic wave (EMW) absorption due to their strong thermal stability and tunable dielectric properties. However, the EMW absorption performance of these composites is limited by poor impedance matching. This study proposes a novel multiscale structure synergistic regulation approach to enhance EMW absorption performance, which involves constructing a heterointerface structure and a triple periodic minimal surface (TPMS) meta-structure. The addition of a SiO 2 shell as an impedance layer to the SiC/MWCNT core to improve the intrinsic impedance. Meanwhile, the heterointerface between the core-shell structure leads to multiple interface polarization, significantly enhancing EMW energy dissipation. Consequently, the effective absorption bandwidth (EAB) of SiO 2 –SiC/MWCNT composites increased from 0.88 to 4.56 GHz. Furthermore, a TPMS meta-structure, fabricated by three-dimensional (3D) printing and sol infiltration technology, is developed to further improve impedance matching with the equivalent electromagnetic effect. Simulation and experimental results demonstrate that the SiO 2 –SiC/MWCNT TPMS meta-structure exhibits broadband EMW absorption performance, with the EAB reaching 7.2 GHz. This improvement is attributed to the synergistic regulation of the heterointerface structure and TPMS meta-structure, which provides a good balance between the requirements of electromagnetic loss and impedance matching. Additionally, the composites exhibit excellent oxidation resistance, as their EAB remains almost unchanged after exposure to 1000 °C for 6 h. This research offers a new design paradigm for ultrabroadband design of the nonmagnetic high-temperature absorbing materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Bridge scouring is one of the factors affecting the safety of bridge. Considering the energy loss and sand-bed, a prediction model equation (PMEL) had been proposed to estimate the cylindrical bridge piers scour depth. The influence of energy loss on the accuracy of local scour depth prediction was discussed. The energy loss caused by the interaction between the flow field with the pier and the riverbed was introduced, and the reduction of effective peak velocity in a reciprocating flow was considered. This paper adopted eighteen data sets from cylindrical bridge piers scouring experiments that combined numerical simulation analysis. Then the relationship between the influence parameter H r (the non-dimensional effective fluid height) and V / V c (flow intensity) was established to guide the selection of calculated water depth. Finally, compared to directly using numerical simulation to solve the local scouring depth of bridge, the PMEL improved the solving efficiency. The accuracy of PMEL has been validated through physical experiments, standardized equations, and results from other researches. Compared with the local scour depth prediction model, without considering energy loss, it was found that the calculation accuracy had increased by 27%. • A local scour prediction model for Cylindrical bridge piers considering energy loss is established. • The relationship between effective water depth and flow intensity was proposed. • Compared to the standard equation and other prediction models, the new model has lower errors. [ABSTRACT FROM AUTHOR]