We present a thin metasurface with large microwave absorptivity and low infrared emissivity simultaneously. By properly tuning the resonance peaks and impedance of the meta-atom, broadband microwave absorptivity greater than 90% from 8.2 to 16.0 GHz is achieved. In the meantime, owing to large coverage of periodic metal patches on the top surface, low infrared emissivity is exhibited in the infrared region (IR) of 8 µm–14 µm. The excellent agreement between numerical simulation and experimental result demonstrates the good performance of the proposed metasurface. Due to the usage of polymethacrylimide (PMI) and polyethylene terephthalate (PET) as the substrate, the metasurface is especially advantageous for the light weight, making it a favorite in real engineering applications.

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In this article, an adaptive magnetorheological elastomer bearing prototype for seismic mitigation of bridge superstructures is designed and manufactured. The magnetorheological elastomer bearing is developed featuring conventional laminated structure in the seismic rubber bearing. Besides, the magnetic circuit design of the laminated magnetorheological elastomer bearing is verified by electromagnetic analysis, and a base-isolated testing system is established to obtain the acceleration transmissibility under various applied currents. The experimental results indicate that the resonance frequency of the integrated system can be tuned from 10 to 20 Hz, and the transmissibility peak value reduces 20.67% simultaneously, for which the proposed bearing can be used for seismic mitigation. Finally, the stiffness and damping of the laminated magnetorheological elastomer bearing integrated vibration mitigation system are identified by the response characteristics.

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