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In this paper, the Co3O4/MWCNTs/Graphene ternary composite was synthesized by a facile one‐pot hydrothermal method. The crystal structure, microstructure and elementary composition, electromagnetic parameters and microwave absorption property were systemically investigated by the XRD, SEM, TEM and VNA respectively. The results showed that the as‐prepared ternary composite exhibits enhanced absorption property in the frequency range of 0.1–3.0 GHz, which is mainly attributed to the synergistic effects of the dielectric loss and magnetic loss. The enhanced dielectric loss mainly generates from the strong dipole and interfacial polarization of the adherent MWCNTs and embedded graphene fragments, and the enhanced magnetic loss derives from eddy current loss and nature resonance together. The maximum reflection loss of this composite can reach −42.56 dB at 0.39 GHz with a thickness of 5 mm, while the maximum effective absorption bandwidth covers from 0.77 GHz to 1.99 GHz with a relatively thinner thickness of 2 mm. This study provides a facile method to synthesize Co3O4/MWCNTs/Graphene composite with excellent properties that is a potential candidate for microwave absorption in low frequency band.

Oceanic datasets derived from satellite altimeters are of great significance to physical oceanography and ocean dynamics research and the protection of marine environmental resources. Ageostrophic velocity induced by centrifugal force is not considered in altimeter products. This study introduces an iterative method to perform cyclogeostrophic corrections of mesoscale eddies’ surface velocities derived from satellite altimeters. The corrected eddy velocity field and geostrophic velocity field were compared by combining eddy detection and mathematical statistics methods. The results show that eddies with small curvature radii, high roundness, or Rossby number larger than 0.1 illustrate that cyclogeostrophic correction is required. The cyclogeostrophic velocity is greater (less) than the geostrophic velocity in anticyclonic (cyclonic) eddies. Additionally, the iterative method is applied to cyclogeostrophic-corrected multi-year (1998–2012) Kuroshio surface velocities. The effect of cyclogeostrophic correction is significant for the Kuroshio Extension region, where the maximum relative difference of velocities with and without correction is about 10% and the eddy kinetic energy is 20%.

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