Digital twin (DT) technology is emerging as a core solution for future marine development and intelligent ocean management. The review systematically reviews digital twin applications in the marine field, clarifies its concept, proposes a five-layer framework, and summarizes key technologies, including sensing, data management, modeling, simulation, and monitoring. It highlights DT’s ability to synchronize physical marine systems with virtual models in real time, enabling simulation, prediction, optimization, and decision-making. The authors further outline challenges and development prospects, showing how DT can support deep-sea resource exploitation, offshore wind energy, marine engineering, vessel autonomy, environmental monitoring, and system reliability assessment.

Polyoxometalates are promising inorganic drugs with antiviral activity; however, they pose a risk to humans because of their potential accumulation in the body. Polyoxometalates encapsulated with berberine from a traditional Chinese herb may exhibit lower cytotoxicity. In this study, the antiviral effects of four berberine-based organic–polyoxometalate hybrids (BR-POMs) on BHK-21 and PK-15 cells were evaluated in vitro using encephalomyocarditis virus (EMCV) or pseudorabies virus (PRV) models. The collected cells were used for quantitative polymerase chain reaction analysis. The supernatants were collected to quantify the viral loads using a TCID50 assay in vitro. EC50 and CC50 were determined through dose–response experiments, and the EC50/CC50 ratio was used as a selectivity index to measure the antiviral activity. The results demonstrate that all BR-POMs exhibited certain antiviral activity. The BR-POMs did not exert toxicity against the EMCV- or PRV-infected cells at the tested concentration (CC50 > 40 μM). Notably, BR-EuSiW (EC50 15.07 μM, CC50 651.2 µM, SI 43.21) exerted antiviral effects by acting on the virus at its biosynthesis stage, thereby inhibiting virus proliferation in a dose-dependent manner. This study demonstrates that organic–polyoxometalate hybrids represent a new strategy for developing antivirals against EMCV.

Underwater wireless power transfer is emerging as a key technology for enabling long-duration, maintenance-free operation of autonomous underwater vehicles (AUVs). This review provides the most comprehensive overview to date of magnetic-coupling-based underwater wireless charging, addressing challenges such as eddy current losses in seawater, misalignment caused by ocean dynamics, and the growing need for simultaneous transfer of power and data. By comparing transmitter–receiver coil structures, compensation networks, and control strategies, the research identifies design pathways that significantly enhance efficiency, stability, and tolerance to dynamic marine conditions. The work also highlights emerging simultaneous wireless power and data transfer (SWPDT) methods that could reshape the future of marine sensing and robotic operations.

Heterogeneous interface engineering is key to tailoring intrinsic electromagnetic wave (EMW) attenuation. However, fully harnessing the functional benefits of these interfaces requires precise control of their architecture—a major challenge in hierarchical heterostructure design.