There are a large number of fouling organisms in the ocean, which easily attach to the surface of ships, oil platforms and breeding facilities, corrode the surface of equipment, accelerate the aging of equipment, affect the stability and safety of marine facilities and cause serious economic losses. Antifouling coating is an effective method to prevent marine biological fouling. Traditional organic tin and copper oxide coatings are toxic and will contaminate seawater and destroy marine ecology and have been banned or restricted. Environmentally friendly antifouling coatings have become a research hotspot. Among them, the use of natural biological products with antifouling activity as antifouling agents is an important research direction. In addition, some fouling release coatings without antifoulants, biomimetic coatings, photocatalytic coatings and other novel antifouling coatings have also developed rapidly. On the basis of revealing the mechanism of marine biofouling, this paper reviews the latest research strategies to develop environmentally friendly marine antifouling coatings. The composition, antifouling characteristics, antifouling mechanism and effects of various coatings were analyzed emphatically. Finally, the development prospects and future development directions of marine antifouling coatings are forecasted.

The use of bionic drag-reducing microstructures in artificial blood vessels can effectively reduce their resistance to blood flow. The characteristics of the blood vessel are analysed and simplified, and the resistance reduction effects of three bionic microstructure models, namely V-shaped, rectangular and semi-circular, are compared and analysed by numerical simulations, and the resistance reduction effects of the three groove structures in the tubular model are verified. The results show that the V-shaped groove structure occupies a smaller volume compared to the rectangular and semi-circular structures of the same size, has a significant drag reduction effect, is highly achievable and stable, and is the best choice as a drag reduction microstructure for artificial blood vessels. In addition, the wall shear stresses of the V-groove structure were further analysed to verify the shear effect of this microstructure in artificial blood vessels and to reveal the shear mechanism of the V-groove microstructure.