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Colonization of ship hulls by living organisms, which occurs on molecular, microbial and macro organism levels, decreases ship performance, increases costs and is a biological problem with global consequences. Managing fouling is necessary for efficient economics and to prevent environmental damage due to introduction of invasive species. Colonization is managed by broad spectrum long-lived toxins which kill colonizers. Broad spectrum long-lived toxins build up and impact environments. Toxins damage ecosystems and directly or indirectly kill food species. Ideally, novel antifouling approaches will be compatible with existing business models and with the environment. A mixture of short-lived biologically active molecules that manage colonization has this potential. The mixture would contain a short-lived toxin that managed colonization of organisms that have no behavior and then additional molecules that interfere with the process of colonization by organisms with behavior and those that attach as part of a change in life stage. Environmentally benign antifouling approaches are novel and require cooperation rather than competition or adversarial relationships. They require cooperation by individuals with expertise from business, governmental agencies and academia. The science is likely to be easier than the necessary changes in philosophy and governance required to successfully address this and other complex global problems.

In the study, the Ag–SiO₂–APTES nanocomposite was synthesized via the self-assembly method to prepare Ag–SiO₂ and subsequently used 3-aminopropyltriethoxysilane (APTES) to functionalize its surface. The as-prepared Ag–SiO₂–APTES nanocomposite was embedded into poly(vinylidene fluoride) (PVDF) membrane by the co-blending way to fabricate the Ag–SiO₂–APTES membrane. The Ag–SiO₂–APTES nanocomposites were characterized by X-ray diffraction (XRD). These membrane materials were characterized by field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM) and FT-IR spectra. The performance of membrane was investigated simultaneously for removing the organic dye methylene blue (MB), Rhodamine B, Direct Red 28 and anti-microbial ability. The experimental results demonstrated that the Ag–SiO₂–APTES modified membrane were presented to be more hydrophilic with a contact angle 55.6${}^{\circ }$, whereas the pristine PVDF membrane was 81.8${}^{\circ }$. The dye rejection ratios were also improved after adding Ag–SiO₂–APTES, which reached 86.8% for MB, 87% Rhodamine B, 88% for Direct Red 28, besides, the removal rate of MB was about 98.7% at pH $=$ 11. More importantly, the Ag–SiO₂–APTES membranes exhibited excellent antifouling properties for treating MB solution and could reach 85% of flux recovery ratio after four cyclic experiment. Finally, via inhibition zone method of antimicrobial test Ag–SiO₂–APTES membrane exhibited the antimicrobial activity against Escherichia coli (E. coli) excellently. The novel antifouling and antibacterial Ag–SiO₂–APTES membrane has a potential for dye wastewater treatment and water purity.

Since TBT was banned from antifouling paints for boats, a search for new non-toxic antifouling compounds had conducted for decades. One of the most promising technologies to alternate toxic antifoulants is the development of naturally occurring compounds from organisms. In this study, the antifouling activity of ethanolic extracts from Konjak Amorphaphallus Konjacwas investigated. The extracts were tested against benthic diatom Navicula pinnain laboratory assays. The results indicated that the growth and reproduction of diatom was observably inhibited by the extracts. The extracts are composed of ceramide, and its apoptosis effect was the way that the extracts from Konjak limited the development of diatom. This finding suggests a potential approach for novel antifouling active ingredients.