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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.

Membrane technologies are essential for water treatment, bioprocessing and chemical manufacturing. Stimuli-responsive membranes respond to changes in feed conditions (e.g., temperature, pH) or external stimuli (e.g., magnetic field, light) with a change in performance parameters (permeability, selectivity). This enables new functionalities such as tunable performance, self-cleaning and smart-valve behavior. Polymer self-assembly is a crucial tool for manufacturing such membranes using scalable methods, enabling easier commercialization. This review surveys approaches to impart stimuli responsive behavior to membrane filters using polymer self-assembly.

A scale-up nanoporous membrane centrifuge is designed and modeled. It can be used for nanoscale scale separation including reverse osmosis desalination. There are micron-size pores on the wall of the centrifuge and nanoscale pores on local graphene membrane patches that cover the micron-size pores. In this work, we derived the critical angular velocity required to counter-balance osmosis force, so that the reverse-osmosis (RO) desalination process can proceed. To validate this result, we conducted a large scale (four million atoms) full atom molecular dynamics (MD) simulation to examine the critical angular velocity required for reverse osmosis at nanoscale. It is shown that the analytical results derived based on fluid mechanics and the simulation results observed in MD simulation are consistent and well matched. The main advantage of such nanomaterial based centrifuge is its intrinsic anti-fouling ability to clear $N_a^{+}$ and ${Cl}^{-}$ ions accumulated at the vicinity of the pores due to the Coriolis effect. Analyses have been conducted to study the relation between osmotic pressure, centrifugal pressure, and water permeability.