An attempt is made to describe the fate and behavior of organic arsenic (As) compounds in the soil environment, based on an extensive literature researches. The objective of this review is to provide an overview on the state of knowledge to date about the occurrence and potential transformation of organic As, including methylation, degradation, and hydration, in soils and their uptake and accumulation in plants and animals. Accordingly, the biogeochemical cycle of organic As in the soil environment is proposed.

Single-layer proton exchange membranes (PEMs) have been under development for several decades. The current use of conductive polymers in PEM fuel cells has been limited primarily to single layered sulfonated fluoro polymers, e.g. Nafion. Although this architecture has certain positive characteristics, it lacks the robust properties required for use in high-temperature, low=humidity conditions. In this work, a multilayer composite PEM consisting of outer layers of sulfonated polyphenylsulfone (S-PPSU) and an inner layer blend of octa-sulfonated octaphenyl-POSS (S-POSS) and S-PPSU has been developed and shown to exhibit good conductivity, physical and chemical durability, and high strength. The multilayer composite PEM showed improved conductivity at 90 °C and 25% RH relative to analogous single-layer S-POSS-S-PPSU PEMs and to the typical sulfonated fluoro polymers currently in use.

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