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The purpose of this work is the development and characterisation of new hybrid polysaccharide (FucoPol) membranes. These membranes were prepared by incorporation of a SiO 2 network homogeneously dispersed by using a sol-gel method with GPTMS as a crosslinker silica precursor. They were further crosslinked with CaCl 2 for reinforcement of mechanical properties and improvement of their permeation performance. They were characterised in terms of their structural, mechanical and thermal properties. They presented a dense and homogeneous structure, resistant to deformation, with a Tg of 43 °C and a thermal decomposition between 240 and 251 °C. The hybrid FucoPol membranes were tested for ethanol dehydration by pervaporation and also for nitrogen dehydration. They exhibited high water selectivity values, similar to PERVAP ® 4101, however they lost their stability when exposed to solutions of 10.0 wt.% water in ethanol. In contrast, these membranes were stable when applied in N 2 dehydration, leading to reproducible performance and very high water selectivities., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

One of the main differences between bacteria and archaea concerns their membrane composition. Whereas bacterial membranes are made up of glycerol-3-phosphate ester lipids, archaeal membranes are composed of glycerol-1-phosphate ether lipids. Here, we report the construction of a stable hybrid heterochiral membrane through lipid engineering of the bacterium Escherichia coli By boosting isoprenoid biosynthesis and heterologous expression of archaeal ether lipid biosynthesis genes, we obtained a viable E. coli strain of which the membranes contain archaeal lipids with the expected stereochemistry. It has been found that the archaeal lipid biosynthesis enzymes are relatively promiscuous with respect to their glycerol phosphate backbone and that E. coli has the unexpected potential to generate glycerol-1-phosphate. The unprecedented level of 20-30% archaeal lipids in a bacterial cell has allowed for analyzing the effect on the mixed-membrane cell's phenotype. Interestingly, growth rates are unchanged, whereas the robustness of cells with a hybrid heterochiral membrane appeared slightly increased. The implications of these findings for evolutionary scenarios are discussed., Competing Interests: The authors declare no conflict of interest., (Copyright © 2018 the Author(s). Published by PNAS.)

Ink-free rewritable media has attracted great attention as a potential alternative to current paper prints, owing to its benefits to reducing paper production and consumption for environmental protection. It is desirable to develop rewritable media based on cheap, robust, and fast-response photochromic systems. Herein, we report the design and fabrication of flexible and photorewritable PVP/a-WO 3 hybrid membranes through electrospinning, on which images with high resolution can be photoprinted and heat-erased for over 40 cycles. The well conjugated organic-inorganic hybrid structure endows a fast "electron-proton double injection" from PVP to a-WO 3 in the coloration process and greatly improves the photochromic responses. The coloration times can be as short as tens of seconds and the erasure times can be as long as 10 days in ambient conditions. As-formed photochromic membranes are low-cost, environmental benign and easy for large-scale production, indicate their great potential as flexible rewritable media for practical usage.

Graphene oxide-Ag nanoparticle composites were prepared through impregnation reduction using different reactants. Transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy analyses were performed to characterize differences in the morphologies of three different Ag-GO composites. Scanning electron microscopy, transmission electron microscopy, and differential scanning calorimetry analyses were also applied to evaluate the morphology and thermal stability of the hybrid membranes. Swelling-sorption and pervaporation experiments of benzene and cyclohexane were conducted to evaluate the separation performance of hybrid membranes containing different Ag-GO composites. Results demonstrated that small Ag nanoparticles generated through impregnation reduction using Ag(NH3)2(+) and PEG were homogeneously distributed in the hybrid membranes because of moderate reduction rate. The polymide (PI) hybrid membrane exhibited high separation performance. Increase in Ag content in the Ag-GO samples led to the formation of Ag particles on the GO surface; these particles enhanced the separation performance of the hybrid membranes. When Ag-GO samples with 15 mass percent added, the hybrid membrane showed the highest separation performance and its maximum separation factor in the pervaporation experiments reached 35. It is more than three times higher than that of the GO/PI hybrid membrane. Moreover, large Ag particles were formed and aggregated during the preparation and polymerization of Ag-GO samples with high Ag contents; these particles reduced the separation performance of the hybrid membranes., (Copyright © 2016 Elsevier Inc. All rights reserved.)