Tantalum-containing SiBEA zeolite with isolated framework mononuclear Ta(V) doped with Ag, Cu and Zn were prepared and characterized by XRD, XPS, DR UV-VIS and FTIR (with 2 of additional dehydrogenation sites. Such modification allows accelerating ethanol dehydrogenation to acetaldehyde and subsequent steps of the ethanol-to-butadiene process.Ethanol conversion and butadiene selectivity over the catalysts increase in the order: TaSiBEA < ZnTaSiBEA < AgTaSiBEA < CuTaSiBEA. Higher selectivity to butadiene (73 %) was achieved over CuTaSiBEA (at 88% ethanol conversion, T = 598 К, WHSV = 0.5 h -1 ). 22ASSOCIATED CONTENT Supporting Information. The details of the calculations of the amount of recycled CO 2 in 1,3-butadiene production from biomass, XP spectra, TEM images and diffraction patterns, additional catalytic results. This material is available free of charge via the Internet at http://pubs.acs.org. AUTHOR INFORMATION Corresponding Authors* E-mails: pavlo_kyriienko@ukr.net (P.K.) and stanislaw.dzwigaj@upmc.fr (S.D.).

We have examined the aging behavior of spin-cast thin polymer films as a function of their processing history. Films prepared from solutions close to the Θ temperature were aged for varying times at room temperature, followed by a dewetting experiment above the glass transition temperature of the polymer. The characteristic aging time varied strongly with the quality of the solvent, which is attributed to distorted chain conformations in the as-cast films. This is an indication for the nonequilibrium nature of thin polymer films, possibly causing some of their unexplained properties.

Classical antibacterial surfaces usually involve antiadhesive and/or biocidal strategies. Glycosylated surfaces are usually used to prevent biofilm formation via antiadhesive mechanisms. We report here the first example of a glycosylated surface with biocidal properties created by the covalent grafting of sophorolipids (a sophorose unit linked by a glycosidic bond to an oleic acid) through a self-assembled monolayer (SAM) of short aminothiols on gold (111) surfaces. The biocidal effect of such surfaces on Gram+ bacteria was assessed by a wide combination of techniques including microscopy observations, fluorescent staining and bacterial growth tests. About 50% of the bacteria are killed via alteration of the cell envelope. In addition, the role of the sophorose unit and aliphatic chain configuration are highlighted by the lack of activity of substrates modified respectively with sophorose-free oleic acid and sophorolipid-derivative having a saturated aliphatic chain. This system 2 demonstrates thus the direct implication of a carbohydrate in the destabilization and disruption of the bacterial cell envelope.3

Brownmillerite SrCoO(2.5) (010) thin films synthesized by pulsed laser deposition became amorphous when reduced at low temperatures by CaH(2), indicating that the infinite-layer structure with the square planar Co(2+)O(4) configuration is unstable. Ferromagnetic and conducting perovskite SrCoO(3) epitaxial thin films, on the other hand, were obtained topotactically at room temperature by oxidation with NaClO.

To fight against nosocomial infection initiated by colonization of medical devices, a strategy enabling the direct and fast functionalization of silicone surfaces is proposed. This strategy proceeds in a site-specific way using original hybrid silylated antibacterial peptides. This safe and up-scalable method guarantees a covalent and robust immobilization with the correct orientation of the bioactive moiety. Importantly it also avoids multi-step chemical modifications of the surface or multi-layer polymer coatings. As proof of concept, antibacterial silicone catheter has been prepared whose immediate and long term efficiency is superior by comparison to similar silver-embedded materials.

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Four DNA polybases (polyA, polyC, polyG, and polyT), modified or not with an external NH2 group, have been immobilized on an original, robust, and low-cost Ag°/TiO2 surface-enhanced Raman spectroscopy (SERS) platform. The latter was elaborated through an optimized chemically assisted photocatalytic reduction process. The label-free SERS detection of these polybases has been performed, and the analysis of SERS spectra has been supported by X-ray photoelectron spectroscopy measurements. The high-resolution and signal/noise ratio of SERS spectra enabled us to clearly index the main and secondary Raman lines of all types of studied polybases and to propose some aspects of the polybase immobilization mechanism. Regardless of polybase type and presence or absence of NH2 modification, an optimum detection is obtained for polybase concentrations lying in the 5–10 μM range, which gives rise to reproducible SERS spectra. This behavior has been interpreted in terms of distribution, orientation, and packing density of immobilized molecules.