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Murviel-lès-Montpellier, France

Escande V.,French National Center for Scientific Research | Olszewski T.K.,Wroclaw University of Technology | Petit E.,Institute Europeen des Membranes | Grison C.,French National Center for Scientific Research
ChemSusChem | Year: 2014

Polymetallic hyperaccumulating plants growing on wastes from former mining activity were used as the starting material in the preparation of novel plant-based Lewis acid catalysts. The preparation of biosourced Lewis acid catalysts is a new way to make use of mining wastes. These catalysts were characterized by X-ray fluorescence, X-ray diffraction, inductively coupled plasma mass spectrometry, and direct infusion electrospray ionization mass spectrometry. These analyses revealed a complex composition of metal species, present mainly as polymetallic chlorides. The catalysts proved to be efficient and recyclable in a solid-state version of the Garcia Gonzalez reaction, which has been underexploited until now in efforts to use carbohydrates from biomass. This methodology was extended to various carbohydrates to obtain the corresponding polyhydroxyalkyl furans in 38-98 % yield. These plant-based catalysts may be a better alternative to classical Lewis acid catalysts that were previously used for the Garcia Gonzalez reaction, such as ZnCl2, FeCl3, and CeCl3, which are often unrecyclable, require aqueous treatments, or rely on metals, the current known reserves of which will be consumed in the coming decades. Moreover, the plant-based catalysts allowed novel control of the Garcia Gonzalez reaction, as two different products were obtained depending on the reaction conditions. Common-or-garden variety catalyst: Polymetallic hyperaccumulating plants are used in the preparation of Lewis acid plant-based catalysts. The catalysts efficiently mediate the Garcia Gonzalez reaction to furnish platform molecules from carbohydrates. Efficiency, generality of application, ease of control of the reaction selectivity, use of solid-state reactions, and the capacity to recover and reuse polymetallic catalysts are the key advantages of the presented approach. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Rodriguez-Castillo M.,Charles Gerhardt Institute | Laurencin D.,Charles Gerhardt Institute | Tielens F.,CNRS Laboratory of Condensed Matter Chemistry, Paris | Van Der Lee A.,Institute Europeen des Membranes | And 3 more authors.
Dalton Transactions | Year: 2014

The reaction of gold nanoparticles with benzimididazol-2-ylidene ligands leads to the formation of well-defined bis-carbene gold(i) complexes, as shown by characterization techniques such as powder XRD and solid state NMR. This journal is © the Partner Organisations 2014. Source

Barboiu M.,Institute Europeen des Membranes | Barboiu M.,Petru Poni Institute of Macromolecular Chemistry
Chemical Communications | Year: 2016

Aquaporins (AQPs) are biological water channels known for fast water transport (∼108-109 water molecules per s per channel), with complete proton/ion exclusion. Few synthetic channels have been designed to mimic this high water permeability and to reject ions at a significant level. This Feature Article will discuss the incipient developments of the first artificial water channel systems. © The Royal Society of Chemistry 2016. Source

Merian T.,University of Maine, France | Debarnot D.,University of Maine, France | Rouessac V.,Institute Europeen des Membranes | Poncin-Epaillard F.,University of Maine, France
Talanta | Year: 2010

The ammonia absorption properties of polyaniline elaborated by the pulsed-plasma technique are studied. These properties depend on the structure of the polymer which is associated not only to plasma parameters such as peak power, ignition and extinction durations, pulse frequency and duty cycle, but also to the type of doping agent. Two methods of analysis are used: the UV/vis spectrometry and the quartz crystal microbalance. The results show that input power is the most influent plasma parameter on the sensitivity of the polyaniline film. Moreover, the oxidative doping is more efficient than the acidic one to create more polarons and then to obtain a more sensitive layer. The gravimetric study shows that the interaction between ammonia molecules and iodine-doped polyaniline corresponds to a multilayer reversible chemisorption. © 2010 Elsevier B.V. All rights reserved. Source

Habrioux A.,University of Poitiers | Napporn T.,University of Poitiers | Servat K.,University of Poitiers | Tingry S.,Institute Europeen des Membranes | Kokoh K.B.,University of Poitiers
Electrochimica Acta | Year: 2010

A new biocathode was built and tested. It consisted of bilirubin oxidase adsorbed on Vulcan XC 72 R and immobilized into a Nafion® matrix. The possibility of direct electron transfer between bilirubin oxidase and Vulcan XC 72 R was also demonstrated. The kinetics on biocathode were enhanced by including 2,2′-azinobis-3-ethylbenzothiazoline-5-sulfonic acid in the catalytic film. A first order reaction rate was observed for oxygen concentrations lower than 22%. A complete kinetic investigation of the system was shown. A biofuel cell test performed with this biocathode and Au 70Pt30 nanoparticles as anode catalyst permitted to reach a power density of 170 μW cm-2 at a cell voltage of 0.6 V, which is superior to what can be obtained with the concentric design. © 2009 Elsevier Ltd. Source

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