Nos publications
2019 |
Akhouairi, Siham; Ouachtak, Hassan; Addi, Abdelaziz Ait; Jada, Amane; Douch, Jamaa Natural Sawdust as Adsorbent for the Eriochrome Black T Dye Removal from Aqueous Solution (Article de journal) Water Air and Soil Pollution, 230 (8), p. 181, 2019. @article{Akhouairi2019, title = {Natural Sawdust as Adsorbent for the Eriochrome Black T Dye Removal from Aqueous Solution}, author = { Siham Akhouairi and Hassan Ouachtak and Abdelaziz Ait Addi and Amane Jada and Jamaa Douch}, doi = {10.1007/s11270-019-4234-6}, year = {2019}, date = {2019-08-01}, journal = {Water Air and Soil Pollution}, volume = {230}, number = {8}, pages = {181}, abstract = {This paper deals with the adsorption of an anionic dye, Eriochrome Black T (EBT), from aqueous solutions onto sawdust, which is a natural, eco-friendly, widespread, and a low-cost bio sorbent. The aim of the work is to append values to the wood industry waste. Thus, sawdust was used as adsorbent in both batch reactor (BR) and fixed bed column (FBC), and various operating parameters influencing the adsorption process were investigated. The kinetic and the equilibrium adsorption results were found to agree with, respectively, the prediction of the pseudo-second-order equation and the Langmuir model. This latter allowed also the determination of the maximum EBT dye adsorbed amount, which was found to be about 40.96mg EBT per gram of sawdust at pH=4, corresponding to % dye removal of about 80%. In addition, the influence of various parameters on the dye adsorption, such as the adsorbent dose, the aqueous phase pH, and the initial dye concentration, was also examined. In batch experiments, The EBT adsorbed amount was found to increase either by increasing the amount of sawdust or by decreasing the aqueous phase pH, whereas, in the fixed bed column, the EBT retention was found to increase by decreasing the flow rate of the dye through the column. The overall data indicate that the EBT adsorption is mainly governed by the electrostatic interactions occurring between the adsorbent material and the dye.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper deals with the adsorption of an anionic dye, Eriochrome Black T (EBT), from aqueous solutions onto sawdust, which is a natural, eco-friendly, widespread, and a low-cost bio sorbent. The aim of the work is to append values to the wood industry waste. Thus, sawdust was used as adsorbent in both batch reactor (BR) and fixed bed column (FBC), and various operating parameters influencing the adsorption process were investigated. The kinetic and the equilibrium adsorption results were found to agree with, respectively, the prediction of the pseudo-second-order equation and the Langmuir model. This latter allowed also the determination of the maximum EBT dye adsorbed amount, which was found to be about 40.96mg EBT per gram of sawdust at pH=4, corresponding to % dye removal of about 80%. In addition, the influence of various parameters on the dye adsorption, such as the adsorbent dose, the aqueous phase pH, and the initial dye concentration, was also examined. In batch experiments, The EBT adsorbed amount was found to increase either by increasing the amount of sawdust or by decreasing the aqueous phase pH, whereas, in the fixed bed column, the EBT retention was found to increase by decreasing the flow rate of the dye through the column. The overall data indicate that the EBT adsorption is mainly governed by the electrostatic interactions occurring between the adsorbent material and the dye. |
Fakir, Abdellah Ait El; Anfar, Zakaria; Benafqir, Mohamed; Jada, Amane; Alem, Noureddine El Journal of Chemical Technology and Biotechnology, 94 (8), p. 2609–2620, 2019. @article{ElFakir2019, title = {Polyaniline coated hematite sand supported on graphene oxide (HS@PANI-GO) as a new magnetic material for advanced catalytic oxidation based on sulfate radicals: optimization using response surface methodology}, author = { Abdellah Ait El Fakir and Zakaria Anfar and Mohamed Benafqir and Amane Jada and Noureddine El Alem}, doi = {10.1002/jctb.6070}, year = {2019}, date = {2019-08-01}, journal = {Journal of Chemical Technology and Biotechnology}, volume = {94}, number = {8}, pages = {2609--2620}, abstract = {BACKGROUND We report here on the synthesis of a new magnetic and natural material: polyaniline coated hematite sand supported on graphene oxide (HS@PANI-GO) which was used as an heterogeneous catalyst to activate persulfate (PS) for aqueous solution Orange G (OG) degradation. RESULTS The characterization results have revealed that the hematite sand is rich in iron oxide, and the inorganic particles were well coated with polyaniline and successfully dispersed in graphene oxide. Further, catalytic oxidation experiments demonstrated that HS@PANI-GO material exhibited high activity in the PS activation for the OG degradation. It was found that complete OG removal from aqueous solution was achieved in 90 min at natural pH. In addition, the influence of various reaction conditions such as temperature, concentration of PS, catalyst dose, pH and decomposition time over the HS@PAN-GO/PS system were investigated and optimized. The catalyst HS@PAN-GO could be recycled easily by a magnet with good reusability. Finally, the effects of various parameters such as PS concentration, catalyst dose, initial OG concentration, and contact time, were investigated using the response surface methodology (RSM). It transpires that the experimental elimination of OG is 98.14%, as obtained under optimal conditions, was very close to the predicted value (96.58%) determined by RSM. CONCLUSION This study provides a promising way for the activation of green oxidant 'PS', by using a new magnetic composite suited for environmental remediation and oxidation catalysis. (c) 2019 Society of Chemical Industry}, keywords = {}, pubstate = {published}, tppubtype = {article} } BACKGROUND We report here on the synthesis of a new magnetic and natural material: polyaniline coated hematite sand supported on graphene oxide (HS@PANI-GO) which was used as an heterogeneous catalyst to activate persulfate (PS) for aqueous solution Orange G (OG) degradation. RESULTS The characterization results have revealed that the hematite sand is rich in iron oxide, and the inorganic particles were well coated with polyaniline and successfully dispersed in graphene oxide. Further, catalytic oxidation experiments demonstrated that HS@PANI-GO material exhibited high activity in the PS activation for the OG degradation. It was found that complete OG removal from aqueous solution was achieved in 90 min at natural pH. In addition, the influence of various reaction conditions such as temperature, concentration of PS, catalyst dose, pH and decomposition time over the HS@PAN-GO/PS system were investigated and optimized. The catalyst HS@PAN-GO could be recycled easily by a magnet with good reusability. Finally, the effects of various parameters such as PS concentration, catalyst dose, initial OG concentration, and contact time, were investigated using the response surface methodology (RSM). It transpires that the experimental elimination of OG is 98.14%, as obtained under optimal conditions, was very close to the predicted value (96.58%) determined by RSM. CONCLUSION This study provides a promising way for the activation of green oxidant 'PS', by using a new magnetic composite suited for environmental remediation and oxidation catalysis. (c) 2019 Society of Chemical Industry |
Kirschner, Julie; Szillat, Florian; Bouzrati-Zerelli, Mariem; Becht, Jean-Michel; Klee, Joachim E; Lalevee, Jacques Iodonium sulfonates as high-performance coinitiators and additives for CQ-based systems: Toward aromatic amine-free photoinitiating systems (Article de journal) Journal of Polymer Science Part A-polymer Chemistry, 57 (15), p. 1664–1669, 2019. @article{Kirschner2019b, title = {Iodonium sulfonates as high-performance coinitiators and additives for CQ-based systems: Toward aromatic amine-free photoinitiating systems}, author = { Julie Kirschner and Florian Szillat and Mariem Bouzrati-Zerelli and Jean-Michel Becht and Joachim E. Klee and Jacques Lalevee}, doi = {10.1002/pola.29431}, year = {2019}, date = {2019-08-01}, journal = {Journal of Polymer Science Part A-polymer Chemistry}, volume = {57}, number = {15}, pages = {1664--1669}, abstract = {Iodonium sulfonates are proposed here as a new class of high-performance coinitiators for camphorquinone (CQ)-based systems for the polymerization of methacrylates under blue light irradiation. When combined with CQ, the new proposed coinitiators present excellent polymerization performances and are excellent candidates for the replacement of tertiary aromatic amines subjected to toxicological concerns in the well-established CQ/amine photoinitiating system (PIS). Remarkably, good bleaching properties are obtained after polymerization. The use of the new PIS for dental adhesives is also investigated. (c) 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019}, keywords = {}, pubstate = {published}, tppubtype = {article} } Iodonium sulfonates are proposed here as a new class of high-performance coinitiators for camphorquinone (CQ)-based systems for the polymerization of methacrylates under blue light irradiation. When combined with CQ, the new proposed coinitiators present excellent polymerization performances and are excellent candidates for the replacement of tertiary aromatic amines subjected to toxicological concerns in the well-established CQ/amine photoinitiating system (PIS). Remarkably, good bleaching properties are obtained after polymerization. The use of the new PIS for dental adhesives is also investigated. (c) 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 |
Massara, Natalia; Marjaoui, Adil; Stephan, Regis; Hanf, Marie-Christine; Derivaz, Mickael; Dentel, Didier; Hajjar-Garreau, Samar; Mehdaoui, Ahmed; Diani, Mustapha; Sonnet, Philippe; Pirri, Carmelo Experimental molecular adsorption: electronic buffer effect of germanene on Al(111) (Article de journal) 2d Materials, 6 (3), p. 035016, 2019. @article{Massara2019, title = {Experimental molecular adsorption: electronic buffer effect of germanene on Al(111)}, author = { Natalia Massara and Adil Marjaoui and Regis Stephan and Marie-Christine Hanf and Mickael Derivaz and Didier Dentel and Samar Hajjar-Garreau and Ahmed Mehdaoui and Mustapha Diani and Philippe Sonnet and Carmelo Pirri}, doi = {10.1088/2053-1583/ab1601}, year = {2019}, date = {2019-07-01}, journal = {2d Materials}, volume = {6}, number = {3}, pages = {035016}, abstract = {The interaction of organic C-60 molecules with germanene grown on Al(1 1 1) is investigated by experimental tools and calculations. By mean of scanning tunneling microscopy, we show that a single but disordered C-60 layer is formed upon deposition in the monolayer range. Density functional theory calculations indicate that van der Waals and electrostatic interactions are present between the C-60 layer and the germanene, without formation of covalent bond. Moreover, the C-60 molecules are adsorbed without major crystallographic and charge modifications at the interface between germanene and the Al(1 1 1) substrate. The predicted charge transfer from the Al(1 1 1) substrate to the C-60 molecules is very small, which means that the germanene layer acts as an electronic buffer between the highly electron attractor C-60 molecules and the large electron reservoir Al(1 1 1). This leaves the C-60 layer quite uncharged, and so preserves its electron attractor properties for further layers grown on it, in the design of new molecular sensors.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The interaction of organic C-60 molecules with germanene grown on Al(1 1 1) is investigated by experimental tools and calculations. By mean of scanning tunneling microscopy, we show that a single but disordered C-60 layer is formed upon deposition in the monolayer range. Density functional theory calculations indicate that van der Waals and electrostatic interactions are present between the C-60 layer and the germanene, without formation of covalent bond. Moreover, the C-60 molecules are adsorbed without major crystallographic and charge modifications at the interface between germanene and the Al(1 1 1) substrate. The predicted charge transfer from the Al(1 1 1) substrate to the C-60 molecules is very small, which means that the germanene layer acts as an electronic buffer between the highly electron attractor C-60 molecules and the large electron reservoir Al(1 1 1). This leaves the C-60 layer quite uncharged, and so preserves its electron attractor properties for further layers grown on it, in the design of new molecular sensors. |
Khiari, Besma; Jeguirim, Mejdi; Limousy, Lionel; Bennici, Simona Biomass derived chars for energy applications (Article de journal) Renewable & Sustainable Energy Reviews, 108 , p. 253–273, 2019. @article{Khiari2019b, title = {Biomass derived chars for energy applications}, author = { Besma Khiari and Mejdi Jeguirim and Lionel Limousy and Simona Bennici}, doi = {10.1016/j.rser.2019.03.057}, year = {2019}, date = {2019-07-01}, journal = {Renewable & Sustainable Energy Reviews}, volume = {108}, pages = {253--273}, abstract = {Biomass-derived chars present energy density values close to those of fossil fuels and therefore they are good candidates in electricity or heat production plants with only minor drawbacks compared to fossil fuels. Even if co-firing seems the most attractive solution for near-term applications, processes based on combustion and gasification (which are competing in dependence of the need of heat or electricity) are receiving renewed attention. Thanks to their high carbon content, and their high specific surface area and developed porous structure, biomass-derived chars can be treated and converted into activated carbons and applied in many different field (as energy storage materials for gaseous fuels, mainly hydrogen and methane, or as electrodes). They can constitute the raw materials for preparing synthetic graphite, which can be used in some types of batteries and fuel cells, and in carbon electrodes for electrochemical capacitors. The performances in terms of capacitance, electrical conductivity, potential, charge and discharge rates, power density, etc. have been reported to be very close to those of commercial devices. The recent progress in the activation protocols brought to higher fuel gas storage capacities, especially in cryogenic conditions and under high pressure, and opened the possibility to apply these materials in new application fields. In catalysis, advances in the use of biomass-derived chars and active carbons have been made thanks to the improvement of the modification techniques. The optimization of the engineering methodologies allows to lower the cost of the activation processes of biomass-derived chars and to tune the char properties to adapt them to the final application. The present paper aims to give a comprehensive survey of already-well-established or future potential energy applications of biomass-derived chars. A critical comparison of their use in different processes is reported and their modification by various catalytic, physical and chemical routes is detailed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Biomass-derived chars present energy density values close to those of fossil fuels and therefore they are good candidates in electricity or heat production plants with only minor drawbacks compared to fossil fuels. Even if co-firing seems the most attractive solution for near-term applications, processes based on combustion and gasification (which are competing in dependence of the need of heat or electricity) are receiving renewed attention. Thanks to their high carbon content, and their high specific surface area and developed porous structure, biomass-derived chars can be treated and converted into activated carbons and applied in many different field (as energy storage materials for gaseous fuels, mainly hydrogen and methane, or as electrodes). They can constitute the raw materials for preparing synthetic graphite, which can be used in some types of batteries and fuel cells, and in carbon electrodes for electrochemical capacitors. The performances in terms of capacitance, electrical conductivity, potential, charge and discharge rates, power density, etc. have been reported to be very close to those of commercial devices. The recent progress in the activation protocols brought to higher fuel gas storage capacities, especially in cryogenic conditions and under high pressure, and opened the possibility to apply these materials in new application fields. In catalysis, advances in the use of biomass-derived chars and active carbons have been made thanks to the improvement of the modification techniques. The optimization of the engineering methodologies allows to lower the cost of the activation processes of biomass-derived chars and to tune the char properties to adapt them to the final application. The present paper aims to give a comprehensive survey of already-well-established or future potential energy applications of biomass-derived chars. A critical comparison of their use in different processes is reported and their modification by various catalytic, physical and chemical routes is detailed. |
Cremoux, T; Batonneau-Gener, I; Moissette, A; Paillaud, J - L; Hureau, M; Ligner, E; Morais, C; Laforge, S; Marichal, C; Nouali, H Influence of framework Si/Al ratio and topology on electron transfers in zeolites (Article de journal) Physical Chemistry Chemical Physics, 21 (27), p. 14892–14903, 2019. @article{Cremoux2019, title = {Influence of framework Si/Al ratio and topology on electron transfers in zeolites}, author = { T. Cremoux and I. Batonneau-Gener and A. Moissette and J. -. L. Paillaud and M. Hureau and E. Ligner and C. Morais and S. Laforge and C. Marichal and H. Nouali}, doi = {10.1039/c9cp01166h}, year = {2019}, date = {2019-07-01}, journal = {Physical Chemistry Chemical Physics}, volume = {21}, number = {27}, pages = {14892--14903}, abstract = {H-ZSM-5 and H-*BEA zeolites were hydrothermally synthesized with different Si/Al ratios (similar to 12 to similar to 40). The physico-chemical properties of the resulting materials were fully characterized by several techniques (NMR, BET, PXRD, and pyridine thermal desorption followed by infrared spectroscopy). To assess the effect of the zeolite type and Si/Al ratio on sample reactivity, the charge separation processes between the zeolite framework and the adsorbed trans-stilbene (t-St) molecule were investigated by UV-visible diffuse reflectance and FT-Raman spectroscopy. The UV-visible absorption spectra obtained after t-St adsorption show a clear difference depending on the zeolite type. It appears that the radical cation resulting from t-St spontaneous ionization is more stabilized in the MFI-type framework than in the *BEA topology. However, the amount and stability of the electron-hole pair resulting from the radical cation evolution to a charge transfer complex are more important in the *BEA zeolite. On the basis of the experimental results and physico-chemical properties of the sample, we found that the radical cation and the electron-hole stabilities are strongly dependent on the amount of hexacoordinated aluminum (Al-(VI)) and more precisely on their environment, i.e. the distance between Bronsted sites and strong Lewis sites or Bronsted Strong Lewis Pairs (BSLPs).}, keywords = {}, pubstate = {published}, tppubtype = {article} } H-ZSM-5 and H-*BEA zeolites were hydrothermally synthesized with different Si/Al ratios (similar to 12 to similar to 40). The physico-chemical properties of the resulting materials were fully characterized by several techniques (NMR, BET, PXRD, and pyridine thermal desorption followed by infrared spectroscopy). To assess the effect of the zeolite type and Si/Al ratio on sample reactivity, the charge separation processes between the zeolite framework and the adsorbed trans-stilbene (t-St) molecule were investigated by UV-visible diffuse reflectance and FT-Raman spectroscopy. The UV-visible absorption spectra obtained after t-St adsorption show a clear difference depending on the zeolite type. It appears that the radical cation resulting from t-St spontaneous ionization is more stabilized in the MFI-type framework than in the *BEA topology. However, the amount and stability of the electron-hole pair resulting from the radical cation evolution to a charge transfer complex are more important in the *BEA zeolite. On the basis of the experimental results and physico-chemical properties of the sample, we found that the radical cation and the electron-hole stabilities are strongly dependent on the amount of hexacoordinated aluminum (Al-(VI)) and more precisely on their environment, i.e. the distance between Bronsted sites and strong Lewis sites or Bronsted Strong Lewis Pairs (BSLPs). |
Ghali, Mariem; Brahmi, Chaima; Benltifa, Mahmoud; Dumur, Frederic; Duval, Sylvain; Simonnet-Jegat, Corine; Morlet-Savary, Fabrice; Jellali, Salah; Bousselmi, Latifa; Lalevee, Jacques New hybrid polyoxometalate/polymer composites for photodegradation of eosin dye (Article de journal) Journal of Polymer Science Part A-polymer Chemistry, 57 (14), p. 1538–1549, 2019. @article{Ghali2019, title = {New hybrid polyoxometalate/polymer composites for photodegradation of eosin dye}, author = { Mariem Ghali and Chaima Brahmi and Mahmoud Benltifa and Frederic Dumur and Sylvain Duval and Corine Simonnet-Jegat and Fabrice Morlet-Savary and Salah Jellali and Latifa Bousselmi and Jacques Lalevee}, doi = {10.1002/pola.29416}, year = {2019}, date = {2019-07-01}, journal = {Journal of Polymer Science Part A-polymer Chemistry}, volume = {57}, number = {14}, pages = {1538--1549}, abstract = {New polyoxometalate (POM)/polymer hybrid composites were prepared by photopolymerization under mild conditions for suitable photocatalytic processes. Polyoxometalates were incorporated in special photosensitive resins, which were photopolymerized under visible light to obtain new materials with photocatalytic activity for dye removal. The synthesized composites were characterized by real-time FT-IR, and the photocatalytic ability was investigated on Eosin-Y removal using photolysis under near UV irradiation. Interestingly, the polyoxometalates keep their photocatalytic properties, while incorporated into the polymeric matrix since very high conversion rates of Eosin-Y were achieved. Indeed, degradation efficiencies of about 98% and 93% were registered when using H3PMo12O40/polymer and 94% for SiMo12O40(IPh2)(4)/polymer composites, respectively. These first results reported in this article show that the new synthesized POM/polymer composites could be considered as promising materials for green and more suitable organic dye removal from aqueous solutions. (c) 2019 Wiley Periodicals, Inc.}, keywords = {}, pubstate = {published}, tppubtype = {article} } New polyoxometalate (POM)/polymer hybrid composites were prepared by photopolymerization under mild conditions for suitable photocatalytic processes. Polyoxometalates were incorporated in special photosensitive resins, which were photopolymerized under visible light to obtain new materials with photocatalytic activity for dye removal. The synthesized composites were characterized by real-time FT-IR, and the photocatalytic ability was investigated on Eosin-Y removal using photolysis under near UV irradiation. Interestingly, the polyoxometalates keep their photocatalytic properties, while incorporated into the polymeric matrix since very high conversion rates of Eosin-Y were achieved. Indeed, degradation efficiencies of about 98% and 93% were registered when using H3PMo12O40/polymer and 94% for SiMo12O40(IPh2)(4)/polymer composites, respectively. These first results reported in this article show that the new synthesized POM/polymer composites could be considered as promising materials for green and more suitable organic dye removal from aqueous solutions. (c) 2019 Wiley Periodicals, Inc. |
Qin, Zhengxing; Pinard, Ludovic; Benghalem, Mohammed Amine; Daou, Jean T; Melinte, Georgian; Ersen, Ovidiu; Asahina, Shunsuke; Gilson, Jean-Pierre; Valtchev, Valentin Preparation of Single-Crystal "House-of-Cards"-like ZSM-5 and Their Performance in Ethanol-to-Hydrocarbon Conversion (Article de journal) Chemistry of Materials, 31 (13), p. 4639–4648, 2019. @article{Qin2019, title = {Preparation of Single-Crystal "House-of-Cards"-like ZSM-5 and Their Performance in Ethanol-to-Hydrocarbon Conversion}, author = { Zhengxing Qin and Ludovic Pinard and Mohammed Amine Benghalem and T. Jean Daou and Georgian Melinte and Ovidiu Ersen and Shunsuke Asahina and Jean-Pierre Gilson and Valentin Valtchev}, doi = {10.1021/acs.chemmater.8b04970}, year = {2019}, date = {2019-07-01}, journal = {Chemistry of Materials}, volume = {31}, number = {13}, pages = {4639--4648}, abstract = {The present study reports the unbiased chemical etching of micron-sized ZSM-5 crystals with an NH4F solution, resulting in house-of-cards-like single crystals containing large rectangular cavities surrounded by thin (15-30 nm), flat, and highly crystalline walls. The formation of such house-of-cards-like architecture is a result of the preferential extraction of misoriented nanocrystalline domains followed by the uniform dissolution of the remaining part of the crystal. The characteristic features of NH4F-treated zeolites are the retention of framework composition (Si/Al) and Bronsted acidity, high crystallinity, a moderate increase in the external surface area, and increased accessibility to their active sites. Such a combination produces zeolite catalysts with superior performances (activity, stability, and coke resistance) in the ethanol-to-hydrocarbon conversion. The physicochemical properties of this newly engineered zeolite are compared to those of a hierarchical zeolite obtained by caustic leaching and zeolite nanosheets synthesized with a bifunctional template, a diquaternary ammonium-type surfactant.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The present study reports the unbiased chemical etching of micron-sized ZSM-5 crystals with an NH4F solution, resulting in house-of-cards-like single crystals containing large rectangular cavities surrounded by thin (15-30 nm), flat, and highly crystalline walls. The formation of such house-of-cards-like architecture is a result of the preferential extraction of misoriented nanocrystalline domains followed by the uniform dissolution of the remaining part of the crystal. The characteristic features of NH4F-treated zeolites are the retention of framework composition (Si/Al) and Bronsted acidity, high crystallinity, a moderate increase in the external surface area, and increased accessibility to their active sites. Such a combination produces zeolite catalysts with superior performances (activity, stability, and coke resistance) in the ethanol-to-hydrocarbon conversion. The physicochemical properties of this newly engineered zeolite are compared to those of a hierarchical zeolite obtained by caustic leaching and zeolite nanosheets synthesized with a bifunctional template, a diquaternary ammonium-type surfactant. |
Prevost, Victor; Anselme, Karine; Gallet, Olivier; Hindie, Mathilde; Petithory, Tatiana; Valentin, Jules; Veuillet, Mathieu; Ploux, Lydie Real-Time Imaging of Bacteria/Osteoblast Dynamic Coculture on Bone Implant Material in an in Vitro Postoperative Contamination Model (Article de journal) Acs Biomaterials Science & Engineering, 5 (7), p. 3260–3269, 2019. @article{Prevost2019, title = {Real-Time Imaging of Bacteria/Osteoblast Dynamic Coculture on Bone Implant Material in an in Vitro Postoperative Contamination Model}, author = { Victor Prevost and Karine Anselme and Olivier Gallet and Mathilde Hindie and Tatiana Petithory and Jules Valentin and Mathieu Veuillet and Lydie Ploux}, doi = {10.1021/acsbiomaterials.9b00050}, year = {2019}, date = {2019-07-01}, journal = {Acs Biomaterials Science & Engineering}, volume = {5}, number = {7}, pages = {3260--3269}, abstract = {Biomedical implants are an important part of evolving modern medicine but have a potential drawback in the form of postoperative pathogenic infection. Accordingly, the "race for surface" combat between invasive bacteria and host cells determines the fate of implants. Hence, proper in vitro systems are required to assess effective strategies to avoid infection. In this study, we developed a real time observation model, mimicking postoperative contamination, designed to follow E. coli proliferation on a titanium surface occupied by human osteoblastic progenitor cells (STRO). This model allowed us to monitor E. coli invasion of human cells on titanium surfaces coated and uncoated with fibronectin. We showed that the surface colonization of bacteria is significantly enhanced on fibronectin coated surfaces irrespective of whether areas were uncovered or covered with human cells. We further revealed that bacterial colonization of the titanium surfaces is enhanced in coculture with STRO cells. Finally, this coculture system provides a comprehensive system to describe in vitro and in situ bacterial and human cells and their localization but also to target biological mechanisms involved in adhesion as well as in interactions with surfaces, thanks to fluorescent labeling. This system is thus an efficient method for studies related to the design and function of new biomaterials.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Biomedical implants are an important part of evolving modern medicine but have a potential drawback in the form of postoperative pathogenic infection. Accordingly, the "race for surface" combat between invasive bacteria and host cells determines the fate of implants. Hence, proper in vitro systems are required to assess effective strategies to avoid infection. In this study, we developed a real time observation model, mimicking postoperative contamination, designed to follow E. coli proliferation on a titanium surface occupied by human osteoblastic progenitor cells (STRO). This model allowed us to monitor E. coli invasion of human cells on titanium surfaces coated and uncoated with fibronectin. We showed that the surface colonization of bacteria is significantly enhanced on fibronectin coated surfaces irrespective of whether areas were uncovered or covered with human cells. We further revealed that bacterial colonization of the titanium surfaces is enhanced in coculture with STRO cells. Finally, this coculture system provides a comprehensive system to describe in vitro and in situ bacterial and human cells and their localization but also to target biological mechanisms involved in adhesion as well as in interactions with surfaces, thanks to fluorescent labeling. This system is thus an efficient method for studies related to the design and function of new biomaterials. |
Garra, Patxi; Dietlin, Celine; Morlet-Savary, Fabrice; Dumur, Frederic; Gigmes, Didier; Fouassier, Jean-Pierre; Lalevee, Jacques Redox two-component initiated free radical and cationic polymerizations: Concepts, reactions and applications (Article de journal) Progress in Polymer Science, 94 , p. 33–56, 2019. @article{Garra2019a, title = {Redox two-component initiated free radical and cationic polymerizations: Concepts, reactions and applications}, author = { Patxi Garra and Celine Dietlin and Fabrice Morlet-Savary and Frederic Dumur and Didier Gigmes and Jean-Pierre Fouassier and Jacques Lalevee}, doi = {10.1016/j.progpolymsci.2019.04.003}, year = {2019}, date = {2019-07-01}, journal = {Progress in Polymer Science}, volume = {94}, pages = {33--56}, abstract = {Redox polymerizations are of huge importance throughout academic and industrial polymer science. Many authors propose the reaction of reducing (Red) and oxidizing (Ox) agents to accelerate/initiate radical or cationic polymerizations. As a result of activation energies typically below 80 kJ/mol, such reactions can occur under mild conditions, e.g., at room temperature, with reduced energy consumptions and robust in applications, such as the fabrication of composites. However, a clear definition of redox polymerization can only be found in reviews dealing with redox free radical polymerizations (FRP) published twenty years ago (or more). Therefore, a fresh and broader update is provided here for more recent work. The concepts involved when the Redand Oxagents (constituting the redox initiating system) are mixed under mild conditions are presented, followed by a discussion of the redox FRP initiating systems in bulk. Initiating systems dealing with the redox cationic polymerization (CP) are reviewed, and parallels between conventional FRP/CP and controlled polymerizations, in which redox systems are used, is provided. Many redox agents are useful in both modes. Finally, dual-cure (redox/photochemical; redox dual FRP/CP) systems is presented and selected applications are reviewed. Altogether, the state of the art for redox two-component polymerizations is provided, along with some perspectives. (C) 2019 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Redox polymerizations are of huge importance throughout academic and industrial polymer science. Many authors propose the reaction of reducing (Red) and oxidizing (Ox) agents to accelerate/initiate radical or cationic polymerizations. As a result of activation energies typically below 80 kJ/mol, such reactions can occur under mild conditions, e.g., at room temperature, with reduced energy consumptions and robust in applications, such as the fabrication of composites. However, a clear definition of redox polymerization can only be found in reviews dealing with redox free radical polymerizations (FRP) published twenty years ago (or more). Therefore, a fresh and broader update is provided here for more recent work. The concepts involved when the Redand Oxagents (constituting the redox initiating system) are mixed under mild conditions are presented, followed by a discussion of the redox FRP initiating systems in bulk. Initiating systems dealing with the redox cationic polymerization (CP) are reviewed, and parallels between conventional FRP/CP and controlled polymerizations, in which redox systems are used, is provided. Many redox agents are useful in both modes. Finally, dual-cure (redox/photochemical; redox dual FRP/CP) systems is presented and selected applications are reviewed. Altogether, the state of the art for redox two-component polymerizations is provided, along with some perspectives. (C) 2019 Elsevier B.V. All rights reserved. |
Conder, J; Vaulot, C; Marino, C; Villevieille, C; Ghimbeu, C M Chitin and Chitosan-Structurally Related Precursors of Dissimilar Hard Carbons for Na-Ion Battery (Article de journal) Acs Applied Energy Materials, 2 (7), p. 4841–4852, 2019. @article{Conder2019, title = {Chitin and Chitosan-Structurally Related Precursors of Dissimilar Hard Carbons for Na-Ion Battery}, author = { J. Conder and C. Vaulot and C. Marino and C. Villevieille and C. M. Ghimbeu}, doi = {10.1021/acsaem.9b00545}, year = {2019}, date = {2019-07-01}, journal = {Acs Applied Energy Materials}, volume = {2}, number = {7}, pages = {4841--4852}, abstract = {Hard carbons (HCs) prepared from renewable precursors are promising cost-effective electrode-material candidates for the application in Na-ion battery. Usually these materials are derived from cellulose. Here, however, we demonstrate that other polysaccharides, such as chitin and chitosan, can be as well up-and-coming parent materials of HCs. Despite structural similarities, thermal decomposition of these two biopolymers proceeds differently, contributing to the discrepancies in physicochemical properties of resulting HCs. Although chitin- and chitosan-derived HCs have comparable d-spacings and crystallite sizes, solid-state pyrolysis of the former biopolymer leads to micromesoporous material with significant specific surface area, while that of chitosan yields nonporous carbon. Despite that, both materials deliver similar initial specific charge of 280 mAh g(-1) (at C/10 rate), and their electrochemical performance starts to diverge only upon longer cycling at higher rate. With time, inorganic contaminants present in chitosan-derived HC presumably delay the diffusion of Na ions to and within the electrode and slow the rate of electrochemical reactions, eventually triggering polarization buildup. Further optimization of the chitosan-derived HC through acid treatment enables unblocking some of the micropores and increasing the carbon content in this material, therefore enhancing its active surface area and suppressing continuous fading of the specific charge.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Hard carbons (HCs) prepared from renewable precursors are promising cost-effective electrode-material candidates for the application in Na-ion battery. Usually these materials are derived from cellulose. Here, however, we demonstrate that other polysaccharides, such as chitin and chitosan, can be as well up-and-coming parent materials of HCs. Despite structural similarities, thermal decomposition of these two biopolymers proceeds differently, contributing to the discrepancies in physicochemical properties of resulting HCs. Although chitin- and chitosan-derived HCs have comparable d-spacings and crystallite sizes, solid-state pyrolysis of the former biopolymer leads to micromesoporous material with significant specific surface area, while that of chitosan yields nonporous carbon. Despite that, both materials deliver similar initial specific charge of 280 mAh g(-1) (at C/10 rate), and their electrochemical performance starts to diverge only upon longer cycling at higher rate. With time, inorganic contaminants present in chitosan-derived HC presumably delay the diffusion of Na ions to and within the electrode and slow the rate of electrochemical reactions, eventually triggering polarization buildup. Further optimization of the chitosan-derived HC through acid treatment enables unblocking some of the micropores and increasing the carbon content in this material, therefore enhancing its active surface area and suppressing continuous fading of the specific charge. |
Zhou, Ruchun; Malval, Jean-Pierre; Jin, Ming; Spangenberg, Arnaud; Pan, Haiyan; Wan, Decheng; Morlet-Savary, Fabrice; Knopf, Stephan A two-photon active chevron-shaped type I photoinitiator designed for 3D stereolithography (Article de journal) Chemical Communications, 55 (44), p. 6233–6236, 2019. @article{Zhou2019, title = {A two-photon active chevron-shaped type I photoinitiator designed for 3D stereolithography}, author = { Ruchun Zhou and Jean-Pierre Malval and Ming Jin and Arnaud Spangenberg and Haiyan Pan and Decheng Wan and Fabrice Morlet-Savary and Stephan Knopf}, doi = {10.1039/c9cc02923k}, year = {2019}, date = {2019-06-01}, journal = {Chemical Communications}, volume = {55}, number = {44}, pages = {6233--6236}, abstract = {We present herein the properties of a highly reactive type I photoinitiator with significant 2PA cross-sections (delta(720nm) similar to 90 GM). We demonstrate that this new type of photocleavable system exhibits very efficient two-photon polymerization abilities with performances amplified by more than two orders of magnitude with regards to those of a commercially available type I photoinitiator (Lucirin TPO-L) which is extensively employed for multiphoton 3D stereolithography.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present herein the properties of a highly reactive type I photoinitiator with significant 2PA cross-sections (delta(720nm) similar to 90 GM). We demonstrate that this new type of photocleavable system exhibits very efficient two-photon polymerization abilities with performances amplified by more than two orders of magnitude with regards to those of a commercially available type I photoinitiator (Lucirin TPO-L) which is extensively employed for multiphoton 3D stereolithography. |
Ferjani, Ibn A; Jeguirim, M; Jellali, S; Limousy, L; Courson, C; Akrout, H; Thevenin, N; Ruidavets, L; Muller, A; Bennici, S The use of exhausted grape marc to produce biofuels and biofertilizers: Effect of pyrolysis temperatures on biochars properties (Article de journal) Renewable & Sustainable Energy Reviews, 107 , p. 425–433, 2019. @article{IbnFerjani2019, title = {The use of exhausted grape marc to produce biofuels and biofertilizers: Effect of pyrolysis temperatures on biochars properties}, author = { A. Ibn Ferjani and M. Jeguirim and S. Jellali and L. Limousy and C. Courson and H. Akrout and N. Thevenin and L. Ruidavets and A. Muller and S. Bennici}, doi = {10.1016/j.rser.2019.03.034}, year = {2019}, date = {2019-06-01}, journal = {Renewable & Sustainable Energy Reviews}, volume = {107}, pages = {425--433}, abstract = {The wine industry represents an important economic sector in the Mediterranean countries. Currently, grape marc is valorized for ethanol production by distillation process generating a second residue called exhausted grape marc (EGM) that should be properly managed in order to avoid any related negative impacts onto the environment. In the present investigation, an innovative strategy was proposed to convert EGM into biofuels and biofertilizers through thermochemical conversion process such as carbonization/pyrolysis technique. In order to select the appropriate operating parameters, the impact of the slow pyrolysis temperatures of EGM (from 300 to 700 degrees C) on biochar production yields as well as their physico-chemical characteristics were assessed. The experimental results showed that the biochars yields production decrease with increasing the pyrolysis temperature and reach a plateau above 500 degrees C. The biochar yield at 500 degrees C is around 33%, which is amongst the highest values obtained for food processing residues. The biochar physico-chemical characterization showed a higher surface area (253.4 m(2)/g) was obtained for the char prepared at 600 degrees C. However, the maximum nutrients contents, namely potassium, nitrogen and phosphorus were registered at 500 degrees C. Based on the biochar yields and characteristics, it seems that EGM biochar produced through slow pyrolysis at 500 degrees C could be considered as a promising biofertilizer for agricultural purposes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The wine industry represents an important economic sector in the Mediterranean countries. Currently, grape marc is valorized for ethanol production by distillation process generating a second residue called exhausted grape marc (EGM) that should be properly managed in order to avoid any related negative impacts onto the environment. In the present investigation, an innovative strategy was proposed to convert EGM into biofuels and biofertilizers through thermochemical conversion process such as carbonization/pyrolysis technique. In order to select the appropriate operating parameters, the impact of the slow pyrolysis temperatures of EGM (from 300 to 700 degrees C) on biochar production yields as well as their physico-chemical characteristics were assessed. The experimental results showed that the biochars yields production decrease with increasing the pyrolysis temperature and reach a plateau above 500 degrees C. The biochar yield at 500 degrees C is around 33%, which is amongst the highest values obtained for food processing residues. The biochar physico-chemical characterization showed a higher surface area (253.4 m(2)/g) was obtained for the char prepared at 600 degrees C. However, the maximum nutrients contents, namely potassium, nitrogen and phosphorus were registered at 500 degrees C. Based on the biochar yields and characteristics, it seems that EGM biochar produced through slow pyrolysis at 500 degrees C could be considered as a promising biofertilizer for agricultural purposes. |
Zuo, X L; Song, H S; Shao, H J; Wei, T; Guo, J B Aging of OMMT/halogen-antimony-filled LGFPA6 composite: Effect on static and dynamic mechanical properties and fire behaviors (Article de journal) Polymer Composites, 40 (6), p. 2208–2218, 2019. @article{Zuo2019, title = {Aging of OMMT/halogen-antimony-filled LGFPA6 composite: Effect on static and dynamic mechanical properties and fire behaviors}, author = { X. L. Zuo and H. S. Song and H. J. Shao and T. Wei and J. B. Guo}, doi = {10.1002/pc.25026}, year = {2019}, date = {2019-06-01}, journal = {Polymer Composites}, volume = {40}, number = {6}, pages = {2208--2218}, abstract = {The static and dynamic mechanical properties and fire behaviors for long-glass-fiber reinforced polyamide 6 composite filled with organo-modified montmorillonite/brominated epoxy resins/antimony trioxide (OMMT/FR/LGFPA6) have been investigated by comparison with the formulation without OMMT (FR/LGFPA6), being dealt with accelerated aging condition. Relative to the unaged composites, both aged composites presented the improved static mechanical properties after 10-day aging, the increased degree of cross-linking in the amorphous region, and the increased LOI value as well as maintained the optimal UL-94 rating. However, after a long-time aging exposure, the aged FR/LGFPA6 composite was more flammable and its mechanical properties were more severely impacted by aging. Remarkably, substitution of a certain content of halogen-antimony flame retardants with OMMT not only slowed down the rate of degradation but also weakened the flammability for FR/LGFPA6 composite over the whole period of aging. POLYM. COMPOS., 40:2208-2218, 2019. (c) 2018 Society of Plastics Engineers}, keywords = {}, pubstate = {published}, tppubtype = {article} } The static and dynamic mechanical properties and fire behaviors for long-glass-fiber reinforced polyamide 6 composite filled with organo-modified montmorillonite/brominated epoxy resins/antimony trioxide (OMMT/FR/LGFPA6) have been investigated by comparison with the formulation without OMMT (FR/LGFPA6), being dealt with accelerated aging condition. Relative to the unaged composites, both aged composites presented the improved static mechanical properties after 10-day aging, the increased degree of cross-linking in the amorphous region, and the increased LOI value as well as maintained the optimal UL-94 rating. However, after a long-time aging exposure, the aged FR/LGFPA6 composite was more flammable and its mechanical properties were more severely impacted by aging. Remarkably, substitution of a certain content of halogen-antimony flame retardants with OMMT not only slowed down the rate of degradation but also weakened the flammability for FR/LGFPA6 composite over the whole period of aging. POLYM. COMPOS., 40:2208-2218, 2019. (c) 2018 Society of Plastics Engineers |
Galiyeva, Perizat; Alem, Halima; Rinnert, Herve; Balan, Lavinia; Blanchard, Sebastien; Medjahdi, Ghouti; Uralbekov, Bolat; Schneider, Raphael Highly fluorescent, color tunable and magnetic quaternary Ag-In-Mn-Zn-S quantum dots (Article de journal) Inorganic Chemistry Frontiers, 6 (6), p. 1422–1431, 2019. @article{Galiyeva2019, title = {Highly fluorescent, color tunable and magnetic quaternary Ag-In-Mn-Zn-S quantum dots}, author = { Perizat Galiyeva and Halima Alem and Herve Rinnert and Lavinia Balan and Sebastien Blanchard and Ghouti Medjahdi and Bolat Uralbekov and Raphael Schneider}, doi = {10.1039/c9qi00131j}, year = {2019}, date = {2019-06-01}, journal = {Inorganic Chemistry Frontiers}, volume = {6}, number = {6}, pages = {1422--1431}, abstract = {Mn-Doped quantum dots (QDs) are of high interest for numerous applications like solar cells, optoelectronics, optosensing, or bioimaging. Here, we report the preparation of quaternary (AgInS2)(x)(MnS)(y)(ZnS)(1-x-y) QDs, thereafter noted Mn : AIZS via a thermally induced decomposition of Ag, In, Zn and Mn precursors in the presence of oleylamine and dodecanethiol. The Mn : AIZS QDs have an average diameter of 3.5 nm and their XRD patterns can be indexed with the orthorhombic phase of AgInS2. The incorporation of Mn2+ ions in the AIZS crystal lattice results in a red-shift of the photoluminescence (PL) emission maximum depending on the Mn2+ content. The PL quantum yields decrease upon loading with Mn2+ but remained high (53-31%) until 50% theoretical loading in Mn2+. Steady state, PL excitation and time-resolved PL measurements suggest that Mn2+-dependent trap states are involved in the PL emission. Mn : AIZS QDs exhibit also magnetic properties. In addition, Mn : AIZS QDs can easily be transferred to the aqueous phase using the PMAO amphiphilic polymer without alteration of their optical properties (PL quantum yield up to 51%), revealing their high potential for biological applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Mn-Doped quantum dots (QDs) are of high interest for numerous applications like solar cells, optoelectronics, optosensing, or bioimaging. Here, we report the preparation of quaternary (AgInS2)(x)(MnS)(y)(ZnS)(1-x-y) QDs, thereafter noted Mn : AIZS via a thermally induced decomposition of Ag, In, Zn and Mn precursors in the presence of oleylamine and dodecanethiol. The Mn : AIZS QDs have an average diameter of 3.5 nm and their XRD patterns can be indexed with the orthorhombic phase of AgInS2. The incorporation of Mn2+ ions in the AIZS crystal lattice results in a red-shift of the photoluminescence (PL) emission maximum depending on the Mn2+ content. The PL quantum yields decrease upon loading with Mn2+ but remained high (53-31%) until 50% theoretical loading in Mn2+. Steady state, PL excitation and time-resolved PL measurements suggest that Mn2+-dependent trap states are involved in the PL emission. Mn : AIZS QDs exhibit also magnetic properties. In addition, Mn : AIZS QDs can easily be transferred to the aqueous phase using the PMAO amphiphilic polymer without alteration of their optical properties (PL quantum yield up to 51%), revealing their high potential for biological applications. |
Dutournie, Patrick; Deon, Sebastien; Limousy, Lionel Understanding the separation of anion mixtures by TiO2 membranes: Numerical investigation and effect of alkaline treatment on physicochemical properties (Article de journal) Chemical Engineering Journal, 363 , p. 365–373, 2019. @article{Dutournie2019, title = {Understanding the separation of anion mixtures by TiO2 membranes: Numerical investigation and effect of alkaline treatment on physicochemical properties}, author = { Patrick Dutournie and Sebastien Deon and Lionel Limousy}, doi = {10.1016/j.cej.2019.01.116}, year = {2019}, date = {2019-05-01}, journal = {Chemical Engineering Journal}, volume = {363}, pages = {365--373}, abstract = {Mechanisms governing the rejection of ions from multi-ionic solutions, and especially the selectivity between various anions are not fully understood at the present time. In this study, it is proposed, in a first part, to investigate the evolution of electric and dielectric exclusion mechanisms when anions are mixed in a solution. For this purpose, the volumetric membrane charge X-d and the dielectric constant of the solution confined within pores epsilon(p) are numerically assessed from rejection curves with a classic transport model. This study highlights that the rejection of the various anions is differently governed by electric and dielectric mechanisms but their contribution to mixture separation seems to be proportionally impacted by the solutions mixed. It was for instance demonstrated that the couple (epsilon(p), X-d) obtained with the ternary salt mixture (NaF-NaI-Na2SO4) corresponds to the barycenter of the triangle made by the couples of the three corresponding binary salt mixtures (i.e. NaF-NaI, NaF-Na2SO4 and NaI-Na2SO4). In a second part, the influence of a mild alkaline treatment, consisting in the filtration of a sodium carbonate solution, is investigated from the variation in membrane charge and dielectric constant assessed from ion mixtures. It is shown that the alkaline treatment mostly diminishes dielectric exclusion through a notable increase in dielectric constant inside pores when solution contains fluoride ion. Membrane charge estimated with solutions containing fluoride ion was found to be slightly impacted, but differently depending on the other anions in solution. Finally, exclusion mechanisms are found to be weak and unaffected by the treatment when solution does not contain fluoride ion.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Mechanisms governing the rejection of ions from multi-ionic solutions, and especially the selectivity between various anions are not fully understood at the present time. In this study, it is proposed, in a first part, to investigate the evolution of electric and dielectric exclusion mechanisms when anions are mixed in a solution. For this purpose, the volumetric membrane charge X-d and the dielectric constant of the solution confined within pores epsilon(p) are numerically assessed from rejection curves with a classic transport model. This study highlights that the rejection of the various anions is differently governed by electric and dielectric mechanisms but their contribution to mixture separation seems to be proportionally impacted by the solutions mixed. It was for instance demonstrated that the couple (epsilon(p), X-d) obtained with the ternary salt mixture (NaF-NaI-Na2SO4) corresponds to the barycenter of the triangle made by the couples of the three corresponding binary salt mixtures (i.e. NaF-NaI, NaF-Na2SO4 and NaI-Na2SO4). In a second part, the influence of a mild alkaline treatment, consisting in the filtration of a sodium carbonate solution, is investigated from the variation in membrane charge and dielectric constant assessed from ion mixtures. It is shown that the alkaline treatment mostly diminishes dielectric exclusion through a notable increase in dielectric constant inside pores when solution contains fluoride ion. Membrane charge estimated with solutions containing fluoride ion was found to be slightly impacted, but differently depending on the other anions in solution. Finally, exclusion mechanisms are found to be weak and unaffected by the treatment when solution does not contain fluoride ion. |
Gerard, Violaine; Ay, Emel; Morlet-Savary, Fabrice; Graff, Bernadette; Galopin, Christophe; Ogren, Thaddao; Mutilangi, William; Lalevee, Jacques Thermal and Photochemical Stability of Anthocyanins from Black Carrot, Grape Juice, and Purple Sweet Potato in Model Beverages in the Presence of Ascorbic Acid (Article de journal) Journal of Agricultural and Food Chemistry, 67 (19), p. 5647–5660, 2019. @article{Gerard2019, title = {Thermal and Photochemical Stability of Anthocyanins from Black Carrot, Grape Juice, and Purple Sweet Potato in Model Beverages in the Presence of Ascorbic Acid}, author = { Violaine Gerard and Emel Ay and Fabrice Morlet-Savary and Bernadette Graff and Christophe Galopin and Thaddao Ogren and William Mutilangi and Jacques Lalevee}, doi = {10.1021/acs.jafc.9b01672}, year = {2019}, date = {2019-05-01}, journal = {Journal of Agricultural and Food Chemistry}, volume = {67}, number = {19}, pages = {5647--5660}, abstract = {Anthocyanins are natural dyes widely used in the food industry, but their chemical stability in beverages can be affected by the presence of additives. In the present paper, the interaction between anthocyanins and ascorbic acid (AA) is more particularly investigated. Ascorbic acid is an ubiquitous component in food products. In this study, the thermal stability at 43 degrees C and the photolysis stability in air and in an inert atmosphere (N-2) of anthocyanins extracted from black carrot (BC), grape juice (GJ), and purple sweet potato (SP) were studied in the presence and absence of ascorbic acid (in citrate buffer at pH 3). Discriminating the main environmental factors (i.e., heat and light) affecting anthocyanin stability is a key point for better understanding the degradation pathways. The stability of the anthocyanins was followed by UV-vis spectrometry. Moreover, to understand the degradation mechanisms in both the presence and absence of ascorbic acid, various techniques such as fluorescence quenching, cyclic voltammetry, and electron-spin-resonance (ESR) spectroscopy were also used to furnish a full coherent picture of the chemical mechanisms associated with the anthocyanin degradation. In addition, molecular orbitals and bond-dissociation energies (BDE) were calculated to extend the investigation. Moreover, the effects of some supplementary stabilizers (chlorogenic acid, sinapic acid, tannic acid, fumaric acid, beta-carotene, isoquercitrin, myricitrin, green coffee bean extract, and rosemary extract) and sugars (sucrose, fructose, and glucose) on anthocyanins stability in the presence of ascorbic acid were examined.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Anthocyanins are natural dyes widely used in the food industry, but their chemical stability in beverages can be affected by the presence of additives. In the present paper, the interaction between anthocyanins and ascorbic acid (AA) is more particularly investigated. Ascorbic acid is an ubiquitous component in food products. In this study, the thermal stability at 43 degrees C and the photolysis stability in air and in an inert atmosphere (N-2) of anthocyanins extracted from black carrot (BC), grape juice (GJ), and purple sweet potato (SP) were studied in the presence and absence of ascorbic acid (in citrate buffer at pH 3). Discriminating the main environmental factors (i.e., heat and light) affecting anthocyanin stability is a key point for better understanding the degradation pathways. The stability of the anthocyanins was followed by UV-vis spectrometry. Moreover, to understand the degradation mechanisms in both the presence and absence of ascorbic acid, various techniques such as fluorescence quenching, cyclic voltammetry, and electron-spin-resonance (ESR) spectroscopy were also used to furnish a full coherent picture of the chemical mechanisms associated with the anthocyanin degradation. In addition, molecular orbitals and bond-dissociation energies (BDE) were calculated to extend the investigation. Moreover, the effects of some supplementary stabilizers (chlorogenic acid, sinapic acid, tannic acid, fumaric acid, beta-carotene, isoquercitrin, myricitrin, green coffee bean extract, and rosemary extract) and sugars (sucrose, fructose, and glucose) on anthocyanins stability in the presence of ascorbic acid were examined. |
Pinot, Matthieu; Lebeau, Benedicte; Nouali, Habiba; Daou, Jean T; Patarin, Joel; Ryzhikov, Andrey High pressure intrusion of water and LiCl aqueous solutions in hydrophobic KIT-6 mesoporous silica: Influence of the grafted group nature (Article de journal) Microporous and Mesoporous Materials, 280 , p. 248–255, 2019. @article{Pinot2019, title = {High pressure intrusion of water and LiCl aqueous solutions in hydrophobic KIT-6 mesoporous silica: Influence of the grafted group nature}, author = { Matthieu Pinot and Benedicte Lebeau and Habiba Nouali and T. Jean Daou and Joel Patarin and Andrey Ryzhikov}, doi = {10.1016/j.micromeso.2019.02.006}, year = {2019}, date = {2019-05-01}, journal = {Microporous and Mesoporous Materials}, volume = {280}, pages = {248--255}, abstract = {High pressure intrusion-extrusion of water and LiCl aqueous solutions in KIT-6 mesoporous silica grafted with alkyl or perfluoroalkyl groups have been studied for absorption of mechanical energy. The "grafted KIT-6 LiCl solution" systems demonstrate a shock absorber behavior with a large hysteresis between intrusion and extrusion curves and partially irreversible intrusion in the first intrusion-extrusion cycle. The samples of KIT-6 with perfluroalkyl grafting demonstrate higher values of intrusion pressure in comparison with ones grafted with alkyl groups, but lower intruded volume. It has been found that the intrusion of LiCl solutions leads to a considerable increase of intrusion pressure, particularly pronounced in the case of the samples grafted with perfluoroalkyl groups. This increase is higher than one expected from the Laplace-Washburn equation. When salt concentration increases, the intrusion becomes more reversible in the case of alkyl grafting, but slightly less in the case of perfluoroalkyl one.}, keywords = {}, pubstate = {published}, tppubtype = {article} } High pressure intrusion-extrusion of water and LiCl aqueous solutions in KIT-6 mesoporous silica grafted with alkyl or perfluoroalkyl groups have been studied for absorption of mechanical energy. The "grafted KIT-6 LiCl solution" systems demonstrate a shock absorber behavior with a large hysteresis between intrusion and extrusion curves and partially irreversible intrusion in the first intrusion-extrusion cycle. The samples of KIT-6 with perfluroalkyl grafting demonstrate higher values of intrusion pressure in comparison with ones grafted with alkyl groups, but lower intruded volume. It has been found that the intrusion of LiCl solutions leads to a considerable increase of intrusion pressure, particularly pronounced in the case of the samples grafted with perfluoroalkyl groups. This increase is higher than one expected from the Laplace-Washburn equation. When salt concentration increases, the intrusion becomes more reversible in the case of alkyl grafting, but slightly less in the case of perfluoroalkyl one. |
Wang, Dengxia; Garra, Patxi; Szillat, Florian; Fouassier, Jean Pierre; Lalevee, Jacques Silane Based Redox Initiating Systems: Toward a Safer Amine-Free, Peroxide-Free, and Metal-Free Approach (Article de journal) Macromolecules, 52 (9), p. 3351–3358, 2019. @article{Wang2019, title = {Silane Based Redox Initiating Systems: Toward a Safer Amine-Free, Peroxide-Free, and Metal-Free Approach}, author = { Dengxia Wang and Patxi Garra and Florian Szillat and Jean Pierre Fouassier and Jacques Lalevee}, doi = {10.1021/acs.macromol.9b00233}, year = {2019}, date = {2019-05-01}, journal = {Macromolecules}, volume = {52}, number = {9}, pages = {3351--3358}, abstract = {Room temperature redox initiated free radical polymerization (RFRP) has always attracted high attention in the field of materials due to its advantages of energy saving, high efficiency, and easy operation. However, the current redox initiating systems are based on toxic aromatic amines and hazardous peroxides (e.g., dibenzoylperoxide). In the present paper, the redox two component (2K) initiating performances of silanes (as reducing agents) in combination with a highly stable iodonium salt (as oxidizing agent) were studied for the first time under mild conditions (RT, under air). Optical pyrometry measurements and DSC investigation results showed that the diphenylsilane (DPS) exhibited a unique initiating property for several (meth)acrylate monomers. Remarkably, thermal postcuring (B-stage) is also possible using this system. Based on electron spin resonance (ESR) experiments, the initiating chemical mechanisms of RFRP are established. Importantly, the new proposed initiating systems can be used for the preparation of tack-free glass fibers and carbon fibers composites at room temperature.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Room temperature redox initiated free radical polymerization (RFRP) has always attracted high attention in the field of materials due to its advantages of energy saving, high efficiency, and easy operation. However, the current redox initiating systems are based on toxic aromatic amines and hazardous peroxides (e.g., dibenzoylperoxide). In the present paper, the redox two component (2K) initiating performances of silanes (as reducing agents) in combination with a highly stable iodonium salt (as oxidizing agent) were studied for the first time under mild conditions (RT, under air). Optical pyrometry measurements and DSC investigation results showed that the diphenylsilane (DPS) exhibited a unique initiating property for several (meth)acrylate monomers. Remarkably, thermal postcuring (B-stage) is also possible using this system. Based on electron spin resonance (ESR) experiments, the initiating chemical mechanisms of RFRP are established. Importantly, the new proposed initiating systems can be used for the preparation of tack-free glass fibers and carbon fibers composites at room temperature. |
Baralle, Alexandre; Garra, Patxi; Graff, Bernadette; Morlet-Savary, Fabrice; Dietlin, Celine; Fouassier, Jean Pierre; Lakhdar, Sami; Lalevee, Jacques Iodinated Polystyrene for Polymeric Charge Transfer Complexes: Toward High-Performance Near-UV and Visible Light Macrophotoinitiators (Article de journal) Macromolecules, 52 (9), p. 3448–3453, 2019. @article{Baralle2019, title = {Iodinated Polystyrene for Polymeric Charge Transfer Complexes: Toward High-Performance Near-UV and Visible Light Macrophotoinitiators}, author = { Alexandre Baralle and Patxi Garra and Bernadette Graff and Fabrice Morlet-Savary and Celine Dietlin and Jean Pierre Fouassier and Sami Lakhdar and Jacques Lalevee}, doi = {10.1021/acs.macromol.9b00252}, year = {2019}, date = {2019-05-01}, journal = {Macromolecules}, volume = {52}, number = {9}, pages = {3448--3453}, abstract = {In recent works, charge transfer complexes (CTCs) have proved to be useful photoinitiating agents to trigger free radical polymerization. However, because of their low molecular weights, migration issues remain very important. In line with pressing migration concerns around photoinitiating systems (e.g., in 3D polymer networks), we report here the use of the first polymeric CTC based on iodinated polystyrene/amine interactions. This study shows the formation of the CTC between the polystyrene derivative (electron acceptor EA) and a tertiary alkylamine (electron donor ED); the ability of this EA/ED couple in a CTC to act as a photoinitiator for the polymerization of multifunctional acrylates upon LED@405 nm irradiation is investigated. Examples of applications to 3D-resolved laser write of thick controlled samples (1 mm) are provided.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In recent works, charge transfer complexes (CTCs) have proved to be useful photoinitiating agents to trigger free radical polymerization. However, because of their low molecular weights, migration issues remain very important. In line with pressing migration concerns around photoinitiating systems (e.g., in 3D polymer networks), we report here the use of the first polymeric CTC based on iodinated polystyrene/amine interactions. This study shows the formation of the CTC between the polystyrene derivative (electron acceptor EA) and a tertiary alkylamine (electron donor ED); the ability of this EA/ED couple in a CTC to act as a photoinitiator for the polymerization of multifunctional acrylates upon LED@405 nm irradiation is investigated. Examples of applications to 3D-resolved laser write of thick controlled samples (1 mm) are provided. |
Dolgopolov, Andrey V; Grafskaia, Kseniia N; Bovsunovskaya, Polina V; Melnikova, Elina R; Ivanov, Dimitri A; Pich, Andrij; Zhu, Xiaomin; Moller, Martin Aqueous microgels modified with photosensitive wedge-shaped amphiphilic molecules: synthesis, structure and photochemical behaviour. (Article de journal) Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology, 2019. @article{Dolgopolov2019, title = {Aqueous microgels modified with photosensitive wedge-shaped amphiphilic molecules: synthesis, structure and photochemical behaviour.}, author = { Andrey V. Dolgopolov and Kseniia N. Grafskaia and Polina V. Bovsunovskaya and Elina R. Melnikova and Dimitri A. Ivanov and Andrij Pich and Xiaomin Zhu and Martin Moller}, doi = {10.1039/c9pp00044e}, year = {2019}, date = {2019-05-01}, journal = {Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology}, abstract = {Aqueous microgels based on poly(N-vinylcaprolactam) with reversible temperature-induced volume transition are promising "smart" materials for various applications. In this work, the microgels are modified via acid-base interaction by wedge-shaped amphiphilic sulfonic acid molecules with alkyl chains of different lengths and an azobenzene group. In contrast to the pristine microgel the modified microgels retain colloidal stability in water and show different responses to the change of temperature and pH. The azobenzene group in the ligand molecules acts as a spectroscopic and kinetic probe sensing the microenvironment inside the microgel particles. Thus, the observed hyperchromicity upon heating suggests the enhancement of hydrophobicity with the increase of temperature. The hydrophobicity of the microgel interior increases with the increase of the modification degree as indicated by the increase of activation energy of the thermal Z/E isomerization of the azobenzene group.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Aqueous microgels based on poly(N-vinylcaprolactam) with reversible temperature-induced volume transition are promising "smart" materials for various applications. In this work, the microgels are modified via acid-base interaction by wedge-shaped amphiphilic sulfonic acid molecules with alkyl chains of different lengths and an azobenzene group. In contrast to the pristine microgel the modified microgels retain colloidal stability in water and show different responses to the change of temperature and pH. The azobenzene group in the ligand molecules acts as a spectroscopic and kinetic probe sensing the microenvironment inside the microgel particles. Thus, the observed hyperchromicity upon heating suggests the enhancement of hydrophobicity with the increase of temperature. The hydrophobicity of the microgel interior increases with the increase of the modification degree as indicated by the increase of activation energy of the thermal Z/E isomerization of the azobenzene group. |
Khadem-Abbassi, Kiana; Rinnert, Herve; Balan, Lavinia; Doumandji, Zahra; Joubert, Olivier; Masteri-Farahani, Majid; Schneider, Raphael CdTe0.5S0.5/ZnS Quantum Dots Embedded in a Molecularly Imprinted Polymer for the Selective Optosensing of Dopamine. (Article de journal) Nanomaterials (Basel, Switzerland), 9 (5), 2019. @article{Khadem-Abbassi2019, title = {CdTe0.5S0.5/ZnS Quantum Dots Embedded in a Molecularly Imprinted Polymer for the Selective Optosensing of Dopamine.}, author = { Kiana Khadem-Abbassi and Herve Rinnert and Lavinia Balan and Zahra Doumandji and Olivier Joubert and Majid Masteri-Farahani and Raphael Schneider}, doi = {10.3390/nano9050693}, year = {2019}, date = {2019-05-01}, journal = {Nanomaterials (Basel, Switzerland)}, volume = {9}, number = {5}, abstract = {This work describes the preparation of molecularly imprinted polymer (MIP)-modified core/shell CdTe0.5S0.5/ZnS quantum dots (QDs). The QDs@MIP particles were used for the selective and sensitive detection of dopamine (DA). Acrylamide, which is able to form hydrogen bonds with DA, and ethylene glycol dimethylacrylate (EGDMA) as cross-linker were used for the preparation of the MIP. Highly cross-linked polymer particles with sizes up to 1 m containing the dots were obtained after the polymerization. After the removal of the DA template, MIP-modified QDs (QDs@MIP) exhibit a high photoluminescence (PL) with an intensity similar to that of QDs embedded in the nonimprinted polymer (NIP). A linear PL decrease was observed upon addition of DA to QDs@MIP and the PL response was in the linear ranges from 2.63 M to 26.30 M with a limit of detection of 6.6 nM. The PL intensity of QDs@MIP was quenched selectively by DA. The QDs@MIP particles developed in this work are easily prepared and of low cost and are therefore of high interest for the sensitive and selective detection of DA in biological samples.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This work describes the preparation of molecularly imprinted polymer (MIP)-modified core/shell CdTe0.5S0.5/ZnS quantum dots (QDs). The QDs@MIP particles were used for the selective and sensitive detection of dopamine (DA). Acrylamide, which is able to form hydrogen bonds with DA, and ethylene glycol dimethylacrylate (EGDMA) as cross-linker were used for the preparation of the MIP. Highly cross-linked polymer particles with sizes up to 1 m containing the dots were obtained after the polymerization. After the removal of the DA template, MIP-modified QDs (QDs@MIP) exhibit a high photoluminescence (PL) with an intensity similar to that of QDs embedded in the nonimprinted polymer (NIP). A linear PL decrease was observed upon addition of DA to QDs@MIP and the PL response was in the linear ranges from 2.63 M to 26.30 M with a limit of detection of 6.6 nM. The PL intensity of QDs@MIP was quenched selectively by DA. The QDs@MIP particles developed in this work are easily prepared and of low cost and are therefore of high interest for the sensitive and selective detection of DA in biological samples. |
Clair, Charles; Lallam, Abdelaziz; Rosenthal, Martin; Sztucki, Michael; Vatankhah-Varnosfaderani, Mohammad; Keith, Andrew N; Cong, Yidan; Liang, Heyi; Dobrynin, Andrey V; Sheiko, Sergei S; Ivanov, Dimitri A Strained Bottlebrushes in Super-Soft Physical Networks (Article de journal) Acs Macro Letters, 8 (5), p. 530–534, 2019. @article{Clair2019, title = {Strained Bottlebrushes in Super-Soft Physical Networks}, author = { Charles Clair and Abdelaziz Lallam and Martin Rosenthal and Michael Sztucki and Mohammad Vatankhah-Varnosfaderani and Andrew N. Keith and Yidan Cong and Heyi Liang and Andrey V. Dobrynin and Sergei S. Sheiko and Dimitri A. Ivanov}, doi = {10.1021/acsmacrolett.9b00106}, year = {2019}, date = {2019-05-01}, journal = {Acs Macro Letters}, volume = {8}, number = {5}, pages = {530--534}, abstract = {ABA triblock copolymers composed of a poly(dimethylsiloxane) (PDMS) bottlebrush central block and linear poly(methyl methacrylate) (PMMA) terminal blocks self assemble into a physical network of PDMS bottlebrush strands connected by PMMA spherical domains. A combination of small- and ultrasmall-angle X-ray scattering techniques was used to concurrently examine dimensions of PMMA spherical domains and PDMS bottlebrush strands both in the bulk and at the PMMA PDMS interface. In agreement with scaling model predictions, the degrees of polymerization of the bottlebrush backbone (n(bb)) and PMMA block (n(A)) correlate with the measured PMMA domain size and area per molecule at the PMMA-PDMS interface as D-A proportional to (n(bb)n(A))(1/3) and S proportional to n(A)(2/3)n(bb)(-1/3), respectively. In the bulk, bottlebrush strands are extended due to steric repulsion between the side chains and unfavorable interactions between the different blocks. At the PMMA-PDMS interface with large curvature, packing constraints require additional bottlebrush backbone extension and alignment of side chains along the backbone in the direction perpendicular to the interface.}, keywords = {}, pubstate = {published}, tppubtype = {article} } ABA triblock copolymers composed of a poly(dimethylsiloxane) (PDMS) bottlebrush central block and linear poly(methyl methacrylate) (PMMA) terminal blocks self assemble into a physical network of PDMS bottlebrush strands connected by PMMA spherical domains. A combination of small- and ultrasmall-angle X-ray scattering techniques was used to concurrently examine dimensions of PMMA spherical domains and PDMS bottlebrush strands both in the bulk and at the PMMA PDMS interface. In agreement with scaling model predictions, the degrees of polymerization of the bottlebrush backbone (n(bb)) and PMMA block (n(A)) correlate with the measured PMMA domain size and area per molecule at the PMMA-PDMS interface as D-A proportional to (n(bb)n(A))(1/3) and S proportional to n(A)(2/3)n(bb)(-1/3), respectively. In the bulk, bottlebrush strands are extended due to steric repulsion between the side chains and unfavorable interactions between the different blocks. At the PMMA-PDMS interface with large curvature, packing constraints require additional bottlebrush backbone extension and alignment of side chains along the backbone in the direction perpendicular to the interface. |
Pichot, V; Guerchoux, M; Muller, O; Guillevic, M; Fioux, P; Merlat, L; Spitzer, D Nanodiamond coating by polyethylenimine for optical limitation (Article de journal) Diamond and Related Materials, 95 , p. 55–59, 2019. @article{Pichot2019, title = {Nanodiamond coating by polyethylenimine for optical limitation}, author = { V. Pichot and M. Guerchoux and O. Muller and M. Guillevic and P. Fioux and L. Merlat and D. Spitzer}, doi = {10.1016/j.diamond.2019.04.001}, year = {2019}, date = {2019-05-01}, journal = {Diamond and Related Materials}, volume = {95}, pages = {55--59}, abstract = {Polyethylenimine (PEI) is used to elaborate detonation nanodiamonds coated with a polymer material. Evolution of the nanodiamonds surface charge depending on the PEI concentration is revealed by a zeta potential study. While the surface charge of the nanodiamond is negative due to its oxygenated functional groups, the cationic polymer allows reversing it to a positive one. Spectroscopy characterizations are used to investigate the PEI interaction with the nanodiamonds and to estimate the very small thickness of the PEI layer on the nanodiamonds surface. The oxygenated functional groups of the nanoparticles interact electrostatically with the PEI amine groups. The good performances of the non-linear optical properties of this material are demonstrated at a wavelength of 1064 nm.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Polyethylenimine (PEI) is used to elaborate detonation nanodiamonds coated with a polymer material. Evolution of the nanodiamonds surface charge depending on the PEI concentration is revealed by a zeta potential study. While the surface charge of the nanodiamond is negative due to its oxygenated functional groups, the cationic polymer allows reversing it to a positive one. Spectroscopy characterizations are used to investigate the PEI interaction with the nanodiamonds and to estimate the very small thickness of the PEI layer on the nanodiamonds surface. The oxygenated functional groups of the nanoparticles interact electrostatically with the PEI amine groups. The good performances of the non-linear optical properties of this material are demonstrated at a wavelength of 1064 nm. |
Anfar, Z; Zbair, M; Ahsaine, H A; Abdellaoui, Y; Fakir, El A A; Amaterz, E; Jada, A; Alem, El N Preparation and Characterization of Porous Carbon@ZnO-NPs for Organic Compounds Removal: Classical Adsorption Versus Ultrasound Assisted Adsorption (Article de journal) Chemistryselect, 4 (17), p. 4981–4994, 2019. @article{Anfar2019, title = {Preparation and Characterization of Porous Carbon@ZnO-NPs for Organic Compounds Removal: Classical Adsorption Versus Ultrasound Assisted Adsorption}, author = { Z. Anfar and M. Zbair and H. A. Ahsaine and Y. Abdellaoui and A. A. El Fakir and E. Amaterz and A. Jada and N. El Alem}, doi = {10.1002/slct.201901043}, year = {2019}, date = {2019-05-01}, journal = {Chemistryselect}, volume = {4}, number = {17}, pages = {4981--4994}, abstract = {In this paper, the synthesis and characterization of porous carbon (PC) and porous carbon loaded ZnO nanoparticles (PC@ZnO) were investigated. The removal efficiency of Methylene Blue (MB) under ultrasound waves (UAA) and without ultrasound waves (SA) was studied considering the adsorbents dose, contact time, solution pH, temperature and initial dye concentration. Ultrasound irradiation have a positive effect on the removal efficiency of MB whereas ZnO nanoparticles incorporate in the surface of PC improve the regeneration efficiency of PC. PC@ZnO NPs shows high performance of MB removal using UAA, which was used for simultaneous removal of Crystal Violet (CV) and Congo Red (CR). The ultrasonic adsorption of CV/CR on PC@ZnO was found to be dependent on different parameters such as contact time, solution pH and initial dye concentration. The experimental results were found to follow the pseudo-second-order and Langmuir models. The adsorbed amount was found to be 64mg g(-1) (for CR) and 109mg g(-1) (for CV). Further, the effects of various parameters such as contact time, pH, initial dye concentration, and CV:CR ratio, were studied using central composite design coupled with response surface methodology. The data showed that the PC@ZnO has strong selective adsorption of CV dye in comparison to CR, and optimum conditions were found to be natural pH, 11.19mg, (55:45%) of CV:CR ratio, 25min and 30mg L-1 at adsorption temperature T=25 degrees C +/- 1. In these conditions, both dyes (CV and CR) are easily regenerated using HCl (0.1M).}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this paper, the synthesis and characterization of porous carbon (PC) and porous carbon loaded ZnO nanoparticles (PC@ZnO) were investigated. The removal efficiency of Methylene Blue (MB) under ultrasound waves (UAA) and without ultrasound waves (SA) was studied considering the adsorbents dose, contact time, solution pH, temperature and initial dye concentration. Ultrasound irradiation have a positive effect on the removal efficiency of MB whereas ZnO nanoparticles incorporate in the surface of PC improve the regeneration efficiency of PC. PC@ZnO NPs shows high performance of MB removal using UAA, which was used for simultaneous removal of Crystal Violet (CV) and Congo Red (CR). The ultrasonic adsorption of CV/CR on PC@ZnO was found to be dependent on different parameters such as contact time, solution pH and initial dye concentration. The experimental results were found to follow the pseudo-second-order and Langmuir models. The adsorbed amount was found to be 64mg g(-1) (for CR) and 109mg g(-1) (for CV). Further, the effects of various parameters such as contact time, pH, initial dye concentration, and CV:CR ratio, were studied using central composite design coupled with response surface methodology. The data showed that the PC@ZnO has strong selective adsorption of CV dye in comparison to CR, and optimum conditions were found to be natural pH, 11.19mg, (55:45%) of CV:CR ratio, 25min and 30mg L-1 at adsorption temperature T=25 degrees C +/- 1. In these conditions, both dyes (CV and CR) are easily regenerated using HCl (0.1M). |
Deon, Sebastien; Koubaa, Zakaryae; Korzhova, Elizaveta; Airoudj, Aissam; Fievet, Patrick; Roucoules, Vincent Understanding the impact of poly(allylamine) plasma grafting on the filtration performances of a commercial polymeric membrane (Article de journal) Separation and Purification Technology, 212 , p. 30–39, 2019. @article{Deon2019, title = {Understanding the impact of poly(allylamine) plasma grafting on the filtration performances of a commercial polymeric membrane}, author = { Sebastien Deon and Zakaryae Koubaa and Elizaveta Korzhova and Aissam Airoudj and Patrick Fievet and Vincent Roucoules}, doi = {10.1016/j.seppur.2018.11.004}, year = {2019}, date = {2019-04-01}, journal = {Separation and Purification Technology}, volume = {212}, pages = {30--39}, abstract = {Commercial membranes often exhibit difficulties in rejecting specific ionic species, and especially multivalent cations, due to their usual negative charge. To face this drawback, it is proposed here to functionalize the membrane surface by allylamine plasma polymerization. The impact of this modification on both permeation flux and ion rejection is investigated for single salt solutions and ion mixtures. It is shown that the membrane behaves like a positive membrane from the point of view of cation rejection but the negative charge (and the corresponding electrical field) inside pores leads to high rejection of divalent anions like a negative membrane. This allows a high selectivity between divalent and monovalent ions irrespective of their sign. However, in the cases of ionic mixtures, the selectivity between cations and anions is reduced as the grafting duration increases. This outstanding impact on performances was obtained although the membrane surface is perhaps partially covered by plasma poly(allylamine). Indeed, the overall apparent zeta-potential was found to be still slightly negative or slightly positive for 5 and 10 min of polymerization, respectively. Consequently, a definitive conclusion about the mechanisms governing the impact of grafting on rejection cannot still be drawn and it requires an in-depth characterization of the membrane before and after modification so as to consider the changes in physicochemical properties induced by poly(allylamine) grafting.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Commercial membranes often exhibit difficulties in rejecting specific ionic species, and especially multivalent cations, due to their usual negative charge. To face this drawback, it is proposed here to functionalize the membrane surface by allylamine plasma polymerization. The impact of this modification on both permeation flux and ion rejection is investigated for single salt solutions and ion mixtures. It is shown that the membrane behaves like a positive membrane from the point of view of cation rejection but the negative charge (and the corresponding electrical field) inside pores leads to high rejection of divalent anions like a negative membrane. This allows a high selectivity between divalent and monovalent ions irrespective of their sign. However, in the cases of ionic mixtures, the selectivity between cations and anions is reduced as the grafting duration increases. This outstanding impact on performances was obtained although the membrane surface is perhaps partially covered by plasma poly(allylamine). Indeed, the overall apparent zeta-potential was found to be still slightly negative or slightly positive for 5 and 10 min of polymerization, respectively. Consequently, a definitive conclusion about the mechanisms governing the impact of grafting on rejection cannot still be drawn and it requires an in-depth characterization of the membrane before and after modification so as to consider the changes in physicochemical properties induced by poly(allylamine) grafting. |
Zazou, Hicham; Afanga, Hanane; Akhouairi, Siham; Ouchtak, Hassan; Addi, Abdelaziz Ait; Akbour, Rachid Ait; Assabbane, Ali; Douch, Jamaa; Elmchaouri, Abdellah; Duplay, Joelle; Jada, Amane; Hamdani, Mohamed Treatment of textile industry wastewater by electrocoagulation coupled with electrochemical advanced oxidation process (Article de journal) Journal of Water Process Engineering, 28 , p. 214–221, 2019. @article{Zazou2019, title = {Treatment of textile industry wastewater by electrocoagulation coupled with electrochemical advanced oxidation process}, author = { Hicham Zazou and Hanane Afanga and Siham Akhouairi and Hassan Ouchtak and Abdelaziz Ait Addi and Rachid Ait Akbour and Ali Assabbane and Jamaa Douch and Abdellah Elmchaouri and Joelle Duplay and Amane Jada and Mohamed Hamdani}, doi = {10.1016/j.jwpe.2019.02.006}, year = {2019}, date = {2019-04-01}, journal = {Journal of Water Process Engineering}, volume = {28}, pages = {214--221}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Anokhin, Denis V; Grafskaia, Kseniia N; Izdelieva, Inessa A; Zhu, Xiaomin; Ivanov, Dimitri A Polymer conformation in supramolecular complexes with wedge-shaped ligands: Exploring the impact of the liquid-crystalline organization (Article de journal) Polymer, 170 , p. 142–147, 2019. @article{Anokhin2019, title = {Polymer conformation in supramolecular complexes with wedge-shaped ligands: Exploring the impact of the liquid-crystalline organization}, author = { Denis V Anokhin and Kseniia N. Grafskaia and Inessa A. Izdelieva and Xiaomin Zhu and Dimitri A. Ivanov}, doi = {10.1016/j.polymer.2019.03.020}, year = {2019}, date = {2019-04-01}, journal = {Polymer}, volume = {170}, pages = {142--147}, abstract = {The chain conformation of poly(2-vinylpyridine) (P2VP) complexed by 4-((4-4((3,4,5-tris(dodecyloxy)benzoyl) oxy)phenyl)diazenyl)benzenesulfonic acid at different degrees of neutralization (DN) was addressed by small-and wide-angle neutron scattering technique. To get information on the conformation of P2VP chains spatially confined within lamellar and columnar mesophases at different DNs, the complexes were prepared from a blend of protonated and deuterated P2VP. The 2D scattering patterns of extruded fibers show that at low DN the complex self-organizes in a lamellar phase. The inertial mean distances in the direction parallel and perpendicular to the fiber axis reveal the formation of compact disc-like globules of individual P2VP chains at DN = 25 and 33%. With the increase of DN the interaction between the neighboring side groups along the backbone increases. This results in formation of hexagonal columnar phase at DN = 50%, in which the P2VP macromolecules are confined within cylindrical channels forming most probably a disordered helical conformation. At DN = 1.0, the enhanced rigidity of the complex hinders the accommodation of the ligands at the interface with polymer chain. This results in appearance of non-bonded side groups in the columns giving rise to a poorly-ordered structure. In contrast to more rigid chains of poly(4-vinylpyridine), the transition from lamellar to columnar mesophase in P2VP occurs at lower DNs, indicating a significant role of the chain flexibility in the formation of ordered structures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The chain conformation of poly(2-vinylpyridine) (P2VP) complexed by 4-((4-4((3,4,5-tris(dodecyloxy)benzoyl) oxy)phenyl)diazenyl)benzenesulfonic acid at different degrees of neutralization (DN) was addressed by small-and wide-angle neutron scattering technique. To get information on the conformation of P2VP chains spatially confined within lamellar and columnar mesophases at different DNs, the complexes were prepared from a blend of protonated and deuterated P2VP. The 2D scattering patterns of extruded fibers show that at low DN the complex self-organizes in a lamellar phase. The inertial mean distances in the direction parallel and perpendicular to the fiber axis reveal the formation of compact disc-like globules of individual P2VP chains at DN = 25 and 33%. With the increase of DN the interaction between the neighboring side groups along the backbone increases. This results in formation of hexagonal columnar phase at DN = 50%, in which the P2VP macromolecules are confined within cylindrical channels forming most probably a disordered helical conformation. At DN = 1.0, the enhanced rigidity of the complex hinders the accommodation of the ligands at the interface with polymer chain. This results in appearance of non-bonded side groups in the columns giving rise to a poorly-ordered structure. In contrast to more rigid chains of poly(4-vinylpyridine), the transition from lamellar to columnar mesophase in P2VP occurs at lower DNs, indicating a significant role of the chain flexibility in the formation of ordered structures. |
Trinh, Thi Kim Hoang; Malval, Jean-Pierre; Morlet-Savary, Fabrice; Pinaud, Julien; Lacroix-Desmazes, Patrick; Reibel, Corine; Heroguez, Valerie; Chemtob, Abraham Mixture of Azolium Tetraphenylborate with Isopropylthioxanthone: a New Class of N-Heterocyclic Carbene (NHC) Photogenerator for Polyurethane, Polyester and ROMP Polymers Synthesis. (Article de journal) Chemistry (Weinheim an der Bergstrasse, Germany), 2019. @article{Trinh2019, title = {Mixture of Azolium Tetraphenylborate with Isopropylthioxanthone: a New Class of N-Heterocyclic Carbene (NHC) Photogenerator for Polyurethane, Polyester and ROMP Polymers Synthesis.}, author = { Thi Kim Hoang Trinh and Jean-Pierre Malval and Fabrice Morlet-Savary and Julien Pinaud and Patrick Lacroix-Desmazes and Corine Reibel and Valerie Heroguez and Abraham Chemtob}, doi = {10.1002/chem.201901000}, year = {2019}, date = {2019-04-01}, journal = {Chemistry (Weinheim an der Bergstrasse, Germany)}, abstract = {In the search of smarter routes to control the conditions of N-heterocyclic carbenes (NHCs) formation, a two-component air-stable NHC photogenerating system is reported. It relies on the irradiation at 365 nm of a mixture of 2-isopropylthioxanthone (ITX) with 1,3-bis(mesityl)imidazoli(ni)um tetraphenylborate. The photoinduced liberation of NHC is evidenced by reaction with a mesitoyl radical to form a NHC-radical adduct detectable by electron spin resonance spectroscopy. The NHC yield can be determined by 1H NMR through the formation of a soluble and stable NHC-carbodiimide adduct. To deprotonate the azolium salt and liberate the NHC, a mechanism is proposed where the role of base is played by ITX radical anion formed in situ by a primary photoinduced electron-transfer reaction between electronically excited ITX (oxidant) and BPh4- (reductant). A NHC yield as high as 70 % is achieved upon starting with a stoichiometric ratio of ITX and azolium salt. Three different photoNHC-mediated polymerizations are described: synthesis of polyurethane and polyester by organocatalyzed step-growth polymerization and ring-opening copolymerization, respectively, and generation of polynorbornene by ring-opening metathesis polymerization using a NHC-coordinated Ru catalyst formed in situ.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In the search of smarter routes to control the conditions of N-heterocyclic carbenes (NHCs) formation, a two-component air-stable NHC photogenerating system is reported. It relies on the irradiation at 365 nm of a mixture of 2-isopropylthioxanthone (ITX) with 1,3-bis(mesityl)imidazoli(ni)um tetraphenylborate. The photoinduced liberation of NHC is evidenced by reaction with a mesitoyl radical to form a NHC-radical adduct detectable by electron spin resonance spectroscopy. The NHC yield can be determined by 1H NMR through the formation of a soluble and stable NHC-carbodiimide adduct. To deprotonate the azolium salt and liberate the NHC, a mechanism is proposed where the role of base is played by ITX radical anion formed in situ by a primary photoinduced electron-transfer reaction between electronically excited ITX (oxidant) and BPh4- (reductant). A NHC yield as high as 70 % is achieved upon starting with a stoichiometric ratio of ITX and azolium salt. Three different photoNHC-mediated polymerizations are described: synthesis of polyurethane and polyester by organocatalyzed step-growth polymerization and ring-opening copolymerization, respectively, and generation of polynorbornene by ring-opening metathesis polymerization using a NHC-coordinated Ru catalyst formed in situ. |
Lai, H; Lu, M; Chen, F; Lalevee, J; Stenzel, M H; Xiao, P Amphiphilic polymer coated nanodiamonds: a promising platform to deliver azonafide (Article de journal) Polymer Chemistry, 10 (15), p. 1904–1911, 2019. @article{Lai2019, title = {Amphiphilic polymer coated nanodiamonds: a promising platform to deliver azonafide}, author = { H. Lai and M. Lu and F. Chen and J. Lalevee and M. H. Stenzel and P. Xiao}, doi = {10.1039/c9py00055k}, year = {2019}, date = {2019-04-01}, journal = {Polymer Chemistry}, volume = {10}, number = {15}, pages = {1904--1911}, abstract = {Nanodiamonds (NDs) are attracting increasing attention as drug delivery systems due to their outstanding mechanical and optical properties as well as excellent biocompatibility. However, the strong tendency to agglomerate limits their use in biological medium, especially when adsorbed hydrophobic compounds. Polymer coating is a convenient approach to enhance the colloidal stability and place therapeutic drugs. Here, we report an epoxy containing amphiphilic block copolymer poly(n-butyl methacrylate-co-poly-glycidol methacrylate-block-poly(oligoethylene glycol methyl ether methacrylate)) (PBA-co-PGA-b-POEGMEMA) for coating NDs. The resultant polymer coating significantly reduced the particle size and enhanced the colloidal stability. The inner hydrophobic block was exploited to encapsulate hydrophobic anticancer drug-azonafide. The cytotoxicity of the azonafide-loaded NDs was evaluated by 2D and 3D models. Although azonafide encapsulation displayed higher IC50 than free azonafide in the 2D breast tumour cell culture model, the former showed accelerated cytotoxicity than free azonafide in the 3D breast multicellular tumour spheroids. The results indicate the amphiphilic polymer coated NDs could be a promising carrier for azonafide due to the facile synthesis protocol, the potential to reduce side effects and the enhanced toxicity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Nanodiamonds (NDs) are attracting increasing attention as drug delivery systems due to their outstanding mechanical and optical properties as well as excellent biocompatibility. However, the strong tendency to agglomerate limits their use in biological medium, especially when adsorbed hydrophobic compounds. Polymer coating is a convenient approach to enhance the colloidal stability and place therapeutic drugs. Here, we report an epoxy containing amphiphilic block copolymer poly(n-butyl methacrylate-co-poly-glycidol methacrylate-block-poly(oligoethylene glycol methyl ether methacrylate)) (PBA-co-PGA-b-POEGMEMA) for coating NDs. The resultant polymer coating significantly reduced the particle size and enhanced the colloidal stability. The inner hydrophobic block was exploited to encapsulate hydrophobic anticancer drug-azonafide. The cytotoxicity of the azonafide-loaded NDs was evaluated by 2D and 3D models. Although azonafide encapsulation displayed higher IC50 than free azonafide in the 2D breast tumour cell culture model, the former showed accelerated cytotoxicity than free azonafide in the 3D breast multicellular tumour spheroids. The results indicate the amphiphilic polymer coated NDs could be a promising carrier for azonafide due to the facile synthesis protocol, the potential to reduce side effects and the enhanced toxicity. |
Khiari, Besma; Massoudi, Marwa; Jeguirim, Mejdi Tunisian tomato waste pyrolysis: thermogravimetry analysis and kinetic study. (Article de journal) Environmental science and pollution research international, 2019. @article{Khiari2019c, title = {Tunisian tomato waste pyrolysis: thermogravimetry analysis and kinetic study.}, author = { Besma Khiari and Marwa Massoudi and Mejdi Jeguirim}, doi = {10.1007/s11356-019-04675-4}, year = {2019}, date = {2019-04-01}, journal = {Environmental science and pollution research international}, abstract = {This paper aims to set up viable units of thermal processing of numerous agricultural wastes in a sustainable development and eco-friendly approach that could create new economic profitable circuits in an increasingly competitive context. One of the most problematic food wastes are tomato processing by-products; concentrating and canning industrial activities generate important amounts of them, particularly in the Tunisian context. As no reference was found in literature dealing with these last residues, this work intended to explore their potential as biomass fuels. Pyrolysis is then applied in thermogravimetric conditions for different heating rates (5, 10, 20, and 30°C/min) in order to recover energy on one hand and to extract the corresponding kinetic parameters for an accurate design of reactors on the other hand. Main results include suitability of the tomato residues to a thermal valorization thanks to high contents of volatiles and fixed carbon and low ash percentage as well as an interesting heating value comparable to lignocellulosic biomass. Mass loss profiles indicate consecutive and overlapping stages of drying, active pyrolysis, and passive pyrolysis. The experimental profiles of conversion rate were well fitted by the three isoconversional methods; the best fitting is recorded by the Flynn-Wall-Ozawa associated with a first-order model for the intermediate pyrolysis and with a contracted sphere (n=1/3) for the slowest studied pyrolysis.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper aims to set up viable units of thermal processing of numerous agricultural wastes in a sustainable development and eco-friendly approach that could create new economic profitable circuits in an increasingly competitive context. One of the most problematic food wastes are tomato processing by-products; concentrating and canning industrial activities generate important amounts of them, particularly in the Tunisian context. As no reference was found in literature dealing with these last residues, this work intended to explore their potential as biomass fuels. Pyrolysis is then applied in thermogravimetric conditions for different heating rates (5, 10, 20, and 30°C/min) in order to recover energy on one hand and to extract the corresponding kinetic parameters for an accurate design of reactors on the other hand. Main results include suitability of the tomato residues to a thermal valorization thanks to high contents of volatiles and fixed carbon and low ash percentage as well as an interesting heating value comparable to lignocellulosic biomass. Mass loss profiles indicate consecutive and overlapping stages of drying, active pyrolysis, and passive pyrolysis. The experimental profiles of conversion rate were well fitted by the three isoconversional methods; the best fitting is recorded by the Flynn-Wall-Ozawa associated with a first-order model for the intermediate pyrolysis and with a contracted sphere (n=1/3) for the slowest studied pyrolysis. |
Kiener, Julien; Limousy, Lionel; Jeguirim, Mejdi; Meins, Jean-Marc Le; Hajjar-Garreau, Samar; Bigoin, Gaetan; Ghimbeu, Camelia Matei Activated Carbon/Transition Metal (Ni, In, Cu) Hexacyanoferrate Nanocomposites for Cesium Adsorption (Article de journal) Materials, 12 (8), p. 1253, 2019. @article{Kiener2019, title = {Activated Carbon/Transition Metal (Ni, In, Cu) Hexacyanoferrate Nanocomposites for Cesium Adsorption}, author = { Julien Kiener and Lionel Limousy and Mejdi Jeguirim and Jean-Marc Le Meins and Samar Hajjar-Garreau and Gaetan Bigoin and Camelia Matei Ghimbeu}, doi = {10.3390/ma12081253}, year = {2019}, date = {2019-04-01}, journal = {Materials}, volume = {12}, number = {8}, pages = {1253}, abstract = {Transition metal hexacyanoferrate/microporous activated carbon composites were obtained using a simple successive impregnation approach. The effect of metal type (nickel, indium, or copper), and the carbon oxidation on the composite characteristics (porosity, metal structure, and particle size), as well as on the removal efficiency of cesium from aqueous solution was investigated. Successful formation of the desired metal hexacyanoferrate phase was achieved and the size of the metallic nanoparticles and their dispersion in the carbon network was found to depend on the metal type, with the indium and nickel-based materials exhibiting the smallest particle size distribution (< 10 nm). Adsorption tests performed under batch conditions demonstrate that the copper hexacyanoferrate/activated carbon composite present the highest cesium removal capacity from aqueous solution (74.7 mgg(-1)) among the three studied metal-based nanocomposites. The carbon oxidation treatment leads to the increase in the number of functional groups to the detriment of the porosity but allows for an improvement in the Cs adsorption capacity. This indicates that the Cs adsorption process is governed by the carbon surface chemistry and not its porosity. Moreover, combining oxidized carbon support with copper hexacyanoferrate induces the highest cesium adsorption capacity (101.5 mgg(-1)). This could be related to synergistic effects through two absorption mechanisms, i.e., a cation exchange mechanism of Cs with the metallic hexacyanoferrate phase and Cs adsorption via carbon oxygen surface groups, as demonstrated using X-ray photoelectron spectroscopy (XPS) analyses.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Transition metal hexacyanoferrate/microporous activated carbon composites were obtained using a simple successive impregnation approach. The effect of metal type (nickel, indium, or copper), and the carbon oxidation on the composite characteristics (porosity, metal structure, and particle size), as well as on the removal efficiency of cesium from aqueous solution was investigated. Successful formation of the desired metal hexacyanoferrate phase was achieved and the size of the metallic nanoparticles and their dispersion in the carbon network was found to depend on the metal type, with the indium and nickel-based materials exhibiting the smallest particle size distribution (< 10 nm). Adsorption tests performed under batch conditions demonstrate that the copper hexacyanoferrate/activated carbon composite present the highest cesium removal capacity from aqueous solution (74.7 mgg(-1)) among the three studied metal-based nanocomposites. The carbon oxidation treatment leads to the increase in the number of functional groups to the detriment of the porosity but allows for an improvement in the Cs adsorption capacity. This indicates that the Cs adsorption process is governed by the carbon surface chemistry and not its porosity. Moreover, combining oxidized carbon support with copper hexacyanoferrate induces the highest cesium adsorption capacity (101.5 mgg(-1)). This could be related to synergistic effects through two absorption mechanisms, i.e., a cation exchange mechanism of Cs with the metallic hexacyanoferrate phase and Cs adsorption via carbon oxygen surface groups, as demonstrated using X-ray photoelectron spectroscopy (XPS) analyses. |
Evariste, Lauris; Lagier, Laura; Gonzalez, Patrice; Mottier, Antoine; Mouchet, Florence; Cadarsi, Stephanie; Lonchambon, Pierre; Daffe, Guillemine; Chimowa, George; Sarrieu, Cyril; Ompraret, Elise; Galibert, Anne-Marie; Ghimbeu, Camelia Matei; Pinelli, Eric; Flahaut, Emmanuel; Gauthier, Laury Thermal Reduction of Graphene Oxide Mitigates Its In Vivo Genotoxicity Toward Xenopus laevis Tadpoles (Article de journal) Nanomaterials, 9 (4), p. 584, 2019. @article{Evariste2019, title = {Thermal Reduction of Graphene Oxide Mitigates Its In Vivo Genotoxicity Toward Xenopus laevis Tadpoles}, author = { Lauris Evariste and Laura Lagier and Patrice Gonzalez and Antoine Mottier and Florence Mouchet and Stephanie Cadarsi and Pierre Lonchambon and Guillemine Daffe and George Chimowa and Cyril Sarrieu and Elise Ompraret and Anne-Marie Galibert and Camelia Matei Ghimbeu and Eric Pinelli and Emmanuel Flahaut and Laury Gauthier}, doi = {10.3390/nano9040584}, year = {2019}, date = {2019-04-01}, journal = {Nanomaterials}, volume = {9}, number = {4}, pages = {584}, abstract = {The worldwide increase of graphene family materials raises the question of the potential consequences resulting from their release in the environment and future consequences on ecosystem health, especially in the aquatic environment in which they are likely to accumulate. Thus, there is a need to evaluate the biological and ecological risk but also to find innovative solutions leading to the production of safer materials. This work focuses on the evaluation of functional group-safety relationships regarding to graphene oxide (GO) in vivo genotoxic potential toward X. laevis tadpoles. For this purpose, thermal treatments in H-2 atmosphere were applied to produce reduced graphene oxide (rGOs) with different surface group compositions. Analysis performed indicated that GO induced disturbances in erythrocyte cell cycle leading to accumulation of cells in G0/G1 phase. Significant genotoxicity due to oxidative stress was observed in larvae exposed to low GO concentration (0.1 mgL(-1)). Reduction of GO at 200 degrees C and 1000 degrees C produced a material that was no longer genotoxic at low concentrations. X-ray photoelectron spectroscopy (XPS) analysis indicated that epoxide groups may constitute a good candidate to explain the genotoxic potential of the most oxidized form of the material. Thermal reduction of GO may constitute an appropriate safer-by-design strategy for the development of a safer material for environment.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The worldwide increase of graphene family materials raises the question of the potential consequences resulting from their release in the environment and future consequences on ecosystem health, especially in the aquatic environment in which they are likely to accumulate. Thus, there is a need to evaluate the biological and ecological risk but also to find innovative solutions leading to the production of safer materials. This work focuses on the evaluation of functional group-safety relationships regarding to graphene oxide (GO) in vivo genotoxic potential toward X. laevis tadpoles. For this purpose, thermal treatments in H-2 atmosphere were applied to produce reduced graphene oxide (rGOs) with different surface group compositions. Analysis performed indicated that GO induced disturbances in erythrocyte cell cycle leading to accumulation of cells in G0/G1 phase. Significant genotoxicity due to oxidative stress was observed in larvae exposed to low GO concentration (0.1 mgL(-1)). Reduction of GO at 200 degrees C and 1000 degrees C produced a material that was no longer genotoxic at low concentrations. X-ray photoelectron spectroscopy (XPS) analysis indicated that epoxide groups may constitute a good candidate to explain the genotoxic potential of the most oxidized form of the material. Thermal reduction of GO may constitute an appropriate safer-by-design strategy for the development of a safer material for environment. |
Boumaiza, Hella; Renard, Aurelien; Robinson, Mbolantenaina Rakotomalala; Kervern, Gwendal; Vidal, Loic; Ruby, Christian; Bergaoui, Latifa; Coustel, Romain A multi-technique approach for studying Na triclinic and hexagonal birnessites (Article de journal) Journal of Solid State Chemistry, 272 , p. 234–243, 2019. @article{Boumaiza2019, title = {A multi-technique approach for studying Na triclinic and hexagonal birnessites}, author = { Hella Boumaiza and Aurelien Renard and Mbolantenaina Rakotomalala Robinson and Gwendal Kervern and Loic Vidal and Christian Ruby and Latifa Bergaoui and Romain Coustel}, doi = {10.1016/j.jssc.2019.02.017}, year = {2019}, date = {2019-04-01}, journal = {Journal of Solid State Chemistry}, volume = {272}, pages = {234--243}, abstract = {Bimessite is a ubiquitous natural Mn oxide. This layered material is involved in a large variety of ion-exchange and redox reaction in soils and sediments. Synthetic Na-triclinic birnessite with a general formula [Mn-0.35(III) Mn-0.65(IV) O-2] [Na-0.35(+) 0.7H(2)O] was converted into hexagonal birnessite by acidic treatment at pH = 3.5. Both solids were fully characterized by TEM, SEM, PXRD, FTIR, Raman scattering, Na-23 as well as the first H-1 MAS NMR birnessite spectra were reported. The surfaces of both forms were fully analyzed by XPS: a particular attention was paid to the determination of the oxidation state of Mn derived from the fitting of XPS Mn 3p or Mn 2p(3/2) features. An excess of reduced Mn at the surface in comparison to the bulk materials was evidenced.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Bimessite is a ubiquitous natural Mn oxide. This layered material is involved in a large variety of ion-exchange and redox reaction in soils and sediments. Synthetic Na-triclinic birnessite with a general formula [Mn-0.35(III) Mn-0.65(IV) O-2] [Na-0.35(+) 0.7H(2)O] was converted into hexagonal birnessite by acidic treatment at pH = 3.5. Both solids were fully characterized by TEM, SEM, PXRD, FTIR, Raman scattering, Na-23 as well as the first H-1 MAS NMR birnessite spectra were reported. The surfaces of both forms were fully analyzed by XPS: a particular attention was paid to the determination of the oxidation state of Mn derived from the fitting of XPS Mn 3p or Mn 2p(3/2) features. An excess of reduced Mn at the surface in comparison to the bulk materials was evidenced. |
Andrei, Radu Dorin; Cambruzzi, Nathan; Bonne, Magali; Lebeau, Benedicte; Hulea, Vasile Selective sulfoxidation reactions with H2O2 catalyzed by Ti-containing SBA-15 materials (Article de journal) Journal of Porous Materials, 26 (2), p. 533–539, 2019. @article{Andrei2019, title = {Selective sulfoxidation reactions with H2O2 catalyzed by Ti-containing SBA-15 materials}, author = { Radu Dorin Andrei and Nathan Cambruzzi and Magali Bonne and Benedicte Lebeau and Vasile Hulea}, doi = {10.1007/s10934-018-0640-1}, year = {2019}, date = {2019-04-01}, journal = {Journal of Porous Materials}, volume = {26}, number = {2}, pages = {533--539}, abstract = {This contribution relates the behavior of Ti-SBA-15 catalysts in the sulfoxidation reaction with hydrogen peroxide under mild conditions (40-70 degrees C). Ti-SBA-15 samples with 1, 3 and 5wt% of TiO2 have been prepared by grafting SBA-15 silica with Ti((OPr)-Pr-i)(4) in ethanol followed by calcination. Due to their mesopores, the Ti-containing catalysts accommodated large molecules like methyl-phenyl-sulfide, diphenylsulfide and dibenzothiophene, which were selectively oxidized into their corresponding sulfoxides and sulfones. The turnover frequency was correlated with the amount of the tetrahedral Ti atoms in the catalyst. During the oxidation process performed in batch mode, with acetonitrile or ethanol as solvent, the catalyst topology and texture were preserved, but the nature of the Ti species suffered some changes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This contribution relates the behavior of Ti-SBA-15 catalysts in the sulfoxidation reaction with hydrogen peroxide under mild conditions (40-70 degrees C). Ti-SBA-15 samples with 1, 3 and 5wt% of TiO2 have been prepared by grafting SBA-15 silica with Ti((OPr)-Pr-i)(4) in ethanol followed by calcination. Due to their mesopores, the Ti-containing catalysts accommodated large molecules like methyl-phenyl-sulfide, diphenylsulfide and dibenzothiophene, which were selectively oxidized into their corresponding sulfoxides and sulfones. The turnover frequency was correlated with the amount of the tetrahedral Ti atoms in the catalyst. During the oxidation process performed in batch mode, with acetonitrile or ethanol as solvent, the catalyst topology and texture were preserved, but the nature of the Ti species suffered some changes. |
Eren, Tugce Nur; Graff, Bernadette; Lalevee, Jacques; Avci, Duygu Thioxanthone-functionalized 1,6-heptadiene as monomeric photoinitiator (Article de journal) Progress in Organic Coatings, 128 , p. 148–156, 2019. @article{Eren2019, title = {Thioxanthone-functionalized 1,6-heptadiene as monomeric photoinitiator}, author = { Tugce Nur Eren and Bernadette Graff and Jacques Lalevee and Duygu Avci}, doi = {10.1016/j.porgcoat.2018.12.014}, year = {2019}, date = {2019-03-01}, journal = {Progress in Organic Coatings}, volume = {128}, pages = {148--156}, abstract = {The synthesis of the first photoinitiator (PI) based on thioxanthone (TX) with 1,6-heptadiene structure is described. This PI (TXdMA) absorbs in the near UV-vis region (435-439 rim; with absorption redshift approximate to 50 nm and e values comparable to TX). Photopolymerization results demonstrate that although TXdMA is not an effective one-component polymerizable photoinitiator, it can successfully initiate photopolymerization of poly(ethylene glycol) diacrylate (PEGDA}, keywords = {}, pubstate = {published}, tppubtype = {article} } The synthesis of the first photoinitiator (PI) based on thioxanthone (TX) with 1,6-heptadiene structure is described. This PI (TXdMA) absorbs in the near UV-vis region (435-439 rim; with absorption redshift approximate to 50 nm and e values comparable to TX). Photopolymerization results demonstrate that although TXdMA is not an effective one-component polymerizable photoinitiator, it can successfully initiate photopolymerization of poly(ethylene glycol) diacrylate (PEGDA |
Ay, Emel; Gerard, Violaine; Graff, Bernadette; Morlet-Savary, Fabrice; Mutilangi, William; Galopin, Christophe; Lalevee, Jacques Citral Photodegradation in Solution: Highlighting of a Radical Pathway in Parallel to Cyclization Pathway. (Article de journal) Journal of agricultural and food chemistry, 2019. @article{Ay2019, title = {Citral Photodegradation in Solution: Highlighting of a Radical Pathway in Parallel to Cyclization Pathway.}, author = { Emel Ay and Violaine Gerard and Bernadette Graff and Fabrice Morlet-Savary and William Mutilangi and Christophe Galopin and Jacques Lalevee}, doi = {10.1021/acs.jafc.8b07034}, year = {2019}, date = {2019-03-01}, journal = {Journal of agricultural and food chemistry}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Vauthier, Madeline; Jierry, Loic; Oliveira, Jamerson Carneiro; Hassouna, Lilia; Roucoules, Vincent; Gall, Florence Bally-Le Interfacial Thermoreversible Chemistry on Functional Coatings: A Focus on the Diels-Alder Reaction (Article de journal) Advanced Functional Materials, 29 (10), p. 1806765, 2019. @article{Vauthier2019a, title = {Interfacial Thermoreversible Chemistry on Functional Coatings: A Focus on the Diels-Alder Reaction}, author = { Madeline Vauthier and Loic Jierry and Jamerson Carneiro Oliveira and Lilia Hassouna and Vincent Roucoules and Florence Bally-Le Gall}, doi = {10.1002/adfm.201806765}, year = {2019}, date = {2019-03-01}, journal = {Advanced Functional Materials}, volume = {29}, number = {10}, pages = {1806765}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Guillevic, Mazheva; Pichot, Vincent; Fioux, Philippe; Schnell, Fabien; Spitzer, Denis Nanodiamond-based energetic core-shell composites: The route towards safer materials (Article de journal) Diamond and Related Materials, 93 , p. 150–158, 2019. @article{Guillevic2019, title = {Nanodiamond-based energetic core-shell composites: The route towards safer materials}, author = { Mazheva Guillevic and Vincent Pichot and Philippe Fioux and Fabien Schnell and Denis Spitzer}, doi = {10.1016/j.diamond.2019.02.006}, year = {2019}, date = {2019-03-01}, journal = {Diamond and Related Materials}, volume = {93}, pages = {150--158}, abstract = {This work proposes to determine how diamond has an influence on the structure (core-shell morphology or not) as well as on the desensitization of ND-RDX (Nanodiamond - cyclotrimethylenetrinitramine) mixtures. RDX is one of the most used high performance explosives worldwide for military and civil applications. ND-RDX composite core-shell particles are obtained by Spray Flash Evaporation (SFE), a patented process developed in the laboratory. The characteristics and pyrotechnical properties of the resulting core-shell compounds are then compared to those of composite materials prepared by other means like slow evaporation and physical mixing. Further investigation of the sample morphology and the core-shell architecture are also discussed in the light of XPS and BET measurements. Finally, the interest of the nanodiamond properties to elaborate an energetic material that combines high energetic performance with desensitization to impact and friction in order to ensure safer handling is outlined hereinafter.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This work proposes to determine how diamond has an influence on the structure (core-shell morphology or not) as well as on the desensitization of ND-RDX (Nanodiamond - cyclotrimethylenetrinitramine) mixtures. RDX is one of the most used high performance explosives worldwide for military and civil applications. ND-RDX composite core-shell particles are obtained by Spray Flash Evaporation (SFE), a patented process developed in the laboratory. The characteristics and pyrotechnical properties of the resulting core-shell compounds are then compared to those of composite materials prepared by other means like slow evaporation and physical mixing. Further investigation of the sample morphology and the core-shell architecture are also discussed in the light of XPS and BET measurements. Finally, the interest of the nanodiamond properties to elaborate an energetic material that combines high energetic performance with desensitization to impact and friction in order to ensure safer handling is outlined hereinafter. |
Chemtob, Abraham; Feillee, Noemi; Vaulot, Cyril; Ley, Christian; Nouen, Didier Le Self-Photopolymerization of Poly(disulfide) Oligomers (Article de journal) Acs Omega, 4 (3), p. 5722–5730, 2019. @article{Chemtob2019, title = {Self-Photopolymerization of Poly(disulfide) Oligomers}, author = { Abraham Chemtob and Noemi Feillee and Cyril Vaulot and Christian Ley and Didier Le Nouen}, doi = {10.1021/acsomega.9b00021}, year = {2019}, date = {2019-03-01}, journal = {Acs Omega}, volume = {4}, number = {3}, pages = {5722--5730}, abstract = {Base catalyst and oxidant are usually necessary to promote the polymerization of poly(disulfide) oligomers through oxidative coupling of the terminal SH groups into S-S bonds. In this study, we prove that self-polymerization of bifunctional (disulfide) oligomer films can take place in a matter of minutes under UVC irradiation (254 nm, 10.5 mW cm(-2)). The resulting insoluble polymer is characterized using solid-state NMR, H-1 T-2 NMR relaxation measurements, thermal analysis, and Fourier-transform infrared spectroscopy and proves to have similar composition as a model poly(disulfide) prepared under oxidative conditions, but distinct physical properties. These differences are explained by a change in polymer architecture due to a higher ratio of cyclization relative to linear polymerization. Homolytic photocleavage of internal S-S bonds creates thiyl groups close to each other, driving an increased kinetic feasibility for the cyclization reaction by radical coupling. The subsequent formation of mechanically interlocked macrocycles (polycatenane network) is proposed to account for film properties analogous to those of a cross-linked polymer.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Base catalyst and oxidant are usually necessary to promote the polymerization of poly(disulfide) oligomers through oxidative coupling of the terminal SH groups into S-S bonds. In this study, we prove that self-polymerization of bifunctional (disulfide) oligomer films can take place in a matter of minutes under UVC irradiation (254 nm, 10.5 mW cm(-2)). The resulting insoluble polymer is characterized using solid-state NMR, H-1 T-2 NMR relaxation measurements, thermal analysis, and Fourier-transform infrared spectroscopy and proves to have similar composition as a model poly(disulfide) prepared under oxidative conditions, but distinct physical properties. These differences are explained by a change in polymer architecture due to a higher ratio of cyclization relative to linear polymerization. Homolytic photocleavage of internal S-S bonds creates thiyl groups close to each other, driving an increased kinetic feasibility for the cyclization reaction by radical coupling. The subsequent formation of mechanically interlocked macrocycles (polycatenane network) is proposed to account for film properties analogous to those of a cross-linked polymer. |
Tsangas, Michail; Jeguirim, Mejdi; Limousy, Lionel; Zorpas, Antonis The Application of Analytical Hierarchy Process in Combination with PESTEL-SWOT Analysis to Assess the Hydrocarbons Sector in Cyprus (Article de journal) Energies, 12 (5), p. 791, 2019. @article{Tsangas2019, title = {The Application of Analytical Hierarchy Process in Combination with PESTEL-SWOT Analysis to Assess the Hydrocarbons Sector in Cyprus}, author = { Michail Tsangas and Mejdi Jeguirim and Lionel Limousy and Antonis Zorpas}, doi = {10.3390/en12050791}, year = {2019}, date = {2019-03-01}, journal = {Energies}, volume = {12}, number = {5}, pages = {791}, abstract = {Natural gas reserves have been recently found offshore of Cyprus. Hence, a new energy sector is under development, creating potential for raised welfare for the small insular EU member. Several social and economic benefits could be achieved from the resources' exploitation. However, natural gas is a non-renewable energy source, connected with the major environmental issues of fossil fuels. The research goal of this work was to evaluate the sustainability of the new hydrocarbons sector. This was attained using a set of indicators, developed from the combination of PESTEL (Political, Economic, Technical, Social, Environmental, Legal) and SWOT (Strengths, Weaknesses, Opportunities, Threats) analyses. These were quantified using the Analytical Hierarchy Process (AHP) weighting method. They were pairwise compared and evaluated, resulting to a size for each one. The judgements of four evaluators, representing diverse interested parties, were used. The strengths and opportunities of the sector were found to be more than the weaknesses and threats. The relevant indicators quantification demonstrates also that the value of the positives is higher than the negatives. Therefore, if the first are enhanced and the latter are mitigated, there is sustainability potential. The sectors environmental issues are evaluated as the most important, followed by the economic. The other takes lower but comparatively significant values, and must be handled accordingly. These results lead to useful conclusions and could be exploited for decision-making and policies formulation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Natural gas reserves have been recently found offshore of Cyprus. Hence, a new energy sector is under development, creating potential for raised welfare for the small insular EU member. Several social and economic benefits could be achieved from the resources' exploitation. However, natural gas is a non-renewable energy source, connected with the major environmental issues of fossil fuels. The research goal of this work was to evaluate the sustainability of the new hydrocarbons sector. This was attained using a set of indicators, developed from the combination of PESTEL (Political, Economic, Technical, Social, Environmental, Legal) and SWOT (Strengths, Weaknesses, Opportunities, Threats) analyses. These were quantified using the Analytical Hierarchy Process (AHP) weighting method. They were pairwise compared and evaluated, resulting to a size for each one. The judgements of four evaluators, representing diverse interested parties, were used. The strengths and opportunities of the sector were found to be more than the weaknesses and threats. The relevant indicators quantification demonstrates also that the value of the positives is higher than the negatives. Therefore, if the first are enhanced and the latter are mitigated, there is sustainability potential. The sectors environmental issues are evaluated as the most important, followed by the economic. The other takes lower but comparatively significant values, and must be handled accordingly. These results lead to useful conclusions and could be exploited for decision-making and policies formulation. |
Khiari, Besma; Moussaoui, Marwa; Jeguirim, Mejdi Tomato-Processing By-Product Combustion: Thermal and Kinetic Analyses. (Article de journal) Materials (Basel, Switzerland), 12 (4), 2019. @article{Khiari2019a, title = {Tomato-Processing By-Product Combustion: Thermal and Kinetic Analyses.}, author = { Besma Khiari and Marwa Moussaoui and Mejdi Jeguirim}, doi = {10.3390/ma12040553}, year = {2019}, date = {2019-02-01}, journal = {Materials (Basel, Switzerland)}, volume = {12}, number = {4}, abstract = {This paper is part of a sustainable development approach, the aim being to develop a thermochemical energy recovery path while reducing the amount of tomato waste issued from agro-industrial units. The thermal process may contribute to an environmentally friendly management and help tomato processing industries creating new economic profitable circuits in an increasingly competitive context. The adopted approach was to follow the operating conditions needed for a complete thermal degradation through a thermal and kinetic analyses. The results of the tomato waste characterization confirmed their suitability to a thermochemical processing with high volatiles and fixed carbon and interesting high heating values comparable to sawdust biomass. We were able to isolate of the decomposition domains and extract kinetic parameters. Three kinetic models were applied; Flynn⁻Wall⁻Ozawa (FWO) simulated the best the combustion process. Calculated curves were validated by the first order (n = 1) model except for the slow heating rate of 5 °C/min which was fitted by the contracted cylinder model. The conclusions of this paper could help in optimizing the combustion process in order to achieve high energy recovery from tomato residues. Obtained kinetic data would help in the design of combustion reactors.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper is part of a sustainable development approach, the aim being to develop a thermochemical energy recovery path while reducing the amount of tomato waste issued from agro-industrial units. The thermal process may contribute to an environmentally friendly management and help tomato processing industries creating new economic profitable circuits in an increasingly competitive context. The adopted approach was to follow the operating conditions needed for a complete thermal degradation through a thermal and kinetic analyses. The results of the tomato waste characterization confirmed their suitability to a thermochemical processing with high volatiles and fixed carbon and interesting high heating values comparable to sawdust biomass. We were able to isolate of the decomposition domains and extract kinetic parameters. Three kinetic models were applied; Flynn⁻Wall⁻Ozawa (FWO) simulated the best the combustion process. Calculated curves were validated by the first order (n = 1) model except for the slow heating rate of 5 °C/min which was fitted by the contracted cylinder model. The conclusions of this paper could help in optimizing the combustion process in order to achieve high energy recovery from tomato residues. Obtained kinetic data would help in the design of combustion reactors. |
Mortada, Boushra; Chaplais, Gerald; Nouali, Habiba; Marichal, Claire; Patarin, Joel Phase Transformations of Metal-Organic Frameworks MAF-6 and ZIF-71 during Intrusion-Extrusion Experiments (Article de journal) Journal of Physical Chemistry C, 123 (7), p. 4319–4328, 2019. @article{Mortada2019, title = {Phase Transformations of Metal-Organic Frameworks MAF-6 and ZIF-71 during Intrusion-Extrusion Experiments}, author = { Boushra Mortada and Gerald Chaplais and Habiba Nouali and Claire Marichal and Joel Patarin}, doi = {10.1021/acs.jpcc.8b12047}, year = {2019}, date = {2019-02-01}, journal = {Journal of Physical Chemistry C}, volume = {123}, number = {7}, pages = {4319--4328}, abstract = {In this work, the energetic behaviors of two zeolitic imidazolate framework (ZIF) materials, ZIF-71 and the highly porous MAF-6, of RHO topology are studied in high-pressure intrusion-extrusion experiments using LiCl 20 M aqueous solution and/or water as nonwetting liquids. During the intrusion-extrusion experiments, both MAF-6 and ZIF-71 structures undergo phase transformations under the combined effects of high pressure and the nonwetting liquid. For the "MAF-6 H2O" system, the volume variation step observed on the intrusion curve of the first intrusion-extrusion cycle partially corresponds to the intrusion of water molecules inside the MAF-6 pores associated with a partial and irreversible phase transformation of MAF-6 into a nonporous and unidentified phase X. When the pressure is released, that is, when the experiment is stopped at the end of the volume variation step and the system returns to atmospheric pressure, the intruded water molecules are expelled from the porosity of the remaining MAF-6 material, and the "MAF-6-H2O" system, therefore, displays a mixture of shock-absorber and bumper behaviors. In the case of both "MAF-6" and "ZIF-71-LiCl 20 M aqueous solution" systems, the volume variation step is shifted to a higher pressure range, indicating that the intrusion of the nonwetting liquid molecules occurs at a higher pressure because of the presence of electrolytes. For the "MAF-6 LiCl 20 M aqueous solution" system, a mixture of MAF-6 and phase X is obtained at the end of the volume variation step, which probably indicates energetic behavior similar to the one observed for the "MAF-6 H2O" system (i.e., a mixture of shock-absorber and bumper behaviors). In the case of the "ZIF-71-LiCl 20 M aqueous solution" system, the volume variation step observed on the intrusion curve of the first intrusion-extrusion cycle corresponds to a phase transformation. At the end of this step, the ZIF-71 structure is completely transformed into ZIF-72 (lcs). The "ZIF-71 LiCl 20 M aqueous solution" system, thus, displays bumper behavior, as the supplied mechanical energy is absorbed during the irreversible phase transformation phenomenon.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this work, the energetic behaviors of two zeolitic imidazolate framework (ZIF) materials, ZIF-71 and the highly porous MAF-6, of RHO topology are studied in high-pressure intrusion-extrusion experiments using LiCl 20 M aqueous solution and/or water as nonwetting liquids. During the intrusion-extrusion experiments, both MAF-6 and ZIF-71 structures undergo phase transformations under the combined effects of high pressure and the nonwetting liquid. For the "MAF-6 H2O" system, the volume variation step observed on the intrusion curve of the first intrusion-extrusion cycle partially corresponds to the intrusion of water molecules inside the MAF-6 pores associated with a partial and irreversible phase transformation of MAF-6 into a nonporous and unidentified phase X. When the pressure is released, that is, when the experiment is stopped at the end of the volume variation step and the system returns to atmospheric pressure, the intruded water molecules are expelled from the porosity of the remaining MAF-6 material, and the "MAF-6-H2O" system, therefore, displays a mixture of shock-absorber and bumper behaviors. In the case of both "MAF-6" and "ZIF-71-LiCl 20 M aqueous solution" systems, the volume variation step is shifted to a higher pressure range, indicating that the intrusion of the nonwetting liquid molecules occurs at a higher pressure because of the presence of electrolytes. For the "MAF-6 LiCl 20 M aqueous solution" system, a mixture of MAF-6 and phase X is obtained at the end of the volume variation step, which probably indicates energetic behavior similar to the one observed for the "MAF-6 H2O" system (i.e., a mixture of shock-absorber and bumper behaviors). In the case of the "ZIF-71-LiCl 20 M aqueous solution" system, the volume variation step observed on the intrusion curve of the first intrusion-extrusion cycle corresponds to a phase transformation. At the end of this step, the ZIF-71 structure is completely transformed into ZIF-72 (lcs). The "ZIF-71 LiCl 20 M aqueous solution" system, thus, displays bumper behavior, as the supplied mechanical energy is absorbed during the irreversible phase transformation phenomenon. |
Jeguirim, Mejdi; Limousy, Lionel Biomass Chars: Elaboration, Characterization and Applications II (Article de journal) Energies, 12 (3), p. 384, 2019. @article{Jeguirim2019, title = {Biomass Chars: Elaboration, Characterization and Applications II}, author = { Mejdi Jeguirim and Lionel Limousy}, doi = {10.3390/en12030384}, year = {2019}, date = {2019-02-01}, journal = {Energies}, volume = {12}, number = {3}, pages = {384}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Abidi, Nejib; Duplay, Joelle; Jada, Amane; Errais, Emna; Ghazi, Malika; Semhi, Khadija; Trabelsi-Ayadi, Malika Removal of anionic dye from textile industries' effluents by using Tunisian clays as adsorbents. Zeta potential and streaming-induced potential measurements (Article de journal) Comptes Rendus Chimie, 22 (2-3), p. Latvian Clay Sci Soc, 2019. @article{Abidi2019, title = {Removal of anionic dye from textile industries' effluents by using Tunisian clays as adsorbents. Zeta potential and streaming-induced potential measurements}, author = { Nejib Abidi and Joelle Duplay and Amane Jada and Emna Errais and Malika Ghazi and Khadija Semhi and Malika Trabelsi-Ayadi}, doi = {10.1016/j.crci.2018.10.006}, year = {2019}, date = {2019-02-01}, journal = {Comptes Rendus Chimie}, volume = {22}, number = {2-3}, pages = {Latvian Clay Sci Soc}, abstract = {In the present work, we have investigated the adsorption capacities of natural raw clays originated from Tunisia, such as those from Tabarka (a mixture of kaolinite and illite) and from Fouchana (a mixture of smectite, kaolinite, and illite), a standard kaolinite (KGa-2), and a palygorskite (PFI-1) for the removal of a reactive red dye (RR 120) usually found in textile industry effluents. Thus, batch adsorption experiments were performed and were tuned by varying different parameters such as adsorption contact time, aqueous phase pH, ionic strength, and initial dye concentration. In addition, zeta potential measurements allowed the determination of the electrical charge and of the dye behavior at the clay -water interface. Despite the fact that palygorskite has higher porosity and specific surface values, the amount of dye adsorbed on this clay is low in comparison to that of the other solid samples, regardless of the values of pH and ionic strength of the aqueous phase. On the other hand, a higher amount of adsorbed dye was observed on KGa-2, having the lowest specific surface area value. This sample, in comparison to smectite and fibrous clays, was found to be more efficient in the removal the anionic dye, and thus it can be used as an adsorbent for the treatment of effluents in the textile industry. (C) 2018 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In the present work, we have investigated the adsorption capacities of natural raw clays originated from Tunisia, such as those from Tabarka (a mixture of kaolinite and illite) and from Fouchana (a mixture of smectite, kaolinite, and illite), a standard kaolinite (KGa-2), and a palygorskite (PFI-1) for the removal of a reactive red dye (RR 120) usually found in textile industry effluents. Thus, batch adsorption experiments were performed and were tuned by varying different parameters such as adsorption contact time, aqueous phase pH, ionic strength, and initial dye concentration. In addition, zeta potential measurements allowed the determination of the electrical charge and of the dye behavior at the clay -water interface. Despite the fact that palygorskite has higher porosity and specific surface values, the amount of dye adsorbed on this clay is low in comparison to that of the other solid samples, regardless of the values of pH and ionic strength of the aqueous phase. On the other hand, a higher amount of adsorbed dye was observed on KGa-2, having the lowest specific surface area value. This sample, in comparison to smectite and fibrous clays, was found to be more efficient in the removal the anionic dye, and thus it can be used as an adsorbent for the treatment of effluents in the textile industry. (C) 2018 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved. |
Issaoui, Mansour; Limousy, Lionel Low-cost ceramic membranes: Synthesis, classifications, and applications (Article de journal) Comptes Rendus Chimie, 22 (2-3), p. Latvian Clay Sci Soc, 2019. @article{Issaoui2019, title = {Low-cost ceramic membranes: Synthesis, classifications, and applications}, author = { Mansour Issaoui and Lionel Limousy}, doi = {10.1016/j.crci.2018.09.014}, year = {2019}, date = {2019-02-01}, journal = {Comptes Rendus Chimie}, volume = {22}, number = {2-3}, pages = {Latvian Clay Sci Soc}, abstract = {The elaboration of porous ceramic membranes using low cost materials has attracted much interest. Indeed, the choice of suitable raw materials (including additives or binders) is critical to the membrane's performance. However, with the growing need for more cost-effective resources with superior performance, many studies have been conducted for selecting suitable cheap raw materials for the intended use and then adjusting the overall characteristics, and therefore allowing the ceramic membranes to be tailored to suit a wide range of industrial applications. Many attempts have been made by researchers to produce porous ceramic membranes from specific materials, but their industrial applications remain very limited because of the high cost of the raw materials used. The use of ceramic materials for producing membranes has many advantages, such as high mechanical and chemical stability and excellent thermal resistivity. The evaluation of membrane performances, essentially their permeability and rejection, can assert their use in many industrial fields, namely beverage and food, pharmaceutical, biotechnology, petrochemical industries as well as water treatment and several other environmental problems. This article aims to make a thorough review of the different processes used in the synthesis of ceramic membranes using inexpensive raw materials as well as their intrinsic characteristics and industrial applications in several sensitive fields taking into account both economic and environmental aspects. (C) 2018 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The elaboration of porous ceramic membranes using low cost materials has attracted much interest. Indeed, the choice of suitable raw materials (including additives or binders) is critical to the membrane's performance. However, with the growing need for more cost-effective resources with superior performance, many studies have been conducted for selecting suitable cheap raw materials for the intended use and then adjusting the overall characteristics, and therefore allowing the ceramic membranes to be tailored to suit a wide range of industrial applications. Many attempts have been made by researchers to produce porous ceramic membranes from specific materials, but their industrial applications remain very limited because of the high cost of the raw materials used. The use of ceramic materials for producing membranes has many advantages, such as high mechanical and chemical stability and excellent thermal resistivity. The evaluation of membrane performances, essentially their permeability and rejection, can assert their use in many industrial fields, namely beverage and food, pharmaceutical, biotechnology, petrochemical industries as well as water treatment and several other environmental problems. This article aims to make a thorough review of the different processes used in the synthesis of ceramic membranes using inexpensive raw materials as well as their intrinsic characteristics and industrial applications in several sensitive fields taking into account both economic and environmental aspects. (C) 2018 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved. |
Miron, Simona M; Dutournie, Patrick; Thabet, Kawther; Ponche, Arnaud Filtration of protein-based solutions with ceramic ultrafiltration membrane. Study of selectivity, adsorption, and protein denaturation (Article de journal) Comptes Rendus Chimie, 22 (2-3), p. Latvian Clay Sci Soc, 2019. @article{Miron2019, title = {Filtration of protein-based solutions with ceramic ultrafiltration membrane. Study of selectivity, adsorption, and protein denaturation}, author = { Simona M. Miron and Patrick Dutournie and Kawther Thabet and Arnaud Ponche}, doi = {10.1016/j.crci.2018.09.011}, year = {2019}, date = {2019-02-01}, journal = {Comptes Rendus Chimie}, volume = {22}, number = {2-3}, pages = {Latvian Clay Sci Soc}, abstract = {Proteins are widely used in food or pharmaceutical industry and are often pumped in complex flow systems. Their biological activity is intrinsically related to their conformation in solution. In this work, we studied the state and behavior of proteins in solution during separation/concentration operation in terms of adsorption, molecule agglomeration, and denaturation. Solutions of lysozyme have been filtrated on a ceramic ultrafiltration membrane at high flow velocity and different transmembrane pressures to investigate the effect of flow parameters on the protein conformation in solution assessed by size-exclusion chromatography. A shift of 0.4 min in elution time of the peak corresponding to lysozyme is observed between retentate and permeate solutions, indicating that the lysozyme molecules exhibit drastic conformation changes after filtration. In addition, the effect of the filtrated solute nature on the pore surface (adsorption phenomena) is investigated by following the evolution of the hydraulic and selectivity membrane performances. (C) 2018 Published by Elsevier Masson SAS on behalf of Academie des sciences.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Proteins are widely used in food or pharmaceutical industry and are often pumped in complex flow systems. Their biological activity is intrinsically related to their conformation in solution. In this work, we studied the state and behavior of proteins in solution during separation/concentration operation in terms of adsorption, molecule agglomeration, and denaturation. Solutions of lysozyme have been filtrated on a ceramic ultrafiltration membrane at high flow velocity and different transmembrane pressures to investigate the effect of flow parameters on the protein conformation in solution assessed by size-exclusion chromatography. A shift of 0.4 min in elution time of the peak corresponding to lysozyme is observed between retentate and permeate solutions, indicating that the lysozyme molecules exhibit drastic conformation changes after filtration. In addition, the effect of the filtrated solute nature on the pore surface (adsorption phenomena) is investigated by following the evolution of the hydraulic and selectivity membrane performances. (C) 2018 Published by Elsevier Masson SAS on behalf of Academie des sciences. |
Frikha, Kawthar; Limousy, Lionel; Bouaziz, Jamel; Bennici, Simona; Chaari, Kamel; Jeguirim, Mejdi Elaboration of alumina-based materials by solution combustion synthesis: A review (Article de journal) Comptes Rendus Chimie, 22 (2-3), p. Latvian Clay Sci Soc, 2019. @article{Frikha2019b, title = {Elaboration of alumina-based materials by solution combustion synthesis: A review}, author = { Kawthar Frikha and Lionel Limousy and Jamel Bouaziz and Simona Bennici and Kamel Chaari and Mejdi Jeguirim}, doi = {10.1016/j.crci.2018.10.004}, year = {2019}, date = {2019-02-01}, journal = {Comptes Rendus Chimie}, volume = {22}, number = {2-3}, pages = {Latvian Clay Sci Soc}, abstract = {Alumina (Al2O3) is by far the most commonly used material in industry. It is applied in microelectronics, refractory, catalytic processing, coatings, energy storage, environment protection, and in a wide variety of other industrial applications. In the past decades, various methods have been adopted to synthesize alumina with different properties. Among these methods, solution combustion is considered as an efficient and economic synthesis route, because of its simplicity, low energy consumption, short processing time, and low processing cost. Recent innovations in the combustion and processing parameters have allowed applying this method for the development of a wide range of alumina-based materials. In this review, an overview of the synthesis of alumina and related materials by solution combustion method was provided, relying on the research works reported in the literature since 1988. (C) 2018 Academie des sciences. Published by Elsevier Masson SAS.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Alumina (Al2O3) is by far the most commonly used material in industry. It is applied in microelectronics, refractory, catalytic processing, coatings, energy storage, environment protection, and in a wide variety of other industrial applications. In the past decades, various methods have been adopted to synthesize alumina with different properties. Among these methods, solution combustion is considered as an efficient and economic synthesis route, because of its simplicity, low energy consumption, short processing time, and low processing cost. Recent innovations in the combustion and processing parameters have allowed applying this method for the development of a wide range of alumina-based materials. In this review, an overview of the synthesis of alumina and related materials by solution combustion method was provided, relying on the research works reported in the literature since 1988. (C) 2018 Academie des sciences. Published by Elsevier Masson SAS. |
Allam, Djaouida; Bennici, Simona; Limousy, Lionel; Hocine, Smain Improved Cu- and Zn-based catalysts for CO2 hydrogenation to methanol (Article de journal) Comptes Rendus Chimie, 22 (2-3), p. Latvian Clay Sci Soc, 2019. @article{Allam2019, title = {Improved Cu- and Zn-based catalysts for CO2 hydrogenation to methanol}, author = { Djaouida Allam and Simona Bennici and Lionel Limousy and Smain Hocine}, doi = {10.1016/j.crci.2019.01.002}, year = {2019}, date = {2019-02-01}, journal = {Comptes Rendus Chimie}, volume = {22}, number = {2-3}, pages = {Latvian Clay Sci Soc}, abstract = {In this study the influence of metal dispersion, spinel formation, and surface properties of binary and ternary catalysts (CuO-CeO2, ZnO-CeO2, CuO-ZnO-CeO2, and CuO-ZnO-Al2O3) was evaluated. The catalysts prepared by polyol method using polyethylene glycol as a solvent have been tested in the CO2 hydrogenation to methanol performed at atmospheric pressure. The catalysts prepared by polyol method presented improved properties in terms of metal oxide dispersion, morphology (i.e. sponge-like shape for the CeO2-containing catalysts), and a large variety of metal and metal oxide species on the surface. Moreover, the CuO-ZnO-CeO2 and CuO-ZnO-Al2O3 catalysts exhibited a higher activity and selectivity in the methanol synthesis by CO2 hydrogenation than those displayed by catalysts prepared by more conventional methods. (C) 2019 Academie des sciences. Published by Elsevier Masson SAS.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this study the influence of metal dispersion, spinel formation, and surface properties of binary and ternary catalysts (CuO-CeO2, ZnO-CeO2, CuO-ZnO-CeO2, and CuO-ZnO-Al2O3) was evaluated. The catalysts prepared by polyol method using polyethylene glycol as a solvent have been tested in the CO2 hydrogenation to methanol performed at atmospheric pressure. The catalysts prepared by polyol method presented improved properties in terms of metal oxide dispersion, morphology (i.e. sponge-like shape for the CeO2-containing catalysts), and a large variety of metal and metal oxide species on the surface. Moreover, the CuO-ZnO-CeO2 and CuO-ZnO-Al2O3 catalysts exhibited a higher activity and selectivity in the methanol synthesis by CO2 hydrogenation than those displayed by catalysts prepared by more conventional methods. (C) 2019 Academie des sciences. Published by Elsevier Masson SAS. |
Miron, Simona M; Brendle, Jocelyne; Josien, Ludovic; Fourcade, Florence; Rojas, Franck; Amrane, Abdeltif; Limousy, Lionel Development of a new cathode for the electro-Fenton process combining carbon felt and iron-containing organic-inorganic hybrids (Article de journal) Comptes Rendus Chimie, 22 (2-3), p. Latvian Clay Sci Soc, 2019. @article{Miron2019a, title = {Development of a new cathode for the electro-Fenton process combining carbon felt and iron-containing organic-inorganic hybrids}, author = { Simona M. Miron and Jocelyne Brendle and Ludovic Josien and Florence Fourcade and Franck Rojas and Abdeltif Amrane and Lionel Limousy}, doi = {10.1016/j.crci.2018.11.012}, year = {2019}, date = {2019-02-01}, journal = {Comptes Rendus Chimie}, volume = {22}, number = {2-3}, pages = {Latvian Clay Sci Soc}, abstract = {New kinds of electrodes were prepared for implementation in the electro-Fenton process. Based on carbon felt/organic-inorganic talc like hybrid (TLH), the electrodes were successfully prepared by a simple one-step sol-gel procedure at room temperature, from aminopropyltrimethoxysilane, magnesium and iron(III) hexahydrated chlorides, carbon felt, and ethanol. They were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray fluorescence, thermal analysis, scanning electron microscopy, and solid-state nuclear magnetic resonance. It was shown that the order of carbon felt addition to the prepared solution is a key point to form a thin and homogeneous TLH layer at the surface of the carbon fibers. Also, composites having different Fe/Mg molar ratios can be obtained. The composite containing 100 wt % Fe was successfully tested as an electrode for the electro-Fenton process, because 98% degradation yield was obtained after 4 h of electrolysis. These results show that Fenton's reaction can be achieved with immobilized iron and H2O2 produced at the cathode, which can account for the better degradation yield as compared with 70.5% obtained during electrolysis with a nonmodified cathode under the same operating conditions. Consequently, the use of such a material as an electrode for the electro-Fenton process was proven to merit further studies and, notably, to be used for the processing of industrial pharmaceutical effluents. (C) 2019 Academie des sciences. Published by Elsevier Masson SAS.}, keywords = {}, pubstate = {published}, tppubtype = {article} } New kinds of electrodes were prepared for implementation in the electro-Fenton process. Based on carbon felt/organic-inorganic talc like hybrid (TLH), the electrodes were successfully prepared by a simple one-step sol-gel procedure at room temperature, from aminopropyltrimethoxysilane, magnesium and iron(III) hexahydrated chlorides, carbon felt, and ethanol. They were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray fluorescence, thermal analysis, scanning electron microscopy, and solid-state nuclear magnetic resonance. It was shown that the order of carbon felt addition to the prepared solution is a key point to form a thin and homogeneous TLH layer at the surface of the carbon fibers. Also, composites having different Fe/Mg molar ratios can be obtained. The composite containing 100 wt % Fe was successfully tested as an electrode for the electro-Fenton process, because 98% degradation yield was obtained after 4 h of electrolysis. These results show that Fenton's reaction can be achieved with immobilized iron and H2O2 produced at the cathode, which can account for the better degradation yield as compared with 70.5% obtained during electrolysis with a nonmodified cathode under the same operating conditions. Consequently, the use of such a material as an electrode for the electro-Fenton process was proven to merit further studies and, notably, to be used for the processing of industrial pharmaceutical effluents. (C) 2019 Academie des sciences. Published by Elsevier Masson SAS. |
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Réseaux sociaux
IS2M
Bâtiment CNRS
15, rue Jean Starcky - BP 2488
68057 Mulhouse cedex
Bâtiment IRJBD
3 bis, rue Alfred Werner
68093 Mulhouse cedex
tel: (+33)3 89 60 87 00
fax: (+33)3 89 60 87 99
Réseaux sociaux
IS2M
Bâtiment CNRS
15, rue Jean Starcky - BP 2488
68057 Mulhouse cedex
Bâtiment IRJBD
3 bis, rue Alfred Werner
68093 Mulhouse cedex
tel: (+33)3 89 60 87 00
fax: (+33)3 89 60 87 99
Réseaux sociaux
Plan
- L’institut
- Recherche
- Les axes thématiques
- Ingénierie des Polymères Fonctionnels
- Matériaux à Porosité Contrôlée
- Carbone et Matériaux Hybrides
- Molécules, Nano-, Micro-Structures : Elaboration et Fonctionnalités
- Transferts, Réactivité, Matériaux pour les procédés propres
- Physique des systèmes de basse dimensionnalité
- Biomatériaux-Biointerfaces
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- Les 11 plateformes de caractérisation
- Adsorption
- Diffusion et Diffraction des Rayons X (DRX)
- Analyses Mécaniques, Thermomécaniques et Rhéologiques (AMTR)
- AFM ou Microscopie à champ proche
- Microscopie confocale
- Microscopies électroniques
- Microscopie numérique
- Mouillabilité
- RMN du solide
- Spectroscopie FTIR et Raman
- Spectroscopie de Photoélectrons X
- Projets
- Emplois
- Formations