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169 results on '"Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES)"'

1. Flame Retardancy of PA6 Using a Guanidine Sulfamate/Melamine Polyphosphate Mixture

Author

Sophie Duquesne, Mathilde Casetta, Serge Bourbigot, Jun Sun, Sheng Zhang, Xiaoyu Gu, Mathieu Coquelle, Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), University of Chinese Academy of Sciences [Beijing] (UCAS), Beijing University of Chemical Technology, Université de Lille, ENSCL, CNRS, INRA, Unité Matériaux et Transformations (UMET) - UMR 8207, Laboratoire de structures et propriétés de l'état solide [LSPES], Unité Matériaux et Transformations - UMR 8207 [UMET], Laboratoire de structures et propriétés de l'état solide - UMR 8008 [LSPES], and University of Chinese Academy of Sciences [Beijing] [UCAS]

Subjects
Polymers and Plastics, polyamide 6, Polyphosphate, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, guanidine sulfamate, Limiting oxygen index, [SPI.MAT]Engineering Sciences [physics]/Materials, lcsh:QD241-441, chemistry.chemical_compound, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Chemical engineering, lcsh:Organic chemistry, Polyamide, Organic chemistry, Degradation (geology), UL 94, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Melamine, Ammonium sulfamate, flame retardancy, Fire retardant
Abstract

Polyamide 6 (PA6) is a widely-used polymer that could find applications in various sectors, including home textiles, transportation or construction. However, due to its organic nature, PA6 is flammable, and flame-retardant formulations have to be developed to comply with fire safety standards. Recently, it was proposed to use ammonium sulfamate as an effective flame retardant for PA6, even at low loading content. However, processing issues could occur with this additive considering large-scale production. This paper thus studies the use of another sulfamate salt—guanidine sulfamate (GAS)—and evidences its high efficiency when combined with melamine polyphosphate (MPP) as a flame retardant for PA6. A decrease of the peak of the heat release rate by 30% compared to pure PA6 was obtained using only 5 wt% of a GAS/MPP mixture in a microscale calorimeter. Moreover, PA6 containing the mixture GAS/MPP exhibits a Limiting Oxygen Index (LOI) of 37 vol% and is rated V0 for the UL 94 test (Vertical Burning Test, ASTM D 3801). The mechanisms of degradation were investigated analyzing the gas phase and solid phase when the material degrades. It was proposed that MPP and GAS modify the degradation pathway of PA6, leading to the formation of nitrile end-group-containing molecules. Moreover, the formation of a polyaromatic structure by the reaction of MPP and PA6 was also shown.

Published
2015
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2. Characterization of thermo-physical properties of EVA/ATH: Application to gasification experiments and pyrolysis modeling

Author

Sophie Duquesne, Bertrand Girardin, Gaelle Fontaine, Michael Försth, Serge Bourbigot, Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Université de Lille, ENSCL, CNRS, INRA, Laboratoire de structures et propriétés de l'état solide [LSPES], Unité Matériaux et Transformations (UMET) - UMR 8207, Laboratoire de structures et propriétés de l'état solide - UMR 8008 [LSPES], and Unité Matériaux et Transformations - UMR 8207 [UMET]

Subjects
heat capacity, Phase transition, ethylene vinyl acetate copolymer, Materials science, gasification, Heat capacity, lcsh:Technology, Isothermal process, Article, aluminum tri-hydroxide, [SPI.MAT]Engineering Sciences [physics]/Materials, Differential scanning calorimetry, Thermal conductivity, General Materials Science, thermal conductivity, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Ceramic, Composite material, lcsh:Microscopy, lcsh:QC120-168.85, lcsh:QH201-278.5, lcsh:T, [CHIM.MATE]Chemical Sciences/Material chemistry, pyrolysis modelling, [CHIM.POLY]Chemical Sciences/Polymers, Chemical engineering, lcsh:TA1-2040, visual_art, Heat transfer, visual_art.visual_art_medium, lcsh:Descriptive and experimental mechanics, lcsh:Electrical engineering. Electronics. Nuclear engineering, lcsh:Engineering (General). Civil engineering (General), Pyrolysis, lcsh:TK1-9971
Abstract

International audience; The pyrolysis of solid polymeric materials is a complex process that involves both chemical and physical phenomena such as phase transitions, chemical reactions, heat transfer, and mass transport of gaseous components. For modeling purposes, it is important to characterize and to quantify the properties driving those phenomena, especially in the case of flame-retarded materials. In this study, protocols have been developed to characterize the thermal conductivity and the heat capacity of an ethylene-vinyl acetate copolymer (EVA) flame retarded with aluminum tri-hydroxide (ATH). These properties were measured for the various species identified across the decomposition of the material. Namely, the thermal conductivity was found to decrease as a function of temperature before decomposition whereas the ceramic residue obtained after the decomposition at the steady state exhibits a thermal conductivity as low as 0.2 W/m/K. The heat capacity of the material was also investigated using both isothermal modulated Differential Scanning Calorimetry (DSC) and the standard method (ASTM E1269). It was shown that the final residue exhibits a similar behavior to alumina, which is consistent with the decomposition pathway of EVA/ATH. Besides, the two experimental approaches give similar results over the whole range of temperatures. Moreover, the optical properties before decomposition and the heat capacity of the decomposition gases were also analyzed. Those properties were then used as input data for a pyrolysis model in order to predict gasification experiments. Mass losses of gasification experiments were well predicted, thus validating the characterization of the thermo-physical properties of the material

Published
2015
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3. The effects of thermophysical properties and environmental conditions on fire performance of intumescent coatings on glass fibre-reinforced epoxy composites

Author

Piyanuch Luangtriratana, Serge Bourbigot, Baljinder K. Kandola, Sophie Duquesne, Université de Lille, ENSCL, CNRS, INRA, Laboratoire de structures et propriétés de l'état solide [LSPES], Unité Matériaux et Transformations (UMET) - UMR 8207, University of Bolton, Laboratoire de structures et propriétés de l'état solide - UMR 8008 [LSPES], Unité Matériaux et Transformations - UMR 8207 [UMET], Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), and Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, intumescent coatings, char expansion, mechanical properties, lcsh:Technology, Article, [SPI.MAT]Engineering Sciences [physics]/Materials, Thermal barrier coating, Flexural strength, Cone calorimeter, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, General Materials Science, Composite material, lcsh:Microscopy, Flammability, lcsh:QC120-168.85, lcsh:QH201-278.5, lcsh:T, Delamination, cone calorimetry, [CHIM.MATE]Chemical Sciences/Material chemistry, Epoxy, Fire performance, thermal conductivity at high temperatures, [CHIM.POLY]Chemical Sciences/Polymers, lcsh:TA1-2040, visual_art, visual_art.visual_art_medium, durability, lcsh:Descriptive and experimental mechanics, lcsh:Electrical engineering. Electronics. Nuclear engineering, lcsh:Engineering (General). Civil engineering (General), lcsh:TK1-9971, Intumescent
Abstract

first_page settings Order Article Reprints Open AccessArticle The Effects of Thermophysical Properties and Environmental Conditions on Fire Performance of Intumescent Coatings on Glass Fibre-Reinforced Epoxy Composites by Baljinder K. Kandola 1,* [ORCID] , Piyanuch Luangtriratana 1 [ORCID] , Sophie Duquesne 2 and Serge Bourbigot 2 [ORCID] 1 Institute for Materials Research and Innovation, University of Bolton, Bolton BL3 5AB, UK 2 Unité Matériaux et Transformations (UMET)-CNRS UMR 8207-Group Reaction and Resistance to Fire (R2Fire), École Nationale Supérieure de Chimie de Lille, University of Lille, Avenue Mendeleiev, CS 90108, 59652 Villeneuve d'Ascq Cedex, France * Author to whom correspondence should be addressed. Materials 2015, 8(8), 5216-5237; https://doi.org/10.3390/ma8085216 Received: 29 May 2015 / Revised: 21 July 2015 / Accepted: 28 July 2015 / Published: 11 August 2015 (This article belongs to the Special Issue Influence of Thermo-Physical and Thermo-Optical Properties on the Fire Behavior of Polymers) Download Browse Figures Versions Notes Abstract Intumescent coatings are commonly used as passive fire protection systems for steel structures. The purpose of this work is to explore whether these can also be used effectively on glass fibre-reinforced epoxy (GRE) composites, considering the flammability of the composites compared to non-flammable steel substrate. The thermal barrier and reaction-to-fire properties of three commercial intumescent coatings on GRE composites have been studied using a cone calorimeter. Their thermophysical properties in terms of heating rate and/or temperature dependent char expansion ratios and thermal conductivities have been measured and correlated. It has been suggested that these two parameters can be used to design coatings to protect composite laminates of defined thicknesses for specified periods of time. The durability of the coatings to water absorption, peeling, impact, and flexural loading were also studied. A strong adhesion between all types of coatings and the substrate was observed. Water soaking had a little effect on the fire performance of epoxy based coatings. All types of 1 mm thick coatings on GRE helped in retaining ~90% of the flexural property after 2 min exposure to 50 kW/m2 heat flux whereas the uncoated laminate underwent severe delamination and loss in structural integrity after 1 min. 8;8

Published
2015
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4. Caractérisation locale de nanocomposites piézoélectriques par microscopie à force atomique

Author

Ferri, Anthony, Costa, Antonio Da, Barrau, Sophie, Defebvin, Juliette, Chambrier, Marie-Hélène, Marin, Adeline, Bourrez, Rudy, Leroy, Sébastien, Lefebvre, Jean-Marc, Desfeux, Rachel, Unité de Catalyse et de Chimie du Solide - Site Artois (UCCS Artois), Université d'Artois (UA)-Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et de Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Unité Matériaux et Transformations - UMR 8207 (UMET), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Laboratoire de structures et propriétés de l'état solide (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), UCCS Équipe Couches Minces & Nanomatériaux, Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille-Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and ANR-16-CE08-0025,NanoPiC,Etude du comportement piézoélectrique multi-échelles de composites innovants micro- et nano-structurés(2016)

Subjects
[CHIM.POLY]Chemical Sciences/Polymers, [CHIM]Chemical Sciences, [CHIM.MATE]Chemical Sciences/Material chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2019

5. Bottom-up fabrication of InAs-on-nothing MOSFET using selective area molecular beam epitaxy

Author

T.A. Karatsori, David Troadec, M Fahed, N. Wichmann, Xavier Wallart, Alexandre Bucamp, Gerard Ghibaudo, A. Olivier, Sylvain Bollaert, Ludovic Desplanque, Ahmed Addad, M. Pastorek, Y. Lechaux, Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Advanced NanOmeter DEvices - IEMN (ANODE - IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et Caractérisation (IMEP-LAHC ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), EPItaxie et PHYsique des hétérostructures - IEMN (EPIPHY - IEMN), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Centrale de Micro Nano Fabrication - IEMN (CMNF - IEMN), ANR-13-NANO-0001,MOSINAS,MOSFET à hétérostructure et film ultra mince d'InAs sur substrat silicium(2013), and Centrale de Micro Nano Fabrication - IEMN (CMNF-IEMN)

Subjects
Materials science, Fabrication, MBE, Bioengineering, Drain-induced barrier lowering, 02 engineering and technology, 010402 general chemistry, Epitaxy, 01 natural sciences, law.invention, MOSFET, law, InAs, Lattice (order), General Materials Science, Electrical and Electronic Engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Drain current, III-V, business.industry, Mechanical Engineering, Transistor, epitaxy, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Mechanics of Materials, Optoelectronics, 0210 nano-technology, business, Molecular beam epitaxy
Abstract

International audience; In this paper we report on the fabrication and electrical characterization of InAs-on-nothing metal-oxide-semiconductor field-effect transistor composed of a suspended InAs channel and raised InAs n+ contacts. This architecture is obtained using 3D selective and localized molecular beam epitaxy on a lattice mismatched InP substrate. The suspended InAs channel and InAs n+ contacts feature a reproducible and uniform shape with well-defined 3D sidewalls. Devices with 1 μm gate length present a saturation drain current (I Dsat) of 300 mA mm−1 at V DS = 0.8 V and a trans-conductance (GM ) of 120 mS mm−1 at V DS = 0.5 V. In terms of electrostatic control, the devices display a minimal subthreshold swing of 110 mV dec−1 at V DS = 0.5 V and a small drain induced barrier lowering of 50 mV V−1.

Published
2019
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6. Local-scale Modeling of Plasticity–Environment Interactions

Author

Yann Charles, Thierry Couvant, Gilbert Hénaff, Monique Gaspérini, Cecilie Duhamel, Arnaud Metsue, Nicolas Saintier, Matthieu Dhondt, Jamaa Bouhattate, Marion Frégonèse, Isabelle Aubert, Institut de Mécanique et d'Ingénierie de Bordeaux (I2M), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB)-École Nationale Supérieure d'Arts et Métiers (ENSAM), Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Université Paris 13 (UP13)-Institut Galilée-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS), EDF (EDF), Institut de Recherche Dupuy de Lôme (IRDL), Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Centre National de la Recherche Scientifique (CNRS), Centre des Matériaux (MAT), MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Matériaux, ingénierie et science [Villeurbanne] (MATEIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Mécanique et Physique des Matériaux (LMPM), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Sorbonne Paris Cité (USPC)-Institut Galilée-Université Paris 13 (UP13), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Brest (UBO)-Université de Bretagne Sud (UBS), MINES ParisTech - École nationale supérieure des mines de Paris-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Centre National de la Recherche Scientifique (CNRS)-ENSMA-Université de Poitiers, and Laboratoire de structures et propriétés de l'état solide (LSPES)

Subjects
010302 applied physics, Materials science, Initiation mechanisms modeling, Incubation modeling, Local scale, Incubation mechanism models, Interactions, Modeling, 02 engineering and technology, [PHYS.MECA]Physics [physics]/Mechanics [physics], Plasticity, [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph], 021001 nanoscience & nanotechnology, 01 natural sciences, Durability, Coupling (electronics), Plasticity–Environment, Simulate/predict degradation, Propagation mechanism models, Local-scale, 0103 physical sciences, Initiation modeling, 0210 nano-technology, Biological system, Propagation
Abstract

International audience; In the previous chapters we have presented the diversity and the complexity of the multiscale degradation mechanisms for mechanics-microstructure-environment coupling problems. The aim of this chapter is to provide a quantitative evaluation of the durability of materials and structures subjected to mechanical and environmental solicitations.

Published
2019
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7. The Palladium-Catalyzed Carbonylative Telomerization Reaction with Phenols, Polyphenols and Kraft Lignin

Author

Clément Dumont, Régis M. Gauvin, Mathieu Sauthier, Frederic Belva, Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille

Subjects
010405 organic chemistry, General Chemical Engineering, chemistry.chemical_element, [CHIM.CATA]Chemical Sciences/Catalysis, 010402 general chemistry, 01 natural sciences, Coupling reaction, 0104 chemical sciences, Catalysis, chemistry.chemical_compound, General Energy, Telomerization (dimerization), Nucleophile, chemistry, Environmental Chemistry, Organic chemistry, General Materials Science, Phenols, Carbonylation, ComputingMilieux_MISCELLANEOUS, Palladium, Benzoic acid
Abstract

An efficient carbonylative coupling reaction of two equivalents of 1,3-butadiene, yielding aryl nona-3,8-dienoate esters, is performed with phenols as nucleophile, and promoted by palladium-based catalysts. Optimization study reveals the key role of benzoic acid as a cocatalyst. The suggested catalyst combination enables the conversion of a wide scope of variously substituted phenols into corresponding esters with a high yield. Further tests were performed with diphenols, naturally-occurring phenols and an industrial grade Kraft lignin, thus, indicating the scope of this reaction for transforming industrially relevant polyphenolic structures.

Published
2018
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8. Étude nanométrique des propriétés piézoélectriques de composites polymère-céramique

Author

Bourez, Rudy, Ferri, Anthony, Da Costa, Antonio, Barrau, Sophie, Defebvin, J., Lefebvre, Jean Marc, Desfeux, Rachel, Unité de Catalyse et de Chimie du Solide - Site Artois (UCCS Artois), Université d'Artois (UA)-Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et de Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Unité Matériaux et Transformations - UMR 8207 (UMET), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Laboratoire de structures et propriétés de l'état solide (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, UCCS Équipe Couches Minces & Nanomatériaux, Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille-Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM]Chemical Sciences, [CHIM.MATE]Chemical Sciences/Material chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2018

9. Helium incorporation and diffusion in polycrystalline olivine

Author

Sylvie Demouchy, Mohammed Ali Bouhifd, Rémi Delon, Pete Burnard, Yves Marrocchi, Patrick Cordier, Ahmed Addad, Fabrice Barou, Centre de Recherches Pétrographiques et Géochimiques (CRPG), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Unité Matériaux et Transformations - UMR 8207 (UMET), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Laboratoire de structures et propriétés de l'état solide (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Pétrographiques et Géochimiques ( CRPG ), Université de Lorraine ( UL ) -Centre National de la Recherche Scientifique ( CNRS ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de Montpellier ( UM ) -Université des Antilles ( UA ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Magmas et Volcans ( LMV ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Institut de Recherche pour le Développement et la société-Université Clermont Auvergne ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Unité Matériaux et Transformations - UMR 8207 ( UMET ), Institut National de la Recherche Agronomique ( INRA ) -Ecole Nationale Supérieure de Chimie de Lille ( ENSCL ) -Université de Lille-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de structures et propriétés de l'état solide ( LSPES ), and Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique ( CNRS )

Subjects
010504 meteorology & atmospheric sciences, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, Thermodynamics, chemistry.chemical_element, Grain boundary, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Helium, Mantle (geology), Diffusion, Geochemistry and Petrology, Grain boundary diffusion coefficient, Polycrystalline, Incorporation, 0105 earth and related environmental sciences, [ SDU.STU.PE ] Sciences of the Universe [physics]/Earth Sciences/Petrography, Olivine, Lattice diffusion coefficient, Geology, Grain size, chemistry, 13. Climate action, engineering, Crystallite
Abstract

Helium is a key tracer of mantle geochemical and isotopic heterogeneities and can constrain our understanding of mantle geodynamics. Nevertheless, the mechanisms of helium storage and transport in mantle minerals remain poorly understood. Polycrystalline olivine was doped with helium at high temperature (1050 ± 25 °C) and high pressure (0.30 ± 0.01 GPa), followed by step heating extraction experiments to investigate helium storage and diffusion in Earth's upper mantle. We also tested the effect of heterogeneous initial concentrations on the extracted diffusivities, and demonstrate the robustness of diffusion parameters obtained in this study. Our results show that two diffusion processes are acting in polycrystalline olivine: (i) a high temperature process with high activation energy (Ea) where diffusion is only controlled by lattice diffusion, and (ii) a lower temperature process with lower Ea where diffusion is controlled by both grain boundary and lattice diffusion. These two diffusion processes are separated by a transition temperature that depends on the depletion of helium hosted in grain boundaries, i.e., the amount of helium stored at grain boundaries and the temperature and duration of the step heating sequence. Our results confirm that grain boundaries can represent a significant storage site for He. Moreover, we report two different populations of diffusion parameters in the lattice diffusion field, which are interpreted as diffusion in interstitials (Ea=95 ± 15 kJ·mol−1 and log(D0)=−8.26 ± 2.13) and Mg vacancies (Ea=168 ± 19 kJ·mol−1 and log(D0)=−3.59 ± 2.12). Similar diffusion parameters populations are observed in literature data after reprocessing the diffusivities. Furthermore, we determine grain boundary diffusion parameters: Ea=57 ± 14 kJ·mol−1 and log(D0)=−9.20 ± 0.99. Applying these results to the upper mantle reveals that an important amount of He can be stored at grain boundaries for typical mantle grain size (22% for a grain size of 1 mm) and that most helium can be stored at grain boundaries for relatively small grain sizes (≤290 μm and ≤10 μm for segregation factors of 1/10−5 and 1/0.0025, respectively). As a consequence, bulk diffusivities can be significantly higher than lattice diffusivities. Although our study cannot be applied directly to the lower mantle, the similar storage sites and diffusion mechanisms are expected in lower mantle silicates if high pressure does not inhibit diffusion.

Published
2018
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10. Visible light assisted oxidative coupling of benzylamines using heterostructured nanocomposite photocatalyst

Author

Rabah Boukherroub, Yannick Coffinier, Ahmed Addad, Abderrahmane Hamdi, Pascal Roussel, Anurag Kumar, Suman L. Jain, Department of Electrical Communication Engineering [Bangalore] (ECE), Indian Institute of Science, Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Indian Institute of Petroleum [Dehradun] (CSIR-IIP), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut d’Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520 (IEMN), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Université Polytechnique Hauts-de-France (UPHF)-Ecole Centrale de Lille-Université Polytechnique Hauts-de-France (UPHF)-Institut supérieur de l'électronique et du numérique (ISEN), Institut de Recherche Interdisciplinaire [Villeneuve d'Ascq] (IRI), Université de Lille, Sciences et Technologies-Université de Lille, Droit et Santé-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide (LSPES), Unité de Catalyse et de Chimie du Solide - UMR 8181 (UCCS), and Université d'Artois (UA)-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nanocomposite, Diffuse reflectance infrared fourier transform, 010405 organic chemistry, Scanning electron microscope, Chemistry, General Chemical Engineering, General Physics and Astronomy, General Chemistry, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, Photochemistry, 01 natural sciences, 0104 chemical sciences, symbols.namesake, X-ray photoelectron spectroscopy, Transmission electron microscopy, Photocatalysis, symbols, Raman spectroscopy, ComputingMilieux_MISCELLANEOUS, Visible spectrum
Abstract

The present paper describes a simple and direct synthesis of heterostructured nanocomposite consisting of copper(I) oxide and carbon quantum dots (Cu2O/CQD). The structure and composition of the photocatalyst were determined by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis diffuse reflectance spectroscopy and Raman spectroscopy. The synthesized photocatalyst was used for coupling of benzylamines using molecular oxygen as oxidant and house hold white LED as light emitting source under mild reaction conditions. The developed photocatalyst exhibited excellent activity, robustness and efficient recycling without any significant loss in activity for several runs.

Published
2018
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11. Effect of high Fe doping on Raman modes and optical properties of hydrothermally prepared SnO 2 nanoparticles

Author

Bernard Gelloz, Myriam Moreau, Ahmed Addad, Rabah Boukherroub, Habib Elhouichet, Brigitte Sieber, Sabine Szunerits, Walid Ben Haj Othmen, Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Spectroscopie Raman, Faculté des Sciences Mathématiques, Physiques et Naturelles de Tunis (FST), Université de Tunis El Manar (UTM)-Université de Tunis El Manar (UTM), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Faculté des Sciences de Tunis, Laboratoire de structures et propriétés de l'état solide (LSPES), Laboratoire de Spectrochimie Infrarouge et Raman - UMR 8516 (LASIR), Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Institut de Recherche Interdisciplinaire [Villeneuve d'Ascq] (IRI), Université de Lille, Sciences et Technologies-Université de Lille, Droit et Santé-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL)

Subjects
Materials science, Band gap, Scanning electron microscope, Analytical chemistry, 02 engineering and technology, 01 natural sciences, chemistry.chemical_compound, symbols.namesake, X-ray photoelectron spectroscopy, 0103 physical sciences, medicine, General Materials Science, High-resolution transmission electron microscopy, ComputingMilieux_MISCELLANEOUS, 010302 applied physics, Tin dioxide, Mechanical Engineering, 021001 nanoscience & nanotechnology, Condensed Matter Physics, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry, Mechanics of Materials, Transmission electron microscopy, symbols, Ferric, 0210 nano-technology, Raman spectroscopy, medicine.drug
Abstract

Fe-doped tin dioxide nanoparticles SnO2:Fe (x%) with x ranging from 0 to 20 were elaborated by a performed hydrothermal method. A deep structural study on the obtained nanoparticles was carried out using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The XRD measurements revealed that the rutile structure of the SnO2 was kept even for high iron concentrations. It is also observed that when iron amount increases the grain size decreases and the band gap is obviously red shifted. HRTEM imaging shows a good crystallinity of the elaborated NPs and confirm the grain size magnitude deduced from XRD measurements. The Raman modes associated to ferric phases are absent in the Fe-doped spectra which is in agreement with the XRD and HRTEM results proving the formation of SnO2:Fe solid phase. The Raman A1g mode seems to be strongly affected by the morphology transformation undergone by SnO2 NPs and by the induced local symmetry break when introducing iron. Forbidden Raman phonon modes were detected and an enhancement of the (110) surface oxygen bridging seems to follow the iron doping. This latter structural feature seems to present a major contribution to the notable enhancement of hydroxyl groups’ adsorption on the Fe-doped SnO2 surface. The variation of the Urbach energy E u with Fe amount is discussed and is found to be in accordance with the different interpretations. The PL spectra reveals that the UV-violet band of the SnO2 NPs was affected by iron presence and the induced non-systematic variation of this emission was discussed. A decrease in visible emission was noted when introducing iron revealing that Fe doping affects the density of singly charged oxygen vacancies.

Published
2018
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12. Microstructure and corrosion behavior of extruded mg-zn-er alloys

Author

Devadas Bhat Panemangalore, Rajan Ambat, Gang Ji, Manoj Gupta, Rajashekhara Shabadi, Ludovic Lesven, Ahmed Addad, Unité Matériaux et Transformations - UMR 8207 (UMET), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), National University of Singapore (NUS), Technical University of Denmark [Lyngby] (DTU), Université de Lille, Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Laboratoire de Spectrochimie Infrarouge et Raman - UMR 8516 (LASIR), Centre National de la Recherche Scientifique (CNRS)-Université de Lille, School of Metallurgy and Materials, University of Birmingham [Birmingham], Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), School of Engineering Metallurgy and Materials, Laboratoire de structures et propriétés de l'état solide (LSPES), FRE 3298 Géosystèmes, PRES Université Lille Nord de France, CNRS UMR, 8217 Géosystèmes, Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Danmarks Tekniske Universitet = Technical University of Denmark (DTU), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, [SDV]Life Sciences [q-bio], Intermetallic, chemistry.chemical_element, 02 engineering and technology, Zinc, magnesium, Corrosion, Erbium, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDV.IDA]Life Sciences [q-bio]/Food engineering, General Materials Science, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Deposition (law), ComputingMilieux_MISCELLANEOUS, corrosion, Magnesium, 020502 materials, Mechanical Engineering, Metallurgy, rare-earth, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Microstructure, Grain size, 0205 materials engineering, chemistry, Mechanics of Materials, 0210 nano-technology
Abstract

National audience; The current medical technology necessitates the usage of biodegradable metals like Magnesium (Mg) as the future implant material due to the numerous benefits it can provide. Therefore, new Magnesium-based rare earth alloys targeting biomedical applications were synthesized using Disintegrated Melt Deposition (DMD) technique followed by hot-extrusion. In this investigation, Zinc (Zn) and Erbium (Er) were chosen as alloying elements to provide suitable strengthening effect and Mg-2Zn, Mg-2Zn-2Er alloys were synthesized. With the addition of alloying elements, the grain size was reduced and several MgZn intermetallics were formed. Corrosion studies of as-extruded materials were done in 0.5 wt.% NaCl solution to elucidate the microstructure-corrosion relationship. Improved corrosion resistance is seen in the alloys in comparison to pure Magnesium. Addition of Erbium is seen to improve the protectiveness of the surface film formed during immersion. Both these elements have proven to increase the corrosion potential of Mg in NaCl solution.

Published
2018
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13. Kinetic D/H fractionation during hydration and dehydration of silicate glasses, melts and nominally anhydrous minerals

Author

Christophe Depecker, Hugues Leroux, Jannick Ingrin, Laurent Remusat, Mathieu Roskosz, Didier Laporte, Etienne Deloule, Sébastien Merkel, Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Université de Lille, ENSCL, CNRS, INRA, Unité Matériaux et Transformations - UMR 8207 [UMET], Centre de Recherches Pétrographiques et Géochimiques [CRPG], Laboratoire Magmas et Volcans [LMV], Institut de minéralogie, de physique des matériaux et de cosmochimie [IMPMC], Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire de minéralogie du Muséum National d'Histoire Naturelle (LMMNHN), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Laboratoire de structures et propriétés de l'état solide (LSPES), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, 010504 meteorology & atmospheric sciences, Hydrogen, Analytical chemistry, chemistry.chemical_element, Volcanology, 010502 geochemistry & geophysics, 01 natural sciences, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Fluid inclusions, Total pressure, 0105 earth and related environmental sciences, Aqueous solution, Grossular, Hydration/dehydration of minerals, D/H fractionation, Deuterium, chemistry, Cosmochemistry, 13. Climate action, visual_art, visual_art.visual_art_medium, Anhydrous, [CHIM.OTHE]Chemical Sciences/Other, Single crystal, Kinetic isotope fractionation
Abstract

International audience; The distribution of hydrogen isotopes during diffusion-driven aqueous processes in silicate glasses, melts and crystals was investigated. Hydration/dehydration experiments were performed on silica glasses at 1000 °C and 1 bar total pressure. Dehydration triggered by decompression-driven bubble nucleation and growth was performed on rhyolitic melts at 800 °C and a few hundred MPa. Hydrogen extraction from a nominally anhydrous mineral (grossular) single crystal was carried out at 800 °C and ambient pressure. After these three series of experiments, pronounced water (sensu lato) concentration profiles were observed in all recovered samples. In the grossular single-crystal, a large spatial variation in H isotopes (δD variation > 550‰) was measured across the sample. This isotopic distribution correlates with the hydrogen extraction profile. The fit to the data suggests an extreme decoupling between hydrogen and deuterium diffusion coefficients (DH and DD respectively), akin to the decoupling expected in a dilute ideal gas (DH/DD ≈ 1.41). Conversely, no measurable spatially- and time-resolved isotopic variations were measured in silicate glasses and melts. This contrasted behavior of hydrogen isotopes likely stands in the different water speciation and solution mechanisms in the three different materials. Glasses and melts contain essentially hydroxyl and molecular water groups but the mobile species is molecular water in both cases. Protonated defects make up most of the water accommodated in grossular and other nominally anhydrous minerals (NAM). These defects are also the mobile species that diffuse against polarons. These results are crucial to accurately model the degassing behavior of terrestrial and lunar magmas and to derive the initial D/H of water trapped in fluid inclusions commonly analyzed in mantle NAMs, which suffered complex geological histories.

Published
2018
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14. Pure climb creep mechanism drives flow in Earth’s lower mantle

Author

Pierre Hirel, Karine Gouriet, Philippe Carrez, Francesca Boioli, Sebastian Ritterbex, Antoine Kraych, Patrick Cordier, Benoit Devincre, Unité Matériaux et Transformations - UMR 8207 (UMET), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Laboratoire de structures et propriétés de l'état solide (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'étude des microstructures [Châtillon] (LEM - ONERA - CNRS), ONERA-Centre National de la Recherche Scientifique (CNRS), Laboratoire Lasers, Plasmas et Procédés photoniques (LP3), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), European Project: 290424,EC:FP7:ERC,ERC-2011-ADG_20110209,RHEOMAN(2012), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Centre National de la Recherche Scientifique (CNRS)-ONERA, Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Dislocation creep, Seismic anisotropy, Multidisciplinary, Materials science, 010504 meteorology & atmospheric sciences, Silicate perovskite, Mineralogy, Diffusion creep, SciAdv r-articles, Geology, Mechanics, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Mantle convection Creep mechanism bridgmanite, Mantle (geology), Ringwoodite, Creep, engineering, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Climb, Research Articles, 0105 earth and related environmental sciences, Research Article
Abstract

Climb creep provides an efficient deformation mechanism for bridgmanite under lower mantle conditions., At high pressure prevailing in the lower mantle, lattice friction opposed to dislocation glide becomes very high, as reported in recent experimental and theoretical studies. We examine the consequences of this high resistance to plastic shear exhibited by ringwoodite and bridgmanite on creep mechanisms under mantle conditions. To evaluate the consequences of this effect, we model dislocation creep by dislocation dynamics. The calculation yields to an original dominant creep behavior for lower mantle silicates where strain is produced by dislocation climb, which is very different from what can be activated under high stresses under laboratory conditions. This mechanism, named pure climb creep, is grain-size–insensitive and produces no crystal preferred orientation. In comparison to the previous considered diffusion creep mechanism, it is also a more efficient strain-producing mechanism for grain sizes larger than ca. 0.1 mm. The specificities of pure climb creep well match the seismic anisotropy observed of Earth’s lower mantle.

Published
2017
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15. Rigid amorphous fraction versus oriented amorphous fraction in uniaxially drawn polyesters

Author

Allisson Saiter, Eric Dargent, V. Miri, F. Hamonic, Laboratoire d’Etude et de Caractérisation des Amorphes et des Polymères (AMME-LECAP EA 4528 International Laboratory), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), and Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies

Subjects
[PHYS]Physics [physics], Materials science, Polymers and Plastics, Scattering, Organic Chemistry, Isotropy, General Physics and Astronomy, Copolyester, Amorphous solid, Crystal, Polyester, Differential scanning calorimetry, Phase (matter), [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Materials Chemistry, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], Composite material, ComputingMilieux_MISCELLANEOUS
Abstract

Structural changes in poly(ethylene terephthalate) PET and the copolyester poly(ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate) PETg occurring during uniaxially drawing at 100 °C have been investigated as a function of draw ratio. This work compares the “microstructural” and the “thermodynamic” three phase description of drawn polyester films. Using Wide angle X-ray Scattering, both materials were characterized considering crystals, isotropic and oriented amorphous phases. Temperature Modulated Differential Scanning Calorimetry allows to evaluate the fraction of crystals, mobile and rigid amorphous fractions (MAP and RAF respectively). Above a critical draw ratio, RAF appears as soon as a strain induced crystalline (SIC) phase is developed for both materials. The degree of crystalline phase is lower and takes place at higher draw ratio for PETg than for PET. For PET, the oriented amorphous phase is composed by the RAF and a part of the MAP. For PETg, the SIC takes place in PET-rich regions and the quantity of RAF per crystal is high.

Published
2014
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16. Micromechanics-based constitutive modeling of plastic yielding and damage mechanisms in polymer–clay nanocomposites: Application to polyamide-6 and polypropylene-based nanocomposites

Author

Kokou Anoukou, Ali Zaoui, M. Naït-Abdelaziz, Zhengwei Qu, Jean-Marc Lefebvre, Jean-Michel Gloaguen, A. Mesbah, Taoufik Boukharouba, Fahmi Zaïri, Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Laboratoire Génie Civil et Géo-Environnement [Béthune] (LGCgE), Université d'Artois (UA), and Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
B. Porosity/voids, Materials science, C. Modeling, Crazing, B. Plastic deformation, 02 engineering and technology, engineering.material, 010402 general chemistry, 01 natural sciences, Polymer clay, chemistry.chemical_compound, Ultimate tensile strength, Composite material, B. Debonding, Polypropylene, A. Nanocomposites, Nanocomposite, General Engineering, Micromechanics, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Montmorillonite, chemistry, Deformation mechanism, Ceramics and Composites, engineering, 0210 nano-technology
Abstract

International audience; The present work focuses on the continuum-based micromechanical modeling of the elastic-plastic stress-strain response including damage mechanisms of polymer-clay nanocomposites. The micromechanical elastic-plastic-damage model includes both the actual microstructure of the said composites using a multi-scale approach and the microstructural evolution related to damage accumulation under applied macroscopic deformation. The interfacial debonding between clay nanoparticles and polymer matrix, and the polymer matrix voiding are the two prevalent damage events considered. The tensile stress-strain response and micromechanical deformation processes of polyamide-6 and polypropylene-based systems reinforced with modified montmorillonite clay at various concentrations are experimentally investigated by a video-controlled technique. The usual shear yielding deformation mode of neat polyamide-6 is altered by the presence of clay platelets which induce a dilatational process due to interfacial debonding. In addition to matrix shear yielding, a dual-dilatational deformation mechanism by crazing and interfacial debonding is revealed in polypropylene-clay nanocomposites. Using the intrinsic deformation micromechanisms and elastic-plastic properties of the polymer matrix, and the nanocomposite structural characteristics, the micromechanical model is found to successfully describe the experimental results of the two nanocomposite materials in terms of tensile stress-strain response and inelastic volumetric strain.

Published
2014
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17. A micromechanical model taking into account the contribution of α- and γ-crystalline phases in the stiffening of polyamide 6-clay nanocomposites: A closed-formulation including the crystal symmetry

Author

Ali Zaoui, M. Naït-Abdelaziz, Zhengwei Qu, Jean-Michel Gloaguen, Fahmi Zaïri, Kokou Anoukou, Jean-Marc Lefebvre, Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire Génie Civil et Géo-Environnement [Béthune] (LGCgE), Université d'Artois (UA), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), and Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
B. Interface/interphase, Materials science, Nanocomposite, Mechanical Engineering, Stiffness, Crystal structure, Microstructure, Industrial and Manufacturing Engineering, Amorphous solid, Stiffening, A. Polymer-matrix composites (PMCs), chemistry.chemical_compound, B. Anisotropy, Montmorillonite, chemistry, Mechanics of Materials, A. Nano-structures, C. Micromechanics, Ceramics and Composites, medicine, Composite material, medicine.symptom, Monoclinic crystal system
Abstract

International audience; A clay-induced crystal transformation has been widely pointed out in semi-crystalline polymer-clay nanocomposites, from the α-form to the γ-form in the particular case of polyamide 6 (PA6). The proposition of a predictive model taking explicitly into account the polymer crystalline structure is still needed for a reliable prediction of the structure-property relationship and for a better understanding of the reinforcement mechanism in such systems. The aim of this paper is to present an approach issued from the continuum-based micromechanical framework using self-consistency condition to predict the overall stiffness of PA6-clay nanocomposites. Besides the effect of clay particle characteristics, the micromechanical model introduces the contribution of α- and γ-form crystals in the overall stiffness by considering the PA6 matrix as a heterogeneous medium containing distinct amorphous and crystalline phases. A closed-formulation of the micromechanical model is derived using the Walpole spectral decomposition of the stiffness tensors for the two monoclinic crystalline phases. Two possible representations of the microstructure are considered: the first one considers that all the phases are independent and the second one that the γ-crystalline phase constitutes an interphase region around clay particles. The micromechanical model using the two morphological representations is used to predict the overall stiffness of PA6 nanocomposites reinforced with montmorillonite clay (adjusted from 1 wt% up to 20 wt%) for which the polymer crystalline structure was characterized by infrared spectroscopy and calorimetry. The respective role of clay particles and of two crystalline species in the stiffening of exfoliated and intercalated PA6-clay nanocomposites is discussed with respect to the micromechanical model.

Published
2014
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18. A visco-hyperelastic damage model for cyclic stress-softening, hysteresis and permanent set in rubber using the network alteration theory

Author

Georges Ayoub, Jean-Michel Gloaguen, Fahmi Zaïri, M. Naït-Abdelaziz, Ghassan T. Kridli, Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies

Subjects
chemistry.chemical_classification, Cyclic stress, Materials science, business.industry, Mechanical Engineering, Constitutive equation, Polymer, Structural engineering, A. Hysteresis, A. Cyclic stress-softening, A. Permanent set, Hysteresis, C. Network alteration theory, chemistry, Natural rubber, Mechanics of Materials, Hyperelastic material, visual_art, B. Elastomeric materials, visual_art.visual_art_medium, General Materials Science, Composite material, business, Constant (mathematics), Softening
Abstract

International audience; The large deformation time-dependent mechanical response of rubber-like materials under cyclic loading is characterized by stress-softening, hysteresis and permanent set. To describe this set of first-order phenomena a constitutive model integrating the physics of polymer chains and their alteration under cyclic loading is proposed. The time-dependency is considered using a Zener-type framework in which the chain extensibility limit is described with both physical and phenomenological approaches. The efficiency of the proposed constitutive model is illustrated by comparisons with experimental data obtained on a styrene-butadiene rubber submitted to cyclic tension loading up to failure both in constant and variable amplitudes.

Published
2014
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19. Modeling plasticity of MgO by 2.5D dislocation dynamics simulations

Author

Reali, Riccardo, Boioli, Francesca, Gouriet, Karine, Carrez, Philippe, Devincre, Benoit, Cordier, Patrick, Unité Matériaux et Transformations - UMR 8207 (UMET), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Laboratoire Lasers, Plasmas et Procédés photoniques (LP3), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Laboratoire de structures et propriétés de l'état solide (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'étude des microstructures [Châtillon] (LEM - ONERA - CNRS), ONERA-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Centre National de la Recherche Scientifique (CNRS)-ONERA, Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Periclase, Materials Science(all), Mechanics of Materials, 2.5D dislocation dynamics, Mechanical Engineering, High-temperature plasticity, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], MgO, Creep, Condensed Matter Physics
Abstract

International audience; In this study, we model the plasticity of MgO (periclase) using a 2.5-dimensional (2.5D) dislocation dynamics (DD) simulation approach. This model allows us to incorporate climb in DD simulations to model the creep behavior at high-temperature. Since a 2D formulation of DD cannot capture some important features of dislocation activity (e.g. those involving line tension), local rules are introduced to take these features into account (this is the 2.5D approach). To ensure the validity of such approach, the model is applied over a wide temperature range with a view in the lower temperature regimes where the newly introduced mechanism (climb) is not active, to benchmark our model against previous 3D simulations and experimental data. Thus we consider successfully a low temperature (T ≤600 K) regime where plasticity is dominated by dislocation glide in the thermally activated regime; an intermediate regime (T =1000 K) where plasticity is dominated by dislocation-dislocation interactions; and a high-temperature regime (1500≤T ≤1800 K) which is the actual goal of the present study and where creep plasticity is governed by dislocation glide controlled by recovery (climb being considered here). We show that, taking into account the range of oxygen self-diffusion coefficients available in the literature, our simulations are able to describe properly the high-temperature creep behavior of MgO.

Published
2017
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20. Textures in deforming forsterite aggregates up to 8 GPa and 1673 K

Author

Fabrice Detrez, Olivier Castelnau, Caroline Bollinger, Sébastien Merkel, Paul Raterron, Unité Matériaux et Transformations - UMR 8207 (UMET), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Propriétés mécaniques et thermodynamiques des matériaux (PMTM), Centre National de la Recherche Scientifique (CNRS), Laboratoire de Modélisation et Simulation Multi Echelle (MSME), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Paris-Est Marne-la-Vallée (UPEM), Science Terre, Univers, Espace, Institut Universitaire de France, Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies, HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM), Université Paris-Est Marne-la-Vallée (UPEM)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Consortium for Materials Properties Research in Earth Sciences (COMPRES) under NSF [EAR 06-49658], Agence Nationale de la Recherche (ANR) [BLAN08-2_343541], U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences [DE-AC02-98CH10886], Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Laboratoire de structures et propriétés de l'état solide (LSPES), Procédés et Ingénierie en Mécanique et Matériaux [Paris] (PIMM), École Nationale Supérieure d'Arts et Métiers (ENSAM), Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Arts et Métiers Sciences et Technologies, and HESAM Université (HESAM)-HESAM Université (HESAM)-Centre National de la Recherche Scientifique (CNRS)-Conservatoire National des Arts et Métiers [CNAM] (CNAM)

Subjects
Seismic anisotropy, Micromechanical modeling, 010504 meteorology & atmospheric sciences, Mineralogy, Slip (materials science), engineering.material, Sciences de l'ingénieur, 010502 geochemistry & geophysics, 01 natural sciences, Mantle (geology), [SPI]Engineering Sciences [physics], Geochemistry and Petrology, [SPI.MECA.MEMA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of materials [physics.class-ph], General Materials Science, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Olivine, Viscoplasticity, Condensed matter physics, Chemistry, Forsterite, D-DIA, D-DIA - Deformation - Forsterite - High pressure - Lattice preferred orientation - Micromechanical modeling, Lattice preferred orientation, Deformation, High pressure, Amplitude, 13. Climate action, engineering
Abstract

International audience; We report results from axisymmetric deformation experiments carried out on forsterite aggregates in the deformation-DIA apparatus, at upper mantle pressures and temperatures (3.1-8.1 GPa, 1373-1673 K). We quantified the resulting lattice preferred orientations (LPO) and compare experimental observations with results from micromechanical modeling (viscoplastic second-order self-consistent model-SO). Up to 6 GPa (similar to 185-km depth in the Earth), we observe a marked LPO consistent with a dominant slip in the (010) plane with one observation of a dominant [100] direction, suggesting that [100](010) slip system was strongly activated. At higher pressures (deeper depth), the LPO becomes less marked and more complex with no evidence of a dominant slip system, which we attribute to the activation of several concurrent slip systems. These results are consistent with the pressure-induced transition in the dominant slip system previously reported for olivine and forsterite. They are also consistent with the decrease in the seismic anisotropy amplitude observed in the Earth's mantle at depth greater than similar to 200 km.

Published
2016
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21. Fatigue life prediction of rubber-like materials under multiaxial loading using a continuum damage mechanics approach: Effects of two-blocks loading and R ratio

Author

Jean-Michel Gloaguen, Georges Ayoub, M. Naït-Abdelaziz, Fahmi Zaïri, Pierre Charrier, Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Trelleborg Modyn, Trelleborg, and Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, 02 engineering and technology, Cracking energy density, Multiaxial fatigue life, 0203 mechanical engineering, Natural rubber, General Materials Science, Instrumentation, Rubber-like materials, Strain energy release rate, Variable amplitude, Ogden, Continuum damage mechanics, business.industry, Torsion (mechanics), Strain energy density function, Structural engineering, 021001 nanoscience & nanotechnology, Cracking, 020303 mechanical engineering & transports, Amplitude, R ratio, Mechanics of Materials, visual_art, Hyperelastic material, visual_art.visual_art_medium, 0210 nano-technology, business
Abstract

International audience; This contribution presents a continuum damage mechanics model for the high-cycle fatigue life prediction of rubber-like materials. The proposed model is an extension of that proposed by Wang et al. (2002) for multiaxial loadings. The damage strain energy release rate is first derived from a generalized Ogden strain energy density and then from the cracking energy density. A new multiaxial fatigue predictor is proposed and presented in its most general form with the aim of being applicable to all hyperelastic materials. The effects of variable amplitude and mean stretch are explicitly accounted for in the damage evolution law. The fatigue damage behavior of a carbon-filled styrene-butadiene rubber is experimentally investigated under tension, torsion and combined tension-torsion loadings both in constant and variable amplitudes, including the effects of different R ratios (i.e. different minimum and maximum stretches). The proposed model, which requires few damage parameters to be identified, is used to predict the number of cycles to failure and, a satisfactory agreement between predicted values and experimental data is clearly highlighted for the different loading paths.

Published
2012
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22. Micromechanical Modeling of the Effective Viscoelastic Response of Polyamide-6-Based Nanocomposites Reinforced with Modified and Unmodified Montmorillonite Clay

Author

Ali Zaoui, Jean-Michel Gloaguen, M. Nait-Abdelaziz, Kokou Anoukou, Fahmi Zaïri, Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), and Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Micromechanical Modeling, 02 engineering and technology, Structure-Property Relationship, 010402 general chemistry, 01 natural sciences, Viscoelasticity, chemistry.chemical_compound, medicine, General Materials Science, Composite material, Polymer/Clay Nanocomposites, chemistry.chemical_classification, Nanocomposite, Mechanical Engineering, Stiffness, Micromechanics, Polymer, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Exfoliation joint, 0104 chemical sciences, Montmorillonite, chemistry, Mechanics of Materials, Polyamide, medicine.symptom, 0210 nano-technology
Abstract

A micromechanics-based approach using a self-consistent scheme based on the double-inclusion model is adopted to develop a pertinent model for describing the viscoelastic response of polymer/clay nanocomposites. The relationship between the intercalated nanostructure and the effective nanocomposite stiffness is constructed using an equivalent stiffness method in which the clay stacks are replaced by homogeneous nanoparticles with predetermined equivalent anisotropic stiffness. The capabilities of the proposed micromechanics-based model are checked by comparing with the experimental viscoelastic (glassy to rubbery) response of two polyamide-6-based nanocomposite systems reinforced with a modified montmorillonite clay (Cloisite 30B) and an unmodified sodium montmorillonite clay (Cloisite Na+), favoring, respectively, exfoliation and intercalation states.

Published
2012
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23. Plasticity/damage coupling in semi-crystalline polymers prior to yielding: Micromechanisms and damage law identification

Author

Sabine Cantournet, Roland Séguéla, Fabrice Detrez, Centre des Matériaux (MAT), MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies, and Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Plasticity, Polymers and Plastics, Generalized Maxwell model, Organic Chemistry, 02 engineering and technology, Dynamic mechanical analysis, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Viscoelasticity, [SPI.MAT]Engineering Sciences [physics]/Materials, 0104 chemical sciences, Damage, Lamella (surface anatomy), Ultimate tensile strength, Materials Chemistry, Composite material, 0210 nano-technology, Semi-crystalline polymer, Elastic modulus, Tensile testing
Abstract

International audience; This work addresses the question of the intimate coupling of plastic and damaging processes during the deformation of semi-crystalline polymers at small strains. The evolution of the spherulitic structure in the pre-yield strain range under tensile testing is investigated by atomic force microscopy for three semi-crystalline polymers, namely polycaprolactone, poly(1-butene) and polyamide 6. These materials have different spherulite size, crystallinity index and lamella thickness, and different glass transition temperature of the amorphous phase. Strain-induced damage is clearly evidenced through the gradual loss of elastic properties upon cyclic tensile tests, since the early stage of stretching. In parallel, volume strain appears to be about nil up to the yield point for the three polymers. AFM reveals that fragmentation of the crystalline lamellae occurs well before the yield strain at room temperature, starting about the core region of the spherulites and extending towards the periphery, for all polymers. This is claimed as evidence that lamella fragmentation is a basic mechanism of damage without significant cavitation at low strain. An approach of damage modeling is carried out via preliminary assessment of the viscoelastic contribution from low strain dynamic mechanical analysis using a generalized Maxwell model. It is shown that computing the viscoelastic contribution in the strain range up to yielding, in the assumption of linearity, fairly account for the loading-unloading hysteresis of the tensile cycles. A phenomenological plasticity/damage coupling law is established from the elastic modulus drop with increasing plastic strain, both assessed from the "relaxed" tensile cycles. The same kind of law is shown to apply for the three polymers. A physical meaning to the phenomenological law is proposed via a simple model of fiber rupture in single-fiber-reinforced composite.

Published
2011
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24. Modeling the low-cycle fatigue behavior of visco-hyperelastic elastomeric materials using a new network alteration theory: Application to styrene-butadiene rubber

Author

Fahmi Zaïri, Georges Ayoub, Jean-Michel Gloaguen, M. Naït-Abdelaziz, Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), and Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, 02 engineering and technology, Elastomer, Stress (mechanics), 0203 mechanical engineering, Natural rubber, Network alteration theory, Composite material, Fatigue, Mullins effect, Hysteresis, Mechanical Engineering, Mechanics, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Nonlinear system, 020303 mechanical engineering & transports, Elastomeric materials, Mechanics of Materials, visual_art, Hyperelastic material, visual_art.visual_art_medium, Visco-hyperelasticity, 0210 nano-technology, Vibration fatigue
Abstract

International audience; Although several theories were more or less recently proposed to describe the Mullins effect, i.e. the stress-softening after the first load, the nonlinear equilibrium and non-equilibrium material response as well as the continuous stress-softening during fatigue loading need to be included in the analysis to propose a reliable design of rubber structures. This contribution presents for the first time a network alteration theory, based on physical interpretations of the stress-softening phenomenon, to capture the time-dependent mechanical response of elastomeric materials under fatigue loading, and this until failure. A successful physically based visco-hyperelastic model is revisited by introducing an evolution law for the physical material parameters affected by the network alteration. The general form of the model can be basically represented by two parallel networks: a nonlinear equilibrium response and a time-dependent deviation from equilibrium, in which the network parameters become functions of the damage rate (defined as the ratio of the applied cycle over the applied cycle to failure). The mechanical behavior of styrene-butadiene rubber was experimentally investigated, and the main features of the constitutive response under fatigue loading are highlighted. The experimental results demonstrate that the evolution of the normalized maximum stress only depends on the damage rate endured by the material during the fatigue loading history. The average chain length and the average chain density are then taken as functions of the damage rate in the proposed network alteration theory. The new model is found to adequately capture the important features of the observed stress–strain curves under loading–unloading for a large spectrum of strain and damage levels. The model capabilities to predict variable amplitude tests are critically discussed by comparisons with experiments.

Published
2011
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25. On the overall elastic moduli of polymer–clay nanocomposite materials using a self-consistent approach. Part I: Theory

Author

Fahmi Zaïri, Kokou Anoukou, Jean-Michel Gloaguen, Ali Zaoui, M. Naït-Abdelaziz, Tanguy Messager, Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), and Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Length scale, Materials science, C. Modeling, Interactions, A. Nanoclays, 02 engineering and technology, engineering.material, 010402 general chemistry, 01 natural sciences, Homogenization (chemistry), Moduli, Polymer clay, Transverse isotropy, Composite material, Elastic modulus, Nanoscopic scale, B. Mechanical properties, A. Nanocomposites, Nanocomposite, General Engineering, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Condensed Matter::Soft Condensed Matter, Ceramics and Composites, engineering, 0210 nano-technology
Abstract

International audience; Although few investigations recently proposed to describe the overall elastic response of polymer–clay nanocomposite materials using micromechanical-based models, the applicability of such models for nanocomposites is far from being fully established. The main point of criticism to mention is the shelving of crucial physical phenomena, such as interactions and length scale effects, generally associated by material scientists, in addition to the nanofiller aspect ratio, to the remarkable mechanical property enhancement of polymer–clay nanocomposites. In this Part I of two-part paper, we present a micromechanical approach for the prediction of the overall moduli of polymer–clay nanocomposites using a self-consistent scheme based on the double-inclusion model. This approach is used to account for the inter-inclusion and inclusion–matrix interactions. Although neglected in the models presented in the literature, the active interaction between the nanofillers should play a key role in the reinforcing effect of nano-objects dispersed in a polymer matrix. The present micromechanical model incorporates the nanostructure of clay stacks, modeled as transversely isotropic spheroids, and the so-called constrained region, modeled as an interphase around reinforcements. This latter is linked to the interfacial interaction between matrix and reinforcements that forms a region where the polymer chain mobility is reduced. To account for length scale effects, interphase thickness and particle dimensions are taken as explicit model parameters. Instead of solving iteratively the basic homogenization equation of the self-consistent scheme, our formulation yields to a pair of equations that can be solved simultaneously for the overall elastic moduli of composite materials. When the interphase is disregarded for spheroids with zero aspect ratio, our formulation coincides with the Walpole solution (J Mech Phys Solids 1969;17:235–251). Using the proposed general form, a parametric study is presented to analyze the respective influence of aspect ratio, number of silicate layers, interlayer spacing and nanoscopic size of the transversely isotropic spheroids on the overall elastic moduli of nanocomposite materials.

Published
2011
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26. Superplasticity of a Fine-Grained TZ3Y Material Involving Dynamic Grain Growth and Dislocation Motion

Author

Guillaume Bernard-Granger, Christian Guizard, Ahmed Addad, laboratoire de synthèse et fonctionnalisation des céramiques (LSFC), SAINT-GOBAIN-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), and Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies

Subjects
010302 applied physics, Materials science, Metallurgy, Diffusion creep, Superplasticity, [CHIM.MATE]Chemical Sciences/Material chemistry, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Grain size, Grain growth, Creep, 0103 physical sciences, Materials Chemistry, Ceramics and Composites, Grain boundary, Composite material, 0210 nano-technology, Grain boundary strengthening, Grain Boundary Sliding
Abstract

International audience; Superplastic deformation of a fully dense TZ3Y material, having a starting grain size around 135–145 nm and depleted of any amorphous phase at grain boundaries, has been investigated using compressive creep tests in air in the temperature range of 1100°–1300°C and the real stress range of 50–100 MPa. The key parameters of the creep law have been determined by performing temperature changes at a fixed stress and stress jumps at a fixed temperature. From such experiments, an average value for the apparent stress exponent of around 3 is obtained when the applied stress varied from 50 to 100 MPa and the temperature was kept constant in the range of 1100°–1300°C. The apparent activation energy of the mechanism controlling the creep deformation is evaluated at 577±75 kJ/mol in the temperature range of 1200°–1300°C, for a real stress of 70 MPa. The values of the apparent grain size exponent can be calculated from the initial grain size in the as-sintered samples and the grain size in the crept samples. In all cases, it was determined to be around 2. Observation of the microstructure of the crept samples, using scanning electron microscopy, reveals grain growth but does not show any significant elongation of the elemental grains. Transmission electron microscopy of a sample crept under 100 MPa at 1300°C reveals clear intragranular dislocation activity. This dislocation activity seems to be mainly confined in folds emitted at triple points. Because the creep parameters (experimental and calculated using a simple geometric model) and the microstructure observed are in good agreement, we propose that the creep mechanism involved is grain boundary sliding accommodated by dynamic grain growth and the formation of triple-point folds.

Published
2010
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27. Modelling of photodegradation effect on elastic–viscoplastic behaviour of amorphous polylactic acid films

Author

Mohamed Benguediab, Fahmi Zaïri, S. Belbachir, Ulrich Maschke, Jean-Marc Lefebvre, M. Naït-Abdelaziz, Jean-Michel Gloaguen, Georges Ayoub, Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), and Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Polymeric material, Materials science, Elastic–viscoplastic modelling, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Gel permeation chromatography, chemistry.chemical_compound, stomatognathic system, Polylactic acid, Photodegradation, Irradiation, Composite material, chemistry.chemical_classification, Viscoplasticity, Mechanical Engineering, technology, industry, and agriculture, Chemical modification, Polymer, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, Amorphous solid, chemistry, Mechanics of Materials, Finite strain, 0210 nano-technology
Abstract

International audience; Polylactic acid (PLA) films were subjected to accelerated ultra-violet (UV) ageing. The UV irradiation leads to the alteration of the chemical structure which influences directly the mechanical response of the polymer. The chemical modification of the polymer was followed by gel permeation chromatography. Uniaxial tension tests were conducted at 50 °C and for different strain rates in order to characterize the large deformation response of PLA. The influence of UV irradiation on the alteration of the large deformation response of PLA was examined. A physically based elastic–viscoplastic model was used to describe the mechanical response of virgin PLA. The photodegradation effect was incorporated into the constitutive model to capture the stress–strain behaviour up to failure of aged PLA. To that end, the measured molecular weight was used as a direct input into the model. The model is shown to be in good agreement with experimental results over a wide range of UV irradiation doses.

Published
2010
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28. Controlled Growth of SnO2 Nanocrystals in Eu3+-Doped SiO2−SnO2 Planar Waveguides: A Spectroscopic Investigation

Author

Bruno Capoen, B. N. Shivakiran Bhaktha, Maurizio Ferrari, Mohamed Bouazaoui, Franck Beclin, Pascal Roussel, Odile Robbe-Cristini, Christophe Kinowski, Sylvia Turrell, Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), CSMFO group, Physics Department, Povo-trento, Laboratoire de physique de la matière condensée (LPMC), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes et de Recherches Lasers et Applications (CERLA), Université de Lille, Sciences et Technologies, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Université Nice Sophia Antipolis (... - 2019) (UNS), and Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille

Subjects
Photoluminescence, Materials science, Analytical chemistry, Infrared spectroscopy, 02 engineering and technology, 01 natural sciences, law.invention, Crystal, Tetragonal crystal system, symbols.namesake, Optics, law, 0103 physical sciences, Physical and Theoretical Chemistry, Crystallization, 010302 applied physics, business.industry, 021001 nanoscience & nanotechnology, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, General Energy, Transmission electron microscopy, Rutile, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], symbols, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], 0210 nano-technology, business, Raman scattering
Abstract

We report on the fabrication of Eu3+-doped SiO2−SnO2 low-loss (0.8 dB/cm at 632.8 nm) glass-ceramic planar waveguides, fabricated by the sol−gel technique and dip-coating processing. The effects of heat treatments on the growth and evolution of SnO2 nanocrystals in the matrix were investigated using different spectroscopic tools. In situ high-temperature X-ray diffraction allowed for the determination of the crystallization temperature and confirmed the formation of tetragonal rutile SnO2 crystals. The effect of crystallization on the optical properties and on the photoluminescence of Eu3+ ions was also studied. Low-frequency Raman scattering was successfully used to determine the crystal size, and the results obtained were found to be consistent with transmission electron microscopy measurements. The breakage of Si−O−Sn linkages during the formation of SnO2 nanocrystals in the matrix was investigated by Fourier-transform infrared spectroscopy.

Published
2009
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29. Transformation of medical grade silicone rubber under Nd:YAG and excimer laser irradiation: First step towards a new miniaturized nerve electrode fabrication process

Author

D. Derozier, O. Robbe, Ahmed Addad, Sylvia Turrell, C. Dupas-Bruzek, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes et de Recherches Lasers et Applications (CERLA), Université de Lille, Sciences et Technologies, Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, medicine.medical_treatment, General Physics and Astronomy, 02 engineering and technology, 010402 general chemistry, Silicone rubber, 01 natural sciences, law.invention, chemistry.chemical_compound, Optics, law, medicine, chemistry.chemical_classification, Excimer laser, business.industry, Surfaces and Interfaces, General Chemistry, Polymer, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Laser, 0104 chemical sciences, Surfaces, Coatings and Films, Surface micromachining, chemistry, Electrode, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, Surface modification, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Metallizing, 0210 nano-technology, business
Abstract

Medical grade silicone rubber, poly-dimethylsiloxane (PDMS) is a widely used biomaterial. Like for many polymers, its surface can be modified in order to change one or several of its properties which further allow this surface to be functionalized. Laser-induced surface modification of PDMS under ambient conditions is an easy and powerful method for the surface modification of PDMS without altering its bulk properties. In particular, we profit from both UV laser inducing surface modification and of UV laser micromachining to develop a first part of a new process aiming at increasing the number of contacts and tracks within the same electrode surface to improve the nerve selectivity of implantable self sizing spiral cuff electrodes. The second and last part of the process is to further immerse the engraved electrode in an autocatalytic Pt bath leading in a selective Pt metallization of the laser irradiated tracks and contacts and thus to a functionalized PDMS surface. In the present work, we describe the different physical and chemical transformations of a medical grade PDMS as a function of the UV laser and of the irradiation conditions used. We show that the ablation depths, chemical composition, structure and morphology vary with (i) the laser wavelength (using an excimer laser at 248 nm and a frequency-quadrupled Nd:YAG laser at 266 nm), (ii) the conditions of irradiation and (iii) the pulse duration. These different modified properties are expected to have a strong influence on the nucleation and growth rates of platinum which govern the adhesion and the thickness of the Pt layer on the electrodes and thus the DC resistance of tracks.

Published
2009
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30. Numerical modelling of dislocations and deformation mechanisms in CaIrO3 and MgGeO3 post-perovskites—Comparison with MgSiO3 post-perovskite

Author

David Mainprice, Philippe Carrez, Patrick Cordier, Arnaud Metsue, Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Géosciences Montpellier, and Université des Antilles et de la Guyane (UAG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, 010504 meteorology & atmospheric sciences, Physics and Astronomy (miscellaneous), Post-perovskite, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, Dislocations, MgGeO3, 010502 geochemistry & geophysics, 01 natural sciences, Peierls–Nabarro model, Deformation mechanisms, 0105 earth and related environmental sciences, Slip systems, Dislocation creep, Condensed matter physics, Astronomy and Astrophysics, First-principle calculations, CaIrO3, Crystallography, MgSiO3, Geophysics, Deformation mechanism, Space and Planetary Science, Crystallite, Dislocation, Deformation (engineering), Single crystal, Stacking fault
Abstract

International audience; In this study, we propose a theoretical approach to test the validity of the isomechanical analogues for post-perovskite structures. Intrinsic plastic properties are evaluated for three materials exhibiting a post-perovskite phase: MgSiO3, MgGeO3 and CaIrO3. Dislocation properties of each structure are determined using the Peierls-Nabarro model based on first-principles calculations of generalised stacking fault and the plastic properties are extended to crystal-preferred orientations using a visco-plastic self-consistent method. This study provides intrinsic parameters of plastic deformation such as dislocation structures and Peierls stresses that can be directly compared between the three materials. It appears that it is very difficult to draw any simple conclusions on polycrystalline deformation simply by comparing single crystal properties. In particular, contrasting single crystal properties of MgSiO3 and CaIrO3 lead to similar crystal-preferred orientation of the polycrystal aggregates.

Published
2009
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31. Electrochemical impedance spectroscopy of ZnO nanostructures

Author

Wenguo Xu, Pascal Roussel, Rabah Boukherroub, Brigitte Sieber, Jacky Laureyns, Hongqin Liu, Sabine Szunerits, Gaëlle Piret, The Institute for Chemical Physics, Beijing Institute of Technology (BIT), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), and Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille

Subjects
Scanning electron microscope, Annealing (metallurgy), Inorganic chemistry, Nanowire, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Annealing, lcsh:Chemistry, Metal, chemistry.chemical_compound, Electrochemistry, Aqueous solution, Chemistry, Doping, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Lithium perchlorate, 0104 chemical sciences, Dielectric spectroscopy, lcsh:Industrial electrochemistry, lcsh:QD1-999, visual_art, visual_art.visual_art_medium, ZnO nanowires, Carrier density, 0210 nano-technology, Electrochemical impedance spectroscopy, lcsh:TP250-261
Abstract

The paper reports on the use of electrochemical impedance spectroscopy to determine the doping character and carrier density of freshly prepared and annealed ZnO nanostructures. The ZnO nanostructures were obtained by chemical oxidation of metallic Zn in a 5% N,N-dimethylformamide (DMF) aqueous solution at 95 °C for 24 h. The as-grown nanostructured ZnO samples display a high donor density of 3.71 ± 0.88 × 1021 cm−3. Annealing at 100 and 200 °C did not have any effect on the donor density while thermal annealing at 300 °C in air for 1 h induced a decrease in the doping concentration without affecting the surface morphology. Keywords: ZnO nanowires, Electrochemical impedance spectroscopy, Carrier density, Annealing

Published
2009
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32. Injection of charge nanostructures into insulators

Author

D. Juvé, Hans-Joachim Fitting, Matthieu Touzin, Dominique Goeuriot, Christelle Guerret-Piecourt, N. Cornet, Daniel Treheux, Univ Rostock - Physics Institut, University of Rostock, École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Centre Science des Matériaux et des Structures (SMS-ENSMSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Laboratoire de Tribologie et Dynamique des Systèmes (LTDS), École Centrale de Lyon (ECL), and Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Ecole Nationale d'Ingénieurs de Saint Etienne-Centre National de la Recherche Scientifique (CNRS)

Subjects
Secondary electron emission, Materials science, Field (physics), Charge measurements, Alumina, 02 engineering and technology, 01 natural sciences, 7. Clean energy, Secondary electrons, [SPI.MAT]Engineering Sciences [physics]/Materials, Electrical resistivity and conductivity, 0103 physical sciences, Electrical conductivity, Charge storage, General Materials Science, Charge transfer insulators, Electrical and Electronic Engineering, 010302 applied physics, Charge (physics), Insulators, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Secondary emission, Cathode ray, Atomic physics, Electric current, 0210 nano-technology
Abstract

The electron beam induced selfconsistent charge transport in insulators is described by means of an electron-hole flight–drift model FDM and an iterative computer simulation. Ballistic secondary electrons and holes, their attenuation and drift, as well as their recombination, trapping, and detrapping are included. Thermal and field-enhanced detrapping are described by the Poole–Frenkel effect. As a main result the time dependent secondary electron emission rate σ ( t ) and the spatial distributions of currents j ( x , t ) , charges σ ( x , t ) , field F ( x , t ) , and potential V ( x , t ) are obtained. The spatial charge distributions with depth show a quadropolar plus–minus–plus–minus structure in nanometer dimensions.

Published
2009
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33. Micromechanics-based modelling of stiffness and yield stress for silica/polymer nanocomposites

Author

Jean-Marc Lefebvre, M. Naït-Abdelaziz, A. Mesbah, S. Boutaleb, Taoufik Boukharouba, Jean-Michel Gloaguen, Fahmi Zaïri, Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), and Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Polymer nanocomposite, Characteristic length, Modulus, Physics::Optics, 02 engineering and technology, Micromechanical modelling, Nanocomposites, Stiffness, 0203 mechanical engineering, Materials Science(all), Modelling and Simulation, medicine, General Materials Science, Size effect, Composite material, Yield stress, Nanocomposite, Mechanical Engineering, Applied Mathematics, Stress–strain curve, Finite element analysis, Micromechanics, Silica, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Condensed Matter::Soft Condensed Matter, 020303 mechanical engineering & transports, Mechanics of Materials, Modeling and Simulation, Nanoparticles, Interphase, medicine.symptom, 0210 nano-technology, Inhomogeneous interphase
Abstract

International audience; Establishing structure–property relationships for nanoparticle/polymer composites is a fundamental task for a reliable design of such new systems. A micromechanical analytical model is proposed in the present work, in order to address the problem of stiffness and yield stress prediction in the case of nanocomposites consisting of silica nanoparticles embedded in a polymer matrix. It takes into account an interphase corresponding to a perturbed region of the polymer matrix around the nanoparticles. Its modulus is continuously graded from that of the silica nanoparticle to that of the polymer matrix. Considering the thickness of the third phase as a characteristic length scale, the influence of particle size on the overall nanocomposite behaviour is examined. The key role of the interphase on both the overall stiffness and yield stress is studied and the model output is compared to experimental data of various silica spherical nanoparticle/polymer composites extracted from the literature. The model is also used to examine the influence of interphase features on the overall nanocomposite behaviour. A finite element analysis is then achieved and the numerical results are validated using the analytical predictions. Local stress and strain distributions are analysed in order to understand the phenomena occurring at the nano-scale.

Published
2009
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34. Segmental Dynamics of Poly(ethylene oxide) Chains in a Model Polymer/Clay Intercalated Phase: Solid-State NMR Investigation

Author

Cédric Lorthioir, Françoise Lauprêtre, Jean-Marc Lefebvre, Jérémie Soulestin, Institut de Chimie et des Matériaux Paris-Est (ICMPE), Institut de Chimie du CNRS (INC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), and Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Polymers and Plastics, Oxide, 02 engineering and technology, engineering.material, 010402 general chemistry, 01 natural sciences, Inorganic Chemistry, Polymer clay, chemistry.chemical_compound, Phase (matter), Polymer chemistry, Materials Chemistry, chemistry.chemical_classification, Ethylene oxide, Organic Chemistry, Polymer, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Amorphous solid, [CHIM.POLY]Chemical Sciences/Polymers, Monomer, Chemical engineering, chemistry, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], engineering, 0210 nano-technology, Hybrid material
Abstract

International audience; A model poly(ethylene oxide) (PEO)/laponite hybrid material, characterized by a high silicate content, was used to probe the dynamical behavior of polymer chains at the surface with clay platelets. Such a system mimics the intercalated phases that may occur in polymer/clay nanocomposites with usual silicate amounts of 5 wt %. The segmental motions underlying the α-relaxation of fully amorphous PEO chains confined within the nanometer-thick laponite galleries were monitored over the tens of microseconds time scale by means of 13C and 1H solid-state NMR. A significant slowing down of these motions was mostly observed, as compared to the local dynamics in the amorphous phase of neat PEO. Strong dynamical heterogeneities among the intercalated PEO monomer units remain even at room temperature, i.e., more than 50 K above the temperature at which the frequency of the segmental motions displayed by a significant part of the PEO chain segments gets above 52 kHz. Such heterogeneities are related to a pronounced extension of the α-relaxation process toward the low-frequency side. The slowing down of the PEO segmental motions was assigned to ion-dipole interactions between the PEO oxygen atoms and the Na+ counterions located in the laponite galleries. The domains formed by PEO monomer units characterized by a reduced segmental mobility were found to display rather long lifetime, about 13 ms at room temperature.

Published
2008
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35. Predicted glide systems and crystal preferred orientations of polycrystalline silicate Mg-Perovskite at high pressure: Implications for the seismic anisotropy in the lower mantle

Author

Denise Ferré, David Mainprice, Philippe Carrez, Andréa Tommasi, Patrick Cordier, Géosciences Montpellier, Université des Antilles et de la Guyane (UAG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), and Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS)

Subjects
Seismic anisotropy, 010504 meteorology & atmospheric sciences, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, Mineralogy, 010502 geochemistry & geophysics, 01 natural sciences, Mantle (geology), Geochemistry and Petrology, crystal preferred orientation, Earth and Planetary Sciences (miscellaneous), Anisotropy, perovskite, 0105 earth and related environmental sciences, Condensed matter physics, ab initio, Isotropy, seismic anisotropy, dislocation creep, Simple shear, lower mantle, Geophysics, Shear (geology), Space and Planetary Science, Critical resolved shear stress, Peierls stress, glide systems, Geology
Abstract

International audience; We use first first-principle methods and the Peierls-Nabarro model to evaluate the resistance to glide, characterized by the Peierls stress, of glide systems for end-member MgSiO3 Perovskite at mantle pressures. [010](100) is the easiest glide system in Mg-Perovskite at all pressures. Peierls stresses increase systematically with pressure for all systems except [001](010), indicating the importance of lattice friction at lower mantle pressures. The ratio of the maximum Peierls stress for each system relative to the [010](100) value defines their critical resolved shear stress (CRSS). These CRSS are used in a visco-plastic self-consistent homogenization model to predict the evolution of crystal preferred orientations (CPO) during deformation of polycrystalline Mg-Perovskite. In axial compression, [100] tends to align with the compression direction, in agreement with in situ observations in axial compression experiments. In simple shear, [010] concentrates near the shear direction and (100), although more dispersed, tends to align near the shear plane, consistent with the dominant activity of the easier [010](100) system. The calculated seismic anisotropy for a 100% Mg-Perovskite aggregate using the CPO in simple shear and the elastic constants Of MgSiO3 perovskite at lower mantle pressures and temperatures is weak (>3% for P-waves with and >2% for S-waves) and decreases with increasing temperature and pressure. P-waves show the fastest propagation parallel to the lineation and S-waves fast polarization is in the foliation at 38 GPa and normal to the lineation at 88 GPa. This weak anisotropy is consistent with global seismological observations of a nearly isotropic lower mantle. There are however two regions where strain-induced Mg-Perovskite CPO could contribute to anisotropy; a) low temperature regions in the uppermost lower mantle, where the predicted S-wave polarization anisotropy may attain 1.6% with a fast polarization parallel to the foliation, b) in high high-temperature domains in the D '' layer, where Mg-Perovskite may be the major stable phase, leading to polarization of fast S-waves normal to the lineation for propagation directions at high angle to the lineation and an apparent isotropy for all other propagation directions.

Published
2008
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36. Evidence from numerical modelling for 3D spreading of [001] screw dislocations in Mg2SiO4forsterite

Author

Patrick Cordier, P. Carrez, Andrew Walker, Arnaud Metsue, Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences [Cambridge, UK], and University of Cambridge [UK] (CAM)

Subjects
Materials science, Mineralogy, 02 engineering and technology, Mechanics, Forsterite, engineering.material, 010502 geochemistry & geophysics, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Atomic units, Core (optical fiber), Condensed Matter::Materials Science, Planar, Physical Sciences, engineering, Density functional theory, Dislocation, 0210 nano-technology, Anisotropy, 0105 earth and related environmental sciences, Stacking fault
Abstract

International audience; Computer simulations have previously been used to derive the atomic scale properties of the cores of screw dislocations in Mg2SiO4 forsterite by direct calculation using parameterised potentials and via the Peierls-Nabarro model using density functional theory. We show that, for the [001] screw dislocation, the parameterised potentials reproduce key features of generalised stacking fault energies when compared to the density functional theory results, but that the predicted structure of the dislocation core differs between direct simulation and the Peierls-Nabarro model. The [001] screw dislocation is shown to exhibit a low-energy non-planar core. It is suggested that for this dislocation to move its core may need to change structure and form a high-energy planar structure similar to that derived from the Peierls-Nabarro model. This could lead to dislocation motion via an unlocking-locking mechanism and explain the common experimental observation of long straight screw dislocation segments in deformed olivine.

Published
2008
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37. Application of the Peierls-Nabarro model to dislocations in forsterite

Author

Julien Durinck, Philippe Carrez, Patrick Cordier, Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), and Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, 010504 meteorology & atmospheric sciences, Condensed matter physics, Stacking, Ab initio, Forsterite, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Crystallography, Geochemistry and Petrology, Atomic theory, Peierls stress, Lattice (order), [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], engineering, Partial dislocations, Dislocation, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

We present a numerical model of dislocation cores in Mg 2 SiO 4 forsterite based on the Peierls-Nabarro model and using generalised stacking faults as an input. The generalised stacking faults have been calculated from ab initio density-functional theory using VASP. Core profiles, atomic models and Peierls stresses are proposed for dislocations from the following slip systems: [100](010), [100](001), [100]{021}, [001](010), [001](100) and [001]{110}. Calculations have been performed at 0 and 10 GPa, to investigate the influence of pressure. We show that [100] dislocations have narrow cores when [001] dislocations tend to spread into (100) and {110} planes. A strong softening effect is found with pressure on the [001](010) slip system. Our study emphasizes the influence of lattice friction on plastic deformation of forsterite with, beyond Peierls stresses, possible effects related to non-planar core structures.

Published
2007
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38. Experimental and theoretical study for corrosion inhibition of mild steel in normal hydrochloric acid solution by some new macrocyclic polyether compounds

Author

Fouad Bentiss, Mounim Lebrini, Michel Traisnel, Michel Lagrenée, Hervé Vezin, Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Organique et Macromoleculaire (UMR CNRS 8009), Université de Lille, Sciences et Technologies-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), and Université Chouaib Doukkali (UCD)

Subjects
Langmuir, Materials science, Corrosion inhibitors, Constant phase element, General Chemical Engineering, Inorganic chemistry, Hydrochloric acid, General Chemistry, Polyethylene glycol, Corrosion, Dielectric spectroscopy, Mild steel, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Corrosion inhibitor, Adsorption, chemistry, HCl acid, Adsorption process, Macrocyclic compounds, General Materials Science
Abstract

New macrocyclic polyether compounds containing a 1,3,4-thiadiazole moiety have been prepared to study the corrosion inhibitive effect of mild steel in normal hydrochloric acid solutions. The salient features obtained from weight loss and electrochemical impedance spectroscopy (EIS) have been discussed. The results of these investigations have shown enhancement in inhibition efficiencies with the extent of the polyethylene glycol unit that forms a cavity. Data obtained from EIS show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE) has been used. Figure options Download full-size image Download as PowerPoint slide Adsorption of n-MCTH was found to follow the Langmuir’s adsorption isotherm. The thermodynamic functions of adsorption process were calculated from experimental ac impedance data and the interpretation of the results are given. Molecular modelling has been conducted in an attempt to correlate the corrosion inhibition properties with the calculated quantum chemical parameters.

Published
2007
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39. A transmission electron microscopy study of composition in Si1−xGex/Si (001) quantum dots

Author

Sławomir Kret, Yidir Androussi, A. Lefebvre, Vincent Ferreiro, Tarik Benabbas, Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies, Institute of Physics, Polish Academy of Sciences, and Polska Akademia Nauk = Polish Academy of Sciences (PAN)

Subjects
Materials science, Silicon, Condensed matter physics, Relaxation (NMR), chemistry.chemical_element, 02 engineering and technology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Epitaxy, 01 natural sciences, chemistry, Transmission electron microscopy, Quantum dot, Physical Sciences, 0103 physical sciences, Displacement field, Stress relaxation, 010306 general physics, 0210 nano-technology, Quantum well
Abstract

International audience; A finite-element program has been developed to model strain relaxation in the case of epitaxial Si1-xGex / Si coherent quantum dots either with or without compositional inhomogeneities. The resulting elastic displacement fields are used to calculate the intensity of dynamical plan view TEM images of such quantum dots. Various types of linear or parabolic compositional inhomogeneities are studied. TEM images of quantum dots with such inhomogeneities are calculated as well as those of quantum dots with a homogeneous composition. They are then compared with experimental images. It is shown how the analysis of the main features of these experimental images (black/white lobes and moiré-like fringes) enables us to determine the conditions in which it is possible to distinguish quantum dots with a homogeneous composition from those with compositional inhomogeneity.

Published
2007
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40. Preparation of Superhydrophobic Silicon Oxide Nanowire Surfaces

Author

Edmond Payen, Ralf Blossey, Léon Gengembre, Ahmed Addad, Yannick Coffinier, Sébastien Janel, Rabah Boukherroub, Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche Interdisciplinaire [Villeneuve d'Ascq] (IRI), Université de Lille, Sciences et Technologies-Université de Lille, Droit et Santé-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, and Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Droit et Santé-Université de Lille, Sciences et Technologies

Subjects
Amorphous silicon, Silicon, Materials science, Nanowire, chemistry.chemical_element, Nanotechnology, 02 engineering and technology, Substrate (electronics), Microscopy, Atomic Force, 010402 general chemistry, 01 natural sciences, Contact angle, chemistry.chemical_compound, Trichlorosilane, Electrochemistry, Surface roughness, General Materials Science, Composite material, Silicon oxide, Spectroscopy, silicon oxide nanowires, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Nanowires, Oxides, [CHIM.MATE]Chemical Sciences/Material chemistry, Surfaces and Interfaces, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, chemistry, Spectrophotometry, Microscopy, Electron, Scanning, chemical modification, 0210 nano-technology, Hydrophobic and Hydrophilic Interactions, superhydrophobicity
Abstract

The paper reports on the preparation of superhydrophobic amorphous silicon oxide nanowires (a-SiONWs) on silicon substrates with a contact angle greater than 150 degrees by means of surface roughness and self-assembly. Nanowires with an average mean diameter in the range 20-150 nm and 15-20 microm in length were obtained by the so-called solid-liquid-solid (SLS) technique. The porous nature and the high roughness of the resulting surfaces were confirmed by AFM imaging. The superhydrophobicity resulted from the combined effects of surface roughness and chemical modification with fluorodecyl trichlorosilane.

Published
2007
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41. Plasticity of the dense hydrous magnesium silicate phase A at subduction zones conditions

Author

Gouriet, K., Nadege Hilairet, Amiguet, E., Bolfan-Casanova, N., Wang, Y., Reynard, B., Cordier, P., Laboratoire Lasers, Plasmas et Procédés photoniques (LP3), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Unité Matériaux et Transformations - UMR 8207 (UMET), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Schlumberger, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Laboratoire de structures et propriétés de l'état solide (LSPES), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
DHMS, Physics and Astronomy (miscellaneous), Anisotropie, Dislocations, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Astronomy and Astrophysics, Glide plane, Peierls–Nabarro method, High pressure, Geophysics, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Peierls-Nabarro method, Phase A, Generalized stacking faults, Dissociation, ComputingMilieux_MISCELLANEOUS, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract

The plasticity of the dense hydrous magnesium silicate (DHMS) phase A, a key hydrous mineral within cold subduction zones, was investigated by two complementary approaches: high-pressure deformation experiments and computational methods. The deformation experiments were carried out at 11 GPa, 400 and 580 degrees C, with in situ measurements of stress, strain and lattice preferred orientations (LPO). Based on viscoplastic self-consistent modeling (VPSC) of the observed LPO, the deformation mechanisms at 580 degrees C are consistent with glide on the (00 01) basal and (01 1 0) prismatic planes. At 400 degrees C the deformation mechanisms involve glide on (211 0) prismatic, (0001) basal and {1 1 21} pyramidal planes. Both give flow stresses of 2.5-3 GPa at strain rates of 2-4 x 10(-5) s(-1\). We use the Peierls-Nabarro-Galerkin (PNG) approach, relying on first-principles calculations of generalized stacking fault (gamma-surface), and model the core structure of potential dislocations in basal and prismatic planes. The computations show multiple dissociations of the 1/3 [2 (1) over bar(1) over bar0] and [01 (1) over bar0] dislocations (< a >) and < b > dislocations) in the basal plane, which is compatible with the ubiquity of basal slip in the experiments. The gamma-surface calculations also suggest 1/3 [2 (1) over bar(1) over bar3] and [0 (1) over bar 11] dislocations (< a + c > or < c - b > directions) in prismatic and pyramidal planes, which is also consistent with the experimental data. Phase A has a higher flow strength than olivine. When forming at depths from the dehydration of weak and highly anisotropic hydrated ultramafic rocks, phase A may not maintain the mechanical softening antigorite can provide. The seismic properties calculated for moderately deformed aggregates suggest that S-wave seismic anisotropy of phase A-bearing rocks is lower than hydrous subduction zone lithologies such as serpentinites and blueschists. (C) 2015 The Authors. Published by Elsevier B.V.

Published
2015
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42. Influence of crystal chemistry on ideal plastic shear anisotropy in forsterite: First principle calculations

Author

Julien Durinck, Alexandre Legris, Patrick Cordier, Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies, Laboratoire de Métallurgie Physique et Génie des Matériaux (LMPGM), and Université de Lille, Sciences et Technologies-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-EDF (EDF)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, 010504 meteorology & atmospheric sciences, Condensed matter physics, Crystal chemistry, Slip (materials science), Forsterite, engineering.material, 01 natural sciences, Condensed Matter::Soft Condensed Matter, Pseudopotential, Crystallography, Geophysics, Shear (geology), Geochemistry and Petrology, Ab initio quantum chemistry methods, Stacking-fault energy, 0103 physical sciences, engineering, [CHIM]Chemical Sciences, 010306 general physics, Anisotropy, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

We present ab initio calculations of ideal shear strengths (ISS) in forsterite at zero temperature using pseudopotential density functional theory within the generalized gradient approximation. A localized rigid-body shear is imposed on a given plane of an infinite defect-free crystal. The energy increase associated with this shear (called the generalized stacking fault energy) gives access to the ISS. The goal of this study is to assess the influence of crystal chemistry on the intrinsic resistance of plastic shear of a mineral like forsterite. ISS have been calculated for plastic shear along [100], [010], and [001] in various potential glide planes of forsterite. We show that the [001] slip, which corresponds experimentally to an easy glide at low temperature, exhibits the lowest energy barrier. The [010] glide is precluded because it involves very unfavorable atom impingements.

Published
2005
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43. New considerations about the fracture mode of PZT ceramics

Author

Frédéric Thiebaud, J. Crampon, Christian Courtois, Olivier Guillon, Dominique Perreux, Anne Leriche, Philippe Champagne, Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Matériaux Céramiques et Procédés Associés - EA 2443 (LMCPA), Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), and Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS)

Subjects
010302 applied physics, education.field_of_study, Materials science, Population, Mineralogy, Fracture mechanics, 02 engineering and technology, 021001 nanoscience & nanotechnology, Microstructure, 01 natural sciences, Brittleness, visual_art, [SPI.MECA.MEMA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of materials [physics.class-ph], 0103 physical sciences, Materials Chemistry, Ceramics and Composites, Fracture (geology), visual_art.visual_art_medium, Grain boundary, Ceramic, Composite material, 0210 nano-technology, Porosity, education
Abstract

Sintered bulk ceramics, such as PZT are brittle materials. This macroscopically implies a statistical distribution of the ultimate strengths, because defects, such as pores or cracks are responsible for the initiation of the specimen failure. Another aspect of this fracture phenomenon is the crack propagation inside the material, along grain boundaries or through the grains themselves. An experimental study was carried out on hard and soft PZT by means of a scanning electron microscopy (SEM) quantitative analysis of tensile fractured areas. This reveals that the fracture mode is mixed, although it seems to be rather intragranular for hard ceramics and more intergranular for soft ones. Further investigations deal with the characterization of the residual porosity, which has to be distinguished from the population of critical defects. This porosity is located at grain boundaries and likely acts also as a stress concentrator and has an effect on the fracture mode and mechanical properties. For doped hard and soft PZT, a careful analysis of the microstructure is thus achieved through transmission electron microscopy (TEM) micrographs. Furthermore, domain structure is analysed for hard and soft PZT.

Published
2005
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44. Pyroxene microstructure in the Northwest Africa 856 martian meteorite

Author

Patrick Cordier, Bertrand Devouard, Hugues Leroux, François Guyot, Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)

Subjects
DIOPSIDE, 010504 meteorology & atmospheric sciences, Mineralogy, DEFORMATION MECHANISMS, Pyroxene, engineering.material, ENSTATITE, 010502 geochemistry & geophysics, 01 natural sciences, Shock metamorphism, CLINOPYROXENE, Pigeonite, COOLING-RATE, 0105 earth and related environmental sciences, Diopside, EXSOLUTION LAMELLAE, DEFECTS, X-RAY-MICROANALYSIS, Geophysics, Augite, Meteorite, Space and Planetary Science, visual_art, TRANSMISSION ELECTRON-MICROSCOPE, engineering, visual_art.visual_art_medium, Enstatite, PIGEONITE, Closure temperature, Geology
Abstract

Transmission electron microscopy was used to examine pyroxene microstructure in the Northwest Africa (NWA) 856 martian meteorite to construct its cooling and shock histories. All pyroxenes contain strained coherent pigeonite/augite exsolution lamellae on (001). The average width and periodicity of lamellae are 80 and 400 nm, respectively, indicating a cooling rate below 0.1 degreesC/hr for the parent rock. Pigeonite and augite are topotactic, with strained coherent interfaces parallel to (001). The closure temperature for Ca-Fe, Mg interdiffusion, estimated from the composition at the augite pigeonite interface, is about 700 degreesC. Tweed texture in augite reveals that a spinodal decomposition occurred. Locally, tweed evolved toward secondary pigeonite exsolutions on (001). Due to the decreasing diffusion rate with decreasing temperature, "M-shaped" concentration profiles developed in augite lamellae. Pigeonite contains antiphase boundaries resulting from the C2/c to P2(1)/c space group transition that occurred during cooling. The reconstructive phase transition from P2(1)/c clinopyroxene to orthopyroxene did not occur. The deformation (shock) history of the meteorites is revealed by the presence of dislocations and mechanical twins. Dislocations are found in glide configuration, with the [001](100) glide system preferentially activated. They exhibit strong interaction with the strained augite/pigeonite interfaces and did not propagate over large distances. Twins are found to be almost all parallel to (100) and show moderate interaction with the augite/pigeonite interfaces. These twins are responsible for the plastic deformation of the pyroxene grains. Comparison with microstructure of shocked clinopyroxene (experimentally or naturally shocked) suggests that NWA 856 pyroxenes are not strongly shocked.

Published
2004
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45. Biaxial deformation of polyamide-6: Assessment of orientation by means of infrared trichroism

Author

M. Jutigny, Patricia Krawczak, Christophe Depecker, Kenneth C. Cole, Jean-Marc Lefebvre, Institut des Matériaux Industriels, Boucherville, Canada, Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies, Université de Lille, Sciences et Technologies, Département Technologie des Polymères et Composites & Ingénierie Mécanique (TPCIM), École des Mines de Douai (Mines Douai EMD), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Ministère de l'Economie, des Finances et de l'Industrie, Institut Mines-Télécom [Paris] (IMT), and Ecole nationale supérieure Mines-Télécom Lille Douai (IMT Lille Douai)

Subjects
Materials science, Polymers and Plastics, Plane (geometry), Film plane, Infrared spectroscopy, 020206 networking & telecommunications, 02 engineering and technology, General Chemistry, 021001 nanoscience & nanotechnology, Rotation, [SPI.MAT]Engineering Sciences [physics]/Materials, [SPI]Engineering Sciences [physics], Transverse plane, Crystallography, [CHIM.POLY]Chemical Sciences/Polymers, Planar, Orientation (geometry), [SPI.MECA.MEMA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of materials [physics.class-ph], [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 0202 electrical engineering, electronic engineering, information engineering, Materials Chemistry, Composite material, Deformation (engineering), 0210 nano-technology, ComputingMilieux_MISCELLANEOUS
Abstract

Infrared spectroscopy was used to study the evolution of structure in films of polyamide-6 drawn on a Cellier tenter frame laboratory tester under conditions of simultaneous equibiaxial stretching and planar uniaxial stretching. The tilted film method was used to obtain trichroic spectra corresponding to the machine, transverse, and normal directions, as well the structural factor spectrum. From these it was possible to obtain information on the molecular orientation and the evolution of the crystalline structure. The starting films, prepared by melt casting from an extruder on a chilled roll, contained predominantly the mesomorphic β form. The structural factor spectra confirmed that strain-induced transformation into the α form occurred upon drawing, and that the amount of a form increased with the extent of drawing. The trichroic spectra showed that the molecular orientation was localized mainly, but not exclusively, in the α form. Orientation functions could be determined for both the molecular chain axis and the normal to the hydrogen-bonded sheets. For both the equibiaxial and planar uniaxial films, these sheets were found to be strongly oriented parallel to the plane of the film, with the degree of orientation increasing with overall draw ratio. For the biaxial samples, the molecular chain orientation was found to be equibiaxial, as expected. Mechanical test results indicated that the chains are evenly distributed in the film plane rather than showing a preference for the two orthogonal draw directions. For the planar uniaxial samples. the chain orientation was predominantly in the draw direction, but some degree of orientation in the transverse direction was also observed. The variation of orientation functions with draw ratio suggested that the a structure evolves in two stages, the first involving chain orientation in the draw direction and the second involving rotation of the sheets into the plane of the film.

Published
2004
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46. Magnetic Co 3 O 4 /reduced graphene oxide nanocomposite as a superior heterogeneous catalyst for one-pot oxidative esterification of aldehydes to methyl esters

Author

Amer Al-Nafiey, Suman L. Jain, Brigitte Sieber, Rabah Boukherroub, Ahmed Addad, Pascal Roussel, Vineeta Panwar, Laboratoire de structures et propriétés de l'état solide (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et de Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche Interdisciplinaire [Villeneuve d'Ascq] (IRI), Université de Lille, Sciences et Technologies-Université de Lille, Droit et Santé-Centre National de la Recherche Scientifique (CNRS), Indian Institute of Petroleum [Dehradun] (CSIR-IIP), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, and Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Droit et Santé-Université de Lille, Sciences et Technologies

Subjects
inorganic chemicals, General Chemical Engineering, Oxide, 02 engineering and technology, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, Heterogeneous catalysis, 7. Clean energy, 01 natural sciences, Catalysis, law.invention, Sodium borohydride, chemistry.chemical_compound, law, Polymer chemistry, Organic chemistry, Cobalt oxide, ComputingMilieux_MISCELLANEOUS, Nanocomposite, Graphene, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, chemistry, 0210 nano-technology, Hybrid material
Abstract

A magnetically separable hybrid material consisting of Co3O4 nanoparticles supported on reduced graphene oxide (Co3O4/rGO) was synthesized through a simple co-reduction process of graphene oxide (GO) and cobalt chloride (CoCl2) using sodium borohydride (NaBH4). The Co3O4/rGO heterogeneous catalyst exhibited a high-performance for the oxidative esterification of aldehydes to the corresponding methyl esters using tert-butyl hydroperoxide (TBHP) as an oxidant. Owing to the synergistic effect of rGO support, the hybrid catalyst exhibited superior catalytic activity to the corresponding cobalt oxide catalyst. Importantly, the synthesized hybrid possesses good magnetic properties, which enable facile recovery of the catalyst by using an external magnet.

Published
2015
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47. Water uptake, diffusion and d/h signature of amorphous silicates during hydration/dehydration and magma degassing

Author

Roskosz, M., Didier Laporte, Deloule, E., Depecker, C., Laurent Remusat, Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide (LSPES), Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC), Jouhannel, Sylvaine, Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC)

Subjects
[SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, [SDU.STU.PE] Sciences of the Universe [physics]/Earth Sciences/Petrography, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

48. The influence of hydrostatic stress states on the hydrogen solubility in martensitic steels

Author

S. Frappart, F. Thebault, J. Bouhattate, Arnaud Metsue, Laurent Delattre, S. Cohendoz, Diana Koschel, G. Courlit, D. Guedes, Jordi Creus, Patrick Girault, Abdelali Oudriss, Xavier Feaugas, Laboratoire des Sciences de l'Ingénieur pour l'Environnement - UMR 7356 (LaSIE), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), and Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Hydrogen, Mechanical Engineering, Metallurgy, Metals and Alloys, chemistry.chemical_element, Thermodynamics, Partial molar property, Condensed Matter Physics, Microstructure, Stress (mechanics), chemistry, Mechanics of Materials, Martensite, Vacancy defect, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], General Materials Science, Hydrostatic stress, Solubility, ComputingMilieux_MISCELLANEOUS
Abstract

A specific dependency of elastic tensile stress on the hydrogen solubility is identified for martensitic steels. The lattice hydrogen concentration under applied stress may be underestimated when predicted by a classical law which associates hydrostatic stress with the partial molar volume of hydrogen. We have explored the impact of elastic distortions on hydrogen solubility from two different sources: internal stresses arising from heterogeneous microstructures and elastic fields around vacancy clusters. Only the latter seems to be in reasonable agreement with our results.

Published
2014
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49. Enhanced corrosion resistance of mild steel in 1M hydrochloric acid solution by alkaloids extract from Aniba rosaeodora plant: Electrochemical, phytochemical and XPS studies

Author

Christophe Roos, Maxime Chevalier, Mounim Lebrini, Florent Robert, Michel Traisnel, Nadine Amusant, Ecologie des forêts de Guyane (UMR ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Ecologie des forêts de Guyane (ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Sciences et Technologies, Ecologie des forêts de Guyane ( ECOFOG ), Institut National de la Recherche Agronomique ( INRA ) -Université des Antilles ( UA ) -Centre de Coopération Internationale en Recherche Agronomique pour le Développement ( CIRAD ) -AgroParisTech-Université de Guyane ( UG ) -Centre National de la Recherche Scientifique ( CNRS ), School of economics and mathematics, Southwestern University of Finance and Economics [Chengdu, China], Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier ( ICGM ICMMM ), Université Montpellier 1 ( UM1 ) -Université Montpellier 2 - Sciences et Techniques ( UM2 ) -Ecole Nationale Supérieure de Chimie de Montpellier ( ENSCM ) -Université de Montpellier ( UM ) -Centre National de la Recherche Scientifique ( CNRS ), Centre de Coopération Internationale en Recherche Agronomique pour le Développement ( CIRAD ) -Institut National de la Recherche Agronomique ( INRA ) -Université des Antilles et de la Guyane ( UAG ) -AgroParisTech-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de structures et propriétés de l'état solide ( LSPES ), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique ( CNRS ), Unité de Catalyse et de Chimie du Solide - UMR 8181 ( UCCS ), Université d'Artois ( UA ) -Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille ( ENSCL ) -Université de Lille-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de structures et propriétés de l'état solide (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), and Université des Antilles (UA)-Université de Guyane (UG)-Centre National de la Recherche Scientifique (CNRS)-AgroParisTech-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)

Subjects
K50 - Technologie des produits forestiers, Aniba rosaeodora, General Chemical Engineering, 02 engineering and technology, 01 natural sciences, chemistry.chemical_compound, Electrochemistry, Acier, Polarization (electrochemistry), ComputingMilieux_MISCELLANEOUS, Inhibition, biology, Composition chimique, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Dielectric spectroscopy, Corrosion, Extrait d'origine végétale, visual_art, Huile essentielle, visual_art.visual_art_medium, 0210 nano-technology, F60 - Physiologie et biochimie végétale, Inorganic chemistry, Hydrochloric acid, 010402 general chemistry, Metal, Corrosion inhibitor, Alcaloïde, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Acidité, Propriété physicochimique, Constant phase element, Extrait de bois, biology.organism_classification, 0104 chemical sciences, chemistry, [ CHIM.MATE ] Chemical Sciences/Material chemistry, Adsorption
Abstract

The present report continues to focus on the broadening application of plant extracts for metallic corrosion control and reports on the inhibiting effect of the Aniba rosaeodora alkaloidic extract on the corrosion of C38 steel in 1 M hydrochloric acid. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were applied to study the metal corrosion behavior in the absence and presence of inhibitor. Studies on the phytochemical constituents were established to determine the active(s) molecule(s). XPS was also carried out to establish the mechanism of corrosion inhibition of the active molecule of C38 steel in acid solution. The inhibitor extract acted as an efficient corrosion inhibitor in 1 M HCl. The experimental data obtained from EIS method show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPEα, Q) has been used. Graphical methods are illustrated by synthetic data to determine the parameter of CPE (α, Q). Polarization studies showed that the Aniba rosaeodora alkaloidic extract was a mixed-type inhibitor and its inhibition efficiency increased with the inhibitor concentration. Studies on the phytochemical constituents of the total alkaloids extract shows that it contains the anibine as the major alkaloid. The results obtained from the electrochemical study have clearly showed that the inhibition efficiency of the total extract was due to the presence of anibine. The XPS studies showed the formation of inhibitor layer containing the Aniba rosaeodora alkaloidic extract and the anibine molecules.

Published
2014
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50. Deformation mechanisms and rheology of serpentines in experiments and in nature

Author

Amiguet, Elodie, Van De Moortèle, Bertrand, Cordier, Patrick, Hilairet, Nadège, Reynard, Bruno, Laboratoire de structures et propriétés de l'état solide - UMR 8008 (LSPES), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Sciences de la Terre (LST), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de structures et propriétés de l'état solide (LSPES), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)

Subjects
[SDU]Sciences of the Universe [physics], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract

International audience; Microstructures in serpentine samples recovered from deformation experiments performed at high pressure (1-8 GPa), high temperature (150-500 degrees C), and laboratory strain rates (4 10(-4)-10(-6)s(-1)) were studied using transmission electron microscopy on thin sections prepared by focused ion beam. Lizardite crystals deform by easy glide along the basal planes associated with microkink. This mechanism is associated with a plastic strength of similar to 100MPa that defines the upper bound of lizardite strength in natural conditions. Antigorite crystals deform essentially by conjugated slip along (101) and (10 (1) over bar) planes observed in sections close to (010). This conjugate system results in an apparent global slip system akin to [100](001). In all samples, delamination and comminution produce fine-grained interconnected regions at grain boundaries because intracrystalline deformation mechanisms are insufficient to satisfy the von Mises criterion. The deformation laws of lizardite (plastic flow) and antigorite (strain rate dependent) differ because of their differing intracrystalline deformation mechanisms. Subgrain boundary geometry in natural samples and [100](001) crystal preferred orientations indicate the activation of slip systems similar to those observed in experimentally deformed samples, suggesting that the strain rate-dependent rheology of antigorite derived from experiments applies to subduction zone conditions. Delamination of antigorite crystals of a few tens to hundreds of nanometers is not observed in natural samples from subduction zones, suggesting plastic deformation of serpentinites at natural low strain rates and stresses is likely accompanied by recrystallization through dissolution-precipitation processes that act as a low-temperature equivalent of dynamic recrystallization through diffusion at high temperature.

Published
2014
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