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1,157 results

201. Theoretical and experimental investigation on the intersystem crossing kinetics in benzothioxanthene imide luminophores, and their dependence on substituent effects

Author: Marqués, Pablo Simón, Andrés Castán, José María, Josse, Pierre, Blais, Martin, Habibi, Amir Hossein, Ramírez, Iván, Walzer, Karsten, Roncali, Jean, Blanchard, Philippe, Cabanetos, Clément, Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), MOLTECH-Anjou, Université d'Angers (UA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and ANR-16-CE07-0015,SADAM,Diagnostiquer et guérir par des agents azamacrocycliques multimodaux(2016)
Subjects: Materials science, 010405 organic chemistry, Substituent, General Physics and Astronomy, Quantum yield, Chromophore, Electroluminescence, 010402 general chemistry, Photochemistry, 01 natural sciences, 0104 chemical sciences, 3. Good health, chemistry.chemical_compound, Intersystem crossing, chemistry, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, Luminescence, Imide, Perylene
Abstract: In spite of their remarkable luminescence properties, benzothioxanthene imide (BTXI an imide containing rylene chromophores) derivatives have been largely overlooked compared to their perylene bisimide and naphthalene bisimide counterparts. Thus their detailed photophysics are much less understood. In this paper, we show how relatively simple structural modifications of the backbone of BTXIs can lead to impressive variations in their Inter-System Crossing kinetics. Thus, through rational engineering of their structure, it is possible to obtain a triplet formation quantum yield that reaches unity, making BTXI a promising class of compounds for triplet-based applications (photodynamic therapy, electroluminescence, etc.).
Published: 2020
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202. Diphenylsilane‐Manganese Acetylacetonate Redox Initiating Systems: Toward Amine‐Free and Peroxide‐Free Systems

Author: Cassia Boyadjian, Ahmad Arar, Jean-Pierre Fouassier, Patxi Garra, Jacques Lalevée, Assi Al Mousawi, Institut de Science des Matériaux de Mulhouse (IS2M), Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)
Subjects: mild conditions, Polymers and Plastics, Organic Chemistry, 02 engineering and technology, redox polymerization, 010402 general chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Peroxide, Redox, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Manganese acetylacetonate, Polymer chemistry, Materials Chemistry, Amine gas treating, Physical and Theoretical Chemistry, 0210 nano-technology, [CHIM.OTHE]Chemical Sciences/Other, peroxide-free systems
Abstract: International audience; Room temperature redox initiated free radical polymerization (RFRP), without light, brings a significant breakthrough in the field of materials science including energy conservation, high efficiency, robustness in thick materials/composites, and easy operation. Meanwhile, the current redox initiating systems used are based on toxic aromatic amines and hazardous peroxides (e.g., dibenzoylperoxide). In the present paper, for the first time in literature, new amine-free, peroxide-free redox two component (2K) initiating systems comprised of diphenylsilane (DPS, a reducing agent) and manganese acetylacetonate (Mn(acac)3, an oxidizing agent) are proposed. The significance of the system is its applicability under mild conditions (RT, under air). Optical pyrometry measurement results showed that the DPS in combination with Mn(acac)3 exhibited an excellent radical initiating property for benchmark (meth)acrylate monomers, competitive with a well-established amine/dibenzoyl peroxide reference. Based on electron spin resonance experiments, the initiating chemical mechanisms of RFRP are proposed.
Published: 2020
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203. A new strategy for the synthesis of monomethylhydrazine using the Raschig process. 2: Continuous synthesis of stoichiometric monochloramine using the microreactor technology

Author: V. Pasquet, A. J. Bougrine, D. M. Le, Henri Delalu, O. Duclos, Laboratoire Hydrazines et Composés Energetiques Polyazotés (LHCEP), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-HERAKLES - SAFRAN-Centre National d'Études Spatiales [Toulouse] (CNES)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Chloramine, Materials science, 010405 organic chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Monomethylhydrazine, chemistry.chemical_compound, chemistry, Chemical engineering, Sodium hydroxide, Yield (chemistry), Reagent, [CHIM]Chemical Sciences, Raschig process, Physical and Theoretical Chemistry, Microreactor, ComputingMilieux_MISCELLANEOUS
Abstract: After having established in a previous paper that the synthesis of stoichiometric monochloramine is hazardous due to the high exothermicity of the reaction and the risk of decomposition of the solution from 36 °C, it appeared that the best solution for this synthesis is to use microreactor technology. A series of experiments carried out using a Doehlert experimental design provided access to a mathematical model describing, for an initial fixed composition ratio [NH4+]0/[OCl−]0, the evolution of the yield as a function of temperature, the flow rate of the reagents and the number of sodium hydroxide equivalent. Thus, the optimal conditions for the synthesis of stoichiometric chloramine using microreactor technology were established.
Published: 2020
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204. Light and chemical oscillations: Review and perspectives

Author: Pier Luigi Gentili, Jean-Claude Micheau, Interactions moléculaires et réactivité chimique et photochimique (IMRCP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Fluides, Energie, Réacteurs, Matériaux et Transferts (FERMAT), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), IDeAS - Interfaces Dynamiques et Assemblages Stimulables (IDeAS), and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT)
Subjects: Physics, Organic Chemistry, Chemical oscillations, Chemical waves, Circadian rhythms, Neuromorphic engineering, Photochromism, Turing patterns, Soft robotics, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Signal, Catalysis, 0104 chemical sciences, Dissipative system, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS
Abstract: When UV–vis radiation interacts with matter, it can play as either a pump, or a developer, or a signal. In this paper, we show that when UV–vis radiation interacts with very-far-from-equilibrium systems, it can exert its threefold role. It can originate oscillations when it works as a pump. It can track the hydrodynamics of fluids by inducing fluorescence or colour formation of specific probes when it works as a developer. Finally, it can affect spontaneous chemical oscillations, chemical waves, Turing patterns, and promote synchronization phenomena when it works as a signal. A cross-disciplinary analysis of many experiments shows that the interplay between UV–vis radiation and very-far-from-equilibrium systems has promising technological applications. Such interaction can be exploited to control the morphology of materials, implement chemical systems for computing, and promote soft robotics. Since dissipative chemical systems exhibit life-like functionalities, this work can be inspirational for those researchers engaged in the study of the origin of life where spontaneous phenomena of self-organization induced by light are relevant.
Published: 2020
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205. Surface and Electronic Features of Fluorinated TiO 2 and Their Influence on the Photocatalytic Degradation of 1-Methylnaphthalene

Author: Leonardo Palmisano, Frederic Dappozze, Gilles Ledoux, Chantal Guillard, Mohamed Faouzi Nsib, Yves Chevalier, Luis Cardenas, David Amans, Nidhal Fessi, Ammar Houas, Francesco Parrino, Laboratoire d'automatique, de génie des procédés et de génie pharmaceutique (LAGEPP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Supérieure Chimie Physique Électronique de Lyon-Centre National de la Recherche Scientifique (CNRS), Unité de Recherche Catalyse et Matériaux pour l’Environnement et les Procédés URCMEP (UR11ES85), Faculté des Sciences de Gabès/Université de Gabès, Campus Universitaire Cité Erriadh, Gabès 6072, Tunisia, Université de Sousse, Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), IRCELYON-Catalyse Hétérogène pour la Transition Energétique (CATREN), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Centre for Atmospheric Research Experiments (CARE), Environment and Climate Change Canada, IRCELYON-Catalytic and Atmospheric Reactivity for the Environment (CARE), Department of Industrial Engineering, University of Trento, via Sommarive 9, 38123 Trento, Italy, Università degli studi di Palermo - University of Palermo, Luminescence (LUMINESCENCE), Institut Lumière Matière [Villeurbanne] (ILM), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon
Subjects: Anions, Materials science, Halogenation, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, 1-Methylnaphthalene, chemistry.chemical_compound, Degradation, Physical and Theoretical Chemistry, Photocatalytic degradation, Oxides, Fluorine, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, General Energy, [CHIM.POLY]Chemical Sciences/Polymers, [SDV.SP.PG]Life Sciences [q-bio]/Pharmaceutical sciences/Galenic pharmacology, Chemical engineering, chemistry, 13. Climate action, Photocatalysis, 0210 nano-technology
Abstract: International audience; Surface fluorination improves the photocatalytic activity of TiO2, and the influences of various features of fluorinated TiO2 (TiO2–F) have often been discussed in the literature. The present paper addresses the changes induced by surface fluorination on the morphological, structural, surface, and electronic features of TiO2. In particular, X-ray diffraction, specific surface area analysis, and transmission and scanning electron microscopy give evidence that surface fluorination does not affect the structural properties and the morphology of TiO2 nanoparticles. In contrast, fluorination induces changes of surface and electronic properties. Chemical and thermogravimetric analyses show that surface fluorination can reach up to 50% of original Ti–OH surface sites. The surface charge of TiO2 turns more negative upon fluorination, as shown by a shift of the point of zero charge toward lower pH. Electronic properties are deeply characterized by combining diffuse reflectance, X-ray, and UV photoelectron spectroscopies, as well as time-resolved fluorescence spectroscopy, and photoelectrochemical measurements. Results show the presence of intra-band-gap energy states induced by the local interaction of chemisorbed fluorine atoms. Such energy levels are close to the valence band. The unique surface and electronic properties of TiO2–F make it a promising material for the photocatalytic degradation of poorly soluble emerging pollutants such as 1-methylnaphtalene. In particular, TiO2–F demonstrates faster degradation kinetics with respect to both the pristine material and TiO2 P25 used as a benchmark standard.
Published: 2020
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206. Modeling interfacial electrochemistry: concepts and tools

Author: Arthur Hagopian, Jean-Sébastien Filhol, Anja Kopač Lautar, University of Ljubljana, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)
Subjects: Double layer (biology), Materials science, Standard hydrogen electrode, Ab initio, General Physics and Astronomy, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, symbols.namesake, Chemical physics, Helmholtz free energy, Density of states, symbols, [CHIM]Chemical Sciences, Reactivity (chemistry), Density functional theory, Physics::Chemical Physics, Physical and Theoretical Chemistry, 0210 nano-technology, Fukui function, ComputingMilieux_MISCELLANEOUS
Abstract: This paper presents a grand canonical formalism to treat electrochemical effects at interfaces. This general formalism is linked with the classical chemical hydrogen electrode (CHE) approximation and an improved approximation is proposed. This new approximation including a higher order correction that (i) keeps the low computational cost of classical CHE approach, (ii) does not require to know the type of reaction (electrochemical/not electrochemical) and (iii) should give better estimates in many problematic cases. Beyond the applicability domain of this new approximation, the homogeneous background method (HBM) which is a potential dependent density functional theory method is then presented. HBM allows computing and extracting, at ab initio level, electrochemical properties of molecules either adsorbed or in the double layer. In particular, quantitative redox potential and number of exchanged electrons can be computed giving access to non-integer electron exchange or decoupled electron/proton transfer reactions. Tools for rationalizing electrochemical reactivity consisting of potential dependant projected density of states, Fukui function and metallicity index are defined. The methodology and tools are applied to examples relevant to the energy domain in order the compare reactivity in the outer Helmholtz plane and at the surface. Then, the combination of HBM and reactivity create a toolbox usable to predict and investigate the different redox, degradation and ageing processes occurring at an electrochemical interface such as the one found in energy materials but also in all electrochemical applications.
Published: 2020
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207. Molecular Selectivity of CO–N 2 Mixed Hydrates: Raman Spectroscopy and GCMC Studies

Author: Jean-Marc Simon, Antoine Patt, J. M. Salazar, Claire Petuya, Sylvain Picaud, Arnaud Desmedt, Laboratoire d'astrophysique de l'observatoire de Besançon (UMR 6091) (LAOB), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Electrical Engineering Department, Universitat Politècnica de Catalunya [Barcelona] (UPC), Institut des Sciences Moléculaires (ISM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Centre National de la Recherche Scientifique (CNRS), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire Interdisciplinaire Carnot de Bourgogne [Dijon] (LICB), and Université de Bourgogne (UB)-Université de Technologie de Belfort-Montbeliard (UTBM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, symbols.namesake, General Energy, [SDU]Sciences of the Universe [physics], symbols, [CHIM]Chemical Sciences, Physical chemistry, Physical and Theoretical Chemistry, 0210 nano-technology, Selectivity, Raman spectroscopy, Raman scattering, ComputingMilieux_MISCELLANEOUS
Abstract: This paper reports a novel quantitative investigation concerning the CO selectivity properties for mixed CO–N2 hydrates. The study was developed by combining Raman scattering experiments and grand ...
Published: 2020
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208. Noble Gas Reactivity in Planetary Interiors

Author: Chrystele Sanloup, Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), and Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Materials Science (miscellaneous), planetary interiors, Biophysics, General Physics and Astronomy, chemistry.chemical_element, helium, 01 natural sciences, Astrobiology, Neon, Xenon, 0103 physical sciences, neon, Physical and Theoretical Chemistry, 010306 general physics, Mathematical Physics, Helium, krypton, Argon, Krypton, Noble gas, lcsh:QC1-999, xenon, Helium compounds, high pressure, Planetary science, chemistry, 13. Climate action, argon, lcsh:Physics, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: International audience; While the field of noble gas reactivity essentially belongs to chemistry, Earth and planetary sciences have brought a different perspective to the field. Indeed, planetary interiors are natural high pressure (P) and high temperature (T) laboratories, where conditions exist where bonding of the heaviest noble gases may be induced thermodynamically through volume reduction (Le Châtelier's principle). Earth and planetary sciences besides generate numerous and precise observations such as the depletion of the terrestrial and martian atmospheres in xenon, pointing to the potential for Xe to be sequestered at depth, potentially induced by its reactivity. More generally, this paper will review the advances on noble gas reactivity at the extreme P-T conditions found within planetary interiors from experiments and theoretical investigations. This review will cover the synthesis of cage compounds, stoichiometric oxides and metals, and non-stoichiometric compounds where noble gases are only minor or trace elements but could be essential in solving some Earth and planetary puzzles. An apparent trend in noble gas reactivity with P emerges. In the case of Xe which is the most documented, metals are synthesized above 150 GPa, i.e., at terrestrial core conditions, stoichiometric Xe-oxides between 50 and 100 GPa, i.e., in the P-T range of the Earth's lower mantle, but Xe-O high energy bonds may also form under the modest pressures of the Earth's crust (
Published: 2020
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209. A review on potentials of coupling PCM storage modules to heat pipes and heat pumps

Author: Saman Rashidi, Souad Harmand, Hamid Shamsabadi, Javad Abolfazli Esfahani, Semnan University, Ferdowsi University of Mashhad, Mashhad, Iran, Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines - UMR 8201 (LAMIH), and INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France)-Centre National de la Recherche Scientifique (CNRS)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)
Subjects: Thermal efficiency, Materials science, business.industry, Thermal resistance, 02 engineering and technology, [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph], 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, 7. Clean energy, Phase-change material, 010406 physical chemistry, 0104 chemical sciences, law.invention, Heat pipe, Thermal conductivity, law, Heat transfer, Physical and Theoretical Chemistry, 0210 nano-technology, business, Process engineering, Thermal energy, Heat pump
Abstract: International audience; A large portion of world’s final energy consumption is employed in thermal form. The proper techniques can be used to improve the efficiencies of thermal energy systems and decrease the energy consumption. Phase change material (PCM) storage modules can be coupled with different thermal systems to improve their thermal efficiency. This paper reviews the real potentials of coupling PCM storage modules to heat pipes and heat pumps in terms of energy saving and thermal energy management. The different systems suggested by researchers are described, and the main findings of the studies are provided. The advantages and disadvantages of these combined systems are discussed, and some suggestions for future studies are provided. The results show that heat pipes show great heat transfer ability and have good efficiency in improving heat transfer within PCMs. Moreover, heat pipes can be incorporated into PCMs to decrease the thermal resistance. The purpose of PCM coupled with heat pipe is to incorporate the large thermal conductivity of heat pipe with the large latent heat capacity of PCM. PCMs have ability to balance the unconformity between supply and demand in heat pumps and decrease the size of storage tank used in a heat pump module.
Published: 2020
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210. Thermal control of electronic components using a liquid around the phase change material

Author: Haythem Shili, Kamel Fahem, Souad Harmand, Sadok Ben Jabrallah, Faculté des Sciences de Bizerte [Université de Carthage], Université de Carthage - University of Carthage, Laboratoire d’Énergétique et des Transferts Thermiques et Massiques [Tunis] (LETTM), Faculté des Sciences Mathématiques, Physiques et Naturelles de Tunis (FST), Université de Tunis El Manar (UTM)-Université de Tunis El Manar (UTM), Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines - UMR 8201 (LAMIH), and Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Centre National de la Recherche Scientifique (CNRS)-INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France)
Subjects: Convection, Materials science, 02 engineering and technology, [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph], 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Phase-change material, Heat capacity, 010406 physical chemistry, 0104 chemical sciences, Thermal conductivity, visual_art, Electronic component, Heat transfer, Thermal, visual_art.visual_art_medium, Physical and Theoretical Chemistry, Composite material, 0210 nano-technology, Overheating (electricity)
Abstract: International audience; As part of the research in the field of thermal control of electronic components, we confined a phase change material (plastic paraffin) in a liquid and we heated it on one vertical side by a hot plate. The presence of the liquid around the phase change material (PCM) prevents the direct contact between the hot plate and the PCM (increases the lifetime of the PCM by reducing overheating zones). It improves heat transfer by increasing the thermal conductivity around the PCM (increases the thermal exchange surface) and by accelerating the convective transfer (it starts very quickly without waiting for the beginning of melting). In this work, we examine experimentally and numerically the effect of the choice of liquid on the PCM and on the heating plate. In this paper, water and Siloil M40.165/200.10 are employed around the phase change materials and a comparative study of some important results examining the melt front, total melting time, flow direction and thermal behavior is conducted to investigate which liquid is the most optimal to use. Finally, it has been found that the thermal properties of water (especially heat capacity) seem to be the most interesting for a thermal protection role.
Published: 2020
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211. A rapid method for analyzing the chemical bond from energy densities calculations at the bond critical point

Author: Pascal Boulet, Marie-Christine Record, Hailong Yang, Matériaux divisés, interfaces, réactivité, électrochimie (MADIREL), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU), and Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)
Subjects: Electron density, 010304 chemical physics, Chemistry, Atoms in molecules, Charge density, electron density topological properties, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, Condensed Matter Physics, 01 natural sciences, Biochemistry, Molecular physics, DFT, Critical point (mathematics), 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Chemical bond, QTAIM, Polarizability, 0103 physical sciences, Molecule, Physical and Theoretical Chemistry, Laplace operator, ComputingMilieux_MISCELLANEOUS
Abstract: International audience; The quantum theory atoms in molecules (QTAIM) method has been used in this paper to characterize various bonding interactions in molecules and solid compounds. By using DFT-PAW calculations, complete electron density Laplacian distributions have been obtained and related to energies densities calculated at the bond critical points. From the analysis of these results a simple and rapid method, based solely on local energies densities calculations, is proposed to diagnose the bonding state, the polarizability and the deformation of the charge distribution
Published: 2020
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212. A collocation-based multi-configuration time-dependent Hartree method using mode combination and improved relaxation

Author: Wodraszka, Robert, Carrington, Tucker Jr, Department of Chemistry, Queen's University Kingston, and Queen's University [Kingston, Canada]
Subjects: [PHYS]Physics [physics], Collocation, 010304 chemical physics, Basis (linear algebra), Multi-configuration time-dependent Hartree, General Physics and Astronomy, Basis function, Hartree, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, 0103 physical sciences, Applied mathematics, [CHIM]Chemical Sciences, Relaxation (approximation), Physics::Chemical Physics, Physical and Theoretical Chemistry, Eigenvalues and eigenvectors, ComputingMilieux_MISCELLANEOUS, Interpolation, Mathematics
Abstract: Although very useful, the original multi-configuration time-dependent Hartree (MCTDH) method has two weaknesses: (1) its cost scales exponentially with the number of atoms in the system; (2) the standard MCTDH implementation requires that the PES be in sum-of-product (SOP) form in order to reduce the cost of computing integrals in the MCTDH basis. One way to deal with (1) is to lump coordinates into groups. This is called mode combination (MC). One way to deal with (2) is to reformulate MCTDH using collocation so that there are no integrals. In this paper we combine MC and collocation to formulate a mode combination collocation multiconfiguration time-dependent Hartree method (MC-C-MCTDH). In practice, its cost does not scale exponentially with the number of atoms in the system and it can be easily used with any general potential energy surfaces (PES); the PES need not be a SOP and need not have a special form. No integrals and hence no quadratures are necessary. We demonstrate the accuracy and e ciency of the new method by computing vibrational energy eigenstates of the methyl radical, methane, and acetonitrile. To do this, we use MC-C-MCTDH with a variant of improved relaxation, derived by evaluating a residual at points rather than starting from a variational principle. Because the MC basis functions are multivariate, collocation points in multidimensional spaces are required. We use two types of collocation points: 1) DVR (discrete variable representation)-like points obtained from (approximate) simultaneous diagonalisation of matrices; and 2) Leja points, which are known to be good interpolation points, determined from a generalised recipe suitable for any (not necessarily polynomial-type) basis.
Published: 2020
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213. Keto‐coumarin scaffold for photoinitiators for 3D printing and photocomposites

Author: Giacomo Rodeghiero, Akram Hijazi, Mira Abdallah, Jacques Lalevée, Andrea Gualandi, Frédéric Dumur, Pier Giorgio Cozzi, Institut de Science des Matériaux de Mulhouse (IS2M), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Dipartimento di Chimica 'G. Ciamician', Alma Mater Studiorum, Università di Bologna, Bologna, Italy, Abdallah M., Dumur F., Hijazi A., Rodeghiero G., Gualandi A., Cozzi P.G., Lalevee J., and Dumur, Frederic
Subjects: Scaffold, Materials science, Polymers and Plastics, 3D printing, 02 engineering and technology, 010402 general chemistry, Photochemistry, 01 natural sciences, law.invention, chemistry.chemical_compound, law, Materials Chemistry, Physical and Theoretical Chemistry, [CHIM.MATE] Chemical Sciences/Material chemistry, 3D printing resin, business.industry, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Coumarin, 0104 chemical sciences, Photopolymer, chemistry, photopolymerization, light-emitting diode, photocomposite, photoinitiator, keto-coumarin, 0210 nano-technology, business, Photoinitiator, Light-emitting diode
Abstract: The purposes of this paper are moving toward (a) the development of a new series of photoinitiators (PIs) which are based on the keto-coumarin (KC) core, (b) the introduction of light-emitting diodes (LEDs) as inexpensive and safe sources of irradiation, (c) the study of the photochemical mechanisms through which the new PIs react using different techniques such as Fourier transform infrared, UV–visible or fluorescence spectroscopy, and so on, (d) the use of such compounds (presenting good reactivity and excellent photopolymerization initiating abilities) for two specific and high added value applications: 3D printing (@405 nm) and preparation of thick glass fiber photocomposites with excellent depth of cure, and finally (e) the comparison of the performance of these KC derivatives versus other synthesized coumarin derivatives. In this study, six well-designed KC derivatives (KC-C, KC-D, KC-E, KC-F, KC-G, and KC-H) are examined as high-performance visible-light PIs for the cationic polymerization of epoxides as well as the free-radical polymerization of acrylates upon irradiation with LED@405 nm. Excellent polymerization rates are obtained using two different approaches: a photo-oxidation process in combination with an iodonium (Iod) salt and a photo-reduction process when associated with an amine (N-phenylglycine or ethyl 4-(dimethylamino)benzoate). High final reactive conversions were obtained. A full picture of the involved photochemical mechanisms is provided.
Published: 2020
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214. Inverted Vibrational and Rotational Excitation of CN(B 2 Σ + ) Produced through Superexcited Ion-Pair States of MCN (M = Na, K, Rb)

Author: Gwang-Hi Jeung, Hisato Yasumatsu, Institut des Sciences Moléculaires de Marseille (ISM2), and Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010304 chemical physics, Cyanide, Ion pairs, 010402 general chemistry, Alkali metal, 01 natural sciences, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, chemistry, 0103 physical sciences, Physical chemistry, Molecule, Physical and Theoretical Chemistry, Excitation, ComputingMilieux_MISCELLANEOUS
Abstract: This paper reports an energy-partition mechanism in dissociative excitation of alkali cyanide molecules, MCN (M = Rb, K, Na), to produce CN(B2Σ+) and M(ns2S) (n = 5, 4, and 3 for Rb, K, and Na, res...
Published: 2020
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215. Estimation of pore pressure and phase transitions of water confined in nanopores with non-local density functional theory

Author: Christelle Miqueu, David Grégoire, Laboratoire des Fluides Complexes et leurs Réservoirs (LFCR), Centre National de la Recherche Scientifique (CNRS)-Université de Pau et des Pays de l'Adour (UPPA)-TOTAL FINA ELF, Institut Universitaire de France (IUF), and Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.)
Subjects: Phase transition, Materials science, 010304 chemical physics, Biophysics, nanopores, SAFT-VR, [SPI.MECA.MSMECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Materials and structures in mechanics [physics.class-ph], [PHYS.MECA.MSMECA]Physics [physics]/Mechanics [physics]/Materials and structures in mechanics [physics.class-ph], 010402 general chemistry, Condensed Matter Physics, Non local, 01 natural sciences, 0104 chemical sciences, phase transitions, Nanopore, Pore water pressure, Adsorption, Chemical physics, adsorption, 0103 physical sciences, Density functional theory, Physical and Theoretical Chemistry, Molecular Biology
Abstract: International audience; In this paper, the non-local density functional theory is used in combination with SAFT-VR, to investigate the pore pressure behaviour of water confined in various nanopores. Due to the efficiency and low computational cost of the method, many configurations and thermodynamic conditions are explored. In particular, capillary condensation and evaporation of water, their impact on the pore pressure, and the effect of surface activation are evaluated. Successive first-order phase transitions of ultra-confined water monolayer are also highlighted.
Published: 2020
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216. High Order ADER Schemes for Continuum Mechanics

Author: Elena, Gaburro, Busto, Saray, Chiocchetti, Simone, Dumbser, Michael, Gaburro, Elena, Peshkov, Ilya, and University of Trento [Trento]
Subjects: Computer science, Materials Science (miscellaneous), Biophysics, FOS: Physical sciences, General Physics and Astronomy, Context (language use), 01 natural sciences, law.invention, Mathematics::Numerical Analysis, symbols.namesake, Discontinuous Galerkin method, law, 0103 physical sciences, FOS: Mathematics, Applied mathematics, Polygon mesh, Cartesian coordinate system, Mathematics - Numerical Analysis, Physical and Theoretical Chemistry, [MATH]Mathematics [math], 010306 general physics, Mathematical Physics, ComputingMilieux_MISCELLANEOUS, Physics::Computational Physics, Finite volume method, Continuum mechanics, diffuse interface, high order, Eulerian path, Numerical Analysis (math.NA), Computational Physics (physics.comp-ph), lcsh:QC1-999, Solid mechanics, symbols, Godunov-Peshkov-Romenski model, finite volume, Physics - Computational Physics, lcsh:Physics, discontinuous Galerkin
Abstract: In this paper we first review the development of high order ADER finite volume and ADER discontinuous Galerkin schemes on fixed and moving meshes, since their introduction in 1999 by Toro et al. We show the modern variant of ADER based on a space-time predictor-corrector formulation in the context of ADER discontinuous Galerkin schemes with a posteriori subcell finite volume limiter on fixed and moving grids, as well as on space-time adaptive Cartesian AMR meshes. We then present and discuss the unified symmetric hyperbolic and thermodynamically compatible (SHTC) formulation of continuum mechanics developed by Godunov, Peshkov, and Romenski (GPR model), which allows to describe fluid and solid mechanics in one single and unified first order hyperbolic system. In order to deal with free surface and moving boundary problems, a simple diffuse interface approach is employed, which is compatible with Eulerian schemes on fixed grids as well as direct Arbitrary-Lagrangian-Eulerian methods on moving meshes. We show some examples of moving boundary problems in fluid and solid mechanics.
Published: 2020
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217. Local order and cluster formation in model fluids with competing interactions: a simulation and theoretical study

Author: Jean-Louis Bretonnet, Dino Costa, Jean-Marc Bomont, Laboratoire de Chimie et Physique - Approche Multi-échelle des Milieux Complexes (LCP-A2MC), Université de Lorraine (UL), Dipartimento di Fisica e Scienze della Terra [Messina], and Universita degli Studi di Messina
Subjects: Physics, [PHYS]Physics [physics], 010304 chemical physics, Oscillation, Monte Carlo method, Shell (structure), General Physics and Astronomy, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Order (biology), 0103 physical sciences, Cluster (physics), [CHIM]Chemical Sciences, Model fluids with microscopic competing interactions, clustering in fluids, Monte Carlo simulations, hypernetted chain integral equation theory of the fluid phase, Statistical physics, Physical and Theoretical Chemistry, 0210 nano-technology, Structure factor, Cluster analysis, Phenomenology (particle physics)
Abstract: International audience; In a preliminary study [Phys. Chem. Chem. Phys., 2017, 19, 15247], we have recently documented an elusive mechanism underlying the cluster formation in model fluids with microscopic competing interactions (hard-sphere two-Yukawa). This mechanism consists in a tiny rearrangement of a distant correlation peak in the local density profile. For weak attractions, this peak contributes to the shallow, long-wave oscillation typical of such fluids; as the attraction strengthens, such a portion progressively disengages from the long-range behaviour, and moving backwards takes on the character of a new shell of neighbours, falling beyond the existing ones at shorter distances. This “reversal of trend” – despite its tiny size, in comparison with the overall aspect of the density profile – is shown to precisely occur at the onset of clustering. The scope of the present study is twofold. In the first instance, we positively assess our preliminary finding. To this aim we have studied by Monte Carlo simulations different families of two-Yukawa fluids, under the same conditions investigated in the original paper, namely fixed temperature, high fluid-density and increasingly attractive strength. Apparently, the reversal of trend in spatial correlations sets as a sensitive criterion to identify the clustering threshold, complementing other common indicators, based on the modifications undergone by the low-wavevector peak in the structure factor. Secondly, we document the accuracy of the Hypernetted Chain theory in predicting the spatial rearrangement under scrutiny. This evidence paves the way to an extended investigation of the observed phenomenology by the complementary use of theoretical and simulation tools.
Published: 2020
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218. Conceptual density functional theory: status, prospects, issues

Author: Paul Geerlings, Christophe Morell, Alejandro Toro-Labbé, Eduardo Chamorro, Shubin Liu, Pratim Kumar Chattaraj, Frank De Proft, Alberto Vela, Paul W. Ayers, José L. Gázquez, Res Grp Gen Chem, Vrije Universiteit Brussel (VUB), Universidad Andres Bello - Department of Chemistry, Department of Chemistry and Center for Theoretical Studies - Indian Institute of Technology, Eenheid Algemene Chemie, Departemento de Quίmica [Ciudad de Mexico], Universidad Autonoma Metropolitana, Unidad Iztapalapa (UAM), University of North Carolina at Chapel Hill, University of North Carolina [Chapel Hill] (UNC), University of North Carolina System (UNC)-University of North Carolina System (UNC), Chemometrics and Theoretical Chemistry - Chimiométrie et chimie théorique, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratorio de Quimica Teorica Computacional (QTC), Pontificia Universidad Católica de Chile (UC), Departamento de Quimica - Cinvestav, Department of Chemistry - MacMaster University, Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Pontifica Universidad Catôlica de Chile, Chemistry, Vriendenkring VUB, Quantum Chemistry - Molecular Modelling, and General Chemistry
Subjects: 010304 chemical physics, Computer science, Management science, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Round table, 0103 physical sciences, [CHIM]Chemical Sciences, Relevance (information retrieval), Density functional theory, Reaction path, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS, Energy functional
Abstract: This paper results from a round table discussion at the CCTC2018 Conference in Changsha City, Hunan, China, in December 2018. It presents a report on the status, prospects, and issues of conceptual density functional theory (CDFT). After a short exposition on the history of CDFT, its fundamentals, philosophy, and successes are highlighted. Then ten issues for reflection on the future of conceptual DFT are formulated and discussed, ending with one or more summarizing statements on the present status of various concepts/principles/practices and proposed directions for future research. The issues include the further analysis of the energy functional, E[N,v], extended to include effects of temperature, solvent, and mechanical forces, basic requirements for physically acceptable response functions as reactivity descriptors, the use of the grand canonical ensemble, the relevance of CDFT for chemical kinetics and thermodynamics, the domain of validity of CDFT-based principles, the combination of CDFT with reaction path calculations, information-theoretic descriptors, and the treatment of excited states and time dependence. The final issue advocates the transition of CDFT from an interpretative to a predictive mode; we believe this is of utmost importance for promoting CDFT as a viable alternative to wave function-based methods for the practicing chemist, a separate issue treated in the final section.
Published: 2020
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219. Interaction of hydantoin with solar wind minority ions: O6+ and He2+

Author: P. Moretto-Capelle, Julie Renoud, Alicja Domaracka, Suvasthika Indrajith, Bernd A. Huber, Patrick Rousseau, Jean-Philippe Champeaux, Interactions Ions-Matière (LCAR) (I²M), Laboratoire Collisions Agrégats Réactivité (LCAR), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU), Centre de recherche sur les Ions, les MAtériaux et la Photonique (CIMAP - UMR 6252), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), 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)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Caen Normandie (UNICAEN), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Astrochemistry, Double ionization, General Physics and Astronomy, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Molecular physics, Reaction coordinate, Ion, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Ionization, 0103 physical sciences, Mass spectrum, Molecule, Density functional theory, Physical and Theoretical Chemistry, 0210 nano-technology, 010303 astronomy & astrophysics
Abstract: The laboratory study of prebiotic molecules interacting with solar wind ions is important to understand their role in the emergence of life in the complex context of the astrochemistry of circumstellar environments. In this work, we present the first study of the interaction of hydantoin (C3N2O2H4, 100 a.m.u.) with solar wind minority multi-charged ions: O6+ at 30 keV and He2+ at 8 keV. The fragmentation mass spectra as well as correlation maps resulting from the interaction are presented and discussed in this paper. Prompt and delayed dissociations from metastable states of the ionized molecule have been observed and the corresponding lifetimes measured. Experimental results are completed by quantum Density Functional Theory (DFT) calculations for energies, structures and dynamics (Internal Reaction Coordinates and Dynamic Reaction Coordinates) of the molecule for its different reachable charge states and the major observed fragmentation pathways. These calculations show that the molecule can only support two charges before spontaneously dissociating in agreement with the experimental observations. Calculations also demonstrate that hydantoin's ring opens after double ionization of the molecule which may enhance its reactivity in the background of biological molecule formation in a cirmcumstellar environment. For the major experimentally observed fragmentations (like 44 a.m.u./56 a.m.u. dissociation), Internal Reaction Coordinate (IRC) calculations were performed pointing out for example the important role of hydrogen transfer in the fragmentation processes.
Published: 2020
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220. An empirical correlation for the relative permittivity of liquids in a wide temperature range: application to the modeling of electrolyte systems with a GE/EoS approach

Author: Evelyne Neau, Isabelle Raspo, Laboratoire de Mécanique, Modélisation et Procédés Propres (M2P2), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), and Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SPI.OTHER]Engineering Sciences [physics]/Other, Work (thermodynamics), General Chemical Engineering, Vapour pressure of water, General Physics and Astronomy, Thermodynamics, Relative permittivity, 02 engineering and technology, Electrolyte, electrolytes, relative permittivity, 01 natural sciences, symbols.namesake, 020401 chemical engineering, Phase (matter), NRTL-PRA EoS, phase equilibria, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, 0204 chemical engineering, Physical and Theoretical Chemistry, 010405 organic chemistry, Chemistry, GE/EoS approach, Atmospheric temperature range, Supercritical fluid, 0104 chemical sciences, Gibbs free energy, Condensed Matter::Soft Condensed Matter, G E /EoS approach, symbols
Abstract: International audience; Relative permittivity, also known as static dielectric constant, is a key property of solvents in electrolyte solutions. It strongly influences the solubility of solutes and, therefore, it can be used as a predictive tool in chemical engineering processes. Relative permittivity also plays an essential role in the modeling of phase equilibria of electrolyte systems, since it is involved in the Debye-Hückel model and in the Mean Spherical Approximation, commonly used to represent long-range interactions between ions. In this paper, we propose a new temperature-dependent correlation for the relative permittivity of liquid water, methanol and ethanol, valid in a wide temperature range, including very high temperatures. Comparison with other literature equations evidenced that the main interest of the proposed correlation is to allow satisfactory predictions of the relative permittivity, not only in the range of validity of other literature models, but also in the high temperature domain, including supercritical temperatures for water. The new correlation is then used with the NRTL-PRA EoS to predict vapor pressure of water with several salts, including single electrolytes and two-salts mixtures; it must be noted that the modeling presented in this work is relevant for any GE/EoS model, since in this case (binary interactions between water and ions being equal to zero), the excess Gibbs energy reduces to the Long-Range term derived from the Pitzer-Debye-Hückel model. A temperature-dependent correction of the solvent relative permittivity is proposed to account for its dependence on ion mole fraction in this Long-Range term. Results thus obtained show that this correction leads to an accurate prediction both: for vapor pressures of aqueous electrolyte solutions in a very wide temperature domain and for the modeling of vapor-liquid equilibria of methanol-water and ethanol-water mixtures with several salts.
Published: 2020
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221. Numerical simulation of water spray transport along a plate of a heat exchanger

Author: Sadok Ben Jabrallah, Souad Harmand, Walid Foudhil, Nihel Grich, Laboratoire d’Énergétique et des Transferts Thermiques et Massiques [Tunis] (LETTM), Faculté des Sciences Mathématiques, Physiques et Naturelles de Tunis (FST), Université de Tunis El Manar (UTM)-Université de Tunis El Manar (UTM), Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines - UMR 8201 (LAMIH), and Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France)
Subjects: geography, Materials science, geography.geographical_feature_category, Water flow, Multiphysics, Flow (psychology), 02 engineering and technology, Mechanics, [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph], 021001 nanoscience & nanotechnology, Condensed Matter Physics, Inlet, 01 natural sciences, 010406 physical chemistry, 0104 chemical sciences, Physics::Fluid Dynamics, Phase (matter), Thermal, Heat exchanger, Relative humidity, Physical and Theoretical Chemistry, 0210 nano-technology, Physics::Atmospheric and Oceanic Physics
Abstract: International audience; Water spraying is widely being used in many industrial applications because of the benefits it has shown over cooling. This paper presents a numerical investigation to simulate evaporating water spray along a plate of an exchanger. Indeed, we were interested in a horizontal channel whose lower wall is the plate of the exchanger maintained at a heating flow. This plate is exposed to a turbulent airflow in which water droplets were injected. The equations governing the continuous phases (air) and the dispersed phase (water) were developed. These equations were solved using Comsol Multiphysics. A comparison of the simulation results and those of the experiment reveals an acceptable concordance. Therefore, the numerical results present the thermal behavior by studying transversal and longitudinal evolution of temperature. Moreover, the maximum evaporated water flow (mmaxew) and the plate temperature are investigated for several physical parameters of the continuous phase, such as velocity, relative humidity and inlet temperature. The results show that these parameters have significant impact on the cooling of the plate. In addition, mmaxew witnesses a remarkable decrease by increasing relative humidity. However, increasing air velocity and inlet air temperature could improve mmaxew.
Published: 2020
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222. Atomic Force Microscopy Nanomanipulation by Confocal Raman Multiwavelength Spectroscopy: Application at the Monitoring of Resonance Profile Excitation Changes of Manipulated Carbon Nanotube

Author: Angelina D’Orlando, Jean-Yves Mevellec, Bernard Humbert, Guy Louarn, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut des Matériaux Jean Rouxel (IMN), Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Ecole Polytechnique de l'Université de Nantes (EPUN), and Université de Nantes (UN)-Université de Nantes (UN)
Subjects: Nanostructure, Materials science, business.industry, Confocal, Resonance, Carbon nanotube, Molecular electronic transition, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, law.invention, Condensed Matter::Materials Science, symbols.namesake, Coupling (physics), General Energy, law, symbols, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, Physical and Theoretical Chemistry, Raman spectroscopy, business, Excitation, ComputingMilieux_MISCELLANEOUS
Abstract: This paper explores the possibilities offered by coupling AFM nano-manipulation with Resonance Raman Excitation Profile approaches. We apply this method to nanostructures produced by AFM nano-manipulation. The experimental demonstration is made on the interaction between two single-wall carbon nanotubes, one semiconducting and the other metallic. The measurement is analyzed and discussed in terms of resonance shifts and broadening of the electronic transition.
Published: 2020
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223. Optical Index Prism Sensitivity of Surface Plasmon Resonance Imaging in Gas Phase: Experiment versus Theory

Author: Cyril Herrier, Sophie Brenet, Yanxia Hou, Jonathan S. Weerakkody, Arnaud Buhot, Thierry Livache, Chimie pour la Reconnaissance et l’Etude d’Assemblages Biologiques (CREAB ), SYstèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé (SYMMES), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), Département Interfaces pour l'énergie, la Santé et l'Environnement (DIESE), ANR-12-LABX-003, Agence Nationale de la Recherche, Délégation Générale pour l'Armement, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Fondation Nanosciences, FUI WISE AAP21, Bpifrance, Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Structures et propriétés d'architectures moléculaire (SPRAM - UMR 5819), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Centre National de la Recherche Scientifique (CNRS), Chimie pour la Reconnaissance et l’Etude d’Assemblages Biologiques (CREAB), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and ANR-17-EURE-0003,CBH-EUR-GS,CBH-EUR-GS(2017)
Subjects: [PHYS]Physics [physics], Spr imaging, Materials science, business.industry, education, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Characterization (materials science), Gas phase, General Energy, Surface plasmon resonance imaging, Optical index, Optoelectronics, Sensitivity (control systems), Prism, Physical and Theoretical Chemistry, 0210 nano-technology, business
Abstract: International audience; Recent advances in SPR-imaging detection in gas phase have led to the development of opto-electronic noses (opto-eNs) requiring the need for optical sensitivity characterization of such devices. Understanding of the optical contributions will have an implicit relevance on sensitivity enhancement of SPR-imaging in gas phase valuable to improve the performance of opto-eN and potentially open new applications as gas sensors. In this paper, we analyzed the optical contributions to the sensitivity of the SPR imaging prisms and potential insights into their contributing factors. We established a characterization method for the SPR prism sensitivity that is independent of the carrier gas considered. Then, by using this sensitivity parameter, the influence of two different kinds of adhesive layers, Cr and Ti, of the gold coated prisms were studied. Furthermore, we considered a theoretical model to rationalize our experimental results, which demonstrated the relevance of surface topography on the optical index 1 sensitivity. Those surface topographies were characterized experimentally and were implemented in the model free from any additional fitting parameters using a modified Maxwell-Garnet theory. Finally, the model was shown to predictively assess the experimentally measured effects of temperature on the prism sensitivity.
Published: 2020
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224. The impact of photocatalytic paint porosity on indoor NOx and HONO levels

Author: Henri Wortham, Gregory Brochard, Virginie Bergé, Vincent Bartolomei, Delphine Truffier-Boutry, Adrien Gandolfo, Brice Temime-Roussel, Sasho Gligorovski, Laboratoire Chimie de l'environnement (LCE), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC), and Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Nitrous acid, 010504 meteorology & atmospheric sciences, Indoor air, Environmental remediation, General Physics and Astronomy, 010501 environmental sciences, 01 natural sciences, chemistry.chemical_compound, chemistry, Environmental chemistry, [SDE]Environmental Sciences, Photocatalysis, Physical and Theoretical Chemistry, Porosity, Nitrogen oxides, NOx, Volume concentration, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: Photocatalytic materials are a potentially effective remediation technology for indoor air purification. In this paper, we assess the impact of photocatalytic paint porosity on the indoor levels of nitrogen oxides (NOx) and nitrous acid (HONO). We observed that the porosity of photocatalytic paints plays a paramount role in the NO2 removal. The increase of pigment volume concentration (PVC), i.e. porosity, from PVC 53% to PVC 80% leads to an increase of the geometric NO2 uptake coefficient from (3.3 ± 0.5) × 10-6 to (3.2 ± 0.1) × 10-4. At the same time, a high quantity of HONO formed by NO2 conversion on the photocatalytic paint is emitted into the air. The formation of HONO, which is considered as a harmful compound and a major player in the oxidative capacity of indoor air, is reduced as the paint porosity increases. Based on these results, further optimization should be considered for future commercialization of photocatalytic paints aimed for indoor applications.
Published: 2020
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225. High-Performance Optical Power Limiting Filters at Telecommunication Wavelengths: When Aza-BODIPY Dyes Bond to Sol-Gel Materials

Author: Gérard Berginc, Denis Jacquemin, Boris Le Guennic, Olivier Maury, Denis Chateau, Sylvain David, Cesar Lopes, Hao-Jung Chang, Linda H. Karlsson, Stephane Parola, Chantal Andraud, Mykhailo V. Bondar, Laboratoire de Chimie - UMR5182 (LC), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), University of Central Florida [Orlando] (UCF), Swedish Defense Research Agency (FOI), National Academy of Sciences of Ukraine (NASU), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation (CEISAM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Thales LAS France, Totalförsvarets Forskningsinstitut, FOI, Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Materials science, Infrared, Optical power, 02 engineering and technology, 010402 general chemistry, Short wave infrared, 01 natural sciences, Two-photon absorption, Limiter, Sol-gels, Optical power limiters, [CHIM]Chemical Sciences, Sol-gel process, Physical and Theoretical Chemistry, Optical power limiting, Infrared radiation, Doping concentration, Dyes, Two photon absorption, Sol-gel, Optical properties, business.industry, Chromophore, Two photon processes, 021001 nanoscience & nanotechnology, Chromophores, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Wavelength, Light intensity, General Energy, Optoelectronics, Incident intensity, 0210 nano-technology, business, Telecommunication wavelengths, Photochemical stability
Abstract: International audience; An optical power limiter (OPL) device can change its optical properties depending on the input light intensity: it is ideally transparent at low incident power and presents a decrease in transmission when the incident intensity increases. This phenomenon can be used for protection of optical sensors. This paper presents the design of a functionalized aza-BODIPY chromophore, combining good nonlinear two-photon absorption and exited-state absorption in the short-wave infrared range (1300-1600 nm). The aza-BODIPY chromophores also show excellent thermal and photochemical stabilities. Their covalent grafting to a sol-gel matrix leads to the formation of class II sol-gel materials that allows for extraordinary doping concentrations of up to 280 mol·L-1 (40 wt %), which results in highly efficient OPL performances at 1550 nm. © 2020 American Chemical Society.
Published: 2020
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226. Free Radical Photopolymerization and 3D Printing Using Newly Developed Dyes: Indane-1,3-Dione and 1H-Cyclopentanaphthalene-1,3-Dione Derivatives as Photoinitiators in Three-Component Systems

Author: Malek Nechab, Fabrice Morlet-Savary, Didier Gigmes, Jacques Lalevée, Frédéric Dumur, Pu Xiao, Corentin Pigot, Ke Sun, Bernadette Graff, Shaohui Liu, Hong Chen, Institut de Science des Matériaux de Mulhouse (IS2M), Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Research School of Chemistry, Australian National University (ANU), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), and Dumur, Frederic
Subjects: [CHIM.POLY] Chemical Sciences/Polymers, Materials science, Tertiary amine, Radical, Radical polymerization, Indane, 02 engineering and technology, 010402 general chemistry, Photochemistry, lcsh:Chemical technology, 01 natural sciences, Catalysis, lcsh:Chemistry, chemistry.chemical_compound, lcsh:TP1-1185, push-pull dye, Physical and Theoretical Chemistry, chemistry.chemical_classification, free radical polymerization, LED, three-component system, 3D printing, Electron acceptor, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Light intensity, Photopolymer, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Polymerization, lcsh:QD1-999, push–pull dye, 0210 nano-technology
Abstract: The design of photoinitiating systems with excellent photochemical reactivities at 405nm LED is one of the obstacles to efficiently promote free radical polymerization in mild conditions (e.g., low light intensity, under air). Here, our actual search for new multicomponent photoinitiating systems at 405nm LED prompts us to develop new dyes based on push&ndash, pull structures. In the present paper, we chose two series of new dyes which possess indane-1,3-dione and 1H-cyclopenta naphthalene-1,3-dione groups as the electron-withdrawing groups, since they have the great potential to behave as sensitive and remarkable photoinitiators in vat photopolymerization/3D printing. When incorporated with a tertiary amine (ethyl dimethylaminobenzoate EDB, used as electron/hydrogen donor) and an iodonium salt (used as electron acceptor) as the three-component photoinitiating systems (PISs), and among a series of 21 dyes, 10 of them could efficiently promote the free radical photopolymerization of acrylates. Interestingly, steady state photolysis experiments revealed different behaviors of the dyes. Fluorescence experiments and free energy change calculations for redox processes were also carried out to investigate the relevant chemical mechanisms. Additionally, the formation of radicals from the investigated PISs was clearly observed by electron spin resonance (ESR) spin-trapping experiments. Finally, stereoscopic 3D patterns were successfully fabricated by the laser writing technique. In this work, the use of push&ndash, pull dyes based on the naphthalene scaffold as photoinitiators of polymerization is reported for the first time in a systematic study aiming at investigating the structure&ndash, performance relationship for irradiation carried out at 405 nm. By carefully selecting the electron donors used in the two series of push&ndash, pull dyes, novel and high-performance photoinitiating systems operating at 405 nm are thus proposed.
Published: 2020
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227. Adsorber heat exchanger using Al-fumarate beads for heat-pump application – a transport study

Author: Gerrit Fueldner, Xavier Daguenet-Frick, Cécile Daniel, Paul Gantenbein, Richard Blom, Francis Meunier, Terje Didriksen, José Casaban, Patrick Persdorf, Andreas Velte, David Farrusseng, Conor Hamill, IRCELYON-Ingéniérie, du matériau au réacteur (ING), Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Publica
Subjects: Materials science, adsorption chiller, Wärmepumpe, Thermische Systeme und Gebäudetechnik, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, law.invention, Adsorption, law, Desorption, Waste heat, Heat exchanger, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS, MOF, Thermische Speicher für Gebäude, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Knudsen diffusion, Chemical engineering, adsorption, Temperature jump, Heat transfer, 0210 nano-technology, energieeffizientes Gebäude, Heat pump, adsorption kinetics
Abstract: Metal-Organic Frameworks (MOFs), thanks to their type V water adsorption isotherms ("S-Shape") and large water capacities, are considered as potential breakthrough adsorbents for heat-pump applications. In particular, Al(OH)-fumarate could enable efficient regeneration at a lower temperature than silica-gel which would allow us to address the conversion of waste heat at low temperature such as found in data centers. Despite its greater adsorption capacity features, heat and mass transport limitations could jeopardize the potential performance of Al(OH)-fumarate. Heat and mass transport depend on the size of the bodies (mm range), their packing and on the pore structures, i.e. macro-mesopore volumes and sizes. This paper describes the cost-efficient and scalable synthesis and shaping processes of Al(OH)-fumarate beads of various sizes appropriate for use in water Adsorption Heat-Pumps (AHPs). The objective was to study transport limitations (i.e. mass and heat) in practical e beads which meet mechanical stability requirements. Dynamic data at the grain scale was obtained by the Large Temperature Jump method while dynamic data at the adsorber scale was obtained on a heat exchanger filled with more than 1 kg of Al(OH)-fumarate beads. Whereas the binder content had little impact on mass and heat transfer in this study, we found that Knudsen diffusion in mesopores of the grain may be the main limiting factor at the grain scale. At the adsorber scale, heat-transfer within the bed packing as well as to the heat exchanger is likely responsible for the slow adsorption and desorption kinetics which have been observed for very low desorption temperature. Finally, the dynamic aspects of the observed water adsorption isotherm shift with temperature are discussed in light of reported reversible structure modification upon temperature triggered water adsorption-desorption.
Published: 2020
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228. Why the Cosmological Constant Seems to Hardly Care About Quantum Vacuum Fluctuations: Surprises From Background Independent Coarse Graining

Author: Martin Reuter, Carlo Pagani, Laboratoire de physique et modélisation des milieux condensés (LPM2C ), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)
Subjects: Materials Science (miscellaneous), Background independent quantum gravity, Biophysics, Asymptotic safety in quantum gravity, General Physics and Astronomy, Cosmological constant, nonperturbative, asymptotic safety, 01 natural sciences, renormalization, Gravitation, Renormalization, Theoretical physics, Vacuum energy, Functional renormalisation group, 0103 physical sciences, ultraviolet, Background independence, Physical and Theoretical Chemistry, 010306 general physics, Mathematical Physics, Physics, energy: high, cosmological constant, background, functional renormalization group, lcsh:QC1-999, fluctuation: vacuum, space-time, gravitation, quantum gravity, [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], Quantum gravity, renormalisation group, renormalization group, lcsh:Physics, Cosmological constant problem
Abstract: International audience; Background Independence is a sine qua non for every satisfactory theory of Quantum Gravity. In particular if one tries to establish a corresponding notion of Wilsonian renormalization, or coarse graining, it presents a major conceptual and technical difficulty usually. In this paper we adopt the approach of the gravitational Effective Average Action and demonstrate that generically coarse graining in Quantum Gravity and in standard field theories on a non-dynamical spacetime are profoundly different. By means of a concrete example, which in connection with the cosmological constant problem is also interesting in its own right, we show that the surprising and sometimes counterintuitive implications of Background Independent coarse graining are neither restricted to high energies, nor to strongly nonperturbative regimes. In fact, while our approach has been employed in most studies of Asymptotic Safety, this particular ultraviolet behaviour plays no essential role in the present context.
Published: 2020
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229. A Numerical Assessment of an Effective Envelope-Tracking Semiconductor Optical Amplifier Design for Coherent-Optical OFDM Transmission

Author: Pascal Morel, Julio Cesar Ortiz-Cornejo, Stéphane Azou, Jorge A. Pardinas-Mir, Lab-STICC_ENIB_MOM_DIM, Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance (Lab-STICC), École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Télécom Bretagne-Institut Brestois du Numérique et des Mathématiques (IBNM), Université de Brest (UBO)-Université européenne de Bretagne - European University of Brittany (UEB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Télécom Bretagne-Institut Brestois du Numérique et des Mathématiques (IBNM), Université de Brest (UBO)-Université européenne de Bretagne - European University of Brittany (UEB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance (UMR 3192) (Lab-STICC), Université européenne de Bretagne - European University of Brittany (UEB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Institut Brestois du Numérique et des Mathématiques (IBNM), and Université de Brest (UBO)-Télécom Bretagne-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Optical amplifier, Computer science, business.industry, Orthogonal frequency-division multiplexing, Amplifier, Transmitter, Bandwidth (signal processing), 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, 010309 optics, Optics, Linearization, Modulation, 0103 physical sciences, Electronic engineering, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, 0210 nano-technology, business, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, Companding
Abstract: International audience; The inherent nonlinear effects associated to Semiconductor Optical Amplifiers (SOAs) may translate into a transmission performance loss for non-constant envelope modulation formats. However, a variety of linearization schemes may be adopted for coping with these impairments and offering an effective system design. In this paper, an envelope tracking (ET) technique is investigated for linearizing an SOA-based Coherent Optical OFDM transmitter. An optimized design of the ET subsystem is performed under various scenarios, with the eventual joint use of Peak-to-Average Power Ratio (PAPR) reduction either via hard-clipping or nonlinear companding. A thorough carrier density analysis is performed in the amplifier, for various target gain values, so as to assess the effectiveness of the proposed scheme. Morever, we investigate the robustness of the proposed approach against some parameters variation both inside the ET path (DAC characteristics and bandwidth limited envelope generation). Extensive simulations performed with a precise SOA model show that up to 8 dB (resp. 7 dB) BER improvement can be achieved via the proposed scheme in the case of 4-QAM/OFDM (resp. 16-QAM/OFDM), compared to the conventional system with no linearization, and that even an envelope quantized with 2 bits still enables a significant performance increase.
Published: 2020
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230. Using computed infrared intensities for the reduction of vibrational configuration interaction bases

Author: Didier Bégué, Vincent Le Bris, Olivier Coulaud, Isabelle Baraille, Marc Odunlami, Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), High-End Parallel Algorithms for Challenging Numerical Simulations (HiePACS), Laboratoire Bordelais de Recherche en Informatique (LaBRI), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Inria Bordeaux - Sud-Ouest, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), and Université de Bordeaux (UB)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Centre National de la Recherche Scientifique (CNRS)-Inria Bordeaux - Sud-Ouest
Subjects: Physics, Iterative and incremental development, 010304 chemical physics, Discretization, Computation, Spectrum (functional analysis), General Physics and Astronomy, Basis function, [CHIM.MATE]Chemical Sciences/Material chemistry, Configuration interaction, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Reduction (complexity), [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, [CHIM.POLY]Chemical Sciences/Polymers, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, 0103 physical sciences, Statistical physics, Physical and Theoretical Chemistry, Eigenvalues and eigenvectors
Abstract: International audience; The Adaptive Vibrational Configuration Interaction (A-VCI) algorithm is an iterative process that computes the anharmonic spectrum of a molecule using nested bases to discretize the Hamiltonian operator. For large molecular systems, the size of the discretization space and the computation time quickly become prohibitive. It is therefore necessary to develop new methods to further limit the number of basis functions. Most of the time, the interpretation of an experimental infrared spectrum does not require the calculation of all eigenvalues but only those corresponding to vibrational states with significant intensity. In this paper, a technique that uses infrared intensities is introduced to select a subset of eigenvalues to be precisely calculated. Thus, we build smaller nested bases and reduce both the memory footprint and the computational time. We validate the advantages of this new approach on a well-studied 7-atom molecular system (C2H4O), and we apply it on a larger 10-atom molecule (C4H4N2).
Published: 2020
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231. Electrokinetic leakage as a tool to probe internal fouling in MF and UF membranes

Author: Anthony Szymczyk, Estelle Couallier, M. Frappart, C. Rouquié, A. Riaublanc, Murielle Rabiller-Baudry, S. Liu, Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Laboratoire de génie des procédés - environnement - agroalimentaire (GEPEA), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-Université de Nantes (UN)-Institut Universitaire de Technologie - Nantes (IUT Nantes), Université de Nantes (UN)-Institut Universitaire de Technologie Saint-Nazaire (IUT Saint-Nazaire), Université de Nantes (UN)-Institut Universitaire de Technologie - La Roche-sur-Yon (IUT La Roche-sur-Yon), Université de Nantes (UN)-Ecole Nationale Vétérinaire, Agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Université Bretagne Loire (UBL), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Agence de l'Environnement et de la Maîtrise de l'Energie (ADEME), GIS Europole Mer, France (Sciences et Ingenieries Marines, 2016-2017), Universite de Bretagne Loire, ADEME, Challenge Food For Tomorrow/Cap Aliment, Pays de la Loire, France, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes-Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Ecole Nationale Vétérinaire, Agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Université Bretagne Loire (UBL)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de Technologie - Nantes (IUT Nantes), Université de Nantes (UN)-Université de Nantes (UN)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut Universitaire de Technologie Saint-Nazaire (IUT Saint-Nazaire), Université de Nantes (UN)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-École nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut Universitaire de Technologie - La Roche-sur-Yon (IUT La Roche-sur-Yon), Université de Nantes (UN), Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Rennes-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES), Université de Nantes (UN)-Ecole Nationale Vétérinaire, Agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), and Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)
Subjects: Membrane fouling, Materials science, Ultrafiltration, Filtration and Separation, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Biochemistry, Streaming current, Electrokinetic phenomena, [CHIM.GENI]Chemical Sciences/Chemical engineering, Zeta potential, [CHIM]Chemical Sciences, General Materials Science, Microfiltration, Physical and Theoretical Chemistry, Leakage (electronics), Fouling, 021001 nanoscience & nanotechnology, Electrokinetics, 0104 chemical sciences, Membrane, Chemical engineering, 0210 nano-technology, Porous medium
Abstract: International audience; Tangential electrokinetic measurements are widely used to characterize membrane fouling as the membrane zeta potential is partly governed by the presence of foulant materials on its surface. However, in the case of porous materials as micro- (MF) and ultrafiltration (UF) membranes, a part of the streaming current flows through the porosity of the membrane during measurements. This electrokinetic leakage, is directly impacted by the presence of foulant materials inside the membrane porosity. Hence, this paper investigates for the first time the possibility of using electrokinetic leakage as a probe for detecting internal fouling, taking lipid fouling as example. Firstly, a lab-scale methodology combining "upside-down" fouling experiments with electrokinetic measurements demonstrated that the intensity of the electrokinetic leakage was related to the presence of internal fouling. Secondly, the concept was applied to the pilot-scale MF and UF of an oil-in-water emulsion under various transmembrane pressures (TMP). A significant impact of the TMP on the internal fouling of a MF PES membrane was highlighted, whereas almost no impact of the TMP was noticed in the case of an UF PAN membrane. The developed methodology using the quantification of the electrokinetic leakage phenomenon allows distinguishing the contributions of internal and external (surface) fouling. These findings offer new application of tangential electrokinetic measurements to gain more insight into the characterization of membrane fouling.
Published: 2020
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232. Complete Nuclear Permutation Inversion Invariant Artificial Neural Network (CNPI-ANN) Diabatization for the Accurate Treatment of Vibronic Coupling Problems

Author: Wolfgang Eisfeld, David M. G. Williams, and Universität Bielefeld = Bielefeld University
Subjects: 010304 chemical physics, Artificial neural network, Chemistry, Computer Science::Neural and Evolutionary Computation, Diabatic, Inversion (meteorology), Invariant (physics), 010402 general chemistry, 01 natural sciences, Potential energy, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Vibronic coupling, 0103 physical sciences, Applied mathematics, Physical and Theoretical Chemistry, Physics::Chemical Physics, Quantum dynamics
Abstract: International audience; A recently developed scheme to produce accurate high-dimensional coupled diabatic potential energy surfaces (PESs) based on artificial neural networks (ANNs) [J. Chem. Phys. 2018, 149, 204106 and J. Chem. Phys. 2019, 151, 164118] is modified to account for the proper complete nuclear permutation inversion (CNPI) invariance. This new approach cures the problem intrinsic to the highly flexible ANN representation of diabatic PESs to account for the proper molecular symmetry accurately. It turns out that the use of CNPI invariants as coordinates for the input layer of the ANN leads to a much more compact and thus more efficient representation of the diabatic PES model without any loss of accuracy. In connection with a properly symmetrized vibronic coupling reference model, which is modified by the output neurons of the CNPI-ANN, the resulting adiabatic PESs show perfect symmetry and high accuracy. In the present paper, the new approach will be described and thoroughly tested. The test case is the representation and corresponding vibrational/vibronic nuclear dynamics of the low-lying electronic states of planar NO 3 for which a large number of ab initio data is available. Thus, the present results can be compared directly with the previous studies.
Published: 2020
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233. Characterization of Confined Liquid Jet Injected into Oscillating Air Crossflow

Author: Pierre Gajan, Geoffroy Illac, Virginel Bodoc, Frank Simon, Anthony Desclaux, ONERA / DMPE, Université de Toulouse [Toulouse], and ONERA-PRES Université de Toulouse
Subjects: Materials science, General Chemical Engineering, Shear force, Airflow, Flow (psychology), General Physics and Astronomy, 02 engineering and technology, Combustion, cross flow, 01 natural sciences, 010305 fluids & plasmas, Liquid fuel, Physics::Fluid Dynamics, [SPI]Engineering Sciences [physics], 0203 mechanical engineering, Phase (matter), 0103 physical sciences, liquid jet, Physical and Theoretical Chemistry, acoustics, [PHYS]Physics [physics], Jet (fluid), thermo-acoustic instabilities, Mechanics, Breakup, 020303 mechanical engineering & transports
Abstract: International audience; The aim of this work is to study the role of the liquid phase in the thermo-acoustic coupling that leads to combustion instabilities. In multipoint injection systems, the liquid fuel is injected through orifices as jets which are destabilized by the high-speed air flowing in a transverse direction. This paper is focused on the effect of an acoustic excitation imposed on the air flow on the various liquid features observed in actual fuel injection systems. This concerns the initial jet trajectory, its breakup, the formation and transport of the resulting spray, the liquid film formation on walls and its final atomization at the outlet of the injection system. Experimental investigations were performed on a simplified geometry designed to reproduce these main phenomena. Phase-averaged processing of the experimental data is used to analyze the relationship between the acoustic excitation and the liquid phase behavior. In particular, the phase delays imposed by the various processes involved are analyzed. The processing of high-speed video recordings reveals harmonic oscillation of the liquid column which periodically breaks into a spray structure or impacts the opposite wall, forming a liquid film. Using PDA measurements, it is shown that the resulting two-phase flow consists of alternating dense and diluted zones transported by the air flow. At the end of the channel, the liquid film flowing on the wall opposite the liquid jet is periodically atomized through the oscillating shear forces imposed by the air flow.
Published: 2020
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234. Photochemistry of the Cloud Aqueous Phase: A Review

Author: Marcello Brigante, Angelica Bianco, Monica Passananti, Gilles Mailhot, Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, Institut de Chimie de Clermont-Ferrand (ICCF), SIGMA Clermont (SIGMA Clermont)-Institut de Chimie du CNRS (INC)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Chimica IFM and NIS, Università degli studi di Torino (UNITO), Helsingin yliopisto = Helsingfors universitet = University of Helsinki, and Università degli studi di Torino = University of Turin (UNITO)
Subjects: 010504 meteorology & atmospheric sciences, Pharmaceutical Science, Review, 010501 environmental sciences, Photochemistry, 01 natural sciences, Analytical Chemistry, Ion, lcsh:QD241-441, chemistry.chemical_compound, lcsh:Organic chemistry, Nitrate, oxidant capacity, Drug Discovery, cloud, Reactivity (chemistry), Physical and Theoretical Chemistry, Nitrite, Hydrogen peroxide, 0105 earth and related environmental sciences, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, photochemistry, hydroxyl radical, Chemistry, Organic Chemistry, Aqueous two-phase system, Hydrogen Peroxide, Oxidants, Photochemical Processes, Atmosphere, Cloud, Hydroxyl radical, Oxidant capacity, 13. Climate action, Chemistry (miscellaneous), Liquid water content, atmosphere, Molecular Medicine, [CHIM.OTHE]Chemical Sciences/Other
Abstract: This review paper describes briefly the cloud aqueous phase composition and deeply its reactivity in the dark and mainly under solar radiation. The role of the main oxidants (hydrogen peroxide, nitrate radical, and hydroxyl radical) is presented with a focus on the hydroxyl radical, which drives the oxidation capacity during the day. Its sources in the aqueous phase, mainly through photochemical mechanisms with H2O2, iron complexes, or nitrate/nitrite ions, are presented in detail. The formation rate of hydroxyl radical and its steady state concentration evaluated by different authors are listed and compared. Finally, a paragraph is also dedicated to the sinks and the reactivity of the HO• radical with the main compounds found in the cloud aqueous phase. This review presents an assessment of the reactivity in the cloud aqueous phase and shows the significant potential impact that this medium can have on the chemistry of the atmosphere and more generally on the climate.
Published: 2020
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235. Tunable upconversion white photoemission in Yb3+/Mn2+/Tm3+ tri-doped transparent glass ceramics

Author: Qing Jiao, Cuimei Cheng, XueYun Liu, Xianghua Zhang, Na Zeng, Ningbo University (NBU), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), State Key Laboratory of Luminescent Materials and Devices, SKLLMDXYL18015Natural Science Foundation of Zhejiang Province LY20A040002Natural Science Foundation of Ningbo 2018A610042South China University of Technology, SCUT 2018-skllmd-11Ningbo UniversityNational Natural Science Foundation of China, NSFC 51702172, Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Glass ceramics, Analytical chemistry, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, law.invention, Yb3+-Mn2+ pair, Inorganic Chemistry, law, Upconversion white light, [CHIM]Chemical Sciences, Ceramic, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, Spectroscopy, Glass-ceramic, Organic Chemistry, Doping, Atmospheric temperature range, Tm3+ ions, 021001 nanoscience & nanotechnology, Laser, Atomic and Molecular Physics, and Optics, Photon upconversion, 0104 chemical sciences, Electronic, Optical and Magnetic Materials, Transmission electron microscopy, visual_art, visual_art.visual_art_medium, 0210 nano-technology, Luminescence
Abstract: International audience; The design of optical materials with efficient white-light emission performance is still of great interest in the fields of visible lighting and communication. In this paper, Yb3+/Mn2+/Tm3+ tri-doped upconversion (UC) white-emitting transparent glass ceramics have been successfully fabricated by a melt-quenching technique. The structure and luminescent properties of the resultant samples were investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), optical transmission spectra, and photoemission spectra. Owing to the co-precipitation of dual-phase γ-Ga2O3/β-YF3 nanocrystals in the matrix, the Yb3+/Mn2+ co-doped glass ceramics exhibited tunable dual-to single-broadband UC emission with the content of Mn2+ varying from 0.75 to 4 mol%. After Tm3+ ions were introduced into the co-doped GC sample, a UC white-light luminescence was realized by combining the yellowish emission (510–630 nm) of Yb3+-Mn2+ pair and blue emission (476 nm) of Tm3+. Importantly, the white-emitting glass ceramic sample showed excellent thermal recoverability during a heating and cooling cycle within the temperature range of 303–573 K. Our results indicated the designed Yb3+/Mn2+/Tm3+ tri-doped glass ceramics may be a promising candidate for the white-light lasers source. © 2020 Elsevier B.V.
Published: 2020
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236. Characterization of β-turns by electronic circular dichroism spectroscopy: A coupled molecular dynamics and time-dependent density functional theory computational study

Author: Laure Guilhaudis, Vincent Tognetti, Mattia Migliore, Hassan Oulyadi, Isabelle Ségalas-Milazzo, Andrea Bonvicini, Laurent Joubert, Marc Baaden, Chimie Organique et Bioorganique : Réactivité et Analyse (COBRA), Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), 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)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de biochimie théorique [Paris] (LBT (UPR_9080)), Institut de biologie physico-chimique (IBPC (FR_550)), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), ANR-11-LABX-0011,DYNAMO,Dynamique des membranes transductrices d'énergie : biogénèse et organisation supramoléculaire.(2011), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot - Paris 7 (UPD7)-Institut de biologie physico-chimique (IBPC), and Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Circular dichroism, General Physics and Astronomy, Molecular Dynamics Simulation, 010402 general chemistry, 01 natural sciences, Molecular physics, electronic circular dichroism, Molecular dynamics, Computational Chemistry, Polarizability, 0103 physical sciences, Computer Simulation, Physical and Theoretical Chemistry, Physics, Quantitative Biology::Biomolecules, secondary structures, 010304 chemical physics, Circular Dichroism, Time-dependent density functional theory, polarizable embedding multiscale model, Random coil, β-turns, molecular dynamics, Protein Structure, Tertiary, 0104 chemical sciences, Characterization (materials science), [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, time-dependent density functional theory, polarizable embedding multiscale model * Corresponding authors, Protein Conformation, beta-Strand, Density functional theory, Chirality (chemistry)
Abstract: International audience; Electronic circular dichroism is one of the most used spectroscopic techniques for peptide and protein structural characterization. However, while valuable experimental spectra exist for α-helix, β-sheet and random coil secondary structures, previous studies showed important discrepancies for β-turns, limiting their use as a reference for structural studies. In this paper, we simulated circular dichroism spectra for the best-characterized β-turns in peptides, namely types I, II, I′ and II′. In particular, by combining classical molecular dynamics simulations and state-of-the-art quantum time-dependent density functional theory (with the polarizable embedding multiscale model) computations, two common electronic circular dichroism patterns were found for couples of β-turn types (namely, type I/type II′ and type II/type I′), at first for a minimal di-peptide model (Ace-Ala-Ala-NHMe), but also for all sequences tested with non-aromatic residues in the central positions. On the other hand, as expected, aromatic substitution causes important perturbations to the previously found ECD patterns. Finally, by applying suitable approximations, these patterns were subsequently rationalized based on the exciton chirality rule. All these results provide useful predictions and pave the way for a possible experimental characterization of β-turns based on circular dichroism spectroscopy.
Published: 2020
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237. Regioselective C–F Bond Activation/C–C Bond Formation between Fluoropyridines and Cyclopropyl Groups at Zirconium

Author: Laure Vendier, Anthony Pujol, Natalie Crespo, Nuria Romero, Michel Etienne, Quentin Dufrois, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), MENESR, CONACYT, and ANR-11-BS-07-009-2
Subjects: Inert, Zirconium, 010405 organic chemistry, Bond, Organic Chemistry, chemistry.chemical_element, Regioselectivity, Bond formation, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, 0104 chemical sciences, Inorganic Chemistry, Reaction sequence, chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry
Abstract: International audience; This paper addresses the problem of the strong and inert C–F bond activation of various fluoropyridines by zirconocene derivatives. Dicyclopropylzirconocene, [Cp2Zr(c-C3H5)2], thermally eliminates cyclopropane, giving the transient intermediate zirconabicyclobutane [Cp2Zr(η2-c-C3H4)] that cleaves a C–F bond of pentafluoropyridine selectively at position 2, forming new Zr–F and C–C bonds stereoselectively to give [Cp2ZrF{c-cis-CHCH2CH(2-NC5F4)}]. DFT computations indicate the selectivity results from the initial formation of an azazirconacycle intermediate that undergoes ring opening and C–F bond cleavage. Transmetalation with a variety of cyclopropyl donors yields [Cp2Zr(c-C3H5){c-cis-CHCH2CH(2-NC5F4)}] with the selectivity depending on the nature of the donor. A synthetic cycle is realized when [Cp2Zr(c-C3H5){c-cis-CHCH2CH(2-NC5F4)}] reacts with pentafluoropyridine, yielding 2-(c-C3H5)NC5F4 and [Cp2ZrF{c-cis-CHCH2CH(2-NC5F4)}] with C–F bond activation. Attempts at converting this reaction sequence to a catalytic version failed due to either decomposition of the active species or multiple C–F bond substitutions by the transmetalating agent.
Published: 2020
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238. Anomalous Subdiffusion in Living Cells: Bridging the Gap Between Experiments and Realistic Models Through Collaborative Challenges

Author: Maxime Woringer, Ignacio Izeddin, Cyril Favard, Hugues Berry, Imagerie et Modélisation - Imaging and Modeling, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Hub Bioinformatique et Biostatistique - Bioinformatics and Biostatistics HUB, Sorbonne Université (SU), University of California [Berkeley], University of California, Institut Langevin - Ondes et Images (UMR7587) (IL), Sorbonne Université (SU)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Paris (UP)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria), Laboratoire d'InfoRmatique en Image et Systèmes d'information (LIRIS), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-École Centrale de Lyon (ECL), Université de Lyon-Université Lumière - Lyon 2 (UL2), Artificial Evolution and Computational Biology (BEAGLE), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire d'InfoRmatique en Image et Systèmes d'information (LIRIS), Université de Lyon-Université Lumière - Lyon 2 (UL2)-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)-École Centrale de Lyon (ECL), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), University of California [Berkeley] (UC Berkeley), University of California (UC), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Lumière - Lyon 2 (UL2)-École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), 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), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Lumière - Lyon 2 (UL2)-École Centrale de Lyon (ECL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), and Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Quantitative Biology - Subcellular Processes, Bridging (networking), Computer science, Anomalous diffusion, media_common.quotation_subject, Materials Science (miscellaneous), Biophysics, fractional Brownian motion, FOS: Physical sciences, General Physics and Astronomy, Fluorescence correlation spectroscopy, fluorescence correlation spectroscopy, diffusion in cells, [SDV.BC]Life Sciences [q-bio]/Cellular Biology, continuous-time random walks, Machine learning, computer.software_genre, Quantitative Biology - Quantitative Methods, 01 natural sciences, 0103 physical sciences, Analysis software, Physics - Biological Physics, Diffusion (business), Physical and Theoretical Chemistry, 010306 general physics, Function (engineering), Subcellular Processes (q-bio.SC), Quantitative Methods (q-bio.QM), Mathematical Physics, media_common, business.industry, lcsh:QC1-999, [SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biophysics, Biological Physics (physics.bio-ph), Single-particle tracking, FOS: Biological sciences, Simulated data, single-particle tracking, Artificial intelligence, business, computer, lcsh:Physics
Abstract: The life of a cell is governed by highly dynamical microscopic processes. Two notable examples are the diffusion of membrane receptors and the kinetics of transcription factors governing the rates of gene expression. Different fluorescence imaging techniques have emerged to study molecular dynamics. Among them, fluorescence correlation spectroscopy (FCS) and single-particle tracking (SPT) have proven to be instrumental to our understanding of cell dynamics and function. The analysis of SPT and FCS is an ongoing effort, and despite decades of work, much progress remains to be done. In this paper, we give a quick overview of the existing techniques used to analyze anomalous diffusion in cells and propose a collaborative challenge to foster the development of state-of-the-art analysis algorithms. We propose to provide labelled (training) and unlabelled (evaluation) simulated data to competitors all over the world in an open and fair challenge. The goal is to offer unified data benchmarks based on biologically-relevant metrics in order to compare the diffusion analysis software available for the community., 10 pages, 1 figure
Published: 2020
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239. Performance analysis of UFMC waveform in graded index fiber for 5G communications and beyond

Author: Iyad Dayoub, Kyunghwan Oh, Faouzi Bahloul, Mahdi Kasmi, Sofien Mhatli, SERCOM Laboratory, Université de Carthage - University of Carthage, Institut d’Électronique, de Microélectronique et de Nanotechnologie - Département Opto-Acousto-Électronique - UMR 8520 (IEMN-DOAE), 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)-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), COMmunications NUMériques - IEMN (COMNUM - 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 d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France), Institut National des Sciences Appliquées (INSA), INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France)-Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA)-Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA)-INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France)-Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA)-Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Institut d’Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520 (IEMN), Ecole Centrale de 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), Ecole Centrale de 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)-Ecole Centrale de 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)-INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France)-Institut d’Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520 (IEMN), Ecole Centrale de 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)-Ecole Centrale de 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)-INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France), and Yonsei University
Subjects: Orthogonal frequency-division multiplexing, Radio-over-fiber, 02 engineering and technology, 01 natural sciences, Graded-index fiber, [INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI], 010309 optics, [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], [SPI]Engineering Sciences [physics], Optics, Radio over fiber, 0103 physical sciences, Electronic engineering, Waveform, [INFO]Computer Science [cs], Multimode fiber, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, Universal filtered multi-carrier, ComputingMilieux_MISCELLANEOUS, Mathematics, Multi-mode optical fiber, business.industry, 021001 nanoscience & nanotechnology, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, [SPI.TRON]Engineering Sciences [physics]/Electronics, Q factor, Out-of-band management, Bit error rate, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, 0210 nano-technology, business, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, 5G
Abstract: International audience; For the first time, we demonstrate in this paper an intensity-modulation direct-detection (IMDD) universal filtered multi-carrier (UFMC) system through several hundred meters of multimode fiber (MMF) that can be adopted for 5G communications and beyond. The proposed system is simulated and evaluated in terms of bit error rate (BER), Q factor, out of band (OOB) emission and Peak-to-Average Power Ratio (PAPR), at a data rate of 10 Gb/s. It is shown that filtering used with UFMC reduces the OOB radiation by 40 dB compared to orthogonal frequency division multiplexing (OFDM). Moreover, we prove that UFMC gives lower values of BER than OFDM, and even if the PAPR ratio of UFMC is higher than OFDM, the gap remains small. The results also show that using a Volterra equalizer with increasing taps enables to obtain acceptable performance through the MMF in terms of BER, even with high number of excited mode groups.
Published: 2020
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240. An optical in-situ tool for visualizing and understanding wetting dynamics in membrane distillation

Author: Paul Jacob, Corinne Cabassud, Baptiste Dejean, Stéphanie Laborie, Toulouse Biotechnology Institute (TBI), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), ANR-14-CE04-0008,WETMEM,Nouvelles membranes et outils pour une meilleure compréhension, modélisation et contrôle du mouillage de pores en distillation membranaire pour le dessalement des eaux(2014), Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), UMR TBI, CNRS, INRA, INSA, Université de Toulouse, French National Research Agency (ANR) [ANR-14-CE04-0008], and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
Subjects: Materials science, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, Scanning electron microscope, membrane distillation, Filtration and Separation, 02 engineering and technology, 010402 general chemistry, Membrane distillation, 01 natural sciences, Biochemistry, microscopie électronique à balayage, [SPI]Engineering Sciences [physics], TRACER, tensioactif, General Materials Science, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Physical and Theoretical Chemistry, Spectroscopy, optical tool, transmission lumineuse, wetting, in situ, Laminar flow, 021001 nanoscience & nanotechnology, 0104 chemical sciences, in-situ detection, Membrane, [CHIM.POLY]Chemical Sciences/Polymers, Chemical engineering, SEM, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Wetting, 0210 nano-technology, Dispersion (chemistry)
Abstract: This paper describes the development of a new optical tool to detect in-situ wetting in membrane distillation. The principle of the detection tool is based on the phenomenon of light transmission. A dedicated experimental setup was developed. The proof of concept of this optical tool is validated using in parallel the Detection of Dissolved Tracer Intrusion (DDTI) method that was previously developed, and which is based on the detection of remaining salt traces in wetted pores by scanning electron microscopy and x-ray dispersion spectroscopy. The in-situ tool was used in standard operating conditions (feed temperature 40 °C, laminar flow and vacuum pressure 6 kPa) for vacuum membrane distillation with deionized water, a synthetic saline solution, and seawaters. Controlled wetting was then induced by adding a surfactant in the feed after 30 min of operation and wetting dynamics could be effectively visualized. Additionally, the scalability (macro and mesoscales) of this tool was verified and wetting was visualized at different locations on the membrane surface and compared with the wetting observations made at a global scale. A definition of pore wetting is also proposed.
Published: 2020
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241. Inferring the one-electron reduced density matrix of molecular crystals from experimental data sets through semidefinite programming

Author: Jean Michel Gillet, Benjamin De Bruyne, CentraleSupélec, Laboratoire Structures, Propriétés et Modélisation des solides (SPMS), and Institut de Chimie du CNRS (INC)-CentraleSupélec-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Semidefinite programming, [PHYS]Physics [physics], Work (thermodynamics), Scattering, Ab initio, Experimental data, 010403 inorganic & nuclear chemistry, Condensed Matter Physics, 01 natural sciences, Biochemistry, 0104 chemical sciences, Inorganic Chemistry, Structural Biology, Ab initio quantum chemistry methods, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], General Materials Science, Statistical physics, Limit (mathematics), Physical and Theoretical Chemistry, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], Quantum, Mathematics
Abstract: Constructing a quantum description of crystals from scattering experiments is of great significance to explain their macroscopic properties and to evaluate the pertinence of theoretical ab initio models. While reconstruction methods of the one-electron reduced density matrix have already been proposed, they are usually tied to strong assumptions that limit and may introduce bias in the model. The goal of this paper is to infer a one-electron reduced density matrix (1-RDM) with minimal assumptions. It has been found that the mathematical framework of semidefinite programming can achieve this goal. Additionally, it conveniently addresses the nontrivial constraints on the 1-RDM which were major hindrances for the existing models. The framework established in this work can be used as a reference to interpret experimental results. This method has been applied to the crystal of dry ice and provides very satisfactory results when compared with periodic ab initio calculations.
Published: 2020
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242. Sulfamethazine degradation by heterogeneous photocatalysis with ZnO immobilized on a glass plate using the heat attachment method and its impact on the biodegradability

Author: Taous Aissani, Abdeltif Amrane, Florence Fourcad, Farouk Boudrahem, Lamia Yahia Cherif, Idris Yahiaoui, Farida Aissani-Benissad, Université Abderrahmane Mira [Béjaïa], Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Materials science, Central composite design, 010405 organic chemistry, Photocatalytic process, Analytical chemistry, Immobilized ZnO, Sulfamethazine, [CHIM.CATA]Chemical Sciences/Catalysis, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Volumetric flow rate, Adsorption, Yield (chemistry), Photocatalysis, Degradation (geology), Physical and Theoretical Chemistry, Fourier transform infrared spectroscopy
Abstract: International audience; In this paper, the degradation of sulfamethazine (SMT) was performed using of photocatalytic process in the presence of ZnO catalyst immobilized on glass plate (on ZnO/glass plate) under UV light. The ZnO/glass plate was characterized by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectra; the results of the characterization demonstrated that the properties of ZnO/glass plate were maintained unmodified. The adsorption and the photolysis tests revealed the absence of adsorption of SMT onto ZnO/glass plate and the absence of direct photolysis of SMT. The effect of the initial solution pH, the flow rate and the initial concentration of SMT on the photocatalytic process was studied and optimized by using central composite design (CCD). The model equation obtained led to a classification of these parameters based on their level of significance. The results suggested that the most influential factor was the initial concentration of SMT (x(2)), which had the strongest effect on the response (- 11.6) and the negative sign of the coefficient suggested that the degradation of SMT decreased for increasing initial SMT concentration. It was followed by the flow rate with positive effect on the yield of SMT degradation (+ 2.06). The model also demonstrated the absence of pH effect in the studied interval and that the strongest interaction was between the pH and the flow rate. The kinetic of degradation of the SMT can be described by a pseudo-first order kinetic model for 10 and 50 mg/L of SMT; while the kinetic of degradation was described by a pseudo-second-order kinetic model for the highest initial concentration, [SMT](0) = 100 mg/L. The optimal values of the solution pH, the flow rate and the initial concentration of SMT were 6, 0.56 L/min and 11 mg/L. Under these conditions the removal efficiency of SMT was 96% and the BOD5/COD ratio increased from 0 to 0.20 after 5 h of irradiation time.
Published: 2020
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243. Core–Shell Nanocuboid Dimers with Nanometric Gaps

Author: Joachim R. Krenn, Viktor Kapetanovic, Matthieu Bugnet, Leïla Boubekeur-Lecaque, Iman Ragheb, Andreas Hohenau, Georges Lévi, Israa Haidar, Guillaume Radtke, Gianluigi A. Botton, Markus K. Krug, Nordin Félidj, Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS (UMR_7086)), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), 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), 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), and Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: 0303 health sciences, Materials science, Physics::Optics, Nanotechnology, 02 engineering and technology, 021001 nanoscience & nanotechnology, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Core shell, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, 03 medical and health sciences, General Energy, Physics::Atomic and Molecular Clusters, Molecule, Physical and Theoretical Chemistry, 0210 nano-technology, Plasmon, 030304 developmental biology
Abstract: International audience; Nanometric gaps in plasmonic structures can lead to huge optical near fields and, related, to strongly enhanced interaction of molecules and light. Nanocavities formed by sphere-on-film or cube-on-film systems were recently established as promising systems, eventually reaching the strong coupling regime. However, such structures are limited with respect to being bound to a surface and by having no means of adjusting the resonance wavelength to the requirements of arbitrary analytes, independent of the gap width. We suggest and investigate in this paper silver−gold compound nanocuboid dimers in colloidal solution as potential structures to mitigate both limitations. We analyze the dimers' plasmonic properties by a combination of optical spectroscopy, electron energy loss spectroscopy, and numerical simulations, focusing on the longitudinal dimer geometry and the dominant light-coupled plasmon mode. We then calculate optical field enhancements under light and electron excitation to assess the cuboid dimer's potential in sensing and spectroscopy applications.
Published: 2020
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244. Toward a simple, generic, and rapid simulation of the drying of solid foods

Author: Emmanuel Bernuau, Hedi Romdhana, Francis Courtois, Daniel Goujot, Ingénierie, Procédés, Aliments (GENIAL), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Qualisud - Pôle de La Réunion (Qualisud Réunion), Démarche intégrée pour l'obtention d'aliments de qualité (UMR Qualisud), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de La Réunion (UR)-Université de Montpellier (UM)-Avignon Université (AU)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université Montpellier 1 (UM1)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de La Réunion (UR)-Université de Montpellier (UM)-Avignon Université (AU)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université Montpellier 1 (UM1)
Subjects: General Chemical Engineering, compartment models, Finite difference, mathematical modeling, 04 agricultural and veterinary sciences, 02 engineering and technology, 040401 food science, Drying process, [SPI]Engineering Sciences [physics], 0404 agricultural biotechnology, 020401 chemical engineering, Solid food, Order (business), Simple (abstract algebra), heat and mass transfers, Applied mathematics, 0204 chemical engineering, Physical and Theoretical Chemistry, optimization, Mathematics
Abstract: International audience; In order to simulate the drying of foods, calculations based on finite differences, elements, or volumes are extremely time-consuming, particularly when embedded in an optimization procedure. Such models, involving coupled heat and mass transfers and nonlinear properties and boundaries, give rise to slow simulations. This paper proposes a new method concerning the slab, cylindrical, and spherical geometries. This method gives results equivalent to those of the finite volume method but is more rapid by an order of magnitude. The method is based on an optimized 3-compartment model whose parameters are linked to physically meaningful food properties.
Published: 2019
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245. Isomer-sensitive characterization of low temperature oxidation reaction products by coupling a jet-stirred reactor to an electron/ion coincidence spectrometer: case of n-pentane

Author: Pilippe Arnoux, Guillaume Vanhove, Jérémy Bourgalais, Zied Gouid, Olivier Herbinet, Laurent Nahon, Luc-Sy Tran, Gustavo A. Garcia, Zhandong Wang, Frédérique Battin-Leclerc, Majdi Hochlaf, IMPEC - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-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), Laboratoire Réactions et Génie des Procédés (LRGP), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Ligne DESIRS [Saint Aubin], Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), National Synchrotron Radiation Laboratory (NSRL), University of Science and Technology of China [Hefei] (USTC), Physicochimie des Processus de Combustion et de l’Atmosphère - UMR 8522 (PC2A), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Synchrotron Soleil - Ligne DESIRS, Université de Lille, CNRS, Physicochimie des Processus de Combustion et de l’Atmosphère - UMR 8522 [PC2A], PLANETO - LATMOS, 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), European Project: 636829,H2020,ERC-2014-STG,PRIMCHEM(2015), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)
Subjects: Materials science, Spectrometer, Analytical chemistry, General Physics and Astronomy, 02 engineering and technology, Photoionization, 010402 general chemistry, 021001 nanoscience & nanotechnology, Mass spectrometry, Mole fraction, 01 natural sciences, 0104 chemical sciences, Ion, Pentane, chemistry.chemical_compound, chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Mass spectrum, Physical and Theoretical Chemistry, Ionization energy, 0210 nano-technology
Abstract: Through the use of tunable vacuum ultraviolet light generated by the DESIRS VUV synchrotron beamline, a jet-stirred reactor was coupled for the first time to an advanced photoionization mass spectrometer based upon a double imaging PhotoElectron PhotoIon COincidence (i2PEPICO) scheme. This new coupling was used to investigate the low-temperature oxidation of n-pentane, a prototype molecule for gasoline or diesel fuels. Experiments were performed under quasi-atmospheric pressure (1.1 bar) with a residence time of 3 s for two equivalence ratios (1/3 and 0.5) with a fuel initial mole fraction of 0.01. The measured time-of-flight mass spectra are in good agreement with those previously obtained with other photoionization mass spectrometers and, like those previous ones, display several m/z peaks for which the related species assignation is ambiguous. This paper shows how the analysis of the coincident mass-tagged Threshold PhotoElectron Spectra (TPES) together with first principle computations, consisting of the determination of the adiabatic ionization energies and the spectra of some products, may assist products’ identification. The results mostly confirm those previously obtained by photoionization mass spectrometry and gas chromatography, but also allow a more accurate estimation of the 1-pentene/2-pentene mole fraction ratio. Our data also indicate a higher formation of acetone and methyl ethyl ketone than what is predicted by current models, as well as the presence of products that were not previously taken into account, such as methoxyacetylene, methyl vinyl ketone or furanone. The formation of three, four and five membered ring cyclic ethers is confirmed along with linear ketones: 2- and 3-pentanone. A significant general trend in indicating higher amounts of ketones than are indicated by gas chromatography is noted. Finally, TPES of alkenylhydroperoxides are also provided for the first time and constrains on the isomers identification are provided. 22;3
Published: 2019
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246. Combined SERS/DFT studies of push–pull chromophore self-assembled monolayers: insights into their surface orientation

Author: Philippe Marsal, C. Praveen, Lionel Patrone, B. Grenier, J. C. Valmalette, Jean-Manuel Raimundo, Virginie Gadenne, Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Center for Applicable Mathematics [Bangalore] (TIFR-CAM), Tata Institute for Fundamental Research (TIFR), Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), and Tata Institute of Fundamental Research [Bombay] (TIFR)
Subjects: Surface (mathematics), Materials science, General Physics and Astronomy, Nanotechnology, Self-assembled monolayer, 02 engineering and technology, Chromophore, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, symbols.namesake, Terthiophene, chemistry, Perpendicular, symbols, Molecule, Physical and Theoretical Chemistry, Solvent effects, 0210 nano-technology, Raman spectroscopy
Abstract: International audience; Having clear and deep information on the surface/interface of deposited molecules is of crucial importance for the development of efficient optoelectronic devices. This paper reports on a joint experimental/theoretical approach based on Raman spectroscopy in order to provide information on the orientation of deposited push-pull chromophores onto a gold surface. In addition, several parameters can strongly control or impede the orientation of such molecules on the surface such as: the molecular structure, the surface itself, the method of deposition and the solvents used. From this approach, additional information has been highlighted such as perpendicularly depositing the molecule on the surface, the bithiophene compounds displaying more solvent effects compared to terthiophene molecules and so on. According to the results, the joint SERS/DFT study proves to be an effective tool for probing the arrangement of push-pull chromophores and selecting right experimental conditions to tune the surface properties.
Published: 2019
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247. Photoselective MLCT to d-d pathways for light-induced excited spin state trapping

Author: Eric Collet, Serhane Zerdane, Marco Cammarata, Marie-Laure Boillot, O. Iasco, Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Région Bretagne (Grant No. ARED 8925/XFELMAT), ANR-13-BS04-0002,FEMTOMAT,Etude femtoseconde rayons X et optique de la dynamique ultrarapide de photocommutation de matériaux moléculaires magnétiques(2013), ANR-15-CE32-0004,BioXFEL,Caractérisation d'états intermédiaires de protéines fluorescentes en utilisant des lasers à électrons libres X et les spectroscopies UV-visible et infrarouge ultra-rapides(2015), and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Ligand field theory, [PHYS]Physics [physics], Materials science, 010304 chemical physics, Spin states, General Physics and Astronomy, 010402 general chemistry, 01 natural sciences, Molecular physics, LIESST, 0104 chemical sciences, Excited state, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [CHIM.COOR]Chemical Sciences/Coordination chemistry, Singlet state, Physical and Theoretical Chemistry, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], Spin (physics), Spectroscopy, Excitation, ComputingMilieux_MISCELLANEOUS
Abstract: We use femtosecond optical pump-probe spectroscopy to study the Light Induced Excited Spin State Trapping (LIESST) dynamics in an FeII spin-crossover material. In these systems, LIESST derives from fast molecular switching induced by light from low (LS, S = 0) to high spin (HS, S = 2) states, as reported for molecules in solution as well as in the solid state. Since the direct LS-to-HS conversion is forbidden by selection rules, the switching dynamics involves intermediate electronic states such as metal-to-ligand charge transfer (MLCT) or ligand-field excited states of singlet or triplet nature. In addition, the HS state is structurally trapped by the elongation of the metal-ligand bond, which is accompanied by the coherent activation and damping of the molecular breathing mode. The ultrafast LIESST dynamics was mainly investigated in FeN6 ligand field systems with almost octahedral symmetry, under MLCT excitation. Our recent study on the FeII(pap-5NO2)2 spin-crossover material, with a FeIIN4O2 ligand field of C2 symmetry, has shown that in addition to MLCT bands, optical excitation, through quite intense and low-energy shifted d-d bands, can also drive LIESST. Compared to MLCT, d-d excitation involves shorter-lived intermediates, drives faster LS-to-HS switching, and enhances the coherent structural dynamics. In this paper, we present an ultrafast study of the pump wavelength dependence of LIESST and we evidence a photoselective crossover from the MLCT to the d-d pathways.
Published: 2019
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248. Thermal conductivity prediction of nanofluids containing CuO nanoparticles by using correlation and artificial neural network

Author: Amir Hossein Raffiee, Mostafa Safdari Shadloo, Mohammad Alhuyi Nazari, Ali Komeilibirjandi, Akbar Maleki, Complexe de recherche interprofessionnel en aérothermochimie (CORIA), Centre National de la Recherche Scientifique (CNRS)-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)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), and Normandie Université (NU)
Subjects: Materials science, Artificial neural network, Nanoparticle, Thermodynamics, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, 010406 physical chemistry, 0104 chemical sciences, Cuo nanoparticles, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Correlation, Thermal conductivity, Nanofluid, Thermal, Heat transfer, Physical and Theoretical Chemistry, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS
Abstract: Nanofluids are employed in different thermal devices due to their enhanced thermophysical features which lead to noticeable heat transfer augmentation. One of the major reasons of the heat transfer improvement by using the nanofluids is their increased thermal conductivity. Several methods have been applied to estimate this property of nanofluids such as correlations and artificial neural networks (ANNs). In the present paper, group method of data handling (GMDH) and a mathematical correlation are proposed for forecasting the thermal conductivity of nanofluids containing CuO nanoparticles. The inputs of the both models are the base fluids’ thermal conductivities, concentration, temperature and nanoparticle dimension. Comparison of the forecasted data by these two approaches revealed more favorable performance of GMDH. The values of R-squared in the cases where polynomial and ANN were utilized were 0.9862 and 0.9996, respectively. Moreover, the average absolute relative deviation values were 5.25% and 0.881% for the indicated methods, respectively. According to these statistical values, it is concluded that employing the ANN-based regression leads to more confident model for forecasting the TC of the nanofluids containing CuO nanoparticles.
Published: 2019
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249. X-ray constrained spin-coupled technique: theoretical details and further assessment of the method

Author: Alessandro Genoni, Giovanni Macetti, Maurizio Sironi, Stefano Pieraccini, Davide Franchini, Laboratoire de Physique et Chimie Théoriques (LPCT), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Chimica [Milano, Italy], Università degli Studi di Milano [Milano] (UNIMI), Istituto di Scienze e Tecnologie Molecolari = Institute of Molecular Science and Technologies (ISTM-CNR [Perugia - Milano]), Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali, ANR-17-CE29-0005,QuMacroRef,De nouvelles stratégies efficaces basées sur la mécanique quantique pour l'affinement de structures cristallographiques de macromolécules à haute résolution(2017), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), and Università degli studi di Milano [Milano]
Subjects: Physics, 010304 chemical physics, Basis (linear algebra), Computer Science::Information Retrieval, 010403 inorganic & nuclear chemistry, Condensed Matter Physics, 01 natural sciences, Biochemistry, 0104 chemical sciences, Inorganic Chemistry, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Atomic orbital, Structural Biology, 0103 physical sciences, Convergence (routing), [CHIM.CRIS]Chemical Sciences/Cristallography, A priori and a posteriori, General Materials Science, Valence bond theory, Molecular orbital, Statistical physics, Physical and Theoretical Chemistry, Wave function, ComputingMilieux_MISCELLANEOUS, Ansatz
Abstract: One of the well-established methods of modern quantum crystallography is undoubtedly the X-ray constrained wavefunction (XCW) approach, a technique that enables the determination of wavefunctions which not only minimize the energy of the system under examination, but also reproduce experimental X-ray diffraction data within the limit of the experimental errors. Initially proposed in the framework of the Hartree–Fock method, the strategy has been gradually extended to other techniques of quantum chemistry, but always remaining limited to a single-determinant ansatz for the wavefunction to extract. This limitation has been recently overcome through the development of the novel X-ray constrained spin-coupled (XCSC) approach [Genoni et al. (2018). Chem. Eur. J. 24, 15507–15511] which merges the XCW philosophy with the traditional spin-coupled strategy of valence bond theory. The main advantage of this new technique is the possibility of extracting traditional chemical descriptors (e.g. resonance structure weights) compatible with the experimental diffraction measurements, without the need to introduce information a priori or perform analyses a posteriori. This paper provides a detailed theoretical derivation of the fundamental equations at the basis of the XCSC method and also introduces a further advancement of its original version, mainly consisting in the use of molecular orbitals resulting from XCW calculations at the Hartree–Fock level to describe the inactive electrons in the XCSC computations. Furthermore, extensive test calculations, which have been performed by exploiting high-resolution X-ray diffraction data for salicylic acid and by adopting different basis sets, are presented and discussed. The computational tests have shown that the new technique does not suffer from particular convergence problems. Moreover, all the XCSC calculations provided resonance structure weights, spin-coupled orbitals and global electron densities slightly different from those resulting from the corresponding unconstrained computations. These discrepancies can be ascribed to the capability of the novel strategy to capture the information intrinsically contained in the experimental data used as external constraints.
Published: 2019
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250. Flame Retardant Epoxy Composites on the Road of Innovation: An Analysis with Flame Retardancy Index for Future Development

Author: Vahabi, Henri, Movahedifar, Elnaz, Saeb, Mohammad Reza, Thomas, Sabu, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), and CentraleSupélec-Université de Lorraine (UL)
Subjects: Materials science, Injury control, Accident prevention, Pharmaceutical Science, Poison control, Review, 02 engineering and technology, Calorimetry, 010402 general chemistry, 01 natural sciences, epoxy, Analytical Chemistry, lcsh:QD241-441, lcsh:Organic chemistry, Drug Discovery, Physical and Theoretical Chemistry, Composite material, ComputingMilieux_MISCELLANEOUS, Flame Retardants, Flammability, Epoxy Resins, Organic Chemistry, Phosphorus, cone calorimetry, Epoxy, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, [CHIM.POLY]Chemical Sciences/Polymers, Chemistry (miscellaneous), visual_art, Thermogravimetry, visual_art.visual_art_medium, Molecular Medicine, fire retardancy, 0210 nano-technology, flame retardancy index (fri), Fire retardant
Abstract: Nowadays, epoxy composites are elements of engineering materials and systems. Although they are known as versatile materials, epoxy resins suffer from high flammability. In this sense, flame retardancy analysis has been recognized as an undeniable requirement for developing future generations of epoxy-based systems. A considerable proportion of the literature on epoxy composites has been devoted to the use of phosphorus-based additives. Nevertheless, innovative flame retardants have coincidentally been under investigation to meet market requirements. This review paper attempts to give an overview of the research on flame retardant epoxy composites by classification of literature in terms of phosphorus (P), non-phosphorus (NP), and combinations of P/NP additives. A comprehensive set of data on cone calorimetry measurements applied on P-, NP-, and P/NP-incorporated epoxy systems was collected and treated. The performance of epoxy composites was qualitatively discussed as Poor, Good, and Excellent cases identified and distinguished by the use of the universal Flame Retardancy Index (FRI). Moreover, evaluations were rechecked by considering the UL-94 test data in four groups as V0, V1, V2, and nonrated (NR). The dimensionless FRI allowed for comparison between flame retardancy performances of epoxy composites. The results of this survey can pave the way for future innovations in developing flame-retardant additives for epoxy.
Published: 2019
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