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2. Microcristaux organiques : préparation contrôlée en vue d'applications dans les domaines de l'optique et de la pharmacologie

Author

Abyan, M., Edmond, A., Rodrigues, Fernanda, Fery-Forgues, Suzanne, 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 de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Institut de Chimie de Toulouse (ICT), 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), 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)

Subjects
stomatognathic diseases, InformationSystems_MODELSANDPRINCIPLES, ComputingMilieux_THECOMPUTINGPROFESSION, GeneralLiterature_INTRODUCTORYANDSURVEY, ComputingMilieux_COMPUTERSANDEDUCATION, [CHIM.OTHE]Chemical Sciences/Other
Abstract

communication orale

Published
2006

3. Effet des polymères sur la croissance etles propriétés optiques de microcristaux oragniques fluorescents

Author

Abyan, M., Fery-Forgues, Suzanne, 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 de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Institut de Chimie de Toulouse (ICT), 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), 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)

Subjects
stomatognathic diseases, InformationSystems_MODELSANDPRINCIPLES, ComputingMilieux_THECOMPUTINGPROFESSION, GeneralLiterature_INTRODUCTORYANDSURVEY, ComputingMilieux_COMPUTERSANDEDUCATION, [CHIM.OTHE]Chemical Sciences/Other
Abstract

communication orale

Published
2005

4. Effet des polymères sur la croissance et les propriétés optiques de microcristaux oraniques fluorescents

Author

Abyan, M., Fery-Forgues, Suzanne, Interactions moléculaires et réactivité chimique et photochimique (IMRCP), 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), 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), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
stomatognathic diseases, InformationSystems_MODELSANDPRINCIPLES, ComputingMilieux_THECOMPUTINGPROFESSION, GeneralLiterature_INTRODUCTORYANDSURVEY, ComputingMilieux_COMPUTERSANDEDUCATION, [CHIM.OTHE]Chemical Sciences/Other
Abstract

communication orale

Published
2005

5. Préparation contrôlée et étude des propriétés optiques de microcristaux organiques fluorescents

Author

Abyan, M., Fery-Forgues, Suzanne, 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 de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Institut de Chimie de Toulouse (ICT), 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), 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)

Subjects
stomatognathic diseases, InformationSystems_MODELSANDPRINCIPLES, ComputingMilieux_THECOMPUTINGPROFESSION, GeneralLiterature_INTRODUCTORYANDSURVEY, ComputingMilieux_COMPUTERSANDEDUCATION, [CHIM.OTHE]Chemical Sciences/Other
Abstract

communication orale

Published
2005

6. Microcristaux d'un colorant organique fluorescent : contrôle de la morphologie et approche des propriétés optiques

Author

Abyan, M., Birla, L., Bertorelle, Franck, Fery-Forgues, Suzanne, Rodrigues, Fernanda, Interactions moléculaires et réactivité chimique et photochimique (IMRCP), 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), 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), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
stomatognathic diseases, InformationSystems_MODELSANDPRINCIPLES, ComputingMilieux_THECOMPUTINGPROFESSION, GeneralLiterature_INTRODUCTORYANDSURVEY, ComputingMilieux_COMPUTERSANDEDUCATION, [CHIM.OTHE]Chemical Sciences/Other
Abstract

communication orale

Published
2005

9. Use of Linear Polymers To Control the Preparation of Luminescent Organic Microcrystals

Author

Abyan, M., Bertorelle, F., and Fery-Forgues, S.

Abstract

Microcrystals of an organic fluorescent dye, 4-octylamino-7-nitrobenz-2-oxa-1,3-diazole, were generated using the reprecipitation method, which is a solvent exchange process. In the presence of polymers, namely, poly(acrylic acid), molecular weight 5100 g mol-1 and 15 000 g mol-1, and poly(acrylic acid-co-maleic acid), average molecular weight about 50 000 g mol-1, used as their sodium salts, the reprecipitation process was strongly accelerated. The reprecipitation kinetics was monitored by UV/vis absorption spectroscopy and revealed a three-step mechanism, each step being influenced by the polymer. The size and shape of the microcrystals were analyzed by fluorescence microscopy. The microcrystals obtained in the presence of polymers were smaller and more regular than those prepared in water alone and were not agglomerated. When the polymer was placed in the reprecipitation medium before introducing the dye solution, the microcrystals displayed a rectangular shape. When the polymer was introduced 20 min after the beginning of the reprecipitation process, intricately structured flowerlike microcrystals were observed. Microanalysis revealed that the microcrystals contained noticeable amounts of polymer. The measurement of the surface electric ζ potential suggested that a proportion of the polymer was present at the microcrystal surface. This work gives a thorough insight into a field where trials have until now been performed in an empirical way. It opens new perspectives to produce low-cost organic microcrystals, potentially useful in optics or pharmaceutical sciences.

Published
2005

10. One-pot noninjection route to CdS quantum dots via hydrothermal synthesis.

Author

Aboulaich A, Billaud D, Abyan M, Balan L, Gaumet JJ, Medjadhi G, Ghanbaja J, and Schneider R

Abstract

Water-dispersible CdS quantum dots (QDs) emitting from 510 to 650 nm were synthesized in a simple one-pot noninjection hydrothermal route using cadmium chloride, thiourea, and 3-mercaptopropionic acid (MPA) as starting materials. All these chemicals were loaded at room temperature in a Teflon sealed tube and the reaction mixture heated at 100 °C. The effects of CdCl(2)/thiourea/MPA feed molar ratios, pH, and concentrations of precursors affecting the growth of the CdS QDs, was monitored via the temporal evolution of the optical properties of the CdS nanocrystals. High concentration of precursors and high MPA/Cd feed molar ratios were found to lead to an increase in the diameter of the resulting CdS nanocrystals and of the trap state emission of the dots. The combination of moderate pH value, low concentration of precursors and slow growth rate plays the crucial role in the good optical properties of the obtained CdS nanocrystals. The highest photoluminescence achieved for CdS@MPA QDs of average size 3.5 nm was 20%. As prepared colloids show rather narrow particle size distribution, although all reactants were mixed at room temperature. CdS@MPA QDs were characterized by UV-vis and photoluminescence spectroscopy, powder X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectrometry and MALDI TOF mass spectrometry. This noninjection one-pot approach features easy handling and large-scale production with excellent synthetic reproducibility. Surface passivation of CdS@MPA cores by a wider bandgap material, ZnS, led to enhanced luminescence intensity. CdS@MPA and CdS/ZnS@MPA QDs exhibit high photochemical stability and hold a good potential to be applied in optoelectronic devices and biological applications.

Published
2012
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11. In situ characterization by SAXS of concentration polarization layers during cross-flow ultrafiltration of Laponite dispersions.

Author

Pignon F, Abyan M, David C, Magnin A, and Sztucki M

Subjects
Kinetics, Rheology, Scattering, Small Angle, Ultrafiltration methods, X-Ray Diffraction methods
Abstract

The structural organization inside the concentration polarization layer during cross-flow membrane separation process of Laponite colloidal dispersions has been characterized for the first time by in situ time-resolved small-angle X-ray scattering (SAXS). Thanks to the development of new "SAXS cross-flow filtration cells", concentration profiles have been measured as a function of the distance z from the membrane surface with 50 μm accuracy and linked to the permeation flux, cross-flow, and transmembrane pressure registered simultaneously. Different rheological behaviors (thixotropic gel with a yield stress or shear thinning sol) have been explored by controlling the mutual interactions between the particles as a result on the addition of peptizer. The structural reversibility of the concentration polarization layer has been demonstrated being in agreement with permeation flux measurements. These observations were related to structure of the dispersions under flow and their osmotic pressure., (© 2011 American Chemical Society)

Published
2012
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12. Suspensions of organic microcrystals produced in the presence of polymers: diversity of UV/Vis absorption and fluorescence properties according to the preparation conditions.

Author

Abyan M, de Caro D, and Fery-Forgues S

Subjects
Crystallization, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Molecular Structure, Spectrophotometry, X-Ray Diffraction, Organic Chemicals chemistry, Polymers chemistry
Abstract

Free-standing microcrystals of an organic fluorescent dye, specifically, 4-n-octylamino-7-nitrobenz-2-oxa-1,3-diazole, were prepared using a solvent-exchange process at room temperature, in the presence of polymers used as additives. Parameters such as the dye concentration, the nature and concentration of the polymer, and the pH of the solution were varied. Six samples of microcrystals were therefore obtained and characterized by fluorescence microscopy and by electron microscopy (TEM and SEM). They differed by their content in microcrystals, the shape and size of which depends strongly on experimental conditions. Curiously, the UV/vis absorption spectra of the microcrystal suspensions were very different from one sample to another. As a result the emission spectra were also varied. The diversity of the optical response obtained was attributed to the presence of several dye populations in the microcrystal suspensions. A distinction was made between the intrinsic spectral properties of the microcrystals and artifacts due to the presence of the additives.

Published
2009
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13. Nano- and microparticles of organic fluorescent dyes: self-organization and optical properties.

Author

Fery-Forgues S, Abyan M, and Lamere JF

Subjects
Chemistry, Organic methods, Coumarins chemistry, Crystallization, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Microscopy, Fluorescence methods, Models, Chemical, Nanoparticles chemistry, Oxadiazoles chemistry, Solvents chemistry, Spectrometry, Fluorescence instrumentation, Fluorescent Dyes chemistry, Nanotechnology methods, Spectrometry, Fluorescence methods
Abstract

Organic nanostructured materials are of increasing interest for applications in the fields of bioanalysis, photocatalysis, photonics, and organic light-emitting diodes. However, their preparation is still difficult to control and their optical properties are inadequately known. A solvent-exchange process called the "reprecipitation method" was used here to prepare nano- and microcrystals from fluorescent dyes belonging, for example, to the coumarin and nitrobenzoxadiazole (NBD) series. Typically, the dyes were dissolved in a hydrophilic organic solvent and then suddenly placed in an aqueous environment, where they spontaneously produce molecular assemblies. According to the self-association properties of the dyes and to the experimental conditions used, the nano- and microcrystals obtained exhibited different sizes and shapes, as observed by fluorescence and electron microscopy. In some cases, the crystal habit was controlled by adding some additives to the reprecipitation medium. The overall optical properties of the free-standing particles in suspension were generally quite close to those of the dissolved dyes. However, strong distortions of the absorption and emission spectra were observed for crystals grown in the presence of ionic additives. Under the fluorescence microscope, individual microcrystals may show peculiar emission characteristics, displaying bright and dark zones, or behaving like tiny optical fibers.

Published
2008
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