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Fiard M, Militon C, Sylvi L, Migeot J, Michaud E, Jézéquel R, Gilbert F, Bihannic I, Devesa J, Dirberg G, Cuny P. Uncovering potential mangrove microbial bioindicators to assess urban and agricultural pressures on Martinique island in the eastern Caribbean Sea. Sci Total Environ 2024; 928:172217. [PMID: 38583633 DOI: 10.1016/j.scitotenv.2024.172217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 04/02/2024] [Accepted: 04/02/2024] [Indexed: 04/09/2024]
Abstract
Martinique's mangroves, which cover 1.85 ha of the island (<0.1 % of the total area), are considerably vulnerable to local urban, agricultural, and industrial pollutants. Unlike for temperate ecosystems, there are limited indicators that can be used to assess the anthropogenic pressures on mangroves. This study investigated four stations on Martinique Island, with each being subject to varying anthropogenic pressures. An analysis of mangrove sediment cores approximately 18 cm in depth revealed two primary types of pressures on Martinique mangroves: (i) an enrichment in organic matter in the two stations within the highly urbanized bay of Fort-de-France and (ii) agricultural pressure observed in the four studied mangrove stations. This pressure was characterized by contamination, exceeding the regulatory thresholds, with dieldrin, total DDT, and metals (As, Cu and Ni) found in phytosanitary products. The mangroves of Martinique are subjected to varying degrees of anthropogenic pressure, but all are subjected to contamination by organochlorine pesticides. Mangroves within the bay of Fort-de-France experience notably higher pressures compared to those in the island's northern and southern regions. In these contexts, the microbial communities exhibited distinct responses. The microbial biomass and the abundance of bacteria and archaea were higher in the two less-impacted stations, while in the mangrove of Fort-de-France, various phyla typically associated with polluted environments were more prevalent. These differences in the microbiota composition led to the identification of 65 taxa, including Acanthopleuribacteraceae, Spirochaetaceae, and Pirellulaceae, that could potentially serve as indicators of an anthropogenic influence on the mangrove sediments of Martinique Island.
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Affiliation(s)
- Maud Fiard
- Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO, 13288 Marseille, France.
| | - Cécile Militon
- Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO, 13288 Marseille, France.
| | - Léa Sylvi
- Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO, 13288 Marseille, France.
| | - Jonathan Migeot
- Impact Mer consulting, expertise, and R&D firm, 20 rue Karukéra, 97200 Fort de France, Martinique/FWI, France.
| | - Emma Michaud
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, 29280 Plouzané, France.
| | - Ronan Jézéquel
- CEDRE, 715 rue Alain Colas, 29218 Brest CEDEX 2, France.
| | - Franck Gilbert
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse INP, Université Toulouse 3 - Paul Sabatier, Toulouse, France.
| | | | - Jeremy Devesa
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, 29280 Plouzané, France.
| | - Guillaume Dirberg
- Biologie des Organismes et Ecosystèmes Aquatiques (UMR 8067 BOREA) Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, IRD, UCN, UA, Rue Buffon, 75005 Paris, France.
| | - Philippe Cuny
- Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO, 13288 Marseille, France.
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Lesniewska N, Duval JFL, Caillet C, Razafitianamaharavo A, Pinheiro JP, Bihannic I, Gley R, Le Cordier H, Vyas V, Pagnout C, Sohm B, Beaussart A. Physicochemical surface properties of Chlorella vulgaris: a multiscale assessment, from electrokinetic and proton uptake descriptors to intermolecular adhesion forces. Nanoscale 2024; 16:5149-5163. [PMID: 38265106 DOI: 10.1039/d3nr04740g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Given the growing scientific and industrial interests in green microalgae, a comprehensive understanding of the forces controlling the colloidal stability of these bioparticles and their interactions with surrounding aqueous microenvironment is required. Accordingly, we addressed here the electrostatic and hydrophobic surface properties of Chlorella vulgaris from the population down to the individual cell levels. We first investigated the organisation of the electrical double layer at microalgae surfaces on the basis of electrophoresis measurements. Interpretation of the results beyond zeta-potential framework underlined the need to account for both the hydrodynamic softness of the algae cells and the heterogeneity of their interface formed with the outer electrolyte solution. We further explored the nature of the structural charge carriers at microalgae interfaces through potentiometric proton titrations. Extraction of the electrostatic descriptors of interest from such data was obscured by cell physiology processes and dependence thereof on prevailing measurement conditions, which includes light, temperature and medium salinity. As an alternative, cell electrostatics was successfully evaluated at the cellular level upon mapping the molecular interactions at stake between (positively and negatively) charged atomic force microscopy tips and algal surface via chemical force microscopy. A thorough comparison between charge-dependent tip-to-algae surface adhesion and hydrophobicity level of microalgae surface evidenced that the contribution of electrostatics to the overall interaction pattern is largest, and that the electrostatic/hydrophobic balance can be largely modulated by pH. Overall, the combination of multiscale physicochemical approaches allowed a drawing of some of the key biosurface properties that govern microalgae cell-cell and cell-surface interactions.
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Affiliation(s)
| | | | - Céline Caillet
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France.
| | | | | | | | - Renaud Gley
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France.
| | | | - Varun Vyas
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France.
| | | | - Bénédicte Sohm
- Université de Lorraine, CNRS, LIEC, F-57000, Metz, France
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Bihannic I, Gley R, Gallo L, Badura A, Razafitianamaharavo A, Beuret M, Billet D, Bojic C, Caillet C, Morlot P, Zaffino M, Jouni F, George B, Boulet P, Noûs C, Danger M, Felten V, Pagnout C, Duval JFL. Photodegradation of disposable polypropylene face masks: Physicochemical properties of debris and implications for the toxicity of mask-carried river biofilms. J Hazard Mater 2024; 465:133067. [PMID: 38039813 DOI: 10.1016/j.jhazmat.2023.133067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 11/18/2023] [Accepted: 11/21/2023] [Indexed: 12/03/2023]
Abstract
COVID-19 outbreak led to a massive dissemination of protective polypropylene (PP) face masks in the environment, posing a new environmental risk amplified by mask photodegradation and fragmentation. Masks are made up of a several kilometres long-network of fibres with diameter from a few microns to around 20 µm. After photodegradation, these fibres disintegrate, producing water dispersible debris. Electrokinetics and particle stability observations support that photodegradation increases/decreases the charge/hydrophobicity of released colloidal fragments. This change in hydrophobicity is related to the production of UV-induced carbonyl and hydroxyl reactive groups detectable after a few days of exposure. Helical content, surface roughness and specific surface area of mask fibres are not significantly impacted by photodegradation. Fragmentation of fibres makes apparent, at the newly formed surfaces, otherwise-buried additives like TiO2 nanoparticles and various organic components. Mortality of gammarids is found to increase significantly over time when fed with 3 days-UV aged masks that carry biofilms grown in river, which is due to a decreased abundance of microphytes therein. In contrast, bacteria abundance and microbial community composition remain unchanged regardless of mask degradation. Overall, this work reports physicochemical properties of pristine and photodegraded masks, and ecosystemic functions and ecotoxicity of freshwater biofilms they can carry.
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Affiliation(s)
| | - Renaud Gley
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France
| | - Lucas Gallo
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France
| | | | | | | | - David Billet
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France
| | - Clément Bojic
- Université de Lorraine, CNRS, LIEC, F-57000 Metz, France
| | - Céline Caillet
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France
| | | | - Marie Zaffino
- Université de Lorraine, CNRS, LIEC, F-57000 Metz, France
| | - Fatina Jouni
- Université de Lorraine, CNRS, LIEC, F-57000 Metz, France
| | - Béatrice George
- Université de Lorraine, INRAE, LERMAB, F-54000 Nancy, France
| | - Pascal Boulet
- Université de Lorraine, CNRS, IJL, F-54000 Nancy, France
| | | | - Michael Danger
- Université de Lorraine, CNRS, LIEC, F-57000 Metz, France
| | - Vincent Felten
- Université de Lorraine, CNRS, LIEC, F-57000 Metz, France
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Fiard M, Cuny P, Sylvi L, Hubas C, Jézéquel R, Lamy D, Walcker R, El Houssainy A, Heimbürger-Boavida LE, Robinet T, Bihannic I, Gilbert F, Michaud E, Dirberg G, Militon C. Mangrove microbiota along the urban-to-rural gradient of the Cayenne estuary (French Guiana, South America): Drivers and potential bioindicators. Sci Total Environ 2022; 807:150667. [PMID: 34599952 DOI: 10.1016/j.scitotenv.2021.150667] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 09/13/2021] [Accepted: 09/25/2021] [Indexed: 06/13/2023]
Abstract
The microbial communities inhabiting the Atlantic-East Pacific (AEP) mangroves have been poorly studied, and mostly comprise chronically polluted mangroves. In this study, we characterized changes in the structure and diversity of microbial communities of mangroves along the urban-to-rural gradient of the Cayenne estuary (French Guiana, South America) that experience low human impact. The microbial communities were assigned into 50 phyla. Proteobacteria, Chloroflexi, Acidobacteria, Bacteroidetes, and Planctomycetes were the most abundant taxa. The environmental determinants found to significantly correlated to the microbial communities at these mangroves were granulometry, dieldrin concentration, pH, and total carbon (TC) content. Furthermore, a precise analysis of the sediment highlights the existence of three types of anthropogenic pressure among the stations: (i) organic matter (OM) enrichment due to the proximity to the city and its wastewater treatment plant, (ii) dieldrin contamination, and (iii) naphthalene contamination. These forms of weak anthropogenic pressure seemed to impact the bacterial population size and microbial assemblages. A decrease in Bathyarchaeota, "Candidatus Nitrosopumilus", and Nitrospira genera was observed in mangroves subjected to OM enrichment. Mangroves polluted with organic contaminants were enriched in Desulfobacteraceae, Desulfarculaceae, and Acanthopleuribacteraceae (with dieldrin or polychlorobiphenyl contamination), and Chitinophagaceae and Geobacteraceae (with naphthalene contamination). These findings provide insights into the main environmental factors shaping microbial communities of mangroves in the AEP that experience low human impact and allow for the identification of several potential microbial bioindicators of weak anthropogenic pressure.
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Affiliation(s)
- Maud Fiard
- Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO, 13288 Marseille, France.
| | - Philippe Cuny
- Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO, 13288 Marseille, France.
| | - Léa Sylvi
- Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO, 13288 Marseille, France.
| | - Cédric Hubas
- Biologie des Organismes et Ecosystèmes Aquatiques (UMR 8067 BOREA) Muséum National D'Histoire Naturelle, CNRS, Sorbonne Université, IRD, UCN, UA, Station Marine de Concarneau, 29900 Concarneau, France.
| | | | - Dominique Lamy
- Biologie des Organismes et Ecosystèmes Aquatiques (UMR 8067 BOREA) Muséum National D'Histoire Naturelle, CNRS, Sorbonne Université, IRD, UCN, UA, Rue Buffon, 75005 Paris, France; Institute of Ecology and Environmental Sciences of Paris (iEES-Paris), Sorbonne Université, Univ Paris Est Créteil, IRD, CNRS, INRA, 4 place Jussieu, 75005 Paris, France.
| | - Romain Walcker
- Laboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, France.
| | - Amonda El Houssainy
- Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO, 13288 Marseille, France.
| | | | - Tony Robinet
- Biologie des Organismes et Ecosystèmes Aquatiques (UMR 8067 BOREA) Muséum National D'Histoire Naturelle, CNRS, Sorbonne Université, IRD, UCN, UA, Station Marine de Concarneau, 29900 Concarneau, France.
| | | | - Franck Gilbert
- Laboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, France.
| | - Emma Michaud
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, 29280 Plouzané, France.
| | - Guillaume Dirberg
- Biologie des Organismes et Ecosystèmes Aquatiques (UMR 8067 BOREA) Muséum National D'Histoire Naturelle, CNRS, Sorbonne Université, IRD, UCN, UA, Rue Buffon, 75005 Paris, France.
| | - Cécile Militon
- Aix Marseille Univ., Université de Toulon, CNRS, IRD, MIO, 13288 Marseille, France.
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Jégou C, Connan S, Bihannic I, Cérantola S, Guérard F, Stiger-Pouvreau V. Phlorotannin and Pigment Content of Native Canopy-Forming Sargassaceae Species Living in Intertidal Rockpools in Brittany (France): Any Relationship with Their Vertical Distribution and Phenology? Mar Drugs 2021; 19:504. [PMID: 34564166 PMCID: PMC8469379 DOI: 10.3390/md19090504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/30/2021] [Accepted: 09/02/2021] [Indexed: 11/16/2022] Open
Abstract
Five native Sargassaceae species from Brittany (France) living in rockpools were surveyed over time to investigate photoprotective strategies according to their tidal position. We gave evidences for the existence of a species distribution between pools along the shore, with the most dense and smallest individuals in the highest pools. Pigment contents were higher in lower pools, suggesting a photo-adaptive process by which the decreasing light irradiance toward the low shore was compensated by a high production of pigments to ensure efficient photosynthesis. Conversely, no xanthophyll cycle-related photoprotective mechanism was highlighted because high levels of zeaxanthin rarely occurred in the upper shore. Phlorotannins were not involved in photoprotection either; only some lower-shore species exhibited a seasonal trend in phlorotannin levels. The structural complexity of phlorotannins appears more to be a taxonomic than an ecological feature: Ericaria produced simple phloroglucinol while Cystoseira and Gongolaria species exhibited polymers. Consequently, tide pools could be considered as light-protected areas on the intertidal zone, in comparison with the exposed emerged substrata where photoprotective mechanisms are essential.
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Affiliation(s)
- Camille Jégou
- Laboratoire de Biotechnologie et Chimie Marine (LBCM) EA 3884, Université de Brest, 6 Rue de l’université, F-29334 Quimper, France;
| | - Solène Connan
- Laboratoire des Sciences de l’Environnement (LEMAR) UMR 6539, Université de Brest, CNRS, IRD, Ifremer, F-29280 Plouzane, France; (S.C.); (I.B.); (F.G.)
| | - Isabelle Bihannic
- Laboratoire des Sciences de l’Environnement (LEMAR) UMR 6539, Université de Brest, CNRS, IRD, Ifremer, F-29280 Plouzane, France; (S.C.); (I.B.); (F.G.)
| | | | - Fabienne Guérard
- Laboratoire des Sciences de l’Environnement (LEMAR) UMR 6539, Université de Brest, CNRS, IRD, Ifremer, F-29280 Plouzane, France; (S.C.); (I.B.); (F.G.)
| | - Valérie Stiger-Pouvreau
- Laboratoire des Sciences de l’Environnement (LEMAR) UMR 6539, Université de Brest, CNRS, IRD, Ifremer, F-29280 Plouzane, France; (S.C.); (I.B.); (F.G.)
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Pagnout C, Razafitianamaharavo A, Sohm B, Caillet C, Beaussart A, Delatour E, Bihannic I, Offroy M, Duval JFL. Osmotic stress and vesiculation as key mechanisms controlling bacterial sensitivity and resistance to TiO 2 nanoparticles. Commun Biol 2021; 4:678. [PMID: 34083706 PMCID: PMC8175758 DOI: 10.1038/s42003-021-02213-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 05/11/2021] [Indexed: 02/04/2023] Open
Abstract
Toxicity mechanisms of metal oxide nanoparticles towards bacteria and underlying roles of membrane composition are still debated. Herein, the response of lipopolysaccharide-truncated Escherichia coli K12 mutants to TiO2 nanoparticles (TiO2NPs, exposure in dark) is addressed at the molecular, single cell, and population levels by transcriptomics, fluorescence assays, cell nanomechanics and electrohydrodynamics. We show that outer core-free lipopolysaccharides featuring intact inner core increase cell sensitivity to TiO2NPs. TiO2NPs operate as membrane strippers, which induce osmotic stress, inactivate cell osmoregulation and initiate lipid peroxidation, which ultimately leads to genesis of membrane vesicles. In itself, truncation of lipopolysaccharide inner core triggers membrane permeabilization/depolarization, lipid peroxidation and hypervesiculation. In turn, it favors the regulation of TiO2NP-mediated changes in cell Turgor stress and leads to efficient vesicle-facilitated release of damaged membrane components. Remarkably, vesicles further act as electrostatic baits for TiO2NPs, thereby mitigating TiO2NPs toxicity. Altogether, we highlight antagonistic lipopolysaccharide-dependent bacterial responses to nanoparticles and we show that the destabilized membrane can generate unexpected resistance phenotype.
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Affiliation(s)
| | | | | | | | | | - Eva Delatour
- Université de Lorraine, CNRS, LIEC, Metz, France
| | | | - Marc Offroy
- Université de Lorraine, CNRS, LIEC, Nancy, France
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Lartiges B, El Samrani AG, Montargès-Pelletier E, Bihannic I, Briois V, Michot L. Aggregating ability of ferric chloride in the presence of phosphate ligand. Water Res 2019; 164:114960. [PMID: 31408758 DOI: 10.1016/j.watres.2019.114960] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 08/02/2019] [Accepted: 08/06/2019] [Indexed: 06/10/2023]
Abstract
Complexing anions such as phosphate or silicate play an ambivalent role in the performance of hydrolyzing metal coagulants: On one hand, they significantly interfere with the hydrolytic pathway of conventional iron or aluminum coagulants, the associated destabilization mechanism remaining rather elusive; on the other hand, they have been shown to be key ingredients in the formulation of innovative coagulant solutions exhibiting improved removal efficiency, their action mechanism at the molecular scale being presently poorly understood. In this paper, we explore the effect of small additions of phosphate ligand on the chemical coagulation of silica nanoparticles with ferric chloride. Transmission Electron Microscopy-Energy Dispersed X-ray Spectroscopy (TEM-EDXS) combined with Extended X-ray absorption Fine Structure Spectroscopy (EXAFS) at the Fe K-edge are used to provide an insight into the nature of coagulant species, whereas jar-tests, laser diffraction, Small Angle X-ray Scattering (SAXS), and electrophoretic mobility, are used to investigate the aggregation dynamics of silica particles in the presence of phosphate ligand. We show that, in spite of a slight increase in the consumption of iron coagulant, the addition of phosphate significantly improves the formation of silica aggregates provided that the elemental Fe/P ratio remains above 7. Such effects originate from both a large increase in the overall number of coagulant species, the binding of a phosphate ligand terminating the growth of polymeric chains of edge-sharing Fe octahedra, and a change in the nature of the coagulant species that evolves with the Fe/P ratio, small polycations built-up from Fe-oligomers linked by phosphate tetrahedra being eventually formed. Those non-equilibrium nanosize Fe-P coagulant species assemble the silica nanoparticles to form hetero-aggregates whose structure is consistent with a Diffusion-Limited Cluster Aggregation mechanism.
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Affiliation(s)
- B Lartiges
- University of Toulouse (Paul Sabatier), Geosciences Environment Toulouse (UMR CNRS-UPS 5563 IRD 234), 14 Av. E. Belin, 31400, Toulouse, France.
| | - A G El Samrani
- Lebanese University, Platform for Research and Analysis in Environmental Sciences, Doctoral School of Science and Technology, Faculty of Sciences, P.O Box. 5, Campus Rafic Hariri, Beirut, Lebanon.
| | - E Montargès-Pelletier
- University of Lorraine, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR CNRS 7360, 54501, Vandoeuvre-les-Nancy, France
| | - I Bihannic
- University of Lorraine, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR CNRS 7360, 54501, Vandoeuvre-les-Nancy, France
| | - V Briois
- SOLEIL Synchrotron, UR1-CNRS, l'Orme des Merisiers, BP 48, Saint-Aubin, 91192, Gif-sur-Yvette, France
| | - L Michot
- Laboratoire PHENIX CNRS Sorbonne Université UMR 8234, 4 Place Jussieu, 72522, Paris Cedex 5, France
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Ratié G, Vantelon D, Lotfi Kalahroodi E, Bihannic I, Pierson-Wickmann AC, Davranche M. Iron speciation at the riverbank surface in wetland and potential impact on the mobility of trace metals. Sci Total Environ 2019; 651:443-455. [PMID: 30243164 DOI: 10.1016/j.scitotenv.2018.09.143] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 09/07/2018] [Accepted: 09/10/2018] [Indexed: 06/08/2023]
Abstract
Fe oxyhydroxides in riverbanks and their high binding capacity can be used to hypothesize that riverbanks may act as a "biogeochemical filter" between wetlands and rivers and may constitute a major mechanism in the trapping and flux regulation of chemical elements. Until now, the properties of Fe minerals have been very poorly described in riverbanks. The goals of the present work are to identify Fe speciation in riverbanks where ferric deposits are observed and to determine their impact on the metal behavior (As, Co, Cu, Ni, Pb, Zn, etc.). At the surface, Fe speciation is mainly composed of small poorly crystalline Fe phases, i.e. ferrihydrite (~30%), Fe-OM associations (~40%) as well as crystalline Fe phases, i.e. goethite (~35%). At the subsurface, the Fe distribution is dominated by goethite (~35%) and Fe-mica (~35%), the proportion of which increases at the expense of ferrihydrite and the Fe-OM associations. At the riverbank surface, ferrihydrite and the Fe-OM associations are therefore the main Fe hosting phases in response to (i) the fast Fe(II) oxidation induced by the presence of O2 and (ii) the high amount of OM favoring the formation of nano-phases bound to OM (Fe monomers, polymers and nanoparticles) and preventing mineralogical transformation (ferrihydrite into goethite). During the high-water level period (high flow), a strong erosion of the riverbank transfers these ferric deposits into the river. However, the physicochemical parameters of the river (pH 6.6-7.6 and continuous oxic conditions) do not promote the dissolution of Fe oxyhydroxides and OM. Ferric deposits and the associated trace metals are therefore maintained as colloids/particles and are exported to the outlet. All of the results presented here demonstrate that the ferric deposits trap metals on a seasonal basis and are therefore a key factor in the mobilization of metals during riverbank erosion by river flow.
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Affiliation(s)
- G Ratié
- SOLEIL Synchrotron, L'orme des merisiers, Saint Aubin BP48, 91192 Gif-sur-Yvette Cedex, France.
| | - D Vantelon
- SOLEIL Synchrotron, L'orme des merisiers, Saint Aubin BP48, 91192 Gif-sur-Yvette Cedex, France
| | - E Lotfi Kalahroodi
- Géosciences Rennes, UMR 6118, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - I Bihannic
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France
| | - A C Pierson-Wickmann
- Géosciences Rennes, UMR 6118, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - M Davranche
- Géosciences Rennes, UMR 6118, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
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Ferrage E, Hubert F, Baronnet A, Grauby O, Tertre E, Delville A, Bihannic I, Prêt D, Michot LJ, Levitz P. Influence of crystal structure defects on the small-angle neutron scattering/diffraction patterns of clay-rich porous media. J Appl Crystallogr 2018. [DOI: 10.1107/s160057671801052x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Analysing the structure and microstructure of compacted swelling clay minerals is important because of the applications of these minerals in engineering and environmental sciences. Given the typical sub-micrometre size of the particles and pores in clays, small-angle scattering techniques are well suited for such analysis. Interpretation of the intensity patterns, however, remains complex, especially in the intermediate region between the first Bragg peak and the small-angle range. In this study, theoretical small-angle neutron scattering and neutron diffraction patterns are calculated for three-dimensional virtual porous media representative of packed swelling clay particles (i.e. 0.1–0.2 µm size fraction of vermiculite). This packing represents the distribution of the size, shape and particle orientation of a bulk vermiculite sample, for which experimental scattering/diffraction patterns were also collected. It was found that a good fit between the experimental and calculated scattering/diffraction profiles can be obtained only if the presence of crystal-structure defects in the particles is considered. The existence of such defects was supported by transmission electron microscopy analysis. Their influence on power law exponents extracted from intensity profiles is assessed in detail. The analysis is further extended to the influence of mineral dehydration and particle orientation on the intensity profiles. This work shows that using virtual porous media as toy models makes it possible to evaluate the roles of different microstructural parameters in the extent of variation of power law exponents. Such knowledge can be used for better interpretation of small-angle scattering data of natural compacted swelling clay-rich media.
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Beaussart A, Caillet C, Bihannic I, Zimmermann R, Duval JFL. Remarkable reversal of electrostatic interaction forces on zwitterionic soft nanointerfaces in a monovalent aqueous electrolyte: an AFM study at the single nanoparticle level. Nanoscale 2018; 10:3181-3190. [PMID: 29372221 DOI: 10.1039/c7nr07976a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Soft (nano)colloids are increasingly used in medical applications due to the versatile options they offer in terms of e.g. tunable chemical composition, adaptable physical properties and (bio)functionalization perspectives. Obtaining a clear understanding of the nature of the interaction forces that such particles experience with neighboring charged (bio)surfaces is a mandatory prerequisite to draw a comprehensive and mechanistic picture of their stability and reactivity and to further optimize their current functionalities. In this study, adopting an original strategy for nanoparticle attachment to atomic force microscopy (AFM) tips, we demonstrate that the sign of electrostatic forces between carboxylate-terminated poly(amidoamine) nanodendrimers (∼9 nm in diameter) and planar cysteamine-coated gold surfaces can be tailored under fixed pH conditions upon the sole variation of the monovalent salt concentration in solution. The origin of this unconventional electrostatic force reversal is deciphered upon confrontation between AFM force measurements and mean-field force evaluation performed beyond the Derjaguin approximation by integrating the dendrimer and cysteamine electrostatic properties derived independently from electrokinetic measurements. It is shown that the electrostatic force reversal (i) originates from the zwitterionic character of the nanodendrimer-solution interphase, and (ii) becomes operational under the strict condition that the sub-nanometric separation distance between peripheral carboxylate groups and intraparticulate amines is of the order of the characteristic electric Debye layer thickness. The possibility to mediate - via suitable adjustment of monovalent salt content in solution - both the magnitude and sign of the electrostatic forces acting on soft interfaces with zwitterionic functionality paves the way for the design of innovative strategies to control the stability of nanoparticles against aggregation, and to modulate their adhesion onto inorganic surfaces or living organisms.
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Affiliation(s)
- Audrey Beaussart
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, Vandoeuvre-lès-Nancy F-54501, France
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11
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Kanbar HJ, Montargès-Pelletier E, Losson B, Bihannic I, Gley R, Bauer A, Villieras F, Manceau L, El Samrani AG, Kazpard V, Mansuy-Huault L. Iron mineralogy as a fingerprint of former steelmaking activities in river sediments. Sci Total Environ 2017; 599-600:540-553. [PMID: 28494280 DOI: 10.1016/j.scitotenv.2017.04.156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 04/04/2017] [Accepted: 04/20/2017] [Indexed: 06/07/2023]
Abstract
Submerged sediment cores were collected upstream of a dam in the Orne River, northeastern France. This dam was built in the context of steelmaking to constitute a water reservoir for blast furnace cooling and wet cleaning of furnace smokes. The dam also enhanced sediment deposition in the upstream zone. This study was performed to unravel the contamination status of sediments and to evidence possible contribution sources. The sediment layers were analyzed for water content, grain size, chemical composition, crystalline phases at a bulk scale and poorly crystalline and amorphous phases at a sub-micrometer scale. Visual aspect, texture, color, and chemical and mineralogical analyses showed that the settled sediments were mainly composed of fine black matter, certainly comprising steelmaking by-products. Those materials were highly enriched with Fe, Zn, Pb and other trace metals, except for a relatively thin layer of surficial sediments that had settled more recently. Bulk mineralogy revealed crystalline iron minerals, such as magnetite, goethite, wuestite and pyrite, in the deep layers of the sediment cores. Furthermore, microscopic investigations evidenced the presence of ferrospheres, goethite nanoparticles and newly formed Fe-aluminosilicates; all originating from the former steelmaking facilities. The variation of iron mineralogy, combined with specific chemical profiles and other sediment features, demonstrate the different contributions that constitute the sediment deposit. Furthermore, chemical and mineralogical features of goethite and Fe-aluminosilicates could be used as a fingerprint for such contaminated sediments.
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Affiliation(s)
- Hussein Jaafar Kanbar
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), LTER Zone Atelier Moselle, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, 54500 Vandœuvre-lès-Nancy, France; Research and Analysis Platform for Environmental Sciences (PRASE), Doctoral School of Sciences and Technology (EDST), Faculty of Sciences, Lebanese University, P.O. 5, Rafic Hariri Campus, 1003 Hadat, Lebanon.
| | - Emmanuelle Montargès-Pelletier
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), LTER Zone Atelier Moselle, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, 54500 Vandœuvre-lès-Nancy, France.
| | - Benoit Losson
- Université de Lorraine, LOTERR, UFR SHS-Metz, Ile du Saulcy, CS60228, 57045 Metz cedex 01, France
| | - Isabelle Bihannic
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), LTER Zone Atelier Moselle, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, 54500 Vandœuvre-lès-Nancy, France
| | - Renaud Gley
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), LTER Zone Atelier Moselle, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, 54500 Vandœuvre-lès-Nancy, France
| | - Allan Bauer
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), LTER Zone Atelier Moselle, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, 54500 Vandœuvre-lès-Nancy, France
| | - Frederic Villieras
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), LTER Zone Atelier Moselle, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, 54500 Vandœuvre-lès-Nancy, France
| | - Luc Manceau
- Université de Lorraine, LOTERR, UFR SHS-Metz, Ile du Saulcy, CS60228, 57045 Metz cedex 01, France
| | - Antoine G El Samrani
- Research and Analysis Platform for Environmental Sciences (PRASE), Doctoral School of Sciences and Technology (EDST), Faculty of Sciences, Lebanese University, P.O. 5, Rafic Hariri Campus, 1003 Hadat, Lebanon
| | - Veronique Kazpard
- Research and Analysis Platform for Environmental Sciences (PRASE), Doctoral School of Sciences and Technology (EDST), Faculty of Sciences, Lebanese University, P.O. 5, Rafic Hariri Campus, 1003 Hadat, Lebanon
| | - Laurence Mansuy-Huault
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), LTER Zone Atelier Moselle, 54500 Vandœuvre-lès-Nancy, France; Université de Lorraine, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, 54500 Vandœuvre-lès-Nancy, France
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12
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Frère L, Paul-Pont I, Rinnert E, Petton S, Jaffré J, Bihannic I, Soudant P, Lambert C, Huvet A. Influence of environmental and anthropogenic factors on the composition, concentration and spatial distribution of microplastics: A case study of the Bay of Brest (Brittany, France). Environ Pollut 2017; 225:211-222. [PMID: 28371735 DOI: 10.1016/j.envpol.2017.03.023] [Citation(s) in RCA: 202] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 05/23/2023]
Abstract
The concentration and spatial distribution of microplastics in the Bay of Brest (Brittany, France) was investigated in two surveys. Surface water and sediment were sampled at nine locations in areas characterized by contrasting anthropic pressures, riverine influences or water mixing. Microplastics were categorized by their polymer type and size class. Microplastic contamination in surface water and sediment was dominated by polyethylene fragments (PE, 53-67%) followed by polypropylene (PP, 16-30%) and polystyrene (PS, 16-17%) microparticles. The presence of buoyant microplastics (PE, PP and PS) in sediment suggests the existence of physical and/or biological processes leading to vertical transfer of lightweight microplastics in the bay. In sediment (upper 5 cm), the percentage of particles identified by Raman micro-spectroscopy was lower (41%) than in surface water (79%) and may explain the apparent low concentration observed in this matrix (0.97 ± 2.08 MP kg-1 dry sediment). Mean microplastic concentration was 0.24 ± 0.35 MP m-3 in surface water. We suggest that the observed spatial MP distribution is related to proximity to urbanized areas and to hydrodynamics in the bay. A particle dispersal model was used to study the influence of hydrodynamics on surface microplastic distribution. The outputs of the model showed the presence of a transitional convergence zone in the centre of the bay during flood tide, where floating debris coming from the northern and southern parts of the bay tends to accumulate before being expelled from the bay. Further modelling work and observations integrating (i) the complex vertical motion of microplastics, and (ii) their point sources is required to better understand the fate of microplastics in such a complex coastal ecosystem.
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Affiliation(s)
- L Frère
- LEMAR UMR 6539 CNRS/UBO/IRD/Ifremer, IUEM, rue Dumont d'Urville, 29280 Plouzané, France
| | - I Paul-Pont
- LEMAR UMR 6539 CNRS/UBO/IRD/Ifremer, IUEM, rue Dumont d'Urville, 29280 Plouzané, France.
| | - E Rinnert
- Ifremer, Laboratoire Détection, Capteurs et Mesures, Centre de Bretagne, ZI de la Pointe du Diable, CS 10070, 29280 Plouzané, France
| | - S Petton
- Ifremer, LEMAR UMR 6539 CNRS/UBO/IRD/Ifremer, Centre de Bretagne, ZI de la Pointe du Diable, CS 10070, 29280 Plouzané, France
| | - J Jaffré
- LEMAR UMR 6539 CNRS/UBO/IRD/Ifremer, IUEM, rue Dumont d'Urville, 29280 Plouzané, France
| | - I Bihannic
- LEMAR UMR 6539 CNRS/UBO/IRD/Ifremer, IUEM, rue Dumont d'Urville, 29280 Plouzané, France
| | - P Soudant
- LEMAR UMR 6539 CNRS/UBO/IRD/Ifremer, IUEM, rue Dumont d'Urville, 29280 Plouzané, France
| | - C Lambert
- LEMAR UMR 6539 CNRS/UBO/IRD/Ifremer, IUEM, rue Dumont d'Urville, 29280 Plouzané, France
| | - A Huvet
- Ifremer, LEMAR UMR 6539 CNRS/UBO/IRD/Ifremer, Centre de Bretagne, ZI de la Pointe du Diable, CS 10070, 29280 Plouzané, France
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13
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Rotureau E, Waldvogel Y, Pinheiro JP, Farinha JPS, Bihannic I, Présent RM, Duval JFL. Structural effects of soft nanoparticulate ligands on trace metal complexation thermodynamics. Phys Chem Chem Phys 2016; 18:31711-31724. [PMID: 27841406 DOI: 10.1039/c6cp06880d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Metal binding to natural soft colloids is difficult to address due to the inherent heterogeneity of their reactive polyelectrolytic volume and the modifications of their shell structure following changes in e.g. solution pH, salinity or temperature. In this work, we investigate the impacts of temperature- and salinity-mediated modifications of the shell structure of polymeric ligand nanoparticles on the thermodynamics of divalent metal ions Cd(ii)-complexation. The adopted particles consist of a glassy core decorated by a fine-tunable poly(N-isopropylacrylamide) anionic corona. According to synthesis, the charges originating from the metal binding carboxylic moieties supported by the corona chains are located preferentially either in the vicinity of the core or at the outer shell periphery (p(MA-N) and p(N-AA) particles, respectively). Stability constants (KML) of cadmium-nanoparticle complexes are measured under different temperature and salinity conditions using electroanalytical techniques. The obtained KML is clearly impacted by the location of the carboxylic functional groups within the shell as p(MA-N) leads to stronger nanoparticulate Cd complexes than p(N-AA). The dependence of KML on solution salinity for p(N-AA) is shown to be consistent with a binding of Cd to peripheral carboxylic groups driven by Coulombic interactions (Eigen-Fuoss mechanism for ions-pairing) or with particle electrostatic features operating at the edge of the shell Donnan volume. For p(MA-N) particulate ligands, a scenario where metal binding occurs within the intraparticulate Donnan phase correctly reproduces the experimental findings. Careful analysis of electroanalytical data further evidences that complexation of metal ions by core-shell particles significantly differ according to the location and distribution of the metal-binding sites throughout the reactive shell. This complexation heterogeneity is basically enhanced with increasing temperature i.e. upon significant increase of particle shell shrinking, which suggests that the contraction of the reactive phase volume of the particulate ligands promotes cooperative metal binding effects.
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Affiliation(s)
- Elise Rotureau
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, Vandoeuvre-lès-Nancy F-54501, France and Université de Lorraine, LIEC, UMR 7360, Vandoeuvre-lès-Nancy F-54501, France.
| | - Yves Waldvogel
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, Vandoeuvre-lès-Nancy F-54501, France and Université de Lorraine, LIEC, UMR 7360, Vandoeuvre-lès-Nancy F-54501, France.
| | - José P Pinheiro
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, Vandoeuvre-lès-Nancy F-54501, France and Université de Lorraine, LIEC, UMR 7360, Vandoeuvre-lès-Nancy F-54501, France.
| | - José Paulo S Farinha
- Centro de Quimica Fisica Molecular and IN-Institute of Nanoscience and Nanotechnology, Instituto Superior Tecnico, University of Lisbon, 1049-001 Lisboa, Portugal
| | - Isabelle Bihannic
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, Vandoeuvre-lès-Nancy F-54501, France and Université de Lorraine, LIEC, UMR 7360, Vandoeuvre-lès-Nancy F-54501, France.
| | - Romain M Présent
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, Vandoeuvre-lès-Nancy F-54501, France and Université de Lorraine, LIEC, UMR 7360, Vandoeuvre-lès-Nancy F-54501, France.
| | - Jérôme F L Duval
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR 7360, Vandoeuvre-lès-Nancy F-54501, France and Université de Lorraine, LIEC, UMR 7360, Vandoeuvre-lès-Nancy F-54501, France.
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14
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Martin JRS, Bihannic I, Santos C, Farinha JPS, Demé B, Leermakers FAM, Pinheiro JP, Rotureau E, Duval JFL. Structure of Multiresponsive Brush-Decorated Nanoparticles: A Combined Electrokinetic, DLS, and SANS Study. Langmuir 2015; 31:4779-4790. [PMID: 25840116 DOI: 10.1021/acs.langmuir.5b00530] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Particles consisting of a glassy poly(methyl methacrylate) core (ca. 40 nm in radius) decorated with a poly(N-isopropylacrylamide) anionic corona are synthesized using either methacrylic acid (MA) or acrylic acid (AA) as reactive comonomers in the shell. The different reactivity ratios of MA and AA toward N-isopropylacrylamide originates p(MA-N) and p(N-AA) particles with carboxylate charges supposedly located, preferentially, in the close vicinity of the core and at the shell periphery, respectively. The corresponding swelling features of these nanoparticles are addressed over a broad range of pH values (4 to 7.5), NaNO3 concentrations (3 to 200 mM), and temperatures (15 to 45 °C) by dynamic light scattering (DLS) and small angle neutron scattering (SANS). DLS shows that the swelling of the particle shells increases their thickness from ∼10 to 90 nm with decreasing temperature, ionic strength, or increasing pH, with the effect being more pronounced for p(N-AA) whose lower critical solution temperature is shifted to higher values compared to that of p(MA-N). Potentiometric titration and electrokinetic results further reflect the easier dissociation of carboxyl groups in p(N-AA) and a marked heterogeneous interfacial swelling of the latter with decreasing solution salt content. The DLS response of both particles is attributed to the multiresponsive nature of a peripheral dilute shell, while SANS only probes the presence of a quasi-solvent-free dense polymer layer, condensed on the core surface. The thickness of that layer slightly increases from ∼6 to 9.5 nm with increasing temperature from 15 to 45 °C (at 15 mM NaNO3 and pH 5) due to the collapse of the outer dilute shell layer. Overall, results evidence a nonideal brush behavior of p(MA-N) and p(N-AA) and their microphase segregated shell structure, which supports some of the conclusions recently formulated from approximate self-consistent mean-field computations.
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Affiliation(s)
- Jennifer R S Martin
- †CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, Vandoeuvre-lès-Nancy F-54501, France
- ‡Université de Lorraine, LIEC, UMR7360, Vandoeuvre-lès-Nancy F-54501, France
| | - Isabelle Bihannic
- †CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, Vandoeuvre-lès-Nancy F-54501, France
- ‡Université de Lorraine, LIEC, UMR7360, Vandoeuvre-lès-Nancy F-54501, France
| | - Catarina Santos
- §Centro de Quimica Fisica Molecular and IN-Institute of Nanoscience and Nanotechnology, Instituto Superior Tecnico, University of Lisbon, 1049-001 Lisboa, Portugal
| | - José Paulo S Farinha
- §Centro de Quimica Fisica Molecular and IN-Institute of Nanoscience and Nanotechnology, Instituto Superior Tecnico, University of Lisbon, 1049-001 Lisboa, Portugal
| | - Bruno Demé
- ∥Institut Laue-Langevin (ILL), BP 156-X, F-38042 Grenoble Cedex, France
| | - Frans A M Leermakers
- ⊥Laboratory of Physical Chemistry and Colloid Science, Wageningen University and Research Center, Dreijenplein 8, 6703 HB Wageningen, The Netherlands
| | - José P Pinheiro
- †CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, Vandoeuvre-lès-Nancy F-54501, France
- ‡Université de Lorraine, LIEC, UMR7360, Vandoeuvre-lès-Nancy F-54501, France
| | - Elise Rotureau
- †CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, Vandoeuvre-lès-Nancy F-54501, France
- ‡Université de Lorraine, LIEC, UMR7360, Vandoeuvre-lès-Nancy F-54501, France
| | - Jérôme F L Duval
- †CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, Vandoeuvre-lès-Nancy F-54501, France
- ‡Université de Lorraine, LIEC, UMR7360, Vandoeuvre-lès-Nancy F-54501, France
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Jégou C, Kervarec N, Cérantola S, Bihannic I, Stiger-Pouvreau V. NMR use to quantify phlorotannins: the case of Cystoseira tamariscifolia, a phloroglucinol-producing brown macroalga in Brittany (France). Talanta 2015; 135:1-6. [PMID: 25640118 DOI: 10.1016/j.talanta.2014.11.059] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 11/19/2014] [Accepted: 11/22/2014] [Indexed: 11/16/2022]
Abstract
Among the most renowned natural products from brown algae, phlorotannins are phloroglucinol polymers that have been extensively studied, both for their biotechnological potential and their interest in chemical ecology. The accurate quantification of these compounds is a key point to understand their role as mediators of chemical defense. In recent years, the Folin-Ciocalteu assay has remained a classic protocol for phlorotannin quantification, even though it frequently leads to over-estimations. Furthermore, the quantification of the whole pool of phlorotannins may not be relevant in ecological surveys. In this study, we propose a rapid (1)H qNMR method for the quantification of phlorotannins. We identified phloroglucinol as the main phenolic compound produced by the brown macroalga Cystoseira tamariscifolia. This monomer was detected in vivo using (1)H HR-MAS spectroscopy. We quantified this molecule through (1)H qNMR experiments using TSP as internal standard. The results are discussed by comparison with a standard Folin-Ciocalteu assay performed on purified extracts. The accuracy and simplicity of qNMR makes this method a good candidate as a standard phlorotannin assay.
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Affiliation(s)
- Camille Jégou
- Laboratoire Universitaire de Biodiversité et d׳Écologie Microbienne (EA 3882), IUT de Quimper, Université de Bretagne Occidentale, 6 rue de l׳Université, 29000 Quimper, France
| | - Nelly Kervarec
- Service commun de Résonance Magnétique Nucléaire, UFR Sciences, Université de Bretagne Occidentale, 6 avenue Victor Le Gorgeu-CS93837, 29238 Brest Cedex 3, France
| | - Stéphane Cérantola
- Service commun de Résonance Magnétique Nucléaire, UFR Sciences, Université de Bretagne Occidentale, 6 avenue Victor Le Gorgeu-CS93837, 29238 Brest Cedex 3, France
| | - Isabelle Bihannic
- Laboratoire des Sciences de l׳Environnement Marin (UMR 6539), Institut Universitaire Européen de la Mer, Université de Bretagne Occidentale, rue Dumont d׳Urville, 29280 Plouzané, France
| | - Valérie Stiger-Pouvreau
- Laboratoire des Sciences de l׳Environnement Marin (UMR 6539), Institut Universitaire Européen de la Mer, Université de Bretagne Occidentale, rue Dumont d׳Urville, 29280 Plouzané, France.
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16
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Zimmermann R, Romeis D, Bihannic I, Cohen Stuart M, Sommer JU, Werner C, Duval JFL. Electrokinetics as an alternative to neutron reflectivity for evaluation of segment density distribution in PEO brushes. Soft Matter 2014; 10:7804-7809. [PMID: 25144904 DOI: 10.1039/c4sm01315h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Unravelling details of charge, structure and molecular interactions of functional polymer coatings defines an important analytical challenge that requires the extension of current methodologies. In this article we demonstrate how streaming current measurements interpreted with combined self consistent field (SCF) and soft surface electrokinetic theories allow the evaluation of the segment distribution within poly(ethylene oxide) (PEO) brushes beyond the resolution limits of neutron reflectivity technique.
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Affiliation(s)
- Ralf Zimmermann
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials Dresden, Hohe Strasse 6, 01069 Dresden, Germany.
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17
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Landman J, Paineau E, Davidson P, Bihannic I, Michot LJ, Philippe AM, Petukhov AV, Lekkerkerker HNW. Effects of Added Silica Nanoparticles on the Nematic Liquid Crystal Phase Formation in Beidellite Suspensions. J Phys Chem B 2014; 118:4913-9. [DOI: 10.1021/jp500036v] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jasper Landman
- Van’t Hoff Laboratory for Physical
and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University, Padualaan 8, 3584
CH Utrecht, The Netherlands
| | - Erwan Paineau
- Laboratoire de Physique des Solides, UMR 8502 CNRS, Université Paris-Sud, Bâtiment 510, 91405 Orsay Cedex, France
| | - Patrick Davidson
- Laboratoire de Physique des Solides, UMR 8502 CNRS, Université Paris-Sud, Bâtiment 510, 91405 Orsay Cedex, France
| | - Isabelle Bihannic
- Laboratoire
Interdisciplinaire des Environnements Continentaux, UMR 7360 CNRS, Université de Lorraine, 15 avenue du Charmois, 54500 Vandoeuvre, France
| | - Laurent J. Michot
- Laboratoire
Interdisciplinaire des Environnements Continentaux, UMR 7360 CNRS, Université de Lorraine, 15 avenue du Charmois, 54500 Vandoeuvre, France
| | - Adrian-Marie Philippe
- Laboratoire d’Energétique et de Mécanique Théorique
et Appliquée, UMR 7563 CNRS, Université de Lorraine, 2 avenue
de la Forêt de Haye, TSA 60604, 54518 Vandoeuvre, France
| | - Andrei V. Petukhov
- Van’t Hoff Laboratory for Physical
and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University, Padualaan 8, 3584
CH Utrecht, The Netherlands
| | - Henk N. W. Lekkerkerker
- Van’t Hoff Laboratory for Physical
and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University, Padualaan 8, 3584
CH Utrecht, The Netherlands
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18
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Philippe AM, Baravian C, Bezuglyy V, Angilella JR, Meneau F, Bihannic I, Michot LJ. Rheological study of two-dimensional very anisometric colloidal particle suspensions: from shear-induced orientation to viscous dissipation. Langmuir 2013; 29:5315-5324. [PMID: 23544905 DOI: 10.1021/la400111w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In the present study, we investigate the evolution with shear of the viscosity of aqueous suspensions of size-selected natural swelling clay minerals for volume fractions extending from isotropic liquids to weak nematic gels. Such suspensions are strongly shear-thinning, a feature that is systematically observed for suspensions of nonspherical particles and that is linked to their orientational properties. We then combined our rheological measurements with small-angle X-ray scattering experiments that, after appropriate treatment, provide the orientational field of the particles. Whatever the clay nature, particle size, and volume fraction, this orientational field was shown to depend only on a nondimensional Péclet number (Pe) defined for one isolated particle as the ratio between hydrodynamic energy and Brownian thermal energy. The measured orientational fields were then directly compared to those obtained for infinitely thin disks through a numerical computation of the Fokker-Plank equation. Even in cases where multiple hydrodynamic interactions dominate, qualitative agreement between both orientational fields is observed, especially at high Péclet number. We have then used an effective approach to assess the viscosity of these suspensions through the definition of an effective volume fraction. Using such an approach, we have been able to transform the relationship between viscosity and volume fraction (ηr = f(φ)) into a relationship that links viscosity with both flow and volume fraction (ηr = f(φ, Pe)).
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Affiliation(s)
- A M Philippe
- Laboratoire d'Énergétique et de Mécanique Théorique et Appliquée, Université de Lorraine - CNRS, UMR 7563, 2 Avenue de la Forêt de Haye, TSA 60604 54518 Vandoeuvre Cedex, France.
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Michot LJ, Bihannic I, Thomas F, Lartiges BS, Waldvogel Y, Caillet C, Thieme J, Funari SS, Levitz P. Coagulation of Na-montmorillonite by inorganic cations at neutral pH. A combined transmission X-ray microscopy, small angle and wide angle X-ray scattering study. Langmuir 2013; 29:3500-3510. [PMID: 23421550 DOI: 10.1021/la400245n] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The coagulation of sodium montmorillonite by inorganic salts (NaNO3, Ca(NO3)2 and La(NO3)3) was studied by combining classical turbidity measurements with wide-angle-X-ray scattering (WAXS), small-angle-X-ray scattering (SAXS), and transmission X-ray microscopy (TXM). Using size-selected samples, such a combination, associated with an original quantitative treatment of TXM images, provides a true multiscale investigation of the formed structures in a spatial range extending from a few ångstroms to a few micrometers. We then show that, at neutral pH and starting with fully Na-exchanged samples, coagulation proceeds via the formation of stacks of particles with a slight mismatch between layers. These stacks arrange themselves into larger porous anisotropic particles, the porosity of which depends on the valence of the cation used for coagulation experiments. Face-face coagulation is clearly dominant under those conditions, and no evidence for significant face-edge coagulation was found. These structures appear to arrange as larger clusters, the organization of which should control the mechanical properties of the flocs.
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Affiliation(s)
- Laurent J Michot
- Laboratoire Interdisciplinaire des Environnements Continentaux, UMR 7360 CNRS-Université de Lorraine, Vandœuvre, France.
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Paineau E, Dozov I, Philippe AM, Bihannic I, Meneau F, Baravian C, Michot LJ, Davidson P. In-situ SAXS study of aqueous clay suspensions submitted to alternating current electric fields. J Phys Chem B 2012; 116:13516-24. [PMID: 23106195 DOI: 10.1021/jp3064728] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Aqueous colloidal suspensions of clay platelets display a sol/gel transition that is not yet understood. Depending on the nature of the clay, liquid-crystalline behavior may also be observed. For example, the suspensions of beidellite display a nematic phase whereas those of montmorillonite do not. Both beidellite and montmorillonite have a "TOT" structure but the structural electric charge is located in the tetrahedral layer for the former and in the octahedral layer for the latter. We built a setup to perform SAXS experiments on complex fluids submitted to an electric field in situ. We found that the fluid nematic phase of beidellite suspensions readily aligns in the field. However, the field had no influence on the gels, showing that the orientational degrees of freedom of the platelets are effectively frozen. Moreover, strong platelet alignment was induced by the field in the isotropic phase of both clays, in a similar way, regardless of their ability to form a nematic phase. This surprising result would suggest that the orientational degrees of freedom are not directly involved in the sol/gel transition. The ability to induce orientational order in the isotropic phase of clay suspensions can be exploited to prepare materials of controlled anisotropy.
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Affiliation(s)
- Erwan Paineau
- Laboratoire de Physique des Solides, UMR 8502, Université Paris-Sud, Bâtiment 510, 91405 Orsay Cedex, France.
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Paineau E, Dozov I, Bihannic I, Baravian C, Krapf MEM, Philippe AM, Rouzière S, Michot LJ, Davidson P. Tailoring highly oriented and micropatterned clay/polymer nanocomposites by applying an a.c. electric field. ACS Appl Mater Interfaces 2012; 4:4296-4301. [PMID: 22833688 DOI: 10.1021/am300980r] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Clay/polymer nanocomposites have recently raised much interest because of their widespread industrial applications. Nevertheless, controlling both clay platelet exfoliation and orientation during polymerization still remains challenging. Herein, we report the elaboration of clay/polymer nanocomposite hydrogels from aqueous suspensions of natural swelling clays submitted to high-frequency a.c. electric fields. X-ray scattering experiments have confirmed the complete exfoliation of the clay sheets in the polymer matrix, even after polymerization. Moreover, polarized light microscopy shows that the clay platelets were perfectly oriented by the electric field and that this field-induced alignment was frozen in by in situ photopolymerization. This procedure allowed us to not only produce uniformly aligned samples but also pattern platelet orientation, at length scales down to 20 μm. This straightforward and cheap nanocomposite patterning technique can be easily extended to a wide range of natural or synthetic inorganic anisotropic particles.
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Affiliation(s)
- Erwan Paineau
- Laboratoire de Physique des Solides, UMR 8502, Paris-Sud University, Bâtiment 510, 91405 Orsay Cedex, France.
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Tertre E, Ferrage E, Bihannic I, Michot L, Prêt D. Influence of the ionic strength and solid/solution ratio on Ca(II)-for-Na+ exchange on montmorillonite. Part 2: Understanding the effect of the m/V ratio. Implications for pore water composition and element transport in natural media. J Colloid Interface Sci 2011; 363:334-47. [DOI: 10.1016/j.jcis.2011.07.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 06/29/2011] [Accepted: 07/01/2011] [Indexed: 10/17/2022]
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Paineau E, Michot LJ, Bihannic I, Baravian C. Aqueous suspensions of natural swelling clay minerals. 2. Rheological characterization. Langmuir 2011; 27:7806-7819. [PMID: 21591697 DOI: 10.1021/la2001267] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report in this article a comprehensive investigation of the viscoelastic behavior of different natural colloidal clay minerals in aqueous solution. Rheological experiments were carried out under both dynamic and steady-state conditions, allowing us to derive the elasticity and yield stress. Both parameters can be renormalized for all sizes, ionic strength, and type of clay using in a first approach only the volume of the particles. However, applying such a treatment to various clays of similar shapes and sizes yields differences that can be linked to the repulsion strength and charge location in the swelling clays. The stronger the repulsive interactions, the better the orientation of clay particles in flows. In addition, a master linear relationship between the elasticity and yield stress whose value corresponds to a critical deformation of 0.1 was evidenced. Such a relationship may be general for any colloidal suspension of anisometric particles as revealed by the analysis of various experimental data obtained on either disk-shaped or lath- and rod-shaped particles. The particle size dependence of the sol-gel transition was also investigated in detail. To understand why suspensions of larger particles gel at a higher volume fraction, we propose a very simplified view based on the statistical hydrodynamic trapping of a particle by an another one in its neighborhood upon translation and during a short period of time. We show that the key parameter describing this hydrodynamic trapping varies as the cube of the average diameter and captures most features of the sol-gel transition. Finally, we pointed out that in the high shear limit the suspension viscosity is still closely related to electrostatic interactions and follows the same trends as the viscoelastic properties.
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Affiliation(s)
- Erwan Paineau
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL, UMR 7569, BP40 54501 Vandœuvre, Cedex France.
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Dozov I, Paineau E, Davidson P, Antonova K, Baravian C, Bihannic I, Michot LJ. Electric-Field-Induced Perfect Anti-Nematic Order in Isotropic Aqueous Suspensions of a Natural Beidellite Clay. J Phys Chem B 2011; 115:7751-65. [DOI: 10.1021/jp201201x] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- I. Dozov
- Laboratoire de Physique des Solides, UMR 8502 CNRS−Université Paris-Sud, Bât. 510, 91405 Orsay Cedex, France
| | - E. Paineau
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40, 54501 Vandœuvre Cedex, France
| | - P. Davidson
- Laboratoire de Physique des Solides, UMR 8502 CNRS−Université Paris-Sud, Bât. 510, 91405 Orsay Cedex, France
| | - K. Antonova
- Institute of Solid State Physics, Bulgarian Academy of Sciences, Tzarigradsko Chaussee 72, 1784 Sofia, Bulgaria
| | - C. Baravian
- Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France
| | - I. Bihannic
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40, 54501 Vandœuvre Cedex, France
| | - L. J. Michot
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40, 54501 Vandœuvre Cedex, France
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Philippe AM, Baravian C, Imperor-Clerc M, De Silva J, Paineau E, Bihannic I, Davidson P, Meneau F, Levitz P, Michot LJ. Rheo-SAXS investigation of shear-thinning behaviour of very anisometric repulsive disc-like clay suspensions. J Phys Condens Matter 2011; 23:194112. [PMID: 21525562 DOI: 10.1088/0953-8984/23/19/194112] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Aqueous suspensions of swelling clay minerals exhibit a rich and complex rheological behaviour. In particular, these repulsive systems display strong shear-thinning at very low volume fractions in both the isotropic and gel states. In this paper, we investigate the evolution with shear of the orientational distribution of aqueous clay suspensions by synchrotron-based rheo-SAXS experiments using a Couette device. Measurements in radial and tangential configurations were carried out for two swelling clay minerals of similar morphology and size, Wyoming montmorillonite and Idaho beidellite. The shear evolution of the small angle x-ray scattering (SAXS) patterns displays significantly different features for these two minerals. The detailed analysis of the angular dependence of the SAXS patterns in both directions provides the average Euler angles of the statistical effective particle in the shear plane. We show that for both samples, the average orientation is fully controlled by the local shear stress around the particle. We then apply an effective approach to take into account multiple hydrodynamic interactions in the system. Using such an approach, it is possible to calculate the evolution of viscosity as a function of shear rate from the knowledge of the average orientation of the particles. The viscosity thus recalculated almost perfectly matches the measured values as long as collective effects are not too important in the system.
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Affiliation(s)
- A M Philippe
- Laboratoire d'Energétique et de Mécanique Théorique et Appliquée, Nancy University-CNRS, UMR 7563, Vandœuvre Lès Nancy, France.
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Paineau E, Bihannic I, Baravian C, Philippe AM, Davidson P, Levitz P, Funari SS, Rochas C, Michot LJ. Aqueous suspensions of natural swelling clay minerals. 1. Structure and electrostatic interactions. Langmuir 2011; 27:5562-5573. [PMID: 21476528 DOI: 10.1021/la2001255] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this article, we present a general overview of the organization of colloidal charged clay particles in aqueous suspension by studying different natural samples with different structural charges and charge locations. Small-angle X-ray scattering experiments (SAXS) are first used to derive swelling laws that demonstrate the almost perfect exfoliation of clay sheets in suspension. Using a simple approach based on geometrical constraints, we show that these swelling laws can be fully modeled on the basis of morphological parameters only. The validity of this approach was further extended to other clay data from the literature, in particular, synthetic Laponite. For all of the investigated samples, experimental osmotic pressures can be properly described by a Poisson-Boltzmann approach for ionic strength up to 10(-3) M, which reveals that these systems are dominated by repulsive electrostatic interactions. However, a detailed analysis of the Poisson-Boltzmann treatment shows differences in the repulsive potential strength that are not directly linked to the structural charge of the minerals but rather to the charge location in the structure for tetrahedrally charged clays (beidellite and nontronites) undergoing stronger electrostatic repulsions than octahedrally charged samples (montmorillonites, laponite). Only minerals subjected to the strongest electrostatic repulsions present a true isotropic to nematic phase transition in their phase diagrams. The influence of ionic repulsions on the local order of clay platelets was then analyzed through a detailed investigation of the structure factors of the various clay samples. It appears that stronger electrostatic repulsions improve the liquidlike positional local order.
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Affiliation(s)
- Erwan Paineau
- Laboratoire Environnement et Minéralurgie, Nancy Université-CNRS, UMR 7569, BP40 54501 Vandœuvre Cedex, France.
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Bihannic I, Baravian C, Duval JFL, Paineau E, Meneau F, Levitz P, de Silva JP, Davidson P, Michot LJ. Orientational Order of Colloidal Disk-Shaped Particles under Shear-Flow Conditions: a Rheological−Small-Angle X-ray Scattering Study. J Phys Chem B 2010; 114:16347-55. [DOI: 10.1021/jp105714v] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Paineau E, Antonova K, Baravian C, Bihannic I, Davidson P, Dozov I, Impéror-Clerc M, Levitz P, Madsen A, Meneau F, Michot LJ. Liquid-Crystalline Nematic Phase in Aqueous Suspensions of a Disk-Shaped Natural Beidellite Clay. J Phys Chem B 2009; 113:15858-69. [DOI: 10.1021/jp908326y] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- E. Paineau
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - K. Antonova
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - C. Baravian
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - I. Bihannic
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - P. Davidson
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - I. Dozov
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - M. Impéror-Clerc
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - P. Levitz
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - A. Madsen
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - F. Meneau
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
| | - L. J. Michot
- Laboratoire Environnement et Minéralurgie, Nancy University CNRS-INPL UMR 7569, BP40 54501 Vandœuvre Cedex France, Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chaussee 72, Sofia, 1784, Bulgaria, Laboratoire d’Energétique et de Mécanique Théorique et Appliquée, Nancy University UMR 7563 CNRS-INPL-UHP, 2, Avenue de la Forêt de Haye, BP160 54504 Vandœuvre Cedex, France, Laboratoire de Physique des Solides, UMR 8502 CNRS-Université Paris-Sud Bât 510 91405 Orsay
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Blachier C, Michot L, Bihannic I, Barrès O, Jacquet A, Mosquet M. Adsorption of polyamine on clay minerals. J Colloid Interface Sci 2009; 336:599-606. [DOI: 10.1016/j.jcis.2009.04.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Revised: 03/26/2009] [Accepted: 04/03/2009] [Indexed: 11/28/2022]
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Michot LJ, Baravian C, Bihannic I, Maddi S, Moyne C, Duval JFL, Levitz P, Davidson P. Sol-gel and isotropic/nematic transitions in aqueous suspensions of natural nontronite clay. Influence of particle anisotropy. 2. Gel structure and mechanical properties. Langmuir 2009; 25:127-139. [PMID: 19067578 DOI: 10.1021/la801894a] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
After size-selection, the phase behavior of aqueous suspensions of nontronite clay was analyzed by osmotic pressure measurements, rheological experiments, and small-angle X-ray scattering. All the measurements confirm that for ionic strength < or =10(-3) M/L, the system is purely repulsive. By combining results from osmotic pressure measurements and X-ray scattering, it appears that the pressure of the system can be well-described using a simple Poisson-Boltzmann treatment based on the interaction between charged infinite parallel planes. In terms of rheological properties, even if the status of the sol/gel transition remains partially unclear as the number density of particles at the sol-gel transition exhibits a -2 power dependence with average particle size, the yield stress and elasticity of the gels can be easily renormalized for all particle sizes on the basis of the volume of the particles. Furthermore, rheological modeling of the flow curves shows that for all the particles, an approach based on excluded volume effects captures most features of nontronite suspensions. Still, the high shear flow properties of the suspensions that reveal a strong orientation of particles in the flow are affected by electrostatic interactions. This study then shows that the rich phase behavior of clay minerals, notably the fact that some clay minerals display an isotropic/nematic transition while others exhibit a sol-gel transition, requires a full understanding of all the interactions in the system that can only be achieved by working on well-characterized size-selected samples.
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Affiliation(s)
- Laurent J Michot
- Laboratoire Environnement et Mineralurgie, Nancy University, CNRS-INPL UMR 7569 BP40 54501 Vandaeuvre Cedex, France.
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Michot LJ, Bihannic I, Maddi S, Baravian C, Levitz P, Davidson P. Sol/gel and isotropic/nematic transitions in aqueous suspensions of natural nontronite clay. Influence of particle anisotropy. 1. Features of the i/n transition. Langmuir 2008; 24:3127-3139. [PMID: 18303925 DOI: 10.1021/la703506z] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The phase behavior of a natural nontronite clay was studied for size-selected particles by combining osmotic pressure measurements, visual observations under polarized light, and rheological experiments. In parallel, the positional and orientational correlations of the particles were analyzed by small-angle X-ray scattering. Aqueous suspensions of nontronite exhibit a true isotropic/nematic (I/N) transition that occurs before the sol/gel transition, for ionic strengths below 10(-3) M/L. In this region of the phase diagrams, the system appears to be purely repulsive. The I/N transition shifts toward lower volume fractions for increasing particle anisotropy, and its position in the phase diagram agrees well with the theoretical predictions for platelets. SAXS measurements reveal the presence of characteristic interparticular distances in the isotropic, nematic, and gel phases. The swelling law (separation distance vs swelling law) exhibits two regimes. For high volume fractions, the swelling law is one-dimensional as in layered systems and reveals the presence of isolated platelets. At lower volume fraction, distances scale as phi(-1/3), indicating isotropic volumic swelling. Finally, the experimental osmotic pressure curves can be satisfactorily reproduced by considering the interparticle distances between two charged planes whose effective charge is around 10% of the structural charge.
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Affiliation(s)
- Laurent J Michot
- Laboratoire Environnement et Minéralurgie, Nancy University, CNRS-INPL UMR 7569, BP40 54501, Vandoeuvre Cedex, France.
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Michot LJ, Bihannic I, Maddi S, Funari SS, Baravian C, Levitz P, Davidson P. Liquid-crystalline aqueous clay suspensions. Proc Natl Acad Sci U S A 2006; 103:16101-4. [PMID: 17060625 PMCID: PMC1637543 DOI: 10.1073/pnas.0605201103] [Citation(s) in RCA: 155] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2006] [Indexed: 11/18/2022] Open
Abstract
This article demonstrates the occurrence of a true isotropic/nematic transition in colloidal Brownian aqueous suspensions of natural nontronite clay. The liquid-crystalline character is further evidenced by polarized light microscopy and small-angle x-ray scattering experiments in the presence and absence of modest external magnetic fields. The complete phase diagram ionic strength/volume fraction then exhibits a clear biphasic domain in the sol region just before the gel transition in contrast with the situation observed for other swelling clays in which the sol/gel transition hinders the isotropic/nematic transition. Small-angle x-ray scattering measurements of gel samples reveal strong positional and orientational orders of the particles, proving unambiguously the nematic character of the gel and, thus, clearly refuting the still prevalent "house of cards" model, which explains the gel structure by means of attractive interactions between clay platelets. Such order also is observed in various other swelling clay minerals; therefore, this very general behavior must be taken into account to reach a better understanding of the rheological properties and phase behavior of these systems.
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Affiliation(s)
- Laurent J. Michot
- *Laboratoire Environnement et Minéralurgie, Nancy Université Unité Mixte de Recherche 7569, Centre National de la Recherche Scientifique–Institut National Polytechnique de Lorraine, BP40, 54501 Vandœuvre Cedex, France
| | - Isabelle Bihannic
- *Laboratoire Environnement et Minéralurgie, Nancy Université Unité Mixte de Recherche 7569, Centre National de la Recherche Scientifique–Institut National Polytechnique de Lorraine, BP40, 54501 Vandœuvre Cedex, France
| | - Solange Maddi
- *Laboratoire Environnement et Minéralurgie, Nancy Université Unité Mixte de Recherche 7569, Centre National de la Recherche Scientifique–Institut National Polytechnique de Lorraine, BP40, 54501 Vandœuvre Cedex, France
| | | | - Christophe Baravian
- Laboratoire d'Energétique et de Mécanique Théorique et Appliqué, Nancy Université Unité Mixte de Recherche 7563, Centre National de la Recherche Scientifique–Institut National Polytechnique de Lorraine–Université Henri Poincaré, 2 Avenue de la Forêt de Haye, BP160, 54504 Vandœuvre Cedex, France
| | - Pierre Levitz
- Laboratoire de Physique de la Matière Condensée, Unité Mixte de Recherche 7643, Centre National de la Recherche Scientifique–École Polytechnique, 91128 Palaiseau Cedex, France; and
| | - Patrick Davidson
- Laboratoire de Physique des Solides, Unité Mixte de Recherche 8502, Centre National de la Recherche Scientifique–Université Paris Sud Bât 510, 91405 Orsay Cedex, France
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Rinnert E, Carteret C, Humbert B, Fragneto-Cusani G, Ramsay JDF, Delville A, Robert JL, Bihannic I, Pelletier M, Michot LJ. Hydration of a Synthetic Clay with Tetrahedral Charges: A Multidisciplinary Experimental and Numerical Study. J Phys Chem B 2005; 109:23745-59. [PMID: 16375356 DOI: 10.1021/jp050957u] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The interaction of water with a synthetic saponite clay sample, with a layer charge of 1 per unit cell (0.165 C m(-2)), was investigated by following along water adsorption and desorption in the relative pressure range from 10(-6) to 0.99 (i) the adsorbed amount by gravimetric and near-infrared techniques, (ii) the basal distance and arrangement of water molecules in the interlayer by X-ray and neutron diffraction under controlled water pressure, and (iii) the molecular structure and interaction of adsorbed water molecules by near-infrared (NIR) and Raman spectroscopy under controlled water pressure. The results thus obtained were confronted with Grand Canonical Monte Carlo (GC/MC) simulations. Using such an approach, various well-distinct hydration ranges can be distinguished. In the two first ranges, at low water relative pressure, adsorption occurs on external surfaces only, with no swelling associated. The next range corresponds to the adsorption of water molecules around the interlayer cation without removing it from its position on top of the ditrigonal cavity of the tetrahedral layer and is associated with limited swelling. In the following range, the cation is displaced toward the mid-interlayer region. The interlamellar spacing thus reached, around 12.3 A, corresponds to what is classically referred to as a "one-layer hydrate," whereas no water layer is present in the interlayer region. The next hydration range corresponds to the filling of the interlayer at nearly constant spacing. This leads to the formation of a well-organized network of interlayer water molecules with significant interactions with the clay layer. The structure thus formed leads to a complete extinction of the d001 line in D2O neutron diffraction patterns that are correctly simulated by directly using the molecular configurations derived by GC/MC. The next range (0.50 < P/P0 < 0.80) corresponds to the final swelling of the structure to reach d spacing values of 15.2 A (usually referred to the "two-layer hydrate"). It is associated with the development of a network of liquidlike water molecules more structured than in bulk water. The final hydration range at high relative pressure mainly corresponds to the filling of pores between clay particles.
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Affiliation(s)
- Emmanuel Rinnert
- Agence Nationale pour la gestion des Déchets RAdiocatifs, Parc de la Croix Blanche, 1/7 rue Jean Monnet, 92298 Chatenay Malabry CEDEX, France
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Defontaine G, Michot LJ, Bihannic I, Ghanbaja J, Briois V. Synthesis of NiGa layered double hydroxides. A combined EXAFS, SAXS, and TEM study. 3. Synthesis at constant pH. Langmuir 2004; 20:11213-11222. [PMID: 15568878 DOI: 10.1021/la048681p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The present paper focuses on the direct synthesis of NiGa layered double hydroxides (LDHs) by concomitant addition of Ni and Ga chloride in solution with NaOH solution, at a constant pH value of 6.5. Various Ni/Ga ratios (Ni/Ga = 2, Ni/Ga = 4, or Ni/Ga = 6) were investigated, and samples were collected after successive additions. Each sample was then analyzed by small-angle X-ray scattering (SAXS) to derive information about the shape of the objects formed upon synthesis. In parallel Ni K-edge and Ga K-edge extended X-ray absorption fine structure (EXAFS) analysis were carried out on relevant samples to obtain information on the local structure of the species in suspension. SAXS curves reveal significant changes. At the beginning of the synthesis, for low added volumes (V(s)), the suspension appears to contain both monodimensional and bidimensional objects. For higher V(s), the monodimensional objects disappear and only platelike particles are detected in the suspension. EXAFS results show that all the added gallium atoms are involved in a solid Ni-Ga LDH phase throughout the whole synthesis. In contrast, some nickel cations do not precipitate in the Ni-Ga LDH. At the beginning of the synthesis, for low added volumes they are also involved in the formation of fibrous polycations. For higher added volumes, the fibers are not observed anymore and monomeric nickel species are then present in the suspension.
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Affiliation(s)
- Guillaume Defontaine
- Laboratoire Environnement et Minéralurgie, CNRS INPL ENSG UMR 7569, BP 40, 54501 Vandoeuvre lès Nancy, France.
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Michot LJ, Bihannic I, Porsch K, Maddi S, Baravian C, Mougel J, Levitz P. Phase diagrams of Wyoming Na-montmorillonite clay. Influence of particle anisotropy. Langmuir 2004; 20:10829-10837. [PMID: 15568830 DOI: 10.1021/la0489108] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Natural Na-Wyoming montmorillonite was size fractionated by successive centrifugation. Polydisperse particles with average sizes of 400, 290, and 75 nm were then obtained. As the structural charge of the particles belonging to three fractions (determined by cationic exchange capacity measurements) is the same, such a procedure allows studying the effect of particle anisotropy on the colloidal phase behavior of swelling clay particles. Osmotic stress experiments were carried out at different ionic strengths. The osmotic pressure curves display a plateau whose beginning systematically coincides with the sol/gel transition determined by oscillatory stress measurements. The concentration corresponding to the sol/gel transition increases linearly with particle anisotropy, which shows that the sol/gel transition is not directly related to an isotropic/nematic transition of individual clay particles. Indeed, a reverse evolution should be observed for an I/N transition involving the individual clay particles. Still, when observed between crossed polarizer and analyzer, the gel samples exhibit permanent birefringent textures, whereas in the "sol" region, transient birefringence is observed when the samples are sheared. This suggests that interacting clay particles are amenable to generate, at rest and/or under shear, large anisotropic particle associations.
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Affiliation(s)
- Laurent J Michot
- Laboratoire Environnement et Minéralurgie, UMR 7569 CNRS-INPL-ENSG, 15 Avenue du Charmois, BP 40 54501 Vandoevre Cedex, France.
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Defontaine G, Michot LJ, Bihannic I, Ghanbaja J, Briois V. Synthesis of NiGa layered double hydroxides. A combined EXAFS, SAXS, and TEM study. 2. Hydrolysis of a Ni2+/Ga3+ solution. Langmuir 2004; 20:9834-9843. [PMID: 15491222 DOI: 10.1021/la048652e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Takovites are nickel-based layered double hydroxides (LDH) with a general formula that can be written as Ni(1-x)Al(x)(OH)2, A(z-)(x/z), yH(2)O, where A is a compensating interlayer anion. As in some other LDH samples, the positive charge of the layer can be adjusted upon synthesis and various anions can be exchanged in the interlayer region. It is then important to understand the synthesis pathway of these materials. We then undertook a study on the hydrolytic behavior of pure Ni salts and mixtures of Ni and Ga salts. This paper focuses on the hydrolysis of Ni(2+) and Ga(3+) ions, together in solution, carried out by base addition. The samples will be defined by their hydrolysis ratio R = [OH(-)]/([Ni(2+)] + [Ga(3+)]). Small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM) were used to obtain information on the colloidal species size and shape on a large scale. Each hydrolyzed sample was also studied by Ni K-edge and Ga K-edge extended X-ray absorption fine structure (EXAFS) to obtain information on the local structure of the species in suspension. SAXS curves reveal the presence of bidimensional objects whatever the R values. The platelets formed for R values >/=1.1 are slightly thicker and smaller in size, which may be linked to their different natures. Complementary information is provided by TEM analysis: the first colloids formed have a structure very close to that of alpha-GaOOH, as shown by electronic diffraction. Those structures are progressively replaced by Ni-Ga LDH platelets with increasing hydrolysis ratio, which are the only species in suspension for R = 2.0, as shown by XRD. EXAFS results confirm the complete hydrolysis of gallium before the formation of Ni-Ga LDH phases.
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Affiliation(s)
- Guillaume Defontaine
- Laboratoire Environnement et Minéralurgie (LEM), CNRS INPL ENSG UMR 7569, BP 40, 54501 Vandoeuvre lès Nancy, France.
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Abstract
The solid phase geometry of a Na- and Ca-montmorillonite has been investigated by using ultra-small- and small-angle X-ray scattering and X-ray diffraction. The scattering domain covered by combining these techniques corresponds to characteristic distances ranging from a few angstroms to a micrometer. The intensity scattered on the whole scattering domain was decomposed into two terms, (i) one assigned to the structure of layers' stacks and (ii) one ascribed to the porous network resulting from the entanglement of individual platelets. The comparison of experimental data with theoretical simulations revealed that the stacks of clay layers are complex and heterogeneous. Ordered stacks of approximately 10 layers separated by 9.5 Å seem to be organized in larger particles comprising around 100 layers. Distances between 25 and 150 Å were observed within those particles. Both samples possess a low pore volume fraction of about a few percent, with pores characterized by a highly anisotropic shape. Copyright 2001 Academic Press.
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Affiliation(s)
- Isabelle Bihannic
- Laboratoire Environnement et Minéralurgie, INPL-ENSG-CNRS UMR 7569, 15, Avenue du Charmois, Vandoeuvre Cedex, 54501, France
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