56 research outputs found
Deltaic and Coastal Sediments as Recorders of Mediterranean Regional Climate and Human Impact Over the Past Three Millennia
International audienc
Soap-free emulsion polymerization of poly (methyl methacrylate-co-butyl acrylate): effects of anionic comonomers and methanol on the different characteristics of the latexes
Dynamiques sédimentaires d'avant-cÎte en Bretagne occidentale
The mechanism and evolution of coastal shoreface and beach accumulations is highly dependent on cross-shore andalongshore sediment transport. However, if the shoreface is sometimes integrated in the reflections, its application to the management of coastal risks remains strongly limited due to the lack of validation of theoretical concepts.The research aims to better understand morphodynamic evolution of the coastal sedimentary accumulations at the scale of western Brittany, focusing on two major approaches: 1) the assessment of the theoretical depth of closure of the littoral cell, from an innovative approach ; 2) the morphodynamic analysis of shoreface accumulations of 4 study sites representative of the coast, based on bathymetric, seismic and sedimentary data, previous and newly acquired.The most significant result of theoretical depth of closure approach is the possibility of transport and deposition of sand particles at depths greater than 100 m in the most hydrodynamically intense areas, which implies the possibility of interconnections between hydro-sedimentary cells, through bypassing of headlands and crossing over rocky outcrops. The morphodynamic analysis at the scale of the study sites showed that the evolution of the shoreface with trends of erosion for the enclosed coves and accumulation for the open bays are controlled by the structural morphology of the study sites. Furthermore, the connection between the beach and the shoreface appear complex, and induced by the structural context, the wave climate and the tide. The results of this study highlight the importance of regular combined surveys of the beach and shoreface in the framework of the coastline and the coastal management projects.Les transferts sĂ©dimentaires qui opĂšrent entre la plage et lâavant-cĂŽte, constituent une des causes clairement identifiĂ©es des Ă©volutions positives (accrĂ©tion) et nĂ©gatives (Ă©rosion) de la cellule littorale aux Ă©chelles saisonniĂšre Ă pluridĂ©cennale. Cependant, si cet espace de mobilitĂ© sĂ©dimentaire de lâavant-cĂŽte est parfois intĂ©grĂ© dans les rĂ©flexions, son application Ă la gestion des risques cĂŽtiers reste fortement limitĂ©e faute de validation des concepts thĂ©oriques et de mesures de terrain. Ces travaux visent Ă mieux comprendre le fonctionnement du systĂšme sĂ©dimentaire dâavant-cĂŽte Ă lâĂ©chelle de la Bretagne occidentale, en privilĂ©giant deux axes dâĂ©tude : i) la dĂ©termination de la profondeur de fermeture thĂ©orique de la cellule littorale, Ă partir dâune approche novatrice ; ii) lâanalyse morphodynamique des accumulations dâavant-cĂŽte de 4 sites dâĂ©tudes reprĂ©sentatifs du type de cĂŽte. Cette approche est basĂ©e sur lâanalyse de donnĂ©es bathymĂ©triques, sismiques et sĂ©dimentaires, antĂ©rieures et nouvellement acquises. Les calculs thĂ©oriques de la profondeur de fermeture ont montrĂ© la possibilitĂ© de transferts sĂ©dimentaires opĂ©rants Ă plus de 100 m de profondeur sur toute la plateforme interne et des effets de contournement de caps entre des cellules sĂ©dimentaires sĂ©parĂ©es par des promontoires rocheux. LâĂ©tude Ă lâĂ©chelle des sites dâĂ©tude, a mis en avant que les Ă©volutions morphodynamiques du compartiment de lâavant-cĂŽte sont notamment contrĂŽlĂ©es par la morphologie structurale avec une tendance Ă lâĂ©rosion pour les anses enclavĂ©es et Ă lâaccumulation pour les baies ouvertes. De plus, les liens entre la plage et lâavant-cĂŽte apparaissent complexes, et induits par le caractĂšre enclavĂ© ou non des sites dâĂ©tude, le climat des houles et la marĂ©e. Les rĂ©sultats de cette Ă©tude soulignent lâimportance de rĂ©aliser des suivis rĂ©guliers conjoints de la plage et de lâavant-cĂŽte dans le cadre de projets de gestion du trait de cĂŽte et du littoral
ChemInform Abstract: Differences in the Conformational Behavior of the Potent and Selective, Tyr-D-Thr-Gly-Phe-Leu-Thr(OtBu) and of the inactive Tyr-D-Thr(OtBu)-Gly-Phe-Leu-Thr ÎŽ-Opioid Ligands Evidenced by 1H NMR.
Dynamiques sédimentaires d'avant-cÎte en Bretagne occidentale
The mechanism and evolution of coastal shoreface and beach accumulations is highly dependent on cross-shore andalongshore sediment transport. However, if the shoreface is sometimes integrated in the reflections, its application to the management of coastal risks remains strongly limited due to the lack of validation of theoretical concepts.The research aims to better understand morphodynamic evolution of the coastal sedimentary accumulations at the scale of western Brittany, focusing on two major approaches: 1) the assessment of the theoretical depth of closure of the littoral cell, from an innovative approach ; 2) the morphodynamic analysis of shoreface accumulations of 4 study sites representative of the coast, based on bathymetric, seismic and sedimentary data, previous and newly acquired.The most significant result of theoretical depth of closure approach is the possibility of transport and deposition of sand particles at depths greater than 100 m in the most hydrodynamically intense areas, which implies the possibility of interconnections between hydro-sedimentary cells, through bypassing of headlands and crossing over rocky outcrops. The morphodynamic analysis at the scale of the study sites showed that the evolution of the shoreface with trends of erosion for the enclosed coves and accumulation for the open bays are controlled by the structural morphology of the study sites. Furthermore, the connection between the beach and the shoreface appear complex, and induced by the structural context, the wave climate and the tide. The results of this study highlight the importance of regular combined surveys of the beach and shoreface in the framework of the coastline and the coastal management projects.Les transferts sĂ©dimentaires qui opĂšrent entre la plage et lâavant-cĂŽte, constituent une des causes clairement identifiĂ©es des Ă©volutions positives (accrĂ©tion) et nĂ©gatives (Ă©rosion) de la cellule littorale aux Ă©chelles saisonniĂšre Ă pluridĂ©cennale. Cependant, si cet espace de mobilitĂ© sĂ©dimentaire de lâavant-cĂŽte est parfois intĂ©grĂ© dans les rĂ©flexions, son application Ă la gestion des risques cĂŽtiers reste fortement limitĂ©e faute de validation des concepts thĂ©oriques et de mesures de terrain. Ces travaux visent Ă mieux comprendre le fonctionnement du systĂšme sĂ©dimentaire dâavant-cĂŽte Ă lâĂ©chelle de la Bretagne occidentale, en privilĂ©giant deux axes dâĂ©tude : i) la dĂ©termination de la profondeur de fermeture thĂ©orique de la cellule littorale, Ă partir dâune approche novatrice ; ii) lâanalyse morphodynamique des accumulations dâavant-cĂŽte de 4 sites dâĂ©tudes reprĂ©sentatifs du type de cĂŽte. Cette approche est basĂ©e sur lâanalyse de donnĂ©es bathymĂ©triques, sismiques et sĂ©dimentaires, antĂ©rieures et nouvellement acquises. Les calculs thĂ©oriques de la profondeur de fermeture ont montrĂ© la possibilitĂ© de transferts sĂ©dimentaires opĂ©rants Ă plus de 100 m de profondeur sur toute la plateforme interne et des effets de contournement de caps entre des cellules sĂ©dimentaires sĂ©parĂ©es par des promontoires rocheux. LâĂ©tude Ă lâĂ©chelle des sites dâĂ©tude, a mis en avant que les Ă©volutions morphodynamiques du compartiment de lâavant-cĂŽte sont notamment contrĂŽlĂ©es par la morphologie structurale avec une tendance Ă lâĂ©rosion pour les anses enclavĂ©es et Ă lâaccumulation pour les baies ouvertes. De plus, les liens entre la plage et lâavant-cĂŽte apparaissent complexes, et induits par le caractĂšre enclavĂ© ou non des sites dâĂ©tude, le climat des houles et la marĂ©e. Les rĂ©sultats de cette Ă©tude soulignent lâimportance de rĂ©aliser des suivis rĂ©guliers conjoints de la plage et de lâavant-cĂŽte dans le cadre de projets de gestion du trait de cĂŽte et du littoral
Dynamiques sédimentaires d'avant-cÎte en Bretagne occidentale
The mechanism and evolution of coastal shoreface and beach accumulations is highly dependent on cross-shore andalongshore sediment transport. However, if the shoreface is sometimes integrated in the reflections, its application to the management of coastal risks remains strongly limited due to the lack of validation of theoretical concepts.The research aims to better understand morphodynamic evolution of the coastal sedimentary accumulations at the scale of western Brittany, focusing on two major approaches: 1) the assessment of the theoretical depth of closure of the littoral cell, from an innovative approach ; 2) the morphodynamic analysis of shoreface accumulations of 4 study sites representative of the coast, based on bathymetric, seismic and sedimentary data, previous and newly acquired.The most significant result of theoretical depth of closure approach is the possibility of transport and deposition of sand particles at depths greater than 100 m in the most hydrodynamically intense areas, which implies the possibility of interconnections between hydro-sedimentary cells, through bypassing of headlands and crossing over rocky outcrops. The morphodynamic analysis at the scale of the study sites showed that the evolution of the shoreface with trends of erosion for the enclosed coves and accumulation for the open bays are controlled by the structural morphology of the study sites. Furthermore, the connection between the beach and the shoreface appear complex, and induced by the structural context, the wave climate and the tide. The results of this study highlight the importance of regular combined surveys of the beach and shoreface in the framework of the coastline and the coastal management projects.Les transferts sĂ©dimentaires qui opĂšrent entre la plage et lâavant-cĂŽte, constituent une des causes clairement identifiĂ©es des Ă©volutions positives (accrĂ©tion) et nĂ©gatives (Ă©rosion) de la cellule littorale aux Ă©chelles saisonniĂšre Ă pluridĂ©cennale. Cependant, si cet espace de mobilitĂ© sĂ©dimentaire de lâavant-cĂŽte est parfois intĂ©grĂ© dans les rĂ©flexions, son application Ă la gestion des risques cĂŽtiers reste fortement limitĂ©e faute de validation des concepts thĂ©oriques et de mesures de terrain. Ces travaux visent Ă mieux comprendre le fonctionnement du systĂšme sĂ©dimentaire dâavant-cĂŽte Ă lâĂ©chelle de la Bretagne occidentale, en privilĂ©giant deux axes dâĂ©tude : i) la dĂ©termination de la profondeur de fermeture thĂ©orique de la cellule littorale, Ă partir dâune approche novatrice ; ii) lâanalyse morphodynamique des accumulations dâavant-cĂŽte de 4 sites dâĂ©tudes reprĂ©sentatifs du type de cĂŽte. Cette approche est basĂ©e sur lâanalyse de donnĂ©es bathymĂ©triques, sismiques et sĂ©dimentaires, antĂ©rieures et nouvellement acquises. Les calculs thĂ©oriques de la profondeur de fermeture ont montrĂ© la possibilitĂ© de transferts sĂ©dimentaires opĂ©rants Ă plus de 100 m de profondeur sur toute la plateforme interne et des effets de contournement de caps entre des cellules sĂ©dimentaires sĂ©parĂ©es par des promontoires rocheux. LâĂ©tude Ă lâĂ©chelle des sites dâĂ©tude, a mis en avant que les Ă©volutions morphodynamiques du compartiment de lâavant-cĂŽte sont notamment contrĂŽlĂ©es par la morphologie structurale avec une tendance Ă lâĂ©rosion pour les anses enclavĂ©es et Ă lâaccumulation pour les baies ouvertes. De plus, les liens entre la plage et lâavant-cĂŽte apparaissent complexes, et induits par le caractĂšre enclavĂ© ou non des sites dâĂ©tude, le climat des houles et la marĂ©e. Les rĂ©sultats de cette Ă©tude soulignent lâimportance de rĂ©aliser des suivis rĂ©guliers conjoints de la plage et de lâavant-cĂŽte dans le cadre de projets de gestion du trait de cĂŽte et du littoral
Dynamiques sédimentaires d'avant-cÎte en Bretagne occidentale
The mechanism and evolution of coastal shoreface and beach accumulations is highly dependent on cross-shore andalongshore sediment transport. However, if the shoreface is sometimes integrated in the reflections, its application to the management of coastal risks remains strongly limited due to the lack of validation of theoretical concepts.The research aims to better understand morphodynamic evolution of the coastal sedimentary accumulations at the scale of western Brittany, focusing on two major approaches: 1) the assessment of the theoretical depth of closure of the littoral cell, from an innovative approach ; 2) the morphodynamic analysis of shoreface accumulations of 4 study sites representative of the coast, based on bathymetric, seismic and sedimentary data, previous and newly acquired.The most significant result of theoretical depth of closure approach is the possibility of transport and deposition of sand particles at depths greater than 100 m in the most hydrodynamically intense areas, which implies the possibility of interconnections between hydro-sedimentary cells, through bypassing of headlands and crossing over rocky outcrops. The morphodynamic analysis at the scale of the study sites showed that the evolution of the shoreface with trends of erosion for the enclosed coves and accumulation for the open bays are controlled by the structural morphology of the study sites. Furthermore, the connection between the beach and the shoreface appear complex, and induced by the structural context, the wave climate and the tide. The results of this study highlight the importance of regular combined surveys of the beach and shoreface in the framework of the coastline and the coastal management projects.Les transferts sĂ©dimentaires qui opĂšrent entre la plage et lâavant-cĂŽte, constituent une des causes clairement identifiĂ©es des Ă©volutions positives (accrĂ©tion) et nĂ©gatives (Ă©rosion) de la cellule littorale aux Ă©chelles saisonniĂšre Ă pluridĂ©cennale. Cependant, si cet espace de mobilitĂ© sĂ©dimentaire de lâavant-cĂŽte est parfois intĂ©grĂ© dans les rĂ©flexions, son application Ă la gestion des risques cĂŽtiers reste fortement limitĂ©e faute de validation des concepts thĂ©oriques et de mesures de terrain. Ces travaux visent Ă mieux comprendre le fonctionnement du systĂšme sĂ©dimentaire dâavant-cĂŽte Ă lâĂ©chelle de la Bretagne occidentale, en privilĂ©giant deux axes dâĂ©tude : i) la dĂ©termination de la profondeur de fermeture thĂ©orique de la cellule littorale, Ă partir dâune approche novatrice ; ii) lâanalyse morphodynamique des accumulations dâavant-cĂŽte de 4 sites dâĂ©tudes reprĂ©sentatifs du type de cĂŽte. Cette approche est basĂ©e sur lâanalyse de donnĂ©es bathymĂ©triques, sismiques et sĂ©dimentaires, antĂ©rieures et nouvellement acquises. Les calculs thĂ©oriques de la profondeur de fermeture ont montrĂ© la possibilitĂ© de transferts sĂ©dimentaires opĂ©rants Ă plus de 100 m de profondeur sur toute la plateforme interne et des effets de contournement de caps entre des cellules sĂ©dimentaires sĂ©parĂ©es par des promontoires rocheux. LâĂ©tude Ă lâĂ©chelle des sites dâĂ©tude, a mis en avant que les Ă©volutions morphodynamiques du compartiment de lâavant-cĂŽte sont notamment contrĂŽlĂ©es par la morphologie structurale avec une tendance Ă lâĂ©rosion pour les anses enclavĂ©es et Ă lâaccumulation pour les baies ouvertes. De plus, les liens entre la plage et lâavant-cĂŽte apparaissent complexes, et induits par le caractĂšre enclavĂ© ou non des sites dâĂ©tude, le climat des houles et la marĂ©e. Les rĂ©sultats de cette Ă©tude soulignent lâimportance de rĂ©aliser des suivis rĂ©guliers conjoints de la plage et de lâavant-cĂŽte dans le cadre de projets de gestion du trait de cĂŽte et du littoral
ChemInform Abstract: ETHYL POLYPHOSPHATE, PREFERRED REAGENT FOR THE SYNTHESIS OF METHYLATED DERIVATIVES OF BENZO(B)FURAN-2,3-DICARBOXYLATE
Hydrogen bonded supramolecular polymers in protic solvents: role of multitopicity
International audienceWe describe the synthesis of macromolecular amphiphiles of various molar masses containing well-defined hydrophobic groups incorporating urea moieties. All compounds have the same proportion of associative hydrophobic groups and solubilising POE chains. However, a strong influence of both 10the number of associative groups per chain and its polydispersity is demonstrated. In water, where the interactions between stickers are strong, the monomer (bearing a single sticker) self-assembles into filaments, but all other compounds with more than one sticker per chain are 15insoluble. In methanol, where the interactions between stickers are weaker, neither the monomer nor the monodispersed dimer are assembled, whereas polydispersed chains with an average number of stickers per chain of 2 or 3 self-assemble into filaments, leading to macroscopic gelation
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