Dissertations / Theses on the topic 'Interface fluxes'
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Krueger, Kathryn Marie. "Metal fluxes across the sediment water interface in a drinking water reservoir." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/90297.
Master of Science
In many drinking water reservoirs, elevated concentrations of metals, such as iron (Fe) and manganese (Mn), pose a challenging water quality problem. Elevated metal concentrations affect taste, color, and odor in drinking water and can be expensive to treat for. The presence of Fe and Mn in water is influenced by the oxygen concentrations in the water. When oxygen levels in the water are high, Fe and Mn are not soluble in water. However, when the oxygen levels in water are low, Fe and Mn can be released from soils, sediments and rocks into water and can thus pose a concern for drinking water quality. Many water utilities have installed systems to increase oxygen concentrations in drinking water reservoirs with the goal of maintaining low levels of metals in water supplies. However, previous research has shown that even when oxygenation systems are operational, Fe and Mn can still be released into water from the reservoir’s bottom sediments. To examine the factors that contribute to the release of metals from the sediments into the water column, I measured the rate of release of Fe and Mn from the sediments into the water column at a local drinking water reservoir (Falling Creek Reservoir, Vinton, VA). I conducted the experiments twice during summer 2018 using chambers that isolated the water immediately above the sediments. During the experiments, I monitored how Fe and Mn concentrations changed over time under different oxygen conditions. In addition to the measurements, I also used a mass balance method using water column data to estimate the metal release. Overall, results showed that release rates are highly variable during the summer months, with some periods having positive rates (releasing metals from sediments into the water column) and some with negative rates (returning metals from the water column to sediment). The metal release rate are highly sensitive to oxygen conditions in the water column, at the sediment-water interface and in the sediments. When used together, these two methods provide a useful tool for constraining metal release rates under different oxygen conditions. This research will help drinking water plant managers to improve the effectiveness of oxygenation systems and water quality management practices related to Fe and Mn. Additionally, this research will help improve the water quality for residents and can be applied to other lakes and reservoirs where metal concentrations are elevated.
Couto, Vanessa Barcelos. "Fluxos de amônia e óxido nitroso na interface ar-água do sistema lagunar de Maricá-Guarapina." Niterói, 2017. https://app.uff.br/riuff/handle/1/3604.
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Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ
Este estudo analisa os fluxos de óxido nitroso (N 2 O) e amônia (NH 3 ) no Sistema Lagunar de Maricá-Guarapina (SLMG). O N 2 O é um dos gases do efeito estufa e está envolvido no consumo de ozônio (O 3 ) na estratosfera. A NH 3 pode levar a acidificação de ambientes terrestres e aquáticos, a eutrofização de sistemas aquáticos e produção de N 2 O. O SLMG vem sofrendo degradação da qualidade de suas á guas devido à urbanização e às atividades agropecuárias na região. Este sistema la gunar é composto por quatro lagoas interligadas entre si através de canais: Maricá, Ba rra, Padre e Guarapina. Para a análise de N 2 O foi utilizada a técnica da câmara estática flutua nte e 4 modelos de predição de fluxos (MPF). No caso da NH 3 foram feitas estimativas de fluxos também através de MPF. Os resultados deste estudo mostram que as quatro lagoa s do SLMG apresentam comportamentos distintos com relação aos fluxos dos dois gases ana lisados. As estimativas de taxas de emissão do sistema lagunar mostram que, apesar do sistema a presentar lagoas que parecem atuar como sorvedouro de N 2 O ou de NH 3 , num balanço geral, ele emite N para a atmosfera s ob uma ou outra forma. A taxa de emissão estimada variou entr e 92,15 g N dia -1 e 104,77 g N dia -1 . Outra informação que esta estimativa trouxe foi a d e que a maior parte das emissões ocorre sob a forma de NH 3 com emissão estimada de 84,79 g N dia -1 a 97,41 g N dia -1 .
This study examines the nitrous oxide (N 2 O) and ammonia (NH 3 ) fluxes in Maricá- Guarapina’s system. The N 2 O is a greenhouse gas and is involved in the consum ption of the ozone (O 3 ) in the stratosphere. The NH 3 can lead to acidification of terrestrial and aquat ic environments, eutrophication of aquatic systems and production of N 2 O. The SLMG is suffering degradation in the water’s quality due to urbanization and agricultural activities in the region. This system is composed for four lagoon interconnected between themselves through channels: Maricá, Barra, Father and Guarapi na. For the analysis of N 2 O was used the technique of the static chamber and 4 models predic tion fluxes (MPF). In the case of NH 3 were made estimates of fluxes through MPF too. The results of this study show that the four lagoons in the SLMG have different behaviors with r espect to the fluxes of the two gases analyzed. Estimates of the rates of emission in th e system lagoon show that despite the present system lagoons that seem act as sink of N 2 O and NH 3 , in a general balance, it gives N to the atmosphere in one form or another. The estim ated emission rate ranged between 92,15 g N -1 day -1 and 104,77 g N -1 day -1 . Other information that brought this estimate was that the majority of emissions occur in the form of NH 3 with estimated emission of 84,79 g N -1 day -1 to 97,41 g N -1 day -1 .
Couceiro, F. "A comparison of nutrient fluxes across the sediment-water interface at two intertidal sites in Strangford Lough." Thesis, Queen's University Belfast, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431539.
Knobloch, Amanda. "Fluxes, drivers, and composition of carbon exchanged at the Taskinas Creek, VA coastal marsh creek-estuarine interface." W&M ScholarWorks, 2019. https://scholarworks.wm.edu/etd/1582642587.
Bryant, Lee Davis. "Dynamic forcing of oxygen, iron, and manganese fluxes at the sediment-water interface in lakes and reservoirs." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/77337.
Ph. D.
Murniati, Erni [Verfasser], and Andreas [Akademischer Betreuer] Lorke. "Physical-biological interactions controlling the variability of oxygen fluxes across the sediment-water interface / Erni Murniati ; Betreuer: Andreas Lorke." Landau : Universität Koblenz-Landau, Campus Landau, 2018. http://d-nb.info/1154434567/34.
Read, Deborah J. "The role of labile dissolved organic carbon in influencing fluxes across the sediment-water interface : from marine systems to mine lakes." University of Western Australia. School of Environmental Systems Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0144.
Cambra, Rémi. "Etude des flux turbulents à l'interface air-mer à partir de données de la plateforme OCARINA." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLV024/document.
Exchanges of heat and momentum at the air-sea interface play a major role in the formation and the dynamics of water and air masses. In spite of decades of research, we still need to improve our knowledge of these exchanges, and more specifically our knowledge of turbulent fluxes, which are key variables in meteorological and climate models. In these models, sub-grid turbulent processes, thus turbulent fluxes also have to be modeled, which is mostly done with the Monin-Obukhov (1954, MOS hereafter) similarity theory. However, on the one hand, the use of a model implies that coefficients have to be adjusted. On the other hand, the model itself may require improvements. Unfortunately, obtaining flux estimates that have a good accuracy is a challenging effort, because of the intrusive effect of the platform, the limited accuracy the instruments, and because the instruments have their own sampling volume.Our study focuses on the estimation of turbulent fluxes at sea from measurements made with the new OCARINA platform (autonomous trimaran) during two campaigns : STRASSE 2012 and AMOP 2014. We analyze the characteristics of turbulence in the surface boundary layer, we estimate the turbulent fluxes by different methods, and compare the values of fluxes depending on environmental conditions, taking into account the sea state
Burton, Evans Jessica Landis. "The effect of benthic microalgal photosynthetic oxygen production on nitrogen fluxes across the sediment-water interface in a shallow, sub-tropical estuary." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2998.
Thesis research directed by: Marine, Estuarine, Environmental Sciences Graduate Program. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
BONSIGNORE, Maria. "The biogeochemical cycle of mercury in the Augusta Bay." Doctoral thesis, Università degli Studi di Palermo, 2014. http://hdl.handle.net/10447/91305.
Schonsky, Horst Georg [Verfasser], Andre [Akademischer Betreuer] Peters, Gerd [Gutachter] Wessolek, and Jörg [Gutachter] Bachmann. "Energy and water fluxes at the soil atmosphere interface of water repellent soils / Horst Georg Schonsky ; Gutachter: Gerd Wessolek, Jörg Bachmann ; Betreuer: Andre Peters." Berlin : Technische Universität Berlin, 2015. http://d-nb.info/1156272963/34.
Cambra, Rémi. "Etude des flux turbulents à l'interface air-mer à partir de données de la plateforme OCARINA." Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLV024.
Exchanges of heat and momentum at the air-sea interface play a major role in the formation and the dynamics of water and air masses. In spite of decades of research, we still need to improve our knowledge of these exchanges, and more specifically our knowledge of turbulent fluxes, which are key variables in meteorological and climate models. In these models, sub-grid turbulent processes, thus turbulent fluxes also have to be modeled, which is mostly done with the Monin-Obukhov (1954, MOS hereafter) similarity theory. However, on the one hand, the use of a model implies that coefficients have to be adjusted. On the other hand, the model itself may require improvements. Unfortunately, obtaining flux estimates that have a good accuracy is a challenging effort, because of the intrusive effect of the platform, the limited accuracy the instruments, and because the instruments have their own sampling volume.Our study focuses on the estimation of turbulent fluxes at sea from measurements made with the new OCARINA platform (autonomous trimaran) during two campaigns : STRASSE 2012 and AMOP 2014. We analyze the characteristics of turbulence in the surface boundary layer, we estimate the turbulent fluxes by different methods, and compare the values of fluxes depending on environmental conditions, taking into account the sea state
Wen, Yuan [Verfasser], Edzo [Akademischer Betreuer] [Gutachter] Veldkamp, Heinz [Gutachter] Flessa, and Reinhard Pd [Gutachter] Well. "Gross N2O fluxes across soil-atmosphere interface and stem N2O emissions from temperate forests / Yuan Wen ; Gutachter: Edzo Veldkamp, Heinz Flessa, Reinhard Pd Well ; Betreuer: Edzo Veldkamp." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2017. http://d-nb.info/1132813077/34.
Torres, Olivier. "Représentation des flux turbulents à l’interface air-mer et impact sur les transports de chaleur et d’eau dans un modèle de climat." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLV002/document.
The turbulent fluxes at the air-sea interface represent the link between the ocean and the atmosphere and therefore play a major role in the climate system. In climate models, turbulent processes are subgrid scale processes, not explicitly resolved, and must therefore be parameterized. They are estimated from atmospheric and oceanic state variables using mathematical models called “bulk parameterizations”. This thesis aims to characterize and understand the links between the representation of turbulent fluxes at the air-sea interface and the behavior of a climate model at different time scales in tropical regions. To study these links, I developed a modeling strategy using an atmospheric 1D model (SCM), an oceanic (OGCM) or atmospheric (AGCM) general circulation model and a coupled model (GCM). The analysis of SCM simulations allows us to study the direct response of a model to modifications of the turbulent fluxes parameterization. It is shown that it regulates the amount of water, energy and momentum available to the system and therefore its behavior. It can thus represent more than 60% of simulated latent heat flux differences between two climate models in convective periods. The spatial impact of the parameterization of turbulent fluxes is studied through AGCM simulations. They highlight the link between parameterization, its effect on large-scale moisture and temperature gradients, and thus its influence on atmospheric circulation. The study of OGCM simulations underlines the main role of the wind for the behavior of the tropical oceans. If the wind drives changes in SST due to its impact on ocean dynamics and mainly on the equatorial undercurrent, humidity, temperature and radiative flux only influence the ocean surface and are therefore of lesser importance. Finally, the analysis of GCM simulations highlights the feedbacks and the adjustment generated by the modification of turbulent fluxes. When coupling the two components, the ocean acts as a buffer and absorbs the modification of the turbulent fluxes, which leads to a modification of the SST. The adjustment that occurs causes a modification of the atmospheric variables which leads to a new state of equilibrium of the system. The parameterization of surface turbulent fluxes acts at first order on the energy equilibrium of a coupled model and can therefore lead to different simulated climate state. Since this study is focused on the tropics, an interesting perspective would be to extend the study of the turbulent fluxes representation to other spatio-temporal scales (i.e. extra-tropical areas / daily frequency). This would make it possible to validate the systematic behavior of the parameterizations defined in this thesis on a global scale
Matos, Christiene Rafaela Lucas de. "Biogeoquímica de águas intersticiais e estimativa de fluxos de nutrientes na interface água-sedimento em áreas costeiras do estado do Rio de Janeiro." Niterói, 2016. https://app.uff.br/riuff/handle/1/1575.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências-Geoquímica. Niterói, RJ
A diagênese recente de metais-traço redox-sensitivos, nutrientes e produtos metabólicos (Mn, Fe, ΣNO3-, NH4+, PO43-, SO42-, ΣH2S, sílica dissolvida (SiD), e alcalinidade) nas águas intersticiais e os fluxos de ΣNO3-, NH4+, PO43- e SiD na interface água-sedimento (IAS) foram estudados em três ambientes que representam cenários diferentes de aportes antrópicos da zona costeira do estado do Rio de Janeiro, incluindo a Baía de Cabo Frio (CF), a Enseada de Jurujuba (JU) e a Baía de Sepetiba (SE). As razões C:N:P e as assinaturas isotópicas (13C e 15N) dos sedimentos indicaram que a MO é de origem marinha no testemunho CF e JU. Já em SE ocorre matéria orgânica (MO) de origem marinha e terrestre, havendo predominância de origem fitoplanctônica. As concentrações de COT demonstraram similaridades no acúmulo do material orgânico entre a BC e a SE, enquanto JU apresentou concentrações mais altas. Os padrões de distribuição das zonas redox dentro da coluna sedimentar, baseado nos perfis de água intersticial, nos ambientes estudados mostraram serem influenciados pela variabilidade do teor de COT e processos de bioturbação e/ou físicos. Na CF, sob condições subóxicas, as principais reações redox foram bem identificadas nos sedimentos superficiais e seguiu a sequência teórica do consumo oxidante: ΣNO3->MnO2>Fe(OH)3, a zona de redução de SO42- não foi evidenciada nesse perfil. Na JU, sob condições anóxicas, os perfis de água intersticial indicaram um zoneamento redox “comprimido”, favorecendo a contração das zonas óxica-subóxica e expansão da região sulfídrica. As altas concentrações de alcalinidade, amônio e sulfeto indicaram degradação intensiva de matéria orgânica no testemunho JU, dominado pela zona de redução de sulfato e uma influência menor pela das reduções de ΣNO3-, MnO2 e Fe(OH)3. Na SE, sob condições subóxicas e a presença de macrofauna observada no sedimento, duas sequências diagenéticas sobrepostas foram observadas. A primeira sequência envolveu a redução do NO3-, MnO2 e Fe(OH)3. A segunda sequência diagenética envolveu a redução do MnO2 e Fe(OH)3. A presença de duas sequências diagenéticas pode estar relacionada aos efeitos de bioturbação e/ou outras perturbações físicas, como eventos de dragagem em áreas adjacentes e atividades de embarcações que causam ressuspensão do sedimento. A ocorrência de variação da concentração de COT no topo do testemunho SE, ressalta a perturbação do sedimento. Foi evidenciado que os fluxos de NO3- e NH4+ em CF são influenciados pelos processos de desnitrificação, em JU pelo processo de desnitrificação e redução desassimilatória de nitrato para amônio, já em SE pelos processos de desnitrificação e nitrificação. O fluxo do PO43- foi afetado pela precipitação de mineral autigênico e bioturbação do sedimento. E o fluxo de SiD foi afetado pela gradual dissolução de sílica biogênica com o aumento da profundidade. Em JU foram observados os maiores fluxos de NO3-, NH4+ e SiD na IAS. No entanto, o fluxo de PO43- mais alto foi observado na IAS da Baía de Sepetiba, provavelmente devido às baixas concentrações de PO43- encontradas na água de fundo em relação às outras áreas de estudo
The early diagenesis of the redox-sensitive trace metals, nutrients, metabolic products (Mn, Fe, ΣNO3-, NH4+, PO43-, SiD, SO42-, H2S and alcalinity) in pore waters and the fluxes of the ΣNO3-, NH4+, PO43- and DSi at the sediment-water interface (SWI) were studied in three environments that represent different scenarios of anthropogenic inputs of the coastal zone of the state of Rio de Janeiro, including the Cabo Frio Bay (CF), Jurujuba Sound (JU) and Sepetiba Bay (SE). The C:N:P ratios and isotopic signatures (13C and 15N) of the sediments indicated that organic matter (OM) is of marine origin in CF and JU core. In SE occurs OM marine and terrestrial origin, with predominance of phytoplankton origin. The TOC concentrations have demonstrated similarities in the accumulation of organic material between BC and SE, while JU submitted higher concentrations. The distribution patterns of redox zones within the sedimentary column, based on pore water profiles, in the studied environments showed to be influenced by the variability of the TOC content and bioturbation and/or physical processes. In CF, under suboxic conditions, the main redox reactions have been identified in surface sediments and followed the theoretical result of oxidant consumption: ΣNO3-> MnO2> Fe (OH)3, the SO42- reduction zone was no evidence in this profile. In JU, under anoxic conditions, the pore water profiles indicated a redox zone ‘compressed’, favoring the contraction of the oxic-suboxic zones and expansion of sulfidic region. The high concentrations of alkalinity, ammonium and sulfide indicated intensive degradation of OM in JU core dominated by the sulfate reduction zone and a smaller influence by the ΣNO3-, MnO2 and Fe (OH)3 reductions. In SE, under suboxic conditions and with the observed presence of macrofauna in the sediment, two overlapped diagenetic sequences can be observed. The first sequence involved the reduction of ΣNO3-, MnO2 and Fe (OH)3. The second diagenetic sequence involved the reduction of MnO2 and Fe (OH)3. The presence of two diagenetic sequences may be related to effects bioturbation and/or other physical disturbances, such as dredging events in adjacent areas and craft activities that cause sediment resuspension. The occurrence of variation of TOC concentration at the top of the SE core, emphasizes the disturbance of sediment. It was evidenced that the fluxes of ΣNO3- and NH4+ in CF are influenced by denitrification processes, in the JU by process denitrification and nitrate dissimilatory reduction to ammonium, as in SE by nitrification and denitrification processes. The PO43- fluxes was affected by the precipitation of autigenic mineral and bioturbation of the sediment. And the SiD flux is affected by the gradual dissolution of biogenic silica with increasing depth. In JU were observed larger fluxes of ΣNO3-, NH4+ and DSi at the SWI were observed. However, the higher PO43- fluxes was observed at the SWI Sepetiba Bay, probably due to low concentrations of PO43- found in the overlying water in relation to other areas of study.
Deldicq, Noémie. "Evaluation expérimentale du comportement de déplacement des foraminifères benthiques : implications dans les processus de remaniement sédimentaire des écosystèmes intertidaux." Electronic Thesis or Diss., Université de Lille (2018-2021), 2021. http://www.theses.fr/2021LILUR019.
The aim of this PhD is to describe the role of benthic foraminifera in bioturbation processes focusing on particulate fluxes at the sediment-water interface. Specifically, the objectives are fourfold: (i) characterising the motion behaviour of key benthic foraminiferal species inhabiting intertidal mudflats from the Eastern English Channel at the sediment water interface to further classify them into functional groups of bioturbation, (ii) quantifying surface sediment reworking rates of the above-mentioned species, (iii) understanding how biotic and abiotic parameters may drive the mode and the intensity of surface sediment reworking of the dominant species Haynesina germanica, and (iv) further describing the vertical burrowing dynamics and the biogenic structures built by Haynesina germanica to quantify its bioturbation rates. To do so, the following parameters are described: the travelled distance, the velocity, the vertical position, the activity level and the tortuosity of the path. The motion-behaviour is described for the following species: Haynesina germanica, Cribroelphidium williamsoni, Quinqueloculina seminulum, Ammonia tepida and Miliammina fusca. Although they are all classified in the functional group of biodiffusors, these species differ in their preferential vertical position within the sediment. Specifically, C. williamsoni is an epifaunal-biodiffusor, Q. seminulum, M. fusca and H. germanica are gallery-biodiffusors while A. tepida is a surficial biodiffusor. This therefore means that the mode of sediment reworking is species-specific in benthic foraminifera. Its intensity is mediated by specific traits as well as biotic and abiotic factors. Indeed, travelled distance, velocity, activity level and tortuosity of the path would vary between and within species. As a consequence, the rate and the mode of sediment reworking are species-, individual- and functional group-dependant. Specifically, the surface area of the test, the species density, the temperature and the organic matter concentration are key parameters that control the bioturbation activity of H. germanica. The present work highlights the role of benthic foraminifera in sediment reworking processes taking place at the sediment-water interface and in the sediment column. It opens new perspectives on the understanding of the ecology of foraminifera and their putative non-negligible role in bioturbation processes in intertidal ecosystems
Alibert, Clément. "Contrôles physiques, chimiques et biologiques des flux de gaz à l'interface sol-atmosphère." Thesis, Université Paris sciences et lettres, 2020. http://www.theses.fr/2020UPSLE014.
Mastering gas fluxes from the soil to the atmosphere is important for several high-stakes societal issues. Measuring and extrapolating these fluxes is a complex exercise due to their spatial and temporal variability. This variability is related to the many, often intertwined, processes that control the transport of gases in soils and at the soil-atmosphere interface. An innovative device has been developed within an experimental platform to study gas fluxes at the surface of a soil column placed under controlled conditions, with long-term, high-resolution monitoring of many parameters. The physical, chemical and biological mechanisms responsible for the variations of gas flux at the soil-atmosphere interface can thus be studied separately. This study focused in particular on the effects of plant metabolism (evapotranspiration, respiration and photosynthesis) as well as water content and barometric pressure. These mechanisms affect the pressure gradient that controls advective gas transport. A constant gas flow at the base of a soil can thus show significant transient variations on time scales ranging from several hours to several days. Numerical modelling has been initiated although no code is currently able to account for two-phase transport in the presence of sharp air/water fronts and evaporation. The numerous experimental results will be used to validate the necessary developments
Torres, Olivier. "Représentation des flux turbulents à l’interface air-mer et impact sur les transports de chaleur et d’eau dans un modèle de climat." Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLV002.
The turbulent fluxes at the air-sea interface represent the link between the ocean and the atmosphere and therefore play a major role in the climate system. In climate models, turbulent processes are subgrid scale processes, not explicitly resolved, and must therefore be parameterized. They are estimated from atmospheric and oceanic state variables using mathematical models called “bulk parameterizations”. This thesis aims to characterize and understand the links between the representation of turbulent fluxes at the air-sea interface and the behavior of a climate model at different time scales in tropical regions. To study these links, I developed a modeling strategy using an atmospheric 1D model (SCM), an oceanic (OGCM) or atmospheric (AGCM) general circulation model and a coupled model (GCM). The analysis of SCM simulations allows us to study the direct response of a model to modifications of the turbulent fluxes parameterization. It is shown that it regulates the amount of water, energy and momentum available to the system and therefore its behavior. It can thus represent more than 60% of simulated latent heat flux differences between two climate models in convective periods. The spatial impact of the parameterization of turbulent fluxes is studied through AGCM simulations. They highlight the link between parameterization, its effect on large-scale moisture and temperature gradients, and thus its influence on atmospheric circulation. The study of OGCM simulations underlines the main role of the wind for the behavior of the tropical oceans. If the wind drives changes in SST due to its impact on ocean dynamics and mainly on the equatorial undercurrent, humidity, temperature and radiative flux only influence the ocean surface and are therefore of lesser importance. Finally, the analysis of GCM simulations highlights the feedbacks and the adjustment generated by the modification of turbulent fluxes. When coupling the two components, the ocean acts as a buffer and absorbs the modification of the turbulent fluxes, which leads to a modification of the SST. The adjustment that occurs causes a modification of the atmospheric variables which leads to a new state of equilibrium of the system. The parameterization of surface turbulent fluxes acts at first order on the energy equilibrium of a coupled model and can therefore lead to different simulated climate state. Since this study is focused on the tropics, an interesting perspective would be to extend the study of the turbulent fluxes representation to other spatio-temporal scales (i.e. extra-tropical areas / daily frequency). This would make it possible to validate the systematic behavior of the parameterizations defined in this thesis on a global scale
Gangloff, Sophie. "Evaluation of the mechanisms of trace elements transport (Pb, Rare Earth Elements,... ) and the elemental and isotopic fractionation (Ca and Sr) at the interface water-soil-plant." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAH002/document.
This work is focused on the study of a profile of soil and soil solutions collected on an experimental plot covered with spruce. All these samples come from the watershed of the Strengbach (environment - OHGE Hydrogeochimique Observatory), were sampled at different depths (5, 10, 30 and 60 cm) and during the period between 2009 and 2013. Characterizations of soil extracts by infrared spectroscopy allowed to highlight changes in the organic functional groups with depth and that these changes have a significant impact on the behaviour of the cations (major and trace) in the soil. Ultrafiltration experiments helped to identify flows of colloidal and dissolved organic carbon as well as those of the major and trace-element present in soil solutions. The joint use of isotope tracers (87Sr / 86Sr and δ44 / 40 Ca) and chemical (Rare Earth Elements) have highlighted processes taking place at the water-soil-plant interface, as the uptake by root or soil alteration
Tran, Phuoc Nguyen. "Modèles de sélection d'interface et d'association flux/interface pour les terminaux mobiles multi-interfaces." Phd thesis, Télécom ParisTech, 2010. http://pastel.archives-ouvertes.fr/pastel-00564095.
Benusiglio, Adrien. "Indiscrétions aux interfaces." Phd thesis, Ecole Polytechnique X, 2013. http://pastel.archives-ouvertes.fr/pastel-00860739.
Magarelli, Gabriella. "Fluxos de mercurio gasoso na interface solo/atmosfera na Bacia do Rio Negro utilizando camaras dinamicas de fluxo." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249451.
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: Foi objetivo principal deste trabalho de tese a quantificação dos fluxos de mercúrio gasoso (Hg0) na interface solo-atmosfera na Bacia do rio Negro utilizando câmaras dinâmicas de fluxo. O estudo metodológico realizado permitiu verificar que as câmaras de fluxo foram eficientes para comparar os fluxos dos diferentes sítios. No entanto, a umidade dentro da câmara e a baixa vazão de bombeamento podem ter subestimado os valores dos fluxos. Os fluxos encontrados nas áreas de floresta tanto de terra firme quanto inundável foram baixos, em concordância com dados da literatura. Nas áreas de floresta, os fluxos evasivos diurnos (média de 1,3 ± 1,3 pmol m-2 h-1) foram equivalentes aos fluxos invasivos noturnos (média de -1,3 ± 1,2 pmol m-2 h-1) e concluiu-se que os solos de floresta da Bacia não exportam Hg para a atmosfera. O que ocorre é uma ciclagem de cerca de 0,7 t ano-1 de Hg dentro das florestas. A deposição de Hg nos solos das florestas via serapilheira demonstrou ser a via de entrada de Hg mais significativa, cujo valor foi de 26,6 t ano-1. As áreas desmatadas da Bacia do Rio Negro apresentaram valores de fluxos de Hg na interface solo/atmosfera bem maiores que as áreas de floresta (média de 12,3 ± 9,9 pmol m-2 h-1). Isto levou à importante conclusão que a ausência de vegetação aumenta significativamente os fluxos de emissão, tanto em áreas de terra firme quanto em áreas inundáveis. Na bacia do rio Negro, considerando 1% de desmatamento, a massa de Hg exportada para a atmosfera pelos solos desmatados seria de 0,13 t ano-1. Além da importância de se estimar os fluxos de Hg0 na interface solo/atmosfera para o estudo do ciclo biogeoquímico do Hg na Bacia do rio Negro, o entendimento dos fatores que influenciam estes fluxos é de extrema importância. Dentre os fatores ambientais estudados, os que apresentaram uma correlação mais efetiva com os fluxos foram: a temperatura do solo, radiação solar e o teor de matéria orgânica no solo
Abstract: The aim of this thesis was to quantify the soil/air exchange of mercury in the Negro River Basin by using a Dynamic Flux Chamber. The methodological study showed that the flux chamber was efficient to compare the Hg fluxes in the different sites. However, the humidity inside the chamber and the low flushing flow rate could have subestimated the Hg fluxes. Hg fluxes found at the flooding forest and at the non-flooding forest were low but they are in agreement with literature reports. At the forest sites, the evasive diurnal Hg fluxes (mean of 1.3 ± 1.3 pmol m-2 h-1) were equivalent to the nocturnal fluxes (mean of -1.3 ± 1.2 pmol m-2h-1), concluding that the forest soils of the Negro River Basin do not export Hg to the atmosphere.What occurs is a Hg cycling of about 0.7 t y-1 inside the forest. The deposition of Hg to the forests soils from litterfall showed to be the most significative Hg input to the forest, whose value was 26.6 t y-1. The deforested sites of the Negro River Basin presented Hg fluxes in the soil/air exchange higher than the forest sites (12.3 ± 9.9 pmol m-2 h-1). This led to an important conclusion that the absence of vegetal covering significantly enhances Hg soil emissions, both in areas of flooding and in nonflooding soils. At the Negro River Basin, considering 1% of desforestation, the Hg mass exported to the atmosphere from the deforested soils would be 0.13 t ano-1. Besides the importance to estimating the Hg0 fluxes at the air/soil interface for a Hg biogeochemistry study of the Negro River Basin, the understanding of the factors that could affect these Hg fuxes is very important. Among the environmental paramethers studied, the soil temperature, the solar radiation and the soil organic matter were the paramethers which showed the highest correlations with the Hg fluxes. Key-words: mercury fluxes, soil/air exchange, flux chamber, Amazon, soil temperature
Doutorado
Quimica Analitica
Doutor em Ciências
Le, Roux Sébastien. "Effet Marangoni aux interfaces fluides." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S060/document.
We report experiments about the deposition of water soluble surfactants at the interface between two fluids. After some theoretical developments, we study the spreading of water soluble amphiphiles at the water/air interface. In this part, we present two experimental setups where these molecules show a typical induced flow velocity, and a finite spreading distance, depending on the CMC of surfactant we use, which results in the apparition of a coronna on the surface of the liquid. We then set up a fast and simple CMC measurement protocole using our experimental setup. This spreading induces also a vertical deformation of the interface, a double toroidal recirculation in the bulk, and a beatiful hydrodynamic surface instability all around the coronna. The second experiment is about the spreading of amphiphiles at the interface between oil and water. In this experiment, the vertical deformations induced by the spreading can become so important that under certain circumstances, we manage to create a hole in the oil layer. We focus on the study of these vertical deformations and on the caracteristics of this hole. Finally, the last experiment is about the deposition of a Triton X-100 drop at the water/air interface. This molecule has the ability to gelify when it gets hydrated, allowing him to float. Then we can observe the self propulsion of the droplet. We focus on the microscopic structure of this gel phase, and also on the erratic trajectories followed by the drop
Sharma, Preeti. "Coupled electrokinetic fluxes in a single nanochannel for energy conversion." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAY100/document.
Coupled electrokinetic phenomena within nanochannel are of interest for energy harvestingand production of electricity based on the controlled mixing of river water with sea water known as "blue energy". The origin of the phenomena is related to interaction with charged walls and transport of ions within the so called Debye layer. This work aims at a better understanding of the physics and transport phenomena in this layer associated with solution confined in nanochannel.A specific instrumentation has been developed during this thesis to study the mechanisms governing coupled nanofluics fluxes. The idea is to characterize simultaneously the mass transport within the nanochannel and the electrical current driven through the nanochannel by the application of either salinity difference , pressure difference or voltage difference across the channel. The thesis is divided into three parts.In the first part, a custom made flow cell and experimental conditions to control and measure various fluxes is presented. The capability of cell to measure current or voltage under applied pressure or salinity gradient is presented taking the benefit of commercial nanoporous Nafion membrane.The second part is focused on an easy way of preparation of nanochannel sample in the form of single chip, in which nanochannel is interfaced to micro and macroscopic world. A well-controlled, 1.4µm long nanochannel of conical geometry with a maximum aspect ratio of 10 is fabricated. The minimum apex size of nanochannel achieved here is 50 nm which is about 30 times less than the length of channel. The presence of electrode directly at the interface of nano to micro cavity allow to perform electrical characterization of nanochannel with high precision.The third part of the thesis is devoted to the development of a method for the direct measurement of flow rate as low as 10 pL/min across a single nanochannel. This measurement approach combined with electrical measurement, could be used, in presence of pressure, voltage or salinity gradient, to measure the flow rate and the electrical current across a single nanochannel simultaneously and independently
Charru, François. "Stabilite d'une interface entre deux fluides visqueux." Toulouse, INPT, 1991. http://www.theses.fr/1991INPT054H.
Greenall, Martin James. "Covariance principles for fluids at interfaces." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408028.
Barraud, Chloé. "Nanorhéologie de fluides complexes aux interfaces." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAY011/document.
Liquids confined present many fascinating behaviors very different from those observed in their volume. Confinement can induce a shift in the balance of phases (eg the liquid-vapor transition, also called capillary condensation), it can change the glass transition temperature of the polymer, or impose order on the molecular arrangement of fluid. The changes in the mechanical properties of liquid interfaces are particularly important in applications. However the level of understanding, the simple case of Newtonian liquids is still controversial, with one hand, numerical simulations show that the viscosity should not be changed for some higher molecular sizes containment, and secondly non-unanimous experiences, sometimes showing qualitative changes in rheological properties under confinement. Recently we have shown that the methods of hydrodynamic impedance sphere-plane geometry is a privileged, non-intrusive method and unambiguous, to discuss the mechanics of nano-liquid interfaces (1,2). As interphase, ie fluid layers whose properties are modified by the proximity of a solid, it is possible to accede their contactless module, so without the disturbance caused by a second surface.S As regards the effect of confinement on the rheology, we have shown that the elastic deformation across the pico meter of confining surfaces, gives a strong modification beyond apparent rheology of the fluid, even in the absence of any intrinsic effect. The thesis aims to implement the hydrodynamic impedance methods to study the rheology of polymer solutions confined. We specifically consider two models of fundamental importance as well as practical systems: brushes grafted polymer whose mechanical properties are an issue in lubrication applications as well as for biological flows and solutions of water-soluble polymers interest in enhanced oil recovery, in order to understand the effects of thinning containment and to distinguish between changes in viscosity and depletion layer induced by the flow. At the instrumental level, one of the challenges of the thesis is to implement the hydrodynamic impedance measurements on two complementary instruments at the level of the probe: the measuring dynamic power (SFA) of Liphy, and AFM interferometric detection developed at the Institut Néel. These different scales of investigation will help to clarify the medium average mechanical properties of liquids confined and their gradients near the wall. A view of work will be to look mechanical and rheological properties of polymer brushes intrinsic determined directly on SFA or AFM with their functional properties: lubricating properties of sliding contacts, or modification of the flow in microchannels. This will continue on the implementation by Lionel Bureau Liphy experimental platform: SFA friction advised biomimetic micro-fluidic systems (walls functionalized polymer brushes). The challenge will be to understand how the mechanical and rheological properties of brushes determine those systems in which they operate
Salkin, Louis. "Création, stabilité et rupture d'interfaces fluides." Phd thesis, Université Rennes 1, 2014. http://tel.archives-ouvertes.fr/tel-01070794.
Vallabh, Priya. "Electrorheological brake for haptic interface systems." Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/17070.
Bier, Markus. "Interfaces in fluids of charged platelike colloids." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-29509.
Oliveira, Raquel Renó de. "Fluxos de CO2 na interface oceano-atmosfera no Oceano Atlântico Sul subtropical." Instituto Nacional de Pesquisas Espaciais (INPE), 2018. http://urlib.net/sid.inpe.br/mtc-m21c/2018/06.28.19.28.
In this work, were studied the CO2 fluxes at the ocean-atmosphere interface and the meteorological and oceanographic variables that affect them in the subtropical region of the Atlantic Ocean, seeking to understand the main parameters that modulate the behavior of CO2 fluxes between the ocean and the atmosphere. For this purpose, in situ atmospheric and oceanic CO2 concentration data were measured by infrared gas analyzers installed in a bows micrometeorological tower and in the wet laboratory of the Hidro- Oceanographic Vital de Oliveira (H39) research vessel. The data were collected between June 27th and July 15th of 2015, during the oceanographic cruise FORSA (Following Ocean Rings in the South Atlantic). The CO2 fluxes at the ocean-atmosphere interface were calculated from the Eddy Covariance (EC) method and the bulk parameterization method - using Wanninkhof (1992 and 2014) and Takahashi et al. (2009) transfer velocities. Whereas it was a transatlantic oceanographic campaign, where oceanographic and time conditions were very different, the study area was subdivided into four subregions (R1, R2, R3, R4). The results of CO2 fluxes by CV, in general, show that the study area along the ship's trajectory, behaved as a CO2 sink. However, the sub-regions responded differently: (i) R1, on the coast of Africa, acted as a source of CO2; (ii) R2 and R3, open ocean regions, were strongly influenced by local and synoptic oceanographic and meteorological parameters, presenting both sink and sources areas of CO2; (iii) R4, on the coast of Brazil, was the only one with the ideal environmental conditions to act as a CO2 sink. The CO2 fluxes calculated by bulk parameterizations also show that the study area acts as a CO2 sink. The difference founded by comparing the results of the two methods, indicated a need to better understand the ocean contribution in those methods. The results presented here are, to our knowledge, the first description of the CO2 fluxes between the ocean and the atmosphere from micrometeorological measurements in a ship, in the Subtropical South Atlantic Ocean. Thus, it is a significant contribution to the understanding of the biogeochemical processes that occur at the ocean-atmosphere interface in the synoptic time scale.
Fu, Yun. "Linear stability of an interface between two incompressible fluids." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1142955745.
Pierson, Jean-Lou. "Traversée d’une interface entre deux fluides par une sphère." Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/15754/2/Pierson_2_sur_4.pdf.
Osman, S. M. "Theoretical studies of the fluid-fluid interface." Thesis, University of East Anglia, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382833.
Shewring, Nigel Ivor Edward. "Interactions at the clay/polymer/water interface." Thesis, Sheffield Hallam University, 1998. http://shura.shu.ac.uk/20358/.
黃俊祺 and Chun-kay Edward Wong. "Electrorheological fluid interfaces in mechatronic devices." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31237848.
Wong, Chun-kay Edward. "Electrorheological fluid interfaces in mechatronic devices /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1965733X.
Lagarde, Antoine. "Birth, life and death of a granular raft." Thesis, Sorbonne université, 2020. http://www.theses.fr/2020SORUS054.
We study the life of an axisymmetric monolayer of particles called a granular raft floating at an oil-water interface, from its formation to its sinking. We first look at the capillary interaction between a pair of beads, and generalize the result to a pair of granular rafts. The force strongly depends on the number of particles in each raft, a result that we understand by looking at the interfacial deformation each individual raft creates. Then, we explore the interaction between numerous granular rafts of different sizes randomly distributed. The aggregation is faster when the particles are initially more concentrated at the interface. The individual motion of each bead cannot be solved, but the overall clustering can be described statistically. The cluster-size distribution appears to answer to a self-similar evolution that we characterize. After that, we focus on the structural changes a granular raft can experience during its motion, and more precisely to its erosion. The cohesion of an entire raft is far higher than expected by the usual capillary theory. The same high cohesion is found between two beads in contact. A precise description of the position of the contact line accounts for the unexpectedly high resistance to erosion. Finally, we explore the dynamics of sinking of a granular raft, which happens when the vertical deflection of the interface exceeds a critical deformation. The oil thread formed during the sinking thins following an unusual path between the two classical self-similar regimes, delaying the onset of the final regime. This result emphasizes the decisive role boundary conditions can play in the transition between self-similarities
Nania, Samantha Lynn. "Spectroscopic analysis of molecular fluids at the solid-liquid interface." Diss., University of Iowa, 2017. https://ir.uiowa.edu/etd/5972.
Ferchichi, Yassine. "Etude expérimentale du mouvement d'une particule sphérique à l'approche d'une interface liquide/fluide." Phd thesis, Ecole Centrale Paris, 2013. http://tel.archives-ouvertes.fr/tel-01001954.
Tsoneva, Yana. "L'organisation moléculaire de l'eau liquide à l'interface avec des fluides apolaires." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2016. http://www.theses.fr/2016ENCM0007/document.
The structuring of water molecules at the water/vapour interface is an object of scientific interest for decades. Most of the existing theoretical studies are focused on bulk water but there is still need of a more detailed research on surface water. In addition, interfaces with alkanes are interesting as being instructive from both biological and industrial perspectives. Since in both bio- and industrial applications water/air and water/oil interfaces are mediated by amphiphiles, the role of a surfactant monolayer on surface water structuring deserves more attention as well.In the present Ph. D. thesis several atomistic water models were chosen and classical molecular dynamics simulations were carried out on bulk water, water/vapour and water/alkane (from pentane to nonane) systems, as well as on water/DLPC/vapour and water/DLPC/octane models, DLPC being dilauroyl phosphatidylcholine. In all cases the temperature was kept at 298 K. Several structural properties of bulk and surface water layers were examined by means of radial distribution functions and Voronoi diagrams. Dipole moments, surface tension and hydrogen bonding were tackled too. The objective was to estimate the impact of accounting for polarisability on the water properties of interest and to select a cost-efficient water model for describing them, as well as to add new data to the existing knowledge about interfacial water structuring.The study addresses the water structuring in bulk and surfacial water at the interface with vapour or alkanes of different chain length. One of the aims of the work was to assess the reproducibility of experimental data using an assortment of polarisable and non-polarisable water models and to check for which properties the utilisation of polarisable models is critical. Simple polarisable models based on Drude oscillators were tested in order to keep the computational costs low. For bulk water and water/vapour systems the models TIP4P, SWM4-NDP and COS/G2 performed the best. Since the TIP4P model produced results commeasurable with the polarisable ones, it was used predominantly further on to simulate water/alkane (C5-C9) interface and to quantify the structural parameters of water obtained from RDFs and Voronoi analyses. The molecules in this layer are organised in a more compact and less ordered manner. The ordering is owed mainly to hydrogen bonds which are twice as many in the bulk compared to the surface. The analysis of the Voronoi diagrams showed that the tetrahedral coordination was blurred and more complex polyhedra were formed. The surface layer was found to consist of two sublayers, inner and outer, with oppositely oriented unequal polarity, defining areas of residual charges at the interface.In addition to the systems with direct contact between water and non-polar fluids, interfaces mediated by lipid monolayers were modelled. The monolayer was meant to seam together the two phases. The compactness of the surfacial water, which was enhanced by the presence of alkanes, was tightened further by the lipid introduction. However, the water orientation was changed and the surfacial polarity was inverted, balanced by the lipid heads instead of the diffuse outer sublayer.The main contributions of the Ph.D. thesis are as follows:1. It is shown that the usage of a polarisable water model is not necessary for correct evaluation of a number of properties, but is critical for characteristics such as dipole moments and surface tension.2. For the first time a structural analysis has been made using Voronoi diagrams and an assortment of water models which demonstrates the difference between bulk and surfacial characteristics of liquid water.3. An original contribution is the study of a solid-condensed DLPC monolayer at the water/vapour interface utilising different water models and at the interface of water/octane, considering the limited experimental data available
Lachouette, Damien. "Modélisation d'une interface fluide/solide avec érosion : application à l'érosion interne." Phd thesis, Université du Sud Toulon Var, 2009. http://tel.archives-ouvertes.fr/tel-00643226.
Lachouette, Damien. "Modélisation d'une interface fluide/solide avec érosion : application à l'érosion interne." Phd thesis, Toulon, 2009. https://theses.hal.science/tel-00643226/fr/.
The erosion is a major cause of failure in the hydraulic structures such as levees and dams. The territory has more than 10000 km of dikes, resulting in an important issue in terms of flood risk. A more general approach is essential to a good understanding of phenomena. Modeling mechanisms of erosion must develop solutions to secure the books and make them less susceptible to these phenomena. This work is devoted to modeling the evolution of an interface between a soil domain and a flow domain. The movement of this interface is governed by soil erosion driven by the flow. The flow is calculated by the Stokes equations with a penalty term for the unified representation of the behavior of the two domains. In a first part, we address the issue of representation of erosion. The second part deals more specifically with the unified representation of behavior settings, including the use of penalty methods. The third part is a review of the main methods of interface capture. A detailed description of the Level Set method is given. In the fourth section, , we discuss the numerical solution of flow equations. The fifth section brings together all of the testing method. The last part is devoted to applying the model in three cases: the "Hole Erosion Test", the phenomenon of suffusion and the erosion of river bed around a bridge pier
Osborn, William R. "Statics and dynamics of interfaces in multi-phase fluids." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318759.
Huber, Grégory. "Modélisation des effets d'interpénétration entre fluides au travers d'une interface instable." Phd thesis, Aix-Marseille Université, 2012. http://tel.archives-ouvertes.fr/tel-00833037.
Albert, Fabrice. "Stabilité d'une interface entre deux fluides cisaillés : étude numérique et asymptotique." Toulouse, INPT, 1996. http://www.theses.fr/1996INPT126H.
Saiseau, Raphael. "Thermo-Hydrodynamique dans les systèmes critiques : instabilités, relaxation et évaporation." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0184.
To form a drop at the tip of a liquid column, a pinching process has to occur until it reaches the atomic scale at the final break-up, covering all length scales. Some recent experimental and theoretical results show that this common phenomenon is still poorly understood when the pinching reaches the thermal fluctuations length scales. Here, we try to deepen our understanding by using phase separated near-critical binary liquids as model of fluctuating liquids and interfaces and by looking at different relaxation dynamics of out of equilibrium situations: instability of a liquid column, interface relaxation and droplet evaporation. Hence, the study of these phenomena is performed using ultra-soft liquid interfaces and continuously varying hydrodynamic, thermodynamic and stochastic properties with the shift to the critical temperature. In a first step, the interface of these near-critical binary liquids is initially driven out of equilibrium using the radiation pressure of a laser wave in order to create in situ liquid columns and droplets. Dedicated tools for image analysis of near-critical fluctuating fluids were also developed. Then, we show that, contrary to the classical idea, liquid ligaments break-up triggered by Rayleigh-Plateau instability comes from modes superposition. This enables us, using Fourier analysis, to build the full dispersion relation for spontaneous break-up. Secondly, a preliminary work on drop spreading on solid surface established the existence of two dynamical regimes: one nonlinear relaxation mechanism to a spherical cap followed by an auto-similarity behavior of this spherical cap characteristic of Tanner’s spreading. A significant amount of evaporation was also observed in some spreading dynamics, calling for a work extension considering adapted models. A last study was performed on single droplet evaporation. It constitutes the first experimental work on conserved order parameter evaporation, furthermore for near-critical binary liquids. Against all odds, the measured evaporation and droplet rising dynamics seem completely unfit when using diffusion and gravity coupling descriptions. In particular, their behaviors are independent to the proximity to critical point. All these behaviors are verified over a large variation of distances to the critical point. As such, they seem to be universal within the criticality meaning. Eventually, the hydrodynamic behavior are verified when the thermodynamic one stay misunderstood. This raises questions on their coupling by means of thermal fluctuations. Nonetheless, thanks to the developed tools, we are now able to simultaneously get the macroscopic scale of the dynamics and the microscopic scale of interface fluctuations opening the way to more complete, multi-scale, analyses, in the fluctutations dominated case of the already observed phenomena
Gay, Cyprien. "Nanorhéologie et autres problèmes de polymères aux interfaces." Phd thesis, Université Pierre et Marie Curie - Paris VI, 1997. http://tel.archives-ouvertes.fr/tel-00921712.
Zouaoui, Driss. "Equilibre des liquides magnétiques avec interface libre." Vandoeuvre-les-Nancy, INPL, 1991. http://www.theses.fr/1991INPL022N.
Thiéry, Régis. "Les systèmes eau-gaz-sels : modélisation des équilibres de phases et application aux fluides géologiques." Vandoeuvre-les-Nancy, INPL, 1996. http://docnum.univ-lorraine.fr/public/INPL_T_1996_THIERY_R.pdf.