Дисертації з теми "Extraction racinaire de l'eau"
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Albasha, Rami. "Evaluation de la productivité de l’eau d’irrigation par la modélisation : le cas du maïs sous goutte-à-goutte enterré en sol limoneux profond." Electronic Thesis or Diss., Paris, AgroParisTech, 2015. http://www.theses.fr/2015AGPT0025.
Повний текст джерелаThe "more crop per drop" paradigm is behind considerable efforts to increasing the productivity of water consumed in irrigated agriculture. In this context, the evaluation of the agronomic performances of irrigation techniques and their ability to reduce the water consumption is a prerequisite for optimizing water use in irrigated agriculture. This thesis explores the potentials of Subsurface Drip Irrigation (SDI) within a modeling framework to evaluate its agronomic performance under various soil and climatic contexts.Many crop models allow today the prediction of crop yields as a function of, inter alia, the climatic conditions, the type of soil, the availability of water, of nutrient, and agricultural practices. These crop models usually couple the water and solute transfer processes in the soil to crop development. The water uptake of plant roots plays herein a key role of joining the processes in soil to those of the plant.Despite the strong spatial and temporal variability of the activity of root uptake, this activity is often presented in crop models with empirical “static” functions: the spatial distribution of water uptake depends on a predefined distribution of root density, but not on the type of irrigation. These empirical functions are found to be suitable for the simulation of root uptake when water is brought to the surface (sprinkler irrigation, gravity, etc.). However, their legitimacy under drip irrigation remains to be demonstrated.This thesis evaluates the performance of the empirical approaches for modeling root water uptake under drip irrigation, with the ultimate objective of introducing a simple crop model suitable for this technique.From the one hand, the role of the function defining the spatial distribution of root density is explored. Numerical simulations supported by field experiments allowed analyzing the phenomenon of "compensatory water uptake", which is exacerbated under localized irrigation. Considering this phenomenon in modeling was necessary for adequately predicting water consumption of the crop, the distribution of water in the soil, and especially drainage fluxes under SDI.From the other hand, the findings from the first study are taken into account in the development of SDICM, Subsurface Drip Irrigation Crop Model. SDICM is couples bidirectional water transfer process in the soil to crop growth. This model was confronted with field observations which allowed putting forward the importance of root water uptake process in the prediction of water profiles in cropped soils.Finally, an application example was conducted where the water productivity of maize under different pedo-climatic conditions was assessed using SDICM and a capacitive type model. The purpose of the comparison is to highlight the importance of simulating bidirectional soil-water transfer in the context of SDI
Vercambre, Gilles. "Modelisation de l'extraction de l'eau par une architecture racinaire en condition de disponibilite hydrique non uniforme. Etude sur pechers en verger." Paris, Institut national d'agronomie de Paris Grignon, 1998. http://www.theses.fr/1998INAP0046.
Повний текст джерелаPetigny, Loïc. "L'eau dans tous ses états comme solvant alternatif pour l'éco-extraction du végétal." Thesis, Avignon, 2014. http://www.theses.fr/2014AVIG0252.
Повний текст джерелаThe use of innovative extraction technologies is of outmost importance in the cosmetic industry. This process step is consuming large amounts of energy and materials. Furthermore, some solvents used are not benign. Some of them are from oil products. In order to better preserve the environment and human health, we must find alternatives to solvents and conventional extraction methods. To pursue this goal, we will use water as solvent and innovative technologies to create new extraction methods of natural products. The work presented in this thesis first establishes a review of extraction methods. All those methods, old as well as new ones, are specific in terms of target matrix or extracted molecules. Then, we focused on a mature extraction method: hydrodistillation. The simultaneous extraction and separation of water soluble compounds as well as volatile compounds from boldo leaves (Peumus boldus, Mol.), is undertaken with the help of microwaves. The parameters optimization leads to a pilot scale-up. The intensification and continuous mode transition of the ultrasound assisted extraction of boldo leaves is then studied. Afterwards, we studied the maturing method of surfactant addition to water. This is in order to extract hydrophilic and hydrophobic compounds of rosemary (Rosmarinus officinalis L.). Finally, we explored an extraction method still in R&D. This method use only water in order to extract hydrophobic compounds of sweet orange peels ( Citrus sinensis L.) with a microwave device
Bobille, Hélène. "Modulation de l’exsudation racinaire de composés azotés chez les Fabacées et réponse aux stress hydriques." Thesis, Angers, 2016. http://www.theses.fr/2016ANGE0067.
Повний текст джерелаLegume roots release substantial amounts of nitrogen (N) into the soil. They can help to reduce the use of synthetic N fertilisers in cropping systems. A part of this N derives from root exudates, mainly in amino acids (AAs) forms, that are highly suspected to regulate the abundance of microbial community in the rhizosphere. This may impact plant nutrition and resistance to abiotic stress. However, exudated AAs have not been unequivocally quantified, due to interaction with rhizosphere microorganisms and mineral particles. We hypothesized that root AA exudation could change significantly according to the substrate type, the plant growth and water availability. In the present work, we have developed a methodology using unsterilized soil in order to measure the rhizosphere AA fingerprint (RAAF), as the net result of interactions between AA exudation and rhizospheric environment. The RAAF was measured in Medicago truncatula grown in either sterilized sand or unsterilized soil, at three vegetative plant stages; and in Pisum sativum grown in unsterilized soil, under either a water deficit or a water excess. P. sativum plants were stem-labeled with 15N, in order to assess root 15N-AA released in the rhizosphere. The RAAF increased substantially during plant growth, showing a significant quantitative and qualitative plant growth dependent effect. Water deficit significantly modified RAAF with more recently assimilated N, proline, alanine and valine released in the rhizosphere under water deficit. This work contributed to highlight factors affecting RAAF and to better understand ecophysiological aspects of N rhizodeposition of legumes
Srayeddin, Iyad. "Transferts hydriques sol-plante et extraction racinaire : une approche de la spatialisation des prélèvements hydriques par tomographie de résistivité électrique." Avignon, 2009. http://www.theses.fr/2009AVIG0617.
Повний текст джерелаA better knowledge of the functioning of water uptake by plant roots is necessary in order to optimize agricultural water resources management. To this respect, the understanding of the acquisition of soil water by root systems is an important objective of agronomical research. However, characterization of water transfer in the soil-plant system and the spatialization of water uptake at the field scale are still problematic and challenging. Soil - plant environment is a complex system, varying in time and space. The depletion of soil water in the rooted zone is controlled by soil, plant and climatic factors. In order to spatialize the water uptake at the plant’s population scale, methodologies and proxy variable allowing an estimation of water extraction and its variability are highly needed. This would reflect simultaneously the overall and spatial heterogeneity of the population and its growing medium. To this aim, we used the Electrical Resistivity Tomography (ERT) as an alternative approach to the classical methods of water measurements (local soil water balance) for estimating root water uptake. ERT results in a spatial estimation of soil electrical resistivity, the latter being related to the variability of soil water content. 2D or 3D imaging of soil electrical resistivity and its variations with time are related to water content variations as well as water extraction distribution in soil. This experimental study aims at evaluating ERT for spatializing water uptake at the field scale with various plants and different levels of water availability. Three types of plant (Maize, Sorghum and Broad bean) were selected because they exhibit different root systems morphologies and /or and water extraction capacities. These crops were subjected in the field to three levels of water availability ranging from rain fed to full irrigation. Water extraction and its variability, at the field scale, was estimated firstly by a “direct” approach which empirically links the temporal difference in soil electrical resistivity and the uptake. Secondly, an “indirect” more general approach, using in situ calibration between soil electrical resistivity and water content into a spatialized water balance calculation has been used. The water uptake images resulting from these estimations show high spatial and temporal variation of water uptake. The estimation of root water uptake at field scale by ERT is thus possible. However, this spatial estimation can be more or less severely restricted by different constraints which are related to: ERT sensitivity (decrease of ERT sensitivity with depth, accuracy of the in situ water content-resistivity calibration relationship: RMSE ~ 0. 03 cm3. Cm-3), the type of ERT measurement setup (decrease of resolution with depth with a surface array) and to the environmental conditions (problems for ERT measurements in dry and clay soil: decrease of soil-electrode contact and increase of soil heterogeneity due to soil cracking). This work contributes to a first methodological step, showing the possible use of ERT for spatializing and quantifying the spatial variations of root water uptake, if soil hydrodynamic data are available. More globally, this work traces new developments in the understanding of the spatial heterogeneity of root water uptake in relation with soil properties and root system growth
Tournier, Pierre-Henri. "Absorption de l'eau et des nutriments par les racines des plantes : modélisation, analyse et simulation." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066030/document.
Повний текст джерелаIn the context of the development of sustainable agriculture aiming at preserving natural resources and ecosystems, it is necessary to improve our understanding of underground processes and interactions between soil and plant roots.In this thesis, we use mathematical and numerical tools to develop explicit mechanistic models of soil water and solute movement accounting for root water and nutrient uptake and governed by nonlinear partial differential equations. An emphasis is put on resolving the geometry of the root system as well as small scale processes occurring in the rhizosphere, which play a major role in plant root uptake.The first study is dedicated to the mathematical analysis of a model of phosphorus (P) uptake by plant roots. The evolution of the concentration of P in the soil solution is governed by a convection-diffusion equation with a nonlinear boundary condition at the root surface, which is included as a boundary of the soil domain. A shape optimization problem is formulated that aims at finding root shapes maximizing P uptake.The second part of this thesis shows how we can take advantage of the recent advances of scientific computing in the field of unstructured mesh adaptation and parallel computing to develop numerical models of soil water and solute movement with root water and nutrient uptake at the plant scale while taking into account local processes at the single root scale
BARTHES, LAURE. "Role du nitrate sur le transfert de l'eau et des composes azotes du xylene de plantules de mais et de ble en condition de poussee racinaire applications agronomiques." Paris 11, 1994. http://www.theses.fr/1994PA112448.
Повний текст джерелаGuérin, Loïc. "Devenir des polluants inorganiques contenus dans les résidus de combustion des déchets ménagers : spéciation et élaboration de tests de mobilité en vue de leur stockage ou de leur valorisation." Toulon, 2000. http://www.theses.fr/2000TOUL0005.
Повний текст джерелаOne ton of incinerated municipal solid wastes give about 300kg of bottom ash and 50kg of APC (Air Pollution Control) residues which are mainly constituted of oxides and silico-aluminate compounds. A non-negligible part of these residues are soluble compounds (NaCl, KCl, CaCl2, CaSOa,. . . ) and heavy metals (Cd, Pb, Zn. . . . ) which are harmful elements in view of their disposal or valorisation. We first characterized the composition of the residues and the physico-chemical mechanisms in case of lixiviation. Sequential extractions have been used to define the speciations of heavy metals and major constituents. Heavy metals are mainly-associated with calcite and anhydrite and these mineral compounds are soiubilised in acid conditions. These extractions were associated with pH-stat extractions to predict the behaviour of the residues in time. We then used simple scenarios and simulations : in the case of n on-exceptional conditions of disposal, the chlorides ate the first compounds which are released to the environment. The carbonatation phenomenon in open air quickly reduced (some months) the pH of the residues leachate to about pH=8. 5, which is fortunately, in most cases the pH of the minimum solubilisation of heavy metals. A kinetic approach confirms this result. The rain is then the only possible source of protons and the decrease of the leachates pH proceeded very slowly (about hundreds of thousand years). The remaining metals, associated with oxides or inside the alumino-silicate mould, cannot be released to the environment, except under special conditions of disposal
Bakti, Jos. "Récupération d'acides malique et tartrique par extraction liquide-liquide. Application à la dépollution d'effluents agro-industriels." Toulouse, INPT, 1993. http://www.theses.fr/1993INPT009G.
Повний текст джерелаSmagghe, Freddy. "Séparation des acides tartrique et malique par extraction liquide-liquide. Valorisation et dépollution des effluents viti-vinicoles." Toulouse, INPT, 1991. http://www.theses.fr/1991INPT040G.
Повний текст джерелаGeoffroy, Thibaud. "Valorisation de l'écorce d'érable rouge et d'érable à sucre : optimisation de la production d'extraits à l'eau chaude et caractérisation de leur potentiel antioxydant." Doctoral thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/34940.
Повний текст джерелаRésidu généré en fortes quantités par l’industrie forestière, l’écorce est principalement valorisée par combustion pour la production d’énergie. Pourtant, des projets de bioraffineries sont en développement croissant pour proposer de nouvelles voies de valorisation telle que l’extraction. L’écorce pouvant contenir des molécules extractibles potentiellement bioactives en quantités appréciables, les industries agro-alimentaire, cosmétique et pharmaceutique s’intéressent de près à de telles initiatives. Cette vaste gamme de composés bioactifs propose en effet des alternatives séduisantes à des ingrédients de synthèse de moins en moins prisés. De tels extractibles démontrant des activités antioxydantes, antibactériennes, anti-cancer ou encore anti-inflammatoires ont été isolés au sein de l’écorce des deux essences d’érables, Acer rubrum L. (érable rouge) et Acer saccharum Marsh. (érable à sucre). Ces hétérosides phénoliques ainsi que d’autres extractibles d’intérêt sont susceptibles d’être extraits à l’eau, un solvant vert apprécié pour des applications finales ayant trait à la santé humaine. La thèse présentée s’intéresse donc à la valorisation de l’écorce de l’érable rouge et de l’érable à sucre par récupération et caractérisation d’extractibles hydrosolubles potentiellement antioxydants. Le premier axe de la recherche est centré sur l’optimisation d’un procédé d’extraction à l’eau chaude. En variant les paramètres de granulométrie de l’écorce, de température, de durée de l’extraction et de ratio écorce/solvant, le but a été d’obtenir des valeurs optimales de rendement, teneur en phénols totaux, capacité antioxydante et consommation énergétique estimée. Partant des résultats obtenus, les conditions suivantes : granulométrie de 250–500 μm, température de 90°C, durée de 1 h, ratio écorce/solvant de 1/10, ont été jugées pertinentes pour une mise à l’échelle. Ainsi, des traitements post-extraction ont été investigués à échelle laboratoire pilote pour la production d’extraits secs. Combinant plusieurs méthodes de concentration (osmose inverse, évaporation sous vide) et de séchage (atomisation, lyophilisation), ces traitements ont été évalués selon différentes variables réponses : récupération de l’extrait, capacité antioxydante, teneurs en protéines, en composés phénoliques, en sucres totaux et énergie nécessaire aux opérations unitaires des différents procédés. Pour les extraits des deux essences d’érable, les combinaisons osmose inverse/atomisation et osmose inverse/lyophilisation se sont avérées les plus prometteuses. De qualité supérieure en termes d’antioxydants phénoliques, l’extrait d’écorce d’érable rouge lyophilisé a été choisi pour l’investigation de tels composés par criblage antioxydant. L’approche basée sur des techniques couplant test antioxydant in vitro au radical DPPH et séparation chromatographique par HPLC a permis de mieux comprendre les mécanismes radicalaires en présence des dérivés galloyl-glucitols de l’érable rouge. Le phénomène d’auto-oxydation mis en évidence chez ces dérivés testés purs n’a pas été observé lorsque ceux-ci ont été évalués dans des mélanges tertiaires ou directement dans l’extrait. L’effet de mixture/matrice associé à ce comportement a orienté la suite des travaux vers l’étude de fractions de composés plutôt que vers l’isolement de composés purs. Pour cela, la technique d’ultrafiltration a été investiguée pour la production de fractions concentrées. Ce dernier volet a donc permis d’explorer des classes de composés peu, voire non étudiés au sein des deux érables (protéines, tannins). Même si les résultats demeurent préliminaires, la caractérisation des tannins a révélé certaines similarités chez les deux essences, à savoir la présence de tannins de type proanthocyanidine en quantités comparables. En termes de différences, contrairement à l’érable à sucre, l’érable rouge semble riche en gallotannins de hautes masses moléculaires. Toutefois, des analyses complémentaires seraient nécessaires pour confirmer ce résultat. Au final, cette thèse fournit une base substantielle pour l’établissement d’une voie de valorisation viable des extractibles des écorces d’érable rouge et d’érable à sucre. Elle propose un défrichage des principales problématiques intrinsèques à la production d’extraits pour des applications alimentaire, cosmétique ou pharmacologique. Si les connaissances des composés présents dans l’écorce d’érable ont été améliorées, de nombreuses étapes restent nécessaires à la création d’une filière de bioraffinerie pérenne. Pour aller dans ce sens, la suite de la recherche prévoit, entre autres, des tests de toxicité et d’activités in vivo, ainsi que l’étude de l’intégration des extraits dans des matrices alimentaires.
Bark is a high-volume residue from the forest industry that is mostly incinerated for its calorific value. However, biorefineries are increasingly gaining importance by providing new alternatives, such as solvent extraction. As bark is usually rich in extractives susceptible to exhibit bioactivities, agro-food, cosmetic and pharmaceutical industries keep a close eye on such opportunities. This high diversity of bioactive natural compounds in extracts provides a valuable substitute to synthetic ingredients, currently losing popularity. Phenolic extractives associated to antioxidant, antibacterial, anti-cancer or anti-inflammatory activities have been found in red maple (Acer rubrum L.) and sugar maple (Acer saccharum Marsh.) bark. In addition to other promising extractives, these phenolic glycosides could be recovered using water. This non-toxic extraction solvent is usually privileged for human-health related applications. This thesis investigates the valorisation of red maple and sugar maple bark by recovery and antioxidant characterisation of their water-soluble extractives. First, the research was focused on hot-water extraction optimisation. By varying several parameters (particle size of bark, extraction temperature and duration, bark/solvent ratio), optimal values were determined in terms of extraction yield, phenolic content, antioxidant capacity and estimated energy consumption. From these results, a 250–500 μm particle size, 90°C temperature, 1 h duration and a 1/10 bark/water ratio were found relevant for a scale-up. Therefore, post-extraction treatments were investigated at semi-pilot scale aiming to produce dry extracts. Combining concentration (reverse osmosis, vacuum evaporation) and drying (spray-drying, freeze-drying) methods, treatments were evaluated based upon several response variables: extract recovery, antioxidant capacity, protein, phenolic and carbohydrate contents and power consumption induced by the operation units of the process. In regards to these variables, extracts from both maple species seemed more potent when processed using reverse osmosis, associated to spray-drying or freeze-drying. The higher potential in terms of antioxidant phenolics determined for the red maple bark extract obtained using reverse osmosis and freeze-drying led us to perform antioxidant screening on this extract. An approach based on in vitro DPPH radical scavenging test associated to HPLC separation allowed for a better understanding of radical scavenging mechanisms related to galloyl-glucitol derivatives from red maple. Autoxidation of these compounds tested individually was not observed when evaluated in a tertiary mixture or in the crude extract. This mixture/matrix effect helped us define the next step as a study focusing rather on the production of fractions than on the isolation of pure compounds. To this end, ultrafiltration was studied as a tool for extract fractionation. Thus, this last part of the project allowed us to explore different classes of compounds in both sugar and red maple (proteins, tannins), which have rarely been studied. Although preliminary, the obtained results indicated the similarities between the characteristics of tannins found in both species i.e. proanthocyanidins in comparable amounts. However, only the high molecular fraction form red maple bark extract seemed to contain substantial amounts of high-molecular-weight gallotannins. Supplementary analyses would be required to confirm this result. To conclude, this thesis provides solid information to promote the extraction of red and sugar maple bark at a commercial level. This work offers valuable findings and insights about extract production for application in foods, cosmetics or pharmaceutics. The results obtained help enhance the knowledge about maple bark phytochemicals. Yet, further studies would be required before creating a sustainable biorefinery project based on maple bark. Such investigations, including in vivo toxicity, activity testing, as well as studies about food enrichment using maple extracts are planned for the continuation of this research.
Kouzayha, Abir. "Développement des méthodes analytiques pour la détection et la quantification de traces des HAP et de pesticides dans l'eau : application à l'étude de la qualité des eaux libanaises." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14414/document.
Повний текст джерелаWater pollution presents a very critical problem facing industrial and developping countries. The environmental monitoring of the contaminants seems necessary to understand their sources and impacts. Among a wide variety of organic pollutants present in water,polycyclic aromatic hydrocarbons (PAHs) and pesticides are of particular importance as widespread, persistent, and toxic contaminants. They are usually present at trace levels in theacquatic surfaces; therefore their detection and control require selective and sensitiveanalytical procedures. The Solid-Phase Extraction (SPE) followed by the Gas-Chromatography coupled to Mass Spectrometry (GC-MS) are the most commonly usedtechniques for their analysis in water. Thesis objectives are focused on the development of new analytical methods for the extraction and analysis of these two families of pollutants present in water. To overcone the contraints of the traditional SPE, a new approach was developed consisting on the introduction of the centrifugation in several steps of the procedure. The new method showed practical environmental and economical advantages interms of sample preparation time, simplicity, reduction in solvent use, and cost and isparticularly suitable for routine applications requiring a high sample throughput. Aprogrammed temeperature vaporizing (PTV) injection method was also optimized and validated in order to improve the detection limits for the GC-MS analysis of PAHs. The evaluation of the quality of different water systems in Lebanon including rainwater,groundwater, drinking water and surface water was accomplished in this study
Galand, Nicolas. "Extraction liquide-liquide de cations par des molécules complexantes : Simulations des ligands et des complexes à l'interface entre l'eau et une phase organique ou le CO2 supercritique." Université Louis Pasteur (Strasbourg) (1971-2008), 2007. http://www.theses.fr/2007STR13191.
Повний текст джерелаKuswandi, M. "Procédés de séparation en milieu dispersé : régénération du triéthylène glycol par extraction de l'eau à l'aide d'un brouillard. Etude sur pilote et simulation. Séparation d'hydrocarbures par membranes liquides émulsionnées." Compiègne, 2000. http://www.theses.fr/2000COMP1275.
Повний текст джерелаChu, Thi Thu Huyen. "Biologie cellulaire des aquaporines chez le riz (Oryza sativa L.)." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTG005/document.
Повний текст джерелаAs molecular players involved into the water transport through biological membranes, aquaporins (AQPs) have a role and are regulated in stress response. They were deeply investigated in plants and particularly in rice. Using functional genetic approach, we generated 5 transgenic rice lines based on Nipponbare cultivar, by overexpressing a single AQP in fusion with a fluorescent marker; among them, 3 plasma membrane AQPs (OsPIP1;1, OsPIP2;4, OsPIP2;5) fused with GFP and 2 tonoplast AQPs (OsTIP1;1 and OsTIP2;2) fused with mCherry. Their subcellular localizations in resting condition were investigated. In rice, OsPIP isoforms showed typical homogeneous labelling of the plasma membrane, whereas OsTIP isoforms were observed localized in the tonoplast with a typical labelling of intracellular invaginations that skirted the nucleus. The behaviors of plasma membrane AQPs were tested in salt and drought stress-mimicked-conditions. Abiotic stresses triggered a re-localization of plasma membrane AQPs and salt stress enhanced endocytosis process of OsPIP2;5 in rice root cells. Overexpressing such transgenes did not seem to affect the plant morphology and showed no beneficial effects for grain yield in both non-stress and stress conditions. We took more focus on the contribution of AQPs in rice root water transport in link with root morphology. AQPs contributed a relative high percentage of water transport in whole root system (44-58%) and seemed to contribute more in primary roots rather than in lateral roots
Nouri, Bahia. "Dosage des pesticides dans l'eau : mise au point et application des méthodes de dosage par extraction liquide-solide et analyse par chromatographie en phase liquide et en phase gazeuse." Montpellier 1, 1997. http://www.theses.fr/1997MON13501.
Повний текст джерелаKarpe, Patrick. "Contribution à l'amélioration des limites de détection des micro-polluants présents dans les eaux par utilisation d'une colonne pulsée d'extraction liquide-liquide : application aux dosages chromatographiques des pesticides organo-chlorés." Montpellier 2, 1987. http://www.theses.fr/1987MON20247.
Повний текст джерелаKouzayha, Abir. "Développement des méthodes analytiques pour la détection et la quantification de traces des HAP et de pesticides dans l'eau. Application à l'évaluation de la qualité des eaux libanaises." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2011. http://tel.archives-ouvertes.fr/tel-00786974.
Повний текст джерелаBannerman, William Karikari. "Spéciation et distribution du mercure et de l'arsenic dans le bassin de la rivière Ankobra (Ghana) : Impact des mines d'or." Pau, 2003. http://www.theses.fr/2003PAUU3007.
Повний текст джерелаGold has been mined in the Ankobra river basin of Ghana for centuries. These activities emit mercury and arsenic whose impacts could be deleterious to the basin's ecosystem and the human population. To assess these impacts, mercury and arsenic were analysed in water, bed and suspended sediments, soils, edible vegetables and fish collected from the basin. Tota concentration and speciation analysis were done by single and hyphenated techniques of chromatography and atomic fluorescence spectrometry. High levels of mercury and arsenic were found in the proximities of the mining zones. The two elements are transported mainly in the aqueous phase of the river and they showed seasonal variation in both water and sediments. Detectable methylmercury in sediment averaged 1% of the total. Arsenic species detected in water and sediments were the inorganic forms. The sediments and fish were significantly contaminated in mercury
Champeyroux, Chloé. "Caractérisation fonctionnelle de protéines en interaction avec l'aquaporine PIP2;1." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT120.
Повний текст джерелаThe root hydraulic conductivity (Lpr) reflects the water transport capacity of the root. During its transfer from the soil to the xylem, water can diffuse in the apoplasm or through the cells (cell-to-cell pathway). At the endodermis, the apoplastic diffusion of water is blocked by the Casparian Strip and suberin lamellae. The cell-to-cell pathway mainly relies on aquaporin activity which can be regulated by protein interactions. This study aims at characterizing new interactants of the root aquaporin PIP2;1: the receptor kinase RKL1 and 4 proteins of unknown function belonging to the Casparian Strip membrane domain Protein Like 1 sub-family (CASPL1-B1/B2/D1/D2). RKL1 is expressed in the endodermis, can physically interact with PIP2;1 and stimulates its water transport function in vitro. However a loss-of-function of RKL1 does not affect the Lpr., independently of a putative functional redundancy with its closest homolog RLK902. Concerning CASPL, D1 is expressed in every tissue of the root whereas B1, B2 and D2 appear to be specifically expressed in suberized tissues. This suggests a putative role of these isoforms in aquaporin regulation and suberisation. At the molecular level, D2 does not modulate PIP2;1 water transport activity despite a physical interaction between the two partners. By contrast, B1 interacts with PIP2;1 preferentially in its phosphorylated form and enhances the water transport activity of the aquaporin. At the plant level, disrupting one or two CASPL genes neither impact the Lpr nor affect the suberisation. However, the loss of function of both PIP2;1 and PIP2;2 reveals a negative effect of these aquaporins on suberisation. In conclusion, this study, uncovered novel regulation mechanisms of aquaporins. It also raises the question of the existence of a putative relationship between water transport by the apoplastic pathway and by aquaporins
AlHaddad, Nancy. "Synthèse de nouvelles entités complexantes à base de calix[4]pyrrole pour la décontamination des milieux aquatiques en radionucléides naturels." Thesis, Littoral, 2020. https://documents.univ-littoral.fr/access/content/group/50b76a52-4e4b-4ade-a198-f84bc4e1bc3c/BULCO/Th%C3%A8ses/Toxicologie/Version_finale_These_Nancy_AlHaddad.pdf.
Повний текст джерелаRadionuclides are found naturally in air, soil and water and generate radioactivity in the environment. As a result of recent anthropogenic activities such as uranium mining or the production of oil and natural gaz, larger quantities of natural radionucleides have been released and induce a risk to Human Health. One of the most important routes for Human contamination with radionucleides, other than inhalation, is water contamination that results from the high hydro-solubility of certain radionuclide salts. In fact, maximum contaminant levels for radionuclides contamination, especially in public water supplies, have been internationally regulated. In order to comply with these requirements, methods for decontaminating water from radionuclides have been developes, among which macrocyclic extractants such as calixpyrroles. With a preorganized cyclic structure, these macrocycles exhibit chelating properties that are also found in their phenoxycalix[4]pyrrole (PCP) homologs. However, the latter has an increased potential for chemical functionalization allowing the introduction of additional chelation sites due to the presence of four phenolic entities. In this context, the synthesis of PCP derivatives and the study of their ability to complex and extract stable or radioactive elements have been studied. For this, the functionalization of the PCP was carried out by functional groups such as : carboxylic acid, hydroxamic acid, azide, amine and heteroaryl-extended derivatives. At the end of these syntheses, the study of the chelation capacities of the derivative 2-pyridino-1,2,3-triazolo-PCP was carried out and the existence of a selective complexation of ferrous and ferric iron in DMSO was demonstrated by molecular fluorescence. As for the chelation capacities for halides, they were studied by ¹H NMR and molecular fluorescence titrations and showed a selectivity for fluoride. A second part of this work was devoted to the synthesis and study of the properties of a new polymerof PCP crosslinked by epichlorohydrin (PCP-EP), in the aim of engaging it into solid/liquid extractions, applied for the decontamination of aqueous effluents containing radionuclides. In this series of polymers, PCP-EP is the first to be reported in literature. Accordingly, its structure was determined by NMR, FTIR and TGA, then its chelation capacities towards halides was tested by ion chromatography after solid/liquid extractions. The results demonstrated that this polymer, unlike its monomeric structure, has a higher affinity for iodide. The solid/liquid extraction capacities of radionuclides by PCP-EP were then studied by a gamma spectrometer coupled to a High Purity Germanium detector, using aqueous solutions containing radionuclides and resulted in an extraction rate of 22% for Ra-226. The development of a Doehlert experimental design was then carried out in order to optimize the experimental extraction conditions. During this step, the study of BA²⁺, a stable metal with a chemical behavior similar to RA²⁺, was prioritized in order to reduce the production of radioactive waste. The results of this experimental design led to optimal extraction conditions of pH, temperature and time, which translated to an aqueous radionuclides-containing solution, showed the ability of PCP-EP to extract 89% Ra-226
Brogat, Marine. "Développement d'une méthode d'extraction sur multiples phases solides (MSP2E) de micropolluants organiques." Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S003/document.
Повний текст джерелаIn case of accidental or intentional pollution in aquatic environments, plans are implemented to use any and all recourses and tools available in order to evaluate and to characterize pollution. The current method involves a sampling on site followed by laboratory analysis. But, in case of significant pollution, a rapid decision is clearly needed. The thesis project arises in this context and has been the development of a rapid on-site analyzer for the detection of organic micropollutants in water especially in the context of accidental pollution. The aims of this project were to develop a method (MSP2E) of pre-concentration and fractionation of multiple solid phases followed by a elution step and UV detection. Eluting fractions are related to physico-chemical properties of the target compounds. A predictive approach has been established to determine a priori the fraction in which the molecules are eluted. The UV spectrum analysis may identify the molecule in the different fractions. A database was performed to identify the different characteristics (physico-chemical, eluting fraction, UV spectrum) and for the recognition of a molecule. As part of this work, a hundred molecules were studied alone or in mixture. Finally, the methodology has also been transposed to another application for the determination of doping in urine
Ben, Sghaier Rafika. "Perturbateurs endocriniens dans le milieu aquatique : développement analytique et faisabilité de traitement." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10126/document.
Повний текст джерелаThe occurrence of endocrine-disrupting compounds in the aquatic environment has brought increasing concern due to their potential adverse impacts on ecosystems and humans. These compounds are generally present in complex water matrices, such as surface waters at trace levels (ng/L) making their analysis difficult. In this work, an analytical method for the simultaneous determination of 13 endocrine disrupting chemicals (EDCs), including 5 steroid estrogens, 1 progestogen, 1 androgen and 6 endocrine-disrupting phenols in water was developed using solid phase extraction (SPE), derivatization and gas chromatography-mass spectrometry (GC-MS).The method was validated by spiking the 13 EDCs to the interest matrix. The limits of quantification were 1 ng/L and 5-50 ng/L for phenolic compounds and hormones respectively. The validated method was applied to assess the contamination level of the targeted EDCs in many sites in Northern France and in Tunisia. The majority of the considered compounds were detected in the different sampling sites. The last part of this work is the feasibility study for the elimination of PE by adsorption techniques on modified brick residues and bio-remediation by blue-green algae (SPIRULINA)
Ruiz, Arredondo José Vicente. "Analysis and evaluation of economic policy instruments for environmental control in Mexico." Thesis, Paris 1, 2016. http://www.theses.fr/2016PA01E021/document.
Повний текст джерелаThe sustainability or water resources in Mexico is challenged, among other things, by inadequate regulation tools, limited enforcement capacity, and the uncertainty related to climate change. This thesis analyses key aspects of these challenges with the overall objective of contributing to the economic literature and providing inputs for evidence based policy making. The thesis is composed of three chapters. The first chapter looks at the mechanisms regulating groundwater extraction. In particular, it analyses the distortion caused by electricity subsidies and their effects on groundwater overdraft. It contributes to the existing literature by providing estimates on cross-price elasticities related to irrigation water demand in Mexico. The results of this chapter show that changes in the price of ground water not only affect the amount of water pumped, but also the allocation of labour and fertilizers. The second chapter studies the effects of environmental inspections on illegal water extraction across Mexican municipalities. Results show that the main inspection program led by Mexico's water agency does have an impact on the number of irrigators extracting water without a valid concession. However, further efforts improving the capacity of regional offices are required for this program to have a substantive effect on water sustainability. Finally, the third chapter addresses some of the concerns related to climate change by analyzing the effects of droughts and floods on internal migration trends in Mexico. Results show that both droughts and floods act as push factors for internal migration. In addition, results also show that income differential, murders, and educational attainments are key drivers for internal migration in the country
El, Azzi Désirée. "Transfert de polluants organiques et inorganiques dans les hydrosystèmes en période de crue : interactions avec les matières en suspension et la matière organique." Toulouse 3, 2012. http://thesesups.ups-tlse.fr/1885/.
Повний текст джерелаThe mechanisms involved in the transfer of organic and inorganic pollutants to streams in agricultural watersheds are largely studied. However, few studies concern storm events responsible for the transportation of large quantities of pollutants to the outlet and they rarely take into account a multi-pollution dynamic. A heavy monitoring was therefore conducted during the storm event of May 2010 at the outlet of the Save river (1110 Km2) in the south west of France. The majority of pollutants and their controlling factors (dissolved and particulate organic carbon (DOC and POC) and suspended particulate matter (SPM)) are more concentrated during storm flow than base flow and their concentration increases with stream water discharge. Pollutants are also more concentrated during these events. Hydrograph separations showed that pollutants are primarily transported in the surface runoff adsorbed onto SPM when they have a low solubility (hydrophobic) and in the subsurface runoff linked to DOC when they are soluble. Different kinds of chemical bonds can exist between pollutants and the different SPM fractions (organic matter, clay and oxides). In order to investigate these bonds, we studied in particular Cu dynamic in the small wine growing catchment of Baillaury (18. 2 Km2), close to Banyuls sur Mer (Eastern Pyrénées), within the framework of the CRUMED project (EC2CO-INSU/CNRS). This Mediterranean type-flow regime stream is mostly cultivated with vineyards and has been treated with Bordeaux mixture for centuries. Moderate to significant enrichments of soils at different depth, river bottom sediments and suspended matters were revealed. Anthropogenic contribution to this enrichment is estimated between 50 and 85 % in all samples showing that the Cu present in the river is mainly due to agricultural practices. Sequential chemical extractions SCE) allow us to determine Cu distribution in the different residual and non-residual fractions (exchangeable, acido-soluble, Mn and Fe oxides, organic matter), showing that anthropogenic Cu is mainly adsorbed onto iron oxides. The isotopic Cu composition measured in each fraction shows that Cu transported in solution and adsorbed onto organic matter seems to be associated without any fractioning. Gross samples have signatures similar to the bedrock and so studying the detailed SCE fractions is essential. Combining SCE and isotopic signatures is a powerful tool to understand Cu distribution and transfer in the environment. However, in the environment, a pollutant is rarely alone and other pollutants can influence its fate. Therefore, in order to investigate the influence of the presence of other pollutants on a pollutant's adsorption, organic (two pesticides: alachlore and aclonifen) and inorganic (two heavy metals: Cu and Cd) pollutants adsorption on natural SPM (collected in the Save river during the flood) were studied. Most studied pollutants were influenced by the presence of one or more other pollutants in the water, trace metals to a lesser extent than pesticides. The order of presence in the water also influences the adsorption rate of the pollutant onto SPM. The mutual influence can be due to competition for the same adsorption sites or to the creation of complexes between pollutants. These complexes can modify the adsorption capacities of each pollutant. These original results obtained in this work open up new perspectives and requests
Said, Ahmed Hami. "Etude de l’alimentation hydrique du palmier dattier (Phoenix dactylifera L.) dans le contexte pédoclimatique de la zone littorale de la République de Djibouti." Thesis, Orléans, 2015. http://www.theses.fr/2015ORLE2034/document.
Повний текст джерелаDate palm is one of the few food crops adapted to the extreme weather conditions (drought, salinity), such as encountered in Djibouti. In the context of highly limited water resources, knowledge of the date palm water requirements is essential. The objective of this research was to determine the date palm water requirements, in the Djibouti pedoclimatic context, using in situ monitoring of water transport in the soil-plantatmosphere system, at the scale of a single date palm tree, and to quantify the date palm root water uptake. A fully developed date palm tree was instrumented at the irrigation basin scale, using several access tubes for neutron probe for monitoring the soil volumetric water content, and several tensiometers, installed from 10 to 160 cm depth. Three infiltration/redistribution experiments have been performed successively, the first without alteration of the soil-plant system, the second after cutting off a date palm tree while allowing the surface evaporation, the last with covering the soil surface to avoid evaporation. The results show large heterogeneity in soil hydraulic properties, with stratification linked to the coastline sedimentary context. The root water uptake is observed up to 80 cm depth. The date palm water requirements in the fresh period are estimated at 130 liters per day with a frequency of irrigation of one time every two weeks. For the first time, the date palm cultural coefficient has been established in the Djibouti climatic conditions (kc = 1.39). The obtained results will contribute to better management of irrigation and to improve the control of soil salinization in the pedoclimatic context of the Republic of Djibouti
Tlili, Inès. "Développement analytique et suivi dans l’environnement des traces des antibiotiques à usage humain et vétérinaire." Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10208.
Повний текст джерелаDue to their widespread use in human and animal health care, antibiotics and other drug residues are ubiquitous in the environment in general and the aquatic environment in particular. Given their potential impacts on the functioning of the ecosystem and public health, the quantification of drug residues on the environment has become a necessity. Various assay techniques have been found to be suitable for the reliable detection of such compounds. However, quantification can be difficult because these emerging contaminants are present in the trace or ultra-trace state. Therefore, the accuracy of environmental analyzes depends on both the effectiveness and the robustness of the extraction and quantification method. Trace analysis procedures for these emerging contaminants were therefore developed and methods based on LC-MS / MS analyzes were also developed. For aqueous samples, extraction is carried out on solid phase (SPE, OASIS HLB). MLOQs range from 0.2 to 3 ng / L. For the solid matrix, the extraction procedure at high temperature and pressure was used followed by SPE purification. To assess the context of total pollution, the validated analytical methodology was applied to drinking and wastewater samples from France and Tunisia. Drug residues associated with suspended solid matter (SSM) were also quantified to complete the assessment of the degree of environmental pollution