Dissertations / Theses on the topic 'Legs nitraté'
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Erostate, Mélanie. "Dynamique spatio-temporelle des flux naturels et anthropiques vers les hydrosystèmes littoraux tributaires des eaux souterraines : Investigations isotopiques et géochimiques pour la compréhension des interactions aquifères-lagune sur le site de Biguglia (Haute-Corse)." Thesis, Corte, 2020. http://hal-univ-corse.archives-ouvertes.fr/view_by_stamp.php?&action_todo=view&id.
The exacerbated anthropization of coastal hydrosystems poses a significant threat to groundwater and ecosystems that depend on it, then called "groundwater-dependent ecosystems". Like the Biguglia hydrosystem (Corsica, France), rapid and disorganized urbanization, as well as industrial and agricultural activities developed on the Marana plain are major sources of groundwater degradation. This strategic resource, used for the drinking water supply of the Bastia urban area, presents the markers of multiple and diffuse contaminations. In addition to being problematic for human water needs, the groundwater qualitative degradation of the Marana aquifer also constitutes a threat to the fragile ecosystem of the Biguglia lagoon and the sustainability of the ecosystem services it provides. In this context of increasing pressures, a strong knowledge of the Biguglia hydrosystem behavior is essential to ensure sustainable management of water resources. To this end, a multi-tracer geochemical and isotopic approach has been developed in order to better constrain the state of the groundwater resource, the hydrodynamic conditions and the nature of aquifer-river-lagoon interactions. The study of the stable isotopes of the water molecule (18O, 2H) has highlighted the recharge complexity. The Marana aquifer benefits from an indigenous recharge through direct infiltration of precipitation on the plain and an allochthonous recharge through precipitation from the schistous reliefs. The infiltration of river water from the Bevincu and Golu rivers and the lateral contribution of water from the schistous reliefs also contribute to the aquifer recharge. The developed mixing model (18O, Cl- and HCO3-) allowed a semi-quantitative estimation of the mixing processes. It demonstrates the complex aquifer behavior, with a significant difference in the contribution of schistous groundwater depending on the location and depth of the resource. It is also clear that the Biguglia lagoon is partially dependent on groundwater. The Marana plain is subject to qualitative degradation due to the excessive presence of nitrates (NO3-) and organic micropollutants. According to the NO3- (15N-NO3-, 18O-NO3-) and Boron (11B) isotopes, the main sources of nitrogen are soil and wastewater. The correlation between NO3- concentrations and water residence time (3H and CFCs) highlighted the storage and the groundwater archiving capacity. With regard to the evolution of land use, the progressive modification of the nitrogen sources recorded in the aquifer made it possible to trace the socio-environmental trajectory of the Biguglia hydrosystem. The contemporary degraded state of the resource mainly results from the pollution legacy linked to historical human activities. The conceptual model developed provides new elements that can help towards the implementation of relevant management strategies, to ensure the sustainability of water resources and associated ecosystem services
Weiss, Nathalie. "La pollution des eaux par les nitrates : cas particulier de la région charentaise." Bordeaux 2, 1994. http://www.theses.fr/1994BOR2P017.
Machado, Franck. "Reactions photochimiques induites sur les composes phenoliques par excitation des ions nitrate et nitrite en solution aqueuse." Clermont-Ferrand 2, 1994. http://www.theses.fr/1994CLF21610.
Pham, Hoai Nam. "Estimation de nitrate, nitrite et autres composés à partir de spectres ultraviolets, pour l'agroalimentaire et les eaux résiduaires." Compiègne, 2008. http://www.theses.fr/2008COMP1762.
Contents of nitrate, nitrite and some others ions can be estimated by UV spectrophotometry in wastewater also in vegetables for processing control as well as for in-situ monitoring. The method is based on the spectral identification: UV spectrum of a sample is considered as a linear combination of absorption spectra, named reference spectra. Mathematical identification of UV spectra can discriminate nitrite from nitrate, in the range of 0. 5 to 5 mg-N/L, even in presence of up to 100 mg/L chloride and up to 200 mg/L bicarbonate. The tests in different real conditions show that this method can be used for on-line monitoring in the Wastewater Treatment Plant of Paris. Several fresh vegetables as well as frozen spinaches have been tested. The nitrate content varied from 377 to 3240 mg/kg of fresh vegetables, and 545 to 1190 mg/kg of frozen spinach. The recovery of added nitrate ranged from 91 to 99%. The validation tests carried out in one industry showed the potentiality of the method of spectral identification. This method does not require almost any consumable, is quantitative and very fast reading with easy and low maintenance. The UV-Pro software identification used during this thesis has always shown similar results to those obtained by PLS or PCR, it is based on considerations and methods similar resolution. The prospects of this work will be the use of non-linear methods of identification and the use of complementary methods to expand the potential of UV spectrophotometry
Soropogui, Koïkoï. "Mise au point de capteurs économiques pour la détermination électroanalytique des ions nitrate ou nitrite dans les eaux naturelles." Lyon 1, 2007. http://www.theses.fr/2007LYO10268.
Lefebvre, Hervé. "Etudes thermodynamique et cinétique de la corrosion du fer par les mélanges de nitrate et de nitrite de sodium fondus." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37615108t.
Lefebvre, Hervé. "Etudes thermodynamique et cinetique de la corrosion du fer par les melanges de nitrate et de nitrite de sodium fondus." Paris 6, 1988. http://www.theses.fr/1988PA066353.
Bourgeois, Ilann. "Dépôt des nitrates atmosphériques sur les prairies subalpines du Lautaret." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAV059/document.
Increasing rates of atmospheric nitrate (NO3-atm) deposition in nutrients poor mountainous regions have led to critical changes in nitrogen (N) availability, with consequences on biodiversity (plants, microbes), soils N turnover, and water nutrients status. This will ultimately affect human populations through the loss of critical ecosystem services (e.g., provision of clean freshwater, erosion control, biodiversity). If the impacts of NO3-atm deposition to N-limited basins are now well documented, little is known about the processes driving NO3-atm retention in subalpine ecosystems. In this context, new tools are necessary to better understand the fate of NO3-atm in mountains and to predict the mid and long-term ecological consequences of increasing NO3-atm deposition. This work uses a high-resolution multi-isotopic technique combining 17O, 18O and 15N signatures of NO3- in the different subalpine compartments to understand the temporal and spatial evolution of NO3-atm partitioning in a subalpine watershed of the French Alps. Subalpine streams elevated year-round exports of NO3-atm suggest that the watersheds are kinetically N saturated, especially after snowmelt. The isotopic composition of NO3- in freshwaters also points at the rapid processing of snow ammonium, confirming that snowmelt is “hot moment” for the N cycle in seasonally snow-covered catchments. The monitoring of soils reveals varying NO3-atm proportions depending on the land management treatments and implied biotic and abiotic characteristics. Two dominant subalpine plants showed high proportions of NO3-atm in organs acquired by both root and foliar uptake. These scientific breakthroughs will ultimately lead to a better understanding of how NO3-atm deposition affects the environment
Wirth, Judith. "La régulation des transporteurs de nitrate au niveau ARN et protéines dans les racines de Arabidopsis thaliana." Montpellier, ENSA, 2006. http://www.theses.fr/2006ENSA0015.
BENVENUTI, PASCAL. "Problemes lies a l'evolution des teneurs en nitrates dans les eaux souterraines." Strasbourg 1, 1989. http://www.theses.fr/1989STR15009.
Mattei, Coraline. "Réactivité hétérogène de pesticides adsorbés sur des particules atmosphériques : influence des paramètres environnementaux sur les cinétiques." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0181.
Environmental contamination by pesticides is ubiquitous and induces health and environmental impacts. Once applied, some of the pesticides reach the atmosphere, where they distribute between the aqueous, gaseous and particle phases. Most of the currently used pesticides are semi-volatiles and are therefore partially adsorbed on the atmospheric particle surfaces and undergo heterogeneous degradation reactions. If their reactivity in the gaseous phase is often known, their reactivity in the particle phase remains poorly described. This experimental work allowed studying the influence of environmental parameters (relative humidity, type of particles, pesticides surface concentration) on the reactivity of eight pesticides (cyprodinil, deltamethrin, difenoconazole, fipronil, oxadiazon, pendimethalin, permethrin, tetraconazole). They were adsorbed on mineral surfaces mimicking mineral aerosol particles (hydrophobic and hydrophilic silica, Arizona sand) to simulate atmospheric degradation by the mains atmospheric oxidants (ozone, hydroxyl radicals (OH) and nitrate radicals (NO3)). Results showed that relative humidity, particle type, and pesticide concentration can influence the heterogeneous degradation of pesticides with ozone and OH radicals. They also showed the efficiency of NO3 radicals for the atmospheric heterogeneous degradation of pesticides (half-lives in the particle phase from 2 to 16 d with NO3 compared to 0.4 to > 800 d with ozone and to 3 to > 100 d with OH). Results obtained allow a better understanding of the atmospheric fate of pesticides and will contribute to predict of atmospheric contamination
Fazzolari, Correa Elisa. "La réduction dissimilative du nitrate en ammonium dans les sols." Lyon 1, 1989. http://www.theses.fr/1989LYO10056.
Flipo, Nicolas. "Modélisation intégrée des transferts d'azote dans les aquifères et les rivières : application au bassin du grand morin." Phd thesis, École Nationale Supérieure des Mines de Paris, 2005. http://pastel.archives-ouvertes.fr/pastel-00001432.
Alboresi, Alessandro. "Etude physiologique et génétique du signal nitrate chez Arabidopsis thaliana." Versailles-St Quentin en Yvelines, 2005. http://www.theses.fr/2005VERS0029.
This aim of my PhD thesis was the study of nitrate (NO3-) signalling in Arabidopsis through two different approaches : Screening of mutants overexpressing nitrite reductase gene (NII) by the use of luciferase reporter gene LUC. Within the population of mutants overexpressing luciferase, only one is also overexpressing the endogenous gene. We have started the characterization of the mutant which seems to be affected either in nitrate signal transduction or to be a new cnx mutant. Nitrate relieving seed dormancy. We have shown that nitrate breaks dormancy both whether it is present in the germination media or given to mother plants. The transcriptomic analyses we performed show that NO3- interact with GA and ABA pathways and could represent a good tool for future candidate gene approaches
Martin, Charlotte. "Mécanismes hydrologiques et hydrochimiques impliqués dans les variations saisonnières des teneurs en nitrate dans les bassins versants agricoles : approche expérimentale et modélisation /." Rennes : Géosciences-Rennes, 2003. http://catalogue.bnf.fr/ark:/12148/cb39137839b.
Curie, Florence. "Rétention de nitrate dans les zones humides riveraines : rôle des facteurs hydrologiques, géomorphologiques et biogéochimiques : approche multi-échelle dans le bassin de la Seine." Paris 6, 2007. http://www.theses.fr/2006PA066353.
Pulou, Jérémy. "Les anciennes cressonnières de l'Essonne : Effets de la recolonisation des zones humides artificielles sur la dynamique de l'azote." Phd thesis, AgroParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00910075.
Deyine, Abdallah. "Annelation via une addition de type Michael catalysée par les acides de Lewis avec les éthers d'énols silylés azotés : application à la synthèse d'alcaloï͏̈des." Rouen, 1993. http://www.theses.fr/1993ROUES008.
Briand, Cyrielle. "Approche multi-traceurs pour la détermination de l'origine des nitrates dans les eaux souterraines : exemple d'une source karstique dans les Landes." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2014. http://tel.archives-ouvertes.fr/tel-01064359.
Muller, Bertrand. "Regulation de l'absorption racinaire de nitrate par les produits de son assimilation foliaire." Montpellier, ENSA, 1992. http://www.theses.fr/1992ENSA0003.
Xue, Chaoyang. "Les sources de HONO atmosphérique rural et leur impact sur la qualité de l'air régional dans la Plaine de Chine du Nord." Thesis, Orléans, 2020. http://www.theses.fr/2020ORLE3107.
Air pollution is still an environmental problem that urgently needs to be solved in the North China Plain (NCP). With the aim to explore nitrous acid (HONO) formation and its impact on regional air quality in the NCP, the development and systematic assessment of instruments to measure atmospheric HONO concentration and soil HONO emission flux were realized. Based on field measurements, a 3D chemistry-transport model (the Community Multiscale Air Quality Modeling System, CMAQ) and a box (0D) model (Master Chemical Mechanism, MCM) were used to explore the HONO budget and its impact on regional air pollution, e.g., summer ozone (O3) pollution and winter haze pollution. We found that agricultural soil was an important HONO source with a significant impact on regional O3 pollution in the summertime. A new soil HONO emission mechanism related to nitrification was proposed. HONO also plays an important role in atmospheric oxidizing capacity and deteriorating regional air quality in the wintertime
Benhamou, Cyril. "Modélisation de l’effet des interactions haies-cultures sur les transferts d’eau et d’azote à l’échelle d’un petit bassin versant agricole." Rennes, Agrocampus Ouest, 2012. http://www.theses.fr/2012NSARD064.
One negative effect of agricultural intensification for more than fifty years has been water pollution by nitrates, which has environmental and economic consequences. In this context, the agro-ecosystem must develop into innovative systems through a combination of use and preservation of natural resources. Buffers zones, such as hedgerow networks, could be a tool to partially regulate nitrogen flow at the watershed outlet. In Britany (western France), where nearly 60% of hedgerows disappeared from 1960-1980, the issue is particularly important. The problem dealt with here is to quantify, at the watershed scale, the impact of these buffer zones to maximize their value with management-landscape strategies. The assumption is that the hedgerow impact varies depending on its position on the hillslope. Compared to previous studies, the originality of this work has been to focus on hedgerow position in the landscape and therefore its relations with groundwater, associated crops or pastures, as well as the influence of pruning. This work is divided into two parts. The first was to assess the impact of the hedgerow on local variations in soil moisture and hydrological functioning of a hillslope depending on hedgerow position. An experimental site was instrumented in the north of the Ille-et-Vilaine department (Brittany) and monitored for a year (September 2009-September 2010). The second part was to develop a new submodel for hedgerows in the spatially explicit model TNT2. We developed the concept of double-cover cell, which takes into account impact of interactions with crops and pruning. Experimental results showed that hedgerow can be distinguished from other vegetation by its water uptake in deeper soil layers, and that this uptake is affected by management (pruning) of the hedgerow. Close to the hedgerow, when the water table is deep, capillary rise contributes to soil water variations. Local reduction in soil water content and rainfall interception by the hedgerow canopy seems to have an influence on groundwater flow in autumn. The hedgerow submodel was thoroughly tested, and its behavior generally met expectations. The processes identified as important in field studies and the literature review were broadly represented, and their variations due to climatic and topographic conditions were consistent. Model predictions indicated that hedgerow impact on water and nitrogen balances depends on its position in the watershed and the crop associated with it. Competition between the hedgerow and the associated crop increased as water table depth increased, as a function of hedgerow location in the watershed. This competition was partially mitigated by pruning. In contrast, hedgerow presence tended to increase water table depth and soil water deficit, which reduced denitrification and mineralization. Simulations of the-Kervidy Naizin watershed predicted that presence of a hedgerow network reduces annual water and nitrogen flow at the outlet. At shorter time scales, the effect of hedgerows is more pronounced in spring and autumn, when discharge is low
Sall, Kéba. "Influence du déficit hydrique sur les activités nitrate réductase et nitrogénase chez le soja." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37609667g.
DUVIVIER, STEPHANE. "Reactivite en solution et aux interfaces dans les liquides ioniques eau - nitrate d'ethylammonium fondu." Paris 6, 2000. http://www.theses.fr/2000PA066564.
DELHON, PATRICIA. "Regulation de l'absorption racinaire du nitrate par les parties aeriennes : effet de la lumiere." Montpellier, ENSA, 1993. http://www.theses.fr/1993ENSA0022.
Kouassi, Anne Patricia. "Recherche d'alternatives aux nitrates et nitrites dans les produits carnés." Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26787.
The aim of this study was to develop formulations that can replace nitrates and nitrites in meat-based products while keeping the same shelf life as nitrites and also, their organoleptic, antimicrobial and antioxydant properties. A qualitative and quantitative screening of spices have been made and three spices were selected, cloves, cumin and cinnamon. Different fruit powders were tested to get closer to the pinkish color which nitrites give to meats. Then, an organoleptic tests were performed on a panel of tasters and the results have helped identify the sweetness of the variety of fruit powder and very interesting sensory properties of several formulations in relation to the addition of nitrites. Finally, a techno-economic analysis was performed and showed a small increase in cost of production of meat products using spices and fruit powder, due to a slight increase in the cost of raw materials.
Martin, Charlotte. "Mécanismes hydrologiques et hydrochimiques impliqués dans les variations saisonnières des teneurs en nitrate dans les bassins versants agricoles." Rennes 1, 2003. https://tel.archives-ouvertes.fr/tel-00003939v2.
Arlot, Marie-Pierre. "Nitrates dans les eaux : Drainage acteur, drainage témoin ? Les enseignements d'une approche hydrologique et hydraulique sur (1) l'influence du drainage agricole sur la contamination diffuse des eaux par les nitrates et (2) sur les possibilités d'utiliser les parcelles drainées pour l'analyse de la dite contamination." Paris 6, 1999. http://www.theses.fr/1999PA066018.
Taochy, Christelle. "Transport membranaire de NO3 sous contrainte saline : rôle de NAXT2 dans la translocation du NO3 vers les feuilles et le contrôle du fonctionement stomatique chez A. thaliana." Thesis, Montpellier, SupAgro, 2012. http://www.theses.fr/2012NSAM0024/document.
NO3– secretion systems at the plasma membrane of plant cells play an important role in stomata activity and plant response to biotic and abiotic stresses. Despite of few recent advances, these systems are still poorly known at the molecular level. During my thesis, I worked on the characterization of the physiological role of NAXT2, a member of the NAXT (NitrAte eXcretion Transporter) sub-group from the large NRT1/PTR transporters family in Arabidopsis thaliana. The results presented here show that NAXT2 is a NO3– transporter and that it is mainly expressed in root pericycle cells, close to the xylem vessels. Under salinity constraint and relatively to wild type plants (WT), a NAXT2 knock-out mutant (naxt2-1) displayed a defect in NO3– distribution towards the shoots and in NO3– secretion into the xylem sap, which lead to a decrease in shoot NO3– content. Thus, NAXT2 is involved in NO3– xylem loading under salinity constraint. None of the phenotypic differences described in this work between WT and mutant was observed under osmotic stress or standard culture conditions, suggesting that NAXT2 is specifically involved in response to the ionic component of salt stress. Finally, after a prolonged salt treatment, naxt2-1 shoot biomass was lower than that of WT, indicating that NAXT2 plays an important role in plant adaptation to mild salinity constraint. Altogether, this work suggests that NAXT2 is involved in a major physiological function, the NO3– translocation, control point of nitrate distribution and in plant adaptation to salinity constraint
Boisson, Jean. "Sur l'interaction eau/anion : les caractères structurants et déstructurants, la rupture de symétrie du nitrate." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2008. http://tel.archives-ouvertes.fr/tel-00363808.
Prat, Bofill Fortià. "Estudi dels nitrats a l'aigua de les fonts d'Osona. Un repte per l'agricultura i per l'educació." Doctoral thesis, Universitat de Vic - Universitat Central de Catalunya, 2022. http://hdl.handle.net/10803/673518.
The thesis has focused on the study and monitoring, over 18 years, of nitrate contamination of water sources in the Osona region. Control methods and factors that can influence such as land use, the geographical location and the rainfall are proposed. The particular recharge of aquifers and the different rainfall regime, favorable and more abundant in areas without nitrate pollution, suggest that the recovery of water from springs could be easy if the management of livestock waste and fertilization of crops were correct. On the other hand, it is a contribution to interdisciplinary research between science and education as a result of an important socio-environmental problem that needs an urgent response in order to preserve the natural heritage such as the quality of groundwater of the region. Finally, the thesis makes a contribution to the education of the SDGs related to water quality and education.
Ciències Experimentals i Tecnologies
Jambert, Corinne. "Emissions de composés azotés dans l'atmosphère par les agrosystèmes fertilisés : mai͏̈siculture dans les Landes de Gascogne." Toulouse 3, 1995. http://www.theses.fr/1995TOU30043.
Kalalian, Carmen. "Réactivité atmosphérique des composés organiques volatils oxygénés biogéniques (aldéhydes et alcools insaturés). Etudes cinétiques de la réaction entre les radicaux peroxyles et le radical nitrate." Thesis, Reims, 2018. http://www.theses.fr/2018REIMS023/document.
Biogenic volatile organic compounds (BVOC) account for 90% of VOC emissions in the atmosphere. These VOCs can be removed from the atmosphere by reaction with photo-oxidants (OH, NO3, Cl and O3) as well as by photolysis. All these processes are governed by a chain mechanism whose carriers are mainly free radicals such as peroxy radicals RO2. Hence the importance of characterizing the reactivity of these species that play a key role in the atmospheric degradation of VOCs. In this context, this thesis focuses on the determination of the temperature dependent kinetic data as well as the mechanism of the ozonolysis reaction and the UV absorption spectra along the photolysis of six unsaturated oxygenated VOCs (trans- 2-pentenal, trans-2-hexenal, 2-methyl-2-pentenal, 1-penten-3-ol, cis-2-penten-1-ol and trans-3-hexen-1-ol). Likewise, the temperature dependent kinetic parameters of the reaction of three peroxy radicals (CH3OCH2O2, CH3C(O)CH2O2 et (CH3)2C(OH)CH2O2) with nitrate radicals were also determined. Three experimental setups coupled to treatment methods were used to extract these data: an atmospheric simulation chamber coupled to both a Fourier-transform infrared spectroscopy (FTIR) and a gas chromatography connected to a mass spectrometry (GC/MS), a device for measuring UV-Visible spectra and a laser photolysis coupled with UV-visible spectrometry and laser diode spectroscopy. The kinetic parameters were used to estimate the atmospheric lifetimes of the studied species. While the mechanistic data were used to establish their ozonolysis mechanisms. All the collected data enrich kinetic, mechanistic and spectroscopic databases, improving atmospheric models specially those involving VOCs
El, Jarjaf Abdellah. "Performance d'algues unicellulaires et d'une lentille d'eau dans le traitement d'eaux enrichies en nitrates et en métaux." Rouen, 1995. http://www.theses.fr/1995ROUE05NR.
The purification of mediums containing nitrates and heavy metals (Cd, Cu and Mn) has been realised with three freshwater species : two microalgae (Chlorella vulgaris and Selenastrum capricornutum) and a duckweed Spirodela polyrhiza. The optimal growth conditions for all species are obtained with 150 mg/l of N03- for the microalgae and 200 mg/l for the duckweed. The nitrate toxicity threshold is over 800 mg/I for the three studied species. With low nitrate concentration (21 mg/l), the metals toxicity is very important. For high nitrate concentration, the metals toxicity decreases with time and initial NO3- level. These three metals alter nitrates metabolism by decreasing their absorption and their reduction to nitrites. Cd and Cu clearly inhibit nitrate reductase activity. The IC50 of these two metals, evalued by enzymatic inhibition assay, are very closed with those observed by algal assays. L'he nitrates fixation abilities (F. C. ) fluctuate with time and initial N03- medium. They can reach about 3000 mg N03-/algae gramms after 7 days treatment. The efficiency coefficients (EC) also fluctuate with time, nitrates concentration and especially with nutritif compounds concentration. Chlorella vulgaris and Selenastrum capricornutum comportments are very similar and they show a réal capacity to purifying waters with high nitrates concentrations. Spirodela polyrhiza tolerate higher metals concentrations than the two microalgae and shows a better middle and long term purification
Perron, Hadrien. "Simulation par la théorie de la fonctionnelle de la densité de l’interaction de l’ion uranyle avec les surfaces de TiO2 et de NiFe2O4." Paris 11, 2007. http://www.theses.fr/2007PA112117.
This study, performed within the framework of a collaboration between the IPN in Orsay and EDF, takes place within the problematic of radioactivity control in geological depository or in nuclear power plants. The interaction mechanisms of ions at solid / liquid interfaces are often very complex and thus very hard to characterize. The use of atomic modelling, and more particularly of ab initio type calculations such as the density functional theory, allow to access to surface complexes structural and energetic properties. First, this theoretical approach has been validated on the experimentally uranyl / rutile TiO2 well-known system. The systematic comparisons between experimental data and theoretical results have allowed to demonstrate the ability of this approach to properly describe this complex system. Then, a similar study has been performed as a predictive tool on the uranyl / NiFe2O4 system which is not characterized experimentally. The goal of these studies was to determine if theoretical calculations are able to bring usable and reliable data when the experimental studies are too hard to set up
Mellet, Philippe. "Réactivité du nitrite dans les produits carnés action sur les acides aminés, protéines et lipides." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb375996017.
Soulard, Christophe. "Les agriculteurs et la pollution des eaux par les nitrates : proposition d'une géographie des pratiques." Paris 1, 1999. http://www.theses.fr/1999PA010596.
Environnemental questions lead researchers to study the relations of farmers with their work space. In this thesis, i propose a geography of the practices whose object is the confrontation of perceptions and practices of space by farmers, with the categories of space, milieu and territory, used by other actors to solve a question of pollution. The method of research consist in survey with farmers whose are concerned by a local problem of pollution. First, I study the definition of the "non-polluting" practices recommended to the farmers. The analysis of the local effects of environmental policies in two local areas of burgundy reveals a diversity of interpretations of the question according to the areas, the districts and the farmers. This diversity is explained by the combination of three space components of the local question : the space of perception of agricultural pollution, the space of application of environmental policies and the space of local management of drinking water. Then, I study the adoption of the "non-polluting" practices by the farmers. The study of the practices of adjustment to the field of the nitrogen fertilisation of wheat makes it possible to identify various forms of appreciation of the heterogeneity of the soils, connected to two major geographical facts : the logic of spatial organisation of field operations and the strategies of risk limitation between fields. In conclusion, I propose a grid to read the space components which intervene in the treatment of a problem of pollution. I conclude with a reflection on the issue of renewing the geographical approach to the agricultural activity with the end of understanding and improving the relations between agriculture and environnement
Etique, Marjorie. "Effets de l'activité bactérienne réductrice du fer ferrique et des nitrates sur les transformations des produits de corrosion magnetite et sidérite de l'acier non allié." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0254/document.
Radioactive waste is one of the major problems facing the nuclear industry. To circumvent this issue France plans to store vitrified high-level nuclear waste in a stainless steel container, placed into a non-alloy steel overpack, at a depth of 500m in an argillaceous formation. The main iron corrosion products formed at the surface of the non-alloy steel are siderite (FeIICO3) and magnetite (FeIIFeIII2O4). These compounds are formed in the anoxic conditions present in the nuclear waste repository and play a protective role against corrosion as a passive layer. This work aims to investigate the activity of nitrate-reducing bacteria (NRB, Klebsiella mobilis) and iron-reducing bacteria (IRB, Shewanella putrefaciens) during the transformation of siderite and magnetite, especially those involved in anoxic iron biogeochemical cycle. Klebsiella mobilis and Shewanella putrefaciens were first incubated with siderite or magnetite suspensions (high surface specific area) in order to exacerbate the microbial iron transformation, subsequently incubated with a magnetite/siderite film synthesized by anodic polarization at applied current density. The transformation of siderite and magnetite by direct or indirect microbial processes led to the formation of carbonated green rust (FeII4FeIII2(OH)12CO3). As a transient phase shared by several bacterial reactions involving FeII and FeIII, this compound is the cornerstone of the anoxic iron biogeochemical cycle. The novelty of this thesis is the consideration of bacterial metabolisms of NRB and IRB often overlooked in biocorrosion processes
Bouguerra, Maissa. "Étude de l'élimination des ions nitrate dans les effluents agroalimentaires au moyen d'un adsorbant organosilicate mésoporeux." Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/26966/26966.pdf.
Avazéri, Cécile. "Réduction des oxydes de telliure et de sélénium par les bactéries : rôle de la nitrate réductase." Aix-Marseille 3, 1996. http://www.theses.fr/1996AIX30082.
BONAL, CHRISTINE. "Etude thermodynamique de la complexation des cations lanthanide trivalents par les anions nitrate en solution aqueuse." Clermont-Ferrand 2, 1997. http://www.theses.fr/1997CLF21913.
Colobert, Le FLoch Isabelle. "Absorption et régénération de l'azote dans les systèmes côtiers : réponse à des apports massifs de nitrate." Brest, 2001. http://www.theses.fr/2001BRES2001.
Duwig, Céline. "Etude des transferts d'eau et de nitrate dans les sols ferrallitiques de Maré (Nouvelle-Calédonie) : risques de pollution des lentilles d'eau douce." Phd thesis, Université Joseph Fourier (Grenoble), 1998. http://tel.archives-ouvertes.fr/tel-00718715.
Floch, Grégoire. "Composition isotopique du nitrate dans le névé antarctique : avancées et nouvelles perspectives sur les phénomènes post-dépôts /." [S.l.] : [s.n.], 2006. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
Rose, Jérôme. "Interactions entre le fer (III) et les ions nitrate, phosphate et carboxylate : mécanismes de complexation, nucléation, croissance." Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL097N.
Lacombe, Simon. "Diminution des pertes du nitrate par lixiviation et augmentation de la diversité microbienne dans les systèmes agroforestiers." Mémoire, Université de Sherbrooke, 2007. http://savoirs.usherbrooke.ca/handle/11143/4786.
Prado, Pano Blanca Lucia. "Etude du mouvement de l'eau et du transfert réactif du nitrate dans les sols volcaniques du bassin versant élémentaire de la Loma, Mexique." Université Joseph Fourier (Grenoble), 2006. http://www.theses.fr/2006GRE10083.
Understanding nitrate fate processes in the volcanic soils of an elementary catchment "La Loma", is necessary to evaluate the impact of agricultural activities on the water quality and to define strategies to protect the water resources of the Valle de Bravo basin. This agricultural basin provides 15% of drinking water supplied to the metropolitan zone of Mexico City. The soil of "La Loma" is an Andosol, with a mineralogy characterized by amorphous constituents like allophane. The soil presents variable charge; where allophane and organic matter are the main contributors. Nitrate adsorption in the soil, studied in a static way and dynamic way, is linear and instantaneous in the concentrations range studied (4 to 20 mM). Soil structure and pore network geometry strongly influence the fate of dissolved nutrients. Solute transport through packed and intact columns shows two different behaviors: physical equilibrium and non-physical equilibrium respectively. Tillage practices affect the structure and the pore network of the first 30 cm of the soil profile. Infiltrometry tests highlighted two different behaviors in the soil profile: at the soil surface none of the analysis methods gave good results due to the high spatial variability of the soil properties following the agricultural practices; in depth the hydraulic conductivity varies from 0. 006
Beaujouan, Véronique. "Modélisation des transferts d'eau et d'azote dans les sols et les nappes. Développement d'un modèle conceptuel distribué. Applications à de petits bassins versants agricoles." Rennes, ENSA, 2001. http://www.theses.fr/2001NSARD035.
Affolter, Céline. "Etude des modes d'action d'additifs sur les phénomènes de dissolution et de cristallisation de sels hygroscopiques : Application au mottage du nitrate d'ammonium." Compiègne, 2003. http://www.theses.fr/2003COMP1467.
Caking is defined as spontaneous, non desired agglomeration of powders taking place particularly during storage periods. The adsorption of air moisture and capillary condensation at contact points are at the origin of the formation of liquid bridges between neighbouring particles. In case of hygroscopic solids, particularly of ammonium nitrate, the solution formed is saturated. The variation of the ambient conditions can cause the formation of solid bridges by mechanisms of dissolution and recrystallization. We were particularly interested in the modes of action of additives on the formation by dissolution as well as on the crystallization of interparticle bridges. We evaluated the influence of fuchsin acid and of eight commercial anti-caking agents, on crystals and prills of ammonium nitrate respectively. Our study focus on the behaviour of the hygroscopic powder with respect to the relative humidity. Kinetics of dissolution and crystallization were followed by gravimetric analysis. The mechanical strength of the crystalline bridges was estimated by a compression test developed at the laboratory and results are compared to an industrial test. Two distinct behaviours were observed: fuchsin acid tends to modify the morphology of crystals grown between the particles without influencing the water vapour sorption kinetic. On the other hand, the industrial additives limit water absorption. Nevertheless the correlation of caking test and the amount of water absorbed does not show that the prill's tendency to agglomerate increases with increasing amount of absorbed water
MARTIN, Charlotte. "Mécanismes hydrologiques et hydrochimiques impliqués dans les variations saisonnières des teneurs en nitrate dans les bassins versants agricoles. Approche expérimentale et modélisation." Phd thesis, Université Rennes 1, 2003. http://tel.archives-ouvertes.fr/tel-00003939.