Dissertationen zum Thema „Composition isotopique du carbone“
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BENTALEB, ILHEM. „Les processus physiologiques dans la couche euphotique et la composition isotopique du carbone organique du phytoplancton : relation entre la composition isotopique du carbone organique et le gaz carbonique dissous. applications a la paleoclimatologie“. Paris 6, 1994. http://www.theses.fr/1994PA066045.
Der volle Inhalt der QuelleTarits, Corinne. „Etude des variations de composition isotopique du carbone et de l'oxygène dans le domaine de la précipitation spontanée homogène du carbonate de calcium : modélisation du comportement isotopique du carbone dans ce domaine“. Paris 5, 1990. http://www.theses.fr/1990PA05P617.
Der volle Inhalt der QuelleKanpanon, Nicha. „La composition isotopique en carbone est-elle un indicateur écophysiologie pertinent de l’efficience d’utilisation de l’eau de l’hévéa ?“ Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0240/document.
Der volle Inhalt der QuelleThe rubber (Hevea brasiliensis) plantations extend to non-traditional area in Thailand where dryer conditions has been reported to impair the growth of rubber trees and latex production. Physiological parameters helpful for breeding adapted genotypes are required, such as water use efficiency (WUE). Carbon isotope discrimination is widely used as a proxy for WUE that can easily be used for selection and breeding programs for drought tolerance. Leaf δ13C and leaf gas exchange were measured on young saplings of 10 rubber clones growing in pot in a common garden. The range of leaf δ13C among 10 clones was narrow and the correlation between δ13C and WUEi was significant under high vapour pressure deficit only, which means the prediction of WUE by δ13C would have low precision. There were large δ13C variations among the genotypes at all seasons in a collection of 49 wild genotypes of rubber in Northeastern Thailand. δ13C was rather stable with a good correlation between rainy and dry season. The genetic variability of δ13C is promising for breeding if a good correlation between δ13C of leaf and WUE can be established. The lack of correlation between δ13C of latex (δ13C-L) and of leaf soluble compounds (δ13C-S) collected from tapped and untapped 20 year-old rubber trees suggests that recent photosynthates are mixed in the large pool of stored carbohydrates that are involved in latex regeneration after tapping. Thus δ13C of latex is not a relevant indicator of WUE of rubber trees
Fusetti, Luc. „Elaboration d'un modèle cinétique en vue de predire la composition moléculaire et isotopique des gaz naturels issus du craquage des hydrocarbures“. Paris 6, 2009. http://www.theses.fr/2009PA066262.
Der volle Inhalt der QuelleLaunois, Thomas. „Modélisation de la composition isotopique des cernes d'arbres (13C et 18O) et des transferts de COS entre l'atmosphère et la biosphère continentale pour quantifier les flux bruts de carbone“. Thesis, Versailles-St Quentin en Yvelines, 2014. http://www.theses.fr/2014VERS0039/document.
Der volle Inhalt der QuelleIn the context of global climate change, the behavior of the terrestrial biosphere can be durably affected by the increased frequency and intensity of extreme climatic events, which can decrease the photosynthetic assimilation of carbon and/or increase the respiration rate of the ecosystems. Therefore, quantifying the carbon storage capacity of the ecosystems and predicting their sensitivity to climate changes strongly rely on our capacity to separately estimate the photosynthesis and respiration rates at different scales. The gross primary productivity (GPP) is however not directly measurable. Indirect approaches have been proposed to estimate the biospheric gross fluxes (GPP and respiration), combining for instance stable isotopologues of CO2 (13C and 18O), and, more recently, the measure of carbonyl sulfide (COS) concentrations in the atmosphere. In this context, my PhD work followed two complementary approaches. In the first approach, isotopic measurements and tree-ring widths were used, because both of them are linked to the photosynthetic activity. The inter-annual variations of the photosynthetic fluxes simulated with the ORCHIDEE continental biosphere model were evaluated and compared with in situ measurements. The second approach consisted in using atmospheric measurements of OCS concentrations and in exploring their potential to constrain the current estimates of the GPP in dynamic global vegetation models (DGVM), by (1) establishing a new global budget of sources and sinks of this gas, (2) optimizing the source and sink terms of this cycle and (3) estimating the potential of this new tracer to validate/invalidate the simulated GPP when using current DGVMs
Bartholomé, Jérôme. „Déterminisme génétique de la dynamique de croissance et de la composition isotopique du carbone chez l'Eucalyptus en réponse aux variations environnementales“. Thesis, Montpellier, SupAgro, 2014. http://www.theses.fr/2014NSAM0011/document.
Der volle Inhalt der QuelleScenarios of climate changes forecast an increase in frequency and intensity of droughts, related to an increase of global temperatures and changes in rainfall distribution. Growth of forest trees highly depends on water availability and will be significantly impacted by these changes. The understanding of the impact of genetic and environmental factors on the growth dynamics is a major challenge to ensure production levels of future planted forests. Eucalyptus, thanks to its rapid growth and the availability of genetic and genomic resources, is a perfect model to conduct this research.The objective of this thesis is to characterize the genetic architecture of growth dynamics in Eucalyptus at different time scales, in relation with: (i) environmental changes, including changes in water availability, and (ii) isotopic composition of carbon (delta 13C), a character associated with water-use efficiency. To this end, an interspecific cross between E. urophylla x E. grandis was studied in four experimental trials in the Republic of Congo. Our approach, based on mapping of quantitative trait loci (QTL), combines (i) a high-throughput genotyping, (ii) a characterization of inter and intra-annual growth dynamics and delta 13C, as well as a continual measurement of stem radial micro-variations and (iii) a continual characterization of environmental factors.First of all, this work led to the construction of the first high-resolution genetic maps in Eucalyptus, improving the sequence of the reference genome. Then, the analysis of genetic architecture of delta 13C enabled the identification of positional candidate genes which might be involved in the variation of this trait. Finally, inter and intra-annual characterization of growth dynamics highlight that genetic architecture of adult growth is structured by responses to the environment at the juvenile stage. These responses were then analyzed using daily profiles of stem radial micro-variations, which enabled the characterization of the genetic determinants of response to the environmental factors at the juvenile stage.Our results highlight the importance of considering growth as a dynamic trait, not only to understand its genetic basis, but also to select in a changing environment
Fiorini, Sarah. „Effet de l'augmentation de la pression partielle du dioxyde de carbone et de la température sur le phytoplancton calcifiant (coccolithophoridés)“. Paris 6, 2009. http://www.theses.fr/2009PA066586.
Der volle Inhalt der QuelleLaunois, Thomas. „Modélisation de la composition isotopique des cernes d'arbres (13C et 18O) et des transferts de COS entre l'atmosphère et la biosphère continentale pour quantifier les flux bruts de carbone“. Electronic Thesis or Diss., Versailles-St Quentin en Yvelines, 2014. http://www.theses.fr/2014VERS0039.
Der volle Inhalt der QuelleIn the context of global climate change, the behavior of the terrestrial biosphere can be durably affected by the increased frequency and intensity of extreme climatic events, which can decrease the photosynthetic assimilation of carbon and/or increase the respiration rate of the ecosystems. Therefore, quantifying the carbon storage capacity of the ecosystems and predicting their sensitivity to climate changes strongly rely on our capacity to separately estimate the photosynthesis and respiration rates at different scales. The gross primary productivity (GPP) is however not directly measurable. Indirect approaches have been proposed to estimate the biospheric gross fluxes (GPP and respiration), combining for instance stable isotopologues of CO2 (13C and 18O), and, more recently, the measure of carbonyl sulfide (COS) concentrations in the atmosphere. In this context, my PhD work followed two complementary approaches. In the first approach, isotopic measurements and tree-ring widths were used, because both of them are linked to the photosynthetic activity. The inter-annual variations of the photosynthetic fluxes simulated with the ORCHIDEE continental biosphere model were evaluated and compared with in situ measurements. The second approach consisted in using atmospheric measurements of OCS concentrations and in exploring their potential to constrain the current estimates of the GPP in dynamic global vegetation models (DGVM), by (1) establishing a new global budget of sources and sinks of this gas, (2) optimizing the source and sink terms of this cycle and (3) estimating the potential of this new tracer to validate/invalidate the simulated GPP when using current DGVMs
Gontharet, Swanne. „Les suintements hydrothermaux froids et leur impact sur l'écosystème benthique“. Paris 6, 2006. http://www.theses.fr/2006PA066364.
Der volle Inhalt der QuelleKallel, Nejib. „Variation de la composition isotopique de l'oxygène et du carbone des foraminifères : traceur de la circulation océanique pendant le dernier maximum glaciaire et lors de la dernière déglaciation“. Paris 11, 1988. http://www.theses.fr/1988PA112124.
Der volle Inhalt der QuelleOxygen and carbon isotopic composition of benthic foraminifera from different oceanic sediment cores have been used to reconstruct the pattern of intermediate and deep ocean circulation during last glacial maximum (18,000 years BP) in the Indian and Pacifie oceans. Results show that the glacial oceanic circulation was significantly different from the modern one. A deep hydrological front separated intermediate water of the Indian and Equatorial Pacifie from underlying deep water. Glacial intermediate water was weil ventilated and has approximately the same temperatures than today. By contrast, glacial deep water was cooler by severa!degrees than modern one. In the Pacifie ocean, deep water was more ventilated than that in the Southern Indian ocean indicating the formation of relatively ventilated deep water in the South Pacifie or the increase of the influence of the North Pacifie Intermediate Water. As late as 12,500 yr BP deep oceanic circulation was similar to the glacial one. The decrease of the influence of the North Pacific Intermediate Water has appeared at about 12,500 yr BP and the onset of the active formation of the North Atlantic Deep Water has appeared at about 9,000 yr BP. Holocene conditions have been reached at about 8,000 yr BP in ali oceans and at ali water depths
Kallel, Nejib. „Variation de la composition isotopique de l'oxygène et du carbone des foraminifères un traceur de la circulation océanique au dernier maximum glaciaire et lors de la dernière déglaciation /“. Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376146455.
Der volle Inhalt der QuelleTarantola, Alexandre. „Les mécanismes rédox contrôlant la chimie du carbone dans les fluides de l'anchi-métamorphisme : composition des paléofluides, géochimie isotopique, cristallochimie des minéraux phylliteux dans la partie externe des alpes centrales (Suisse)“. Nancy 1, 2005. http://www.theses.fr/2005NAN10163.
Der volle Inhalt der QuelleThis works characterizes the mechanisms at which occurs the transition between CH4- and H2O- dominated fluid zone in the anchi-metamorphic rocks of the External part of Central Alps, Switzerland. Fluid inclusion trapped in fibre quartz during crack-and-seal mechanism record increasing metamorphic conditions during Alpine orogene. The end of the CH4-zone is characterized by a marked increase of CO2 at 270 ± 5°C. The decrease of CH4 and CO2 in the H2O-zone is contemporaneous with presence of calcite, totally filling Alpine fissures. Isotopic fractionation (delta13C) between methane and calcite is in agreement with homogenisation temperatures of fluid inclusion. DeltaD(H2O) and delta13C(CO2) values of fluid inclusions at the end of the CH4-zone characterise methane oxidation. In agreement with Mössbauer spectroscopy and EELS analyses, neoformation of chlorite and muscovite from detrital biotite is considered as the Fe-reduction driving force of the oxidation of fluid
Denis, Marie. „Mécanismes de solubilisation et transfert de matières organiques dissoutes à l'échelle d'un bassin versant agricole : apport de l'étude de la composition moléculaire“. Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S045/document.
Der volle Inhalt der QuelleDissolved organic matter (DOM), as sources of nutrient or pollutant dissemination pathway are implied in numerous environmental issues. Although DOM have been the subject of numerous studies for several decades, the mechanisms implied for their solubilization and their transport from soils to aquatic systems are still a matter of discussion. Based on DOM molecular composition determined using thermally assisted hydrolysis and methylation –gas chromatography – mass spectrometry (THM-GC-MS), this thesis aims to provide a better understanding of their solubilization and transfer mechanisms at the scale of an agricultural headwater catchment. This work was conducted on the experimental headwater catchment of Kervidy-Naizin (France, Environmental Research Observatory AgrHys) in order to determine the processes implied at two temporal scales. At the scale of a rain event, this work has clarified the impact of hydrological conditions on the DOM dynamics. At annual scale, the use of carbon isotope signature (δ13C) and DOM molecular composition allowed to clarify the DOM transfer mechanisms at the slope scale. The use of THM-GC-MS appears to be a suitable tool for the study of DOM dynamics. The results thus obtained allowed to highlight the role of hydrological conditions and in particular the water-table level in the solubilization and transfer of DOM
Rabarijaona, Arivoara. „L'efficience intrinsèque d'utilisation de l'eau (WUEi) du chêne sessile conditionne-t-elle sa résilience à la sécheresse ?“ Electronic Thesis or Diss., Paris, AgroParisTech, 2023. http://www.theses.fr/2023AGPT0016.
Der volle Inhalt der QuelleAssisted migration constitute a possibility to adapt forest ecosystems face to the increase in drought intensity and frequency. However, this strategy requires identification of drought-resistant populations and characterization of the diversity within them. Water use efficiency (WUE) is a key trait to assess for this choice, as it reflects a trade-off between carbon assimilation and water loss through transpiration. By combining dendrochronology and stable isotope analysis, this thesis investigates the effect of WUE on the growth performance and resilience to drought of sessile oak (Quercus petraea).Firstly, WUE was compared among 16 populations whose individuals, from seeds originating from sites along a wide range of pedoclimate gradient, had grown in the common garden Sillegny. Significant differences in WUE were found among these populations, but these differences were not correlated with the pedoclimatic conditions of the sites of origin. However, populations from provenances with sandy soils showed a larger increase in WUE in response to the drought of 2003 (compared to the wet year of 2000) than populations from provenances with silty soils. In addition, trees with higher WUE showed larger radial growth only in wet years. Although these results suggest an adaptation of the sessile oak, reflected by the plasticity of WUE to drought, the variability of WUE within populations was higher compared to the differences among populations.Then, the phenotypic variability of WUE was studied within two populations with contrasting soil and climate conditions, at the Blois (wet) and the Harth (dry) sites. All the trees within each plot were sampled, with a particular focus on the relationship between WUE and radial growth. While stomatal control appeared to be the key factor in inter-annual variations in WUE, the inter-individual (intra-annual) variability in WUE was driven more by net CO2 assimilation, which is strongly affected by tree social status. The intra-annual relationships between WUE and growth appeared more significant as the competition among trees within the stand intensified (particularly when trees become mature), and when light availability became a limiting factor rather than water (in a humid site, at Blois).Finally, the effect of WUE expressed by trees at a young age on growth trajectory was assessed within the Blois and the Harth stands. At the Harth site, trees with higher WUE during their young age were the most dominant in 2021, suggesting selection for higher WUE in dry environment. In contrast, at the Blois site, the effect of WUE at the young age on the social status of the trees ceased after 60 years. The response of trees to drought was not significantly affected by WUE at the young age at the Blois site and only during the first decades at the Harth site. Moreover, the plasticity of WUE to drought might play a diminishing role in the selection process as trees age and were exposed to changing environmental conditions.WUE is a complex trait influenced by multiple factors, including genetics, microenvironmental conditions, and tree age. Given that intra-population variations were more pronounced than differences among populations, and that the relationship between WUE and resilience to drought was tenuous, the selection of drought-adapted sessile oak populations cannot be only based on WUE
Sangely, Laure. „Développement de l'analyse in situ de la composition isotopique du carbone organique par sonde ionique : apports à l'étude de l'origine des bitumes associés aux gisements d'uranium de l'Athabasca (Canada) et du Witwatersrand (Afrique du Sud)“. Vandoeuvre-les-Nancy, INPL, 2004. http://www.theses.fr/2004INPL074N.
Der volle Inhalt der QuelleLiétard, Cécile. „Utilisation des mollusques bivalves comme enregistreurs des paramètres de l'environnement marin côtier et profond“. Paris 6, 2007. http://www.theses.fr/2007PA066353.
Der volle Inhalt der QuelleBrandon, Margaux. „Les changements majeurs de la productivité biologique au cours du Quaternaire et leurs impacts sur les cycles du carbone et de l’oxygène“. Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASJ010.
Der volle Inhalt der QuelleDuring glacial-interglacial cycles of the Quaternary, the atmospheric CO₂ (pCO₂) concentration is associated with important variations, in particular during transitions between glacial and interglacial periods, also called terminations, with increases of up to 100 ppm of pCO₂ in a few thousand years. While the roles of oceanic circulation and sea-ice cover on pCO₂ are studied for several years now, little is known on the impact of biological productivity. The goal of this thesis is to reconstruct the past changes in biological productivity and to estimate their contributions on atmospheric pCO₂ variations over the last 800 000 years (ka), with particular attention to Termination V (~425 ka) and Marine Isotope Stage (MIS) 11, the interglacial period around 400 ka. Two different approaches were combined to reconstruct global and local variations of biological productivity. Measurements of Δ¹⁷O of O₂ in the air trapped in the Antarctic EPICA Dome C ice core between 400 and 800 ka allowed to complete the pre-existing record and trace back variations of global biosphere productivity expressed in oxygen fluxes over the past 800 ka. Micropaleontological (coccoliths, foraminifera) and geochemical (TOC, CaCO₃, XRF) analyses were performed on a sediment core of the Indian sector of the Southern Ocean (MD04-2718) to reconstruct the changes in biological pump efficiency over the past 800 ka. The results obtained during this thesis showed that, at the scale of glacial-interglacial cycles, global biospheric productivity and Southern Ocean carbonate production are more important during interglacial periods compared to glacial periods, minimizing the impact of marine organic productivity on atmospheric pCO₂. Termination V and MIS 11 register the strongest biosphere productivity of the past 800 ka and the highest marine carbonate production of the past 9 interglacial periods in the Southern Ocean. While the important carbonate production is a source of CO₂ for the atmosphere, the rise in biosphere productivity would counterbalance the increase in pCO₂ through photosynthesis
Triolo, Roberta. „Hierarchy of factors impacting grape berry mass at different scales and its direct and indirect effects on grape and wine composition“. Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0336/document.
Der volle Inhalt der QuelleFinal berry mass is the result of the integrated effect of several factors. They also influence berry composition. The present work was designed to study the simultaneous effect of major factors influencing berry mass and composition, to hierarchize their impact at different scales, to distinguish their direct and indirect effect on berry composition and to compare the profile of wines made from large and small berries. The study was carried out simultaneously on two vineyards located in the Saint Emil ion (France) and Alcamo (Sicily) areas, during 2014 and 2015. On the first site, vines were planted on two soil types, while on the second site two different irrigation treatments were applied. Depending on the scale, some factors homogeneously impacted the berry mass and composition. At the intra-parcel scale, vine water status represented the most impacting factor, while berry seed number did not have significant effect. Opposite results were obtained when the investigation was carried out at the intra-bunch and intra-plant scales. At large scale, factors impacted directly and indirectly berry compounds and grape juices and wines produced from smaller berries were more concentrated. Neither at intra-bunch, nor at intra-plant scales, berry size effect on juice composition was significant. Only anthocyanin concentration was related to berry size at all scales. This fact was particularly obvious in berries produced under limited water conditions. Water deficit increased the skin to flesh ratio, independently of berry size. This means that small and large berries, produced from a single parcel with homogenous water uptake conditions, tend to have similar enological profiles
Kahane, Claudine. „Observations millimétriques de molécules circumstellaires : de la recherche de nouvelles espèces, à la mesure d'abondances isotopiques“. Phd thesis, Grenoble 1, 1989. http://tel.archives-ouvertes.fr/tel-00724537.
Der volle Inhalt der QuelleCachier-Rivault, Hélène. „Approche isotopique du cycle atmospherique du carbone particulaire“. Paris 7, 1987. http://www.theses.fr/1987PA077061.
Der volle Inhalt der QuelleCachier-Rivault, Hélène. „Approche isotopique du cycle atmosphérique du carbone particulaire“. Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376035474.
Der volle Inhalt der QuelleGilbert, Alexis. „Méthodologies pour l'étude du fractionnement isotopique photosynthétique et post-photosynthétique par RMN 13C isotopique“. Nantes, 2010. http://www.theses.fr/2010NANT2049.
Der volle Inhalt der QuelleA methodology has been developed that makes possible the determination of the site specific carbon-13 isotopic composition of glucose, fructose and sucrose using isotopic 13C NMR. The derivatization of sugars as their acetonides is a prerequisite to accessing the desired information. Once the protocol for the derivatization was perfected, the methodology can attain a precision of 1‰ or better. Analyses of ethanols derived from sugars by fermentation show a good correlation with results obtained by the methodology developped. The ethanol molecule has also been used as a probe to show the influence of climatic parameters (temperature, sunshine, rainfall) on the intra-molecular 13C isotope distribution in sugars from grapes. Moreover, results for sugars or starch from plants having C3 or C4 metabolism show there to be an intramolecular 13C distribution characteristic of the type of carbon assimilatory pathway exploited. The hypothesis proposed here indicates that the CO2 assimilation mode is not the only factor affecting the intra-molecular 13C distribution in sugars. It appears that isomerisation steps (involving trioses phosphates or hexoses phosphates) are crucial in terms of isotopic fractionation in the sugars produced during photosynthesis. We have therefore measured the isotope effects associated with the transformation of glucose to fructose, catalysed by glucose isomerase. A clear equilibrium isotope effect is observed, which is shown to be responsible for the C-1 enrichment and the C-2 depletion of glucose, and a significant kinetic isotope effect on the C-2 of glucose is also seen during the conversion of fructose to glucose
MUSSILLON, THIBAUD. „Separation isotopique du carbone 13 par photodissociation selective du formaldehyde“. Paris 11, 1998. http://www.theses.fr/1998PA112390.
Der volle Inhalt der QuelleMarchandise, Sandra. „Répartition et composition isotopique de la florencite dans l'océan“. Versailles-St Quentin en Yvelines, 2012. http://www.theses.fr/2012VERS0059.
Der volle Inhalt der QuelleThorium (Th), Uranium (U), Rare-Earths (REE) and Hafnium (Hf) are trace elements and isotopes widely used in oceanography to trace particulate matter processes but their bearing phases are still unknown. This work is the first inventory of U-Th-REE-Hf rich phases in DYFAMED suspended particles and deep-sea sediments, in the western Mediterranean Sea. In DYFAMED sediments, zircon stays the major carrier phase of Hf. HREE are carried by xenotime and zircon in sediments, Therefore, they have a strong impact on the Lu/Hf systematic. Monazite, allanite, florencite and apatite are minor carriers of U, Th and LREE in the ocean (also zircon for U). Nevertheless, they have very heterogeneous U/Th ratio which could explain variations of 230Th/232Th ratio observed. Nd isotopic signature measurements shows that, in DYFAMED sediments and water column, inputs from the Var River are the more important compared to Saharan aerosols
Clog, Matthieu. „Concentration et composition isotopique en hydrogène du manteau terrestre“. Paris 7, 2010. http://www.theses.fr/2010PA077209.
Der volle Inhalt der QuelleConstraining the concentration and isotopic composition of hydrogen in Earth's mantle brings crucial insights on the global water cycle and the nature of mantle heterogeneities. For this purpose, glassy rims of basalts are the best samples. In this study, 170 samples from 4 oceanic ridges and 2 hotspots were analysed for water content and ô D. During this work, we showed that using platinum crucibles to extract the volatiles was the cause of an analytical bias in earlier data. The use of silicate tubes was thus prefered. δ D re-measured on samples previously analyzed using platinum crucibles are, on average, 15%o higher. The δ D and the H2O/Ce ratio are hétérogeneous, both between areas and locally, and caracterize the sources. The source of N-MORB contains 175+/-70 ppm of water and has a δ D of -61+/-6%o. MORB from the Altantic ocean are richer in water (-250 ppm in the source) and D ( δ D—57%o), than those from thé South-East Indian (H2O~140 ppm and δ DS\simS-63%o), illustrating different mixing processes, also seen through the Pb/Ce ratios. The study of the MORB from the South-West Indian ridge showed that δ D and H2O/Ce are sensitive to metasomatism. The concentrations of water in E-MORB and OIB sources are higher and more variable (from 250 to 700 ppm). The ô D of water- and incompatible elements-enriched sources range from -70 to -40%o, showing as much variations as depleted sources. Confrontation with the isotopic compositions of Ne, Pb, Sr and Nd shows that the resevoir containing the primitive rare gases cannot be water-rich, and is thus different from the FOZO. Therefore, efficient recycling of water with no modification of its isotopic composition in hydrogen at subdcution zone can occur at some subduction zones
BEAUMONT, VALERIE. „Compositions isotopiques de l'azote et du carbone de la matiere organique sedimentaire : une etude des silex precambriens“. Paris 7, 1994. http://www.theses.fr/1994PA077119.
Der volle Inhalt der QuelleLourantou, Anna. „Contraindre l'augmentation en dioxyde de carbone (CO2) lors des déglaciations basés sur son rapport isotopique stable du carbone (δ13CO2)“. Phd thesis, Grenoble 1, 2008. http://www.theses.fr/2008GRE10286.
Der volle Inhalt der QuelleThe present work is based on the measurement of carbon dioxide (CO2) and its stable isotopic ratio δ13CO2 in air bubbles trapped in polar ice (EPICA core, Dome C, in Antartica, EDC). We focus on rapid transitions from glacial to interglacial periods. δ13CO2 allows the partitioning of the origin of CO2 between oceanic and terrestrial sources. This study documents with high temporal resolution the evolution of CO2 and δ13CO2 during the two last deglaciations. The last deglaciation is characterized by an increase of 80 ppmv CO2, coeval with a decrease of 0. 6 ‰ in δ13CO2. Larger amplitudes were observed during the penultimate deglaciation (+110 ppmv CO2 with a 0. 9 ‰ decrease in δ13CO2). The measurements, interpreted with two carbon cycle models (BOXKIT and BICYCLE) are consistent with the following scenario. First, a Southern Hemisphere warming triggers an increase in atmospheric CO2. This provokes a biological and physical reorganization of the Southern Ocean which reduces δ13CO2. Last, this reorganization propagates to the north with a delayed impact of terrestrial biosphere during the Bølling/Allerød (B/A). These results obtained for the first time from the EDC core allowed to propose a scenario on the causes of deglaciations. A series of tests, based on ice of different properties, provided a validation of our extraction method
Lourantou, Anna. „Contraindre l'augmentation en dioxyde de carbone (CO2) lors des déglaciations basés sur son rapport isotopique stable du carbone (δ13CO2)“. Phd thesis, Université Joseph Fourier (Grenoble), 2008. http://tel.archives-ouvertes.fr/tel-00370658.
Der volle Inhalt der QuelleCette étude documente à haute résolution temporelle l'évolution du CO2 et du δ13CO2 pendant les deux dernières déglaciations. La dernière déglaciation est caractérisée par une augmentation en CO2 de 80 ppmv, accompagnée par une diminution en δ13CO2 de 0.6 ‰. Des amplitudes plus importantes sont observées durant la pénultième déglaciation (+110 ppmv CO2, accompagnés pas une diminution en δ13CO2 de 0.9 ‰).
Les mesures, interprétées avec deux modèles du cycle du carbone (BOXKIT et BICYCLE) sont cohérentes avec le scénario suivant. Dans un premier temps, un réchauffement de l'hémisphère sud initie une augmentation du CO2 atmosphérique. Ceci entraîne une réorganisation biologique et physique de l'océan austral qui diminue le δ13CO2. Enfin, cette réorganisation se propage vers le nord avec un impact retardé de la biosphère continentale, pendant le Bølling/Allerød (B/A).
Ces résultats obtenus pour la première fois dans la carotte EDC, ont permis de proposer un scénario sur les causes des déglaciations. Une série de tests, basée sur des glaces de différentes propriétés a fourni une validation de notre méthode d'extraction.
Chiquet, Arnaud. „Géochimie isotopique des calcrètes“. Aix-Marseille 3, 1999. http://www.theses.fr/1999AIX30024.
Der volle Inhalt der QuelleHoussein-Ofleh, Bouh. „Etude de l'aquifère basaltique de Djibouti et des aquifères adjacents : approche hydrochimique et isotopique“. Paris 11, 2006. http://www.theses.fr/2006PA112120.
Der volle Inhalt der QuelleBotosoa, Eliot-Patrick. „Protocoles analytiques pour l'étude de la vanilline par RMN 13C isotopique en abondance naturelle : reproductibilté méthodologique, purification, origines du fractionnement isotopique“. Nantes, 2008. http://www.theses.fr/2008NANT2020.
Der volle Inhalt der QuelleIsotopic 13C NMR can measure the site by site isotopic deviation in 13C, making it possible to study the mechanism of the biotransformation of ferulic acid to vanillin. A priori, it was necessary to developed conditions for the reliable measurement of very small deviations with sufficient precision. Hence, it was show that, during the purification of vanillin and ferulic acid by silica gel column chromatography, unexpected site-specific isotopic deviation was introduced in different fractions recovered from the eluting peak. Both normal and inverse effects occurred, indicating that each isotopomers has a characteristic elution profile due to specific interactions with the stationary/mobile phases used. Thus, insights into the causes of non-covalent isotopic fractionation in chromatography have been obtained. The technique was applied to the biotransformation of ferulic acid to vanillin by micro-organisms, Streptomyces setonii and Amycolatopsis sp. These experiments provided clear evidence supporting the prior hypothesis of a role of a ‘hydroquinone’ intermediate in the C6C3 to C6C1 chain-shortening mechanism. This conclusion was supported by theoretical calculations of the predicted isotope effects. Future developments will include studies of the role of non-covalent interactions in isotopic fractionation, notably within the context of interactions between pollutants and contaminated soils, and the development of a general method for the authentication of the origin of natural vanillin through the analysis of the site-by-site deviations in 13C determined by 13C NMR
Cartigny, Pierre. „Concentration, composition isotopique et origine de l'azote dans le manteau terrestre“. Paris 7, 1997. http://www.theses.fr/1997PA077186.
Der volle Inhalt der QuelleAPPORA, GNEKINDY IRMA. „Etude experimentale du fractionnement isotopique du carbone et de l'oxygene dans les systemes co 2-carbonates liquides : application au contexte carbonatitique“. Paris 7, 1998. http://www.theses.fr/1998PA077170.
Der volle Inhalt der QuelleYang, Chengfan. „Li isotope study of Yangtze River sediments : new constraints on climate, weathering and carbon cycle relationships“. Electronic Thesis or Diss., Sorbonne université, 2020. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2020SORUS433.pdf.
Der volle Inhalt der QuelleIn order to better understand the weathering-climate feedback, a series of studies was carried out in the Changjiang (Yangtze) Basin. First, the operation of the Three Gorges Dam (TGD) changed downstream sediment geochemical compositions. Before 2003, large amounts of upstream-derived sediments deposited and experienced further weathering in the mid-lower basin. Since 2003, strong riverbed sediment resuspension changed the roles of the mid-lower reaches from important sinks to major sources of sediments delivered to the sea. As a consequence, an intensified weathering intensity of downstream sediment was observed.Second, dissolved δ7Li exhibit a conservative behavior in the Changjiang Estuary. During the process of SPM transported offshore, weathering product flocculated and deposited, while primary minerals resuspended. The combined effect resulted in the UCC-like SPM δ7Li values. There is a Li isotope fractionation between the dissolved load and exchangeable phase. However, this process shows negligible impact on δ7Li of dissolved load and particulates. Third, weathering response to climate is complex in large river basins. During the Younger Dryas, the positive excursion of clay δ7Li is consistent with enhanced incongruent weathering, in response to temperature cooling. The minor variation of clay δ7Li at 11 – 2 ka likely indicate stable weathering and mile climate variation. Over the last 2 kyr, the fluctuation of clay δ7Li is mostly caused by intensification of human activities. In summary, this thesis sheds new lights on the weathering-climate feedback over geologic past, and provides perspectives on how human activities affect natural processes
Diomande, Gbe Gondo Didier. „Contribution des méthodes spectroscopiques et isotopiques à la caractérisation géographique et phénotypique du cacao“. Nantes, 2014. https://archive.bu.univ-nantes.fr/pollux/show/show?id=fd4e7f5d-6094-444e-b12a-043f6c632eb5.
Der volle Inhalt der QuelleThe cocoa tree (Theobroma cacao L. ) is a plant of the family Sterculiaceae. The fruit, called the pod, contains beans that are used in the manufacture of chocolate. Fraudulent production practices are making consumers increasingly suspicious both of the sanitary quality of foodstuffs and of the origin of production (organic, GM, etc. ). Faced with this problem, the new European legal ruling 178/2002, effective since 1 January 2005, imposes traceability for foodstuffs. This thesis is positioned within this context. The analysis of the multi-isotope content (15N, 13C) of 61 samples of cocoa obtained from 22 countries, of which 37 samples are from the Ivory Coast, has been carried out. By statistical analysis of the data, it is shown that the isotopic parameters δ15N and δ13C for the whole cocoa beans, and those from different parts of the bean, are responsible for the discrimination found between samples from different continents, from three villages in the Ivory Coast, and between the varieties Forastero and Trinitario. Fermentation of cocoa is the process that most influences the quality of the beans. A study of the influence of fermentation on the isotopic composition in δ15N and δ13C showed either enrichment or impoverishment for the bean and for different parts of the bean, with the exception of theobromine, for which no isotopic fractionation was found. As a result, theobromine was used in isotopic quantitative 13C NMR as molecular probe for the characterization of the geographical origin of cocoa. A methodology has been developed which allows the measurement of the intramolecular 13C distribution in theobromine with sufficient accuracy, subsequent to its transformation into caffeine. New parameters were obtained which not only allowed confirmation of the distinct geographical origins of different cocoa samples, but also to differentiate cocoa from products containing caffeine (tea and coffee). An exploratory study was also carried out measuring the 18O content of theobromine by irm-MS, with the same objective in mind. Finally, cocoa butter, which is one of the most important matrices in the beans, was analyzed by 13C NMR in the framework of the methodology “metabolomics”, notably targeting the glycerol
Caillon, Nicolas. „Composition isotopique de l'air piégé dans les glaces polaires : outil de paléothermométrie“. Paris 6, 2001. http://www.theses.fr/2001PA066279.
Der volle Inhalt der QuelleBrunet, Frédéric. „Variations de la signature isotopique (delta)13 C du carbone inorganique dissous dans les rivières et les fleuves“. Toulouse 3, 2004. http://www.theses.fr/2004TOU30228.
Der volle Inhalt der QuelleThe scientific objective of this work is to better understand the riverine carbon transfers to the oceans and to identify the different biogeochemical processes controlling these transfers using carbon isotopic signature (d13C). In order to do that, 25 watersheds have been investigated in the world, going from small catchments to large river basins. The results emphasize the major control of CO2 degassing to the atmosphere and of organic carbon oxidation (allochtonous and autochtonous) on the riverine d13CDIC. The average isotopic signature d13CDIC of the inorganic carbon riverine flux into the oceans has been estimated in this study to be -11,8. Finally, a first approach of a numerical model (d-Carb) has been developed to simulate the d13CDIC evolution in rivers
CREACH, VERONIQUE. „Origines et transferts de la matiere organique dans un marais littoral : utilisation des compositions isotopiques naturelles du carbone et de l'azote“. Rennes 1, 1995. http://www.theses.fr/1995REN10002.
Der volle Inhalt der QuelleRivé, Karine. „Origine du carbone inorganique dissous dans les rivières des zones volcaniques : le point de vue des isotopes du carbone“. Paris 7, 2008. http://www.theses.fr/2008PA077222.
Der volle Inhalt der QuelleOn Earth, chemical weathering of silicate rocks is one of the mechanisms which consumes CO₂. All of these processes could be part of a negative feedback loop exerted on the Earth's climate, which would allow its regulation over geological time. Volcanic rocks have an important role since they are responsible for 30 pourcents of total CO₂ by weathering. The main challenge of this study is to identify the origin of CO₂ involved in the reactions of weathering of rocks of four active volcanic areas: the West Indies, Reunion, the Iceland and the Massif Central. In this aim, the delta13C of dissolved inorganic carbon (DIC) and riverine major ions were combined. In a first step, a reliable method of sampling and analysis of delta¹³C DIC has been developed. The analyse of nearly 200 samples from rivers, soil and solutions hydrothermal springs has highlighted that the magmatic CO₂ contributes significantly to the weathering of volcanic rocks, or even that it represents most of the CO₂ consumed by weathering in Iceland and Reunion, the other main reservoir of CO2 being biogenic CO₂. In addition, magmatic CO₂ appears to contribute to the weathering in different ways: either through hydrothermal contributions, or as diffuse magmatic CO₂. Both types of CO₂ would be associated with different schemes of weathering: soil type regime at low temperature, and the hydrothermal regime. The consequence of these observations is an overstatement of the rate of atmospheric CO₂ previously calculated by the mean of major ions in active zones. There seem to be a link between the proportion of CO₂ magmatic and rates of chemical weathering of rocks, which would indicate a control of weathering of active volcanic areas by magmatic CO₂. This underlines the need for measures of delta¹³CDic on a global scale, particularly in volcanic areas
Gillon, Marina. „Etude des modes d'acquisition de la signature isotopique en carbone des eaux souterraines et préservation du signal environnemental lors de la recharge des aquifères“. Paris 11, 2008. http://www.theses.fr/2008PA112038.
Der volle Inhalt der QuelleThe management of groundwater needs the estimation of the water residence time in aquifers, that can be done through the measurement of 14C radioactive decay of the Total Dissolved Inorganic Carbon (TDIC). This approach requires the knowledge of the TDIC 14C initial activity in recharge water. The groundwater mineralisation occurs in the Unsaturated Zone (UZ), where water interacts with CO2 and carbonates (if existing). We focus here on these interactions between both CO2, TDIC and carbonates. Two UZ have been investigated in France: the carbonate-free Fontainebleau sands and the carbonated Astian sands. Each site is equipped with a specific and experimental equipment to collect groundwater, UZ water, gas and solid matrix (organic matter and carbonate). The field-data are completed by a numeric approach in order to evaluate the different factors that define the CO2 isotopic composition at the bottom of the UZ. The 13C of CO2 depends on the mean 13C of produced CO2, the amount of produced CO2 and the diffusion coefficient of CO2. Subsurface seasonal variations of 13C disappear with depth. Before 1950, the 14C activity of CO2 can be assumed equal to atmospheric 14C level. After 1950, due to the atmospheric nuclear test, it depends on 14C activity of young organic matter and atmospheric CO2. The presence of carbonates leads to a 13C-enrichment of and a 14C-depletion of CO2 with depth, depending on the carbonate precipitation/dissolution flux, the amount of produced CO2 and the diffusion coefficient of CO2
Thomassot, Emilie. „Origine et formation des diamants dans le manteau supérieur terrestre : apport d'une systématique multi-isotopique (carbone, azote et soufre)“. Paris 7, 2006. http://www.theses.fr/2006PA077183.
Der volle Inhalt der QuelleIn order to better constraint the origin and the crystallization process of diamond in the Earth upper mantle, we have undertaken a coupled isotopic study of diamond and of their sulfide inclusions. Mass-independent sulfur isotope fractionations are preserved in sulfide inclusions in diamonds (SID) from the Kaapvaal craton (Botswana and South Africa). This specific isotopic signature, produced through photochemical reaction during the Archean, implies that sulfide inclusions in diamonds represent an Archean atmospheric sulfur component that was recycled into the Earth's mantle. However, geochemical characteristics of their host diamonds (δ¹³C, δ¹5N, N-content and its speciation) are largely homogeneous through the population, and close to the non-fractionated mantle-related values. This lack of recycled signature in the carbon diamond source allows us to conclude that diamonds and their inclusions are not necessarily syngenetic. Moreover, the specific geochemical characteristics of sulfide-bearing diamonds differs from silicate-bearing diamond signature. This last observation is unforeseen and discloses that sulfide-bearing diamonds belong to a specific diamond population. The present work, brings evidences in favor of the implication of a metasomatic agent (carbon bearing fluid) leading to diamond cristallization in mantle rocks
Lévy, Dan. „Minéralogie et composition isotopique des phases d’altération des premières roches du Système Solaire“. Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS206.
Der volle Inhalt der QuelleCalcium and aluminium-rich inclusions (CAIs) are the first solid objects formed in the solar system 4.568 Ga ago. We can estimate that they formed at a temperature higher than 1200 °C in very reducing conditions near the young Sun. In contrast, secondary phases found in CAIs suggest oxidizing and/or low temperature conditions. Most of these phases were interpreted as formed lately. However, a nebular origin of some secondary phases is still debated. The purpose of the thesis is to test if some secondary phases could have formed during CAI formation in the nebula using coupled different techniques. A compound CAI, named E101.1, from the CV3 reduced chondritic meteorite Efremovka was studied. This CAI is relevant for the study because it contains FeO-rich phases enclosed in diopside enclosed itself in the host CAI. These phases were characterized as Fe-åkermanite, kirschsteinite, fine-grained assemblage associated with wollastonite. The petrologic and textural study of these phases carried out during the thesis suggests that kirschsteinite and wollastonite formed in the nebula within an anorthite and diopside-rich precursors. Fe-åkermanite likely crystallized during the precursor incorporation into the partially melted host CAI. This is consistent with the first results of petrologic experiments that were initiated. After developping NanoSIMS imaging of D/H ratio on FIB (Focused Ion Beam) sections in weakly hydrated minerals, the δD of E101.1 minerals were measured. The lowest values ever measured in a meteoritic sample were found in anorhite with a δD of -817 ± 185 ‰ (2σ). This value is consistent with a formation near the young Sun. The fine-grained assemblage has high δD values up to 1250 ± 516 ‰ (2σ). Kirschsteinite has chondritic δD value: 163 ± 201 ‰ (2σ). The high values were attributed to evaporation during the xenolith capture in agreement with petrologic obervations which implies that kirschsteinite and wollastonite formed in the nebula in a reservoir with a chondritic H isotopic composition. This means that the D/H ratio of the nebula water passed from a solar value to a nearly terrestrial value in several hundred thousand years maximum. These complementary approaches hence showed the presence of nebular alteration phases in a CAI and that a non-predicted thermodynamical oxidizing event occured in the nebula
Marin, Carbonne Johanna. „Composition isotopique de l'oxygène et du silicium des cherts Précambriens : implications Paléo-environnementales“. Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL086N/document.
Der volle Inhalt der QuelleCherts, which are siliceous rocks, are considered as possible proxies of paleo-environmental conditions of the Early Earth. These rocks contain various forms of quartz, microquartz being the predominant one. The study of oxygen and silicon isotopic composition in the various forms of silica in cherts of different ages, from 3,5 Ga to 1,9 Ga, allowed to better understand the origin and the formation of these rocks and allowed to try to reconstruct paleo-temperatures for Precambrian seawater. Isotopic measurements were obtained with the ims 1270 multicollector ion microprobe with a precision better than 0,2 ‰ for [delta]18O and of ˜ 0,3 ‰ for [delta]30Si. These analyses were combined with the measurement of traces elements concentrations (B, Na, Mg, Al, K, Ca, Ti, Fe) with the ims 3f ion microprobe, with a petrographical study of microquartz and with the study of fluid inclusions in quartz veins. The major result is the existence at a micrometer scale of a large range of variations for [delta]18O (between 1 ‰ to 14?‰) and [delta]30Si (between 2‰ to 5‰). In the Gunflint cherts, the range of [delta]18O variation has been interpreted as due to diagenesis and has been used to reconstruct oceanic paleo-temperatures. The calculated temperatures range from +37°C to +52°C, suggesting an hot ocean during the Precambrian era if Gunflint cherts are representative of global environmental conditions. The [delta]30Si variations associated with that of trace elements concentrations allow to constrain the various origins of these cherts. The effect of fluid circulations on the isotopic compositions has been characterized by [delta]18O and [delta]30Si analyses and by fluid inclusions study. It is shown that in some cases the [delta]18O value of microquartz can be totally re-equilibrated with the hydrothermal or metamorphic fluids. The approach developed in this thesis will be decisive in future studies of Archean cherts for paleotemperature reconstructions
Rhino, Kévins. „Caractérisation, quantification et modélisation des processus de transfert et des interactions CO₂-eau-roche en milieu poreux non saturé en contexte de forage lors d'un stockage géologique“. Thesis, Bordeaux 3, 2017. http://www.theses.fr/2017BOR30040/document.
Der volle Inhalt der QuelleCarbon storage is one of the most encouraging methods to decrease CO₂ concentration into the atmosphere. Carbon storage provides the longevity and the capacity needed to decrease CO₂ emissions toward the atmosphere. When dealing with storage on an industrial scale, carbonated reservoirs can be among the most suitable storage sites. However, these high depth injections are subject to leakage risks from the geologic trap itself or from the framework created by the establishment of the site. Two main types of leakage exist: brutal and diffusive leakage. In both cases, they are likely to endanger the environment and the population. Therefore, it is essential to develop tools that are able to anticipate any types of CO₂ leakage. Furthermore, it is also necessary to understand the reactive transport mechanism that take place when the leakage arrives in the shallow subsurface (vadose zone)and to see how the leakage can be buffered. This work deals with the characterization, the quantification and the modelling of transfer processes and CO₂-H₂O-CaCO₃ interactions into the vadose zone in a context of a leakage from a drilling well. This issue was first dealt through field experiment on the site of Saint Emilion. Then, the CO₂-H₂O-CaCO₃ interactions were studied through an experimental approach in laboratory. Two leakage experiments were performed on the site: a diffusive leakage and an ultra-diffusive leakage. They were performed as a sequel of former experiments carried on the pilot site. A comparison of all the leakage experiments revealed the necessity to use noble gases as precursor of the CO₂ arrival at the surface. Depending of the type of the leakage, helium can be a temporal precursor while krypton can anticipate the spread of the CO₂ gas plume. The higher the injection pressure, the more the gas migrates through advective flux. Moreover, a high injection pressure favors the existence of preferential paths in the vadose zone. The use of helium and carbon isotopes makes it possible to reveal the presence of a local aqueous phase within the porous media and to identify the origin of CO₂. The core scale experiments lead to the estimation of the buffering power of Oligocene limestone according to the rock facies. The permeability and the porosity influence the dissolution of the limestone. The reactivity of carbonates during a leakage depends on the pH of the aqueous phase, the flow rate that goes through the porous media, the water saturation and petrophysical characteristics of the carbonates
Brunet, Frédéric. „VARIATIONS DE LA SIGNATURE ISOTOPIQUE δ13C DU CARBONE INORGANIQUE DISSOUS DANS LES RIVIÈRES ET LES FLEUVES“. Phd thesis, Université Paul Sabatier - Toulouse III, 2004. http://tel.archives-ouvertes.fr/tel-00184081.
Der volle Inhalt der QuelleLebeau, Oanez. „Enregistrement isotopique des cycles biogéochimiques du carbone et de l'azote dans les sédiments du lac Pavin“. Paris 7, 2014. http://www.theses.fr/2014PA077108.
Der volle Inhalt der QuelleOver geological timescale, the Earth's oceans were affected by several periods of total or partial anoxia. Causes and consequences of the ocean oxygenation can potentially be better understood from past C and N cycles. Studies on modern analogues are essential for interpreting the biogeochemical signal recorded in ancient sediments and to determine if the primary C and N isotope signatures are preserved or modified in this type of environment. Lake Pavin (Massif Central, France) is permanently stratified with anoxic Fe-rich deep waters overlain by oxic shallow waters, and can be regarded as an analogue for the oceans during periods of redox stratification with ferruginous deep waters. In the present work, we determined the C and N isotope compositions of 6 sediment cores in Lake Pavin (3 in the oxic zone and 3 in the anoxic zone), and of sediment traps set up at different depths in the water column and collected regularly over 15 months. δ¹⁵ values of primary biomass, coupled with concentrations and δ¹⁵ N of dissolved nitrogen (nitrate and ammonium), suggest that organic nitrogen derives mainly from N2-fixation in surface waters. δ¹³ C values show a bimodal distribution, reflecting seasonal changes in dissolved CO2 isotope composition. Diagenetic modifications of C and N concentrations and isotope compositions have been evaluated for particles sinking in the water column, water-sediment interface, and in the sedimentary pile. In all cases, diagenesis induces a decrease in C and N concentrations and an increase in C/N ratio, with larger modifications under oxic than anoxic conditions. The δ¹³ C and δ¹⁵ N values are well preserved in the anoxic zone, but are strongly modified in the oxic zone. Potential variations related to eutrophisation and/or a contribution of detrital materials are also presented
Aguilera, Rodrigo. „Différenciation entre testostérone endogène et testostérone exogène par analyse isotopique du carbone : application au contrôle antidopage“. Lyon 1, 1996. http://www.theses.fr/1996LYO10021.
Der volle Inhalt der QuelleVicars, William. „Transfert de l'anomalie isotopique portée par l'ozone dans la troposphère : vers une interprétation quantitative de la composition isotopique en oxygène du nitrate atmosphérique“. Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-00856960.
Der volle Inhalt der QuelleDelaygue, Gilles. „Relations entre surface océanique et composition isotopique des précipitations antarctiques : simulation pour différents climats“. Phd thesis, Aix-Marseille 3, 2000. http://tel.archives-ouvertes.fr/tel-00002821.
Der volle Inhalt der QuelleDreyfus, Gabrielle Boissier. „La composition isotopique de l'air piégé dans la glace : interprétation climatique et outil chronologique“. Paris 6, 2008. http://www.theses.fr/2008PA066580.
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