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Dissertations / Theses on the topic 'Isotopic tracer'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Winkler, Renato. "Triple-oxygen isotopic composition of meteoric waters : 17 O-excess a new tracer of the hydrological cycle." Versailles-St Quentin en Yvelines, 2012. http://www.theses.fr/2012VERS0040.

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Les enregistrements des carottes glaciaires permettent de renseigner les mécanismes climatiques des derniers 800 000 ans et ainsi d'améliorer les projections climatiques pour le futur. Cette thèse est basée sur l'utilisation de la composition isotopique de l'eau dans les carottes de glace pour l'étude des mécanismes du cycle hydrologique global. Nous avons analysé la composition isotopique triple de l'eau (17Oexcess) comme traceur de l'humidité relative lors de l'évaporation au-dessus de l'océan. Les résultats principaux sont les suivants : des études de calibration au laboratoire et sur le te

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2

Warren, Clemence P. "Isotopic Tracer Reveals Depth-Specific Water Use Patterns Between Two Adjacent Native and Non-native Plant Communities." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/1084.

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Non-native plants have invaded over 100 millions of acres of western arid land in the US and dramatically altered nutrient cycling rates. Changes in water cycling caused by invasive species are of particular interest because primary production in the Western US is typically limited by water availability and aquifer recharge reflects plant demand. Large-scale invasions can, therefore, be expected to cause large-scale changes in hydrological cycles, but until recently, there have been considerable limitations in the ability to measure the timing, location, and extent of water use. Here we inject

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3

Al-Qahtani, Mohammed H. S. "Development of new and improved labelling procedures for introducing isotopic hydrogen and carbon-11 into organic compounds." Thesis, University of Surrey, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300367.

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4

Beynon, J. "Mineral reactions and isotopic tracer transport in the Troodos ophiolite as analogues of hydrothermal systems at mid-ocean ridges." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.596622.

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The structure and evolution of mid-ocean ridge hydrothermal systems and the magnitude of crustal alteration associated with different temperature fluid fluxes are poorly understood. This project has used strontium and oxygen isotopes together with metamorphic assemblages to investigate fluid flow geometry, fluid evolution and fluid-rock interaction during hydrothermal circulation in the Troodos Alteration Zone, the mesostasis has been altered to saponite but coarse clinopyroxene and plagioclase phenocrysts are unaltered. Homogeneous whole rock 90 Ma <SUP>87</SUP>Sr/<SUP>86</SUP>Sr profiles fro

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Plamboeck, Agneta H. "Root activity in Scots pine dominated stands assessed by isotopic methods /." Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5646-0.pdf.

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6

Tolu, Julie. "Spéciation et mobilité du sélénium présent dans les sols à l’état de traces : contribution aux prévisions à long terme." Thesis, Pau, 2012. http://www.theses.fr/2012PAUU3002/document.

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Les analyses de sûreté du stockage des déchets radioactifs HAVL nécessite une évaluation à long terme (≈ 10 000 ans) des risques, pour l’homme et l’environnement, associés à une contamination des sols par le sélénium. Une méthodologie a donc été développée pour déterminer les espèces séléniées (spéciation) présentes à l’état de traces dans les sols (μg kg-1 ; contexte radiologique) et estimer, leur capacité à être lessivées et leurs phases de rétention. Combinée à l’utilisation du traceur 77Se(IV), l’existence de processus lents impliqués dans la rétention et la transformation chimique de Se d

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7

Grant, Steven Lloyd. "Geochemical, radiogenic tracer isotopic, and U-Pb geochronological studies of Yukon Tanana terrane rocks from the Money klippe, southeastern Yukon, Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq22600.pdf.

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8

Gudmundsson, Kjartan. "Alternative methods for analysing moisture transport in buildings : Utilisation of tracer gas and natural stable isotopes." Doctoral thesis, KTH, Byggvetenskap, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3509.

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New methods, based on tracer gas measurements and isotopicanalysis can be used to evaluate the moisture properties ofbuilding materials and provide the means for forensic analysisof the origins and history of excessive water in buildings, theimmediate practical consequences of which will be the abilityto improve the moisture performance of constructions. It is shown, in theory and through measurements how thewater vapour permeability of porous building materials can witha good degree of accuracy be estimated with tracer gasmeasurements that provide an efficient alternative to the cupmethod. Co

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9

Casado, Mathieu. "Water stable isotopic composition on the East Antarctic Plateau : measurements at low temperature of the vapour composition, utilisation as an atmospheric tracer and implication for paleoclimate studies." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV058/document.

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Les carottes de glace permettent de reconstruire le climat du passé, à partir entre autre de la composition isotopique de l’eau (δ18O, δ17O et δD). Sur le plateau Est Antarctique, les températures très froides et les faibles accumulations permettent de remonter le plus loin dans le passé (jusqu’à 800 000 ans) mais compliquent l’interprétation du signal isotopique. Premièrement, les reconstructions des variations de température dans les carottes de glace à partir des isotopes de l’eau se basent sur des modèles pour décrire l'évolution de la composition isotopique de la vapeur et de la phase con

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10

Robson, P. "Structural studies of phosphates and molybdophosphates formed in nitric acid : Vibrational spectroscopic, isotopic-tracer and plutonium/americium absorption studies on zirconium phosphate and ammonium/caesium/rubidium molybdophosphates formed in nitric ac." Thesis, University of Bradford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379904.

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11

Lunel, Tim. "Trace metal concentrations and isotopes as tracers of oceanic processes." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277899.

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12

Nilsson, Lino. "Nitrogen transformations at the Kiruna mine : The use of stable nitrogen isotopes to trace nitrogen-transforming processes." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-209419.

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Release of different nitrogen compounds can cause eutrophication in lakes and rivers whichcan lead to oxygen-free environments in bottom water and in the sediment and can in turnlead to fish-deaths. Ammonium can be toxic to biota and nitrate can in high concentrationeven be toxic to humans. WHO has released a limit for nitrate concentration in drinking waterof 10mg/l. The LKAB mine in Kiruna is the largest underground iron mine in the world and isprospecting, mining and refining iron ore, with an annual production of around 28 milliontons. Release of different nitrogen compounds as a result of

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13

Laporte, Marie-Aline. "Contribution à la modélisation de l’absorption du cadmium par les racines du tournesol (Helianthus annuus L.) en relation avec l’architecture racinaire." Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR15214/document.

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Le cadmium (Cd) est naturellement présent dans les sols qui sont aussi enrichis par l'activité humaine. Le Cd contamine les produits végétaux alimentaires car il est absorbé par les racines des plantes. Elément toxique pour les organismes vivants, les concentrations dans les produits consommés sont soumises aux règlementations pour l’alimentation humaine et animale. Il est donc nécessaire de comprendre le transfert sol-organe consommé du Cd, spécialement pour le tournesol (Helianthus annuus L.), notre plante modèle, pouvant accumuler plus de Cd que d’autre plantes cultivées. Ce travail a testé

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Ulusoy, Ulvi. "Determination of uptake of essential trace elements using stable isotopic tracers and rare earth markers." Thesis, University of Glasgow, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321044.

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15

Hsieh, Yu-Te. "Using uranium- and thorium-series isotopes as tracers for trace-metal inputs to the oceans." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:9574b34a-3932-4a16-a823-17028ef889f2.

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This thesis explores the use of U-Th series isotopes as tracers to study ocean mixing and chemical inputs to the open ocean from atmospheric dust, rivers, continental shelves and ocean sediments. The use of Th isotopes as an improved tracer of dust input has been tested by measuring <sup>232</sup>Th and <sup>230</sup>Th concentrations of upper-ocean seawater at six stations along a meridional Atlantic section that spans the Saharan dust plume. The results of <sup>232</sup>Th-derived dust fluxes show good agreements with dust model depositions, and suggest that thorium may be a more accurate tr

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Di, Hong J. "Application of isotopic dilution methods to the study of the dissolution of phosphate fertilisers of differing solubility in the soil." Lincoln University, 1991. http://hdl.handle.net/10182/1792.

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An injection technique, in which undisturbed soil cores are labelled with ³²P to study dissolution of phosphate fertilisers in the soil, was evaluated in field and glasshouse trials. When ³²P was injected between 0-150 mm depths of the undisturbed soil columns and fertilisers applied at the surface, the amounts of fertiliser P dissolved, as measured by the increases in the exchangeable P pools, were overestimated. Three possible reasons were suggested: (i) the interaction between surface-applied fertiliser, ³²P injected through the whole soil column, and the vertical decline in root density, (

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17

Guillou, Sebastien. "Etude du comportement d'un alliage chromino-formeur comme matériau d'interconnecteur pour l'Electrolyse à Haute Température." Thesis, Dijon, 2011. http://www.theses.fr/2011DIJOS082/document.

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Dans les systèmes d’Electrolyse Haute Température (EHT), le matériau choisi comme interconnecteur doit avoir une bonne résistance à la corrosion sous air et sous mélange H2/H2O à 800 °C, et maintenir une bonne conductivité sur de longues durées. Dans ce cadre, l’objectif de ce travail était, d’une part, d’évaluer un alliage ferritique commercial (l’alliage K41X) comme matériau d’interconnecteur pour l’application EHT. Dans ce but, ont été mis en place des essais d’oxydation en four et en thermoblance pour accéder aux cinétiques d’oxydation, et des mesures de résistivité pour évaluer le paramèt

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Ayache, Mohamed. "Modélisation d’éléments traces (T, 3He, Nd, 14C) en mer Méditerranée pour l’étude des cycles biogéochimiques et de la circulation océanique." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV138/document.

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Dans cette thèse nous avons simulé la distribution d’éléments traces en Méditerranée, dans le but de mieux contraindre la circulation thermohaline et les cycles biogéochimiques. Pour cela, nous avons utilisé le modèle dynamique à haute résolution NEMO-MED12 couplé avec le modèle de biogéochimie marine PISCES.La Méditerranée offre un cadre particulièrement attrayant pour l’étude des traceurs géochimiques. Il s’agit d’une mer semi-fermée, ce qui permet de mieux contraindre les différentes sources et puits des éléments (poussières atmosphériques, fleuves …). Plus particulièrement, nous avons modé

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19

Delavau, Carly J. "Development of precipitation δ18O isoscapes for Canada and application within a tracer-aided hydrological model". Taylor and Francis, American Geophysical Union, 2015. http://hdl.handle.net/1993/31946.

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Delineating spatial patterns of precipitation isotopes (“isoscapes”) is important for studies including the hydrology of terrestrial systems, present and past interpretations of climate, and tracer-aided hydrological modelling, among others. However, the extent to which precipitation isoscapes can be predicted across Canada has not been fully articulated. This thesis combines isotopes in precipitation (δ18Oppt) observations from two regional and one global network to create long term and time series precipitation isoscapes for Canada and the northern United States. Multi-linear regressions of

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Ferreira, Araujo Daniel. "Investigations into isotope biogeochemistry of Zn in coastal areas and mangroves." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30368/document.

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Les zones côtières du monde entier sont sous fort pression de contamination anthropique comme conséquence de la concentration de la plupart de la population mondiale et des activités économiques le long des côtes et des estuaires. La menace de contaminant sur les écosystèmes rend primordial le développement d'outils capable de détecter les modifications biogéochimiques en vue d'aider dans la prévention, la gestion, et la prédiction de risques dans les études environnementales. Dans ce but, cette thèse étudie la biogéochimie des isotopes du Zinc (Zn) en vue de développer un outil capable de tra

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21

Hagby, Johannes. "Contributions of Event Water to Streamflow in an Agricultural Catchment." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-353780.

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In agricultural catchments, hydrological processes play an important role in the export of nutrients. Water that enters a catchment during a rain event (event water) can have different flow paths and residence times. These affect the transport and biogeochemical transformation of nutrients until the water discharges at the outlet where catchments are usually monitored.This work focused on the contributions of event water and pre-event water (water that was already stored in the catchment before a rainfall event) to the stream. The work is necessary for further studies to develop an understandi

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Kipp, Lauren Elizabeth. "Radium isotopes as tracers of boundary inputs of nutrients and trace elements to the coastal and open ocean." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/119990.

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Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2018.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references.<br>Nutrients and trace metals are vital for supporting life in the ocean, but the boundary processes that control the distributions of these elements are poorly constrained. Radium isotopes are well suited to studying inputs of elements from ocean margins because they are produced in

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23

Milot, Jean. "Utilisation des isotopes du fer pour le traçage des métaux anciens : développement méthodologique et applications archéologiques." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30367/document.

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L'objectif de ce travail de thèse a été de développer l'utilisation des isotopes du fer pour le traçage des métaux anciens, principalement ferreux. Notre approche méthodologique s'est articulée autour de trois axes majeurs. Le premier axe a consisté à étudier l'influence potentielle des processus métallurgiques sur la composition isotopique du fer des métaux produits. Pour cela, nous avons mesuré la composition isotopique du fer d'échantillons issus d'expérimentations de réduction de minerai de fer en bas fourneau, réalisées sur un site sidérurgique majeur de la période romaine (la Montagne No

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Einloth, Sharon L. "Intrinsic Isotopic Tracers as Independent Evaluators for China Lake Basin, CA." Thesis, The University of Arizona, 2000. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0204_sip1_w.pdf&type=application/pdf.

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Scott, Mari. "Lead isotopes as a palaeodietary tracer in southwestern South Africa." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29428.

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This thesis evaluates the utility of lead (Pb) isotopes, in combination with strontium (Sr) isotopes, as a geochemical tracer for studying the palaeodiets and palaeo-landscape usage in southwestern South Africa. Isotopes of light elements, carbon (C), nitrogen (N), oxygen (O), and sulphur (S), are widely used as (palaeo) environmental tracers, but do not yield information on the geological substrates on which individuals have lived. Sr isotopes in bones and teeth are useful in distinguishing between areas of distinct bedrock geology, however, the efficiency of Sr is limited at near-coastal are

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Boehme-Terrana, Linae Marie. "Trace metals and stable isotopes as tracers of life history and trophic connections in estuarine-dependent fish from Tampa Bay, Florida." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002241.

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Quast, Konrad William. "Boron isotopes as intrinsic and artificial hydrologic tracers." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/290013.

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This work investigates the conservative behavior of boron isotopes and their potential use as an artificial hydrologic tracer. The usefulness of boron isotopes as intrinsic hydrologic tracers and the assumption that boron isotopes are conservative in many natural environments led to the hypothesis that they can be easily adapted as artificial hydrologic tracers. The results are demonstrated in three field studies and a laboratory study carried out under the Soil Aquifer Treatment project. Non-conservative behavior of intrinsic boron isotope ratios was found in vadose zone and groundwater sampl

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Moore, Mary. "Stable Water Isotopes as Tracers in Global Precipitation." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493530.

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Stable water isotopes (H2O, H18O, and HDO) are incorporated into the microphysics schemes of two different atmospheric models. This thesis describes the use of these molecules as tracers in precipitation budgets to assess the processes controlling the isotopic signatures of precipitation in the tropics and orographic snow in the mid-latitudes. The idealized simulations of seasonal precipitation budgets in the tropics determine that increased vapor convergence during intense precipitation is most important for setting the isotopic composition of the convective precipitation. The isotopic signa

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Bonnand, Pierre. "Potential of chromium isotopes as a tracer of past ocean oxygenation." Thesis, Open University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543870.

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Levels of atmospheric oxygen (02 ) hav(' increaseo from <2o/r:. of the present atlnospheric level (PAL) to values similar to the PAL during the N('oproterozoic. This is likely to have resulteo in significant changes in redox conditions in thp ocpans. The aim of this stud.v is to provide new constraints on redox conditions in shallow seawater during the Neoproterozoic by analysis of the rare earth element (REE) concentration and chromium (Cr) isotopic composition of marine carbonatps. To this end, a new method for J 53Cr analysis in low concentration samples has been developed. In addition, the

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Yu, Huimin. "Li, Hf and Os Isotope Systematics of Azores Basalts and A New Microwave Digestion Method for Os Isotopic Analysis." Miami University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=miami1322847998.

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Sivry, Yann. "Utilisation des isotopes stables de Cd, Zn, Cu, Ni et Pb pour quantifier le compartiment échangeable des éléments trace métalliques et de delta66Zn pour tracer les pollutions polymétalliques." Toulouse 3, 2008. http://thesesups.ups-tlse.fr/471/.

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Une technique de " spikage ", ou dilution d'isotopes stables multi-élémentaire, a été est développée afin de quantifier et caractériser simultanément les compartiments échangeables de Cd, Zn, Cu, Ni et Pb dans des sols contaminés. Cette technique a étéest ici validée par comparaison avec les résultats de spikage d'isotopes radioactifs de Cd, ainsi que ceux d'extractions chimiques. Par ailleurs, une étude intégrée des signatures isotopiques du Zn (d66Zn) dans plusieurs compartiments d'écosystèmes contaminés (sites métallurgiques de Viviez-Decazeville, S. -O. France et de Kempen, N. -E. Belgique

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Colgan, Gary A. "Estimating surface/ground-water mixing using stable environmental isotopes." Thesis, The University of Arizona, 1989. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0042_m_sip1_w.pdf&type=application/pdf.

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Antoniewicz, Maciek Robert. "Comprehensive analysis of metabolic pathways through the combined use of multiple isotopic tracers." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37457.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2006.<br>Includes bibliographical references (p. 287-294).<br>Metabolic Flux Analysis (MFA) has emerged as a tool of great significance for metabolic engineering and the analysis of human metabolic diseases. An important limitation of MFA, as carried out via stable isotope labeling and GC/MS measurements, is the large number of isotopomer equations that need to be solved. This restriction reduces the ability of MFA to fully utilize the power of multiple isotopic tracers in elucidating the physiology of compl

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Sutton, David G. M. "Stable isotope tracer studies for the measurement of equine gastrointestinal motility." Thesis, University of Glasgow, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422249.

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Astier-Simon, Sophie. "Contribution de la géochimie à l'étude des matériaux. Application de traceurs (éléments majeurs, traces et isotopes du strontium) à l'étude de la protection et de la durabilité des pierres calcaires et des bétons." Montpellier 2, 1998. http://www.theses.fr/1998MON20107.

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L'eau occupe un role preponderant dans les phenomenes d'alteration des materiaux. Nous avons effectue une etude comparative de materiaux non traites ou traites par un produit mineralisateur protecteur afin de quantifier l'effet de ce produit, et d'evaluer l'accroissement de durabilite lie a sa presence. L'etude geochimique est fondee sur la mesure des concentrations d'elements majeurs et traces dans les lessivats et nous permet de mettre en evidence le role de barriere joue par le produit. Les mesures de composition isotopique du strontium nous ont permis de calculer un coefficient de retentio

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Campbell, Darcy Jo. "Fractionation of stable chlorine isotopes during transport through semipermeable membranes." Thesis, The University of Arizona, 1985. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0002_m_sip1_w.pdf&type=application/pdf.

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Gall, Louise. "Development and application of nickel stable isotopes as a new geochemical tracer." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:ebe3c3e1-0b1b-49ed-b64a-016c8d76f220.

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In this thesis, I have developed a new methodology for the accurate determination of mass-dependent variations in nickel (Ni) isotope compositions. Nickel is initially separated in a three-column ion-exchange procedure, and the purified solutions are analysed by multi-collector inductively coupled plasma mass spectrometry (MCICPMS) using a double-spike technique. Using this methodology, I have measured the first Ni isotope ratios for a wide variety of natural geological samples. Significant Ni isotope variations were observed, with an overall spread in delta 60Ni-values of -0.9 to 2.5 permil.

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Featherstone, Amy Marie. "Construction of long annually-resolved shell-based chronologies using Glycymeris glycymeris (Bivalvia ; Glycymerididae) from the Bay of Brest, France." Thesis, Brest, 2017. http://www.theses.fr/2017BRES0052/document.

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Ce doctorat repose sur l'utilisation de Glycymeris glycymeris, un bivalve de la famille des Glycymerididae, pour reconstruire la variabilité environnementale en rade de Brest (France). Il vise à comparer des données géochimiques archivées dans ces coquilles avec diverses variables biologiques et écologiques. Les objectifs sont d'identifier de potentiels proxys et d'étendre notre connaissance de la variabilité environnementale avant les premières mesures instrumentales.Au total, 38 spécimens (vivants ou morts) ont été utilisés pour construire une chronologie s'étendant de 1891 à 2014.Les indice

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Rosner, Martin Siegfried. "Boron as a tracer for material transfer in subduction zones." Phd thesis, [S.l. : s.n.], 2003. http://pub.ub.uni-potsdam.de/2003/0030/rosner.pdf.

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Lopez, Morgan. "Estimation des émissions de gaz à effet de serre à différentes échelles en France à l’aide d’observations de haute précision." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112284/document.

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L’objectif de ma thèse est de conduire et d’utiliser les observations de haute précision de gaz à effet de serre pour estimer les émissions de ces gaz à différentes échelles en France, du locale au régionale. Le réseau français de mesure de gaz à effet de serre, géré par l’équipe RAMCES, est constitué de trois observatoires équipés de systèmes de mesure par chromatographie en phase gazeuse. Ces chromatographes en phase gazeuse sont situés à Gif-sur-Yvette, Trainou (forêt d’Orléans) et au sommet du Puy-de-Dôme. Ils ont été optimisés pour la mesure continue et de haute précision des principaux g

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Pallavicini, Nicola. "Method development for isotope analysis of trace and ultra-trace elements in environmental matrices." Doctoral thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-59705.

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The increasing load of toxic elements entering the ecosystems, as a consequence of anthropogenic processes, has grown public awareness in the last decades, resulting in a great number of studies focusing on pollution sources, transport, distribution, interactions with living organisms and remediation. Physical/chemical processes that drive the uptake, assimilation, compartmentation and translocation of heavy metals in biota has received a great deal of attention recently, since elemental concentrations and isotopic composition in biological matrices can be used as probes of both natural and a

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Cheng, Zhongqi. "Refinement of isotopic analysis techniques for trace Pb and Sr and their selected applications /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486399160104707.

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Hale, Colin Andrus. "Strontium Isotopes-A Tracer for Dust and Flow Processes in an Alpine Catchment." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7459.

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Stream chemistry changes in response to snowmelt, but does not typically reflect thechemistry of the snowpack. This suggests that flow processes between snowmelt and streamsystem, such as interactions with the soil and bedrock, have an important control on waterchemistry and highlight the complex flow pathways from the snowpack to stream. To investigateflow processes in the upper Provo River watershed, northern Utah, we sampled three sites on theriver ~20 times per year during 2016 and 2017. The sites, from highest elevations to lowest wereSoapstone, Woodland, and Hailstone, corresponding to l

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Ballentine, Christopher John. "He, Ne, and Ar isotopes as tracers in crustal fluids." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387053.

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NAKAHIRA, SILVIO. "Utilizacao do Au-198 com marcacao superficial no estudo do transporte solido por arraste de fundo em canal natural de grande porte." reponame:Repositório Institucional do IPEN, 1987. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9890.

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Made available in DSpace on 2014-10-09T12:32:30Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T14:10:07Z (GMT). No. of bitstreams: 1 12894.pdf: 3496583 bytes, checksum: 5149c2b62809152eac0978234cafe18d (MD5)<br>Tese (Doutoramento)<br>IPEN/T<br>Escola Politecnica, Universidade de Sao Paulo - POLI/USP

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Anam, Onditi Ouma. "Gas diffusion-flow injection interfaces for mass spectrometric and electrochemical detectors." Thesis, Loughborough University, 1996. https://dspace.lboro.ac.uk/2134/28323.

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Isotope tracer techniques are widely used in biological, agricultural, chemical and medical research. The use of stable isotopes is not complicated by health hazards, dangers of radiation or time limit for experiments as is the case for radioactive isotopes. However, the analytical methods available for the determination of stable isotopes are much less sensitive, considerably more complicated and time consuming than those for radioactive isotopes. Such methods usually require the use of a mass spectrometer and most employ the combustion technique (Dumas method) for sample presentation. Specia

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Sivry, Yann. "Utilisation des isotopes stables de Cd, Zn, Cu, Ni et Pb pour quantifier le compartiment échangeable des éléments trace métalliques et de δ66Zn pour tracer les contaminations polymétalliques". Phd thesis, Université Paul Sabatier - Toulouse III, 2008. http://tel.archives-ouvertes.fr/tel-00375351.

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Une technique de « spikage », ou dilution d'isotopes stables multi-élémentaire, a été développée afin de quantifier et caractériser simultanément les compartiments échangeables de Cd, Zn, Cu, Ni et Pb dans des sols contaminés. Cette technique a été ici validée par comparaison avec les résultats de spikage d'isotopes radioactifs de Cd, ainsi que ceux d'extractions chimiques. Par ailleurs, une étude intégrée des signatures isotopiques du Zn (δ66Zn) dans plusieurs compartiments d'écosystèmes contaminés (sites métallurgiques de Viviez-Decazeville, S.-O. France et de Kempen, N.-E. Belgique) permet

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Day, Christopher Charles. "Trace-metals and isotopes in carbonates : understanding past climate records." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.555370.

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An increasing number of studies report stable-isotope and trace-element records in speleothems. This variation is controlled by diverse environmental variables including the climatically important variables, temperature and rainfall. There is, however, a paucity of laboratory studies attempting to understand the influence of these environmental controls on stalagmite geochemistry. Quantitative data from such studies would dramatically improve our ability to reconstruct palaeoclimate from stalagmites. This study produces a new calcite growth setup, which closely mimics natural processes (e.g. p

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Aravindhan, Karpagam Jucker Beat M. DiNardo N. John. "Assessing the effects of LXR agonists in cholesterol handling: stable isotope tracer studies /." Philadelphia, Pa. : Drexel University, 2005. http://dspace.library.drexel.edu/handle/1860/613.

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Pérez, Moreno Rodrigo. "Stable isotope and anthropogenic tracer signature of waters in an andean geothermal system." Tesis, Universidad de Chile, 2019. http://repositorio.uchile.cl/handle/2250/170853.

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Tesis para optar al grado de Magíster en Ciencias, Mención Geología<br>El presente trabajo se centra en el uso de isótopos estables y trazadores antropogénicos para investigar el origen, los tiempos de residencia y la evolución de las aguas termales en el Complejo Volcánico Lonquimay-Tolhuaca, ubicado en la parte central de la Zona Volcánica Sur. Veinte muestras de agua subterránea, surgiendo en un amplio rango de temperaturas (8-96°C), son analizadas para determinar su composición química, incluyendo elementos mayores, razones isotópicas (δ2H, δ18O, δ13CTDIC) y la concentración de clorofluoro

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