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MENGHI, MARTA. "Containers off the track, abitare la mobilità tra logistica ed emergenza." Doctoral thesis, Università degli studi di Genova, 2020. http://hdl.handle.net/11567/1009920.
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After going through the milestones that have marked the logistical transformation and the rise of containerisation, the thesis focuses on two different but assimilable emergency contexts for the use of the same matrix and rationality of government. The Roja Camp of Ventimiglia on the Italian-French border, an area dedicated to the containment of transit and asylum seekers managed since 2016 by the Italian Red Cross and the container village of Tolentino in Marche region, strongly affected by the earthquake of 2016/2017, responsible for the reception of displaced persons. The attention is devoted to the dimension of living and the administrative management practices, tracing the violence hidden in a circulatory government that extracts value from mobility of subjects. Two spaces "not completely opened" and "not completely enclosed", expression of a governmentality that exploits the absence of a specific normative provision. Two places where the container becomes the setting of a process of othering, in the time of the emergency.
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Cayèré, Cécile. "Modélisation de trajectoires sémantiques et calcul de similarité intégrés à un ETL." Electronic Thesis or Diss., La Rochelle, 2022. http://www.theses.fr/2022LAROS042.
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Cette dernière décennie, nous avons pu constater une montée en popularité des applications mobiles basées sur la localisation des téléphones. Ces applications collectent des traces de mobilité qui retracent le déplacement des utilisateurs au cours du temps. Dans le projet régional DA3T, nous faisons l’hypothèse que l’analyse des traces de mobilité de touristes peut aider les aménageurs dans la gestion et la valorisation des territoires touristiques. L’objectif est de concevoir des méthodes et des outils d’aide à l’analyse de ces traces. Cette thèse s’intéresse au traitement des traces de mobilité et propose une plateforme modulaire permettant de créer et d’exécuter des chaînes de traitement sur ces données. Au fil des modules d’une chaîne de traitement, la trace de mobilité brute évolue en trajectoires sémantiques. Les contributions de cette thèse sont : (i) un modèle de trajectoire sémantique multi-niveau et multi-aspect et (ii) deux mesures calculant la similarité entre deux trajectoires sémantiques s’intéressant aux dimensions spatiales, temporelle et thématique. Notre modèle (i) est utilisé comme modèle de transition entre les modules d’une chaîne de traitement. Nous l’avons mis à l’épreuve en instanciant des trajectoires sémantiques issues de différents jeux de données de domaines variés. Nos deux mesures (ii) sont intégrées à notre plateforme comme modules de traitement. Ces mesures présentent des originalités : l’une est la combinaison de sous-mesures, chacune permettant d’évaluer la similarité des trajectoires sur les trois dimensions et selon trois niveaux de granularité différents, l’autre est la combinaison de deux sous-mesures bidimensionnelles centrées autour d’une dimension en particulier. Nous avons évalué nos deux mesures en les comparant à d’autres mesures et à l’avis de géographes<br>Over the last decade, we have seen a rise in popularity of mobile applications based on phone location. These applications collect mobility tracks which describe the movement of users overtime. In the DA3T regional project, we hypothesise that the analysis of tourists’ mobility tracks can help planners in the management and enhancement of tourist areas. The objective is to design methods and tools to help analyse these tracks. This thesis focuses on the processing of mobility tracks and proposes a modular platform for creating and executing processing chains on these data. Throughout the modules of a processing chain, the raw mobility track evolves into semantic trajectories. The contributions of this thesis are: (i) a multi-level and multi-aspect semantic trajectory model and (ii) two measures that compute the similarity between two semantic trajectories along spatial, temporal and thematic dimensions. Our model (i) is used as a transition model between modules of a processing chain. We tested it by instantiating semantic trajectories from different datasets of various domains. Our two measures (ii) are integrated in our platform as processing modules. These measures present originalities: one is the combination of sub-measures, each allowing to evaluate the similarity of trajectories on the three dimensions and according to three different levels of granularity, the other is the combination of two bidimensional sub-measures centred around a particular dimension. We evaluated our two measures by comparing them to other measures and to the opinion of geographers
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Kathe, Claudia. "Improving mobility after corticospinal tract injury." Thesis, King's College London (University of London), 2016. https://kclpure.kcl.ac.uk/portal/en/theses/improving-mobility-after-corticospinal-tract-injury(ca3be9d6-a198-42ef-bb32-ab28a59e273c).html.
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The corticospinal tract is one of the major motor tracts in the spinal cord. Traumatic injury to it through spinal cord injury or stroke results in loss of dexterity, coordinated locomotion and fine motor function. With time the spinal circuitry adapts, which may result in spasticity. This thesis is a characterisation of a corticospinal tract injury in a rodent model and evaluates three different treatments, which aim to improve functional recovery post-injury. The first result chapter describes the unilateral pyramidotomy surgery, which lesions the corticospinal tract at medullary level in the brainstem. I performed different behavioural tests assessing motor and sensory function, which revealed sustained deficits. Furthermore, I developed 3 different neurophysiology protocols, which assess functional neurophysiological recovery following sprouting of the uninjured corticospinal tract. I found direct cortical stimulation in combination with EMG recordings from a forelimb muscle (the extensor carpii radialis) is most suitable for longitudinal neurophysiological monitoring of corticospinal tract plasticity. Two of the result chapters evaluate two different gene therapies, which modulate intrinsic neuronal properties. In each, we transduced the motor cortex with a regeneration-associated gene. First, we overexpressed protein tyrosine phosphatase, non-receptor type 2, which also may act as a transcription factor. I performed a unilateral pyramidotomy lesion and treated the unaffected corticospinal tract to increase sprouting. The second gene therapy we tested was with ribonuclease inhibitor 1, which inhibits ribonucleases that are degrading RNA. I performed a cervical lateral hemisection and treated the lesioned corticospinal tract to increase regeneration. To assess if these treatments were effective, I performed behavioural testing, neurophysiology and immunohistochemistry. Both treatments, with Ptpn2 and RNH1, improved functional recovery, neurophysiological outcomes and increased plasticity. In the last result chapter, I performed a bilateral corticospinal tract lesion/pyramidotomy, which causes spasticity through spinal circuitry maladaptations. First, I characterised spasticity behaviourally by developing a new open-field scoring system, neurophysiologically with two different preparations assessing reflex pathways and anatomically by looking at excitatory and inhibitory spinal networks. Next, I treated these rats with intramuscular neurotrophin-3, which is developmentally important for patterning of spinal reflex pathways. Rats had reduced spasticity and improved functional locomotor recovery. In conclusion, I have evaluated three different treatments after corticospinal tract injury, which all improved functional, neurophysiological and anatomical outcomes.
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Oliveira, Elisa Quint de Souza de. "Áreas marginais às rodovias estaduais: segurança e mobilidade em Florianópolis, SC Brasil." Universidade do Estado de Santa Catarina, 2012. http://tede.udesc.br/handle/handle/1360.
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Previous issue date: 2012-06-14<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>Marginal areas of the State Highways and Roads, the safety e mobility in Florianopolis, SC Brazil The objective with this research is to investigate the relation between the protection of the marginal areas of the State Highways and Roads, the safety e mobility in Florianópolis considering; the specific legislation that rules the usage of these areas, the registered cases at the related Public Office and the public policies that foresee the planning of these areas. The Official Track is used as a concept and theoretical reference. From different approaches and understanding that through appropriated public policies, it is possible to build a plan that safeguard these marginal areas providing safety, and guaranteeing urban mobility compromised by the agglomerations and disordered occupations. Other concept is the Urban Mobility, regarded as essential to the quality of life guaranty, allowing city access and the sustainable urban development. The methodology used as form of approach will be qualitative, based on bibliographical research, documental and pre-structured interviews on the effort to join the legislation regarding the subject, the techniques applied to the area s management, the experience from the subjects involved and the real cases, both lasts chosen by opened administrative procedures at the responsible office for roads and highways in the Florianopolis County<br>O objetivo com a pesquisa é investigar a relação entre a proteção das áreas marginais às rodovias estaduais, a segurança e a mobilidade em Florianópolis, considerando a legislação específica que disciplina o uso desses espaços, os casos concretos de ocupação registrados no órgão público responsável e as políticas públicas que vislumbrem o planejamento dessas áreas. Como referencial teórico, o conceito norteador é o de faixas de domínio, a partir de diferentes abordagens, entendendo que por meio de políticas públicas adequadas é possível construir um projeto de ordenamento que salvaguarde as margens das rodovias, proporcionando a segurança e garantindo a mobilidade urbana, comprometida com as aglomerações geradas pela ocupação desordenada. Outro conceito norteador é o de Mobilidade Urbana, entendida como elemento essencial para a garantia da qualidade de vida, permitindo o acesso à cidade e o desenvolvimento urbano sustentável. A metodologia empregada como forma de abordagem do tema será a qualitativa baseada em pesquisa bibliográfica, documental e entrevistas semiestruturadas na tentativa de unir a legislação sobre o tema, a técnica aplicada para a gestão do espaço, a experiência dos envolvidos e os casos reais, estes últimos colhidos por meio de procedimentos administrativos em trâmite no órgão com circunscrição sobre as rodovias estaduais no município de Florianópolis
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Ruggieri, Flavia. "Environmental mobility of potentially toxic trace elements of Andean volcanic ashes." Doctoral thesis, Universitat de Barcelona, 2011. http://hdl.handle.net/10803/39082.
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This research investigate the geochemical environmental impact of ancient ash deposits erupted to hundreds of thousands to several million years ago in the southern Puna and neighbouring areas (Argentina), Uruguay and five historical eruptions occurred over a 20-year period in the Andes. In the latter case, pristine ash samples of Cophue, 2000, Lonquimay, 1988, Llaima, 2008, Chaiten, 2008, and Hudson, 1999 eruptions were studied. The main purpose of this research is to investigate the geochemical environmental hazard posed by different types of volcanic ashes in general, and from the Andes, in particular. The specifics aims of this research are:(1) to develop an analytical methodology for the physico-chemical characterisation of volcanic ash;(3) to propose a new ash leaching methodology that can be useful both for recent and ancient volcanic ashes (Single Batch Leaching Test, SBLT);(4) to recognize the geochemical impact occurring after the deposition of volcanic ash on the environment through leaching experiments (Batch leaching tests, Column leaching tests, and Sequential Extraction Scheme). The main conclusions extracted from this research can be summarised as follows:(1) The physico-chemical information of ashes (mainly the morphological features by SEM, grain-size distribution by laser diffraction and Potential toxic trace elements identification and quantification of the bulk ashes) highlights the main environmental concerns related to the studied ashes and it lays the foundation of the basic knowledge required to understand the ash leaching. (2) The main body of this research has been to propose a proved methodology for a single batch leaching test (SBLT) with deionised water in order to obtain information on short term leaching behaviour of volcanic ash identifying, qualitatively and quantitatively, the potentially hazardous elements being rapidly released from both recently erupted and ancient volcanic ashes. The proposed procedure is completed within few hours and its design is simple, concise and reliable.(3) The application of the SBLT (with deionised water) method developed in this research have allowed to define the potential geochemical impact of the volcanic ashes investigated on the environment. This study shows that major elements with high mobility are Ca, Mg, Na, Si, K, and Al. Puna and Uruguay ashes could release in the environment the same trace elements (i.e., P, Ti, Fe, Mn, Zn), however, in different concentrations. These are macro- and micronutrients evidencing the fertilizing potential of the ashes. Chaiten ashes showed high concentrations for As, Pb, Fe, and Zn, whilst the other samples (i.e., COP, LON, LLA, and HUD) could release principally P, Ti, Mn, Ni, Zn, and Pb. Most of these are potentially toxic trace elements (PTTE) even at very low concentration. They are included in the drinking water guidelines due to their potential toxicity and must be especially monitored in the environmental assessment of these ashfall deposits. (4) Dynamic leaching tests conducted on raw ashes and grain-size fractions allowed to define the element implied during glass and mineral dissolution. From the data nowadays available on the temporal leaching of Andean rhyolitic ashes (from CVZ to SVZ), the association between ash dissolution and some trace elements (As, Mo, V, B, and U) through laboratory experiments was demonstrated. This study represents a great advance on the knowledge of the geochemical environmental hazard posed by volcanic ashes, in general, and from the Andes, in particular. In terms of methodological approach, the developed method of SBLT is a very important contribution because there is a need to harmonize the batch tests applied to volcanic ash. In addition, column leaching test and sequential extraction scheme complement the information obtained by SBLT and facilitate decision making on management of geochemical hazard associated with the volcanic ash fall.
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Lockwood, Cindy Louise. "Biogeochemical processes and trace element mobility in alkaline waste affected soils." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/7555/.
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High pH leachates can mobilise oxyanion forming elements from alkaline waste, such as iron and steel slags and bauxite ore processing residue, into the wider environment. Red mud is a highly alkaline waste product from bauxite ore processing. It contains elevated concentrations of oxyanion forming elements such as Al, As, V and Mo that are mobilised at high pH together with other trace metals including Cu and Ni. The red mud spill at Ajka, Hungary released 1 million m3 of caustic red mud into the surrounding area. As part of the initial clean-up, some thinner red mud deposits (< 5 cm) were ploughed into fields to prevent dust formation whereas wetland areas were left untreated. This study used aerobic and anaerobic batch microcosms together with XAS spectroscopy, (HPLC)-ICP-MS and solid phase extraction techniques to investigate the effects of red mud addition to unaffected soils with respect to biogeochemical processes and trace element release. Experiments were designed to be analogous to soil conditions following the remediation efforts. The results showed that the effect of red mud addition to soils was highly dependent upon soil properties, experimental pH, and total organic carbon (TOC) content. As and V were found to be persistently mobile under both aerobic and anaerobic conditions. Red mud addition to soils with a high TOC content mobilised high aqueous concentrations of organic matter complexing metals such as Cu, Ni and V under anaerobic conditions. Gypsum addition to red mud affected soils showed a reduction in aqueous oxyanion concentrations compared to soils with red mud addition alone indicating that it is potential ameliorant for red mud contaminated soils. The results showed that the extensive remediation efforts by the Hungarian authorities were justified but that red mud should be used with caution as a soil amendment.
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Sukkariyah, Beshr. "Trace Metals Mobility in Soils and Availability to Plants from a Long-Term Biosolids Amended Soil." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/11098.
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The long-term mobility and availability of trace metals has been cited as a potential hazard by critics of EPA 503 rule governing the land application of biosolids. The purpose of this research was to investigate the long-term effects of biosolids application on trace metals distribution and mobility. A single application of aerobically digested biosolids was applied to 1.5 x 2.3 m confined plots of a Davidson clay loam (clayey, kaolinitic, thermic, Rhodic Paleudult) in 1984 at 0, 42, 84, 126, 168, and 210 Mg/ha. The highest biosolids application supplied 4.5, 760, 43, and 620 kg ha-1 of Cd, Cu, Ni, and Zn, respectively. Radish (Raphanus sativus L.), lettuce (Lactuca sativa Var longifolia) and barley (Hordeum vulgare) were planted at the site. Soils were sampled to a depth of 0.9 m and sectioned into 5 cm increments after separating the Ap horizon. Total (EPA 3050B), available (Mehlich-I), sequential extraction, and dispersible clay analyses were performed on samples from the control, 126 Mg/ha and 210 Mg/ha treatments. Extractable (0.005 DTPA, 0.01 M CaCl2, and Mehlich-1) Cd, Cu, Ni, and Zn were measured on 15 cm-depth samples from each plot. Simple linear regression between plant metal concentration and biosolids-added trace metals were computed to determine uptake coefficients (UC) of crops for each metal as outlined by USEPA Part 503 Rule. Results indicated that more than 80% of the applied Cu and Zn are still found in the topsoil where biosolids were incorporated with slight enrichment down to 0.3 m. Biosolids application increased the concentration of trace metals in all the extracted fractions, with a large proportion of Zn and Cd present in the available forms. The major portion of Cu, Zn and Ni was associated with the metal-oxides fraction. Biosolids treatments had no significant effect on the yield of the crops. Plant uptake of trace metals differed among crops. Plant tissue metal concentrations increased with biosolids rate but were within the normal range for these crops. Trace metals concentration in plants generally correlated well with their concentrations extracted with 0.005 M DTPA, 0.01 M CaCl2 and Mehlich-1. Mehlich-1 gave the highest correlation coefficients for Cu and Zn and, therefore, was the most reliable in predicting their availability and uptake by the crops grown. Availability of trace metals as measured by Mehlich-I, DTPA, and CaCl2 extraction were higher in amended plots as compared to the control and increased linearly in response to biosolids addition. Metal concentration in the plants exhibited a plateau response in most cases. Several linear increases were observed in some cases in 2003 when the soil pH decreased below 5.5. The uptake coefficients values generated for the different crops were in agreement with the values set by the Part 503 Rule.<br>Ph. D.
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Aggarwal, Jugdeep K. "The mobility of trace elements and boron isotopes in Icelandic hydrothermal systems." Thesis, University of Bristol, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294571.
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Saunders, Ruth. "Investigations of processes controlling trace element mobility in Scottish freshwater loch sediments." Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/12901.
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Botes, Paul Johannes. "Investigation of mobility of trace elements in river sediments using ICP-OES." Pretoria : [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-01182005-091457.
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Lasley, Katrina. "Chemistry and Transport of Metals from Entrenched Biosolids at a Reclaimed Mineral Sands Mining Site in Dinwiddie County, Virginia." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/33994.
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Deep row incorporation of biosolids is an alternative land application method that may allow higher than currently permitted mine land reclamation application rates. Biosolids treated by various processes possess characteristics that uniquely affect metal solubility and mobility due to their influence on metal speciation. The objectives of this research were to compare the effects of biosolids stabilization type and rate on heavy metal solubility, mobility, and speciation. Two rates each of Alexandria, (Virginia) anaerobically digested (213 and 426 dry Mg ha-1) and Blue Plains (Washington, DC) lime-stabilized (329 and 657 dry Mg ha-1) biosolids were placed in trenches at a mineral sands mine reclamation site in Dinwiddie County, Virginia in June and July 2006. Vertical and lateral transport of heavy metals from the biosolids seams were determined by analyzing leachate collected in zero tension lysimeters below the trenches and suction lysimeters adjacent to the trenches. Chloride (Cl-), sulfate (SO42-), nitrate (NO3-), phosphate (PO43-), dissolved organic carbon (DOC), and pH were also determined within the dissolved fractions (< 0.45 µm) collected on September 8, 2006, November 3, 2006, January 5, 2007, June 8, 2007, and September 7, 2007 as input for the speciation program MINTEQA2. Silver, Cd, Pb, and Sn did not move vertically or laterally to any significant extent. Lime-stabilized biosolids produced higher cumulative metal mass transport per sampling period for Cu (967 g ha-1), Ni (171 g ha-1), and Zn (1027 g ha-1) than the anaerobically digested biosolids and control during the 15-month period following entrenching. Barium mass loss was similar for both biosolids. All metals moved primarily with particulates. MINTEQA2 predicted the majority of the metals within the dissolved fraction were present as free ions. As pH decreased and time increased, the amount of association with fulvic acids decreased allowing more free ions and binding with inorganic ligands. Little movement into groundwater demonstrates that anaerobically digested and lime-stabilized biosolids can be land-applied at high rates with little concern of heavy metal contamination of groundwater under these conditions.<br>Master of Science
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Magnani, Antonio. "Simulazione di mobilità in ambito veicolare." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/4581/.
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Schindl, Roland [Verfasser]. "Ultra trace analysis and mobility of palladium emissions from automotive catalytic converters / Roland Schindl." Ulm : Universität Ulm. Fakultät für Naturwissenschaften, 2015. http://d-nb.info/1075253357/34.
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Düker, Anders. "Natural aquatic colloidal matter : characteristics and impact on the mobility of trace metals and organics /." Linköping : Tema, Univ, 1998. http://www.bibl.liu.se/liupubl/disp/disp98/arts180s.htm.
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Hindersmann, Iris [Verfasser], and Tim [Akademischer Betreuer] Mansfeldt. "Trace elements in floodplain soils - effects of redox conditions on the mobility of trace elements and volatilization of mercury / Iris Hindersmann. Gutachter: Tim Mansfeldt." Köln : Universitäts- und Stadtbibliothek Köln, 2014. http://d-nb.info/1060190427/34.
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Maraška, Arūnas. "Mobilios lauko kavinės projektas." Bachelor's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100907_095913-73647.
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Šią kavinę projektavau iš sunkvežimio priekabos, kurios šonai atsilenkia ir suformuoja pakylą. Ant vidurinės platformos dalies suprojektavau barą su sandėliu, o aplinkui išdėsčiau staliukus su kėdėmis. Visa tai dengia brezentinis stogas kurio išskleidimo mechanizmas sumontuotas priekabos stogo dalyje. Taip pat, esant poreikiui, bus sudarytos sąlygos aplink šią kavinę sustatyti papildomus stalus ir kėdes.<br>Šią kavinę projektavau iš sunkvežimio priekabos, kurios šonai atsilenkia ir suformuoja pakylą. Ant vidurinės platformos dalies suprojektavau barą su sandėliu, o aplinkui išdėsčiau staliukus su kėdėmis. Visa tai dengia brezentinis stogas kurio išskleidimo mechanizmas sumontuotas priekabos stogo dalyje. Taip pat, esant poreikiui, bus sudarytos sąlygos aplink šią kavinę sustatyti papildomus stalus ir kėdes.
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Oyewumi, Oluyinka. "The Release and Mobility of Trace Elements from Poultry Litter: Insights from Field, Laboratory and Modeling Experiments." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77156.
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Organoarsenic compounds and trace elements are added to poultry feed for disease control and improved productivity. These elements are excreted into poultry litter, which is land applied as fertilizer. This study utilized field and laboratory experiments to address the mobility of arsenic (As) and other litter-derived elements within the Broadkill River watershed, DE, a region of intense poultry production. For the first project, a litter application experiment was conducted at an instrumented field site in Sussex Co., DE. After establishing baseline geochemistry of soil water, ground water, and surface water at the site, poultry litter was then applied, followed by post litter application monitoring. Results showed low concentrations of As and other litter-derived elements in soil water; little impact was measured on ground or surface water. Mass balance calculations suggest that the majority of mass of leached elements was accounted for by uptake in underlying soils. The second project examined the impact of long-term litter application on chemical signatures of As, copper (Cu), zinc (Zn) and phosphorous (P) in stream sediments within the Broadkill River watershed. Sediment samples were collected from both upgradient and downgradient reaches within the watershed. Using GIS to overlay hydrology and land use, statistical relationships between As, Cu, Zn and P enrichment factors and land use were examined. Results did not show a relationship between these elements and agricultural land use, but did show a correlation between some of the elements and residential land use. The third project examined the influence of dissolved organic carbon (DOC) on the mobility of As, Cu, Zn and P using laboratory column experiments with soil from the field site. Two influent solutions were used: poultry litter leachate and a simulated solution of similar element concentrations, pH, and ionic strength but without DOC. Results showed that DOC enhanced the mobility of all four elements, but that even with DOC, 60-70% of the Zn, As and P mass was retained within the soil. Cu was fully mobilized by DOC. Patterns of breakthrough curves (BTCs) and mass calculations suggest that the behavior of these litter-derived elements in the column is controlled by both adsorption (including competitive) to soils and complexation with DOC.<br>Ph. D.
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Marcel, Olivier. "Des horizons à la trace : géographie des mobilités de l'art à Nairobi." Thesis, Bordeaux 3, 2014. http://www.theses.fr/2014BOR30061.
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Cette thèse consiste en une géographie des lieux et des circulations de l’émergence artistique dans une métropole du Sud. Elle se situe au croisement entre une géographie urbaine, soucieuse des agencements socio-spatiaux à l’intérieur desquels s’organise l’existence « ordinaire » d’une activité en train de se faire, et une géographie de l’art qui place les trajectoires spatiales des faits artistiques au cœur de l’analyse. Capitale postcoloniale, métropole est-africaine et périphérie d’une « économie mondiale d’archipel », Nairobi est un terrain de la rencontre entre métropolisation et globalisation. Dans le sillon des théories géographiques de la mondialisation, cette recherche propose de documenter et de cartographier les reconfigurations de l’espace artistique qui résultent de ces dynamiques. L’originalité de cette thèse est de rassembler l’ensemble des scènes et des productions artistiques d’une ville sur le dénominateur commun de la dimension spatiale de leurs circulations. Le matériau étudié (discours et curriculum vitae d’artistes, activités et archives de centres d’art) permet de confronter des circulations effectives à des horizons d’accomplissement différenciés, dont la trame est faite d’une ruralité encore prégnante et la connectivité d’une métropole mondialisée. La méthode développée relève de la traçabilité, dont la base est l’enquête par observation. Une exposition, une performance, une bourse de voyage, la visite d’un commissaire d’exposition, d’un collectionneur ou d’un mécène, les circulations quotidiennes d’un artiste et ses modes de socialisation, tous ces déplacements individuels, matériels, idéels et financiers constituent la matière première de la géographie proposée dans cette thèse. Comprise comme l’articulation entre, d’une part, les compétences et les tactiques spatiales des artistes et, d’autre part, les moyens matériels et institutionnels de gestion de la distance, la mobilité artistique interroge les conditions et le sens des déplacements autant que le devenir des acteurs engagés<br>This Ph.D. thesis tackles the places and circulations involved in the making of art in a southern metropolis. It is situated at the crossroads of an urban geography concerned with the social and spatial layout through which this “ordinary” activity is organized, and a geographical approach of art that places actors’ trajectories at the heart of the analysis. Capital city in a postcolonial State, East African metropolis and periphery of the “global archipelagic economy”, Nairobi is a case of the encounter between metropolization and globalization. In the trail of the theories on the worlding of material geography, this study aims at documenting and mapping the reconfigurations of art space triggered by these dynamics. The novelty of this thesis is to assemble the entire range of art scenes and products of a city, using the common thread that is the spatial dimension of their circulations. The material studied (artists’ discourse and curriculum vitae; art centres activity and archive) takes on both the measureable circulations of artists while confronting them to their horizon of accomplishment. These are made up of the persistence of strong rural ties and the connectivity of a globally connected city. The method deployed relies on the notion of traceability and is based on a qualitative survey through observation. An exhibition, a performance, a mobility grant, a visiting curator, collector or benefactor, the daily circulations and socializing of an artist: all these individual, material, ideal or financial movements constitute the raw material of this research. The notion of art mobility is here understood as the articulation between artists’ agency and spatial tactics on the on hand, and the material and institutional means of dealing with distance on the other hand. Art mobility questions the conditions, directions and meanings of these movements as much as the growth of the actors engaged
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Tatto, Jilmar Augustinho. "Mobilidade urbana em São Paulo: aplicação de soluções imediatas e eficazes." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-23092015-131419/.
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Este trabalho apresenta o impacto de medidas de gestão como a implantação das faixas exclusivas no tráfego da cidade de São Paulo que, associada à reestruturação semafórica, tem melhorado a mobilidade urbana em São Paulo. Para tanto, traça-se o cenário da mobilidade urbana e, em seguida, analisa-se o quanto a implantação de mais de 400 km de faixas exclusivas nos últimos dois anos impacta no aumento da velocidade média dos ônibus e na redução do crescimento da lentidão do tráfego. A experiência de outras grandes cidades indica que a adesão a novas ferramentas de gestão é alternativa viável para a promoção de avanços qualitativos no transporte coletivo urbano e no transporte em geral, bem como na integração entre modais de transporte motorizado e não motorizado, no deslocamento de pessoas e cargas com mais eficiência e segurança. Por fim, apontam-se outras possibilidades tecnológicas que poderão ampliar os resultados positivos obtidos na mobilidade paulistana.<br>This work presents the impact of management measures such as the establishment of exclusive tracks in the city of São Paulo traffic that is associated with the semaphore restructuring, has improved urban mobility in São Paulo. To do so, construct the scenario of urban mobility and then analyzed how much the deployment of more than 400 km of exclusive tracks for the past two years impacts on increasing the average speed of buses and reduced growth of traffic slowdowns. The experience of other major cities indicates that membership of the new management tools is a viable alternative to the promotion of qualitative advances in urban mass transit and transportation in general, as well as in the integration between motorized transport modal and non-motorized, the displacement of people and cargo with more efficiency and safety. Finally, point out other technological possibilities that can magnify the positive results obtained in mobility in Sao Paulo.
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Gordon, William. "Mobile livelihoods: a case study of Lithuanian international long-haul truck drivers." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110607_135718-12080.
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Research Question: how are Lithuanian international long-haul truck drivers’ livelihoods constructed in terms of work, home, and everyday life?
Research Problem and significance. The aim of this research is to look at work, home, and everyday life in the context of mobility and mobile livelihoods in Lithuanian international long-haul truckers. Portrayals of truckers in media and pop culture are often negative or sensationalized, including stories about truck accidents, smuggling, immoral behaviors, or problems with the law. This research is a response to such perceptions, motivated by the fact that there is no qualitative research on truck drivers in Lithuania.
Research Tasks
1. Create a theoretical base for analyzing and interpreting mobile lives using various theoretical approaches on mobility, place, home, community, and boundaries.
2. Present and analyze empirical work from the field of Lithuanian long-haul truck drivers based on emic frameworks of ‘kasdienybė’ and ‘namai’.
3. Apply theoretical approach of mobile livelihoods along with emic frameworks of ‘kasdienybė’ and ‘namai’ from the Lithuanian case toward an analysis of Cameroon long-haul truck drivers’ work-lives.
Methods. Fieldwork conducted with Lithuanian international long-haul truck drivers who spent 5-6 days or more on the road at a time, with just 2-4 days per month ‘at home’ (in Lithuania). Empirical section relies on two primary informants with whom I spent a total of 3 ½ weeks traveling. Research... [to full text]<br>Tyrimo klausimas. Ką reiškia namai, darbas bei kasdieniniai poreikiai Lietuvos tarptautinių tolimųjų reisų vairuotojams, „gyvenantiems ant ratų“ ?
Tyrimo problema ir reikšmė. Šio tyrimo tikslas yra pažvelgti į Lietuvos tarptautinių tolimųjų reisų vairuotojų. kultūrą ir vietą mobilumo ir mobiliojo pragyvenimo kontekste. Lietuvos žiniasklaidoje tolimųjų reisų vairuotojai dažnai yra apibūdinami neigiamai arba hiperbolizuotai, įskaitant pasakojimus apie transportą, nelaimingus atsitikimus, kontrabandą, amoralų elgesį, ar problemas su įstatymu. Šis tyrimas yra atsakas į tokį suvokimą ir motyvuojama tuo, kad Lietuvoje nebuvo atlikta tolimųjų reisų vairuotojų gyvenimo kokybiško tyrimo.
Tyrimo uždaviniai:
1. Sukurti teorinį pagrindą, skirtą analizuoti ir interpretuoti mobilų gyvenimą, taikant įvairius teorinius požiūrius į mobilumą, vietą, namus, bendruomenę ir etninius skirtumus.
2. Pateikti ir išanalizuoti empirinį darbą apie Lietuvos tolimųjų reisų vairuotojus, remiantis eminiais terminais - "kasdienybė" ir "namai".
3. Pagal atliktą analizę, palyginti požiūrį į mobiliojo gyvenimo esmę kartu su eminiais terminais - "kasdienybė" ir "namai" – tarp Lietuvos ir Kamerūno tolimųjų reisų vairuotojų.
Metodai. Taikytas duomenų rinkimas apie Lietuvos tolimųjų reisų vairuotojus, kurie vidutiniškai praleidžia 5-6 dienas ar daugiau kelyje, su 2-4 dienomis per mėnesį "namuose" (Lietuvoje). Empirinio skyriaus duomenys pagrįsti dviejų pagrindinių asmenų, su kuriais aš praleidau 3 ½... [toliau žr. visą tekstą]
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Lindegren, Daniel. "Visualisera personuppgifter i ett tidslinjegränssnitt : Utvärdering av ett mobilt användargränssnitt till Data Track i A4Cloud-projektet." Thesis, Karlstads universitet, Handelshögskolan, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-36277.
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Syftet med denna C-uppsats var att implementera ett visualiseringskoncept för att presentera data i ett tidslinjegränssnitt med hjälp av Font Awesome-ikoner inom A4Cloud-projektet. Den huvudsakliga målgruppen utgör personer som främst arbetar inom A4Cloud-projektet. För att kunna belysa brister i visualiseringskonceptet genomfördes användartester där testpersonerna fick använda sig av det upprättade tidslinjegränssnittet samt en konstruerad plattform för att besvara ikoners betydelse. Både kvalitativa intervjuer samt statistiska framställningar genomfördes under studien. De slutsatser som kan dras från denna studie är att några element var svåruppfattade som interaktiva element och svåra att åtskilja från resten av gränssnittet. Testpersoner, blev under studien, tillfrågade under intervjun om de kunde tänka sig använda tidslinjegränssnittet i sin vardag. Orosfaktorn verkar inte ha spelat någon roll när testpersonerna besvarade tidigare nämnda intervjufråga, utan behovet att vilja ha koll på sina delningar med diverse tjänster verkar vara det som avgör.<br>A4Cloud
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Rustioni, Greta [Verfasser], and Hans [Akademischer Betreuer] Keppler. "Trace Element Mobility in Aqueous Fluids and the Cause of Melting in Subduction Zones / Greta Rustioni ; Betreuer: Hans Keppler." Bayreuth : Universität Bayreuth, 2021. http://d-nb.info/1239177704/34.
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Taneez, Mehwish. "Stabilisation d’un sédiment marin pollué en utilisant des résidus de bauxite : évaluation de la mobilité d’éléments trace." Thesis, Nice, 2016. http://www.theses.fr/2016NICE4036/document.
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Dans les zones portuaires un dragage régulier des sédiments est indispensable afin de maintenir une profondeur satisfaisante des voies de navigation. Dans ce travail, nous avons cherché à étudier la faisabilité d'un traitement de stabilisation en mélangeant 5% et 20% les résidus de bauxite (Bauxaline®, Bauxsol et Bauxaline® neutralisé) avec les sédiments marins de dragage pollués. L'efficacité de cette méthode de traitement a été évaluée en mesurant la concentration en éléments traces lixiviés et la toxicité des lixiviats des sédiments. L’application d’amendements de 20% résidus de bauxite a permis une réduction significative la concentration des éléments traces cationiques de 40 à 80%, et la toxicité des lixiviats. Quel que soit l’amendement, une faible efficacité de la stabilisation a été observée pour les éléments anioniques (As, Mo)<br>Marine sediments concentrate various pollutants and subsequent sedimentation of harbors and ports require periodic dredging to maintain satisfactory depth of waterways. Direct land deposition of contaminated marine dredged sediments pose risk to the environment due to possible leaching of trace elements. In this context, we aimed to study the feasibility of trace elements stabilization by mixing 5% and 20% of bauxite residues (bauxaline®, bauxsol and neutralized bauxaline®) with composted dredged marine sediment. The treatment efficiency was evaluated by monitoring the leached trace elements concentration and toxicity of sediment leachates. 20% amendment application successfully stabilized cationic pollutants (Cu, Cd, Zn) up to 40-80%, and decreased the toxicity of sediment leachates. Whereas, anionic pollutants (As, Mo) were less immobilized require further investigation
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Kakonyi, Gabriella. "The oxidative transformation of green rust sulphate and its influence on the mobility of trace elements : applications to remediation processes." Thesis, University of Leeds, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.539697.
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Qasim, Bashar Hussein. "Détermination, spéciation et biodisponibilité des éléments traces métalliques dans les sols contaminés et technosols." Thesis, Orléans, 2015. http://www.theses.fr/2015ORLE2069/document.
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Cette thèse a porté sur la détermination et l’étude écodynamique d’éléments traces métalliques sur des technosols fortement contaminés en métaux et metalloïdes en contexte de revégétalisation naturelle ou de phytoremédiation. Deux schémas d'extractions séquentielles ont été utilisés conjointement à des extractions sélectives en parallèle avec la détermination de la concentration totale dans les sols, de la concentration totale dissoute dans les eaux porales, du pool labile (sondes DGT) et des tests de germination avec des haricots nains pour étudier la spéciation, la mobilité et la phytodisponibilité de métaux et métalloïdes (Zn, Pb, Cd, As et Sb) pour les technosols de deux sites post-minier (La Petite Faye) et industriel (Mortagne-du-Nord). De plus de jeunes plants de P. euramericana Dorskamp ont été cultivés en rhizobox sur les technosols de Mortagne-du-Nord pour étudier l’effet rhizosphèrique sur la mobilité des métaux. Enfin l’effet de l’addition d’azote sous forme de nitrate et d’ammonium sur le comportement de ces métaux a été également étudié pour P. euramericana Dorskamp sur ces mêmes sols. Malgré les fortes concentrations totales en métaux et métalloïdes dans les sols du site de La Petite Faye, la mobilité de ces éléments potentiellement toxiques est limitée car associés à la fraction résiduelle. La phytodisponibilité est également limitée et corrélée avec le pool labile des technosols. La culture de P. euramericana Dorskamp a généré un effet rhizosphèrique caractérisé par une augmentation de la valeur du pH et la concentration de carbone organique dissout (COD) de la solution de sol ainsi qu’une diminution des concentrations totale dissoute des métaux (Zn, Pb et Cd) dans la solution de sol. L’addition d’azote sous forme de nitrate et d’ammonium a respectivement augmenté et diminué le pH de la solution de sol et dans le cas de l’ammonium a augmenté également le COD et stabilisé les métaux dans la rhizosphère par rapport aux sols de contrôle<br>This thesis dealt with the determination and study of the ecodynamics of trace metals in technosols highly contaminated in metals and metalloids in the context of natural revegetalisation or phytoremediation. Two sequential extraction schemes were used jointly with selective extractions in parallel with the determination of the total metals concentration in soils, the total dissolved metals concentration in the soil pore water, the metals labile pool (DGT) and germination tests with dwarf beans to investigate the speciation, mobility and phytoavailability of (Zn, Pb, Cd, As and Sb) for technosols of two post-mining (La Petite Faye) and industrial (Mortagne du Nord) sites. Additionally, young plants of P. euramericana Dorskamp were cultivated in rhizobox on Mortagne du Nord technosols to investigate the rhizospheric effect on the mobility of metals. Moreover, the effect of nitrogen addition under nitrate and ammonium on the behavior of these metals has been investigated for P. euramericana Dorskamp for the same soils. Despite the high total metals and metalloids concentration in the La Petite Faye soils, the mobility of these potentially toxic elements is limited because of their association with the residual fraction. The phytoavailability is also limited and correlated with the labile pool of technosols. The culture of P. euramericana Dorskamp generated a rhizospheric effect characterized by an increase of the pH and concentration of dissolved organic carbon (DOC) in the soil pore water and a decrease in the total dissolved concentration of metals (Zn, Pb et Cd) in the soil pore water. The addition of nitrogen under nitrate or ammonium respectively increased and decreased the soil pore water pH and in the case of ammonium the DOC also increased and stabilized metals in the rhizosphere in comparison to control soils
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Tapia, Zamora Joseline Soledad. "Sources, Mobility and Bioavailability of Trace Metals and Metalloids in the Historically Mining and Smelter Impacted Altiplanean City of Oruro, Bolivia." Tesis, Universidad de Chile, 2011. http://www.repositorio.uchile.cl/handle/2250/102587.
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Tafuri, Mary Anne. "'Marrying in and eating out' : mobility, food and social dynamics in Bronze Age southern Italy : trace element analysis at Sant'Abbondio (Pompeii, Naples)." Thesis, University of Southampton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412268.
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Abi, ghanem Carine. ""speciation" des trois elements trace mercure, plomb et cadmium dans les sediments marins des zones cotieres libanaises." Phd thesis, AgroParisTech, 2008. http://pastel.archives-ouvertes.fr/pastel-00005015.
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Les profils verticaux des concentrations, les sources et la mobilité de Pb, Cd et Hg ont été étudiés dans des carottes sédimentaires prélevées en trois sites typiques de la côte libanaise (Akkar, Dora et Selaata). Akkar est un site éloigné de toute influence directe de contamination chimique, Dora est soumis à l
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Costantini, Hervé. "La mobilité sociale : Modèles et traces." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2012. http://tel.archives-ouvertes.fr/tel-00770978.
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L'avenir de la communication est perçu comme étant quasiment exclusivement constitué de nœuds mobiles évoluant dans un réseau mobile. Dans ce contexte, différentes approches contribuent continuellement à l'amélioration directe ou indirecte des délais d'acheminement des informations échangées entre les utilisateurs, dont :- l'analyse des traces;- l'évaluation des performances ;- les services de localisation;- le routage. Nous décrivons chacun de ses thèmes et proposons des solutions faisant évoluer l'état de l'art. Celles-ci prennent appui sur des méthodes et outils tels que :- les Réseaux de Petri, pour l'analyse des traces ;- les modèles de mobilité, pour l'évaluation des performances;- l'introduction du social dans les services de localisation;- la mise en place d'une nouvelle métrique pour le routage. Nous montrons comment ces solutions concourent de façon complémentaire les unes avec les autres, à améliorer l'expérience de l'utilisateur.
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Kaschl, Arno. "Trace metal binding by organic matter from municipal solid waste compost and consequences for mobility in compost amended soils under semiarid conditions (Gaza strip) /." Aachen : Shaker, 2001. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=009571814&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Gounou, Catherine. "Mobilité des éléments traces métalliques dans les sédiments : couplage et comparaison des approches chimique et microbiologique." Thesis, Paris Est, 2008. http://www.theses.fr/2008PEST0074/document.
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Les activités anthropiques entraînent une contamination des sédiments de rivière en de nombreux polluants et en particulier en éléments traces métalliques (ETM). Si la majorité des ETM se retrouvent piégés dans les sédiments, ceux-ci peuvent être remobilisés et passer en solution dans certaines conditions physico-chimiques et sous l’action des microorganismes autochtones. Les métaux relargués peuvent alors constituer un danger potentiel pour les organismes vivants dans les sédiments et dans la colonne d'eau. Dans le cas des sols, l’impact de l’activité microbienne autochtone sur la mobilité des ETM a souvent été rapporté. Cependant une telle activité de solubilisation n’a été que rarement étudiée dans le cas des sédiments. Une telle connaissance est pourtant importante pour la prédiction du comportement des métaux contenus dans les sédiments et la gestion de ces derniers, notamment lors de leur stockage suite aux opérations de dragage. Dans ce contexte, l’objectif de cette thèse a été de comprendre et d’évaluer l’importance de certains des processus microbiens et chimiques de mobilité des ETM dans les sédiments en conditions anaérobies. La première phase de notre étude qui a consisté à incuber des sédiments de Seine et de Marne en milieu anaérobie dopé en glucose avait pour objectif d’étudier la corrélation entre le métabolisme microbien et le comportement des métaux en solution et dans les sédiments. Dans ces conditions opératoires, une forte solubilisation du fer et du manganèse (sous forme réduite) associée à une solubilisation de métaux traces (Co, Cu, Ni) a été mise en évidence, ce qui a laissé supposer l’intervention de bactéries ferri-réductrices dans les phénomènes observés. Une activité fermentaire importante a été observée et caractérisée par la production d’acides organiques majoritaires tels que les acides acétique et butyrique. Un tel résultat souligne l’importance des bactéries fermentatrices dans les phénomènes de dissolution observés. La deuxième étape de ce travail a consisté à confirmer l’importance de l’activité ferri-réductrice et à en identifier les acteurs principaux. Les analyses moléculaires menées ont montré que les bactéries ferri-réductrices majoritairement identifiées, appartiennent aux espèces Clostridium butyricum et Paenibacillus polymyxa. L’utilisation d’un modèle géochimique nous a permis de montrer que les voies métaboliques supportant la réduction du fer et la mobilité des métaux étaient les fermentations butyrique et acétique. La troisième étape a consisté à comparer les impacts directs (réduction enzymatique) et indirects (propriétés des acides organiques produits) de Paenibacillus polymyxa et Clostridium butyricum sur la mobilité du fer, du manganèse et des autres métaux. Une telle étude a montré que les acides organiques produits (acétique, lactique, succinique, propionique et butyrique) ont un très faible impact sur la solubilisation aux pH rencontrés dans les sédiments et que la réduction enzymatique microbienne est le principal mécanisme de dissolution des éléments métalliques en milieu anaérobie<br>Antropic activities lead to the metallic contamination of river sediments. Most of trace metals are sorbed on sediments but a part of them can be released into aquatic environment when environmental conditions are modified. This is often due by the autochthonous microbial activity. Microbial activites and their consequences on the mobility of metals have been widely studied in soils. Metals are released through direct or indirect microbial mechanisms. Such studies in the case of sediments are very seldom. However, it can be usefull to understand the microbial mechanisms of metal release in sediments, and particularly for a good management of dredged sediments. In this environmental framework, the aim of this research work was to understand and to evaluate the role of the microbial and chemical mechanisms in the release of metals from river sediments in anaerobic conditions. Firstly, sediments from the Marne and Seine rivers were incubated in anaerobic conditions. A high solubilisation of iron and manganese occurred associated to the solubilisation of trace metals (Co, Cu, Ni, Pb). Meanwhile, organic acids were produced and the medium was acidified. Thus fermentation was supposed to be the main process of microbial metabolism. Furthermore these observations led us to suppose the presence of iron-reducing bacteria. In a second step, the extent of the iron-reducing activity was studied. The main iron-reducing bacteria identified in the Marne sediments belonged to the species Clostridium butyricum and Paenibacillus polymyxa. The use of a geochemical model revealed that fermentation and reduction of iron(III) were the main metabolic pathways. Finally direct (enzymatic reduction) and indirect (complexation with organic acids, acidification) impacts of iron-reducing bacteria on the release of metals were compared. Acidification and organic acids had a weak impact on metal solubility in the range of studied pH (between 6,5 and 5). Enzymatic reduction is the main mechanisms of metal release in anaerobic conditions. Indeed the metallic concentrations can be 40 times higher in the presence of iron-reducing bacteria
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Nafeh, Kassir Lina. "Les métaux lourds dans les engrais phosphatés et les sulfates rejetés par les industries des fertilisants : recherche sur leur transfert et leur mobilité dans les sols libanais." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0332/document.
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Afin d'établir l'impact et le risque lié aux fertilisants chimiques depuis leur fabrication jusqu'à leur amendement sur la contamination des sols par les éléments traces métalliques, une étude de leur mobilité et leur transfert s'avère nécessaire. L'objectif de ce travail de thèse était d'évaluer la source de contamination du sol par les éléments traces autour de l'industrie des fertilisants chimiques et suivre l'évolution temporelle de la mobilité et du transfert de ces éléments dans un profil du sol agricole amendé par des engrais phosphatés du type simple superphosphate (SSP) ou du phosphogypse. Pour cela nous avons utilisé des techniques permettant la caractérisation structurale et minéralogique des sols collectés comme la diffraction des rayons X et la microscopie électronique. Puis une caractérisation chimique des sols collectés concernant la concentration totale des éléments traces et des éléments majeurs a été établie. Comme la mobilité n'est pas stable au cours du temps dépendant de plusieurs paramètres physico-chimiques comme le pH, le potentiel redox, la teneur en matière organique, une extraction séquentielle a été adoptée le long de l'étude au cours du temps et dans le profil du sol amendé jusqu'à une profondeur de 55 cm. En outre, l'absorption des éléments traces par les plantes cultivées sur le terrain agricole amendé par les engrais ou le phosphogypse a été analysée au cours du temps afin d'évaluer le risque lié à la chaîne alimentaire et plus particulièrement la chaîne alimentaire humaine induisant des effets négatifs sur la santé. Une comparaison entre l'application du phosphogypse et celle des engrais a été mise en évidence à la finalité de ce travail<br>To determine the impact and risk of chemical fertilizers, from their manufacture to their amendment, on soil contamination by trace metals, the study of their mobility and transfer would be necessary. The objective of this work was to evaluate the source of soil contamination by trace elements around the industry of chemical fertilizers, and to follow the temporal evolution of mobility and transfer of these elements in the profile of agricultural soil amended by superphosphate (SSP) fertilizers or phosphogypsum. To achieve our objective, we used techniques allowing the determination of structural and mineralogical characterization of collected soil samples, such as X-ray diffraction and electron microscopy. Chemical characterization related to the total concentration of trace and major elements of collected soils was established. As mobility was unstable over time, depending on several physico-chemical parameters such as pH, redox potential, and organic matter content, a sequential extraction was adopted throughout the study over time in the amended soil profile to a depth of 55 cm. In addition, the absorption of trace elements by agricultural crops cultivated over land amended with fertilizer or phosphogypsum was analyzed over time to assess the risk of their transfer to the food chain, especially the human food chain, imposing health hazards. A comparison between the effects of the application of phosphogypsum and phosphate fertilizer was carried out in concluding this work
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Al-Sid-Cheikh, Maya. "Impact des oxydes de fer naturels et des nanoparticules manufacturées sur la dynamique des éléments traces dans les sols de zones humides." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S144.
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La nanoscience est basée sur les changements de propriétés des particules lorsque leur diamètre est inférieur à 100 nm (i.e. nanoparticules, NPs). Devant l’utilisation croissante de tels NPs, et leur déversement probable dans l’environnement, l’évaluation de leurs risques sur la santé humaine et l’environnement est un enjeu majeur. Dans le cadre de la protection des eaux et des sols, l’évaluation de la qualité des eaux de surface est particulièrement importante, notamment dans les zones humides (ZHs), où la dynamique des métaux toxique (i.e. As, Pb, Ni, Cr, Hg) est complexe et dépend des conditions redox du milieu. Comme les NPs de magnétite (nano-Fe3O4), naturelles ou manufacturées, sont reconnues pour leur capacité d’adsorption importante face aux métaux lourds, leurs interactions dans les ZHs ripariennes (ZHRs) avec les ETMs restent critiques quant à leurs impacts directs ou indirects. Ainsi, l’objectif de cette thèse était d’étudier le rôle des nano-Fe3O4 manufacturées (~10nm) et des oxydes de fer naturels sur la dynamique des ETMs dans les eaux de surfaces et les sols de ZHRs. Ainsi, dans un premier volet portant sur des précipités colloïdaux naturels provenant de produits de reoxydation en milieu riparian (soumis à des oscillations redox), la distribution spatiale des éléments a été effectuée par cartographie isotopique nanoSIMS (i.e. 75As-, 56Fe16O-, le soufre (32S-) et la matière organique (12C14N-), alors que la spéciation du soufre a été évaluée par adsorption des rayons X au seuil K du soufre (S) (XANES). Ces analyses ont permis de mettre en évidences les interactions entre les oxydes de fer naturels, la matière organique naturelle (MON) et un métalloïde toxique, l’arsenic. Nos résultats suggèrent, par colocalisation statistique des images nanoSIMS, l’existence de deux types d’interaction : (1) 12C14N-, 32S-, 56Fe16O- et 75As-, et (2) 12C14N-, 32S- et 75As-. La coexistence des formes de S oxydées et réduites, confirmées par les analyses XANES, pourrait être attribuée à la lente cinétique d’oxydation de la MON. Ainsi, ce premier volet montre qu’en plus des interactions MON, oxydes de fer et As, de possibles interactions directes entre As et NOM à travers des groupements fonctionnels soufrés (e.g. thiols) sont aussi possibles en milieu oxydé. Dans un second volet, l’effet des nano-Fe3O4 (~ 10 nm) sur la mobilité des éléments traces (ETs) et des colloïdes, dans l'horizon organominéral d’un sol naturel de ZHR, a été évaluée à l’aide de colonnes de sol. Nos résultats montrent que l’enrobage des nanoparticules semble influencer la mobilité de la MON et des ETs du sol. En effet, la mobilité des ETs semble augmenter en présence de nano-Fe3O4 nus, suggérant des associations où la MON stabiliserait les nanoparticules et augmenterait leur mobilité ainsi que celle des ETs associés<br>Nanoscience is based on changes in particle properties when their diameter is below 100 nm (ie nanoparticles, NPs). Considering the increasing use of such NPs and their discharge into the environment, the assessment of their risks to human health and the environment is a major issue. Underneath the protection of waters and soils, the surface water assessment quality is particularly important, especially in wetlands, where the toxic metals dynamic (e.g. As, Pb, Ni, Cr , Hg) is complex and depends on the redox conditions of the environment. As magnetite (nano-Fe3O4), a natural or manufactured NP, is known for its significant adsorption capacity with heavy metals, their interactions in riparian wetlands with trace metals (TMs) remain critical concerning their direct of indirect impact on trace metals (TMs) mobility. The objective of this thesis was to study the role of manufactured nano-Fe3O4 (~ 10nm) and natural iron oxides on the TMs dynamics in wetland surface waters and soils. Therefore, in a first part considering natural colloidal precipitates from reoxidation products from riparian areas (subject to redox oscillations), a spatial distribution of elements was performed using nanoSIMS isotope mapping (i.e. 75As-, 56Fe16O-, sulfur (32S-) and organic matter (12C14N-), while the sulfur speciation was evaluated X-ray adsorption at K edge of the sulfur (S) (XANES). These analyzes allowed to highlight the interactions between natural iron oxides, natural organic matter (NOM) and a toxic metalloid, As. Our results suggest, with a statistical colocalization of nanoSIMS images, the existence of two interaction types: (1) 12C14N-, 32S-, 56Fe16O- and 75As-, and (2) 12C14N-, 32S- and 75As-. The coexistence of the oxidized and reduced forms of S, confirmed by the XANES analyses might be attributed to the slow oxidation kinetic of MON. Thus, this first part shows that in addition to the known interactions between MON, iron oxides and As, a possible direct interaction between As and NOM through sulfur functional groups (e.g. thiols) are also possible in oxidized environment. In a second part, the effect of nano-Fe3O4 (~ 10 nm) on trace elements (TEs) and colloids mobility in the organomineral horizon of a natural wetland soil was assessed using soil columns. Our results show that the nanoparticles coating influences the mobility of NOM and TMs. Indeed, the TMs mobility increases in presence of naked nano-Fe3O4, suggesting associations where NOM stabilizes the nanoparticles and increase the nanoparticles and associated TMs mobility. This mechanism seems less possible with coated nano-Fe3O4 where MON blocks the coating adsorption sites and therefore the adsorption of metals
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Tessier, Erwan. "Diagnostic de la contamination sédimentaire par les métaux/métalloïdes dans la rade de Toulon et mécanismes controlant leur mobilité." Thesis, Toulon, 2012. http://www.theses.fr/2012TOUL0003/document.
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L’étude réalisée porte sur l’évaluation du niveau de contamination par les éléments traces métalliques (ETM) des sédiments de la rade de Toulon, une rade semi-fermée soumise à un fort impact anthropique. Le prélèvement de carottes d’interface en 52 points répartis sur l’intégralité de la Rade a permis d’établir une cartographie précise des caractéristiques sédimentaires et des teneurs en métaux/métalloïdes. Les résultats obtenus sur les sédiments de surface ont montré l’état de contamination significatif de la rade (en particulier en Cu, Hg, Pb, et Zn), notamment dans les zones les plus enclavées de la petite rade, où les teneurs peuvent dépasser de plusieurs ordres de grandeur les limites définies par la législation en vue d’opérations de dragage. La distribution de la contamination observée a clairement indiqué un export de la petite vers la grande rade (normalement moins exposée), probablement gouverné par des processus hydrodynamiques responsables de la remise en suspension du sédiment contaminé. Les profils sédimentaires de carottes d’interface prélevées dans des zones de contamination contrastée ont révélé la présence systématique de pics de contamination dans les 20 premiers cm. Compte tenu des taux de sédimentation déterminés, ceci démontrerait que la rade a été soumise à un épisode de multi-contaminations majeur, probablement lié aux conséquences de la 2nde guerre mondiale. L’analyse des eaux interstitielles et surnageantes (paramètres physico-chimiques, majeurs, traceurs diagénétiques et ETM) de ces carottes d’interface a permis d’étudier la mobilité des ETM dans le sédiment. Les profils obtenus apparaissent essentiellement contrôlés par des mécanismes diagénétiques et démontrent le rôle exercé par les principales phases porteuses présentes dans le sédiment (oxy-hydroxydes de Fe et de Mn, sulfures) sur la mobilité des ETM. La modélisation de ces profils a permis d’évaluer les flux diffusifs à l’interface eau sédiment, afin de déterminer l’action du sédiment, en tant que puits ou source de contamination pour la colonne d’eau. Les flux diffusifs sortant calculés apparaissent relativement faibles en comparaison des teneurs totales mesurées dans le sédiment, démontrant que la majorité des ETM est fortement immobilisée dans le sédiment.Enfin, ce travail a été complété par des expériences de remise en suspension en laboratoire et sur le terrain, visant à simuler différents scénarios possibles (tempête,trafic maritime, dragage). Dans les conditions étudiées, si pour certains ETM la remobilisation en solution est faible (ex. As, Hg), elle peut au contraire être très significative pour d’autres (ex. Cd, Cu, Pb) conduisant à une contamination non négligeable de la colonne d’eau<br>This study deals with the assessment of sediment contamination levels by trace metals in the Toulon bay, a semi-closed Mediterranean area submitted to heavy anthropogenic inputs. The sampling of interface cores in 52 points located in thewhole bay allowed establishing a precise mapping of the sedimentary characteristics and the metals/metalloids contents. The obtained results from the surface sediments revealed a significant contamination of the bay (especially for Cu, Hg, Pb and Zn), mainly in the most enclosed parts of the small bay. There, the levels may exceed by several orders of magnitude the limits concerning dredging operations defined by the French legislation. The observed contamination distribution clearly indicated an export from the small to the large bay (normally less exposed) probably governed by hydrodynamic processes, responsible for the contaminated sediment resuspension. The sedimentary profiles of interface cores sampled in contrasted contamination areas revealed the presence of systematic contamination peaks in the first 20 cm. Taking into account the calculated sedimentation rate, this would demonstrate that the Toulon bay was submitted to a strong multi-contamination, probably linked to the 2nd world war. The analysis of interstitial waters (physico-chemical parameters,major, trace metals, and diagenetic tracers) allowed studying trace metals mobility. The obtained profiles appeared mainly controlled by diagenetic mechanisms and showed the major role of the main carrier phases present in the sediments (oxyhydroxides of Fe and Mn, sulphides). The modeling of these profiles led to the determination of the diffusive fluxes at the sediment/water interface, and so, to the action of the sediment as a sink or a source of contamination for the water column.The calculated outgoing diffusive fluxes appeared relatively low in comparison to the total contents measured in the sediment, proving that the main part of the studied trace metals remains in the sediment. Finally, resuspension experiments in lab and on field were performed with the aim to simulate different possible scenarios (storm,nautical traffic, dredging). Under the studied conditions, the remobilization can be low for some trace metals (e.g. As, Hg), but it may contrariwise be quite important for others (e.g. Cd, Cu, Pb) leading to a non-negligible contamination of the water column
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Sinn, Julie A. ""I ain't no trick baby" or princess in disguise gender boundaries and female mobility in Freeway, Snow White : a tale of terror, and Ever after : a Cinderella story /." [Gainesville, Fla.] : University of Florida, 2001. http://purl.fcla.edu/fcla/etd/UFE0000353.
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Dubrous, Vincent. "Simulation en santé chez les infirmiers de sapeurs-pompiers : trace de l'erreur et pérennité des apprentissages selon le degré de réflexivité mobilisé." Thesis, Aix-Marseille, 2020. http://www.theses.fr/2020AIXM0002.
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Cette recherche est centrée sur la population des infirmiers de sapeurs-pompiers en formation continue dans le domaine de l’urgence pré hospitalière. Son objet est d’étudier la trace des erreurs réalisées lors des apprentissages en simulation et la pérennité de ces apprentissages, à moyen terme, selon le degré de réflexivité mobilisé lors du débriefing filmé, versus des apprentissages effectués sans instrumentation audio vidéo. La méthode de recherche est mixte, quantitative et qualitative.La taxonomie des erreurs initiales permet de caractériser des erreurs de processus cognitifs et des erreurs non techniques, essentiellement de leadership, de communication et d’organisation. Est également repérée l’influence des processus d’apprentissage par le stress et les émotions.Le degré de réflexivité est corrélé au type de débriefing, celui instrumenté par la vidéo étant le plus performant. Si l’influence du débriefing filmé, sur l’évitement de l’erreur initiale n’est pas statistiquement démontrée à moyen terme, les analyses qualitatives des corpus donnent à voir l’efficacité de la simulation pour la professionnalisation des infirmiers d’urgence et la limitation des récidives d’erreurs sur le terrain. Un lien de corrélation entre la formation et l’erreur autorisée est remarqué pendant le temps de débriefing.L’apprentissage est plus fécond en simulation qu’en situation réelle. La temporalité des processus réflexifs étaye l’intérêt d’une formation curriculaire.Cependant, la simulation peut engendrer des erreurs par confusion de postures, par exemple lors de jeux de rôles<br>This research focuses on nurses from fire brigades undergoing continuous training in the field of pre-hospital emergencies. The aim is to study the impacts of mistakes made during simulations and the sustainability of training, on the medium-term, depending on the degree of reflexivity gathered during debriefing, compared to the level without audio video instrumentation. The research method is mixed, quantitative and qualitative.The taxonomy of initial mistakes highlights mistakes in cognitive processing and non-technical mistakes, essentially in leadership, communication and organisation, which are consistent with literature. The influence of stress and emotions on the apprenticeship process is also listed. However, leadership reveals to be the main cause behind initial mistakes.The degree of reflexivity is correlated to the type of debriefing used, video footage proving to be the most efficient. Although the influence of filmed debriefing on the avoidance of initial mistakes is not statistically proven on the medium-term, qualitative analyses of corpora reveal the efficiency of simulation for the professionalisation of nurses working with emergencies and the limitation of repeated mistakes on the field. A link between training and permitted mistakes is observed during the debriefing period.Training is more fruitful in simulation rather than in real-life situations and the temporality of reflective processes is a favour from curriculum training. However, simulation can lead to mistakes due to posture confusion during role play.Highlighting the difficulty to take on a leader posture for a response team allows room for recommendations towards trainers
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Varrault, Gilles. "Étude cinétique de l'extraction des métaux traces des sols : application à l'évaluation de l'efficacité de techniques de réhabilitation in situ." Paris 7, 2001. http://www.theses.fr/2001PA077156.
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Pontoni, Ludovico. "Accumulation and colloidal mobilization of trace heavy metals in soil irrigated with treated wastewater." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1144/document.
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La réutilisation des eaux usées traitées pour l’irrigation est globalement acceptée et pratiquée pour faire face à la pénurie d'eau et économiser les ressources de haute qualité. Bien que cette pratique présente des avantages indéniables et contribue à un usage plus durable de l'eau douce, elle n’est pas exempt de problèmes liés à l'impact potentiel sur la qualité des sols récepteurs et sur les cultures de micropolluants contenus dans l'eau réutilisée. Parmi ces polluants, les métaux lourds (ML) en concentrations traces jouent un rôle primordial en raison de leur présence systématique dans l'eau utilisée et de leur persistance une fois libéré dans l'environnement. Le devenir des ML dans les sols peut difficilement être prédit parce que les mécanismes de mobilité à travers les sols sont extrêmement variés et liés à des phénomènes simultanés et très complexes impliquant différents équilibres chimiques. Les ML, comme beaucoup d'autres contaminants, ne sont pas seulement partagé entre la phase immobile (le sol) et les phases mobiles présentes dans l'eau. En effet, les colloïdes et les nanoparticules agissent comme une troisième phase mobile, avec leurs propres propriétés rhéologiques et des vitesses de migrations qui leur sont propres. Ce dernier aspect a été l'un des principaux objectifs d’étude de la thèse. Plusieurs essais expérimentaux ont été menés en irriguant un sol standard selon l'Organisation de coopération et de développement économiques (OCDE) avec une eau usés traités réel et / ou synthétiques, contenant des ML en concentrations traces. Pour chaque test, un sol spécifique (avec différentes teneurs en matière organique) et des eaux usées traitées de composition différente (avec différentes concentrations en métaux traces, de salinité, de la teneur en matière organique pour les eaux usées synthétiques, ou des eaux usées traitées réelles) ont été choisi afin d'évaluer les effets des conditions différentes sur le devenir global des ML. L'augmentation de la matière organique du sol de 2,5 à 10% a linéairement amélioré la mobilité des Cd, Cu et Ni avec une augmentation de la mobilité maximum de 35,6, 43,7 et 49,19% pour le Cd, Cu et Ni, respectivement. Pour la plupart des expériences, les ML ont été capturés dans la couche superficielle du sol (0,5 à 1 cm). Néanmoins, des pics de contamination ont été détectés à des profondeurs différentes dans les couches plus profondes du sol. L’étude de la composition des lixiviats montre des variations de concentrations fonction du métal étudié et des caractéristiques du sol et des eaux usées. Des pics de métaux dans le lixiviat sont apparus en même temps que la libération de la matière et / ou la libération de silicates organiques, ce qui démontre l'implication significative des colloïdes dans le transport des métaux. La concentration en sodium (20 mM) a été démontrée un impact fort sur la réduction de la mobilisation colloïdale et que plus de 95% du métal apporté a été détecté dans la couche superficielle du sol en dépit de sa teneur en matière organique. La salinité affiche donc des effets significatifs. L'irrigation avec des eaux usées traitées présentant une très haute teneur en Ca et Mg (111 et 134 mg / L, respectivement) a abouti à la libération moyenne plus élevée de silicium à partir de la matrice inorganique du sol (8,2 mg / L) par rapport à la faible salinité des eaux usées artificielle (1,9 mg / L). Par conséquent, la mobilisation ultérieure de Cd, Cu, Ni et Zn a été observée lorsque le sol a été irrigué avec des eaux usées traitées réelles. Une caractérisation spectroscopique avancée des lixiviats a été réalisée pour identifier les agrégats colloïdaux libérés par le sol dans le but d’en déterminer leur nature, leurs propriétés chimiques et leur état d'agrégation<br>Reuse of treated wastewater for agricultural purposes is worldwide accepted and practiced to face water scarcity and save high quality resources. Although such practice has undoubtable advantages and is certainly more sustainable respect to the use of fresh water, it is not exempt from severe concerns related to the potential impact on the receiving soil and on the crops of potentially harmful pollutants contained in the reused water at trace levels. Among these pollutants, trace heavy metals (HMs) play a primary role due to their spread presence in the used water and to their persistence once released in the environment. The fate of HMs in the soils can be hardly predicted as mechanisms of mobility through soils are extremely diverse and related to highly complex simultaneous phenomena and chemical equilibria. HMs, in fact, as many other contaminants, are not only partitioned between the solid immobile and the water mobile phases. Indeed, colloids and nanoparticles act as a third mobile phase, with their own rheological properties and velocity. This latter aspect has been one of the main focus of the thesis. In details the thesis describes the results of several experiments conducted irrigating the OECD standard soil with real and/or synthetic wastewater, containing HMs in trace. For each test a specific soil (e.g. varying the organic matter content) and wastewater composition (e.g. varying the metals concentration, the salinity, the organic matter content, or testing real treated wastewaters) has been chosen in order to evaluate the effects of different conditions on the overall HMs fate. The increase of soil organic matter from 2,5 to 10% linearly enhanced the mobility of Cd, Cu and Ni up to a maximum mobility increase of 35.6, 43.7 and 49.19 % for Cd, Cu and Ni, respectively. In most experiments metals accumulated in the top soil layer (0.5 - 1 cm). Nevertheless peaks of contamination were detected at different depths in the soil deeper layers and at different leaching time in the leachates depending on the metal and on the soil and wastewater characteristics. Peaks of metals in the leachate appeared simultaneously with release of organic matter and/or release of silicates, demonstrating outstanding involvement of colloids in metals transport. Sodium concentration (20mM) decidedly reduced colloidal mobilization whereas more than 95 % of the influent metal was detected in the top layer despite the soil organic matter content. Salinity displayed different effects. The irrigation with real treated wastewater with quite high content of Ca and Mg (111 and 134 mg/L, respectively) resulted in higher average release of silicon from the soil inorganic matrix (8.2 mg/L) compared to the low salinity artificial wastewater (1.9 mg/L). Consequently higher mobilization of Cd, Cu, Ni and Zn was observed when the soil was irrigated with real treated wastewater. An advanced spectroscopical characterization of the leachates was performed to identify such colloidal aggregates. The observation of 3D excitation-emission matrix demonstrated in all the leachates samples the presence of fulvic (230-450 nm ex-em fluorescence area) and humic (330-445 nm ex-em) substances. In this context, a novel analytical method was developed to quantify phenolic substances in soil matrices allowing the monitoring of humic matter migration in soil profiles. The novel method was more accurate and more precise respect to the traditional one, allowing to obtain higher recovery of total phenols in peat soil (15.5 % increase) with a decrease of the coefficient of variation (30.1% decrease). Organic water soluble colloids were extracted from the peat used to prepare the OECD standard soil and characterized. Results of size exclusion chromatography highlighted the supramolecular structure of the extracted organic matter. Such structure was further confirmed through fluorescence and 1H-NMR spectroscopy
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Amiot, Nicolas. "Design of simulation platform joigning site specific radio propagation and human mobility for localization applications." Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-00971809.
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This thesis focuses on the development of tools and methods dedicated for ultra wide band (UWB) localization systems in indoor environment. The thesis work was conducted within the European FP7 project Where2, about the cooperative localization in cellular networks. Data from a measurement campaign conduct during the project are used to validate the proposed algorithms. This thesis is divided in four parts : The first part is focused on the description of an original raytraing tool based on a graph description. In order to be compliant with the requirement of a mobile simulation, a new concept of rays signature enabling incremental computation, and a vectorized formalism for processing rays are described and implemented. The second part is focused on the indoor localization techniques, where a novel technique based on interval analysis approaches is presented and compared to alternative techniques. Advantageously using this approach, a specific processing based on an hypothesis testing method using received power observations to resolve ambiguities appearing in under determined localization problems is described. A third part describes different aspects of the dynamic platform. In particular a realistic mobility model based on ''steering behaviors'', a graph description of the network scene and an inter agents communication protocol are detailed. The fourth section uses measured data obtained from an heterogeneous measurement campaign to validate both the developed software platform and the proposed localization algorithms.
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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 de proposer un schéma cohérent des différents fractionnements isotopiques de Zn liés à son traitement métallurgique. L'existence de différents δ66Zn pour le zinc « enrichi » et « résiduel » s'avère donc un outil puissant de localisation de sources de contamination métallurgique. Ces résultats démontrent l'efficacité des isotopes stables comme traceurs de processus et de source de contamination.
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Akinyemi, Segun Ajayi. "Geochemical and mineralogical evaluation of toxic contaminants mobility in weathered coal fly ash: as a case study, Tutuka dump site, South Africa." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1226_1360593017.
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<p>The management and disposal of huge volumes of coal combustion by products such as fly ash has constituted a major challenge to the environment. In most cases due to the inadequate alternative use of coal fly ash, the discarded waste is stored in holding ponds, slag heaps, or stock piled in ash dumps. This practice has raised concerns on the prospect of inorganic metals release to the surface and groundwater in the vicinity of the ash dump. Acceptable scientific studies are lacking to determine the best ash disposal practices. Moreover, knowledge about the mobility patterns of inorganic species as a function of mineralogical association or pH susceptibility of the dry disposed ash dump under natural weathering conditions are scarce in the literature. Fundamental understanding of chemical interactions of dry disposed ash with ingressed CO2 from atmosphere, percolating rain water and brine irrigation within ash disposal sites were seen as key areas requiring investigation. The mineralogical association of inorganic species in the dry disposed ash cores can be identified and quantified. This would provide a basis for understanding of chemical weathering, mineralogical transformations or mobility patterns of these inorganic species in the dry ash disposal scenario. The current study therefore aims to provide a comprehensive characterisation of weathered dry disposed ash cores, to reveal mobility patterns of chemical species as a function of depth and age of ash, with a view to assessing the potential environmental impacts. Fifty-nine samples were taken from 3 drilled cores obtained respectively from the 1 year, 8 year and 20-year-old sections of sequentially dumped, <br>weathered, dry disposed ash in an ash dump site at Tutuka - a South African coal burning power station. The core samples were characterized using standard analytical procedures viz: X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transforms infrared (FTIR) techniques, Scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) and Acid neutralisation capacity (ANC) test. A modified sequential extraction (SE) method was used in this study. The chemical partitioning, mobility and weathering patterns in 1 year, 8 year and 20-year-old sections of the ash dump were respectively investigated using this modified sequential extraction scheme. The sequence of the extractions was as follows: (1) water soluble, (2) exchangeable, (3) carbonate, (4) iron and manganese and (5) residual. The results obtained from the 5 steps sequential extraction scheme were validated with the total metal content of the original sample using mass balance method. The distribution of major and trace elements in the different liquid fractions obtained after each step of sequential extraction of the 59 drilled core samples was determined by inductively coupled plasma mass spectrometry (ICPMS). The data generated for various ash core samples were explored for the systematic analysis of mineralogical transformation and change in ash chemistry with ageing of the ash. Furthermore, the data was analyzed to reveal the impact of ingressed CO2 from atmosphere, infiltrating rain water and brine irrigation on the chemistry of ash core samples. Major mineral phases in original ash core samples prior to extraction are quartz (SiO2) and mullite (3Al2O3·<br>2SiO2). Other minor mineral phases identified were hematite (Fe2O3), calcite (CaCO3), lime (CaO), anorthite (CaAl2Si2O8), mica (Ca (Mg, Al)3 (Al3Si) O10 (OH)2), and enstatite (Mg2Si2O6). X-ray diffraction results show significant loss of crystallinity in the older ash cores. The presence of minor phases of calcite and mica in dry disposed ash cores are attributed to reduction in the pore water pH due to hydration, carbonation and pozzolanic reactions. The X-ray diffraction technique was unable to detect Fe-oxyhydroxide phase and morealuminosilicate phases in ash core samples due to their low abundance and amorphous character. X-ray fluorescence results of the original ash core samples showed the presence of major oxides, such as SiO2, Al2O3, Fe2O3, while CaO, K2O, TiO2, Na2O, MnO, MgO, P2O5, and SO3 occur in minor concentrations. The ratio of SiO2/Al2O3 classified the original core samples prior to extraction as a silico-aluminate class F fly ash. The ternary plot of major elements in 1-year-old ash core samples was both sialic and ferrocalsialic but 8 year and 20-year-old ash core samples were sialic in chemical composition. It is noteworthy that the mass % of SiO2 varies through the depth of the core with an increase of nearly 3 %, to 58 mass % of SiO2 at a depth of 6 m in the 1-year-old core whereas in the case of the 8-year-old core a 2 % increase of SiO2 to a level of 57.5 mass % can be observed at levels between 4-8 m, showing dissolution of major components in the matrix of older ash cores.. The Na2O content of the Tutuka ash cores was low and varied between 0.6-1.1 mass % for 1-year-old ash cores to around 0.6-0.8 mass % for 8-year-old ash cores. Sodium levels were higher in 1-year-old ash cores compared to 8 year and 20-year-old ashcores. Observed trends indicate that quick weathering of the ash (within a year) leached out Na+ from the ash dump. No evidence of Na+ encapsulation even though the ash dump was brine irrigated. Thus the dry disposal ash placement method does not result in a sustainable salt sink for Na-containing species over time. The total content of each of the elements in 1 year and 20-year-old ash cores was normalised with their total content in fresh ash from same power station to show enrichment and depletion factor. Major elements such as K+, Mn showed enrichment in 1-year-old ash cores whereas Al, Si, Na+, Ti, Ca, Mg, S and Fe showed depletion due to over time erosion. Trace elements such as Cr, Sr, P, Ba, Pb, V and Zn showed enrichment but Ni, Y, Zr showed depletion attributed to over time erosion. In 20-year-old ash cores, major elements such as Al, Na+ and Mn showed enrichment while Si, K+, Fe, Mg and Ca showed depletion highlighting their mobility. Trends indicated intensive flushing of major soluble components such as buffering constituents (CaO) by percolating rain water. The 1-year-old and 20-year-old coal ash cores showed a lower pH and greater loss/depletion of the soluble buffering constituents than the 2-week-old placed ash, indicating significant chemical weathering within a year. Based <br>on ANC results the leaching behaviours of Ca, Mg, Na+, K+, Se, Cr, and Sr were found to be controlled by the pH of the leachant indicating high mobility of major soluble species in the ash cores when in contact with slightly acid rain water. Other investigated toxic metals such as As, Mo and Pb showed amphoteric behaviour with respect to the pH of the leachant. Chemical alterations and formation of transient minor secondary mineral phases was found to have a significant effect on the acid susceptibility and depletion pattern of chemical species in the core ash samples when compared to fresh ash. These ANC results correlated well with the data generated from the sequential extraction scheme. Based on sequential extraction results elements, showed noticeable mobility in the water soluble, exchangeable and carbonate fractions due to adsorption and desorption caused by variations in the pore water pH. In contrast, slight mobility of elements in the Fe and Mn, and residual fractions of dry disposed fly ashes are attributed to the co-precipitation and dissolution of minor amount of less soluble secondary phase overtime. The 1-year-old dry disposed ash cores were the least weathered among the 3 drilled ash cores. Therefore low concentration of toxic metals in older ash cores were ascribed to extensive weathering with slower release from residual mineral phases over time. Elements were found to associate with different mineral phases depending on the age or depth of the core samples showing greater heterogeneity in dispersion. For instance the average amount of total calcium in different mineral associations of 1-year-old ash cores is as follows<br>water soluble (10.2 %), exchangeable (37.04 %), carbonate (37.9 %), Fe and Mn (7.1 %) and residual (2.97 %). The amount of total Na+ in different mineral phases of 1-year-old ash cores followed this trend: water soluble (21 %), exchangeable (11.26 %), carbonate (2.6 %), Fe and Mn (4.7 %) and residual (53.9 %). The non-leachable portion of the total Na+ content (namely that contained in the residual fraction) in the 1-year-old ash core samples under conditions found in nature ranged between 5-91 %. This non-leachable portion of the Na+ showed the metastability of the mineral phases with which residual Na+ associates. Results showed older ash cores are enriched in toxic elements. Toxic elements such as As, B, Cr, Mo and Pb are enriched in the residual fraction of older ash cores. For instance As concentration in the residual fraction varied between 0.0003- 0.00043 mg kg-1 for 1-year-old ash cores to around 0.0003-0.0015 mg kg-1 for 20-year-old ash cores. This suggests that the older ash is enriched in toxic elements hence dust from the ash dump would be toxic to human health. The knowledge of mobility and ecotoxicological significance of coal fly ash is needed when considering its disposal or reuse in the environment. The mobility and ecotoxicology of inorganic metals in coal fly ash are determined by (i) mineralogical associations of inorganic species (ii) in-homogeneity in the ash dumps (iii) long and short term exposure to ingress CO2 and percolating rain water. Management issues such as inconsistent placement of ash in the dumps, poor choice of ash dump site, in-homogeneity in brine irrigation, no record of salt load put on the ash dumps and lack of proper monitoring requires improvement. The thesis provides justification for the use of the modified sequential extraction scheme as a predictive tool and could be employed in a similar research work. This thesis also proved that the dry ash disposal method was not environmental friendly in terms of overall leaching potential after significant chemical weathering. Moreover the study proved that the practice of brine co-disposal or irrigation on ash dumps is not sustainable as the ash dump did not act as a salt sink.</p>
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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) permet de proposer un schéma cohérent des différents fractionnements isotopiques de Zn liés à son traitement métallurgique. L'existence de différents d66Zn pour le zinc " enrichi " et " résiduel " s'avère donc un outil puissant de localisation de sources de contamination métallurgique. Ces résultats démontrent l'efficacité des isotopes stables comme traceurs en matière de traçage de processus et de source de contamination<br>A multi-elementary spiking method has been is developpeddeveloped in order to simultaneously quantify and caracterizecharacterize simultaneously the labile pools fraction of Cd, Zn, Ni, Cu and Pb in contaminated soils. This method is has been validated by comparison with 1) radioactive Cd spiking data,g Cd and of2) chemical extractions results. In additionFurthermore, an integrated study of Zn isotopic signatures (d66Zn) in various compartments pools of two contaminated ecosystems (zinc smelting sites of Viviez-Decazeville, S. -W. Of France and of Kempen, N. -E of Belgium) has been performed allowing the identification of various allows to assume a coherent scheme of Zn isotopic fractionations during associated to the metallurgical processes. The differents d66Zn ratio observed in between "enriched" and "residual" zinc would be a powerfull tool to identify the metallurgical contaminations origins. These results demonstrate the efficiency of stable isotopes as tracers for contamination processes and sourcescontaminations tracers
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Testiati, Eti. "Contamination de sols par des éléments traces métalliques en zone méditerranéenne côtière : études de leur mobilité et du transfert à la phytocénose." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4804/document.
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Les objectifs de cette thèse ont été de contribuer à l'évaluation des niveaux de contamination en éléments traces métalliques et métalloïdes (ETMM) des sols du site de l'ancienne fonderie de plomb de l'Escalette (sud-est de Marseille), d'en approcher les processus de transport et transfert dans l'environnement en particulier leurs mobilités dans le sol et leurs transferts aux plantes. La contribution à l'établissement d'une cartographie de la contamination sur un périmètre plus vaste que celui de l'usine (zone des Calanques) a permis de mettre clairement en évidence l'impact de cette dernière. Sur le site industriel, les formes et niveaux de contamination des sols diffèrent d'une zone à l'autre. Les sols formés en surface des crassiers se caractérisent par leurs fortes teneurs en Cu, Zn et Pb, dont les fractions mobilisables sont notables (2 à 30%), l'influence des scories est nette. Les sols prélevés à proximité de la cheminée présentent les plus fortes contaminations en Pb, Sb et As, avec de 10 à 30% de fractions mobilisables. Cette contamination est liée aux émissions anciennes via la cheminée rampante mais aussi à la dégradation de cette dernière. Le potentiel de libération des éléments As et Sb des sols de ces 2 zones conduirait à leurs stockages dans des décharges pour déchets dangereux. Les essais de solubilisation en milieu acide ont mis en évidence des risques pour la santé par ingestion concernant Pb et As. Les zones en proche périphérie de l'usine sont moins impactées mais sont néanmoins considérées comme fortement contaminées. G. alypum et R. officinalis, présentes sur le site, sont tolérantes aux ETMM et peuvent les accumuler<br>The overall objective of this thesis was to contribute to the assessment of the level of contamination by trace metals and metalloids (TMM) on the site of Escalette (a former lead smelter in southeastern Marseille). The study of TMM transfer and transport processes on this site, taking into account their mobility in the soil and their transfer to plants, was a specific objective. The mapping of TMM contamination in an extended area around the factory site (on Calanques zone) has clearly highlighted the impact of the former industry. So, on the Escalette site, forms and levels of soil contamination differ from one area to another. Soils formed on the surface of the slag deposits are characterized by high levels of Cu, Zn and Pb, whose mobilizable fractions are significant (2-30%), showing a clear influence of slag. Soils collected near a chimney creeping uphill the slope, present the highest contamination levels in Pb, Sb and As, with from 10 to 30 % of mobilizable fractions. This contamination is linked to emissions through the damaged chimney but also to the degradation of this latter. The potential release of As and Sb from the soils of these two areas requires that these soils must be disposed of in landfills for hazardous wastes and their solubilization in acid medium have highlighted the health risks by ingestion for Pb and As. On areas in near periphery of the smelter, soils are less affected but must be still considered heavily contaminated. G. alypum and R. officinalis were observed on the site. They are tolerant and can accumulate TMM. Concentrations in roots were significantly correlated with the concentrations in soils, except for Cu
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Drapeau, Clémentine. "Mesure et modélisation de la mobilité et de la spéciation des éléments majeurs et traces métalliques au sein de matrices complexes polluées en fonction du pH : application aux sédiments urbains et déchets miniers." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSET007/document.
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Les sédiments urbains et résidus minier sont deux sources de pollution potentielle pour l’environnement et plus particulièrement les eaux de surfaces ou les eaux souterraines. L’altération chimique de ces interfaces solides par contact avec une source d’acidité ou d’alcalinité via l’air ou l’eau, est susceptible de se traduire par une dissolution des phases minérales et organiques et d’induire une mobilisation des éléments majeurs et traces métalliques. Ces mécanismes sont encore mal décrits et modélisés pour ce type de matrices très complexes. Cette thèse étudie donc le potentiel de mobilisation des éléments majeurs et traces métalliques de diverses interfaces carbonaté ou non carbonaté (pour l’étude du drainage minier acide et neutre contaminé). En supplément, des interfaces minérales pures ont été utilisées pour simuler en laboratoire des assemblages de phases et identifier les mécanismes croisés impliqués dans le drainage minier acide et neutre contaminé. Toutes ces matrices ont été soumises à des tests de capacité de neutralisation acido-basique (mise en contact avec une source de protons ou d’alcalinité), avec le suivi du pH (pouvoir tampon), de la conductivité et de la mobilisation élémentaire (majeurs et éléments traces métalliques). Les données expérimentales ont été modélisées avec le logiciel de spéciation géochimique PHREEQC. La combinaison des volets d’expérimentation et de modélisation, qui a très rarement été développé sur des interfaces solides aussi complexes, a permis l’identification (i) des réactions de dissolution des phases constitutives des interfaces polluées avec les réactions de sorption impliquées dans la mobilisation de leurs éléments majeurs et traces métalliques, (ii) de la spéciation des éléments majeurs et traces métalliques dans ces interfaces et dans les solutions en équilibre avec les phases solides. Ce travail de thèse permet donc d’aboutir à une méthodologie robuste, précise et réplicable permettant une caractérisation fine de la spéciation en phase liquide et solide des polluants métalliques dans les interfaces contaminées. Cette méthodologie constitue une base cruciale pour comprendre et prédire l’évolution des matières solides contaminées (sédiments urbains et déchets miniers) en fonction des différents modes de gestion : dépollution, valorisation et recyclage<br>Urban sediments and mine tailings constitute two potential sources of pollution for the environment, especially surface water or groundwater. The chemical alteration of these solid matrices by contact with a source of acidity or alkalinity via air or water is likely to result in the dissolution of the mineral and organic phases and to induce the mobilization of majors and trace elements. These mechanisms are still poorly described and modeled for this type of very complex matrices. This thesis investigates potential for the mobilization of major and trace metals elements of various contaminated complex matrices, including an urban infiltration basin sediment and two carbonated and non-carbonated mining waste (for the study of contaminated acid mining drainage and contaminated neutral drainage). Besides, pure minerals were used to simulate phase mixture at the laboratory and identify the crossed mechanisms involved in contaminated acid and neutral mine drainage. All these matrices were subjected to acid-base neutralization capacity tests (solids put into contact with a source of protons or alkalinity), with monitoring of the pH (buffer capacity), the conductivity and the elemental release (major and trace metal elements). Experimental data were modeled with the PHREEQC geochemical speciation software. The combination of experimental and modeling approaches, which had very rarely been developed on such complex solid matrices, allowed the identification of (i) the dissolution reactions of the constitutive phases of the polluted matrices with the sorption reactions involved in the mobilization of their major and trace metal elements, (ii) the speciation of the major and trace metal elements in these matrices and in solution in equilibrium with the solid phases. This thesis, therefore, leads to a robust, precise and replicable methodology allowing a fine characterization of liquid and solid phase speciation of metallic pollutants in contaminated matrices. This methodology constitutes a crucial basis for understanding and predicting the evolution of contaminated solids (urban sediments and mining waste) according to different management methods: decontamination, recovery, and recycling
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Merrot, Pauline. "Géochimie, spéciation et mobilité des éléments traces métalliques (Fe, Ni, Cr et Mn) au sein des sédiments du lagon de Nouvelle-Calédonie." Electronic Thesis or Diss., Sorbonne université, 2019. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2019SORUS551.pdf.
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La Nouvelle-Calédonie est formée sur 33% de son territoire de roches ultrabasiques enrichies en éléments traces métalliques (ETM) (Fe, Ni, Cr, Co et Mn). L’érosion de ces massifs représente une source importante de ces ETM vers le lagon, partiellement inscrit au patrimoine mondial par l’UNESCO pour sa biodiversité. La compréhension des cycles géochimiques de ces éléments toxiques apparaît donc essentielle pour évaluer les impacts possibles sur la biodiversité de cet écosystème. La spectroscopie d’absorption des rayons X a montré que la contribution des sulfures de fer est très faible, Ni et Fe sont portés par la goethite et les argiles. Ces derniers étant la phase majeure de ces deux éléments ont été identifiés comme du chrysotile, et des greens clays : une smectite (nontronite), un mica (glauconite) et une serpentine de type greenalite/berthierine. Le cycle des argiles joue donc un rôle majeur dans le cycle de Fe et de Ni mais aussi de Mn et dans une moindre mesure de Cr. La spéciation de Mn se partage entre les argiles et les carbonates alors que Cr est surtout porté par la goethite et la chromite hérité des massifs et en dernier par les argiles. Il est important de noter que Cr se trouve sous sa forme réduite correspondant à sa forme la moins toxique. L’absence de Cr(VI) est liée à l’absence des oxydes de Mn dans les sédiments, permettant de ne pas oxyder Cr(III) en Cr(VI). Enfin, les extractions chimiques montrent une biodisponibilité relativement faible de ces métaux à l’exception de Mn impliquant un piégeage efficace, limitant ainsi les impacts sur l’environnement même si les concentrations extraites sont loin d’être négligeables pour la biodiversité du lagon<br>New Caledonia is covered on 33% of ultramafic rocks enriched in trace metals elements (Fe, Ni, Cr, Mn and Co). The erosion of these massifs represents an important source of these trace metals towards the lagoon, partially registered on the World List Heritage by UNESCO for its biodiversity. Understanding the geochemical cycle of these toxic trace metals is essential to evaluate the potential impacts on the biodiversity of this ecosystem. X-ray absorption spectroscopy (XAS) has shown that the contribution of iron sulfides is low, Ni and Fe are bearing by goethite and clays. These latter minerals representing the major phase for the Fe and Ni speciation were identified as chrysotile and green clays: a smectite (nontronite), a mica (glauconite) and a serpentine like a greenalite/berthierine. The clay minerals cycle and the green clay plays a major role in the Fe and Ni cycle, but also in Mn and to a lesser extent in the Cr cycles. The Mn speciation is shared by the clay minerals and the carbonates species whereas Cr is bearing by goethite and chromite inherited of laterite and in lesser extent by clay minerals. Cr is totally present under the reduced form which is the less toxic form. This absence of Cr(VI) is linked to the absence of Mn oxides in sediments avoiding the oxidation of Cr(III) to Cr(VI) and thus limits the impact on the environment. Finally, the chemical extractions of these metals show a relatively low bioavailability of trace metals except for Mn implying an effective long-term trapping for trace metals and thus limiting the environmental impacts even if the concentrations extracted are not negligible and can be threaten the biodiversity of the lagoon
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Schramm, Kenneth Edward. "The medium tactical vehicle replacement program-an analysis of a multi-service office." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Jun%5FSchramm.pdf.
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Li, Yi. "Dual Mobile Robot: Adaptable Mobility System." Thesis, 2012. http://hdl.handle.net/1807/65481.
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This thesis presents an adaptive and reconfigurable mobile robot: the Dual Mobile Robot (DMR). It is driven by two adaptive track-wheel driving modules that combine wheels and tracks to allow real-time interchangeability according to terrain condition. The DMR can automatically convert from a wheel-based robot into a track-based robot by rotating the track-wheel driving modules by 90 degrees, either only tracks or wheels contact with the ground without any interference. It can be driven as a wheel-based robot when operating over a paved road to achieve higher speed and low energy consumption, and as a track-based robot over uneven terrain. In addition, unlike most state-of-the-art mobile robot designs that have an integrated architecture, this design provides a modular architecture which allows modifications and upgrades to be performed via simple replacements or local changes of modules.
To establish the modular architecture, this research utilized a unique design paradigm, “Design for product adaptability”. A function-based design process for product adaptability has been conducted in the conceptual design stage. By following the design process, two types of design alternatives of the DMR have been created. After the best product configuration was chosen through evaluation and prioritization, the selected configuration has been implemented by detail design.
The DMR prototype was developed and tested to demonstrate its adaptability and advanced mobility functions in real-world environments. The experimental results successfully validated the hypothesis of the proposed robot with its track-wheel interchangeable ability, significantly exceeding the capability of other existing systems.
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Pereira, Inês Correia. "How much data is enough to track tourists? The tradeoff between data granularity and storage costs." Master's thesis, 2020. http://hdl.handle.net/10362/106282.
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Dissertation presented as the partial requirement for obtaining a Master's degree in Information Management, specialization in Knowledge Management and Business Intelligence<br>In the increasingly technology-dependent world, data is one of the key strategic resources for organizations. Often, the challenge that many decision-makers face is to determine which data and how much to collect, and what needs to be kept in their data storage. The challenge is to preserve enough information to inform decisions but doing so without overly high costs of storage and data processing cost. In this thesis, this challenge is studied in the context of a collection of mobile signaling data for studying tourists’ behavioral patterns. Given the number of mobile phones in use, and frequency of their interaction with network infrastructure and location reporting, mobile data sets represent a rich source of information for mobility studies. The objective of this research is to analyze to what extent can individual trajectories be reconstructed if only a fraction of the original location data is preserved, providing insights about the tradeoff between the volume of data available and the accuracy of reconstructed paths. To achieve this, a signaling data of 277,093 anonymized foreign travelers is sampled with different sampling rates, and the full trajectories are reconstructed, using the last seen, linear, and cubic interpolations completion methods. The results of the comparison are discussed from the perspective of data management and implications on the research, especially the results of research with lower time-density mobile phone data.
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Noack, Angela Gai. "Mobility of colloids in soils / by Angela Gai Noack." 2002. http://hdl.handle.net/2440/21934.
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"November 2002.<br>Includes bibliographical references (leaves 258-275)<br>xxi, 275 leaves, [8 p.] : ill. (some col.), plates (col.) ; 30 cm.<br>Title page, contents and abstract only. The complete thesis in print form is available from the University Library.<br>Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, 2003
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Noack, Angela Gai. "Mobility of colloids in soils / by Angela Gai Noack." Thesis, 2002. http://hdl.handle.net/2440/21934.
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"November 2002.<br>Includes bibliographical references (leaves 258-275)<br>xxi, 275 leaves, [8 p.] : ill. (some col.), plates (col.) ; 30 cm.<br>Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, 2003