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Kartezhnikova, Maria. "Hydraulic impacts of hydrokinetic energy extraction in rivers." Thesis, University of Alaska Anchorage, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1550170.
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A simple technique to estimate the hydraulic impacts associated with the deployment of hydrokinetic (HK) devices is introduced. This technique involves representing HK devices with an enhanced bottom roughness. The enhanced bottom roughness is found to be a function of Manning roughness, slope, and water depth of the natural channel as well as device efficiency, blockage ratio, and density of device deployment. This approach was developed using a theoretical relationship between power extracted to power dissipated, and assuming a simple rectangular channel cross-section and uniform distribution of devices. Once the effective bottom roughness is determined, it can be used to determine the hydraulic impact of arbitrary device configurations and flow situations. The enhanced bottom roughness approach was compared to an alternative method of determining the affects of hydrokinetic energy extraction (SNL-EFDC). Both methods were in good agreement. Capabilities and limitations of determining hydraulic impacts by enhanced bottom roughness approach are demonstrated by site-specific simulation for the Tanana site.
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Muñoa, Capron-Manieux Gorka. "The impact of oil extraction on tropical rainforests: A view from space." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/671734.
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L’augment de la demanda i consum mundial de petroli està estimulant la necessitat d’accedir a noves i cada vegada més remotes reserves d’hidrocarburs situades als boscos tropicals (Butt et al., 2013), atès que les reserves mundials de gas i petroli es superposen amb el 30% dels boscos tropicals, sent l’Amazònia la selva tropical amb major percentatge (39,4%) d’aquesta superposició (Orta-Martínez et al., 2018). Els impactes provocats per 50 anys d’activitat petroliera a l’Amazònia norperuana han causat greus danys en els ecosistemes i la salut de les persones. En aquest sentit, urgeix trobar nous mecanismes de monitorització a gran escala capaços de detectar i quantificar els impactes generats per aquesta indústria en àrees aïllades de difícil accés. La teledetecció, capaç de realitzar seguiments a escala regional, estatal i fins i tot global, pot suposar una alternativa eficaç i econòmicament viable. En aquest context, l’objectiu general de la tesi és identificar i quantificar els impactes produïts per l’activitat petroliera sobre els boscos tropicals humits mitjançant tècniques de teledetecció, dividits en: 1) identificar i quantificar la desforestació i la pertorbació provocats per l’activitat petroliera; 2) identificar els vessaments de cru; 3) desenvolupar un mètode per a la detecció d’àrees que històricament han estat contaminades a causa de la descàrrega directa d’hidrocarburs i aigües de producció. Amb aquest objectiu, s’han dut a terme tres estudis en els boscos tropicals humits de l’Amazònia norperuana. Aquests estudis s’han basat en l’anàlisi de sèries temporals d’imatges de satèl·lit, per tal d’observar els canvis en les respostes espectrals provocats per aquests impactes. Així, s’ha utilitzat una sèrie temporal d’11 imatges Landsat dels anys 1986-2005 per fer el seguiment de la desforestació a través de l’evolució de l’NDVI, i de la pertorbació de bosc, a través del mètode Carnegie Landsat Analysis System lite (Asner et al., 2009), en el lot petrolier 1AB/192. A través de 172 imatges de SAR del Sentinel 1, s’ha dut a terme una anàlisi de tres vessaments de cru i s’han desenvolupat 4 índexs de detecció de vessaments i un mètode basat en classificacions ISODATA. Finalment, s’han desenvolupat tres índexs per a la detecció de les àrees contaminades per hidrocarburs, basats en l’especificitat de la resposta espectral del petroli en certes zones de l’infraroig, i estudiar així, la seva evolució durant els anys 1985 i 2007. Els resultats obtinguts indiquen que 1) pràcticament la meitat de la desforestació i pertorbació provocada per l’activitat extractiva de petroli en els boscos tropicals es deu a la construcció i manteniment de les carreteres; 2) Els índexs proposats per a la detecció d’àrees contaminades per hidrocarburs en boscos tropicals humits resulten efectius, sobretot si es disposa d’ informació georeferenciada de la infraestructura petroliera existent, per limitar l’anàlisi a determinades zones. En aquests casos, l’índex menys restrictiu dels tres presentats, és capaç de detectar al voltant del 20-40% dels píxels contaminats, amb un percentatge d’encert superior al 90%. Com a conseqüència, es recomana: - La no explotació dels jaciments petroliers situats en els boscos tropicals humits per tractar-se de centres d’alta biodiversitat i albergar un gran nombre de comunitats indígenes, algunes d’elles vivint en aïllament voluntari. - Si no, la implementació de mètodes offshore-inland, és a dir, l’ús d’operacions que no requereixin la construcció de carreteres. - El desenvolupament d’una metodologia eficaç per a la detecció dels abocaments de petroli en boscos tropicals humits, que permeti la creació d’un sistema de monitorització en temps gairebé real (NRTM) per detectar-los.El aumento de la demanda y consumo mundial de petróleo está estimulando la necesidad de acceder a nuevas y cada vez más remotas reservas de hidrocarburos situadas en los bosques tropicales (Butt et al., 2013), ya que las reservas mundiales de gas y petróleo se superponen con el 30% de los bosques tropicales, siendo la Amazonía la selva tropical con mayor porcentaje (39,4%) de dicha superposición (Orta-Martínez et al., 2018). Los impactos provocados por 50 años de actividad petrolera en la Amazonía norperuana han causado graves daños en los ecosistemas y la salud de las personas. En este sentido, urge encontrar nuevos mecanismos de monitoreo a gran escala capaces de detectar y cuantificar los impactos generados por esta industria en áreas aisladas de difícil acceso. La teledetección, capaz de realizar seguimientos a nivel regional, estatal e incluso global, puede suponer una alternativa eficaz y económicamente viable. En este contexto, el objetivo general de la tesis es identificar y cuantificar los impactos producidos por la actividad petrolera sobre los bosques tropicales húmedos mediante técnicas de teledetección, divididos en: 1) identificar y cuantificar la deforestación y la perturbación provocados por la actividad petrolera; 2) identificar los vertidos de crudo; 3) desarrollar un método para detección de áreas que históricamente han sido contaminadas a causa de la descarga directa de hidrocarburos y aguas de producción. Para ello, se han llevado a cabo tres estudios en los bosques tropicales húmedos de la Amazonía norperuana. Estos estudios se han basado en el análisis de series temporales de imágenes de satélite, a fin de observar los cambios en las respuestas espectrales provocados por dichos impactos. Así, se ha utilizado una serie temporal de 11 imágenes Landsat de los años 1986-2005 para realizar el seguimiento de la deforestación a través de la evolución del NDVI, y de la perturbación del bosque, a través del método Carnegie Landsat Analysis System-lite (Asner et al., 2009), en lote petrolero 1AB/192. A través de 172 imágenes de SAR del Sentinel 1, se ha llevado a cabo un análisis de tres vertidos de crudo y se han desarrollado 4 índices de detección de vertidos y un método basado en clasificaciones ISODATA. Finalmente, se han desarrollado tres índices para la detección de las áreas contaminadas por hidrocarburos, basados en la especificidad de la respuesta espectral del petróleo en ciertas zonas del infrarrojo, y estudiar así, su evolución durante los años 1985 y 2007. Los resultados obtenidos indican que 1) prácticamente la mitad de la deforestación y perturbación provocada por la actividad extractiva de petróleo en los bosques tropicales se debe a la construcción y mantenimiento de las carreteras; 2) Los índices propuestos para la detección de áreas contaminadas por hidrocarburos en bosques tropicales húmedos resultan efectivos, sobre todo si se dispone información georeferenciada de la infraestructura petrolera existente para limitar el análisis a determinadas zonas. En estos casos, el índice menos restrictivo de los tres presentados, es capaz de detectar entorno al 20-40% de los píxeles contaminados, con un porcentaje de acierto superior al 90%. Como consecuencia, se recomienda: - la no explotación de los yacimientos petroleros situados en los bosques tropicales húmedos por tratarse de centros de alta biodiversidad y albergar un gran número de comunidades indígenas, algunas de ellas viviendo en aislamiento voluntario. - En su defecto, la implementación de métodos offshore-inland, es decir, el uso de operaciones que no requieran la construcción de carreteras. - El desarrollo de una metodología eficaz para la detección de los vertidos de petróleo en bosques tropicales húmedos, que permita la creación de un sistema de monitoreo en tiempo casi real (NRTM) para detectarlos.
ncreasing global oil demand and consumption is stimulating the need to access to new and more and more remote hydrocarbon reserves located in tropical rainforests (Butt et al., 2013), for the reason that world oil and gas reserves overlap with 30% of them, with the Amazon being the one with the highest percentage (39.4%) of this overlap (Orta-Martínez et al., 2018). As a result of 50 years of oil activity in the remote North Peruvian Amazon, the impacts produced by the oil companies have caused serious damages to ecosystems and people’s health. In this sense, there is an urgent need to develop new large-scale monitoring mechanisms able to detecting and quantifying the impacts generated by the extractive oil industry in isolated areas that are difficult to access. Remote sensing, capable of monitoring at the regional, state and even global scale, can be an efficient and economically viable alternative. In this context, the central aim of this thesis was to identify and quantify the impacts produced by oil activity on tropical rainforests through remote sensing techniques, distinguishing between: 1) identify and quantify deforestation and forest disturbance caused by oil activity; 2) identify oil spills caused by oil extraction industry; 3) develop a method for detecting areas that have historically been contaminated due to the direct discharge of hydrocarbons and production waters. For this purpose, three researches were carried out in tropical rainforests of the region of Loreto, in Northern Peruvian Amazon. These studies were based on the analysis of long time series of images from different satellites, in order to observe changes in spectral responses caused by oil impacts. Thus, a time series of 11 Landsat images between 1986 and 2005 were used to monitor deforestation through the evolution of the NDVI, and forest disturbance, using the Carnegie Landsat Analysis System - Lite (CLASlite) approach (Asner et al. 2009), in the oil block 192 (previously 1AB). Further, 172 Synthetic Aperture Radar (SAR) images from Sentinel 1 were used to analyse three oil spills caused by leaks in pipelines, and develop 4 oil spill detection indices and an additional methodology based on unsupervised ISODATA clustering classification. Finally, 18 multispectral Landsat 5TM images were used to develop three indices to detect oil-polluted areas, based on the specificity of the spectral response of oil in certain infrared areas. Results were used to study the evolution of these oil-covered areas between 1985-2007. The results indicate that 1) almost half of the deforestation caused by oil extraction in tropical rainforests is due to construction and maintenance of oil roads, which are also the infrastructures that cause a greater forest disturbance, edge effect and habitat fragmentation. 2) Proposed indices for the detection of oil-polluted areas on tropical rainforests are effective, especially if georeferenced information on the existing oil infrastructure is available to limit the analysis to a buffer from these infrastructures. In these cases, the least restrictive index can detect around 20-40% of the pixels covered by oil, with a success rate higher than 90%. As a consequence of these findings, it is recommended: - The non-exploitation of oil fields located in the tropical rainforests due to high impacts caused by oil extraction activity in centers of high biodiversity and cultural richness, with a large number of indigenous communities, some of them living in voluntary isolation. - Failing that, the implementation of offshore-inland methods, that is, the use of operations that do not require any road construction. The development of an effective methodology for the detection of oil spills in tropical rainforests, which allows creating a near-real-time monitoring system (NRTM) to detect them.
Universitat Autònoma de Barcelona. Programa de Doctorat en Ciència i Tecnologia Ambientals
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Hall, Adelyn N. "Socioeconomic Impacts of Natural Gas Extraction in Bradford County, PA." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1427979892.
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Walker, Clare. "Modelling the hydrological impacts of mechanised peat extraction on an upland blanket bog." Thesis, University of Huddersfield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327184.
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Pitkin, Julia. "Oil, Oil, Everywhere: Environmental and Human Impacts of Oil Extraction in the Niger Delta." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/pomona_theses/88.
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Oil extraction in Nigeria has caused extensive environmental degradation and health problems in many Nigerian communities, particularly in the ecologically sensitive Niger Delta where nearly all of the oil extraction takes place. The reasons for this are complex and have roots in Nigeria’s colonial past. The Nigerian economy is largely reliant on its petroleum resources which, in conjunction with governmental corruption and high international demand for Nigerian oil, has created a system where environmental externalities are largely ignored. Multinational oil companies with little stake in the development and environment of Nigeria are responsible for most of the extraction projects and subsequent environmental damage. However, the Nigerian federal government has failed to effectively regulate these projects. Communities in the Niger Delta bear nearly all of the environmental burden of oil extraction, but see very little of the economic benefits.
The main environmental impacts of oil extraction are oil spills, land use change, and gas flaring. Oil spills are very common in the Niger Delta. Cleanup efforts are often inadequate, resulting in loss of delicate ecosystems as well as fisheries and farmland. Large tracts of rainforest and mangrove ecosystems have been cleared or degraded by the oil extraction process. Nigeria flares more gas per barrel of oil extracted than any other country in the world, contributing to global warming and creating serious health hazards for communities located near gas flares.
Diversification of the Nigerian economy would help to alleviate many of the factors that lead to environmental degradation, including the dependence of the government on oil revenues, high unemployment, and rampant oil theft. Curbing government corruption is also vital to effective regulation of oil extraction. International consumers can help Nigeria head towards a less petroleum-driven future through an increased awareness of the origins of their oil and pressure on the Nigerian federal government and the multinational oil companies to extract oil more conscientiously or even to discontinue oil extraction. But most importantly, the solution to Nigeria’s economic concerns must ultimately come from Nigerians as international influence has been a major contributor to the environmental degradation in the first place.
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Anderson, Emily. "States of extraction : impacts of taxation on statebuilding in Angola and Mozambique, 1975-2013." Thesis, London School of Economics and Political Science (University of London), 2014. http://etheses.lse.ac.uk/3071/.
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This PhD investigates the impacts of taxation on state capacity and accountability through comparative case studies of Angola and Mozambique between 1975 and 2013. Extremes of violence and economic dependency dominate the postcolonial histories of Angola and Mozambique. These cases provide an ideal setting for comparative analysis of how civil war and single resource dependence influence the links between taxation and statebuilding. The thesis demonstrates, in contrast to bellicist notions, that civil war did not strengthen the tax systems or create stronger states. Rather, transitions from the colonial capitalist regimes to socialism and then towards market capitalism, as well as the availability of autonomous income sources, were the central drivers of change in extractive processes. The research establishes taxation as both a critical explanation for development trajectories and a reflection of state capacity and accountability. Existing research on taxation and statebuilding in contemporary developing countries tends to treat tax as a catalyst for democracy, but I find that it provides political regimes with an equally powerful tool to expand power through neopatrimonial networks and consolidate control over the state. Analysis of the case studies concludes that, driven by extraverted elite accumulation strategies, vast oil resources in Angola and large-scale foreign aid in Mozambique worked similarly to disconnect state finances from society and undermine the potential links between revenue collection and redistribution, thereby reducing the possibility of enhanced state capacity or accountability.
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Cochrane, Nicholas J. K. "Programmatic extraction of information from unstructured clinical data and the assessment of potential impacts on epidemiological research." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/30582/.
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Background For epidemiological research purposes structured data provide identifiable and immediate access to the information that has been recorded, however, many quantitative recordings in electronic medical records are unstructured. This means researchers have to manually identify and extract information of interest. This is costly in terms of time and money and with access to larger amounts of electronically stored data this approach is becoming increasingly impractical. Method Two programmatic methods were developed to extract and classify numeric quantities and identify attributes from unstructured dosage instructions and clinical comments from The Health Improvement Network (THIN) database. Both methods are based on frequently occurring patterns of recording from which models were formed. Dosage instructions: Automated coding was achieved through the interpretation of a representative set of language phrases with identifiable traits. The dosage data table was automatically recoded and assessed for accuracy and coverage of a daily dosage value, then assessed in the context of 146 commonly prescribed medications. Clinical comments: Automated coding was achieved through the identification of a representative set of text and/or Read code qualifications. The model was initially trained on THIN data for a wide range of numeric health indicators, then tested for generalizability using comments from an alternative source and assessed for accuracy, sensitivity, and specificity using a subset of 12 commonly recorded health indicators. Results Dosage instructions: The coverage of a daily dosage value within the dosage data table was increased from 42.1% to 84.8% coverage with an accuracy of 84.6%. For the 146 medications assessed, on a per-unique-instruction basis, the coverage was 79.7% on average with an accuracy of 95.4%. On an all-recorded-instructions basis the weighted coverage was 65.9% on average with an accuracy of 99.3%. Clinical comments: For all 12 of the health indicators assessed the automated extraction achieved a specificity of >98% and an accuracy of >99%. The sensitivity was >96% for 8 of the indicators and between 52-88% for the other indicators. Conclusion Dosage instructions: The automated coding has improved the quantitative and qualitative summary for dosage instructions within THIN resulting in a substantial increase in the quantity of data available for pharmaco-epidemiological research. Clinical comments: The sensitivity of the extraction method is dependent on the consistency of recording patterns, which in turn was dependent on the ability to identify the differing patterns of qualification during training.
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Jeannes, Deon Bruce. "A survey of the legal framework governing the water impacts of proposed shale gas extraction in the Karoo." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/15164.
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It is estimated that South Africa has the eighth largest resources of shale gas reserves in the world. It is reported that shale gas extraction can have important benefits which include economic growth, poverty alleviation, carbon emission reduction and most significantly alleviate the current energy shortage. However the proposed extraction of shale gas using hydraulic fracturing requires large amounts of water and many hazardous chemicals which also risks water resource pollution. This can add to water stress and conflict because the Karoo is a semi-arid, water-deficient and drought prone region. Since the extraction thereof is a relatively new technology in South Africa there is a need to determine if the current regulatory and institutional framework in South Africa will be adequate to meet the demands posed by this potentially game-changing enterprise. This minor dissertation outlines the regulatory framework regarding both the water quality and quantity in the shale gas extraction process. It recommends that while there are some regulatory building blocks in place, many gaps exist. It will recommend that an inter-departmental co-operative steering committee is established to address the many overlapping responsibilities and at times contradicting requirements.
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Kefa, Christopher Amutabi. "Assessing the Impacts of Bioenergy Extraction and Human Land Use of the Biodiversity of Kakamega Tropical Rainforest, Kenya." Bowling Green State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1465254368.
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Fleming, Ruven C. "Shale gas extraction in Europe and Germany : the impacts of environmental protection and energy security on emerging regulations." Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=228565.
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Shale gas extraction is a technology that is recently arriving in Europe and Germany. The technology brings about a considerable amount of potential environmental threats, but the extraction of shale gas also promises energy security rewards. When the European and German systems for energy and environmental regulation were developed, shale gas extraction did not exist as a technical possibility. Both systems are, hence, not entirely adapted to this technology. This work highlights different ways in which the European and German legislator could act to close existing gaps in their regulatory systems. This could mainly be done by supplementing the existing system with new, shale gas specific regulations. These regulations should be summarized in a new-build shale gas law. The current work tracks the different stages of development of such a new shale gas law, starting from the level of rather abstract constitutional objectives, which translate into clearer defined environmental principles, which in turn translate into a concrete law. Experience from other European states with the legal handling of shale gas extraction teaches that there are essentially two different orientations for such a new-build shale gas law. One is the adoption of a prohibitive moratorium and the other is the implementation of a cautious, but permissive shale gas law. This work`s original contribution to knowledge is the insight that constitutional pre-settings on the interplay of environmental protection with energy security make a cautious, but permissive shale gas law a measure that is legally sounder than a shale gas moratorium. Legally sound, in this context, means complying, to the greatest extent possible, with the applicable constitutional and quasi-constitutional objectives. A shale gas moratorium only serves one purpose, environmental protection, and does not take sufficient account of the energy security objective. A shale gas moratorium only serves one purpose, environmental protection, and does not take sufficient account of the energy security objective. A cautious, but permissive shale gas law, by contrast, possesses the ability to reconcile the competing interests of environmental protection and energy security, which makes it more resilient to judicial review than a moratorium. Having said that, it must be emphasised that shale gas regulation is ultimately a political decision and the legislator is allowed to pick either of the described solutions. This work merely describes which solution is the legally soundest in the sense defined above. To sum up, results from this study will extent what is currently known about the constitutional pre-conditions for the development of shale gas regulation. It highlight that constitutional objectives have a significant impact on the shape of energy regulation.
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Lemery, Emmanuelle. "Structure et physicochimie des tensioactifs, leurs impacts sur la toxicité cutanée et la fonction barrière." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10044/document.
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Crèmes, shampooings, savons, gels douche, ces produits cosmétiques quotidiennement utilisés, ont en commun la présence d'une matière première essentielle à leur formulation, à savoir le tensioactif ou émulsionnant. Ces molécules sont donc fréquemment en contact avec la peau. En effet, de par sa structure amphiphile particulière, le tensioactif aide à la stabilisation des émulsions, permet la formation de mousse et apporte les propriétés détergentes des produits cosmétiques nettoyants, en solubilisant les corps gras présents en surface. Ces molécules peuvent également interagir avec les composants de la peau. Une des premières preuves évidentes de l'interaction des tensioactifs avec la peau est l'observation des signes cliniques suite à l'exposition prolongée ou chronique à des formules riches en tensioactifs. Ces molécules sont maintenant connues pour engendrer des dermatites de contact d'irritation et font l'objet d'un véritable problème de santé publique concernant les maladies professionnelles aux détergents. Cependant, devant la multitude de tensioactifs présents sur le marché, les mécanismes d'action des tensioactifs sur la peau sont encore mal connus, surtout pour les tensioactifs non ioniques, très utilisés dans les produits de soin et souvent considérés comme non toxiques. Le sodium lauryl sulfate, tensioactif anionique reste à ce jour, la molécule modèle couramment étudiée. La toxicité cutanée est le plus souvent reliée à l'interaction du tensioactif avec les protéines, molécules chargées. De ce fait, les tensioactifs ioniques sont considérés comme étant les plus toxiques pour la peau. De plus, la forme monomérique du tensioactif est décrite comme l'entité responsable de la toxicité cutanée, s'insérant plus facilement dans la bicouche lipidique et pouvant ainsi pénétrer plus facilement dans la peau que sous la forme de micelles. La toxicité du tensioactif est donc également reliée à sa concentration micellaire critique. L'objectif de ce projet de recherche était d'approfondir les connaissances sur différentes propriétés physicochimiques de nombreuses classes de tensioactifs, afin de mieux comprendre leurs interactions ainsi que leurs effets sur la peau. Plusieurs niveaux d'études ont été développés. Après une analyse physicochimique des tensioactifs détaillée, des mesures in vitro ont permis d'évaluer l'effet du tensioactif sur la toxicité cutanée. L'étude portant sur la fonction barrière de la peau (propriétés de surface/détergence, organisation de la matrice lipidique et évaluation de l'extraction lipidique) a été menée via des expérimentations ex vivo. Nos études ont montré une toxicité notable de certains tensioactifs non ioniques et a contrario certains tensioactifs ioniques se sont révélés parfaitement bien tolérés. Les paramètres soulignés dans la littérature tels que la CMC et la charge des tensioactifs ont été remis en question. Plusieurs explications ont été mises en avant considérant l'organisation du tensioactif dans l'eau et son comportement vis-a-vis de la fonction barrière cutanée apportant ainsi de nouvelles pistes pour une meilleure compréhension de l'effet du tensioactif sur la peau. De plus La toxicité des tensioactifs a pu être reliée à un des trois niveaux de perturbation de la barrière cutanée: la désorganisation de la matrice lipidiqueCreams, shampoos, soaps, shower gels, these cosmetics daily used, have in common the presence of a raw material essential to their formulation, namely the surfactant or emulsifier. These molecules are therefore frequently in contact with the skin. Indeed, because of its particular amphiphilic structure, the surfactant helps the stabilization of emulsions, allows the formation of foam and provides the detergent properties of cleansing cosmetic products, by solubilizing the fatty substances present on the surface. These molecules can also interact with the components of the skin. One of the first obvious evidence of the interaction of surfactants with the skin is the observation of clinical signs following prolonged or chronic exposure to surfactant-rich formulas. These molecules are now known to cause irritant contact dermatitis and are the subject of a real public health problem regarding professional detergent diseases. However, considering the multitude of surfactants on the market, the mechanisms of action of surfactants on the skin are still poorly known, especially for nonionic surfactants, widely used in skincare products and often considered non-toxic. Sodium lauryl sulfate, anionic surfactant remains to this day, the model molecule currently studied. The cutaneous toxicity is most often related to the interaction of the surfactant with the proteins, charged molecules. As a result, ionic surfactants are considered to be the most toxic to the skin. In addition, the monomeric form of the surfactant is described as the entity responsible for cutaneous toxicity, fitting more easily into the lipid bilayer and thus able to penetrate the skin more easily than in the form of micelles. The toxicity of the surfactant is therefore also related to its critical micelle concentration. . The objective of this research project was to expand knowledge on different physicochemical properties of many classes of surfactants, to better understand their interactions and their effects on the skin. Several levels of studies have been developed. After detailed physicochemical analysis of the surfactants, in vitro measurements were used to evaluate the effect of the surfactant on skin toxicity. The study on the skin barrier function (surface properties / detergency, lipid matrix organization and evaluation of lipid extraction) was conducted via ex vivo experiments. Our studies have shown significant toxicity of some nonionic surfactants and conversely some ionic surfactants have been found to be perfectly well tolerated. Parameters highlighted in the literature such as CMC and surfactant charges have been questioned. Several explanations were put forward considering the organization of the surfactant in the water and its behavior on the skin barrier function thus bringing new tracks for a better understanding of the effect of the surfactant on the skin. In addition, the toxicity of the surfactants could be related to one of the three levels of disruption of the cutaneous barrier: the disorganization of the lipid matrix
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Turmel-Courchesne, Laurence. "Remouillage d'un grand fen continental après extraction de tourbe horticole : impacts sur les échanges de carbone et la végétation." Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/35859.
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Tableau d'honneur de la FÉSPLes tourbières jouent un rôle important dans le cycle du carbone à l’échelle de la planète, principalement par la captation de dioxyde de carbone (CO₂) et l’accumulation de carbone dans la tourbe et par de considérables émissions de méthane (CH₄). Les activités d’extraction de tourbe horticole causent la dégradation des tourbières qui fournissent des services écologiques, dont la régulation du climat. Une méthode de restauration significative, robuste et efficace a été développée pour les tourbières acides dominées par les sphaignes. Il arrive toutefois que les conditions physico-chimiques de la tourbe résiduelle après extraction soient caractéristiques des tourbières minérotrophes (fens). Lorsqu’appliquée dans un contexte de restauration de fens, la méthode de restauration par transfert de la strate muscinale s’est avérée peu efficace pour le retour des espèces vasculaires et muscinales typiques des fens. Dans certains contextes, la technique de remouillage sans autre action de restauration pourrait s’avérer efficace pour restaurer les fens post-extraction. Le but de cette étude est d’évaluer l’efficacité du remouillage à rétablir la végétation caractéristique des fens, ainsi que leur fonction de séquestration du carbone, et cela une et dix saisons de croissance après remouillage. Le site à l’étude se trouve dans le sud-est du Manitoba, au Canada. Les données ont été récoltées durant les étés 2016 et 2017. Le remouillage peut rapidement mener à des échanges de CO₂ typiques des tourbières naturelles. Le remouillage a résulté en des écosystèmes dominés par des espèces vasculaires typiques des milieux humides et des tourbières minérotrophes et ombrotrophes. Dix saisons de croissance après remouillage, un tapis discontinu de mousses typiques des tourbières minérotrophes s’est rétabli. Le remouillage peut être utilisé de manière efficace pour la restauration de fens après extraction. La gestion des niveaux d’eau s’avère primordiale pour favoriser une structure de végétation semblable à celle retrouvée dans les fens naturels. De trop hauts niveaux d’eau sont à éviter pour empêcher de générer de très hautes émissions de CH₄ et maximiser la fonction de séquestration du carbone. Ce mémoire se divise en trois chapitres : une introduction générale au sujet, suivie d'un corps de mémoire sous forme d'article scientifique puis d’une courte conclusion
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Ndiaye, Oumoule. "Impacts of Water, Extraction Procedure and Origin on Anthocyanins and Volatile Compositions of Hibiscus Extracts and Freeze-Dried Hibiscus." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/88756.
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There has been a lot of interest in Roselle (Hibiscus sabdariffa L.), called Bissap in Senegal, hibiscus recently because of consumer interest in nutraceutical products. However, beverages made from hibiscus have a short self-life due to anthocyanin and flavor degradation. The purpose of our study was first to assess the impacts of water, extraction procedure and origin on the anthocyanins of hibiscus extracts and secondly, to examine the impacts of freeze-drying on the anthocyanins and the volatiles compositions of hibiscus extracts. For the first experiment, a 2x3 factorial design was used with hibiscus calyces from Senegal and Egypt for the factor origin, distilled water and reformulated Dakar (Senegal) water for the second factor water, and then cold and hot extraction procedures were applied. For the second experiment, Senegalese hibiscus was extracted with hot and cold water and one part of each extract was freeze-dried. For both objectives, a ratio of 1:15 w/v (1 kilogram of calyces for 15 liters of water) were used. The time-temperature was 98°C / 30 min for hot and 22°C / 4 hours for cold extractions. The anthocyanins were determined using high performance liquid chromatography (HPLC). And the volatiles were measured using headspace-solid phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GCMS). Origin and temperature as well as their interaction had significant effects on the anthocyanin contents, with respective p-values of 0.0036 and 0.0025 and 0.0002. Freeze-drying showed no effect on the anthocyanins in cold extracts. In contrast, a significant difference between the hot extract and its freeze-dried product was observed with a p-value of 0.0013. For the flavor compounds, the aroma profiles were different between cold and hot extracts and their instant powders. Globally the results of this study can help in the optimization when processing hibiscus derivatives.MSLFS
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Ivkovic, Karen Marie-Jeanne, and kardami@optusnet com au. "Modelling Groundwater-River Interactions for Assessing Water Allocation Options." The Australian National University. Centre for Resources, Environment and Society, 2007. http://thesis.anu.edu.au./public/adt-ANU20080901.134545.
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The interconnections between groundwater and river systems remain poorly understood in many catchments throughout the world, and yet they are fundamental to effectively
managing water resources. Groundwater extraction from aquifers that are connected to river systems will reduce river flows, and this has implications for riverine ecosystem
health, water security, aesthetic and cultural values, as well as water allocation and water management policies more generally. The decline in river flows as a consequence
of groundwater extractions has the potential to threaten river basin industries and communities reliant on water resources.
¶
In this thesis the connectivity between groundwater and river systems and the impact that groundwater extractions have on river flows were studied in one of Australias most developed irrigation areas, the Namoi River catchment in New South Wales.
¶
Gauged river reaches in the Namoi River catchment were characterised according to three levels of information: 1) presence of hydraulic connection between aquifer-river
systems; 2) dominant direction of aquifer-river flux; and 3) the potential for groundwater extraction to impact on river flows. The methods used to characterise the river reaches included the following analyses: 1) a comparison of groundwater and river
channel base elevations using a GIS/Database; 2) stream hydrographs and the application of a baseflow separation filter; 3) flow duration curves and the percentage of
time a river flows; 4) vertical aquifer connectivity from nested piezometer sites; and 5) paired stream and groundwater hydrographs.
¶
The theoretical responses for gaining, losing and variably gaining-losing river reaches were conceptualised along with the processes that operate in these systems. Subsequently, a map was prepared for the Namoi River catchment river reaches
indicating aquifer-river connectivity and dominant direction of flux. Large areas of the Upper Namoi River catchment were found to have connected aquifer-river systems,
with groundwater extraction bores located in close proximity to the rivers. Accordingly, the potential for groundwater extraction to impact on river flows in these areas was
considered significant. The Lower Namoi was assessed as having mostly disconnected aquifer-river systems.
¶
In order to investigate the impacts of groundwater extraction on river flows in
connected aquifer-river systems, a simple integrated aquifer-river model entitled IHACRES_GW was developed for use at the catchment scale. The IHACRES_GW model includes a dynamic, spatially-lumped rainfall-runoff model, IHACRES, combined with a simple groundwater bucket model that maintains a continuous water
balance account of groundwater storage volumes for the upstream catchment area relative to the base of the stream, assumed to be the stream gauging station. The IHACRES_GW model was developed primarily: 1) to improve upon existing water
allocation models by incorporating aquifer-river interactions; 2) to quantify the impacts of groundwater extraction on river flows within unregulated, connected aquifer-river
systems; 3) to inform water policy on groundwater extraction; and 4) to be able to utilise the model in future integrated assessment of water allocations options at the catchment scale.
¶
The IHACRES_GW model was applied within the Coxs Creek subcatchment in order to test its validity. The model was used to simulate a range of extraction scenarios which enabled the impacts of groundwater extractions on river flows to be assessed. In
particular, the historical impacts of groundwater extraction on the timing, magnitude and frequency of baseflow events were quantified over a 15-year (1988-2003) simulation period. The IHACRES_GW model was also used to evaluate the implications of water sharing plans for the Coxs Creek subcatchment.
¶
A spatially-lumped modelling approach in the management of water resources has a number of limitations, including those arising from the lack of spatial considerations. However, it offers a number of advantages including facilitating a better understanding
of large-scale water management issues, assessing the impacts of water allocation and groundwater extraction on river flows at the catchment scale, and informing water sharing plans. In particular, this type of modelling approach lends itself to integrated
assessments of water allocation options in which hydrological, ecological and socioeconomic
data sets are combined, and where data is commonly aggregated to a larger scale of interest in response to the requirements of policy makers. The research findings from this thesis provide some insights into how to better manage the impacts of
groundwater extraction in connected aquifer-river systems.
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Yoboue, Koffi Kouadio Michel. "La question de la remédiation environnementale résultant de l'exploitation artisanale, à petite échelle du diamant : cas de l'Union du fleuve Mano." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30013/document.
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L'exploitation artisanale, à petite échelle du diamant se pratique dans tous les pays de l'Union du Fleuve Mano (Côte d'Ivoire, Guinée, Libéria et Sierra Leone) de façon rudimentaire et parfois de façon informelle. L'exploitation minière artisanale du diamant offre cependant une importante stratégie de subsistance aux communautés locales car elle constitue l'activité principale de la plupart des travailleurs mineurs dans l'Union du Fleuve Mano (UFM). Il ressort de nos études de terrain et des enquêtes auprès des artisans mineurs que ce type d'exploitation minière a des impacts directs sur les galeries forestières, le sol et les cours d'eau. De plus, nous montrons que la réduction des impacts environnementaux engendrés par l'exploitation artisanale, à petite échelle de diamants n'est pas ressentie comme une nécessité ni comme une préoccupation majeure au sein de la communauté des artisans mineurs. Il y a souvent de la part des artisans mineurs un manque de compréhension des problèmes environnementaux et une insuffisante capacité à y faire face, comme le révèle notre étude menée sur trois sites Bobi, Toubabouko et Tortiya en Côte d'Ivoire. Les aires protégées au titre de leurs biodiversités, qui revêtent une importance écologique et socioéconomique majeure pour les populations des pays de la région de l'UFM, subissent malheureusement des pressions importantes du fait de cette exploitation minière artisanale du diamant. D'autant que bien souvent la population des artisans mineurs des sites enquêtés se révèle être en situation socio-économique très précaire et être souvent préoccupée par sa survie dans des conditions très difficiles. Ces dernières années, le Processus de Kimberley a pris l'initiative de concentrer sa réflexion et son action sur les questions environnementales. En 2012, la Déclaration de Washington, relative à l'intégration du développement de l'extraction artisanale et à petite échelle de diamants dans la mise en application du Processus de Kimberley, a souligné l'importance de prendre en considération les ramifications et conséquences environnementales de l'extraction minière artisanale. Dans cette optique, une enquête auprès des artisans mineurs en Côte d'Ivoire et une auto-évaluation de cette déclaration effectuée en 2014 en Côte d'Ivoire ont permis de comprendre que le cadre juridique, social, institutionnel et politique, constaté dans l'État Ivoirien, n'était pas toujours adapté au règlement des problèmes sociaux des artisans mineurs ni au règlement des questions environnementales soulevées par leurs activités minières. Ce travail de diagnostic de la déclaration devrait servir de modèle aux autres États de l'UFM. Les impacts des activités minières artisanales sur l'environnement existent donc mais il semble aussi que la remédiation des sites miniers artisanaux soit possible. En effet, le secteur de l'exploitation artisanale, à petite échelle de diamants a besoin de procédures de remédiation environnementale simples et de protocoles adaptés au niveau d'éducation des artisans mineurs et de leurs réalités financières. A ce sujet, la Sierra Leone a été un terrain privilégié d'expérimentation de la remédiation des sites miniers abandonnés à travers des projets gouvernementaux et des projets pilotes comme "Life after diamonds: Land Reclamation for Agriculture and Advocacy Pilot Initiative ". Ces projets ont contribué à protéger l'environnement et à améliorer les conditions socio-économiques des exploitants miniers. Cependant ces projets de remédiation quoique salutaires, ont eu aussi des limites qui méritent d'être prises en compte dans les futures initiatives des autres pays de l'UFMArtisanal and small-scale diamond mining is practiced in all countries of the Mano River Union (Côte d'Ivoire, Guinea, Liberia and Sierra Leone) in a rudimentary and informal manner. However artisanal diamond mining is an important means of livelihood for most local communities in the Mano River Union. Based on our field research and surveys of miners, this type of mining has direct impacts on the forest ecosystem, soil and watercourses. In addition, the research shows that reducing the environmental impacts of artisanal and small scale diamond mining is not seen as a necessity or a major concern in the mining communities. There is often a lack of understanding and insufficient capacity to deal with environmental problems among artisanal miners, as revealed in our study of three mining sites in Côte d'Ivoire; Bobi, Toubabouko and Tortiya. Protected areas, which are of major ecological and socioeconomic importance for the populations of the Mano River Union countries, are unfortunately under pressure because of artisanal diamond mining. Especially since artisanal miners at the surveyed sites are often in precarious socio-economic situations more preoccupied by means of survival under very difficult working conditions. In recent years, the Kimberley Process has been focusing on environmental issues. In 2012, the Washington Declaration on Integrating Development of Artisanal and Small-Scale Diamond Mining in the implementation of the Kimberley Process highlighted the importance of considering the ramifications and environmental consequences of artisanal mining. To this end, a survey of artisanal miners in Côte d'Ivoire in 2014 made it clear that the legal, social, institutional and political framework of the Ivorian government, was neither adapted to the solution of the social problems of miners nor to the settlement of environmental problems caused by mining activities. This diagnosis should serve as a model for the other countries of the Mano River Union. The reclamation of artisanal mining sites is therefore possible in spite of the environmental impacts of artisanal mining. In fact there is a need for reclamation procedures and protocols adapted to the educational and financial realities of artisanal miners. In this regard, Sierra Leone has been a model in reclamation of abandoned mining sites through pilot projects such as "Land after Diamonds: Land Reclamation for Agriculture and Advocacy Pilot Initiative". These projects have helped to protect the environment and improve the socio-economic conditions of artisanal miners. However, these reclamation projects, although salutary, also have limitations which deserve to be taken into account in future initiatives of the other countries of the Mano River Union
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Bouchez, Alice. "Optimisation multicritère de procédés incluant les impacts environnementaux : cas de l'éco-extraction de biomolécules antioxydantes à partir de coproduits agroalimentaires." Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1R023.
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Pour répondre à l’enjeu actuel majeur d’amélioration de la performance environnementale des procédés, une méthodologie pour l’optimisation multicritère d’éco-procédés incluant les aspects de productivité, énergétiques et environnementaux a été proposée. Dans cette étude, elle a été appliquée au cas de la récupération de polyphénols antioxydants à partir d’un coproduit agroalimentaire. L’optimisation prend en compte les rendements en polyphénols totaux et l’activité antioxydante des extraits obtenus à partir de graines de betterave déclassées ainsi que la consommation d’énergie des équipements impliqués et les impacts environnementaux générés pendant le cycle de vie du procédé. Les procédés d’extraction assistée : par ultrasons (US), par micro-ondes (MO) et par l’association de ces deux technologies ont été étudiés. Pour chaque procédé un modèle global a été développé comme outil pour l’optimisation multicritère intégrant selon l’étude des paramètres opératoires parmi le temps, la composition du solvant, le ratio solvant/coproduit, la puissance des US, la puissance des MO et le volume du solvant. Le modèle a été obtenu en combinant des équations cinétiques avec les méthodes de plan d’expérience et d’analyse de cycle de vie. Cet outil permet de prédire les conditions optimales de fonctionnement de chaque procédé en respectant diverses contraintes spécifiques telles que la maximisation du rendement d’extraction et/ou la minimisation du temps d’extraction, de la consommation d’énergie et/ou des impacts environnementaux. Cette méthodologie pourrait facilement être adaptée pour l’optimisation multicritère d’autres procédésTo meet the current major challenge of improving the environmental performance of processes, a methodology for the multi-criteria optimisation of green processes including productivity, energy and environmental aspects has been proposed. In this study, it was applied to the case of antioxidant polyphenols recovery from an agri-food by-product. The optimisation takes into account the total polyphenol yield and the antioxidant activity of extracts obtained from declassified beet seeds, as well as the energy consumption of the equipment involved and the environmental impacts generated during the process life cycle. Extraction processes assisted by ultrasound (US), microwave (MO) and a combination of these two technologies were studied. For each process, a global model was developed as a tool for multi-criteria optimisation, integrating parameters such as time, solvent composition, solvent/by-product ratio, US power, MO power and solvent volume, depending on the study. The model was obtained by combining kinetic equations to the methods of experimental design and life cycle assessment. This tool allows to predict the optimal operating conditions for each process while respecting specific constraints such as maximising extraction yield and/or minimising extraction time, energy consumption and/or environmental impacts. This methodology could easily be adapted for multicriteria optimisation of other processes
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Mendes, João Carlos Teixeira. "Alternativas de colheita de Eucalyptus e seus impactos no solo e na vegetação nativa em processo de regeneração num plantio abandonado." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-04012013-104545/.
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Essa pesquisa avaliou os efeitos de três sistemas de colheita de madeira sobre os atributos físicos do solo e estruturais da vegetação nativa do sub-bosque, num talhão de Eucalyptus saligna Smith. abandonado há 40 anos. A área experimental se encontra na Estação Experimental de Ciências Florestais da ESALQ-USP, no município de Itatinga/SP. O delineamento experimental aplicado foi de blocos ao acaso, com nove parcelas e três repetições, devido à constatação no sítio de heterogeneidade espacial da densidade de eucalipto e da vegetação nativa. Foram testados três tratamentos: CCV - colheita convencional com extração mecanizada; CIR1 - colheita de impacto reduzido com extração mecanizada; e CIR2 - colheita de impacto reduzido com associação de extração animal para lenha (DAP 30 cm) e com extração mecanizada para tora (DAP > 30 cm). As medições de densidade, resistência à penetração e distúrbios na superfície do solo, e danos na vegetação do sub-bosque, foram realizadas em duas etapas, após a extração de lenha e após a extração de tora. As variáveis para o estudo dos efeitos no solo foram: quatro classes de distúrbios superficiais (m2.ha-1): sem dano, leve, moderado e severo; resistência à penetração (MPa); e densidade aparente (g.cm-3). Os resultados evidenciaram a ocorrência de valores acima do nível crítico teórico para resistência à penetração e densidade, 2,5 MPa e aumento relativo de 15%, respectivamente, nas classes de distúrbios moderado e severo e com o uso de extração mecanizada. No final da colheita, os tratamentos CIR1 e CIR2 apresentaram menor área com essas classes de distúrbios, com 1.151 m2.ha-1 e 1.094 m2.ha-1, respectivamente, diferenciando-os estatisticamente em relação ao CCV com 2.620 m2.ha-1. As variáveis para o estudo dos efeitos na estrutura da vegetação foram: três classes de danos em árvores: intactas, danificadas e mortas; e área basal remanescente (m2.ha-1). No final da colheita, os tratamentos CIR1 e CIR2 apresentaram valores relativos menores de árvores mortas, 33% e 38%, respectivamente, diferenciando-os estatisticamente em relação ao CCV que apresentou uma taxa de 49%. Os tratamentos CIR1 e CIR2 apresentaram maiores valores de área basal remanescente, 5,50 m2.ha-1 e 5,40 m2.ha-1, respectivamente, diferenciando-os estatisticamente do CCV que apresentou área basal de 4,32 m2.ha-1. No geral, concluiu-se que a ocorrência de efeitos significativos nos atributos físicos do solo e na estrutura da vegetação é um fato inevitável na extração de madeira. Entretanto, comprovou-se, com os tratamentos CIR1 e CIR2, que é possível minimizar os distúrbios moderado e severo no solo, reduzir a morte de árvores e promover maior área basal remanescente de espécies nativas. Assim, os sistemas de colheita de impacto reduzido se mostraram como melhores alternativas para a extração de madeira em talhões abandonados de eucalipto, como parte do manejo florestal para revertê-los em reserva legal.This study assessed the effects of three Eucalyptus harvesting systems on physical attributes of the soil and structure of the native vegetation of understory, in a stand of Eucalyptus saligna Smith. abandoned for 40 years. The study area is situated in the Experimental Station of Forest Resources Science of ESALQ-USP (University of São Paulo - Brazil) in the municipality of Itatinga - São Paulo state - Brazil. The experiment was a randomized block design, with nine parcels and three repetitions, due to the spatial heterogeneity of eucalypt density and native vegetation. Three treatments were analyzed: CCV - conventional harvesting with mechanized extraction; CIR1 - reduced impact with mechanized harvesting; and CIR2 - reduced impact harvesting for firewood associated with animal extraction (DBH 30 cm) and with mechanized extraction for logs (DBH > 30 cm). The analyses bulk density, penetration resistance, soil disturbance and vegetation damages were performed in two phases: after extraction for firewood and for logs. The variables for the study on soil effects were: four classes of surface disturbances (m2.ha-1): \"no-disturbances\", \"light\", \"moderate\" and \"severe disturbances\"; penetration resistance (MPa) and bulk density (g.cm-3). The results showed the occurrence of critical theoretical values for penetration resistance (2.5 MPa) and relative increase over 15% for bulk density, on the classes of moderate and severe disturbances with the use of mechanized extraction. At the end of the harvesting, the treatments CIR1 and CIR2 showed smaller area of these classes of disturbances, with 1,151 m2.ha-1 and 1,094 m2.ha-1, respectively, statistically different in relation to CCV, with 2,620 m2.ha-1. The variables for studies on effects of vegetation structure were: three classes of tree damages: intact, damaged and dead; and remaining basal area (m2.ha-1). At the end of the harvesting, the treatments CIR1 and CIR2 showed relatively lower rates of dead trees, 33% and 38%, respectively, statistically differing in relation to CCV, which showed a rate of 49%. The treatments CIR1 and CIR2 showed higher values for basal area, 5.50 m2.ha-1 and 5.40 m2.ha-1, respectively, statistically differing from CCV that showed basal area of 4.32 m2.ha-1. Final conclusions were, that the occurrence of significant effects of physical attributes of soil and vegetation structure is an inevitable fact in wood extraction. However, treatments CIR1 and CIR2 allowed to conclude that it is possible to minimize moderate and severe disturbances in the soil, reduce tree deaths and promote larger remaining basal area of native species. Therefore, the harvesting systems of reduced impact are the best alternatives for wood extraction in abandoned eucalypt stands, as a managing process of forests to turn them into areas of legal reserve.
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CASTRO, FLAVIA J. de. "Avaliação ecotoxicológica dos percolados das colunas de cinza de carvão e de solos com cinza de carvão utilizando Lactuca sativa e Daphnia similis como organismos teste." reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10517.
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Made available in DSpace on 2014-10-09T12:41:24Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:03:39Z (GMT). No. of bitstreams: 0
Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Perreault, Véronique. "Prétraitement d'un isolat de protéines de lin par haute pression hydrostatique : impacts sur la structure protéique, l'hydrolyse enzymatique et les capacités antioxydantes des hydrolysats finaux." Master's thesis, Université Laval, 2016. http://hdl.handle.net/20.500.11794/26804.
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Les graines de lin sont des oléagineux largement cultivés au Canada. Cependant, les résidus générés suite au processus d’extraction de l’huile contiennent une importante quantité de protéines et peuvent être valorisées dans l’alimentation humaine en raison, principalement, de certaines fractions peptidiques possédant des propriétés bioactives. Dans le cadre de ce travail, l’influence des hautes pressions hydrostatiques (HPH) sur un isolat de protéines de lin a été étudiée concernant les modifications de la structure protéique, l’hydrolyse enzymatique ainsi que l’activité antioxydante des hydrolysats. Ainsi, des solutions protéiques de lin (1% m/v) ont été soumises à un traitement de HPH à 600 MPa pendant 5 et 20 minutes, à 20°C et comparés à des échantillons non-pressurisés. Deux traitements subséquents d’hydrolyse ont été effectués suite au traitement ou non de pressurisation : une première hydrolyse trypsique suivie d’une deuxième par la pronase. Dans un premier temps, la caractérisation de l’isolat protéique de lin pressurisé et non pressurisé a été réalisée par spectrofluorimétrie et par une analyse de la taille des particules afin d’étudier l’effet de la pressurisation sur les HPH la matrice protéique végétale. Par la suite, les hydrolysats protéiques ont été caractérisés par HPLC-MS et leur capacité antioxydante a été déterminée par ORAC. Les résultats ont démontré que le niveau de pressurisation et la durée du traitement ont un impact sur la structure protéique en induisant la dissociation des protéines, et la formation d’agrégats. Ceux-ci seraient occasionnés par la décompression ou créés durant l’entreposage des isolats. Suite à l’hydrolyse enzymatique des solutions protéiques pressurisées ou non par la trypsine seule et par la trypsine-pronase, les analyses chromatographiques ont révélé que la concentration de certains peptides a été modifiée lorsque la trypsine seule était utilisée après un traitement à HPH. Enfin, les HPH ont amélioré la capacité antioxydante des hydrolysats obtenus lors de l’hydrolyse trypsine-pronase comparativement au contrôle non-pressurisé.Flaxseed is an oilseed widely cultivated in Canada. However, residues generated after oil extraction contains large amount of proteins and then can be much-valued in human diet due to its bioactive peptide fractions. The influence of high hydrostatic pressure (HHP) on flaxseed protein isolate was studied especially in terms of protein structures, enzymatic hydrolysis and final hydrolysate antioxidant activity. Flaxseed protein solutions (1% w/v) were subjected first to 600 MPa HHP treatments during 5 and 20 minutes at 20°C and were compared to non-pressurized samples. Two subsequent hydrolysis treatments were performed on pressure or non-pressure treated samples: tryptic hydrolysis was carried out and another hydrolysis was performed using pronase on tryptic hydrolysates. Firstly, the characterization of treated and untreated flaxseed protein isolates was done by spectrofluorometric and particle size analyses. Thereafter, flaxseed hydrolysates were analyzed by HPLC-MS and antioxidant capacity by ORAC. These results demonstrated that the pressurizing level and duration had an impact on proteins structure, inducing the dissociation of protein leading subsequently to aggregates. These aggregates were formed by decompression or during further storage. After enzymatic hydrolysis of pressurized or non-pressurized samples by trypsin and trypsin-pronase, chromatographic analyses showed that HHP treatments modified the concentration of certain peptides of the tryptic hydrolysates only. Finally, HHP increases antioxidant capacity (ORAC) of final trysin-pronase hydrolysates when compared to a control.
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Tsiba, Jean-Kevin Aimé. "L'exploitation minière dans la région du Haut-Ogooué (Gabon) : contribution à l'étude des impacts environnementaux." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0361.
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Cette thèse traite des conséquences de l’exploitation du manganèse et de l’uranium sur l’environnement au Gabon, principalement dans la région du Haut-Ogooué. S’agissant du manganèse, exploité à Moanda par la société Comilog, alors filiale du groupe français ERAMET, son extraction entraine d’un côté la métamorphose du paysage et de l’autre côté la pollution physique voire chimique des écosystèmes adjacents. À propos de l’uranium, cette ancienne exploitation de Comuf, filiale du groupe Areva (hérité de COGEMA), est à l’origine d’un passif environnemental qui compose avec la présence anormalement élevée de la radioactivité et la transformation du paysage originel. En fin de compte, ces deux activités révèlent la dualité société/nature au bout de laquelle la nature se transforme désormais rapidement au rythme des activités anthropiques sans cesse croissantes. Elles exposent l’homme aux risques anthropiques dont les conséquences peuvent être fatales. Par conséquent, la crise environnementale née de ces deux minières a suscité les mouvements d’humeurs au sein de la population locale et de la société civile qui accusent l’État Gabonais et les deux protagonistes d’un manque de sérieux de réactivité face au danger qui prévaut dans la région. Au regard de la qualité de vie à Moanda, ville de manganèse et à Mounana, ville d’uranium, il a été question, au bout de ce travail, d’apporter quelques propositions dans l’optique d’un développement durable. On peut citer entre autre la création des structures étatiques telles que la « police des mines » ; des laboratoires d’analyses des données environnementales ; etcThis dissertation is about the consequences of manganese and uranium mining on the environment in Gabon, especially in the Haut-Ogooué province. The extraction of manganese in Moanda, conducted by the Comilog company (a subsidiary of the French ERAMET), has both radically altered the landscape and caused chemical pollution in the local ecosystems. The extraction of uranium, formerly conducted by Comuf (a subsidiary of Areva, then known as COGEMA) has caused severe environmental damage, both in terms of abnormally high radioactivity and landscape alteration. In both cases, the confrontation of nature and society has seen an ever increasingly rapid transformation of nature due to the growth of human activity. Such manmade hazards have potentially fatal consequences. The environmental crisis created by the two mining projects has caused anger in the local population and the civil society at large, with people blaming the government and the companies concerned for not handling the hazards in the area responsibly enough or soon enough. This dissertation suggests several avenues to improve the local quality of life in Moanda (manganese mining) and Mounana (uranium mining) in the perspective of sustainable development. Those suggestions include the creation of public structures such as the “mine police” and of analysis laboratories in charge of environmental data
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Martinez, Noguez Abraham Isaac [Verfasser], Reinhard [Akademischer Betreuer] Hinkelmann, Reinhard [Gutachter] Hinkelmann, Savidis [Gutachter] Stavros, and Rainer [Gutachter] Helmig. "Impacts of fast water infiltration in fault zones and water extraction on land subsidence / Abraham Isaac Martinez Noguez ; Gutachter: Reinhard Hinkelmann, Savidis Stavros, Rainer Helmig ; Betreuer: Reinhard Hinkelmann." Berlin : Technische Universität Berlin, 2017. http://d-nb.info/1156178088/34.
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Velho, Eduarda Leoneth Gaspar Mulende. "O impacto ambiental da extração petrolífera: Estudo sobre a (re) evolução do Direito Ambiental." Master's thesis, Universidade Portucalense, 2015. http://hdl.handle.net/11328/1536.
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Dissertação de Mestrado em DireitoO trabalho em epígrafe cinge-se na Problemática do impacto ambiental da extração petrolífera, ou seja na (re) Evolução do Direito Ambiental. Ao abordarmos sobre esta temática, é importante referirmos que, de um modo geral, são empresas competentes para o efeito que extraem o petróleo. O petróleo é tido como o recurso natural que fornece a principal fonte de energia ao homem. Ao ser extraído causa-se danos irreparáveis pra os seres vivos e com isso há a necessidade de se encontrar mecanismos de responsabilização das pessoas que os provocam.
The work referred to above gird on the Issues of the environmental impact of oil extraction, that is the (re) Evolution of Environmental Law. When discussing about this matter, it is important to refer, in general, companies are responsible for the effect that draws oil. Oil is considered the natural feature that provides the main source of energy to man. When extracted to cause irreparable damage to living beings and therefore there is a need to find mechanisms accountability of persons they cause.
Orientação: Prof. Doutor Carlos Rodrigues
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Mariet, Anne-Lise. "Contamination en éléments traces métalliques et changements de végétation liés aux activités minières dans le massif des Vosges : approche diachronique et synchronique des impacts environnementaux." Thesis, Besançon, 2016. http://www.theses.fr/2016BESA2077.
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Depuis au moins 2000 ans, le massif des Vosges a été le siège d’activités minières qui ont conduit (i) à l’émission de particules contaminées en éléments traces métalliques (ETMs), (ii) aux dépôts de déchets miniers et sidérurgiques et (iii) à des modifications du paysage. Les ressources présentes dans ce système de moyenne montagne, et utilisées par les populations, rendent nécessaire la mesure des impacts des activités anthropiques passées sur l’écosystème forestier.Ce travail de thèse propose une approche multi-proxy couplant géochimie, palynologie et écotoxicologie. Différentes phases de dépôts en ETMs ont été retracées sur les 2000 dernières années et regroupent celles connues à l’échelle de l’hémisphère Nord et des phases plus locales. L’impact paysager des activités minières semble quant à lui réduit par rapport à ce que laissaient penser les archives historiques qui présentaient des déserts forestiers dus aux activités minières. La biodisponibilité et le risque associés au transfert des ETMs ont été évalués dans un ancien district minier de production de plomb (Pb) et d’argent grâce à une campagne de bioindication active avec un indicateur de la qualité des sols, Cantareus aspersus. Sur huit stations, quatre présentent des excès de transfert induisant un risque toxicologique élevé et comprennent deux sites archéologiques miniers et un potager communal. Le fractionnement et la spéciation du Pb permettent de montrer une pratique à risque avec l’utilisation de scories comme amendements sur le potager. La contamination du milieu en ETMs par les activités minières est ici toujours transférable aux organismes du sol et donc potentiellement dans le réseau trophiqueSince at least the last two millennia, mining and smelting activities have occurred in the Vosges Mountains and conducted to (i) the emission of trace metal (TM) contaminated particles in the atmosphere, (ii) the presence of mining and smelting wastes and (iii) landscape changes. Due to the use of resources from this mountainous area by local populations, it is necessary to measure impacts of these past activities on the forested ecosystem.This PhD thesis proposes a multi-proxy approach coupling geochemistry, palynology and ecotoxicology. Several phases of TM deposits have been recorded and correspond to major phases of TM contamination known in the northern hemisphere and also local periods of mining/smelting activities. The impact of mining activities on the landscape appears to be reduced contrary to historical data that described shortage of wood due to mining activities. The bioavailability and the risk associated to TMs from mining activities have been assessed in a former lead (Pb)-silver mining district by an active bioindication campaign using Cantareus aspersus, considered as indicator of soil quality. Among the eight stations, four of them present an excess of TM transfer conducting to a high ecological risk, particularly in two archaeological mining sites but also in a kitchen garden. Lead fractionation and speciation highlight the use of slags as amendments in the kitchen garden. Trace metal contamination of the soil due to mining activities is still bioavailable for soil organisms and so potentially transferred in food chain
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Ahmad, Alexandre. "Animation de structures déformables et modélisation des interactions avec un fluide basées sur des modèles physiques." Limoges, 2007. https://aurore.unilim.fr/theses/nxfile/default/4f73d6f8-b8f0-4794-924b-8f827db44689/blobholder:0/2007LIMO4046.pdf.
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Je présente dans cette thèse des travaux concernant la simulation d'interactions entre un fluide et des membranes déformables. Ce sujet ne manque pas d'applications puisque l'interaction d'un fluide avec des feuilles, des tissus ou même des nageoires de poisson est un scénario courant. Pourtant, peu de travaux en synthèse d'images se sont intéressés à reproduire ce phénomène. Pour ce faire, je propose un algorithme de réaction de contacts entre un fluide Lagrangien et une membrane déformable qui est indépendant du pas d'intégration temporelle. Afin de pallier les artefacts visuels dus à des triangles, issus du processus d'extraction de surface du fluide, qui passent au travers de la membrane lors d'interactions, je présente une technique qui projette la portion de volume erronée le long de la membrane. De plus, une paramétrisation intuitive de coefficients hétérogènes de friction sur une surface est exposée. Je présente également deux modèles d'optimisation. Le premier modèle propose de filtrer les vitesses de particules calculées par une méthode explicite afin de réduire la forte contrainte sur le pas d'intégration temporelle. Des analyses fréquentielles permettent de quantifier cette réduction. Le deuxième modèle est une structure de subdivision spatiale dynamique qui détermine efficacement le voisinage d'un point et d'un triangle. Cette structure a pour but de réduire les temps de calculs des processus de détermination du voisinage pour les fluides Lagrangiens, mais aussi ceux de la détection de collisions et enfin ceux de l'extraction de surfaceThe presented works' main focus is the interaction of liquids and thin shells, such as sheets of paper, fish fins and even clothes. Even though such interactions is an every day scenario, few research work in the computer graphics community have investigated this phenomenon. Thereby, I propose an algorithm which resolves contacts between Lagrangian fluids and deformable thin shells. Visual artefacts may appear during the surface extraction procedure due to the proximity of the fluids and the shells. Thus, to avoid such artefacts, I propose a visibility algorithm which projects the undesired overlapping volume of liquid onto the thin shells' surface. In addition, an intuitive parametrisation model for the definition of heterogeneous friction coefficients on a surface is presented. I also propose two optimisation methods. The first one reduces the well-known dependency of numerical stability and the timestep when using explicit schemes by filtering particles' velocities. This reduction is quantified with the use of frequency analysis. The second optimisation method is a unified dynamic spatial acceleration model, composed of a hierarchical hash table data structure, that speeds up the particle neighbourhood query and the collision broad phase. The proposed unified model is besides used to efficiently prune unnecessary computations during the surface extraction procedure
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Simões, Cláudia Sofia Lola. "Modelação da erosão do solo numa região de forte impacte de actividades mineiras e estudo geoquímico das zonas mais vulneráveis, com vista à sua remediação e reabilitação. Estudo de uma área piloto da Bacia do rio Paraopeba (Bacia do Rio Paraopeba - MG, Brasil)." Doctoral thesis, Universidade de Évora, 2015. http://hdl.handle.net/10174/16404.
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A erosão acelerada resulta em graves consequências para a qualidade do solo e da água, assim
como para a sustentabilidade dos sistemas agrários.
Para caso de estudo seleccionou-se a bacia hidrográfica do Rio Paraopeba, localizada na região
sudoeste do Brasil, na área denominada de Quadrilátero Ferrífero, onde a intensa actividade
mineira, se reflecte, não apenas no agravamento dos processos erosivos, mas também, na
qualidade da água e do solo.
No trabalho desenvolvido, identificaram-se as zonas mais vulneráveis aos processos erosivos,
tendo como base metodologias de modelagem matemática computacional e efectuou-se o
estudo geoquímico dos solos, tendo em vista a definição das tecnologias mais adequadas para a
remediação da bacia.
Os trabalhos desenvolvidos permitiram identificar situações de contaminação de solos e
apresentar soluções para a sua remediação. Desta forma, foi validada a metodologia de estudo
proposta, que se considera viável para ser adaptada ao estudo de outros locais; ABSTRACT:
MODELLING OF SOIL EROSION IN A STRONG IMPACT REGION OF MINING AND
GEOCHEMICAL STUDY OF THE MOST VULNERABLE AREAS, WITH A VIEW TO
REMEDIATION AND REHABILITATION. STUDY OF AN AREA OF THE BASIN OF THE
PARAOPEBA RIVER (MINAS GERAIS, BRAZIL)
The accelerated erosion results in serious consequences for the quality of soil and water, as
well as to the sustainability of agricultural systems.
For case study was selected to Paraopeba River Basin, located in the southwestern region of
Brazil, in the area known as the Iron Quadrangle, where intense mining activity, reflected not
only in the increase of erosion, but also in quality water and soil.
In the work, the most vulnerable areas to erosion were identified, based on methodologies of
computational mathematical modeling and worked up geochemical study of the soil, with a
view to defining the most appropriate technologies for the remediation of the basin.
The developed works have identified soil contamination, and provide solutions to their
remediation. Thus, it was validated the study proposed methodology, it is considered feasible
to be adapted to study other locations.
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Driche, Khaled. "Diamond unipolar devices : towards impact ionization coefficients extraction." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT115/document.
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97% des articles publiés sur les études climatiques racontent que le réchauffement climatique est entièrement causé par les activités humaines. Les gaz émis lors de la production d'énergie électrique ainsi que d'autres gaz rejetés par les voitures ont un réel impact sur l'atmosphère. Une solution consiste à mettre au point des composants présentant des pertes de conduction plus faibles et des caractéristiques de claquage plus élevées qui pourraient être utilisés dans des centrales nucléaires, des cellules de commutation à haute puissance, des voitures hybrides (électriques), etc.De nos jours, les composants à base de silicium contrôlent environ 95% des dispositifs électroniques. Le carbure de silicium SiC et le nitrure de gallium GaN sont actuellement à l’étape de R&D, et commencent à être intégrés dans certains circuits électroniques. D'autres matériaux tels que Ga2O3, AlN ou le diamant sont encore à l’étape de recherche. Les derniers sont connus sous le nom de matériaux à bande ultra large et semblent être la solution requise pour les faibles pertes de puissance. Le diamant est reconnu comme le matériau ultime pour la prochaine génération de composants de puissance en raison de ses propriétés physiques exceptionnelles telles qu'un champ de claquage élevé (>10 MV/cm) permettant d'utiliser le dispositif pour une commande de puissance élevée, une mobilité de porteurs élevée (2 000 cm^2/V.s pour les trous), une vitesse de saturation élevée, une conductivité thermique élevée (22 W/cm.K) pour une parfaite dissipation de chaleur et une faible constante diélectrique. Théoriquement, le diamant est le semi-conducteur offrant le meilleur compromis entre résistance à l'état passant et tension de claquage. En particulier, en raison de l'ionisation incomplète des dopants, il est encore plus efficace à haute température. Diverses diodes Schottky en diamant (SBD) avec de bonnes performances à l’état passant et bloqué (7,7 MV/cm) ont été rapportées. En plus des SBDs, des transistors à effet de champ (FET) ont également été étudiés à travers des oxyde-métal semi-conducteur FETs (MOSFETs) utilisant une surface hydrogénée avec des densités de courant élevées à l'état passant ou des surface oxygéné avec de bonnes caractéristiques de blocage. Pour les composants de haute-tension, il est nécessaire de changer l’architecture de l’électrode afin d’éviter un claquage prématuré due à l’encombrement du champ électrique aux bords. Dans ce but, les techniques de terminaison de bord sont utilisées pour atteindre les caractéristiques idéales. La tâche évidente avant toute fabrication de composant est la partie simulation qui prédit l’optimisation de l’architecture et les caractéristiques attendues. Une bonne prédiction nécessite la connaissance des paramètres du matériau. Les paramètres importants pour le claquage sont les coefficients d'ionisation par impact. Plusieurs coefficients ont été publiés pour le diamant. Toutefois, ils ont été extraits en « fittant » des structures non optimisées, d'où un manque de précision.Dans cette étude, deux structures de terminaisons de bord pour des diodes Schottky, appelées plaque de champ et anneaux à champ flottant, ont été étudiées. Leur efficacité de distribution du champ de surface par analyse de courant induit par faisceau d'électrons (EBIC) a été observée. De plus, des FETs ont été fabriqués et caractérisés, un MESFET et un RB-MESFET. Les FETs présentent un claquage élevé, jusqu’à 3 kV et une faible résistance. Le développement des transistors est indissociable de la diode Schottky, car ils sont tous deux nécessaires à la fabrication de cellules de commutation. Et enfin, les coefficients d'ionisation par impact pour les électrons ont été mesurés à l'aide d’EBIC pour un champ >0,5 MV/cm dans une région sans défaut. Les valeurs mesurées sont (sous l’equation de Chynoweth) an = 971 /cm et bn=2,39x10^6 V/cm. Ces valeurs sont proches des coefficients mesurés expérimentalement et rapportés dans la littérature97% of the published climate studies articles agree with the fact that recent global warming is entirely caused by human activities. The gases emitted to produce electrical energy plus other gases rejected by cars impact considerably on the atmosphere by greenhouse effect (without referring other factors). A solution to this problem is the development of components with lower power conduction losses and higher breakdown characteristics that could be used in nuclear power plants, high power commutation cells, hybrid (electric) cars and so on.The choice of the material to reach low power conduction losses and higher breakdown is of great importance. Nowadays, silicon-based devices control about 95% of all electronic components. Silicon carbide SiC and gallium nitride GaN are at present under research and development and start to be integrated into some electronic circuits. Other materials like Ga2O3, AlN or diamond are under research for power electronic application. The last ones are known as ultra wide bandgap materials and they seem to be the required solution to low power losses. Diamond is recognized as the ultimate material for the next next-generation of power devices owing to its exceptional physical properties such as high breakdown field (>10 MV/cm) to use the device for high power control, high carrier mobility (2000 cm^2/V.s for holes) for fast switching and high frequency devices, high saturation velocity, high thermal conductivity (22 W/cm.K) for a perfect heat dissipation and low dielectric constant. Theoretically, diamond is the best semiconducting material showing the best trade-off between on-resistance and breakdown voltage. Especially, due to the incomplete ionization of the dopant, it is even more efficient at high temperature. Various diamond Schottky barrier diodes (SBDs) with good forward and reverse performances (7.7 MV/cm) were reported. In addition to SBDs, switches diamond field effect transistors (FETs) were also investigated through metal-oxide-semiconductor FETs (MOSFETs) using either an H-terminated diamond surface with high current densities in on-state or an O-terminated one with high blocking characteristics. For the high blocking voltage devices, one needs to properly terminate the edge of the electrode at the surface in order to avoid premature breakdown of the devices due to electric field crowding at the borders. In that aim, edge termination (ET) techniques are used to push the limit of the devices and reach ideal features. The obvious task before any device fabrication if the simulation part that predicts the device optimization and expected characteristics. A good device prediction requires knowledge of the material parameters. Important parameters for device breakdown in the off-state are the impact ionization coefficients. At present, several ionization coefficients were reported for diamond, however, they were extracted by fitting non-optimized structures and hence there is a lack of accuracy.In this study, two edge terminations structures for Schottky barrier diodes called field plate (FP) oxide and floating field rings were investigated. Their effectiveness in surface field distribution via electron beam induced current (EBIC) analysis was observed. In addition, normally-on FETs were fabricated and characterized, a MESFET and a reverse blocking (RB)-MESFET. The FETs exhibited a high BV, up to 3 kV and a low on-resistance. The development of transistors is inseparable from the Schottky diode since both are required to fabricate commutation cells. And finally, impact ionization coefficients for electrons were measured using EBIC for a field >0.5 MV/cm in a defect-free region. The measured values are (in a Chynoweth form) an = 971 /cm and bn = 2.39x10^6 V/cm. These values are close to the experimentally measured coefficients reported in the literature
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Yao, Kouadio Assemien François. "Développement d'une méthodologie pour une meilleure évaluation des impacts environnementaux de l'industrie extractive." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTG001/document.
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L’industrie minière joue un rôle important dans le développement économique de nos pays. Cependant, les projets miniers font de nos jours face à de sérieuses oppositions tant des communautés locales que des organismes de protection de l'environnement, en raison des impacts potentiels associés à l'extraction minière. Pour concilier les besoins de production de matières premières (assurer le développement économique) et la prise en compte de la préservation de la qualité de l'environnement, il est nécessaire d'évaluer les impacts environnementaux potentiels, conséquences des activités minières avant leur début et choisir les meilleures options d’un point de vue environnemental. L’Étude d’Impact Environnemental (EIE) est une procédure qui permet d’identifier et d’évaluer les impacts d’un projet. Les projets miniers sont assujettis à une telle étude. Or bien que la procédure d’EIE soit obligatoire, la réglementation ne prescrit aucune méthode d’évaluation des impacts ; qui est laissée au choix du praticien. L’objectif général de cette thèse est de proposer une méthode permettant d’évaluer plus efficacement les impacts environnementaux de l’industrie minière. Pour y parvenir deux approches ont été explorées : la méthodologie d’Analyse et d’Évaluation des Impacts environnementaux Miniers (MAEIMIN) développée dans cette thèse et la méthodologie d’Analyse de Cycle Vie (ACV) qui est une technique standardisée ISO. MAEIMIN est une technique basée sur la démarche d’analyse de risque et permet d’évaluer les impacts en prenant en comptes les conditions climatiques, géologiques et de l’état initial de la zone. L’ACV est quant à elle une technique standardisée qui permet d’évaluer les impacts produits sur le site et ceux générés hors du site mais dont les activités génératrices sont liées au système étudié. Ces méthodes ont été mises en œuvre sur une mine d’or en Côte d’Ivoire. MAEIMIN, en prenant en compte les caractéristiques particulières de la zone d’étude, a montré des résultats d’impacts élevés aussi bien pour la pollution des eaux de surface que pour les eaux souterraines, principalement aux étapes d’exploitation et d’après-mine. Cette étude a également montré que les sources de pollution entraînant des impacts de niveau élevé comprennent les dépôts de résidus (terrils et effluents), les sols préalablement contaminées par des retombées de poussière et les travaux miniers. S’agissant de l’ACV, qui est par essence une méthode généraliste, elle a permis plus particulièrement de mettre en évidence des impacts off-site assez significatifs. Pour les effets on-site, l’étude a montré que les impacts sur la santé humaine sont essentiellement dus aux émissions de métaux par les activités d’exploitation (traitement du minerai et gestion des résidus miniers ainsi que les émissions de l’abattage). Enfin, notre travail a permis de montrer une meilleure prise en compte de l’ensemble des impacts par une combinaison de MAEIMIN et de l’ACV dans les procédures d’EIEAn increasing demand of mineral resources is associated with modern society development. In parallel, mining projects face strong oppositions both from public and from environment protection agencies, due to the potential impacts associated with ore extraction. In order to conciliate the needs of producing raw materials and of taking into account the preservation of the quality of the environment, it is necessary to assess the environmental impact previous to the start of the mining activities. The Environmental Impact Assessment procedure helps to identify and evaluate the environmental impacts of a project. Although Environmental Impact Assessment (EIA) procedure is mandatory, the regulations do not impose any impact assessment method. Thus, EIA practitioners are free to use the method that suits them and their own expertise to estimate the environmental impacts of a project. The main purpose of this work is to propose a method to more effectively evaluate the environmental impacts of the mining industry. To achieve this, two approaches have been explored: the Mining Environmental Impact Assessment Methodology (MEIAM) developed in this thesis and the Life Cycle Assessment (LCA), which is a standardized methodology. MEIAM is based on the risk analysis approach and makes it possible to evaluate the impacts taking into account the climatic and geological conditions and the initial state of the zone. LCA is a standardized technique that assesses the impacts produced on the site and those generated off-site but whose generating activities are related to the system studied. These methods were implemented on a gold mine in Côte d’Ivoire.MEIAM, taking into account the particular characteristics of the study area, showed high impact results for both surface water and groundwater pollution, mainly at the operation and post-closure stages. This study has also shown that pollution sources with high level impacts include tailings, soils previously contaminated by dust fallout and mining works. Regarding the LCA, which is in essence an overall method, it has made it possible to highlight quite significant off-site impacts. For on-site effects, the study showed that the impacts on human health are mainly due to metal emissions from operation activities (ore processing and tailings management as well as blasting). Finally, our work showed that all the impacts were better taken into account by a combination of MEIAM and LCA in the EIA procedures
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Goulas, Anaïs. "Devenir et biodisponibilité des antibiotiques entrant dans les sols agricoles lors du recyclage des matières fertilisantes d'origine résiduaire." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLA034/document.
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Des antibiotiques sont introduits de façon chronique dans les sols lors de l’épandage des matières fertilisantes d’origine résiduaire (MAFOR), telles que le fumier ou les boues de station d’épuration. La dissémination de ces polluants dans l’environnement présente un risque à long terme pour la santé en raison notamment de l’apparition de résistances aux antibiotiques. L’origine et les propriétés des MAFOR peuvent influencer le devenir ultérieur des antibiotiques dans les sols. Ce devenir et les effets des antibiotiques sur les organismes vivants dépendent de leur (bio)disponibilité. Peu de données existent sur la (bio)disponibilité des antibiotiques dans les sols car elles sont conditionnées par le développement de méthodes d’extraction et d’analyse des molécules à de faibles teneurs, dans des matrices organo-minérales complexes. Ce travail de recherche se focalise sur les liens entre nature des MAFOR, devenir et biodisponibilité des antibiotiques dans les sols, et impacts sur les micro-organismes du sol. Des méthodes chimiques ont été développées pour estimer la (bio)disponibilité et le devenir de deux antibiotiques (ciprofloxacine et sulfaméthoxazole) et de certains produits de transformation dans les sols amendés par des MAFOR et incubés au laboratoire. Un modèle a été utilisé pour décrire le devenir du sulfaméthoxazole et de son métabolite principal dans les sols en fonction de l’évolution de la matière organique de la MAFOR ; ceci a permis de montrer que le co-métabolisme pouvait être à l’origine de la biodégradation des molécules et de la formation de résidus non-extractibles. Enfin, ces données chimiques ont été confrontées à des mesures biologiques : la (bio)disponibilité des antibiotiques mesurée à l’aide de différentes extractions aqueuses a été reliée à leur biodégradation par des micro-organismes adaptés dans les sols ou à leur toxicité sur les activités nitrifiantes microbiennes des sols. Ce travail a permis d’obtenir des résultats originaux qui pourront être utiles pour une évaluation des risques liés à la dispersion des antibiotiques dans l’environnementAntibiotics are chronically introduced in soils through the application of exogenous organic matter (EOM) such as manure or sewage sludge. The environmental dissemination of these pollutants presents a long-term risk for health particularly due to the acquisition of antibiotic resistances. The origin and the properties of EOM can influence the antibiotic behavior in soils. This behavior and the potential impact on living-organisms depends on the antibiotic (bio)availability. Few data about the antibiotic bioavailability in soils exist and increasing knowledge is conditioned by the development of extraction and analytical methods for molecules at low concentrations in complex organomineral matrices. This research work focuses on the link between the MAFOR type, the behavior and the bioavailability of antibiotics in soils, and their impacts on soil microorganisms. Chemical methods were developed to assess the(bio)availability and the behavior of two antibiotics (sulfamethoxazole and ciprofloxacin) and some transformation products in EOM-amended soils incubated in controlled conditions. A modelling approach was used to describe the behavior of sulfamethoxazole and its main metabolite in soils as a function of the organic matter evolution; the modelling results suggest that co-metabolism was responsible for the molecule mineralization and the formation of biogenic non-extractable residues. Finally chemical data were confronted to biological measures: the (bio)availability of antibiotics estimated through different aqueous extractions was related to their biodegradation by adapted soil microorganisms or to their toxicity on soil microbial activities. Original results were obtained in this work and will be useful to assess the risk related to the antibiotic dispersion in the environment
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Gharaibeh, Ahmed. "Environmental impact assessment on oil shale extraction in Central Jordan." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2017. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-226424.
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This study focuses on the environmental impact assessment of trace elements concentrations in spent shale, which is the main residual besides gas and steam from the utilization of oil shale.
The study area El-Lajjun covers 28 km2, located in the centre of Jordan approximately 110 km south of Amman. It belongs mainly to the Wadi Mujib catchment and is considered to be one of the most important catchments in Jordan.
The Wadi El-Lajjun catchment area (370 km2) consists of two main aquifer systems: The intermediate aquifer (Amman Wadi As Sir Aquifer or B2/A7) and the deep sandstone aquifer (Kurnub/Ram Group Aquifer). The B2/A7 aquifer (Upper Cretaceous) is considered as the main source of fresh water in Jordan.
El-Lajjun oil shale was deposited in a sedimentary basin and comprises massive beds of brown-black, kerogen-rich, bituminous chalky marl. The oil shale was deposited in shallow marine environment. It is by definition a sedimentary rock containing organic material in the rock matrix. The shale oil extraction is an industrial process to decompose oil shale and to convert the kerogen into shale oil by hydrogenation, pyrolysis or by a thermal dissolution.
Several classifications of extraction technologies are known; the classification with respect to the location where the extraction takes place distinguishes between off-site, on-site, and in situ. The oil shale utilization may have serious repercussions on the surrounding environment if these issues are not investigated and evaluated carefully.
Ten representative oil shale rock samples with a total weight about 20 kg were collected from different localities of oil shale exposures in the study area. A standardized laboratory Fischer Assay test was performed with the samples to determine oil shale characteristics and to obtain spent shale, which was used in this study for further investigations. Sequential extraction was used to evaluate the changes in the mobility and distribution of the trace elements: Ti, V Cr, Co, Zn, As Zr, Cd, Pb and U. Column leaching experiments were performed to simulate the leaching behavior of the above elements from oil shale and spent shale to evaluate the possible influence on the groundwater in the study area. The concentrations in the leachate were below the maximum contaminant levels of the Environmental Protection Agency (EPA) for drinking water and the Jordanian standards for drinking water.
An immobilization method by using Kaolin was applied to reduce the mobilization and bioavailability of the trace elements fraction that are contained in the spent shale. Immobilization was evaluated as a function of liquid-solid ratio (solid-liquid partitioning) and as a function of pH. A comparison between the results obtained from column leaching experiments and the results that were obtained from immobilization for the oil shale and spent shale samples indicated that the immobilization reduced the mobility of the trace element except for Ti, V, and Cr. However, even the concentrations of these elements were lower than the maximum acceptable limits of the Jordanian Standard Specifications for waste water.
The catchment of the study area (Wadi El-Lajjun catchment) is ungauged. Therefore, the soil conservation service (SCS) runoff curve number method was used for predicting direct runoff from rainfall. The results obtained showed that the infiltration of water is very small (approximately 0.6 cm/year) and rarely can´t reach the groundwater through the oil shale beds. Thus, a contamination of groundwater is unlikely under normal conditions.
DRASTIC was used to assess groundwater vulnerability for the B2/A7 aquifer with respect to pollution by oil shale utilization. The aquifer vulnerability map shows that the area is divided into three zones: low (risk index 10-100; intermediate (risk index 101–140) and high groundwater vulnerability (risk index 141-200). The high risk areas are small and mainly located in the northeastern corner of the El-Lajjun graben, where the hydraulic conductivity is relatively high and rocks are highly fractured and faulted.
The water table of the deep sandstone aquifer (Kurnub/Ram group) in the El-Lajjun area is relatively deep. At least two geological formations above the Kurnub aquifer are aquitards and protect the deep aquifer. However, the area is highly fractured and thus there is a certain possibility for contact with surface pollutants.
Finally, further research with respect to trace elements including REE elements and isotopes in the intermediate and deep sandstone aquifers are highly recommended. Isotopic signatures will be very helpful to investigate to which extend hydraulic connections between the aquifers exist.
Further and in particular mineralogical studies on the spent shale and the possibilities for industrial utilization are recommended because huge quantities of spent shale are expected. Because most oil shale extraction technologies especially the power generation require considerable amounts of water detailed studies on water supply for the oil shale treatment have to be performed.
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Qirreish, Emad Eddin Yacob Juma. "Radiographic profile of symptomatic impacted mandibular third molars in the Western Cape, South Africa." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
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It is common practice to remove impacted mandibular third molars due to pathology associated with these impactions. Alternatively, impactions can be treated conservatively through a closely guarded follow-up regiment. However, many symptoms associated with impacted third molars may be prevented by elective removal of potentially problematic teeth. To determine the risk of developing pathology associated with impacted mandibular third molars, a ransom sample of 200 pantomographs were analyzed displaying 324 impactions from patients who presented for treatment at the Maxillo-Facial and Oral Surgery Department, Faculty of Dentistry, University of the Western Cape.
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Bekiroglu, Yasemi. "Nonstationary feature extraction techniques for automatic classification of impact acoustic signals." Thesis, Högskolan Dalarna, Datateknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:du-3592.
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Condition monitoring of wooden railway sleepers applications are generallycarried out by visual inspection and if necessary some impact acoustic examination iscarried out intuitively by skilled personnel. In this work, a pattern recognition solutionhas been proposed to automate the process for the achievement of robust results. Thestudy presents a comparison of several pattern recognition techniques together withvarious nonstationary feature extraction techniques for classification of impactacoustic emissions. Pattern classifiers such as multilayer perceptron, learning cectorquantization and gaussian mixture models, are combined with nonstationary featureextraction techniques such as Short Time Fourier Transform, Continuous WaveletTransform, Discrete Wavelet Transform and Wigner-Ville Distribution. Due to thepresence of several different feature extraction and classification technqies, datafusion has been investigated. Data fusion in the current case has mainly beeninvestigated on two levels, feature level and classifier level respectively. Fusion at thefeature level demonstrated best results with an overall accuracy of 82% whencompared to the human operator.
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Li, Xiaorong. "Three-dimensional modelling of tidal stream energy extraction for impact assessment." Thesis, University of Liverpool, 2016. http://livrepository.liverpool.ac.uk/3006766/.
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This research is themed around development of a tidal turbine simulation platform based on a three-dimensional oceanographic numerical modellling environment; more specifically, parameterization of effects of tidal turbine on flow current, turbulence, waves and sediment transport. In this context, the author adopts concepts in the current module, the turbulent module, the wave module and the sediment transport module of Finite-Volume, primitive equation Commmunity Ocean Model (FVCOM) to simulate the effects of tidal turbines. The retarding force concept is employed in the current module, working as an additional body force exerted on the water to simulate the turbine induced water deceleration. Three terms are added into the MY-2.5 turbulence closure to model turbine related turbulence generation, dissipation and turbulence length-scale interference. The built-in feature 'OBSTACLE' of the wave module is used to simulate the reduction of wave height caused by the turbine. The enhanced sediment suspension due to the turbine in motion is represented by an additional bottom shear stress term, entraining an extra portion of sediment particles from the bed into the water. Due to the fact that the bedload sediment transport module of FVCOM is not fully developed, it is not considered in this research; development of such a module is beyond the scope of this project. Coefficients of the turbine simulation terms are calibrated based on experimental data collected in the 'Total Environment Simulator laboratory flume' at the University of Hull, in which a prototype experiment was conducted. Small scale simulations carried out using ANSYS FLUENT also provided complementary calibration data. An idealized water channel model with mesh resolution fined down to the size of the simulated turbine is built to carry out the coefficient calibration. In general, the developed turbine simulation platform is capable of predicting reliable flow velocity, turbulent level, wave height and suspended sediment transport in the far wake region of the turbine, given proper values assigned to the relating coefficients. In addition, preliminary sensitivity tests are carried out to investigate the impact of these coefficients to the model's overall prediction to reveal the model's application range. Upon the satisfactory choices of the coefficients, the platform is applied to a 15m scale idealized single turbine case as well as a regional scale case based on the realistic hydrodynamics off the Anglesey coast, north-west of Wales. A series of single turbine tests are carried out with and without the turbine implementations, i.e. the coefficients represent turbine effects being switched on and off, in order to reveal the differences between the baseline case (no turbine) and case with turbine effects. Under realistic natural tidal and wave conditions, the Anglesey coast case showcases impact from a large scale turbine farm to both local and regional processes.
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Satakopan, Hariram. "Time-Frequency Feature Extraction for Impact Sound Quality Analysis with Emphasis on Automobile Applications." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1299168649.
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Tipsrisukond, Narin. "Impact of lipid degradation processes, and supercritical carbon dioxide extraction on flavor characteristics of lard /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p3091972.
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Sajnani, Anand Kumar. "Impacted canines: characteristics, prevalenceand implications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B44173350.
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Haddad, Mohamed Hatem. "Extraction et impact des connaissances sur les performances des systèmes de recherche d'information." Phd thesis, Université Joseph Fourier (Grenoble), 2002. http://tel.archives-ouvertes.fr/tel-00004459.
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Dans un contexte riche d'information, un système de recherche d'information doit être capable de trouver les meilleurs résultats possibles dans un océan d'information. Notre étude s'intéresse aux connaissances qui peuvent être extraites du contenu textuel des documents en associant la finesse d'analyse d'une approche linguistique (extraction et structuration) à la capacité d'une approche statistique de traiter de gros corpus. L'approche statistique se base sur la fouille de données textuelles et principalement la technique de règles d'association. L'approche linguistique se base sur les syntagmes nominaux que nous considérons comme des entités textuelles plus susceptibles de représenter l'information contenue dans le texte que les termes simples. Elle explicite les contraintes linguistiques nécessaires à l'extraction des syntagmes nominaux et défini les rapports syntagmatiques entre les composantes d'un syntagme nominal. Ces relations syntagmatiques sont exploitées pour la structuration des syntagmes nominaux. Une mesure, appelée ``quantité d'information'', est proposée pour évaluer le pouvoir évocateur de chaque syntagme nominal, filtrer et comparer les syntagmes nominaux. Le modèle proposé démontre que la combinaison d'une approche statistique et d'une approche linguistique affine les connaissances extraites et améliore les performances d'un système de recherche d'information.
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Goodwin, Michaela. "The use of general anaesthetic for dental extractions in children : researching the complex causal networks and approaches to reducing need." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/the-use-of-general-anaesthetic-for-dental-extractions-in-children-researching-the-complex-causal-networks-and-approaches-to-reducing-need(eb277cce-f90a-4ce5-b62c-91873a7d2959).html.
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Dental decay remains a global issue but, in the UK, has become concentrated within the most vulnerable section of society, namely young children and the most deprived. When dental decay and subsequent infection become too severe, teeth may need to be extracted under General Anaesthetic. The aim of this work was to develop a greater understanding of the population of young children referred for a Dental General Anaesthetic (DGA) in the North West of England and to explore possible interventions that may positively impact on this group reducing the high number of children undergoing this procedure. A mixed methods approach was utilised, combining a broad scoping review, quantitative data collection and qualitative interviews. Individually these methods were used to develop a greater understanding of the issue and of the services, processes and patients involved in DGA. The methods were subsequently combined using triangulation to address potential preventative interventions that would be appropriate and acceptable to this group. Differences were observed between hospitals in treatment experiences of children across the North West of England. These included variations in the environment, hospital setting and time from referral to treatment, all of which were shown to impact on the child. The number of children experiencing a repeat DGA was also high and noted as an area that required further intervention. While DGA could be a distressing experience it was considered necessary and resulted in a positive outcome both in terms of oral health and a child’s quality of life. Improving oral health in young children who experience severe decay is a complex and challenging area. A number of interventions were identified that could reduce the need for extraction under DGA. These ranged from targeted interventions, linked to information provision and enablement to support those who are more at risk, to policy change with regard to excessive sugar in food and beverages that could have a broader impact across the population. In addition, DGA service re-designs are discussed including increased provision of prevention that may benefit children referred along this pathway and thereby reduce repeat DGA rates in the future.
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Fletcher, Harriet Rachael. "Microwave assisted hydrothermal extraction of carbohydrates from macroalgae and the impact of seasonal variation." Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/16939/.
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Macroalgae represent a diverse and abundant resource, containing an array of unique chemicals with useful properties. These chemicals include: alginate, a long chain carbohydrate with gelling properties; laminarin, a carbohydrate consisting of glucose residues, which is readily fermented; mannitol a sugar alcohol that can be used as an artificial sweetener and fucoidan, a sulphated polysaccharide famed for its biomedical properties. Their current use in industry is minor, with the main focus being as a food source and for alginate extraction. However, there is great potential for this feedstock in chemical and fuel production, especially for biorefinery development, which makes use of the whole resource by providing multiple products from one feedstock. Brown macroalgae offer the most promising option in Northern Europe, being the largest and most fast growing of the seaweed species, as well as being plentiful around the coast of the UK with the potential for cultivation alongside harvesting from wild stock. A potential barrier to the use of seaweed in industry is their seasonal variation in chemical content. In order to fully understand this, a study detailing the variations in carbohydrates, protein and ash, as well as a detailed study into the variation in composition and structure of fucoidan, identified as the most valuable of the potential extraction products due to its interest in the pharmaceuticals market, have been conducted. Three species of brown macroalgae, Fucus serratus (FS), Fucus vesiculosus (FV) and Ascophyllum nodosum (AN), have been analysed over a 12 month period. The results indicate that mannitol, laminarin and fucoidan are all highest at the end of the growing season in late summer and that ash, alginate and protein are highest during the winter months. The composition and structure of fucoidan is also seen to vary over the year, with FS having the highest sulphate content and results indicating a consistently more branched structure than was seen for FV and AN. In order to make the best use of the macroalgal feedstock, a three step hydrothermal microwave assisted biorefinery is proposed, with utilisation of the waste as a feedstock for fuel production or as a fertiliser being considered. For this, a sample of FS, identified in the seasonal variation study to have the best potential for chemical extraction, has been used. A low temperature step at 50°C in water firstly removes mannitol and a portion of the salts, followed by processing at 120°C in water to extract fucoidan and alginate. Alginate is precipitated from the extract with calcium carbonate and fucoidan with ethanol. The final step is processed at 120°C with sodium chloride to extract the remaining alginate from the residue. A mass balance of the proposed biorefinery shows that 90% of mannitol, 79% of fucoidan and 79% of alginate have been extracted during processing. A study into the quality of the fucoidan extracted by microwave heating is comparable to that extracted from the raw biomass by conventional means. A comparison of microwave and conventional heating shows the benefits in using microwaves, with decreased extraction temperature and a full energy balance of the system significant energy reductions associated with microwave heating on a laboratory scale.
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Singh, Neelam. "A Study of Human Impact on Sacred Groves in India." Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1153856401.
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Raycraft, Mary D. "Boomtown Attitudes and Perceptions Non-renewable Energy Extraction Regions:North Dakota, U.S.A., Oil Shale and Alberta, Canada, Oil Sands." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1527606796285623.
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Dekaki, Anouar. "Impact de l'utilisation d'un compost vert sur l'activité et la diversité de la microflore tellurique." Thesis, Paris Est, 2008. http://www.theses.fr/2008PEST0058/document.
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Le compostage est une technique de valorisation des déchets organiques en un produit stable et riche en matières humiques. Certains composts « verts » se sont révélés être de 2 à 3 fois plus efficaces sur la croissance des plantes que les composts classiques. Notre étude réalisée sur un compost fabriqué à partir de déchets végétaux a permis de suivre l’évolution de la densité et de la diversité de la microflore (bactéries, champignons) au cours du processus de maturation puis de tester l’impact de ce compost sur la diversité et l’activité de la microflore tellurique. Cette analyse a été effectuée par des techniques complémentaires : biochimiques (dosages enzymatiques), microbiologiques (cultures in vitro) et de biologie moléculaire (PCR-DGGE, Séquençage). Les résultats montrent qu’au cours de sa maturation, le compost étudié présente une baisse significative de son taux d’humidité et une augmentation sensible de son pH. Sa microflore subit une complète restructuration avec apparition de souches bactériennes susceptibles de dégrader des composés polluants comme les plastiques, les pesticides et les hydrocarbures. L’ajout de ce compost à deux types de sol présentant des propriétés physico-chimiques différentes, n’a pas montré de modifications importantes et durables de la diversité microbienne et fonctionnelle de celui-ci. Les causes de l’effet remarquable de ce compost sur la croissance végétale sont discutéesComposting is a technique of transformation organic waste in a stable product rich in organic materials. Some "green" compost proved to be from 2 to 3 times more benefit on the growth of the plants than traditional composts. The main of this study is to follow the evolution of density and diversity of the microflora (bacteria, fungi) during the process of maturation of green compost manufactured from vegetable wastes, and to investigate the impact of this compost on the diversity and the activity of the telluric microflora. This analysis was carried out by complementary techniques: biochemical (enzymatic activity), microbiological (in vitro cultures) and molecular biology (PCR-DGGE, DNA sequencing). The results show that during its maturation, the studied compost presents a significant decrease of its water content and an appreciable increase in its pH. The microflora undergoes a complete reorganization with appearance of bacterial strain suitable for degrade polluting compounds like the plastics, the pesticides and hydrocarbons. The addition of this compost with two types of soil presenting of the different physicochemical properties, did not show significant and durable modifications of the microbial and functional diversity of this one. The causes of the remarkable effect of this compost on the vegetable growth are discussed
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Bhujel, Nabina. "The impact of premature extraction of primary teeth on the subsequent need for orthodontic treatment." Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/5549/.
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Background: Premature Extraction of Primary Teeth (PEPT) is a common finding in any paediatric population. However, there are no systematic reviews or studies to date providing a reliable evidence base regarding PEPT and orthodontic need. Aims: To conduct a systematic review to systematically evaluate the effect of PEPT on malocclusion and to conduct a study in Bradford and Airedale district to explore this association. Materials and Methods: A thorough search strategy was developed and used to locate studies assessing the effect of PEPT on malocclusion and space loss. A methodological assessment was also carried out for included studies to assess risk of bias. A regional oral epidemiological survey of 12-year-old children in Bradford and Airedale was carried out in 2008/2009. As part of this oral health needs assessment, information on orthodontic need was also collected. A study group was formed of the children who had their orthodontic need assessed in the oral epidemiological survey and had their dental records available through the Salaried Dental Service (SDS). A multilevel logistic regression model was developed to explore the factors associated with orthodontic need. Results: Twenty-five studies were appraised for the systematic review. There was only one study assessing malocclusion following PEPT that fulfilled the predefined inclusion criteria which concluded that PEPT led to an increased incidence of malocclusion. Out of 366 children who were surveyed in the oral epidemiological survey from Bradford and Airedale, 116 had accessed SDS. Out of those, 107 children met the inclusion criteria. An increased total number of PEPT was positively associated with orthodontic need (odds ratio: 1.18, CI – 1.01 to 1.37). Conclusions: There was some evidence to suggest that malocclusion and thus orthodontic need was increased by the previous history of PEPT. The only predictor exhibiting significance was the total number of primary teeth lost.
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Gouali, Souhila. "Impact environnemental des anodes sacrificielles en aluminium." Caen, 2013. http://www.theses.fr/2013CAEN2026.
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En milieu marin, la protection des structures métalliques contre la corrosion peut être assurée par la technique de la protection cathodique en utilisant des anodes sacrificielles en aluminium. La solubilisation de ces dernières conduit à l'augmentation de la concentration en aluminium dans les eaux et les sédiments marins. Les résultats des tests de contamination par l'aluminium, en laboratoire, introduit sous forme de sel (sulfate ou chlorure d'aluminium) ou issu de la dissolution électrochimique d'une anode sacrificielle, dimensionnée pour un montage à trois électrodes à courant contrôlé ont montré une sorption de cet aluminium sur le sédiment naturel utilisé, quelle que soit l'origine de l'aluminium testé. Cet aluminium sorbé sur le sédiment naturel est mobile voire potentiellement remobilisable vers la phase aqueuse (piégé essentiellement dans la fraction réductible). Les sédiments deviennent alors une source potentielle de pollution. Les expériences réalisées sur les communautés microphytobenthiques ont montré clairement qu'elles sont affectées par l'exposition à l'aluminium. Cette sensibilité à l'aluminium de ces producteurs primaires est susceptible de constituer une menace pour tout le réseau trophique marinIn the marine environment, the protection of metallic structures against corrosion can be ensured by the technique of cathodic protection, thanks to sacrificial anodes made of aluminium. However, their consumption leads to increasing concentration of aluminium in waters and marine sediments. Tests featuring aluminium as a contaminant have been preceded in laboratory, using aluminium salts (aluminium sulfate and aluminium chloride) or aluminium produced by the dissolution of a sacrificial anode set up with three electrodes and controlled electric current. All results are displaying a sorption of aluminium, regardless of its source, onto the selected natural sediments. The sorbed aluminium is highly labile, and can even diffuse from sediments layers back to aqueous phase (trapped essentially in reducible fraction). Sediments turn then into a latent source of pollution. Experiments with microphytobenthos communities show clearly that they are affected by the exposure to aluminum. This sensitivity to aluminium of those primary producers constitutes a potential threat for the marine trophic network
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Czyzak, Zbigniew. "Impact du traitement hydro thermo dynamique sur les opérations de diffusion et d'extraction : applications au thé." La Rochelle, 2006. http://www.theses.fr/2006LAROS167.
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Boudreau, Mathieu. "Impact de la dilution opérationnelle sur le rendement métallurgique de l'or." Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/35842.
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Ce mémoire rend compte d’une étude avec un minerai aurifère pour quantifier l’effet de la dilution excédentaire sur l’extraction de l’or. Depuis une quinzaine d’années, une tendance d’augmentation de la profondeur des mines souterraines est observée au Canada et dans le monde. Lorsque ces exploitations souterraines atteignent des profondeurs supérieures à 1000 m, elles deviennent sujettes à de fortes pressions et tensions causées par la roche. Cependant, l’effet résultant sur l’extraction du minerai est difficilement quantifiable occasionnant une dilution opérationnelle excédentaire à celle planifiée. Le projet de maîtrise analyse l’impact de cette dilution excédentaire sur le traitement du minerai d’une mine d’or située dans la région de l’Abitibi (nord-ouest du Québec). Pour ce faire, deux types de dilution sont considérés : la roche stérile et le remblai. Les résultats du test de Bond et de données de cyanuration issues de la littérature illustrent dans quelle mesure le taux d’alimentation peut être augmenté pour mitiger l’effet de cette dilution excédentaire et la perte de production en or. La discussion étudie également les points positifs et négatifs du montage conçu pour l’automatisation de la cyanuration du projet.
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Zhang, Rui. "Impact of emerging technologies on the cell disruption and fractionation of microalgal biomass." Thesis, Compiègne, 2020. http://www.theses.fr/2020COMP2548.
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Ce travail de recherche se concentre sur l'extraction et le fractionnement des biomolécules à partir de microalgues par des traitements physiques: les champs électriques pulsés (CEP), les décharges électriques de hautes tensions (DEHT) et les ultrasons (US). Dans cette étude, trois espèces de microalgues Nannochloropsis sp., Phaeodactylum tricornutum (P. tricornutum) et Parachlorella kessleri (P. kessleri) ont été étudiées. Les espèces ont différentes formes cellulaires, structure et contenu intracellulaire. L'effet des techniques testées sur l'extraction des biomolécules a été mis en évidence à travers une analyse quantitative et qualitative: suivi du rendement des composés ioniques, des glucides, des protéines, des pigments et des lipides. Une étude comparative des traitements physiques (CEP, DEHT et US), à la même énergie, pour la libération des biomolécules intracellulaires à partir des trois espèces de microalgues, a permis de mieux comprendre les différents mécanismes de désintégration. Pour chaque microalgue, à la même énergie consommée, le traitement par DEHT s'est révélé le plus efficace en terme d'extraction des glucides, tandis que les US sont plus efficaces pour l'extraction des protéines et des pigments. Le traitement par CEP a été moins efficace en terme du rendement d’extraction. Cependant, la meilleure sélectivité (extraction des glucides) a été obtenue en utilisant les CEP ou les DEHT. Les prétraitements physiques (CEP, DEHT ou US) des suspensions plus concentrées suivis d'une homogénéisation haute pression (HHP) de suspensions diluées ont permis d'améliorer l'efficacité de l'extraction et de diminuer la consommation énergétique totale et le nombre de passages. Le prétraitement physique permet de réduire la pression mécanique de l’HHP, pour atteindre le même rendement d’extraction. Pour la valorisation maximale de la biomasse de microalgues, une procédure d'extraction assistée par DEHT (40 kV/cm, 1-8 ms) suivie de plusieurs étapes d'extraction aqueuses et non aqueuses semble être utile pour l'extraction sélective et le fractionnement de différentes biomolécules à partir de microalgues. Des effets significatifs du prétraitement HVED sur l'extraction par solvant organique des pigments (chlorophylles, caroténoïdes) et des lipides ont été observésThis research work focuses on extraction and fractionation of bio-molecules from microalgae using physical treatments: pulsed electric fields (PEF), high voltage electrical discharges (HVED) and ultrasonication (US) techniques. In this study, three microalgae species Nannochloropsis sp., Phaeodactylum tricornutum (P. tricornutum) and Parachlorella kessleri (P. kessleri) were investigated. These species have different cell shapes, structure and intracellular contents. The effects of tested techniques on extraction of bio-molecules have been highlighted in a quantitative and qualitative analysis by evaluating the ionic components, carbohydrates, proteins, pigments and lipids. A comparative study of physical treatments (PEF, HVED and US) at the equivalent energy input for release of intracellular bio-molecules from three microalgal species allowed us to better understand the different disintegration mechanisms. For each microalga at the same energy consumption, the HVED treatment proved to be the most efficient for extraction of carbohydrates, while the US treatment for extraction of proteins and pigments. In general, the smallest efficiency was observed for the PEF treatment. However, the highest selectivity towards carbohydrates can be obtained using the mild PEF or HVED technique. The preliminary physical treatments (PEF, HVED or US) of more concentrated suspensions followed by high pressure homogenization (HPH) of diluted suspensions allowed improving the extraction efficiency and decreasing the total energy consumption. The physical pretreatments permit to reduce the mechanical pressure of the HPH and number of passes, to reach the same extraction yield. For the maximum valorisation of microalgal biomass, extraction procedure assisted by HVED treatment (40 kV/cm, 1-8 ms) followed by aqueous and non-aqueous extraction steps seems to be useful for selective extraction and fractionation of different bio-molecules from microalgae. The significant effects of HVED pre-treatment on organic solvent extraction of pigments (chlorophylls, carotenoids) and lipids were also observed
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Mouloubou, Olsen. "Développements spectroscopiques pour l'étude de la matière organique du sol dans des extraits liquides, avec étude de son impact sur le comportement des métaux : application à un sol agricole amendé par du compost." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4733/document.
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L'évolution de la législation en matière de valorisation des déchets organiques incite au développement de filières de valorisation, parmi lesquelles le compostage présente un intérêt d'amendement pour les sols, lié notamment à la présence de substances humiques. La matière organique (MO) est une composante importante du sol en raison de son rôle dans les équilibres physiques, chimiques et biologiques, ainsi que par son implication dans le comportement des métaux et métaux traces (MMT). Les objectifs de cette thèse étaient de développer une approche méthodologique afin de caractériser la MO du sol (MOS) et étudier son évolution spatio-temporelle suite à l’apport d’un compost sur une année et 2 profondeurs, et d'approcher son impact sur le comportement des MMT. Une procédure d’extraction séquentielle en 4 étapes (eau, acide, soude, pyrophosphate) a été réalisée afin de fractionner la MOS. Des analyses quantitatives et qualitatives, ont été effectuées sur les extraits. La procédure de fractionnent chimique a permis de distinguer plusieurs catégories de composés organiques (labiles, fulviques et humiques plus ou moins aromatiques). Les analyses quantitatives et les réponses spectrales sur les extraits ont révélé un effet compost essentiellement les trois premiers mois après l’épandage et en été, avec un impact des paramètres climatiques au cours de l'année, mais pas au-delà de 15 cm. Le compost peut apporter au sol une charge supplémentaire en MMT, notamment potentiellement mobilisables, avec un risque de contamination modéré, mais non négligeable lié aux effets potentiels d’accumulation et de concentration sur le long termeThe evolution of the legislation regarding the valorization of biowaste (green manure) induces the development of valorization chains, among which amending soils with compost is of particular interest, due to the presence of humic substances. Organic matter (OM) is an important component of the soil due to its physical, chemical and biological participation, and its implication in the behaviour of metals and trace metals (MTM).The aims of this thesis were to develop a methodological approach to characterize OM of soil (SOM) and to study its spatiotemporal evolution over one year at two different depths following the addition of compost, and its impact on the behaviour of MTM. A 4-step sequential extraction procedure (water, acid, sodium hydroxide, pyrophosphate) was used to the SOM fractionation. Quantitative and qualitative analysis were applied on extracts. Solubilization kinetics of MTM was also carried out to refine the study of their mobility.The chemical fractionation procedure allowed distinguishing several classes of organic compounds (labile, fulvic and humic with various aromaticity). Quantitative analyzes and spectral responses of the extracts revealed an effect of the compost (organic carbon, metals, aromaticity and molecular weight compounds) essentially during the first three months after spreading and during the summer period, with a climate parameter effect during the year, but not beyond 15 cm of depth. Compost can bring to the soil an additional load of MTM, including potentially mobilized forms, with a moderate, but not negligible risk of contamination, due to the potential effects of accumulation and concentration over the long term
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Greenwood, M. F. D. "The fish populations of the Lower Forth Estuary, including the environmental impact of cooling water extraction." Thesis, University of Stirling, 2001. http://hdl.handle.net/1893/22856.
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The present study investigated the fish populations of the lower Forth Estuary, east Scotland. Cooling water extraction by the 2400 MW Longannet Power Station (LPS) inevitably removes a certain quantity of fish from the estuary, all of which experience mortality. The present study employed a sampling regime of greater intensity than previous studies to investigate the extent of mortalities from January 1999 - December 2000. Collections of fish impinged on intake screens were made eight times monthly, at LW or HW of spring or neap tides during the day or by night. Marine species dominated the assemblage of fish collected, with sprat, herring, and whiting contributing > 80% of total abundance. Sprat was twice as abundant as herring in 1999, while the proportions were very similar in 2000. Total abundance of all species collected in 1999 was estimated at 1. 09 x 107, while the value of 3.29 x 107 in 2000 was three times larger. These figures were the largest recorded among British estuarine and marine power stations, but were precisely the correct order based on an exponential relationship between total impingement and water abstraction rate established from data from other locations. Validation of the estimated total biomass of fish removed was given by comparison with the known total mass of all materials disposed to landfill. Statistical analysis of impingement data showed that tidal range and season were the most important environmental variables influencing the rate of removal of fish from the estuary. That light was not significant for most species is attributed to high levels of turbidity and the resulting low visibility by day and night. Demersal and benthic fish abundances collected from 1982 - 2000 in 30 annual trawls at three sites in the mid-lower Forth Estuary were analysed. Species tended to be present in greatest abundance at the most seaward of the sites. Patterns of seasonal abundance reflected those observed in the impingement study at LPS, and catches tended to be greatest at L W. Total species richness showed no significant trend over time, whilst total annual abundance of fish captured in trawls showed a significant negative trend. This was largely due to significant declines in the two most abundant species, namely whiting and eel pout, attributable in the latter case to increasing temperatures. Changes in the ichthyofaunal composition were largely driven by whiting, eel pout, cod and plaice. Eight of ten common species showed no significant trend in abundance over the length of the time series, suggesting them to perhaps be at equilibrium densities. Quantities of commercially fished species above minimum landing size limits that were removed by LPS were very low, and restricted to herring and occasional whiting. The quantity of juveniles that could have recruited into the fished populations was expressed as equivalent adults. The values were larger than any previously reported in the UK, primarily due to the quantities of juvenile fish impinged being greater than at any other British power station, and the importance of the Forth as a nursery area for marine species. It was concluded that LPS is the dominant UK power station in terms of magnitude of impingement losses. It may be prudent to consider a precautionary approach to mitigate losses, and to this end options for reduction of the magnitude of impingement are discussed.
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Wang, Lu. "Valorization of apple by-products by the extraction and purification of polyphenols : impact of the ultrasound." Thesis, Compiègne, 2019. http://www.theses.fr/2019COMP2509/document.
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Cette thèse porte sur l'intensification de l'extraction de polyphénols à partir de produits à base de pomme (chair, peau et marc) par ultrasons (US) et sur la purification d'extraits de peau de pomme par adsorption/désorption et technologie membranaire. L'extraction sélective des polyphénols issus des produits de la pomme a été analysée. Les données obtenues ont démontré la possibilité d’une régulation fine de l’extraction sélective de la matière soluble, de la catéchine et des composés polyphénoliques totaux en utilisant différentes températures, protocoles UAE, mélanges éthanol/aqueux. La sélectivité de l'extraction de la catéchine dépendait également du type de tissu (chair, peau ou marc) et de la variété de pomme (verte ou rouge). Le phénomène de cavitation généré par les ultrasons pourrait augmenter l'extraction de composants précieux des pelures de fruits en endommageant les membranes cellulaires des échantillons et en accélérant ainsi le transfert de chaleur et de masse. D’autre part, les solvants eau-gaz pourraient améliorer l'efficacité d'extraction des polyphénols des peaux de pomme en renforçant le phénomène de cavitation généré par les ultrasons. L'efficacité de la purification de polyphénols d'extraits de pelure de pomme par adsorption/désorption assisté par ultrasons (adsorbant polyaromatique Amberlite XAD-16) et par électrofiltration sur membrane a été mise en évidence. Les données obtenues ont démontré que la sonication facilitait significativement la cinétique d’adsorption, la capacité d’adsorption accrue et augmentation de l’énergie d’activation de l’adsorption des polyphénols. En outre, le taux de désorption a été positivement affecté par la sonication au cours de l'étape d'adsorption. Par ailleurs, les résultats ont montré que l’électrofiltration sur membrane permettait de purifier les polyphénols dans l’espace anodique (+) et d’obtenir un volume plus important de filtratsThis thesis focuses on the intensification of polyphenols extraction from apple products (flesh, peel, and pomace) by ultrasound (US) and the purification of apple peel extracts by adsorption/desorption and membrane technology. The selective extraction of phenolic contents from apple products has been analyzed. The obtained data evidenced the possibility of fine regulation of selective extraction of soluble matter, catechin and total polyphenolic compounds using different temperatures, ultrasound-assisted extraction (UAE) protocols, ethanol/aqueous mixtures. The selectivity of catechin extraction was also depended on the type of the tissue (flesh, peel or pomace) and apple variety (green or red). The cavitation phenomenon generated by ultrasound could increase extraction of valuable components from fruit peels by damaging cell membranes of samples and accelerating heat and mass transfer by disrupted cell walls of samples. Meanwhile, the gas water solvents could enhance the extraction efficiency of polyphenols and antioxidant activity from apple peels by enhancing cavitation phenomenon generated by ultrasound. The efficiency of polyphenols purification from apple peel extracts with adsorption/desorption process by ultrasound treatment with the polyaromatic amberlite adsorbent XAD-16 and with membrane electro-filtration were studied. The obtained data demonstrated that the sonication significantly facilitated adsorption kinetics and increased activation energy of polyphenols adsorption. In addition, the desorption ratio was positively affected by the sonication during the adsorption step. On the other hand, the results demonstrated that the membrane electro-filtration allowed the purification of polyphenols in the anode (+) space and obtaining larger volume of filtrates
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Mauro, Manuela. "Mining extraction in the ocean depths: a baseline to understand and reduce acoustic impact on biodiversity." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/144131.
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[ES] A lo largo de la historia, el hombre ha explotado los recursos minerales de la tierra para su supervivencia y desarrollo tecnológico sin un equilibrio con su regeneración. Dado el crecimiento de la población mundial y la reducción de recursos, el hombre comenzó a buscar nuevos depósitos que se encontraron en la década de 1960 en las profundidades de los océanos. Con estos, la humanidad empezò a pensar en extraer los minerales de estos depósitos y esto llevò al nacimiento de Deep Sea Mining (DSM). Las consecuencias de las actividades mineras en las profundidades del mar no se conocen realmente y los efectos pueden ser diferentes: contaminación acústica, contaminación lumínica, contaminación química, destrucción del hábitat, fragmentación del hábitat y pérdida de especies que son la base de muchos sistemas vitales. El impacto acústico de estas actividades puede tener importantes consecuencias en las especies marinas, aunque este es el tema más ignorado. El propósito de este proyecto de doctorado fue proporcionar una comprensión básica de los posibles impactos acústicos del DSM en la biodiversidad antes de que comiencen estas actividades. Para hacer esto, el proyecto de doctorado se organizó en varios pasos. Primero, durante un experimento indoor, se analizaron las respuestas bioquímicas en invertebrados sometidos a estrés acústico, Arbacia lixula y Mytilus galloprovincialis. Los resultados demostraron efectos significativos en la actividad de citotoxicidad, expresión de heat shock protein (HSPs) y actividades enzimáticas (esterasas, fosfatasas alcalinas, peroxidasas) en el líquido celomático de los erizos de mar sometidos a estrés acústico. También se observaron efectos significativos en el nivel de glucosa, la citotoxicidad y las actividades enzimáticas (esterasa, fosfatasa alcalina, peroxidasa) de la glándula digestiva del mejillón. En segundo lugar, se analizaron las respuestas bioquímicas de vertebrados e invertebrados sometidos in-situ a la emisión de watergun: Chromis chromis, Holothuria tubulosa y Arbacia lixula. Se encontraron efectos significativos sobre los niveles de cortisol en peces y las actividades enzimáticas (esterasas, fosfatasas alcalinas, peroxidasas y superoxide dismutasas) en membrana peristomial de erizo de mar. Además, las respuestas bioquímicas enzimáticas analizadas en los fluidos celómicos de los equinodermos fue significativa solo por A. lixula y solo en la activade peroxidasica. Tercero se estudiaron los cambios de comportamiento en las condiciones experimentales en juveniles de Sparus aurata sometidos a 4 frecuencias de emisión acústica diferentes. Este experimento demostró que solo las bajas frecuencias tuvieron efectos en todas las respuestas comportamental: altura de natación, motilidad y dispersión del grupo. Sobre la base de los datos de comportamiento obtenidos in vivo en peces jóvenes, se creó un modelo numérico para predecir los impactos de diferentes frecuencias de emisión acústica. Utilizando los resultados obtenidos y la bibliografía científica, se propuso un primer estándar técnico que es útil para la minería.[CAT] A lo llarc de l'historia, l'home ha explotat els recursos minerals de la terra per a la seua supervivencia i desenroll tecnologic sense un equilibri en la seua regeneracio. Donat el creiximent de la poblacio mundial i la reduccio de recursos, l'home escomençà a buscar nous deposits que se trobaren en la decada de 1960 en les fondaries dels oceans. En estos, l'humanitat empezò a pensar en extraure els minerals d'estos deposits i aço llevò al naiximent de Deep Sea Mining (DSM). Les conseqüencies de les activitats mineres en les fondaries del mar no se coneixen realment i els efectes poden ser diferents: contaminacio acustica, contaminacio lluminica, contaminacio quimica, destruccio de l'habitat, fragmentacio de l'habitat i perdua d'especies que son la base de molts sistemes vitals. L'impacte acustic d'estes activitats pot tindre importants conseqüencies en les especies marines, encara que este es el tema mes ignorat. El proposit d'este proyecte de doctorat fon proporcionar una comprensio basica dels possibles impactes acustics del DSM en la biodiversidad abans de que escomencen estes activitats. Per a fer aço, el proyecte de doctorat s'organisà en varis passos. Primer, durant un experiment indoor, s'analisaren les respostes bioquimiques en invertebrats somesos a estrés acustic, Arbacia lixula i Mytilus galloprovincialis. Els resultats demostraren efectes significatius en l'activitat de citotoxicidad, expressio d'heat shock protein (HSPS) i activitats enzimáticas (esterasa, fosfatasas alcalina, peroxidasas) en el liquit celomático dels capellanets de mar somesos a estrés acustic. Tambe s'observaren efectes significatius en el nivell de glucosa, la citotoxicidad i les activitats enzimáticas (esterasa, fosfatasa alcalina, peroxidasas) de la glandula digestiva de la clochina. En segon lloc, s'analisaren les respostes bioquimiques de vertebrats i invertebrats somesos in-situ a l'emissio de watergun: Chromis chromis, Holothuria tubulosa i Arbacia lixula. se trobaren efectes significatius sobre els nivells de cortisol en peixos i les activitats enzimáticas (esterasas, fosfatasas alcalines, peroxidasas y superoxide dimutases) en peristomes de capellanet de mar. Ademes, les respostes bioquimiques enzimáticas analisades en els decorreguts celómicos dels equinoderms fon significativa nomes per A. lixula i nomes en l'activade peroxidasica. Tercer s'estudiaren els canvis de comportament en les condicions experimentals en jovenils de Sparus aurata somesos a 4 freqüencies d'emissio acustica diferents. Este experiment demostrà que nomes les baixes freqüencies tingueren efectes en totes les respostes comportamental: alçada de natacio, motilidad i escampada del grup. Sobre la base de les senyes de comportament obtinguts in vivo en peixos jovens, se creó un model numeric per a predecir els impactes de diferents freqüencies d'emissio acustica. Utilisant els resultats obtinguts i la bibliografia cientifica, se propongue un primer estandart tecnic que es util per a la mineria.
[EN] Throughout history, man has exploited the earth's mineral resources for its survival and for technological development without regard for their regeneration. Given the growth of the world population and given the fall in resources, man started looking for new deposits, which were found in 1960s in the ocean depths. Humankind then began to consider extracting minerals from these deposits and this gave origin to Deep Sea Mining (DSM). The consequences of mining activities in the deep sea are not entirely known and the effects can be varied: noise pollution, light pollution, chemical pollution, habitat destruction, habitat fragmentation and the loss of species which we consider the basis of many life systems. The acoustic impact of these activities could have significant consequences on marine species; nevertheless, this has been the most overlooked issue to date. The aim of this PhD project was to provide baseline knowledge of possible acoustic impacts of DSM on biodiversity before mining begins. In order to do this, the PhD project was organised into 3 different stages. First, during an indoor experiment, the biochemical responses of invertebrates Arbacia lixula and Mytilus galloprovincialis subjected to acoustic stress were analysed. The results showed significant changes in cytotoxicity activity, expression of heat shock proteins (HSPs), and enzyme activities (esterases, alkaline phosphatases, peroxidases) in the coelomic fluid of sea urchins subjected to acoustic stress. Significant effects were also observed in glucose levels, cytotoxicity and enzyme activities (esterase, alkaline phosphatase, peroxidase) in the digestive gland of the mussel. Second, the biochemical responses of vertebrates and invertebrates subjected in-situ to watergun emission were analysed: Chromis chromis, Holothuria tubulosa and Arbacia lixula. Significant effects on fish cortisol levels and on enzyme activities in sea urchin peristomes were found. Furthermore, the enzyme biochemical responses analysed in the coelomic fluids of echinoderms showed significant effects only in A. lixula sea urchin and only in peroxidase activity. Third, behavioural changes in experimental conditions were studied in juveniles of Sparus aurata subjected to 4 different acoustic emission frequencies. This experiment showed that only low frequencies had effects on all the behavioural responses analysed: swimming height, motility and dispersion of the group. Based on behavioural data obtained in vivo on juvenile fish, a numerical model was created to predict the impacts of different acoustic emission frequencies. Using the results obtained and literature, a first technical standard useful for mining activities was drawn up.
The study of the Section 3.3 was supported by grants from MIUR (Ministry of Education, University and Research), Fondo Finalizzato alla Ricerca di Ateneo (FFR, 2018-2021) to M.V. and by the CNR research project: IMPLEMENTATION OF THE SOS CONVENTION - Offshore Platforms & Impacts between MATTM and CNR-DTA, (Capo Granitola, Campobello di Mazara) Work Package E: Indepth technical and scientific evaluation of the effects on marine ecosystems of airgun technologies and the effects of a watergun The study of the Section 3.4 study was conducted in the framework of the PhD program in Mediterranean Biodiversity XXXII cycle (International) of the University of Palermo. I. Perez-Arjona, M. Bou-Cabo and V. Espinosa acknowledge the financial support of the European Comission -project 11.0661/2018794607/SUB/ENV.C2. Risk-based Approaches to Good Environmental Status (RAGES). The other founding supports come from PhD Innovative with Industrial Characterization PON 2014-2020 and the projects CAIMAR Joint Laboratory Italy-Argentina (Laboratori Congiunti Bilaterali Internazionali of the Italian National Reseach Council, 2017-2019) and BOSS – Study of bioacoustics and applications for the sustainable exploitation of marine resources (Projects of major importance in the Scientific and Technological Collaboration Executive Programmes, funded by the Italian Ministry of Foreign Affairs and International Cooperation).
Mauro, M. (2020). Mining extraction in the ocean depths: a baseline to understand and reduce acoustic impact on biodiversity [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/144131
TESIS