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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
491

Responsabilité sociétale et ancrage territorial d'une entreprise de services urbains : le cas de Lyonnaise des Eaux / Corporate social responsibility and territorial embeddedness of a utilities company : Lyonnaise des Eaux case study

Batisse, Julien 10 July 2015 (has links)
Dans un contexte de réflexions contemporaines sur la durabilité des services urbains d’eau potable, nous nous intéressons à la stratégie de responsabilité sociétale de Lyonnaise des Eaux comme contribution à la mise en mots et mise en œuvre du développement durable dans ce secteur d’activité. L’objectif de ce travail est d’analyser et questionner la stratégie de responsabilité sociétale de l’entreprise (RSE) pour y mettre en lumière d’une part ses causes, processus, finalités, et en comprendre, d’autre part, les impacts sur l’ancrage territorial de l’entreprise. Le mouvement de territorialisation de la RSE s’exprime dans un processus d’interaction global-local aboutissant à la régionalisation de la stratégie RSE de Lyonnaise des Eaux et à son incarnation locale sous la forme de projets développement durable. A partir de l’exemple de la gestion de l’eau potable dans la métropole bordelaise, nous avons étudié et mené deux projets de développement durable au sein de Lyonnaise des Eaux : le premier centré sur la gestion des usagers en situation de précarité hydrique ; le second portant sur l’accompagnement des usagers à la gestion durable de leur consommation d’eau. L’exploration des conditions territoriales de faisabilité de ces projets met en lumière les possibilités offertes à l’entreprise de répondre aux enjeux du territoire en limitant l’impact lié à son activité et de générer les ressources spécifiques nécessaires à son intégration dans des dispositifs locaux d’innovation. L’analyse spatiale de la responsabilité sociétale montre qu’elle est aussi l’interface négociée de l’adaptation et de l’action territorialisée de l’entreprise aux différents échelons. / In a context of contemporary reflections on the sustainability of urban water utilities, we focus on Lyonnaise des Eaux’s corporate social responsibility strategy as a contribution to putting into words and implementing sustainable development in this sector. This work aims at analyzing on the one hand the causes, processes, goals of Lyonnaise des Eaux CSR strategy and understanding on the other hand the impact of these strategies on the company’s territorial embeddedness. CSR's territorial impetus is expressed via a global-local interaction process leading to the regionalization of Lyonnaise des Eaux CSR strategy and, its local embodiment through sustainable development projects. Based on the example of water management in the Bordeaux metropolis, we have studied and conducted two sustainable development projects within the company, one focused on water poverty management and the other focused on sustainable management of domestic water consumption. Exploring the feasibility conditions of these CSR projects highlights the opportunities for the company to meet the challenges of the territory by limiting the impact associated with its business or generate specific resources necessary for its integration into local innovation systems. The territorial approach of corporate responsibility strategy shows that it also appears as a negotiated interface used by Lyonnaise des Eaux for its adaptation and action at different scales.
492

Quasi real-time model for security of water distribution network / Modèle quasi-temps réel pour la sécurité des réseaux d’alimentation en eau potable

Ung, Hervé 05 February 2016 (has links)
Le but de cette thèse est de modéliser la propagation d’un contaminant au sein d’un réseau d’eau potable muni de capteurs temps réel. Elle comporte les trois axes de développement suivant: la résolution des équations de transport, celle du problème d’identification des sources de contamination et le placement des capteurs.Le transport d’un produit chimique est modélisé dans un réseau d’eau potable par l’équation de transport réaction 1-D avec l’hypothèse de mélange parfait aux noeuds. Il est proposé d’améliorer sa prédiction par l’ajout d’un modèle de mélange imparfait aux jonctions double T et d’un modèle de dispersion prenant en compte un profil de vitesse 3-D et la diffusion radiale. Le premier modèle est créé à l’aide d’un plan d’expériences avec triangulation de Delaunay, de simulations CFD, et de la méthode d’interpolation krigeage. Le second utilise les équations adjointes du problème de transport avec l’ajout de particules évoluant à l’aide d’une marche aléatoire, cette dernière modélisant la diffusion radiale dans la surface droite du tuyau.Le problème d’identification des sources consiste, à l’aide de réponses positives ou négatives à la contamination des noeuds capteurs, à trouver l’origine, le temps d’injection et la durée de la contamination. La résolution de ce problème inverse est faite par la résolution des équations de transport adjointes par formulation backtracking. La méthode donne la liste des sources potentielles ainsi que le classement de celles-ci selon leur probabilité d’être la vraie source de contamination. Elle s’exprime en fonction de combien, en pourcentage, cette source potentielle peut expliquer les réponses positives aux capteurs.Le placement des capteurs est optimisé pour l’identification des sources. L’objectif est la maximisation du potentiel de détection de la véritable source de contamination. Deux résolutions sont testées. La première utilise un algorithme glouton combiné à une méthode de Monte Carlo.La seconde utilise une méthode de recherche locale sur graphe.Finalement les méthodes sont appliquées à un cas test réel avec dans l’ordre : le placement des capteurs, l’identification de la source de contamination et l’estimation de sa propagation. / The aim of this thesis is to model the propagation of a contaminant inside a water distribution network equipped with real time sensors. There are three research directions: the solving of the transport equations, the source identification and the sensor placement. Classical model for transport of a chemical product in a water distribution network isusing 1D-advection-reaction equations with the hypothesis of perfect mixing at junctions. It isproposed to improve the predictions by adding a model of imperfect mixing at double T-junctions and by considering dispersion effect in pipes which takes into account a 3-D velocity profile. The first enhancement is created with the help of a design of experiment based on the Delaunay triangulation, CFD simulations and the interpolation method Kriging. The second one uses the adjoint formulation of the transport equations applied with an algorithm of particle backtracking and a random walk, which models the radial diffusion in the cross-section of a pipe.The source identification problem consists in finding the contamination origin, itsinjection time and its duration from positive and negative responses given by the sensors. The solution to this inverse problem is computed by solving the adjoint transport equations with a backtracking formulation. The method gives a list of potential sources and the ranking of thosemore likely to be the real sources of contamination. It is function of how much, in percentage, they can explain the positive responses of the sensors.The sensor placement is chosen in order to maximize the ranking of the real source of contamination among the potential sources. Two solutions are proposed. The first one uses agreedy algorithm combined with a Monte Carlo method. The second one uses a local search method on graphs. Finally the methods are applied to a real test case in the following order: the sensor placement, the source identification and the estimation of the contamination propagation.
493

Exposition prénatale hydrique aux perturbateurs endocriniens et issues de grossesse / Prenatal exposure to endocrine disruptors in drinking-water and pregnancy outcomes

Albouy-Llaty, Marion 11 April 2014 (has links)
L'eau potable comme source d'exposition aux perturbateurs endocriniens (PE) est peu étudiée, notamment chez les personnes vulnérables comme les femmes enceintes, dont les modes de consommation d'eau évoluent pendant la grossesse. Les objectifs de la thèse étaient i) déterminer s'il existe une relation entre l'exposition prénatale hydrique aux PE, et la prévalence d'enfants ayant un petit poids de naissance pour leur âge gestationnel (PPAG) ou prématurés tenant compte des facteurs socio-économiques ; ii) estimer pour la première fois en France les usages de l'eau potable pendant la grossesse.Trois études épidémiologiques issues d'une cohorte rétrospective, ont été réalisées auprès de 13654 femmes enceintes ayant accouché dans les Deux-Sèvres entre 2005 et 2010. Une exposition hydrique aux doses moyennes de nitrates au deuxième trimestre augmentait le risque de PPAG, particulièrement chez les femmes résidant dans des quartiers favorisés. En revanche, aucune relation significative entre une exposition prénatale hydrique à la 2-hydroxyatrazine et le risque de prématurité n'a été montrée.Les usages de l'eau potable ont été évalués par un questionnaire administré en face-à-face auprès de 132 femmes enceintes françaises de la cohorte prospective EDDS. La consommation d'eau pendant la grossesse était stable et comprenait plus d'eau du robinet que d'eau embouteillée. Afin de reconstituer la dose absorbée en PE, ces résultats devront être couplés à des dosages environnementaux et dans les matrices biologiques.Ces travaux confirment l'intérêt de l'approche interdisciplinaire en santé environnementale et celui de l'éducation relative à la santé environnementale. / Drinking-water as a source of exposure to endocrine disruptors, particularly in pregnant women whose water-use habits change during pregnancy, has seldom been studied. Our objectives were i) to study the possible relationship between prenatal exposure to endocrine disruptors in drinking water, socioeconomic factors and prevalence of neonates born small-for-gestational-age (SGA) or preterm birth ; ii) to estimate for the first time in France the water-use habits of pregnant women throughout pregnancy.Three epidemiologic studies from a retrospective cohort were carried out on 13,654 pregnant women who gave birth in Deux-Sèvres (France) between 2005 and 2010. An exposure to moderate dose of nitrates in drinking-water increased SGM risk, particularly for women living in less deprived areas. No relationship between prenatal exposure to 2-hydroxyatrazin in drinking-water and preterm birth risk was found.Water-use habits during pregnancy were assessed with a questionnaire on 132 women from the EDDS prospective cohort. Water ingestion was stable during pregnancy and tap water predominated over bottled water. In order to reconstitute the dose of pollutant intake from water, the results of this estimation by questionnaire will need to be merged with analytical dosages in waters and biological matrices.Our study confirms the interest of an interdisciplinary approach to environmental health and the key importance of education in that field.
494

Performance of aged PAC suspensions in a hybrid membrane process for drinking water production

Stoquart, Céline 18 August 2014 (has links)
Les procédés membranaires hybrides (PMH) allient la filtration membranaire basse pression à l’usage du charbon actif en poudre (CAP). Afin de diminuer les coûts opérationnels du procédé, il a été proposé de laisser vieillir le CAP dans le PMH et donc de minimiser le dosage de CAP frais. Peu d’information est disponible quant à la capacité résiduelle d’adsorption de suspensions de CAP âgées. L’importance relative de l’adsorption et de la biodégradation dans les réacteurs à CAP âgés sur le traitement des composés dissous est inconnue, ce qui empêche notamment l’optimisation du procédé. <p><p>Le principal objectif de ce projet de recherche est de décrire la performance du contacteur à CAP du PMH pour l’enlèvement de l’azote ammoniacal, du carbone organique dissous (COD), du COD biodégradable (CODB) et des micropolluants. Dans ce projet, l’emphase est placée sur l’opération du PMH avec de hauts temps de rétention de CAP. <p><p>La première phase de ce projet a consisté en une série de développements méthodologiques, base nécessaire à l’étude du CAP âgé. Des méthodes permettant la quantification de la biomasse hétérotrophe et nitrifiante colonisant le CAP âgé ont mis en évidence des densités de biomasse similaires à celle du charbon actif en grain en surface de filtre biologiques. L’irradiation aux rayons gamma a été démontrée comme une méthode adéquate pour produire des témoins abiotiques à partir de CAP de 10 et de 60 jours.<p><p>La seconde partie de cette étude s’est concentrée sur la démonstration de l’efficacité du PMH pour l’enlèvement de l’azote ammoniacal, du COD, ainsi que d’un mélange de micropolluants. Les cinétiques d’enlèvements ayant lieu au sein de des contacteurs à CAP ont été simulées en laboratoire sous diverses conditions (température, concentration en CAP, âge de CAP, matrice d’eau variable, temps de contact). Deux modèles cinétiques prédisant l’enlèvement de l’azote ammoniacal et du COD dans le PMH ont été développés sur base des simulations en laboratoire suivies sur CAP neuf, colonisé et abiotique. <p><p>De manière générale, les travaux réalisés au cours de ce doctorat ont mis en évidence le rôle majeur de l’adsorption résiduelle sur l’enlèvement de la contamination dissoute. Alors que l’enlèvement d’azote ammoniacal a majoritairement eu lieu par nitrification, le COD et les micropollutants sont principalement adsorbés sur le CAP colonisé. Il a aussi été montré que la capacité d’adsorption résiduelle des suspensions de CAP âgées peut agir en tampon, permettant de faire face à une augmentation soudaine de la concentration en azote ammoniacal, en COD ou en micropolluants. Le suivi des cinétiques d’enlèvement a permis de démontrer que la concentration, l’âge de CAP et le temps de rétention hydraulique (TRH) sont trois paramètres clefs pour l’optimisation du procédé. D’un point de vue économique, un TRH inférieur à 15 min est néanmoins désiré pour limiter les coûts du procédé. Par ailleurs, l’intérêt économique associé à l’augmentation de l’âge du CAP peut-être atténué par le besoin d’augmenter la concentration en CAP si l’adsorption est le mécanisme visé. De façon générale, ce projet démontre qu’une optimisation à l’échelle pilote du procédé est nécessaire car les objectifs de traitement, la qualité de l’eau à traiter et le fait que les 3 paramètres d’opération soient inter-reliés complexifient l’optimisation du PMH. Étant donné l’impact du TRH sur le coût du PMH, de futures recherches devraient viser à l’optimisation du mélange. <p>Hybrid membrane processes (HMPs) couple membrane filtration with powdered activated carbon (PAC). In HMPs, low-pressure membranes ensure an efficient particle removal, including protozoan parasites such as Cryptosporidium, while the PAC contactor is devoted to the removal of dissolved compounds. Such processes are emerging as a promising alternative to conventional treatment chains, which no longer allow the drinking water facilities to comply with increasingly stringent regulations on the treated water quality. To decrease the operating costs associated with virgin PAC consumption, it was suggested to let the PAC age in the PAC contactor of the process. Until now, the potential of using aged PAC in HMPs has been demonstrated for ammonia and DOC removal, but the potential to remove micropollutants remains unknown. It is suggested that the biological activity in aged PAC contactors contributes significantly to the removal of the dissolved compounds. Yet, neither the extent of the biomass on the aged PAC, nor the residual adsorption capacity, was quantified. No study focused on discriminating the mechanisms responsible for the treatment when using aged PAC suspensions. Most of the data published on HMPs using aged PAC were gathered at pilot scale under warm water conditions, yet the efficiency of the process is most likely sensitive to temperature changes. There is currently little information available on the efficiency of HMPs under cold water conditions. This lack of information hinders the optimization of the HMP, leading to sub-optimal usage of aged PAC.<p><p>The main objective of this research project is to describe the performance of the PAC contactor of HMPs in removing ammonia, dissolved organic carbon (DOC), biodegradable DOC (BDOC) and micropollutants. In particular, emphasis was placed on the operation of the HMP under high PAC residence times. On a more detailed level, the objectives of this project were (1) to develop and compare methods to quantify the biomass developed on aged PAC, (2) to develop a method to produce an abiotic control for aged PAC, (3) to characterize the removal kinetics of ammonia, DOC, BDOC and micropollutants occurring in the carbon contactor of an HMP, (4) to evaluate the impact of water temperature on the performance of the carbon contactor of an HMP, (5) to discriminate the relative importance of adsorption versus biological oxidation as mechanisms responsible for ammonia, DOC and micropollutants removal in the PAC contactor of an HMP, and finally (6) to differentiate the relative importance of the hydraulic retention time (HRT), the PAC age and the PAC concentration as key operating parameters on the optimization of the performance of the PAC contactor of an HMP.<p><p><p>To set the basis on the study of aged PACs, the first part of this research project consisted in methodological developments i) to quantify the heterotrophic and nitrifying biomass colonizing aged PAC, and ii) to create a reliable abiotic control of the colonized PAC, which is required for discriminating the mechanisms occurring on aged PAC. Heterotrophic and nitrifying biomass quantifying methods developed for colonized granular activated carbon (GAC) were successfully adapted to the aged PAC. The preferred methods were the potential 14C-glucose respiration (PGR) rate and the potential nitrifying activity (PNA), as they quantify the active heterotrophic and nitrifying biomass, which is most likely responsible for the depletion of BDOC and ammonia. An alternative method to the PGR, the potential acetate uptake (PAU) rate, was developed to alleviate the logistical and budgetary issues associated with the utilization of radio-labeled glucose. The densities (per gram of dry PAC) of both active heterotrophic and nitrifying biomasses were found comparable to that of the GAC sampled from the surface of a biological GAC filter. The gamma-irradiation was demonstrated as a reliable method to produce abiotic samples from soils, and was therefore chosen to produce abiotic colonized PAC samples in this project. In order to determine the optimized dosage of gamma-rays, increased doses were applied on PAC samples. Heterotrophic plate counts and methylene blue adsorption kinetics were used to determine respectively the lowest gamma ray dose required to inhibit the bacterial activity, and the highest dose that could be applied without affecting the aged PAC adsorption capacity and kinetics. Refractory DOC (RDOC) adsorption kinetics confirmed the accuracy of the dose chosen as the adsorptive behavior of the aged PAC was not affected. PGR rates were decreased 83% at the optimized dose. The gamma-irradiation method was therefore proven efficient and used in the following work phases of this research.<p><p>The second part of this study focused on the removal of ammonia, DOC and a mixture of micropollutants. Firstly, the PAC contactor of an HMP was simulated at lab-scale to monitor ammonia removal kinetics. Three PAC concentrations (approximately 1-5-10 g/L) of three PAC ages (0-10-60 days) were tested at two temperatures (7-22°C), in settled water with ambient influent condition (100 µg N–NH4/L) as well as under a simulated peak pollution scenario (1000 µg N–NH4/L). The kinetics evidenced that ammonia flux at pilot scale limited biomass growth (HRT = 67 min). In contrast, PAC colonization was not limited by the available surface and thus, PAC concentration was not a key operating parameter under the colonizing conditions tested (5-10 g/L). Ammonia adsorption was significant onto virgin PAC but the ammonia nitrification was crucial to reach complete ammonia removal at 22°C. When using colonized PAC, the 60-d PAC offered a better resilience to temperature decreases (78% at 7°C) as well as lower operating costs than the 10-d PAC (<10% at 7°C). Significant ammonia adsorption was also evidenced on 60-d PAC suspension, most probably due to PAC and the presence of suspended solids, but not on 10-d PAC. Adsorption and nitrifying activity were superior on 60-d PAC than on 10-d PAC at 7°C. In case of peak pollution, the process was most probably phosphate-limited but a mixed adsorption/nitrification still allowed 50% ammonia removal on 10-d and 60-d PAC at 22°C. A kinetics based model was developed to predict ammonia removals and to determine the relative importance of the adsorption and nitrification on colonized PAC under the conditions tested. <p><p>DOC, BDOC and RDOC removals occurring in the PAC contactor of an HMP were also simulated at lab-scale. Similar conditions to that of the ammonia removal kinetics were tested. The initial ammonia concentration remained untouched in the water matrices (settled water and raw water) but the BDOC-to-DOC ratio was altered by pre-ozonation (0 to 1.5 g O3/g C). The 10-d and 60-d abiotic controls were used to discriminate DOC adsorption from biodegradation. DOC biodegradation contributed marginally to DOC removal in the investigated conditions and DOC adsorption was increased at higher temperature. An original model integrating the PAC age distribution was developed to predict DOC removal in aged PAC contactors operated at steady-state. At a mean PAC residence time of 60-d, the younger PAC fraction (25-d and less) was primarily responsible for DOC adsorption (> 80%). This fraction represents 34% of the mass of PAC in the contactor. When using a water matrix with a higher initial DOC concentration (raw water) or a lower affinity for PAC (pre-ozonated settled water), the residual adsorption capacity of that older fraction was proven useful. <p><p>Lastly, a mixture of micropollutants (atrazine, deethylatrazine (DEA), linuron, microcystin, caffeine, carbamazepine, sulfamethoxazole, diclofenac, progesterone and medroxyprogesterone) was spiked at environmentally relevant concentrations (from 130 ng/L to 33 µg/L) in settled water (0 and 0.85 gO3/gC). The micropollutants concentration depletion was monitored over a period of 7h to 48 h on 1 g/L of 0-d, 10-d, 60-d PAC and gamma-irradiated 60-d PAC. Even in presence of NOM, the spiked micropollutants were rapidly adsorbed on aged PAC. No biodegradation was observed. Removals superior to 95% were reached within 5 minutes, and direct competition with NOM did not impact the efficiency of the process when micropollutants were spiked at environmentally relevant concentrations. Therefore, HMPs operated to remove DOC and ammonia can control transient micropollutant pollution and comply with the World health Organization recommendations for atrazine (2 µg/L) and microcystin (1 µg/L). However, the stricter European regulations for atrazine and DEA (0.1 µg/L) could not be met with 10-d and 60-d PAC under the operating conditions tested. Reaching such strict treatment objective would require a specific optimization of the process. <p><p>In general, this PhD research evidenced the role of the residual adsorption of aged PAC suspensions for the treatment of dissolved compounds. From the results obtained in this project, the potential of HMPs using aged PAC to remove micropollutants was evidenced. Additional research is however required to validate this potential under varied operating conditions. The modeling work improved the understanding of aged PACs. Finally, this research work provides original information on the optimization of HMPs. The optimization of the operating parameters will vary with the water quality targeted and the quality of the influent water. The PAC concentration, PAC age and HRT are inter-related. Therefore, it is recommended to optimize the operation of HMPs at pilot scale. Seasonal variations should be accounted for. An HRT of at least 15 min is required when the biological activity is mandatory to reach the water quality objectives. Lower HRT might be applied if adsorption is favored. Finally, as the HRT has a strong impact on the total cost of the process (capital and operational expenditure), PAC contactors’ hydraulic should be the point of focus of future research.& / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
495

[en] THE IMPORTANCE AND OCCURRENCE OF PHTHALATES IN POTABLE WATERS AND SAMPLES FROM THE GUANABARA BAY ECOSYSTEM / [pt] A IMPORTÂNCIA E OCORRÊNCIA DE FTALATOS EM ÁGUA POTÁVEL E NO ECOSSISTEMA DA BAÍA DE GUANABARA

ISABELLA RODRIGUES LOUREIRO 24 June 2003 (has links)
[pt] Ftalatos são os plastificantes mais utilizados industrialmente, estando disseminados em todos os ecossistemas do mundo. Como são compostos exclusivamente sintéticos, sua presença é indicativa da industrialização de uma região. Sua toxicidade é baixa, porém existem indícios de possíveis efeitos como interferentes endócrinos, especialmente no sistema reprodutor masculino. No Brasil, existem poucos estudos sobre a ocorrência e comportamento dos ftalatos no meio ambiente. Nesta tese foi estudada sua ocorrência em amostras de águas potáveis de diversos bairros das cidades do Rio de Janeiro e Niterói e do ecossistema da Baía de Guanabara (águas, sedimentos e mexilhões), a qual recebe inúmeros aportes industriais. Todas as amostras foram coletadas, extraídas em fase sólida e analisadas por cromatografia em fase gasosa, utilizando detecção por captura de elétrons. As da Baía foram amostradas nas estações seca e chuvosa, em diferentes anos. As extrações de todas as amostras obtiveram excelente repetibilidade e recuperações superiores a 76%. As águas potáveis do Rio de Janeiro e Niterói apresentaram teores de ftalatos em concentrações muito menores do que as informadas para cidades da Europa e Estados Unidos. Tais teores puderam ser correlacionados com as extensões das redes dos sistemas de abastecimento de ambas as cidades. Todas as amostras da Baía mostraram contaminações qualiquantitativas muito inferiores, quando comparadas a outros ambientes costeiros. O estudo do biomonitoramento ativo evidenciou a eficiência e rapidez da depuração dos ftalatos nos mexilhões mais contaminados do ecossistema da Baía de Guanabara. / [en] Phthalates are the most used plasticizers in industrial products, worldwide distributed in environments. Their presence is often used to indicate a region industrialization degree. Although their reported toxicity is low, phthalates are indicated for possible endocrine disrupting effects, specially in male reproductive system. In Brazil, there are few studies about the environmental occurrence and distribution of phthalates. This thesis studied the occurrence of those compounds in potable waters samples from residential areas of Rio de Janeiro and Niterói cities, and in samples from the ecosystem of Guanabara Bay (waters, sediments and mussels), which receives several industrial inputs. All the samples were collected, solid-phase extracted and the phthalate contents analyzed by gas chromatography with electron capture detection. The ones from the Bay were sampled during the dry and rainy seasons, in different years. All the extractions presented excellent repeatability and recoveries above 76%. The potable water samples from both cities presented phthalate values considerably lower than those reported for European and American cities. The results could be correlated with the water net distribution lengths for both cities. All results from the Bay ecosystem showed lower contamination when compared to other coastal environments. The controlled transplant proved quick and efficient phthalate depuration of contaminated organisms from Guanabara Bay.
496

La noción actual de servicio público en el derecho público chileno

Fliman Délano, Gabriel David January 2019 (has links)
Memoria para optar al grado de Licenciado en Ciencias Jurídicas y Sociales / El presente trabajo aborda, desde una perspectiva conceptual y legal, la noción de servicio público y cómo esta se refleja en la organización concreta de ciertos servicios económicos en red: los servicios eléctricos, sanitarios, de gas y telecomunicaciones. Para ello, se analiza la evolución conceptual del servicio público desde una visión de carácter predominantemente orgánico hacia una funcional, que abre espacio para la entrada de los privados a la gestión del servicio, y cómo este tránsito se materializó posteriormente en una atención de las necesidades generales a través de mecanismos de mercado y libre competencia, en sectores anteriormente publificados. Se analizan y comparan las leyes reguladoras de los sectores antes mencionados, los que tienen por finalidad la cobertura de necesidades esenciales para la vida humana y fueron desarrollados en el marco de procesos de urbanización e industrialización durante el siglo XIX, en un diseño jurídico que llamaremos tradicional. A partir de la década de 1970, estos servicios comienzan a experimentar reformas liberalizadoras y procesos privatizadores, que posteriormente debieron complementarse con una nueva regulación que enfrente los desafíos en materia de libre competencia y permitiera a su vez compatibilizar las necesidades de interés general con los intereses empresariales de los nuevos gestores de estas actividades. Trataremos el rol que le corresponderá a los agentes públicos y privados en la gestión de los servicios, la definición de las áreas en que éste se prestará, las prerrogativas públicas que poseerán los concesionarios, los principios que rigen la prestación y explotación del servicio, el régimen tarifario y la forma en que se pondrá fin a los contratos en que se encarga la gestión de los servicios a agentes privados
497

Mikropolutanty ve zdrojích vod a možnosti jejich odstranění / Micropollutants in water resources and ways of their elimination

Lukášová, Daniela January 2018 (has links)
The diploma thesis deals with micro-fuels in drinking water sources and their subsequent removal. In the thesis mainly pesticides and pharmaceuticals are described. The reader is first introduced to the most common pesticides occurring in water and their consumption. Drugs are described in a similar context. In addition, there are practical studies on the occurrence, degradation and removal of micro-pollutants from water. The final thesis is a laboratory experiment dealing with the removal of salicylic acid from water by filtration through the filtration material Bayoxide E33 and activated carbon. The thesis describes the procedure and results of the experiment.
498

Energetická náročnost získávání vody kondenzací vzdušné vlhkosti / The energy intensity of water acquisition by condensation of air humidity

Hamerský, Tomáš January 2019 (has links)
The master's thesis deals with actual possibilities of acquisition water from air humidity in order to obtain fresh water, focusing on energy intensity of vapor-compression refrigeration for it is production. There is a basic determine study for Czech climatic zone in selected localities. For graded cooling capacity dependencies describing the acquisition of water from the air, where is the energy intensity ranges on average between 0,3 ÷ 0,5 kWh/l. For the selected family house are set the individual variants of non-potable rainwater management.
499

Détermination de la concentration de manganèse dans l’eau potable associée à des déficits cognitifs chez l’enfant

Kullar, Savroop S. 06 1900 (has links)
No description available.
500

Eine neue Methode zur Optimierung der Auslegungsparameter von Kraftwerksprozessen ohne und mit Auskopplung von Energie- und Stoffströmen

Werner, Claudia 22 June 2011 (has links)
Der Gegenstand dieser Arbeit ist eine neue Optimierungsmethode zur Minimierung der Produktkosten von Kraftwerksprozessen ohne und mit nachgeschalteten Anwendungen. Diese Methode, die Planern und Projektanten als Werkzeug zur Auslegung von Kraftwerken dienen soll, wird erläutert und exemplarisch zur Optimierung eines ausgewählten Gas- und Dampfturbinenkraftwerkes verwendet. Im Rahmen der Untersuchungen werden dabei zwei Varianten betrachtet: Der Kraftwerksentwurf/-betrieb ohne und mit Auskopplung von Energie- und Stoffströmen. Beim Kraftwerksentwurf/-betrieb mit Auskopplung von Energie- und Stoffströmen wird das Gas- und Dampfturbinenkraftwerk mit einer nachgeschalteten hybriden Meerwasserentsalzungsanlage verknüpft. Zur Identifizierung der jeweils zu optimierenden Komponenten/Parameter werden bei der neuen Methode Elemente der thermo- bzw. exergoökonomischen Analyse und der Sensitivitäts- und Trendlinienanalysen verwendet. Die Optimierung selbst folgt dem Koordinatenverfahren nach Gauß und Seidel. Anhand der Optimierungsergebnisse und der Kriterien ’Auswahl/Beitrag der Komponenten/Parameter’ sowie ’Rechenumfang’ wird die neue Optimierungsmethode mit bekannten thermo- bzw. exergoökonomischen Optimierungsmethoden (Quadranten-/Matrix-Methode, thermo-/exergoökonomische Kennzahlen-Methode) verglichen und bewertet. Zur Ergebnisdiskussion werden Parameterstudien erstellt. Abschließend werden Empfehlungen zur Gestaltung des untersuchten Gas- und Dampfturbinenkraftwerkes gegeben und Ansätze für weiterführende Forschungsarbeiten in der Kraftwerkstechnik abgeleitet.

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