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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.
11

Gestão de recursos hídricos: uma análise a partir dos princípios ambientais

Viegas, Eduardo Coral 14 September 2007 (has links)
O presente trabalho versa sobre a gestão dos recursos hídricos sob a ótica dos princípios ambientais. O acesso à água é um direito humano fundamental. A implementação desse direito encontra-se dificultada em razão do contexto fático global de crise da água. As causas e conseqüências da escassez quali-quantitativa da água estão relacionadas diretamente ao homem, da mesma forma que seu necessário enfrentamento depende de mudanças de percepção e comportamento do próprio ser humano. Preconiza-se o rompimento do paradigma antropocentrista, que deve ser transmutado para uma visão ecocêntrica. A efetivação do direito fundamental de que se trata depende de inúmeras providências, destacando-se a publicização integral da propriedade da água pela Constituição de 1988. A finalidade dessa relevante alteração no regime de dominialidade hídrica foi dar ao Estado o meio para o adequado gerenciamento da água como forma de estabilizar ou reduzir a crise e promover justiça social. Compete ao Estado social a satisfação do bem-estar coletivo, o que é mais factível se tiver sob seu domínio o recurso atualmente escasso e de relevância pública. Os recursos hídricos ingressam no patrimônio estatal na categoria dos bens de uso comum do povo. Apesar disso, sua gestão se dá de forma descentralizada e participativa. Na tarefa de administrar as águas, o jurista utiliza-se dos princípios estruturantes do Direito Ambiental, notabilizando-se os princípios materiais do desenvolvimento sustentável, prevenção, precaução, poluidor-pagador e usuário-pagador. Todos eles estão previstos pela Constituição Federal. O desenvolvimento sustentável é um sobreprincípio, sendo mais do que um princípio. O critério de ponderação que é utilizado para solver o conflito entre princípios, no caso do ecodesenvolvimento aplica-se apenas entre seus elementos internos, não entre o desenvolvimento sustentável e outros princípios. Este princípio-reitor é muito útil na apreciação do modelo de produção de energia hidrelétrica, que causa degradações ambientais significativas, e sempre tem repercussão, também, nos planos econômico e social. Os princípios da prevenção e da precaução servem à proteção dos mananciais superficiais e subterrâneos. A precaução, porém, auxilia de forma mais apropriada na defesa das águas subterrâneas, uma vez que o estado da técnica não permite mensurar qual o impacto ambiental do consumo excessivo de água de poços, que consiste em uma realidade contemporânea crescente. Os princípios do poluidor-pagador e do usuário-pagador fundamentam teoricamente o instrumento da cobrança pela utilização dos recursos hídricos, que o legislador resolveu adotar como forma de incentivar a racionalização do uso da água. A pesquisa é do tipo bibliográfica. O método-base adotado é o analítico. Diversas formas de análise foram empregadas, registrando-se a estruturalista, a histórica e a descritiva. Como a adoção de um método-base não afasta a aplicação dos demais, pois cada trabalho científico acaba sendo construído de modo singular, utilizaram-se também, ao longo da dissertação, os métodos dialético, hermenêutico e sistêmico. / The present work concerns the natural water resource management under the evironmental principles. Access to water is a basic human right. The implementation of this right is made all the more difficult on account of the global water crisis. The causes and consequences of these quality and quantity shortages of fresh water are directly related to man, likewise, in adequately facing this problem, a change in perception and behavior must be undertaken by humankind. A move away from the pattern of anthropocentrism to a more ecocentric view is needed. Carrying out these basic laws depends on innumerable steps, clarified in the integral publication of water properties in the constitution of 1988. The objective of this relevant alteration in water property was to give the state the means for the adequate management of water as a form of stabilizing or reducing the crisis and promoting social justice. It is the responsibility of the state to see to collective well being, which is made easier when the resource, which is presently scarce, is held under it s domain of public relevance. Natural water resources are held under the category of common use resources within the patrimony of the state. Despite this, it is managed in a decentralized and collaborative fashion. In the task of managing these water resources, the jurist uses the structured principles of Environmental Law, observing the main principles of sustainable development, prevention, precaution, paying pollutant and paying user. All of which have been foreseen by the Federal constitution. Sustainable development is more than a principle. The basis of consideration used to solve the conflict between the principles, in the case of eco-development is only applied within its internal elements, not within sustainable development and other principles. This fundamental principle is very useful in the appreciation of the model of production of hydroelectric energy, which causes significant environmental degradation and always has repercussions within economic and social plans. Precaution, however, acts as a more appropriate method of protecting subterranean waters, whereby the technical state no longer permits the measuring of the environmental impact of excessive consumption of well water, which includes a growing contemporary reality. The principles of the paying pollutant and the paying user theoretically substantiate the instrument of collective use of natural water resources, which the legislator resolved to adopt in order to stimulate rationing in the use of water. The research is in a bibliographical format. The method-base is analytical. Various forms of analysis were used, including structuralistic, historic and descriptive types. As the adoption of a certain method-base does not dismiss the need of others, so each scientific project is formed in a singular fashion, including, within the dissertation, dialectic, hermeneutic and systemic methods.
12

Právní úprava územní ochrany vod z hlediska množství / Legal regulation of territorial protection of water in terms of quantity

Dvořák, Petr January 2017 (has links)
The thesis deals with the legal regulation of territorial protection of water in terms of quantity, which is contained in the Water Act. I am only focusing on the Protected Areas of Natural Water Accumulation and Surface Water Accumulation Protected Areas as they have significant potential to reduce the effects of drought. Both areas are viewed through common problem, which is the point of view of the amount of water. The legal regulation of the territorial protection of waters in terms of quantity is discussed in connection with other laws. The aim of this work is to answer the question whether the legal regulation of territorial protection of waters in terms of quantity in the Water Act is sufficient to enable the Czech Republic to adapt adequately to the ongoing climate change, that ultimately causes the loss of water. The first part of the thesis deals with sources of legal regulation of territorial protection of water in terms of quantity, further includes the systematics of the Water Act and the Strategy on Adaptation to Climate Change in the Czech Republic (Adaptation Strategy of the Czech Republic). The second part analyses the Protected Areas of Natural Water Accumulation, prohibitions therein contained prohibitions, exemption from prohibitions and damage compensation. The third part deals...
13

Détection de matériaux énergétiques dans les eaux naturelles souterraines par spectroscopie de résonance des plasmons de surface portable

Granger, Genevieve 03 1900 (has links)
Au cours des dernières années, les matériaux énergétiques, tels que le 2,4,6-trinitrotoluène (TNT) et le 1,3,5-trinitro perhydro-1,3,5-triazine (RDX), ont été utilisés lors des activités d’entrainement militaire, ayant un impact potentiel sur l’environnement, les bases militaires, la population environnante, la faune et la flore. Sur les champs de tir, les sols à proximité des cibles et autour des positions de tir nécessitent une surveillance particulière, puisqu’il est possible de trouver une importante quantité de résidus d’explosif qui peuvent être transportés vers les eaux de surface et des eaux souterraines avec les précipitations. Toutefois, la procédure actuelle pour détecter des matériaux énergétiques dans l'eau naturelle est complexe, longue, nécessite un personnel hautement spécialisé et augmente le risque de contamination croisée. Par conséquent, il est difficile d'assurer un contrôle rapide et continu des contaminants. En fait, l'objectif des travaux présentés dans ce mémoire est de développer une technique pour identifier et quantifier les explosifs et leurs produits de dégradation dans les eaux naturelles. En outre, ce test doit être in situ, en continu, peu coûteux et rapide. La résonance des plasmons de surface (SPR) a été donc utilisée pour quantifier les matériaux énergétiques. Une matrice de bis-aniline réticulée avec des nanoparticules d’or (AuNPs) est utilisée en tant que polymère à empreinte moléculaire (MIP) sur le film d'or pour capturer sélectivement le composé d’intérêt. L'association de la molécule d’intérêt, tel que le TNT ou RDX, au MIP par interactions π-donneur-accepteur permet la détection d'explosifs suite aux changements d’indice de réfraction sur la sonde. Le couplage entre les plasmons des AuNPs et de la couche d'or peut également augmenter les signaux SPR. Le test optimisé a ensuite été utilisé sur une base militaire canadienne. L'utilisation de cet essai à base de MIP fournit un outil pour l'extraction et la pré-concentration de TNT ou RDX à la surface d’une sonde SPR et permet leur détection en continu de faibles concentrations dans les eaux naturelles. / Over the last few years, energetic materials such as 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) have been used and show a probable environmental impact on military bases, the surrounding population, fauna and flora, caused by military training involving munitions. On shooting ranges, soils near the firing positions and around targets require special monitoring, since the quantities of explosives residues found can be significant, and these compounds can be transported to surface water and groundwater by precipitation. However, the current procedure to detect energetic materials in natural water is complex, long and poorly adapted to. These operations require highly specialized personnel and increase the risk of cross contamination. Therefore, it is difficult to ensure a fast and continuous monitoring of the contaminants. Here, the objective is to develop a technique for identifying and quantifying explosives and their degradation products in natural water. Also, this test has to be in-situ, inexpensive and fast. Surface plasmon resonance (SPR) has been proposed to probe energetic materials. A bis-aniline-cross-linked gold nanoparticles (AuNPs) matrix is used as a molecular imprinted polymer (MIP) on gold film to selectively capture the target compound. The association of the target such as TNT or RDX to the MIP with π-donor-acceptor interactions have allow the detection of explosives by following SPR refractive changes. Plasmon coupling effects between the AuNPs and the gold film could also increase the SPR signals. The optimal sensor was then used on site to detect RDX in underground water of a Canadian military base. The utilisation of MIP based assay will provide a tool for the extraction and pre-concentration of TNT or RDX on the detector’s surface and will allow the detection of lower concentrations in natural water.
14

Posouzení vhodnosti termální vody pro relaxačně terapeutické využití / Assessment of the suitability of thermal water for the relaxational- therapeutic application

Lysý, Jakub January 2010 (has links)
My thesis is based on an assessment of the suitability of thermal spring in the Southern Moravia for a relaxing, therapeutic purposes. By capillary electrophoresis are measured concentration of natural substancies, which are used in thermal waters and are searched for therapeutic effects.
15

Fotolitička i fotokatalitička razgradnja odabranih herbicida u vodenoj sredini / Photolytic and photocatalytic degradation of selected herbicides in aqueous media

Despotović Vesna 10 July 2014 (has links)
<p>Ispitana je kinetika i mehanizam fotokatalitičke&nbsp;razgradnje herbicida kvinmeraka i klomazona u prisustvu&nbsp;UV/TiO<sub>2</sub>&nbsp; Degussa P25, odnosno piklorama i&nbsp; klopiralida&nbsp;<br />primenom UV/TiO<sub>2</sub>&nbsp; Wackherr pri različitim&nbsp;eksperimentalnim uslovima. Praćena je i kinetika&nbsp;razgradnje odabranih herbicida direktnom fotolizom uz&nbsp;primenu sunčevog, UV i vidljivog zračenja, kao i u&nbsp;odsustvu svetlosti. Pored toga, upoređena je efikasnost&nbsp;<br />UV/TiO<sub>2</sub>&nbsp; Degussa P25, odnosno UV/TiO<sub>2</sub>&nbsp; Wackherr sa&nbsp;vidljivim zračenjem, kao i direktnom fotolizom u&nbsp;prisustvu pomenutih izvora svetlosti.&nbsp; U cilju procene&nbsp;<br />citotoksičnosti klomazona i klopiralida, kao i sme&scaron;e&nbsp;klomazona i klopiralida i njihovih intermedijera nastalih&nbsp;tokom fotokatalitičke razgradnje ispitan je&nbsp; in vitro&nbsp; rast&nbsp;<br />ćelijskih linija&nbsp; MRC-5 i H-4-II-E.&nbsp; Nakon ispitivanja&nbsp;fotokatalitičke razgradnje odabranih herbicida u dvaput&nbsp;destilovanoj vodi, praćena je njihova razgradnja i u&nbsp;prirodnim vodama. Takođe, ispitan je uticaj dodatka&nbsp;hidrogenkarbonata i huminske kiseline na efikasnost&nbsp;razgradnje odabranih herbicida. Fotokatalitička razgradnja&nbsp;klomazona, piklorama i mekopropa je ispitivana i u&nbsp;prisustvu UV/TiO<sub>2</sub>&nbsp; nanocevi. Aktivnost katalizatora TiO<sub>2&nbsp;</sub>Wackherr&nbsp; i TiO<sub>2</sub>&nbsp; nanocevi je upoređena sa TiO<sub>2</sub>&nbsp; Degussa&nbsp;P25.</p> / <p>The kinetics and mechanism of photocatalytic degradation&nbsp;of the herbicides quinmerac and clomazone in the&nbsp;presence of UV/TiO<sub>2</sub>&nbsp; Degussa P25, and of picloram and&nbsp;clopyralid using UV/TiO<sub>2</sub>&nbsp; Wackherr under different&nbsp;experimental conditions were studied. The kinetics of&nbsp;degradation of selected herbicides by direct photolysis&nbsp;using sunlight, UV and visible radiation, and in the&nbsp;absence of light were followed. In addition, the&nbsp;efficiencies of UV/TiO<sub>2</sub>&nbsp; Degussa P25 and UV/TiO<sub>2&nbsp;</sub>Wackherr &nbsp;were compared with visible radiation and direct&nbsp;photolysis in the presence of the above mentioned light&nbsp;sources. In order to evaluate the cytotoxicity of clomazone&nbsp;<br />and clopyralid alone and in their mixture with&nbsp;intermediates formed during the photocatalytic&nbsp;degradation, in vitro growth of cell lines, MRC-5 and H-4-II-E was followed. After examining&nbsp; the photocatalytic&nbsp;degradation of selected herbicides in double distilled&nbsp;water, their decomposition in natural waters was also&nbsp;followed. Also, the influence of hydrogencarbonate and&nbsp;humic acid addition on the efficiency of degradation of&nbsp;selected herbicides was studied. Photocatalytic&nbsp;degradations of clomazone, picloram and mecoprop were&nbsp;investigated in the presence of UV/TiO<sub>2&nbsp;</sub>nanotubes. Activities of the catalysts TiO<sub>2</sub>&nbsp; Wackherr and TiO<sub>2&nbsp;</sub>nanotubes were compared to TiO<sub>2</sub> Degussa P25.</p>
16

Analyse des nanoparticules de dioxyde de cérium à l’aide de l’ICP-MS en mode particule unique

Jreije, Ibrahim 12 1900 (has links)
Due to their unique properties, engineered nanomaterials are now widely used in numerous commercial products. Cerium oxide (CeO2) nanoparticles (NPs) are among the most commonly used engineered NPs, with applications in surface coatings, catalysis, the manufacturing of semiconductors, biomedicine and agriculture. With the significant increase in the production and use of CeO2 NPs, concern is increasing over their release into the environment and their subsequent fate and toxicity. In order to evaluate their environmental risk, it is necessary to detect, quantify and characterize the NPs in all environmental compartments. Unfortunately, analyses of NPs in natural systems are challenging due to their small sizes, their low concentrations (∼ ng L-1) and the complexity of environmental matrices, which also contain natural colloids. Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) is a specific and sensitive technique that enables the detection of very low concentrations (∼ ng L-1) of NPs and it can provide information on their number concentrations, sizes, and size distributions. This technique is often limited by high size detection limits (SDL). However, it is especially important to obtain rigorous size, concentration, and fate data for the smallest NPs, since they are expected to have the greatest environmental risk. To that end, the specific objective of this thesis was to develop an improved method for the detection, quantification, and characterization of CeO2 NPs in complex natural waters using SP-ICP-MS. The project was then divided into several objectives: (1) decrease the SDL for CeO2 NPs; (2) optimize the preparation method for natural water samples; (3) apply the preparation and the analysis methods to detect, quantify, and characterize CeO2 NPs in several natural water samples and commercial products, such as a paint and a stain; (4) identify the origin (natural or engineered) of the detected CeO2 NPs; (5) quantify and characterize the release of CeO2 NPs from paint and stain under natural weathering scenarios; and (6) evaluate the effect of different physicochemical conditions (pH, ionic strength, and NOM) on the fate of CeO2 NPs after their release. A high sensitivity sector field ICP-MS (SF-ICP-MS) with microsecond dwell times (50 μs) was used to lower the SDL of CeO2 NPs to below 4.0 nm. While filtration is often used as a preparation method for SP-ICP-MS, its effect on the concentrations and sizes of NPs is unknown. For this purpose, the interactions between six different membrane filters and CeO2 NPs in aqueous samples were examined. The highest recoveries were observed for polypropylene membranes, where 60 % of the pre-filtration NPs were found in a rainwater and 75% were found in a river water. Recoveries could be increased to over 80% by pre-conditioning the filtration membranes with a multi-element solution. Similar recoveries were obtained when samples were centrifuged at low centrifugal forces (≤1000xg). SF-ICP-MS was then used to detect CeO2 NPs in Montreal rainwater, St. Lawrence River water, a paint, and a stain. A significant decrease in the concentrations of CeO2 NPs, initially contained in paint and stain, was measured over time under different conditions, which was attributed to agglomeration and/or dissolution. Finally, when painted and stained panels were placed outside, the released Ce in the precipitation was mainly in the dissolved form with no significant release of CeO2 NPs. / En raison de leurs propriétés uniques, les nanomatériaux manufacturés sont maintenant largement utilisés dans de nombreux produits commerciaux. Les nanoparticules (NPs) de dioxyde de cérium (CeO2) sont parmi les NPs manufacturées les plus couramment utilisées, avec des applications dans les revêtements de surface, la catalyse, la fabrication de semi-conducteurs, la biomédecine et l’agriculture. Avec l’augmentation significative de la production et l’utilisation des NPs de CeO2, l’inquiétude grandit quant à leur rejet dans l’environnement et à leur devenir et toxicité subséquente. Afin d’évaluer leur risque environnemental, il est nécessaire de détecter, quantifier et caractériser les NPs dans tous les compartiments environnementaux. Malheureusement, les analyses des NPs dans les systèmes naturels sont difficiles en raison de leurs petites tailles, de leurs faibles concentrations (∼ ng L-1) et de la complexité des matrices environnementales, qui contiennent également des colloïdes naturels. La spectrométrie de masse à plasma à couplage inductif en mode particule unique (SP-ICP-MS) est une technique spécifique et sensible qui permet la détection de très faibles concentrations (∼ ng L-1) de NPs en fournissant des informations sur leurs concentrations en nombre, leurs tailles et leurs distributions de taille. Cette technique est souvent limitée par des limites de détection de taille (SDL) élevées. Cependant, il est particulièrement important d’obtenir des données précises sur la taille, la concentration et le devenir des plus petites NPs, qui présentent un plus grand risque environnemental. À cette fin, l’objectif spécifique de cette thèse était de développer une méthode améliorée pour la détection, la quantification et la caractérisation des NPs de CeO2 dans les eaux naturelles complexes à l’aide de SP-ICP-MS. Le projet a ensuite été divisé en plusieurs parties : (1) diminuer la SDL pour les NPs de CeO2; (2) optimiser la méthode de préparation des échantillons d’eau naturelle; (3) appliquer les méthodes de préparation et d’analyse pour détecter, quantifier et caractériser les NPs de CeO2 dans plusieurs échantillons d’eau naturelle et produits commerciaux, telles qu’une peinture et une teinture; (4) identifier l’origine (naturelle ou manufacturée) des NPs de CeO2 détectées; (5) quantifier et caractériser le relargage des NPs de CeO2 de la peinture et de la teinture sous différents scénarios météorologiques; et (6) Évaluer l’effet des différentes conditions physicochimiques (pH, force ionique, et la présence de la matière organique naturelle) sur le devenir des NPs de CeO2 après le relargage. Un ICP-MS à secteur magnétique (SF-ICP-MS) à haute sensibilité avec des temps d’acquisition (i.e. ‘dwell times’) à l’échelle de microsecondes (50 μs) a été utilisé pour diminuer la SDL des NPs de CeO2 à moins de 4.0 nm. Alors que la filtration est souvent utilisée comme méthode de préparation pour le SP-ICP-MS, son effet sur les concentrations et les tailles des NPs est inconnu. Pour cela, les interactions entre six filtres avec des membranes différentes et les NPs de CeO2 dans des échantillons aqueux ont été examinées. Les recouvrements les plus élevés ont été observés pour la membrane de polypropylène, où 60% des NPs de pré-filtration ont été trouvées dans l’eau de pluie et 75% dans les eaux de rivière. Les recouvrements pourraient être augmentés à plus de 80% en préconditionnant les membranes des filtres avec une solution multi-éléments. Des recouvrements similaires ont été obtenus lorsque les échantillons ont été centrifugés à une faible vitesse de rotation (≤1000xg). Le SF-ICP-MS a ensuite été utilisé pour détecter des NPs de CeO2 dans une eau de pluie de Montréal, une eau du fleuve St. Laurent, une peinture et une teinture. En se basant sur le rapport de cérium/lanthane (Ce/La), les NPs de CeO2 détectées dans la pluie sont majoritairement d’origine naturelle alors que celles dans la peinture et la teinture sont manufacturées. Une diminution significative des concentrations des NPs de CeO2, originairement contenues dans la peinture et la teinture, a été mesurée avec le temps, sous l’effet de différentes conditions, ce qui a été attribué à l’agglomération et/ou la dissolution. Finalement, lorsque des panneaux peints et teints ont été placés à l’extérieur, le Ce relargué était principalement sous la forme dissoute, sans relargage significatif des NPs de CeO2.
17

Právní režim chráněných území a ochranných pásem v ochraně vod / Legal regime of protected areas and protective zones by the water protection

Zíbrt, Daniel January 2016 (has links)
84 ABSTRACT This thesis is concerned on the topic "Legal regime of protected areas and protective zones by the water protection." Water like environmental compartment has a key role to the existence of life on Earth. That is the reason for its protection. For achieving this protection could not be protected only this environmental compartment, but it is necessary to focus on other ones, which are related to this protection. The main aim of this thesis is to analyse the situation and the ways of ensuring the territorial water protection, to point out the basic types of them and their similar and different characteristics and provide a comprehensive explication of territorial water protection. For these reasons, the thesis is divided into two parts. The first is dealing with systematization of water protection and water protection relationship as a whole and territorial water protection as one of its important elements. This part is necessary for the orientation and the issue of inclusion territorial water protection to the entire system of water protection. The second part of this thesis at first reflects on the ways of promulgation of types of the territorial water protection and then is directly focused on them. The first type of territorial water protection represents the protected area of natural water...

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