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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.
731

The development of functionalized electrospun nanofibers for the control of pathogenic microorganisms in water.

Kleyi, Phumelele Eldridge January 2014 (has links)
The thesis presents the development of functionalized electrospun nylon 6 nanofibers for the eradication of pathogenic microorganisms in drinking water. Imidazole derivatives were synthesized as the antimicrobial agents and were characterized by means of NMR spectroscopy, IR spectroscopy, elemental analysis and X-ray crystallography. The first set of compounds (2-substituted N-alkylimidazoles) consisted of imidazole derivatives substituted with different alkyl groups (methyl, ethyl, propyl, butyl, heptyl, octyl, decyl and benzyl) at the 1-position and various functional groups [carboxaldehyde (CHO), alcohol (CH2OH) and carboxylic acid (COOH)] at the 2-position. It was observed that the antimicrobial activity of the compounds increased with increasing alkyl chain length and decreasing pKa of the 2-substituent. It was also observed that the antimicrobial activity was predominantly against a Gram-positive bacterial strains [Staphylococcus aureus (MIC = 5-160 μg/mL) and Bacillus subtilis subsp. spizizenii (MIC = 5-20 μg/mL)], with the latter being the more susceptible. However, the compounds displayed poor antimicrobial activity against Gram-negative bacterial strain, E. coli (MIC = 150- >2500 μg/mL) and did not show any activity against the yeast, C. albicans. The second set of compounds consisted of the silver(I) complexes containing 2-hydroxymethyl-N-alkylimidazoles. The complexes displayed a broad spectrum antimicrobial activity towards the microorganisms that were tested and their activity [E. coli (MIC = 5-40 μg/mL), S. aureus (MIC = 20-80 μg/mL), Bacillus subtilis subsp. spizizenii (MIC = 5-40 μg/mL) and C. albicans (MIC = 40-80 μg/mL)] increased with the alkyl chain length of the 2-hydroxymethyl-N-alkylimidazole. The third set of compounds consisted of the vinylimidazoles containing the vinyl group either at the 1-position or at the 4- or 5- position. The imidazoles with the vinyl group at the 4- or 5-position contained the alkyl group (decyl) at the 1-position. For the fabrication of the antimicrobial nanofibers, the first two sets of imidazole derivatives (2-substituted N-alkylimidazoles and silver(I) complexes) were incorporated into electrospun nylon 6 nanofibers while the third set (2-substituted vinylimidazoles) was immobilized onto electrospun nylon 6 nanofibers employing the graft polymerization method. The antimicrobial nylon nanofibers were characterized by IR spectroscopy and SEM-EDAX (EDS). The electrospun nylon 6 nanofibers incorporated with 2-substituted N-alkylimidazoles displayed moderate to excellent levels of growth reduction against S. aureus (73.2-99.8 percent). For the electrospun nylon 6 nanofibers incorporated with silver(I) complexes, the levels of growth reduction were >99.99 percent, after the antimicrobial activity evaluation using the shake flask method. Furthermore, the grafted electrospun nylon 6 nanofibers showed excellent levels of growth reduction for E. coli (99.94-99.99 percent) and S. aureus (99.93-99.99 percent). The reusability results indicated that the grafted electrospun nylon 6 nanofibers maintained the antibacterial activity until the third cycle of useage. The cytotoxicity studies showed that grafted electrospun nylon 6 nanofibers possess lower cytotoxic effects on Chang liver cells with IC50 values in the range 23.48-26.81 μg/mL. The thesis demonstrated that the development of antimicrobial electrospun nanofibers, with potential for the eradication of pathogenic microoganisms in water, could be accomplished by incorporation as well as immobilization strategies.
732

Selection and prioritization of organic contaminants for monitoring in the drinking water value chain

Ncube, Esper Jacobeth 09 October 2010 (has links)
The occurrence of organic contaminants in the drinking water value chain (from source to tap) is a growing concern for the Drinking Water industry and its consumers given the high risk these contaminants can cause to the general public. These adverse health effects include such as endocrine disruption, toxicity teratogenicity, mutagenicity and carcinogenicity. Some of these organic contaminants are included in national and international drinking water quality guidelines or standards. However, although there are similarities in the list of organic contaminants used by each organization or country, the organic contaminants are never the same given the local conditions. There are also noticeable differences in the concentration limits set as targets or criteria for organic contaminants for public health protection via the use of drinking water. A further question requiring the response from drinking water regulators was whether the standards listed in the international literature would be applicable in other countries like South Africa. Complicating this decision is the fact that the South African National Drinking Water Standard (SANS 241) does not adequately address this component of drinking water quality management. The current standard only provides for dissolved organic carbon (DOC), total trihalomethanes (TTHMs) and phenols. However, the standard contains a statement which specifies that if there is a known organic contaminant, that may pose a health threat, it should be included in the monitoring programme and evaluated against World Health Organization (WHO) guidelines. To safeguard Drinking Water industry customers, it was deemed necessary to investigate this matter and establish a tool to assist with the identification of a list of organic contaminants to be monitored in the drinking water value chain. To achieve this a specific procedure/protocol needed to be developed, hence the aim of this study which was to develop a generic protocol for the selection and prioritization of organic contaminants for monitoring in the drinking water value chain (from source to tap). To achieve this, a critical evaluation and synthesis of the available literature on the approaches for the selection and prioritization of organic variables of priority to the drinking water industry was undertaken as a first step. From the literature review it was evident that there are currently many selection and prioritization approaches which are characterized mainly by the purpose for which the exercise has been conducted for. Approaches that prioritize chemicals according to their importance as environmental contaminants have been developed by government agencies and private industries such as the Health Canada’s Canadian Environmental Protection Agency (CEPA), the United Kingdom’s Institute for Environmental Health (IEH), the European Community’s Oslo and Paris (OSPAR) convention exercise for the protection of the Northeast Atlantic marine environment and the European Union (EU)’s combined monitoring based and modelling based priority setting scheme (EU-COMMPs). A few approaches such as ones published by the United States Environmental Protection Agency (USEPA), address the needs of the Drinking Water industry and there is no generic approach to the selection, prioritization and monitoring of organic contaminants in the drinking water value chain. From the review of selection and prioritization approaches, a generic model was developed. The model consists of three main steps, the compilation of a “pool of organic contaminants, the selection of relevant parameters and criteria to screen organic contaminants and finally the application of criteria to select priority organic contaminants. It was however realized that these steps were not enough if the protocol to be develop will serve its purpose. Selection and prioritization approaches are typically intended to be fairly simple and quick methods for determining the health and environmental hazards posed by the use and release of chemical substances into different environmental systems. This was taken into account during the development of the current protocol. Understanding that a protocol is a predefined written procedural method in the design and implementation of tasks and that these protocols are written whenever it is desirable to standardize a method or procedure to ensure successful reproducibility in a similar set up, a generic protocol was developed based on the model. The protocol developed in this study, operates as a multidisciplinary contaminants management and proactive protocol, thus exchanges toxicological, water quality, agricultural, chemical and public health information. The protocol uses previous or readily available information as a point of departure. It seeks to address the challenge facing the water industry in managing the current and emerging organic contaminants that are relevant to public health protection via the use of drinking water. Once the protocol was developed, it was validated in a prototype drinking water value chain. The exercise comprised of testing each step of the protocol from the selection of the “pool of organic contaminants (Step I) to recommending the final priority list of organic contaminants (Step VII). The implementation was successfully conducted in the Rand Water drinking water value chain. Emphasis of expert judgment was made as each step was validated and the opinion of key stakeholders used to shape the process. During Step III of the protocol, an intensive literature review was conducted to determine organic contaminants that have been identified in ground and surface water systems across the world. As a result of this review, major groups of organic contaminants that have been found to occur in source water resources across the world were identified. The identified groups of organic contaminants include, pesticides, polynuclear aromatic hydrocarbons, per and polyfluoroorganic compounds, polycyclic aromatic hydrocarbons, alkanes and alkenes, C10-C13 Chloroalkanes, pharmaceuticals and personal care products [PPCPs], surfactants, benzotriazoles, cyanotoxins and Carbon-based engineered nanoparticles. The risk profile of the identified organic contaminants was established using the persistence, bio-accumulation and toxicity criteria and the development of water quality monographs as an information dissemination tool. A conceptual framework for the implementation of the protocol by water utilities and relevant institutions has been developed from the experiences learnt during the validation exercise and a priority list of organic contaminants for the monitoring in the drinking water value chain to be used by Rand Water and other water utilities was identified. Some of the organic contaminants on this are currently being analyzed for in The Rand Water’s routine organic monitoring programme. During the validation exercise, the following were noted, <ul> <li>During the identification of the “pool of organic contaminants” from the consulted information sources such as the WHO guidelines for drinking water quality, Health Canada drinking water quality guidelines, the USEPA drinking water quality standards, the New Zealand drinking water quality standards, USEPA IRIS database, the PAN-UK list of registered pesticides for South Africa, the IARC list for recognized carcinogens and the Department of Agriculture pesticides manuals duplications were observed. </li> <li>The time allocated could not allow for the development of water quality monographs for all organic contaminants of concern but for a few selected contaminants whose information was inadequate to allow for decision-making. </li> <li>The determination of concentration levels of organic contaminants in fish, sediment and water samples could have been limited by the failure of current analytical instruments to go down to lower levels at which they occur in the drinking water value chain. <l/i> <li>Only two events could be planned, during the wet season (high flow) and dry season (low flow) based on time and budget constraints. </li> <li>Although various experts were consulted and invited to attend workshops in order to validate the process, the attendance could not be extended to all nine provinces given the time and budget constraints. <br></li></ul> Based on the above, recommendations were made for the dissemination and use of the products emanating from this study. For example, it is recommended that the current protocol be made available to water utilities and the process of revising the current priority list be repeated every 5 years. Further research should be conducted to obtain full coverage of organic contaminants impacting on source water quality in all ground water and surface water systems used as sources for drinking water production. Another major recommendation is the investigation of potential analytical methods that current chromatographic methods with high resolution mass spectrometry to ensure that organic contaminants can be detected at the ng/l to pg/l using a single enrichment method in order to make sure that those organic contaminants that occur at very low concentration in environmental samples can be detected. For example, the realisation that compounds such as synthetic organic polymer residues, emerging disinfectant by-products, detergent metabolites, chlorinated benzenes, alkyl phenol, polyethoxylates, their metabolites and cyanotoxins are continuously discharged into the environment via wastewater and industrial effluent discharges which increases their concentration in aquatic environment and concomitantly their potential to exert adverse health effects in water used as source for the production of drinking water necessitates that each of these groups be added to the current monitoring programme. The current water quality monographs can be used for the benefit of the Drinking Water industry. It is also recommended that a training manual on the production and use of water quality monographs is produced to facilitate their dissemination. CD-ROMs on the water quality monographs can be produced and distributed with the manual. / Thesis (PhD)--University of Pretoria, 2010. / School of Health Systems and Public Health (SHSPH) / PhD / Unrestricted
733

The Vulnerability of the Great Lakes Region to Waterborne Diseases in the Wake of Climate Change : A Literature Review

Tällö, Emma January 2017 (has links)
Clean drinking and recreational water is essential for human survival and contaminated water cause 1.4 million deaths worldwide every year. Both developing and developed countries suffer as a consequence of unsafe water that cause waterborne diseases. The Great Lakes region, located in the United States is no exception. Climate change is predicted to cause an increase in waterborne disease outbreaks, worldwide, in the future. To adapt to this public health threat, vulnerability assessments are necessary. This literature study includes a vulnerability assessment that describes the main factors that affect the spreading of waterborne diseases in the Great Lakes region. Future climate scenarios in the region, and previous outbreaks are also described. The study also includes a statistical analysis where mean temperature and precipitation is plotted against waterborne disease cases. The main conclusion drawn is that the Great Lakes region is at risk of becoming more vulnerable to waterborne diseases in the future, if it does not adapt to climate change.
734

Defluoridation Of Drinking Water Using Activated Alumina

Kanwar, Lalita 08 1900 (has links) (PDF)
Excess fluoride (F-) in drinking water poses a health threat to millions of people around the world. In the present work, activated alumina (AA) has been used as an adsorbent. Data obtained from batch experiments were fitted to the (i) pseudo-first order, (ii) pseudo-second order, and (iii) Langmuir kinetic model. Model (ii) performed better than model (i), and fitted the data well. However, the rate constant for adsorption ka had to be varied as a function of the initial concentration of F- in the liquid phase c0. A more satisfactory approach is provided by Langmuir model, which fitted the data reasonably even though ka was independent of c0. Shreyas (2008) developed a model for the batch adsorption of F- onto porous pellets of AA. Some errors were detected in his computer program were corrected. The parameters of the model were estimated by fitting predictions to data. The parameter values suggest that the adsorption process is likely to be diffusion limited. Column experiments were conducted as follows. The pellets were soaked in deionized water for a time ts before they were loaded into columns. A feed solution having a fluoride concentration cf = 3 mg/L was fed to column and the concentration of F- in the exit stream ce was measured at regular intervals. Breakthrough was deemed to have occurred when ce exceeded the permissible limit (= 1 mg/L). Constant values of the bed height H, and the empty bed contact time tc were used in the experiments. The volume of treated water V, scaled by the volume of the bed Vb, varied strongly with the soaking time ts, with a maximum at ts = 24 h. To understand the possible reasons for this behaviour, XRD, FESEM, and FTIR were used to characterize the surface of AA. Though the concentrations of the surface hydroxyl groups may influence the adsorption of F-, FTIR studies show there is no direct correlation between V/Vb and the concentrations of these groups. The FESEM and XRD studies indicate that fresh AA consists mainly of boehmite, which gradually converted to gibbsite during soaking. For fixed values of H and tc, the dimensionless volume of treated water V/Vb was a maximum at D = 45 mm. This behaviour may be caused by wall effects for small values of D and by occurrence of quasi-static regions near the wall for large values of D. The cost of treated of water was Rs. 0.42/L. It decreased slightly to Rs. 0.37/L after one regeneration cycle, but increased to Rs. 0.41/L after two cycles. The volume of treated water after two regeneration cycles was 595 L/kg. The concentration of Al3+ ions ca in the treated water increased and exceeded the permissible limit of 0.2 mg/L as the number of regeneration cycles increased. The concentration of F- in regeneration effluent cre was in the range 32-70 mg/L. The effluent was subjected to solar distillation, leading to a distillate whose fluoride concentration F- was in the range 9-12 mg/L. The distillate can be discharged into the public sewers, as the permissible limit is 15 mg/L.
735

Définition du potentiel aquifère du sous-sol de la région de Bangui (République Centrafricaine) à l’aide d’outils géochimiques et isotopiques. Aide à la mise en oeuvre d’un plan de diversification des ressources en eau potable à partir des eaux souterraines / Definition of the aquifer potential of the underground of the area of Bangui (Central African Republic) with geochemical and isotopic tools. Contribution to the implementation of a plan to diversify the drinking water supply sources from groundwater.

Djebebe-Ndjiguim, Chantal-Laure 12 December 2014 (has links)
La ville de Bangui, capitale de la République Centrafricaine, est sujette à de grandes difficultés en termes d'alimentation en eau potable. Un moyen de diversifier les ressources est de mettre en exploitation de façon plus importante les eaux souterraines à proximité de la zone urbaine. Deux aquifères existent sur le territoire, un aquifère superficiel dans les niveaux latéritiques et un aquifère en profondeur dans les niveaux carbonatés du Précambrien. L'aquifère superficiel, bien que très exploité, est un réservoir vulnérable et fortement marqué par les sources de pollutions anthropiques. Les caractéristiques isotopiques des eaux indiquent une très forte dépendance aux conditions hydrologiques de recharge et un rôle massif des processus d'évaporation sur la signature des eaux. L'aquifère profond est, quant à lui, dans des conditions semi-confinées et assez bien isolé des influences anthropiques. Les caractéristiques isotopiques des eaux sont en faveur d'une recharge plus homogène, au sein d'un réservoir de taille importante et sur une superficie notable autour de la zone urbaine de Bangui. Les temps de séjour calculés à l'aide du radiocarbone sur les eaux souterraines les plus profondes indiquent des "âges" de l'ordre de plusieurs siècles à environ 3000 ans, traduisant une forte inertie du système aquifère et par là même sont potentiel favorable à une exploitation pérenne et qualitative pour fins de production d'eau potable. / Bangui, capital of the Central African Republic, is subject to great difficulties in terms of drinking water supply. One way to diversify resources is to operate more importantly groundwater near the urban area. Two aquifers exist in the area, a surface water in lateritic levels and a deep aquifer in carbonate levels of the Precambrian. The surface aquifer, although very exploited, is a vulnerable reservoir and is also strongly influenced by anthropogenic sources of pollution. Isotopic characteristics of the water indicate a very strong dependence on hydrological recharge conditions and a massive part of the evaporation of water on the isotopic signature. The deep aquifer is, meanwhile, in a semi-confined situation and relatively well isolated from anthropogenic influences. Isotopic characteristics of the water are in favour of more homogeneous recharge processes, in a large reservoir and over a substantial area around the urban zone of Bangui. The residence times calculated using radiocarbon on the deeper groundwater indicate "ages" of the order of several centuries to about 3000 years, reflecting a strong inertia of the aquifer system and thus favourable exploitation conditions for the development of a sustainable and qualitative drinking water supply from groundwater.
736

Escherichia coli isoladas de agua de consumo : caracterização fenotipica e genotipica das propriedades de virulencia / Escherichia coli isolated from drinking water: fenotypic and genotypic characterization of virulence factors

Ribeiro, Daniela Alves 17 February 2006 (has links)
Orientadores: Tomomasa Yano, Maria Celia S. Lanna / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-07T10:36:24Z (GMT). No. of bitstreams: 1 Ribeiro_DanielaAlves_M.pdf: 9526817 bytes, checksum: 451baed1219c35350316a70f67d5b336 (MD5) Previous issue date: 2006 / Resumo: Estudos de infecções causadas pela ingestão de águas contaminadas, em especial por Escherichia coli, são importantes para definir o papel dessas bactérias em casos de gastroenterites. Devido à ocorrência freqüente da diarréia infantil na cidade de Ouro Preto-MG, análises microbiológicas da sua água de consumo determinaram a presença de E. coli. No presente trabalho, propriedades fenotípicas e genotípicas de virulência foram estudadas em 97 amostras de E. coli isoladas da água de consumo desse município. Os resultados obtidos para padrões de adesão mostraram que 79 (81,4%) amostras aderiram a células HEp-2 em diferentes padrões de adesão, sendo que 49 (62%) amostras aderiram de forma agregativa, 16 (20,3%) apresentaram o padrão difuso, 12 (15,2%) aderiram de forma não característica e 2 (2,5%) apresentaram o perfil de adesão localizada ¿like¿. Por ensaios de hemaglutinação verificou-se que 70 (72%) amostras hemaglutinaram hemácias de cobaia, 64 (65,9%) aglutinaram hemácias eqüinas, 5 (5,2%) foram positivas com hemácias humanas do grupo A e 10 (10,3%) aglutinaram hemácias bovinas. Todas essas amostras evidenciaram um perfil de hemaglutinação manose sensível, o que está associado à presença da fímbria tipo 1. Outro fator de virulência detectado foi a produção de aerobactina em 11 (11,3%) isolados. Em relação à expressão de hemolisinas em meio sólido, 50 amostras de E. coli foram positivas em placas de ágar sangue contendo hemácias de cavalo, 37 lisaram hemácias de carneiro, 28 lisaram eritrócitos de cobaia, nove lisaram eritrócitos humanos e seis foram positivas com hemácias bovinas. Entretanto, os sobrenadantes de cultura de todas essas bactérias não apresentaram atividade hemolítica ¿in vitro¿. Em relação à atividade citotóxica dos sobrenadantes de cultura das amostras, verificou-se que 89 deles provocaram diferentes alterações morfológicas em células Vero, HeLa e CHO. Deste total, 39 apresentaram efeito citotóxico caracterísitico de desarranjo do citoesqueleto celular, foram estáveis ao aquecimento por 100ºC e demonstraram atividade enterotóxica em camundongos recém nascidos. Estudos genotípicos pela PCR, identificaram nove amostras eltIA+, uma amostra stI+, 14 stII+, seis _ hLy+, três sat+, três astA+, duas pic+, 10 kps+, 11 iucD+, 88 fimH+, seis eae+, três papC+ e uma papG1+. Nenhuma amostra foi positiva para os genes stx1, stx2, stx2v, eltIIA, cnfs, cdt, enhly, pet, bfp, inv, K88 e 987p, aggA, aafA e papGII/GIII. Baseado na aderência em células, na produção de toxinas e na presença de genes de virulência, classificou-se 24 amostras como ETEC, 6 como EPEC atípicas , 36 EAEC e 13 como DAEC. Nenhuma amostra foi classificada como EHEC e EIEC. Estes resultados sugerem um possível envolvimento destas amostras de E. coli como um dos agentes enteropatogênicos envolvidos nas infecções entéricas ocorridas na cidade de Ouro Preto / Abstract: Infections studies caused by the ingestion of contaminated water, especially by Escherichia coli, are important to define the pathogenic role of these bacteria in gastroenteritis. Due to frequent infantile diarrhea in the city of Ouro Preto-MG, this city's water microbiologic analysis displayed the presence of E. coli. In the present study, genotypic and phenotypic virulence properties were studied among 97 E. coli strains isolated from the drinking water provided for this city. The obtained results for adhesion patterns showed that 81,4% of the samples adhere to HEp-2 cells in different adhesion patterns, wherein 49 strains adhere in a aggregative pattern, 16 displayed the diffuse pattern, 12 adhered in a non-characteristic pattern and 2 showed the localized adhesion profile ¿like¿. By means of hemagglutination tests we verified that 72 % of the strains hemagglutinated guinea pig erythrocytes, 65,9% agglutinated horse erythrocytes, 5,2% were positives on group A human erythrocytes and 10,3% agglutinated bovine erythrocytes. All these strains made evident a manose sensible hemagglutination profile, which is associated with type 1 fimbriae. Another virulence factor detected was the production of aerobactin in 11,3% of the isolates. Regarding the hemolysin expression in solid medium, 50 E. coli strains were positive in blood agar plates containing horse erythrocytes, 37 lysated sheep erythrocytes, 28 lysated guinea pig erythrocytes, 9 lysated human erythrocytes and 6 were positives on bovine erythrocytes. However, the culture supernatants of all these bacterias didn't displayed any hemolytic activity ¿in vitro¿. This could be associated with a possible b-hemolysin production. In respect of the cytotoxic activity produced by the strains culture supernatants, we verified that 89 of them provoked different morphological alterations in Vero, HeLa and CHO cells. From these, 39 showed a characteristic cytotoxic effect of disarrangement of the cellular cytoskeleton, remained stable when heated by 100ºC and also showed enterotoxic activity in suckling mice. Genotipic studies performed by PCR identified nine eltIA+ strains, one stI+ strain, 14 stII+, six _ hLy+, three sat+, three astA+, two pic+, 10 kps+, 11 iucD+, 88 fimH+, six eae+, three papC+ and one papG1+. None of these results were positive for the following genes stx1, stx2, stx2v, eltIIA, cnfs, cdt, enhly, pet, bfp, inv, K88 e 987p, aggA, aafA e papGII/GIII. Based on the adherence to cells, toxin production and the presence of the virulence genes, 24 strains were classified as ETEC, 6 as atypical EPEC, 36 as EAEC and 13 as DAEC. Anyone strain were classified as EHEC and EIEC. These results suggest a possible involvement of these E.coli strains as one of the enterophatogenic agents related with the enteric infections occurred in the city of Ouro Preto / Mestrado / Microbiologia / Mestre em Genética e Biologia Molecular
737

Determinação de cocaína e metabólitos em amostras de urina de usuários da droga e em amostras ambientais / Determination of cocaine and metabolites in users urine samples and in environmental sample

Campestrini, Iolana, 1985- 27 August 2018 (has links)
Orientador: Wilson de Figueiredo Jardim / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-27T18:04:13Z (GMT). No. of bitstreams: 1 Campestrini_Iolana_D.pdf: 2742870 bytes, checksum: 20a25893a0acbb614cce027eda2bef08 (MD5) Previous issue date: 2015 / Resumo: Este trabalho apresenta a determinação de sete subprodutos da cocaína (COC), incluindo a benzoilecgonina (BE), em amostras de urina de usuários da droga. Com os dados obtidos foi avaliada a incerteza no cálculo da razão entre a BE e o somatório dos demais metabólitos da COC, sendo que a razão média encontrada foi utilizada para inferir sobre o consumo de COC aplicando a epidemiologia do esgoto. Os resultados dessa razão apresentaram grande amplitude de valores e mostrou elevada influência sobre estimativa do consumo. Apresenta, também, a avaliação da eficiência de remoção (ER) para a COC e BE nas estações de tratamento de esgoto (ETE) Anhumas e Capivari e da qualidade de mananciais e de águas de abastecimento do estado de São Paulo. Os melhores índices de remoção foram observados para a ETE Capivari, os quais variaram entre 96 e 99%. Tanto nas amostras de mananciais como nas amostras de água de abastecimento, a BE foi determinada em maiores concentrações do que a COC. Nos rios Piracicaba, Capivari e Anhumas observaram-se os maiores níveis de BE, os quais variaram entre 300 e 1000 ng L-1. Nas amostras de água de abastecimento do rio Capivari e do rio Atibaia foram determinadas as maiores concentrações de BE, chegando a 650 ng L-1. Para a análise dessas amostras foi utilizada a extração em fase sólida (SPE) seguida da cromatografia líquida acoplada à espectrometria de massas sequencial (LC-MS/MS). No geral, o método apresentou exatidão superior a 70%, com coeficiente de variação menor do que 15% no nível de ng L-1 / Abstract: This work describes the determination of seven cocaine (COC) metabolites, including the major one benzoylecgonine (BE), in urine of cocaine users. These determinations allowed the calculation of the ratio between BE concentration and the sum of the other COC metabolites concentration, as well as allowed an assessment of the uncertainty involved in this ratio. The ratios were used to estimate cocaine consumption applying sewage epidemiology yielding high amplitude of values among the ratios calculated. The work also presents COC and BE removal efficiency (RE) in two wastewater treatment plant (WWTP), namely Anhumas and Capiravi, where the best RE were obtained for the Capivari WWTP, which varied between 96% and 99%. Also the assessment of water quality, for both surface and drinking waters of the State of São Paulo, Brazil, was evaluated. The metabolite BE occurred more frequently and at higher concentrations when compared to COC, considering the same samples. For surface water, the highest BE concentrations were found in the Piracicaba, Capivari and Anhumas rivers, and the results varied from 300 to 1000 ng L -1. For drinking waters, the highest BE concentration was found in waters from Capivari and Atibaia rivers, at 650 ng L-1. Solid phase extraction and the liquid chromatography tandem mass spectrometry (LC-MS/MS) were used for the determination of the compounds. In general, the method presented accuracy above 70% and relative standard deviation below 15%, at ng L -1 level / Doutorado / Quimica Analitica / Doutora em Ciências
738

Vyhodnocení účinnosti odstraňování pesticidů na rekonstruované úpravně vody / Evaluation of effectiveness removing pesticides of reconstructed water treatment plant

Kovačíková, Kristýna January 2018 (has links)
Diploma thesis deals with assessing of effectiveness removing pecticides of reconstructed water treatment plant. In the introduction ismade a short research focused on pesticides, their getting into sources of drinking water and possibilities their removing by water supply processes. As part of this work are assessed effectiveness of this processes for removing pesticidal substances on specific water treatment plant and its sources of drinking water. Is made description of technology water treatment plant before and after the reconstruction, measured data of concetration pesticides in the sources and in the output from water treatment plant is processed to the tables and to the graphs. In conclusion are assessed effectiveness of the new technology for removing selected pesticidal substances and their metabolites.
739

Sledování vlivu olověných potrubí na kvalitu pitné vody u spotřebitele / Monitoring the effect of lead pipes on drinking water quality for consumers

Vostrčilová, Markéta January 2018 (has links)
The thesis is divided into several parts. At first, there are written information from the laws and decrees concerning the lead pipeline, drinking water, observance of lead concentrations in drinking water, etc. Then the water connection, the ownership relations to the connection and the materials used for the water connection are defined. The next chapter deals with lead, lead pipeline, lead in drinking water and the legislative requirements for lead content in drinking water. Other part is about the health risks of lead in drinking water. These theoretical parts follow the practical part, which focuses on drinking water quality testing, which was in contact with the lead pipeline. This section describes drinking water sampling principles for determining the concentration of lead, the locations where the samples were taken, the methods used to determine the concentration, the description, the results and the evaluation of the information. The last chapter shows the methods and materials that remove lead from water.
740

Pilotní studie posouzení rizik vybraného vodovodu / Pilot study on the risk assessment of selected water supply

Jedličková, Ivana January 2019 (has links)
This diploma thesis focuses on risk evaluation of water line for public use. The risk analysis is done in compliance with the methodology created by VODÁRENSKÁ AKCIOVÁ SPOLEČNOST, a. s. and by the method WaterRisk, created by Institute of Municipal Water management, Brno University of Technology, Faculty of Civil Engineering. The thesis clarifies the key points of the topic in question. Its readiness for passing in the Czech Republic and its core in relation to legislature. Then the thesis also includes a description of a specific water line. In the following two chapters the risks are studied according to the methodologies chosen.

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