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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.
231

Ferramenta gráfica para o dimensionamento de reservatórios para aproveitamento de águas pluviais: estudo de caso na região norte de Rondônia / Graphical tool for the design of water harvesting tanks: a case study in the north region of Rondônia

Andrade, Vanessa Helena de 16 February 2017 (has links)
Capes / Os sistemas de aproveitamento de águas pluviais têm sido apontados como uma importante fonte para atender às demandas de água. Em geral, o reservatório é o item mais caro do sistema. A depender do modelo o sistema pode ser super ou subdimensionado. Além disso, há a necessidade de associar o cálculo do volume do tanque ao perfil de precipitação da região. Este trabalho tem como objetivo desenvolver uma ferramenta gráfica para auxiliar o dimensionamento de volume de reservatórios para captação de águas pluviais, um estudo de caso na região norte de Rondônia. Propõe-se a elaboração de gráficos de contorno a partir das variáveis: área de captação, volume de reservação e eficiência no atendimento à demanda de água da chuva para uso doméstico e industrial. A eficiência foi obtida por meio do método de simulação de balanço contínuo. Para criar o gráfico de contorno são usados três modelos de ajuste de superfícies, Biharmonic spline interpolant, Locally weighted smoothing quadratic regression e Linear Polynomial disponíveis no software MATLAB. A região de influência das estações pluviométricas selecionadas para simulação de balanço contínuo foi encontrada pelo método Inverso da Distância Ponderada, IDW (Inverse Distance Weighting). Parte da região norte do estado de Rondônia foi definida como área de influência do sistema gráfico. No geral, os métodos de ajuste de superfície apresentaram um bom resultado com R2 maiores que 0,96. O método de interpolação Biharmonic spline interpolant apresentou o melhor resultado demostrando-se adequado na explicação da variação dos dados observados. Isso significa que o gráfico de contorno gerado pode ser usado como ferramenta de auxílio de tomada de decisão no dimensionamento de reservatório mais apropriado. Foram desenvolvidos gráficos de contorno que exibem a eficiência no atendimento às demandas domésticas e industriais por água da chuva, como uma função de uma ampla faixa tanto de área de captação como de volume do tanque pelo método Biharmonic spline interpolant. Os valores de RMSE para validação foram menores que 0,7. As demandas residenciais às quais desenvolveu-se ajuste de superfície e gráficos de contorno variam entre 60 e 600 L d-1; e as demandas industriais de 500 a 50.000 L d-1. / Rainwater harvesting systems have been pointed out as an important source to meet water demands. In general, the reservoir is the most expensive item of the system. Depending on the chosen method, the system can be over- or undersized. In addition, the region rainfall profile must be associated to the design of the tank. Therefore, this study aims to develop a graphical tool to assist rainwater harvesting tanks sizing, a case study in the region of Rondônia. It is proposed to draw a contour plot from the variables: catchment area, reservoir volume and efficiency in meeting domestic and industrial rainwater demands. The efficiency was obtained through the continuous water balance simulation method. Three surface fitting models were used to create the contour plot, Biharmonic spline interpolant, Locally weighted smoothing quadratic regression and Linear Polynomial, available on the MATLAB software. The influence region of the selected rainfall stations used for the continuous balance simulation was found by the Inverse Distance Weighting (IDW) method. Part of the northern region of Rondônia state was defined as graphic system influence area. In general, the surface fitting methods showed a good performance with R2 greater than 0,96. The Biharmonic spline interpolant method presented the best result due to its capability of explaining observed data variation. Hence, the generated contour plot can be used as decision-making aid tool in tank volume selection. Contour plots were developed to show the efficiency in meeting domestic and industrial rainwater demands as a function of a wide range of both catchment area and tank volume through the Biharmonic spline interpolant method. The RMSE values for validation were lower than 0,7. The residential demands to which surface fitting and contour graphics were developed vary between 60 and 600 L d-1; and the industrial demands vary between 500 and 50.000 L d-1.
232

A medição setorizada como instrumento de gestão da demanda de água em sistemas prediais - estudo de caso: Programa de Uso Racional da Água da Universidade de São Paulo. / Submetering as an instrument of water demand management in building systems – case study: Water Conservation Program of the University of São Paulo.

Humberto Oyamada Tamaki 03 April 2003 (has links)
No presente trabalho é estudada a utilização da medição setorizada como instrumento de gestão da demanda de água em sistemas prediais. Para tanto, a caracterização dos medidores e a análise das interações dos elementos de medição com o sistema de suprimento de água fria e de equipamento sanitário são realizados a partir de um enfoque sistêmico e de desempenho. Considerando a coleta de melhores informações, qualitativamente e quantitativamente acerca do consumo, essencial para a gestão da demanda de água, e especialmente em um contexto de ações de conservação, neste trabalho levantou-se os sistemas de telemedição. Apresentou-se uma proposta de planejamento de implantação da medição setorizada e quais elementos que devem ser observados para a gestão da demanda. Para subsidiar as avaliações, realizou-se o estudo de caso da medição setorizada na Universidade de São Paulo, no qual foi possível verificar a importância da sua aplicação e os resultados extremamente positivos que justificaram sua implantação. / In this work it is studied the use of submetering as an instrument of water demand management in building systems. In such way, the characterization of the meters and the analysis of the interactions of its elements with the building hydraulical system are carried on a systemic approach and performance analysis of the proposal. Considering the collection of better information of water consumption essential for the water demand management, especially in a conservation context, it was searched out the systems and the technologies of remote metering. A proposal for the planning of the submetering implantation was showed, as well as the elements that should be considered for the demand management. To make the evaluations, the case study of the submetering program in the University of São Paulo was accomplished, in which it was possible to verify the importance of its application and the extremely positive results that had justified its implantation.
233

Možnosti inovace procesu úpravy vody / Water Treatment Plants Innovation Opportunities

Zelený, Zdeněk January 2014 (has links)
This master´s thesis deals with the possibilities of innovation process water treatment. Specifically, to explore the use of sodium water glass and nanoiron in removing heavy metals from raw water at the drinking water treatment. For the comparison was used traditionally used coagulant, particularly liquid aluminum sulfate. The introductory part deals with the possibility of modifying the surface water during the treatment process such water into potable water. This chapter is a description of the quality of raw water used, then the description of currently used separation processes. Furthermore, they are described and commonly used types of treatment plants. Conclusion The introductory section deals with traditional coagulants and form a suspension. Another part of this master´s thesis has been devoted to the possibilities of innovation in the treatment of raw waters as drinking water, describes the options and features of the use of water glass and nanoiron. The following section describes the experimental part of this thesis. It is followed by the experimental results. The last chapter summarizes the acquired knowledge and commented on the measured values of the experimental part. This work also shows several specific projects using innovative technologies presented.
234

Determining the effectiveness of water treatment process barriers for the removal of viruses in drinking water.

Setlhare, Khomotso Charity January 2018 (has links)
M. Tech (Department of Biotechnology, Faculty of Applied and Computer Sciences) Vaal University of Technology. / The presence of enteric viruses in drinking water poses a health risk to consumers. It is therefore very important for drinking water suppliers to provide water that is pathogen free and fit for human consumption. This can be achieved by an effective water treatment system that ensures the safety of water from the treatment plant until the water reaches the consumer. This study assessed the ability of a conventional water treatment system to remove viruses. The system consisted of three unit processes, namely, clarification, sand filtration and disinfection. These processes were simulated on a bench-scale to determine the effectiveness of each one at removing viruses. Clarification was conducted using a Phipps and Bird jar testing system and three different chemical treatments: (i) Polyelectrolyte (SUDFLOC 3835), (ii) a combination of lime and activated silica and (iii) a combination of lime, activated silica and ferric chloride. Sand filtration was simulated using a Phipps and Bird column filtration system. Disinfection was conducted using free chlorine. The findings from this study showed that the removal or inactivation of viruses increased with an increase in the concentration of chemicals added. For clarification, the combination of lime, activated silica and ferric chloride was the most effective treatment for the removal or inactivation of viruses. Sand filtration was found to be ineffective for the removal of viruses. Disinfection was shown to be the most effective process for the removal or inactivation of viruses. While clarification, sand filtration and disinfection did not remove or inactivate viruses equally, the entire treatment chain is still essential. This is because even if a barrier does not directly remove viruses it ensures that subsequent processes can function effectively. Overall the treatment processes should not be considered as discrete barriers but rather an integrated system that must function throughout to avoid a risk to customers.
235

Wash Water Quality Characterization from Transportation Maintenance Facilities in Ohio During Winter Operations

Sullivan, Sarah E. 17 September 2014 (has links)
No description available.
236

Can Tanker Water Services Contribute to Sustainable Access to Water?: A Systematic Review of Case Studies in Urban Areas

Zozmann, Heinrich, Morgan, Alexander, Klassert, Christian, Klauer, Bernd, Gawel, Erik 16 May 2024 (has links)
Tanker water markets (TWM) supply water services in many urban areas, including those unconnected to public infrastructures. Notwithstanding, they have been associated with outcomes in conflict with sustainability goals of water policy, e.g., through inequitable and unaffordable supply or by contributing to groundwater overexploitation. So far, the literature dedicated to TWM has primarily conducted case studies embedded in diverse local contexts, which impedes the comparison and transfer of insights. In this article, we systematically summarize existing empirical knowledge on TWM and assess to what extent normative claims about the impacts of TWM on sustainability goals are supported by evidence. We use the concept of sustainable access, which combines notions of what constitutes access to water and what characterizes sustainable supply of services. The available evidence suggests that TWM have two key functions in urban water systems: (1) They provide services at otherwise unavailable levels, particularly with respect to the temporal availability and spatial accessibility of the service, and (2) they extend access to areas without or with low-quality network supply, typically low-income communities on the fringe of cities. From the perspective of sustainable access, we find that TWM can provide high service levels and thus fill a specific gap in the landscape of urban water services. Due to comparatively high prices, however, it is unlikely that these services are affordable for all. The combination of heterogeneous access to cheaper (subsidized) piped water and marginal pricing in TWM results in allocation outcomes that are not coherent with existing notions of equitable access to water. However, there is little convincing evidence that TWM necessarily result in unsustainable water use. The literature indicates that urban water governance in the studied areas is frequently characterized by a lack of effective institutions, which impedes the regulation or formalization of TWM.
237

Avaliação da qualidade de águas pluviais armazenadas e estudos de tratabilidade empregando filtro de pressão com diferentes meios filtrantes visando ao aproveitamento para fins não potáveis /

Nakada, Liane Yuri Kondo. January 2012 (has links)
Orientador: Rodrigo Braga Moruzzi / Banca: Alexandre Silveira / Banca: Samuel Conceição de Oliveira / Resumo: O presente trabalho foi desenvolvido em três etapas, cronologicamente: i) estudo da qualidade de águas pluviais coletadas por telhada por telhado cerâmico e armazenadas; ii) modificações em estado experimental em escala real de coleta e tratamento simplificado de águas pluviais, para possibilitar o estudo de três diferentes meios filtrantes; e iii) coletas, estudos de tratabilidade em escala de bancada e estudos do tratamento em escala real. Os resultados indicam que: i) as águas pluviais coletadas após escoamento sobre telhados cerâmicos necessitam de tratamento para assegurar o uso, mesmo que para atividades não potáveis, conforme recomendações da NBR 15527 (ABNT, 2007); cada precipitação possui aspectos qualitativos particulares, significativamente dependentes do período de estiagem antecedente à chuva, de modo que demandam ensaios de tratabilidade para cada evento: ii) a implantação de sistemas de coleta e tratamento/aproveitamento de águas pluviais em novos empreendimentos imobiliários é mais conveniente do que a inclusão desse sistemas como adaptação de sistemas de água já existentes; iii) para as águas pluviais estudadas, em nenhuma configuração de tratamento foi integralmente atendido o padrão de qualidade recomendado pela NBR 15527 (ABNT, 2007), entretanto, a estratégia de tratamento simplificado investigado pode produzir água com a qualidade recomendada / Abstract: The present work was developed in three steps, in the following chronological order: i) study of the quality o stored roof-harvested rainwater; ii) modifications in the full-scale experimental plant for rainwater harvesting and simplified treating, to enable the study of three different media filter, iii) harvest of rainwater, treatability studies in bench scale and study of the full-scale treatment. The results indicate that: i) the ceramic roof-harvested rainwater require treatment to safeguard uses, even for non-drinkable purposes, according to recommendations of the current norm NBR 15527 (ABNT, 2007); each rain event presents specific qualitative aspects, significantly dependent on the dry days before the rain, hence, each harvested rainwater demands treatability studies; ii) the implementation of rainwater harvesting and treatment systems in new buildings is more convenient than the addition of those systems as adaptations of water systems from previolusly existing buildings. iii) for the studied rainwater, nome of the treatment configurations completely met the quality recommended by norm, through, the treatment strategy can produce water which meet the quality recommendations / Mestre
238

The Effect of Salts on the Conformational Stability of Proteins

Beauchamp, David L 13 April 2012 (has links)
It has long been observed that salts affect proteins in a variety of ways, yet comprehensive explanations for different salt effects are still lacking. In the work presented here, the effect of salts on proteins has been investigated through three different effects: the hydrophobic effect; their conformational stability; the hydrogen bonding network of water in a protein’s hydration shell. UV-vis absorbance and fluorescence spectroscopy were used to monitor changes in two model systems, the phenol-acetate contact pair and the model enzyme ribonuclease t1. It was shown that salts affect the hydrophobicity of the contact pair according to their charge density, induced image charges play an important role in the observed salt-induced increase of ribonuclease t1 stability, and that salts affect ribonuclease t1 activity through modulation of the hydrogen bonds of water in the enzyme’s hydration shell. This work contributes a greater understanding of the effect of salts on proteins.
239

The Effect of Salts on the Conformational Stability of Proteins

Beauchamp, David L 13 April 2012 (has links)
It has long been observed that salts affect proteins in a variety of ways, yet comprehensive explanations for different salt effects are still lacking. In the work presented here, the effect of salts on proteins has been investigated through three different effects: the hydrophobic effect; their conformational stability; the hydrogen bonding network of water in a protein’s hydration shell. UV-vis absorbance and fluorescence spectroscopy were used to monitor changes in two model systems, the phenol-acetate contact pair and the model enzyme ribonuclease t1. It was shown that salts affect the hydrophobicity of the contact pair according to their charge density, induced image charges play an important role in the observed salt-induced increase of ribonuclease t1 stability, and that salts affect ribonuclease t1 activity through modulation of the hydrogen bonds of water in the enzyme’s hydration shell. This work contributes a greater understanding of the effect of salts on proteins.
240

Effect of winter storm on water quality and fish toxicity the Duwamish and Nisqually Rivers /

Ubilava, Mariam. January 2007 (has links) (PDF)
Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen viewed (1/17/2008). Includes bibliographical references (leaves 67-68).

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