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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.
181

Maintaining Private Water Well Systems

Farrell-Poe, Kitt, Pater, Susan 02 1900 (has links)
5 pp. / 1. Drinking Water Wells; 2. Private Water Well Components; 3. Do Deeper Wells Mean Better Water; 4. Maintaining Your Private Well Water System; 5. Private Well Protection; 6. Well Water Testing and Understanding the Results; 7. Obtaining a Water Sample for Bacterial Analysis; 8. Microorganisms in Private Water Wells; 9. Lead in Private Water Wells; 10. Nitrate in Private Water Wells; 11.Arsenic in Private Water Wells; 12. Matching Drinking Water Quality Problems to Treatment Methods; 13. Commonly Available Home Water Treatment Systems; 14. Hard Water: To Soften or Not to Soften; 15. Shock Chlorination of Private Water Wells / This fact sheet is one in a series of fifteen for private water well owners. The one- to four-page fact sheets will be assembled into a two-pocket folder entitled Private Well Owners Guide. The titles will also be a part of the Changing Rural Landscapes project whose goal is to educate exurban, small acreage residents. The authors have made every effort to align the fact sheets with the proposed Arizona Cooperative Extension booklet An Arizona Well Owners Guide to Water Sources, Quality, Sources, Testing, Treatment, and Well Maintenance by Artiola and Uhlman. The private well owner project was funded by both the University of Arizonas Water Sustainability Program-Technology and Research Initiative Fund and the USDA-CSREES Region 9 Water Quality Program.
182

Private Well Protection

Farrell-Poe, Kitt, Pater, Susan 02 1900 (has links)
3 pp. / 1. Drinking Water Wells; 2. Private Water Well Components; 3. Do Deeper Wells Mean Better Water; 4. Maintaining Your Private Well Water System; 5. Private Well Protection; 6. Well Water Testing and Understanding the Results; 7. Obtaining a Water Sample for Bacterial Analysis; 8. Microorganisms in Private Water Wells; 9. Lead in Private Water Wells; 10. Nitrate in Private Water Wells; 11.Arsenic in Private Water Wells; 12. Matching Drinking Water Quality Problems to Treatment Methods; 13. Commonly Available Home Water Treatment Systems; 14. Hard Water: To Soften or Not to Soften; 15. Shock Chlorination of Private Water Wells / This fact sheet is one in a series of fifteen for private water well owners. The one- to four-page fact sheets will be assembled into a two-pocket folder entitled Private Well Owners Guide. The titles will also be a part of the Changing Rural Landscapes project whose goal is to educate exurban, small acreage residents. The authors have made every effort to align the fact sheets with the proposed Arizona Cooperative Extension booklet An Arizona Well Owners Guide to Water Sources, Quality, Sources, Testing, Treatment, and Well Maintenance by Artiola and Uhlman. The private well owner project was funded by both the University of Arizonas Water Sustainability Program-Technology and Research Initiative Fund and the USDA-CSREES Region 9 Water Quality Program.
183

Spatially Derived Risk Factors for Cutaneous Melanoma

Langston, Marvin Epolian, Langston, Marvin Epolian January 2016 (has links)
Intermittent sun exposure and sun sensitivity factors are the most well described risk factors for the development of cutaneous melanoma (CM). Other potential environmental risks for CM, such as arsenic, are rarely examined. Total sun exposure has not been a consistent risk factor for CM, but recall bias in self-reporting sun exposure throughout life may limit the ability to detect a true association. Objective measures of sun exposure including remotely sensed ambient ultra-violet radiation (UVR) may allow for better capture of total sun exposure. In three chapters, spatially derived factors (ambient UVR, environmental soil arsenic, drinking water arsenic) were observed to determine their relevance in exposure assessment and subsequent risk for CM.UVR trends were investigated using available satellite data (1978-2014) to generate inferences for UVB changes over time in the United States. We found that UVB changed across the study area, but these changes lack biological relevance based on the magnitude of changes observed. Thus, a more objective measure of lifetime ambient sun exposure may be estimated using 30-year average UVR by month in future studies. The spatial correlation between environmental soil arsenic and drinking water across the state of Iowa was investigated. Arsenic concentrations in soil were not significantly spatially correlated with either municipal public water source or non-municipal water source arsenic concentrations. Based on these findings, soil arsenic may not serve as a valid surrogate marker for arsenic in drinking water.In Chapter 5, we assessed the relationship of spatially derived estimates of lifetime ambient UVR, environmental arsenic exposure from soil and drinking water, and CM in a population-based case-control study. Our findings suggest that total sun exposure is positively associated with CM, while arsenic concentration in environmental soil and drinking water were not associated. Sun exposure measured through ambient UVR exposure may allow for better understanding of the association between cumulative or total sun exposure and CM. Additionally, more studies need to be completed to estimate the potential risks for CM in regions where high arsenic concentrations may not be endemic.
184

Mässingslegeringar med låg blyhalt för svarvade komponenter ämnade för dricksvatten

Gyhlesten Back, Jessica January 2011 (has links)
This thesis is about brass alloys with low lead levels for manufacturing of turned components destined for human consumption. Is it technically possible, economically viable and environmentally necessary to produce lead-free brass alloys? Turning tests and leaching tests has been carried out in low-lead brass. The result of the tests carried out show that it is technically possible to produce faucets in low-leaded brass, but since these alloys are harder and less ductile, it takes more power and more cooling when it is processed. There should be more reality-based tests in regular machines that belong in the line of manufacturing. Tests is needed to find out which tool materials, cutting angles, cooling, etc. which are needed to manufacture products with the right surface, dimensions, durability, etc. One thing that no one knows today is the lifetime of a faucet made of low-lead brass. If these faucet’s do not have a higher life than that made in CW 602 N, it is a major strain on nature to produce these in low-lead brass, then to maintain production of the faucets as it is today. No information has come from the Boverket of tougher requirements for lead content in brass. This makes it difficult to know how much effort that is needed to replace lead. A legal requirement or to lose market areas is otherwise a good motivation to move forward. / <p>http://www.du.se/md:Materialdesign är en civilingenjörsutbildning som ges i samarbete mellan Högskolan Dalarna (HDa) i Borlänge och Kungliga Tekniska Högskolan (KTH) i Stockholm. Det är KTH som utfärdar examensbeviset, även för dig som studerar i Borlänge.</p>
185

Die evaluasie van Suid-Afrikaanse filtermedia vir diepbedfiltrasie

22 September 2015 (has links)
M.Ing. / A number of distinctly different local and international media specifications are currently being used in South Africa. Along with some opposing requirements, these specifications all specify different testing procedures to be used in the evaluation of filter media. Furthermore the already confusing situation is being complicated by a lack of knowledge as to the general properties of South African filter media ...
186

Immunoassay test strip for Microcystin-LR detection

Unknown Date (has links)
Microcystin-LR (MCLR) is hepatotoxic to animals and humans with disruption of liver structure causing cytoskeletal damage, necrosis and pooling of blood in the liver, leading to large increase in liver weight. It is also a strong liver tumor promoter and protein phosphatase inhibitor. Microcysin-LR binds protein phosphatases 1 and 2A, and influences regulation of cellular protein phosphorylation. In the present study, a colloidal gold based immunoassay test strip was developed for Microcystin-LR detection. The detection limit was found to be 1 ng/mL. 5 nm colloidal gold test strips exhibits more efficient for detection, compared with 20 nm colloidal gold test strips. The interaction between Microcystin-LR antibody (immunoglobulin G) and colloidal gold nanoparticles was investigated by various analytical methods, including Ultraviolet/Visible (UV/VIS), Fourier Transform Infrared (FTIR) and Fluorescence spectroscopy as well as transmission electron microscopy (TEM). / by Jiesi Xu. / Thesis (M.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
187

Caracterização e otimização analítica na determinação de trialometanos em águas potáveis por purga e armadilha acoplada à cromatografia a gás / Analytical characterization and optimization in the determination of trihalomethanes on drinking water by purge and trap coupled to a gas chromatography

Costa Junior, Nelson Vicente da 30 March 2010 (has links)
Neste trabalho desenvolveu-se uma metodologia analítica para determinação do teor de trialometanos THMs em amostras de águas potáveis, utilizando a técnica de purga e armadilha acoplada à cromatografia a gás (GCPT). Os THMs são subprodutos da cloração da água que devem possuir um limite máximo de 100 &mu;g.L-1 segundo a legislação brasileira, estes compostos são suspeitos carcinogênicos humanos com base em estudos em animais de laboratório. A técnica de purga e armadilha extrai eficientemente estes compostos da água e a separação no cromatógrafo a gás ocorre utilizando coluna de leve polaridade e detector por captura de elétrons. Este detector é seletivo e o mais sensível para estes compostos halogenados. A metodologia desenvolvida foi validada nos itens de: linearidade, seletividade, exatidão, precisão, limite de quantificação, limite de detecção e robustez. O limite de detecção para os THMs foi menor do que 0,5 &mu;g.L-1. A exatidão e precisão foram adequadas para ensaios de compostos traços. As amostras de água potável foram coletadas na cidade de Suzano-SP, que pertence à região do Alto do Tietê, nesta região nas margens do rio a vegetação é predominante. Entre todos os THMs, o composto encontrado na água potável em maiores concentrações foi o clorofórmio onde os resultados quantitativos, utilizando esta metodologia apresentaram teores entre 15,9 à 111,0 &mu;g.L-1 em águas potáveis. / This work shows an analytical methodology developed and optimized to determine trihalomethanes level THMs, in drinking water samples, using purge and trap coupled to gas chromatography (GC-PT). THMs are byproducts water chlorination, these compounds must have a maximum of 100 &mu;g.L-1 under Brazilian law, due these compounds be suspected human carcinogens base on studies in laboratory animals. The technique of purge and trap efficiently extracts these compounds from water, and the gas chromatograph separates the THMs. The GC uses a light polarity column and electron capture detector. This detector is selective and more sensitive in the detection of these compounds. The methodology was validated in terms of: linearity, selectivity, accuracy, precision, quantification limit, detection limit and robustness. The detection limit was less than 0,5 &mu;g.L-1. The accuracy and precision were adequate for testing the trace compounds. The drinking water samples were collected in the city of Suzano-SP, which belongs to Alto do Tietê, in this region lay Tietê river with predominant vegetation. The THMs compound found in drinking water at higher concentrations was chloroform where the spread of values found between 15,9 to 111,0 &mu;g.L-1 in drinking water.
188

Permethrin for Mosquito Control: Drinking Water Impacts and Treatment

Eckert, Lesley 16 December 2013 (has links)
"The goals of this study were (1) to evaluate the impacts of pesticides used for mosquito control on drinking water and (2) to investigate the removal of permethrin from water using activated carbon. A review of current literature on pesticide usage, toxicity, occurrence in the environment, and treatment techniques to remove pesticides from drinking water was conducted. The focus of the literature review was on pesticides used for mosquito control. Permethrin is a synthetic pyrethroid insecticide used extensively in the United States (US) for mosquito control and in agriculture, with approximately 2 million pounds applied each year. Permethrin was selected for investigation based on its widespread use in the US, its inclusion on the Contaminant Candidate List 3 (CCL3), its health hazards, and the lack of previous research on the removal of permethrin from drinking water. The removal of permethrin from water using powdered activated carbon (PAC) was investigated. Equilibrium adsorption experiments to assess removal of cis-, trans-, and total permethrin were conducted using two types of PAC (WPH 650 and WPH 1000). Initial total permethrin concentrations ranged from 2.0 to 4.6 ug/L. PAC doses ranged from 0.0 to 10 mg/L. Results showed that PAC addition is an effective method for removing permethrin from water. Total permethrin concentrations were reduced by 38% with 0.05 mg/L of PAC WPH 650, and reduced to below the detection limit with 3 mg/L of PAC WPH 650. Total permethrin concentrations were reduced by 35% with 0.05 mg/L of PAC WPH 1000 and by 83% with 5 mg/L of PAC WPH 1000. Results for cis- and trans- permethrin were similar. The Freundlich isotherm model provided appropriate fits to the data with an R-squared value of 0.91 for both WPH 650 and WPH 1000."
189

A Cluster-Based Randomized Controlled Trial Promoting Community Participation in Arsenic Mitigation Efforts in Bangladesh

George, Christine Marie January 2012 (has links)
Millions of villagers in Bangladesh drink water which exceeds the Bangladesh arsenic (As) standard of 50 micrograms per liter. Exposure to elevated levels of inorganic As (As) is associated with cancers of the skin, bladder, and lung, developmental effects, cardiovascular disease, skin lesions, and decreased children's intellectual functioning. Arsenic mitigation typically involves an outsider coming into a village to test the well water for As. After the results of the As test are provided this person typically leaves the village without providing the resources to address health concerns or give advice on mitigation options. In this dissertation, in an effort to provide ongoing resources on the health implications of As and to reduce As exposure, we sought to evaluate community level intervention strategies that could be used for successful As mitigation in Bangladesh. In Singair, Bangladesh, we conducted a household drinking water survey of 6649 households. The results of our survey indicated that 80% of wells were untested for As. Furthermore, we demonstrated that testing all of these untested wells would increase the number of households that lived with fifty meters of an As safe drinking water source by nearly 2.5 fold. In a cluster based randomized control trial (RCT) of 1000 households, we evaluated the effectiveness of having community members, compared to outside representatives, disseminate As education and conduct water As (WAs) testing. In 10 villages, a community member disseminated As education and provided WAs testing. In a second set of 10 villages an outside representative performed these tasks. Overall, fifty three percent of respondents with unsafe wells at baseline switched after receiving the As education and WAs testing intervention. There was no significant association observed between the type of As tester and well switching (Odds ratio (OR) =0.77; 95% confidence interval (CI) (0.37-1.61)). At follow-up, the average UAs concentrations for those with unsafe wells at baseline who switched to safe wells significantly decreased. In both intervention groups a significant increase in knowledge of As was observed at follow-up compared to baseline. The unavailability of As-safe drinking water sources in some villages was the most substantial barrier to well switching identified. The Hach EZ As field test kit measurements conducted by the As testers were highly correlated with laboratory results. This finding indicates that the As testers were able to accurately measure the WAs concentration of wells. Furthermore in our pilot study, the performance of the Econo-Quick (EC) kit, a new field WAs testing kit, was comparable to that of the commonly used EZ kit and the Wagtech Arsenator kit. The EC kit has the advantage of a substantially shorter reaction time of only 12 minutes in comparison to the 40 minutes required by these other kits. Through this dissertation, we have demonstrated that As education and WAs testing programs can be used as an effective method to reduce As exposure and increase As awareness in many As affected areas of Bangladesh. Furthermore, our findings indicated that many households are using tubewells that are untested for As therefore demonstrating the urgent need for access to water As testing services.
190

Policy Diffusion and Drinking Water Services in Latin America, 1980-2014

Larocque, Florence January 2018 (has links)
Understanding how domestic institutions and actors interplay with international and foreign influences is key not only to understand the politics of decision-making in the globalized world we live in, but also to understand why global policies – or policies promoted by transnational and international actors – may (or may not) be implemented and have the intended effects “on the ground.” This dissertation sets to disentangle the all too often conflated parts of these dynamics by separately addressing the domestic processes of adopting, enforcing, as well as, in certain cases, preparing policy change influenced from abroad. It does so through the lens of the politics of drinking water and sanitation in Latin America from 1980 to 2014 and consists in three independent papers. The first paper addresses the diffusion of politicized policies, and more precisely the privatization of drinking water and sanitation services. This paper highlights one overlooked dimension of policy diffusion processes and more specifically of privatization processes: the preparatory measures adopted (or not) by governments prior to privatization. It suggests that the ability of governments to adopt gradual preparatory measures depends on the time horizon of privatization deciders and the political cost this preparatory gradual policy change may entail for the process. Theoretically, it contributes to the neo-institutionalist literature by adding a “preparatory” type of change to the existing framework of gradual institutional policy changes. Substantively, it underlines the redistributive consequences of privatization processes and the political dynamics behind the level of political risk these reforms may entail. The second and third papers underline the multifaceted effects of state capacity on policy diffusion for non-politicized (or technical) policies through the empirical analysis of the domestic adoption and implementation of drinking-water quality standards following the promotion of the World Health Organization’s drinking-water quality guidelines. The second paper argues that strong state capacity tends to limit the adoption of a diffused policy that represents a strong domestic challenge. It contributes to the institutionalist literature by underlining the relevance to compare and measure state capacity on the basis of its resources (required to project its power), rather than on its ends or outcomes (which depend on the political choices that were made by the state). The third paper presents the other side of the coin of the impact of state capacity on diffusion of non-politicized policies, at the implementation step. At this step, strong state capacity gives the capacity to extensively implement a diffused policy, but implementation will remain partial if there are no external pressures on the sector. In weak states, policy diffusion can be both window-dressing and frame-shaping, depending on political dynamics. To be frame-shaping, it needs a sustained foreign capacity support (that can compensate for the weakness of the state) and strong external pressures. Overall, this thesis disentangles the policy diffusion process by highlighting that receiving states and actors are not only passive agents but also proactive ones, regarding the adoption, enforcement, and preparation of policy changes influenced from abroad. It also contributes to the understanding of two dimensions of water reforms in Latin America largely overlooked by the literature and policy studies: measures lessening the privatization shock and drinking-water quality standards. These issues, less salient than strongly politicized ones (like privatization itself), are as consequential in the life of states and their citizens, especially for their health and wellbeing.

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