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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.
61

DETERMINAÇÃO DE CAFEÍNA EM ÁGUAS SUPERFICIAIS COMO INDICADOR DE CONTAMINAÇÃO POR ESGOTO DOMÉSTICO

Silva, Juliana Aparecida da 05 September 2016 (has links)
Made available in DSpace on 2017-07-24T19:37:55Z (GMT). No. of bitstreams: 1 Juliana Aparecida da Silva.pdf: 2399008 bytes, checksum: e786a3c1c65773bda5c870d3130afee1 (MD5) Previous issue date: 2016-09-05 / Caffeine is suggested as a chemical indicator for the presence of domestic wastewater in freshwater systems, although it is not included in quality monitoring programs. Thus, it can be an excellent indicator of contaminant organic residues in urban streams frequently affected by sewage in Brazil. In this sense, the objective of this study was to evaluate the potential of caffeine as an indicator of domestic sewage contamination in surface waters of the Pitangui River Basin, in the city of Ponta Grossa, Paraná, Brazil. In the study, after the validation of the analytical methodology, a relationship was sought between caffeine in surface water and the effluent supply. Eight (8) surface water samples were collected in the Verde River, in the urban area (P1), upstream (P2) and downstream (P3) of the Sewage Treatment Station (STS), and two treated effluent samples of the STS. For the determination of caffeine, High Performance Liquid Chromatography (HPLC) was used after solid phase extraction in C18/18 cartridges with extractor volume of 6ml. The physical-chemical evaluations of the surface samples showed a decline in the water quality after the STS treated effluent input, observed mainly through the concentrations of total phosphorus (PT) and Biochemical Oxygen Demand (BOD) levels, above the established limits by legislation, after the effluent. Caffeine was quantified at points P2 and P3, with mean concentrations of 121,0 e 144,0 μg L-1. The results showed the relationship between the presence of caffeine and impaction by the inflow of raw sewage, or by the treated effluent from the STS. / A cafeína é sugerida como indicador químico para a presença de águas residuais domésticas em sistemas de água doce, embora não esteja incluída em programas de monitoramento da qualidade. Assim, pode ser um excelente indicador de resíduos orgânicos contaminantes em córregos urbanos frequentemente afetados por esgoto no Brasil. Nesse sentido, o presente trabalho teve como objetivo avaliar a potencialidade da utilização da cafeína como indicador de contaminação por esgoto doméstico em águas superficiais da bacia do Bacia do Rio Pitangui, no município de Ponta Grossa, Paraná (Brasil). No estudo, após a validação da metodologia analítica, buscou-se uma relação entre a cafeína em águas superficiais e o aporte de efluente. Foram realizadas 8 (oito) coletas de águas superficiais no Rio Verde, sendo em área urbana (P1), a montante (P2) e a jusante (P3) da Estação de Tratamento de Esgoto (ETE), além de duas coletas de efluente tratado da ETE. Para a determinação da cafeína foi utilizada a Cromatografia Líquida de Alta Eficiência (CLAE), após extração em fase sólida em cartuchos C18/18 com volume extrator de 6ml. As avaliações físico-químicas das amostras superficiais mostraram um declínio da qualidade da água após o aporte do efluente tratado da ETE, observado principalmente através das concentrações de fósforo total (PT) e dos níveis da Demanda Bioquímica de Oxigênio (DBO) acima dos limites estabelecidos pela legislação, após o aporte do efluente. A cafeína foi quantificada nos pontos P2 e P3, com concentrações médias de 121,0 e 144,0 μg L-1, respectivamente. Os resultados demonstraram a relação entre a presença da cafeína e a impactação pelo aporte de esgoto bruto, ou pelo efluente tratado da ETE.
62

O impacto do uso do solo na contaminação por agrotóxicos das águas superficiais de abastecimento público / The impact of land use in the contamination of the superficial waters of public supply by pesticides

Denise Piccirillo Barbosa da Veiga 05 May 2017 (has links)
Introdução: A qualidade e quantidade das águas superficiais estão diretamente relacionadas com as atividades econômicas presentes nas bacias hidrográficas e seus níveis de preservação. O aumento no uso de agrotóxicos pode contribuir para a contaminação do solo e da água, sobretudo em bacias hidrográficas agrícolas. A prevenção da contaminação dos mananciais é essencial para garantir a qualidade da água e diminuir os riscos à saúde humana, para tanto é preciso identificar como o uso e a ocupação do solo impactam os recursos hídricos, sua qualidade e seu equilíbrio hidrológico. Objetivo: Caracterização ambiental de duas bacias de mananciais de abastecimento público de forma a identificar áreas vulneráveis quanto à contaminação de agrotóxicos. Método: Aplicação do modelo hidrológico SWAT para caracterização da bacia e para simulação do ciclo hidrológico. Divisão da bacia hidrográfica em subbacias de acordo com o predomínio da ocupação do solo. Trabalho de campo para identificação de fontes pontuais de contaminação. Resultados: Foi verificado o impacto do uso e ocupação do solo no balanço hídrico das bacias. O escoamento superficial foi um dos principais meios de contaminação dos corpos dágua e esteve relacionado a presença de vegetação. Áreas de maior preservação apresentaram menor escoamento superficial enquanto àquelas com predomínio de agricultura e de solo exposto apresentaram valores maiores. A partir desses dados foram identificadas as áreas prioritárias para melhor gestão do uso de agrotóxicos por apresentarem potencial de contaminação dos corpos dágua. Conclusão: O modelo SWAT e as ferramentas de geoprocessamento se mostraram adequadas para a caracterização do uso do solo e os resultados fornecem subsídios para melhoria das ações de vigilância da qualidade da água nos municípios / Introduction: The surface waters quality and quantity are directly related to the economic activities present in the river basins and their levels of preservation. The increase in the use of pesticides can contribute to the contamination of soil and water, especially in agricultural watersheds. Preventing the contamination of water sources is essential to guarantee water quality and reduce risks to human health. Therefore, it is necessary to identify how the land use impacts water resources, their quality and their hydrological balance. Objective: Environmental characterization of two watersheds of public supply sources in order to identify vulnerable areas for the contamination of pesticides. Method: Application of the SWAT hydrological model for basin characterization and simulation of the hydrological cycle. Division of watershed in subbasins according to the predominance of the land use. Fieldwork to identify point sources of contamination. Results: The impact of land use and occupation on the water balance of the watersheds was verified. Surface runoff was one of the main means of contamination of water bodies and was related to the presence of vegetation in the area. Areas of greater preservation presented lower surface runoff while those with predominance of agriculture and exposed soil showed higher values. Priority areas for better use of agrochemicals were identified because they present potential for contamination of water bodies. Conclusion: The SWAT model and spatial tools were adequate for the characterization of land use and the results provide subsidies for the improvement of water quality monitoring actions in municipalities
63

Ocorrência e identificação de Cryptosporidium e Giardia em amostras de água superficial destinada ao abastecimento público do estado de São Paulo / Occurrence and identification of Cryptosporidium and Giardia from surface water catchment in Sao Paulo, Brazil

Breternitz, Bruna Suellen 01 March 2018 (has links)
Estudos de revisão sobre surtos associados à transmissão hídrica revelaram que os protozoários parasitas Cryptosporidium parvum e Giardia duodenalis (sinonímia: G. lamblia e G. intestinalis) são os principais responsáveis pelo maior número de casos registrados em todo o mundo. A contaminação das águas superficiais que servem ao abastecimento público por estes protozoários representa risco à saúde humana e animal, pois ambos parasitas apresentam resistência à cloração, processo convencional utilizado para desinfecção em Estações de Tratamento de Água (ETAs).Em vista desta lacuna, o presente estudo propõe identificar espécies e genótipos de Cryptosporidium e Giardia a partir de 128 amostras de águas superficiais de 11 mananciais do estado de São Paulo, de acordo com o Método 1623.1 (USEPA, 2012). Para identificar estes parasitas, foi realizada a recuperação dos (oo) cistos a partir de lâminas raspadas, seguindo o protocolo adaptado da USEPA, em seguida, utilizou-se o PCR em tempo real para identificar os genes 18S rRNA para Cryptosporidium e SSU para Giardia. Os resultados mostraram que a frequência de ocorrência desses protozoários nos pontos de captação foi de 29,7% para Giardia e 30,4% para Cryptosporidium. Os cistos estavam presentes em 10 dos 11 pontos de captação com frequências que variaram de 17 a 100%, e concentrações que variaram de <0,1 (Limite de Detecção=0,1) a 17,7 cistos /L, o que evidenciou a baixa qualidade dessas águas. Os oocistos ocorreram em uma frequência de 17 a 50% nas amostras positivas com concentrações que variaram de <0,1 a 11,5 oocistos/L. O ensaio de PCR em tempo real detectou um total de 81,4% (57/70) de amostras positivas para Cryptosporidium hominis-parvum-meleagridis e 21,4% (15/70) amostras positivas para Giardia duodenalis. A frequência de ocorrência desses agentes patogênicos e as altas concentrações de espécies antrópicas encontradas constituem um cenário de grande preocupação do ponto de vista da saúde pública, considerando-se que amostras foram coletadas dos locais de captação para o abastecimento público de água. / Review studies on waterborne outbreaks have been showing that Cryptosporidium parvum and Giardia duodenalis (synonym: G. lamblia and G. intestinalis) are the primarily responsible for the highest number of the cases recorded worldwide. Contamination of surface waters catchments by these protozoa is a risk factor to human health because both parasites are resistant to chlorination, which is a conventional process used for disinfection in water treatment plants (WTP). The present study aimed to identify species of Cryptosporidium and Giardia recovered from surface water catchment samples from 11 municipalities from the State of São Paulo, totalizing 128 samples. Quantification of both parasites was carried out according to method 1623.1 (USEPA, 2012). In order to identify parasites, the recovering of (oo)cysts from slides followed USEPA´s protocol by scraping slides, then Real Time PCR using the 18S rRNA genes for Cryptosporidium and SSU for Giardia were carried out. Results showed that the frequency of occurrence of these protozoa at the catchment points was 29,7% for Giardia and 30,4% for Cryptosporidium. Cysts were present in 10 of 11 catchments points with frequencies varying from 17 to 100% with concentrations ranging from <0.1 (Limit of Detection=0.1) to 17.7 cysts/L, which put in evidence the low quality of water. Oocysts occurred in a frequency from 17 to 50% in positive samples with concentrations ranging from <0.1 (LD) to 11.5 oocysts/L. The real-time PCR assay detected a total of 81.4% (57/70) of positive samples for Cryptosporidium hominisparvum- meleagridis and 21.4% (15/70) samples positive for Giardia duodenalis. The frequency of occurrence of these pathogens and the high concentrations of anthropic species found is a concerning scenario for human health, considering samples have been collected from catchment sites for public water supply.
64

Innovative and Efficient Simulation-Optimization Tools for Successful Groundwater Management and Conflict Resolution

Timani, Bassel 01 May 2015 (has links)
Decision makers' conflicts about the validity of a single simulation model and inefficiencies of existing response matrix methods (RMM) hinder adopting successful groundwater management plans. We speed up the process by proposing a hybrid RMM that is most efficient for situations in which optimizable stimuli can vary through consecutive periods of uniform duration interspersed with periods of different duration. We use the hybrid RMM within Simulation-Optimization (S-O) models to develop optimal water management strategies. For the tested problems, the hybrid RMM requires as much or 63-89% less computation time than other RMMs. Second, we propose Multi-Conceptual Model Optimization (MCMO) that can help stakeholders reach a compromise strategy instead of agreeing on the validity of a single model. MCMO computes optimal strategies that simultaneously satisfy analogous constraints and bounds in multiple numerical models differing by more than parameter values. Applying MCMO to Cache Valley (Utah, USA) reveals that protecting local ecosystem limits the increased groundwater pumping to satisfy only 40% of projected water demand increase using two models. To successfully and sustainably manage Cache Valley aquifer, we evaluate sustained yield strategies (SYS) and quantify the resilience of a computed SYS. We maximize the number of new residents who can have their indoor and outdoor uses satisfied, subject to constraints on aquifer-surface waters conditions, and limiting new residents to projected increases in population (PIiP). furthermore, we examine the effect of optimization approach and sequiencing, temporally-lagged spatially distributed return flow that is a function of optimal groundwater use, and the acceptability time evaluation on the optimal yield strategy. Cache Valley aquifer can sustainably satisfy the outdoor water demand of 74%-83% and the indoor water demand of 83%-100% of the PIiP. We quantify deterministic resilience Rd(A,T,SV)=P to evaluate how completely an aquifer condition (SV) recovers after the end of climatic anomaly (A), by recovery time (T). Simulation predicts that Cache Valley aquifer system resiliences to a 2-year drought are Rd(2YD, 3 yrs, Overall) = 93% and Rd (2YD,≥8,Overall) ≥ 95%. Proportionally reducing pumping rates by 25% through the time horizon of the simulation increases the overall resilience to 96% within 3 years.
65

Chemical Changes in Groundwater of Northern Utah Valley, Utah

Fairbanks, Paul E. 01 May 1982 (has links)
Northern Utah Valley is one of the fastest growing areas of Utah and has increasing needs for domestic, industrial, and agricultural water. To meet these needs, groundwater and surface water systems must be understood to maximize their use. Chemical studies of the sediment mineralogy and related water-chemistry give insight to the movement of the water. There are three major aquifers present in the valley: shallow Pleistocene; deep Pleistocene; and Tertiary. They are composed of sands and gravels and are separated by confining layers (aquitards) composed mostly of clay. Along the flanks of the bordering mountains there are undifferentiated aquifers which act as conduits supplying water for aquifers in the valley. Sediment samples from aquifers and confining layers were obtained by rotary and cable-tool drilling. X-ray diffraction analyses showed that the aquifers are mainly composed of quartz, calcite, and dolomite, whereas the con fining layers contain illite and montmorillonite with some kaolinite, quart z and calcite. One hundred nine water samples were collected in this study from s ur face water, spring water, undifferentiated aquifer water, shallow Pleistocene aquifer water, deep Pleistocene aquifer water and Tertiary aquifer water. Results show that the ground water system has several geochemical cells in each aquifer, due to diverse areas of recharge. Three major water types can be identified in different areas of the shallow Pleistocene aquifer, three in different areas of the Tertiary aquifer, and four in different areas of the deep Pleistocene aquifer. The differences in these water types are related to the composition of the mountain recharge areas and positions of faults within the valleys. The aquifer composition exerts relatively little influence on the chemistry of the ground water. Mountains of predominantly carbonate rocks produce recharge waters rich in calcium and bicarbonate. Mountains of predominantly granitic rocks produce recharge water low in mineral content. Valley sediments near major faults produce highly mineralized waters.
66

The structure of langmuir monolayers probed with vibrational sum frequency spectroscopy

Gurau, Marc Cory 29 August 2005 (has links)
Langmuir monolayers can be employed as simple model systems to study interactions at surfaces. Such investigations are important to fields ranging from biology to materials science. Herein, several aspects of these films and their associated water structure have been examined with vibrational sum frequency spectroscopy (VSFS). This second order nonlinear optical spectroscopy is particularly well suited for simultaneous investigations of the monolayer and the associated water structure with unprecedented surface specificity. The structures of these systems were altered through the control of experimental parameters including monolayer pressure, subphase temperature, pH and ionic content. Thermodynamic information about structural changes in a fatty amine monolayer's hydrophobic region was obtained by observation of the pressure and temperature dependence of the monolayer's solid to liquid phase transition. Further studies used the coordination of divalent cations to acid monolayers to perturb the water layers nearest to the film which enabled a better understanding of the water related VSFS features from these hydrophilic interfaces. Information from both the monolayer and water structure was then combined in order to examine the role of water in mediating ion-biomaterial interactions, often expressed in terms of the Hofmeister series.
67

EstimatingChloride concentration in surface water and groundwater duet to deicing salt application

Thunqvist, Eva-Lotta January 2003 (has links)
A road in operation along with its traffic can pose aserious pollutant threat to groundwater and surface water inits vicinity. Examples of pollutants are metals from thecorrosion of vehicles, rails and poles and the wear of roadsurfaces and tyres; hydrocarbons from the wear of roadsurfaces, tyres, exhausts, oils; sodium chloride from roadsalt; and hazardous goods discharged in accidents. Eventuallypollutants that are not degraded or retarded in soil will reachgroundwater and surface water. The chloride ion in deicing saltis a good tracer. It is conservative and highly soluble and notsubject to retardation or degradation. If the chlorideconcentration has increased in groundwater or surface water inthe vicinity of a deiced road, other road-related pollutantsmight also be present in the water. Increased chloride concentrations have been observed inseveral water supplies, in groundwater as well as in surfacewater, since the 1970s. The number of affected water supplieshas also increased. The increase in chloride concentration inwaters is concurrent with the increase in deicing saltapplication and it is clear that most of the increase is due tothe application of deicing salt. The thesis presents a simple tool that quantified theincrease in chloride concentration for water in a catchmentarea, based on a steady-state water balance. The data wereefficiently processed and presented as maps with GIS. At aregional catchment area scale, substantially increased chlorideconcentrations were calculated. The variation between catchmentareas was verified by a national monitoring programme of lakes.Deicing salt application was estimated to account for more thanhalf of the total chloride load for a catchment area in the midsouth of Sweden. A distributed dynamic method was used to evaluate thetemporal and spatial variation of the chloride concentration inan aquifer. The distributed dynamic approach integrated thespreading of deicing salt from the road with the infiltrationin the unsaturated zone in the soil, which in turn wasintegrated with the groundwater flow. The simulation was runfor a 40-year period and showed a potential to describe aspecific system. <b>Keywords:</b>road, deicing salt, monitoring, chloride,catchment area, river basin, simulation, GIS, groundwater,surface water
68

The role of polymer flocculants in microfiltration of surface water

January 2012 (has links)
Polymer flocculants, traditionally used with primary coagulant to enhance flocculation and sedimentation, are used in the coagulation-/microfiltration process as well assuming they can improve membrane performance similarly. However, there are several uncertainties concerning the use of polymer flocculants in the coagulation-microfiltration process. First, polymer flocculants may not have measurable effect on turbidity removal, because microfiltration membranes can remove significantly smaller particles than those removed by the conventional treatment process. Second, the effect of using polymer flocculants on NOM removal has been controversial. Although a number of studies reported improved NOM removal when polymers were used, others reported no or negative impact of polymers on NOM removal. Third, polymer flocculants are high molecular weight organic compounds. When carried over to membrane residual polymers can potentially foul the membranes. Finally, the use of polymer flocculants will change floc properties (i.e. size, fractal dimension, and stickiness) and subsequently bring uncertain effect on cake layer resistance. Therefore, the role of polymer flocculants in coagulation-microfiltration system needs to be carefully assessed for system optimization. In the reported research, three types of polymer flocculants with different charge and molecular weights were tested for comprehensively evaluating the impact of polymer flocculants on the performance of coagulation-microfiltration of surface water. Operation conditions such as inline filtration, direct filtration, and filtration with sedimentation were included. Two membrane reactors were designed to study the mechanism through which polymer flocculants affect the performance of coagulation-microfiltration systems. The result demonstrated that the use of polymer flocculants provides little to no benefit to turbidity and NOM removal in most cases, but pDADMACs can enhance NOM removal if applied properly; All polymer flocculants significantly increased membrane fouling except for pDADMACs when sedimentation proceeds MF; Polymer flocculants increase deposition/attachment of floc particles on the membrane surface through both adsorption of residual polymer on the membrane surface and polymer molecules on the floc particle surface; Even though polymers form larger and more fractal floc particles, they did not have notable impact on cake layer structure.
69

Performance of a Surface-Flow Constructed Wetland Treating Landfill Surface-Water Runoff

Hick, Justin 11 June 2013 (has links)
Landfills are a major potential source of groundwater and surface-water contamination. The compounds that can leach from landfilled materials include dissolved organic matter, inorganic macrocomponents, heavy metals, and xebobiotic organic compounds. Landfill surface-water runoff poses a threat to the environment due to high mobility, but has not been rigorously characterized with regards to common pollutants found in landfills. It is well documented that constructed wetlands can serve as an effective treatment option for many pollutants found in landfills. The Napanee Landfill has constructed a wetland in order to treat surface-water runoff coming off the landfill. The objectives of this study were to: 1) characterize the water chemistry of surface-water runoff for an inactive landfill; 2) evaluate the treatment potential for the constructed wetland system at the Napanee Landfill; and, 3) recommend design, maintenance, and operative improvements to enhance effluent water quality. The analysis of the landfill surface-water runoff entering the Napanee Landfill constructed wetland included the pollutants nitrate, ammonia, sulphate, phosphorus, and chloride. The median inflow and outflow concentrations for all of the observed pollutants did not exceed Canadian federal or provincial water quality guidelines. There were sampling days where ammonia, phosphorus, and chloride exceeded guidelines at the inflow and days where ammonia and chloride exceeded guidelines at the outflow. The only pollutant that saw a statistically significant decrease in concentrations was sulphate, with a change of 38% from the inflow to the outflow. Other changes of note were nitrate and phosphorus concentrations increasing by 50% and 23% respectively from the inflow to the outflow. There are a variety of improvements that can be made to the Napanee Landfill constructed wetland that would increase the treatment efficiency of ammonia. Incorporating a vertical-flow wetland would increase available surface area for nitrifying bacteria growth and would provide more oxygen for nitrification processes; both would increase the potential for significant ammonia treatment. Overall, the concentrations of the pollutants found in the surface-water runoff coming off of the Napanee Landfill constructed wetland did not pose a significant threat to the environment at the time of sampling and treatment processes were only successful in reducing sulphate pollutant concentrations.
70

Isotopic records of meteorological and atmospheric conditions from sub-annually resolved tree-ring cellulose, precipitation, and surface waters

Dodd, Justin Paul 05 July 2006
In recent decades, there has been increased global concern about observed climate change; however for future climatic impacts and anthropogenic forcings of climate change to be realistically predicted, natural climate variability in the past needs to be better understood. The aim of this research is to develop quantifiable proxy records of past climate change through the calibration of isotope values in modern surface waters and tree ring cellulose with meteorological and atmospheric records. Terrestrial proxy records that utilize oxygen and hydrogen isotope values to reconstruct paleoclimatic and paleohydrologic conditions are limited by a paucity of data on the modification of surface water isotope values prior to sequestration into proxy material. To address this gap in our knowledge and determine the most appropriate study sites, this research focuses on isotopic records preserved in surface water reservoirs, precipitation, and tree-ring cellulose. In the first study, δD, δ18O, and deuterium-excess values were determined for lakes and rivers from Tasmania, southeastern Australia. <p> The second focus of this research was to calibrate the δ18O, δD, and δ13C values of tree-ring cellulose from North America with instrumental records. A new high-resolution sampling procedure that uses a robotic micromilling device to very precisely map and sample along growth rings in trees is discussed. Additionally, a seasonally resolved (early/late wood) 110-year record of δ18O values from tree-ring α-cellulose from spruce species (<i>Picea mariana</i> and <i>P. glauca</i>) from east-central Saskatchewan, Canada is compared to growing season precipitation δ18O values, temperature, and relative humidity. The δ18O time series from α-cellulose display a high correlation with growing season precipitation isotope values (r = 0.86). δ18O α-cellulose time series from a white spruce (<i>Picea glauca</i>) also records seasonal changes in atmospheric circulation associated with the position of the circumpolar vortex and dominate modes of atmospheric variability such as the North Atlantic Oscillation and Pacific Decadal Oscillation.

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