Dissertations / Theses on the topic 'Surface Water'
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Sparks, Tim. "Integrated surface water-groundwater modelling : linking surface water and groundwater using DIVAST-SG." Thesis, Cardiff University, 2007. http://orca.cf.ac.uk/54617/.
Full textCluff, C. Brent. "Slowsand/Nanofiltration of Surface Water." Arizona-Nevada Academy of Science, 1991. http://hdl.handle.net/10150/296460.
Full textSince the spring of 1988 the University of Arizona has conducted nanofiltration research. The major emphasis has been the treatment of both Colorado River Water and municipal effluent. The work has been sponsored by the John F. Long Foundation Inc. and the Consolidated Water Utilities, Phoenix Az. Nanofiltration is a low pressure form of reverse osmosis. It operates at about 1/3 the pressure and 3 times the flux rate of older brackish water reverse osmosis systems. This reduces both the cost as well as the operating costs to approximately 1 /10 of the older reverse osmosis systems. The City of Ft Myers is projecting costs as low as $0.50-0.60/1000 gallons for their 20 MGD plant. Nanofiltration treats water the way it needs to be treated to meet the Environmental Protection Agency's (EPA) present minimum contamination levels (MCL) as well as projected future levels. Nanofiltration removes most of the bivalent inorganic molecules such as calcium and magnesium as well as some monovalent molecules such as sodium and chloride. It also removes pathogens and dissolved organics, thus reducing the trihalomethane formation potential (THMFP). The research on recharged effluent municipal effluent below the 91st Avenue Plant in Phoenix has shown the value of nanofiltration for reclaiming municipal wastewater to potable standards. A 20,000 GPD slowsand /nanofiltration pilot plant at Apache Junction has shown the effectiveness of the treatment on Colorado River Water at a 95% recovery over the past 2 years.
Gustavsen, Jostein, and Dan Lewi Harkestad. "Visualization of water surface using GPU." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10116.
Full textSeveral methods for simulating a body of water and a water surface has been investigated. A method by Layton & van de Panne based on a simplification of the Navier-Stokes equations was selected. A number of simplifications was made to increase the performance of the method, and it was implemented on the programmable graphical processing unit (GPU) using the Jacobi method to solve the linear equations. A conjugate gradient solver was also implemented on the GPU. The performance of the methods were measured and recorded.
Chalew, Talia Weinberg Howard. "Chemical indicators of surface water pollution." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,662.
Full textTitle from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Masters of Science in the Department of Environmental Sciences and Engineering." Discipline: Environmental Sciences and Engineering; Department/School: Public Health.
Williams, W. A. "Evaporation from a weeded water surface." Thesis, University of Newcastle Upon Tyne, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371922.
Full textCluff, C. Brent, Charles P. Gerba, and Gary L. Amy. "Slow Sand/Nanofiltration of Surface Water." Water Resources Research Center. The University of Arizona, 1990. http://hdl.handle.net/10150/306475.
Full textIntroduction: Through the studies published in Drinking Water and Health (1977) the nation has become more aware of the carcinogenic nature of the byproducts of disinfection such as trihalomethanes. Trihalomethanes are formed when the disinfectant chlorine reacts with the precursors, humic and fluvic acids that are naturally occuring in all surface water. The Environmental Protection Agency (EPA) has set a minimum contaminent level of 100 ppb on THM's that many in the health agencies feel need to be lowered. The problem is that when the MCL's are lowered utilities will be enclined to chlorimines and chloride dioxide which have been found to be mutagenic. Drinking Water and Health (1987) found the Suggested No-Adverse Response Levels (SNARLs) for chioramines for a child is 0.166 ppm, for an adult it is 0.581. The SNARL for chlorine dioxide is 0.06 ppm for a child and 0.210 ppm for an adult. These levels for utilities are virtually impossible to maintain and still have a residual at the end of the system.
Grundy, Ian H. "Air flow near a water surface /." Title page, table of contents and summary only, 1986. http://web4.library.adelaide.edu.au/theses/09PH/09phg889.pdf.
Full textZhao, Yajing S. M. Massachusetts Institute of Technology. "Dropwise condensation of water and low surface tension fluids on structured surfaces." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/118679.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (pages 55-57).
Condensation is a ubiquitous process often observed in nature and our daily lives. The large amount of latent heat released during the condensation process has been harnessed in many industrial processes such as power generation, building heating and cooling, desalination, dew harvesting, thermal management, and refrigeration. Condensation has two modes: dropwise mode and filmwise mode. Although it has been known for decades that dropwise condensation outperforms filmwise condensation in heat transfer owing to the droplet shedding effects which can efficiently reduce thermal resistance, filmwise condensation still dominates industrial applications currently due to the high costs, low robustness and technical challenges of manufacturing dropwise coatings. During water condensation, dropwise mode can be readily promoted with thin hydrophobic coatings. Superhydrophobic surfaces made out of hydrophobic coatings on micro-or-nano-engineered surfaces have shown further heat transfer enhancement in dropwise condensation of water; however, the applications of these micro- or nanoscale structured surface designs have been restricted by the high manufacturing expenses and short range of subcooling limit. Recent studies have shown that the combination of millimeter sized geometric features and plain hydrophobic coatings can effectively manipulate droplet distribution of water condensate, which provides opportunities to locally facilitate dropwise condensation at relatively low manufacturing expenses as compared to those delicate micro- and nano-structured hydrophobic surfaces. Low surface tension fluids such as hydrocarbons pose a unique challenge to achieving dropwise condensation, because common hydrophobic coatings are not capable of repelling low surface tension fluids. Recent development in lubricant infused surfaces (LIS) offers promising solutions to achieving dropwise condensation of low surface tension fluids by replacing the solid-condensate interface in conventional hydrophobic coatings with a smooth lubricant-condensate interface. However, only a few experimental studies have applied LIS to promoting dropwise condensation of low surface tension fluids (y as low as 15 mN/m). In this work, we investigated dropwise condensation of both water (y ~ 72 mN/m) and a low surface tension fluid, namely butane (y - 13 mN/m) on structured surfaces. For water condensation, we studied the effects of millimeter sized geometric structures on dropwise condensation heat transfer under two different environments: pure vapor and an air-vapor mixture. Our experimental results show that, although convex structures enable faster droplet growth in an air-vapor mixture, the same structures impose the opposite effect during pure vapor condensation, hindering droplet growth. We developed a numerical model for each case to predict the heat flux distribution along the structured surface, and the model shows good agreement with experimental results. This work demonstrates that the effects of geometric features on dropwise condensation are not invariable but rather dependent on the scenario of resistances to heat and mass transfer in the system. For butane condensation, based on a design guideline we recently developed for lubricant infused surfaces, we successfully designed an energy-favorable combination of lubricant and structured solid substrate, which was further demonstrated to promote dropwise condensation of butane. The fundamental understanding of dropwise condensation of water and low surface tension fluids on structured surfaces developed in this study provides useful guidelines for condensation applications including power generation, desalination, dew harvesting, and thermal management.
by Yajing Zhao.
S.M.
Fraser, Justin. "Surface tension driven water pumping : a bio inspired passive water pump." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97105.
Full textENGLISH ABSTRACT: The purpose of this study is to construct and test a surface tension driven water pump. The surface tension driven water pump is a passive water pump which uses a similar mechanism to that of trees to pump water. This study was conducted at the Department of Mechanical and Mechatronic Engineering at the University of Stellenbosch. For the study an extensive literature survey was done encompassing aspects such as water properties, surface tension (basic principles, capillary forces, temperature and contaminant effects, wettability), bubble formation (nucleation theory and tensile strength of water) and, finally water and mineral transport in trees (plant structures and mechanisms, limiting factors, misconceptions and organic substance transport). Previous work by botanists who demonstrate the transpiration mechanism needed for water transport in trees was also considered. The study further required the development of a theoretical thermal-hydraulic model to simulate the pumping performance for the surface tension driven water pump. The developed water pump was also experimentally tested with particular focus on design improvement, pumping performance, pump behaviour, potential pumping head as well as water collection capability. The experimental data was statistically analysed by multi-linear regression. Both the experimental data and statically generated predictions were compared to the theoretical thermal-hydraulic model. The results show that a working surface tension driven pump was constructed. Evaporation rates of up to 400 mL/hr.m2 were obtained, with pumping head heights reaching up to 1.8 m and a maximum pump functional lifespan of 13 days. The results further suggest that there is a good correlation between the various statistical fits and the experimental data. The developed theoretical thermal-hydraulic model was also found to be in good agreement with the experimental results. A sensitivity analysis of the theoretical and statistical models showed that the statistical models fairs poorly under extrapolation. Additionally, the mechanistic causes of pump failure as well as the effect of heat and pumping head on water pumping performance were identified. Thereafter, the water collection efficiency was established to be 98% on average. Further testing revealed that the pumping performance of larger area or multiple grouped “leaves” are less accurately predicted with the theoretical model than a single “leaf”. In conclusion, the results provide some support that the surface tension driven pump may be used as a water transport system in an artificial photosynthesis project, if the functional lifespan of the pump can be greatly improved. It is recommended that a more rigid hydrophilic material be used in the “leaf” interface and that multiple narrower conduits be used instead of a single larger pipe. Additional future work may include the development of pit-like structures to prevent air spreading throughout the system as well as a simple mechanism for evaporative control.
AFRIKAANSE OPSOMMING: Die doel van hierdie ondersoek is om 'n oppervlakspanning-aangedrewe waterpomp te bou en te toets. Die oppervlakspanning-aangedrewe waterpomp is ‘n passiewe waterpomp wat gebruik maak van ‘n meganisme soortgelyke aan dié van bome om water te pomp. Hierdie ondersoek is by die Departement Meganiese en Megatroniese Ingenieurswese by die Universiteit van Stellenbosch uitgevoer. Vir die ondersoek is 'n uitgebreide literatuurstudie gedoen wat aspekte soos water eienskappe, oppervlakspanning (basiese beginsels, kapillêre kragte, die uitwerking van temperatuur, onsuiwerhede asook benatbaarheid), lugborrelvorming (kernvormingsteorie en die treksterkte van water) en uiteindelik water- en mineraalvervoer in bome (plantstrukture en -meganismes, beperkende faktore, wanpersepsies en die vervoer van organiese stowwe) insluit. Vorige navoring deur plantkundiges, wat die watervervoermeganismes in bome demonstreer, is ook in ag geneem. Die ondersoek het die ontwikkeling van 'n teoretiese termies-hidrouliese model ingesluit, wat gebruik is om die oppervlakspanning-aangedrewe waterpomp se werking te voorspel. Die waterpomp is ook eksperimenteel getoets met die fokus op ontwerpverbetering, pompwerkverrigting, pompwerking, potensiële pompopvoerdrukhoogte sowel as die waterversamelingsvermoë. Die eksperimentele data is statisties ontleed deur middel van meervoudige liniêre regressie. Beide die eksperimentele data en statisties-gegenereerde voorspellings is vergelyk met die teoretiese termies-hidrouliese-model. Die resultate toon dat 'n werkende oppervlakspanning-aangedrewe pomp gebou is. ‘n Verdampingstempo van tot 400 mL/hr.m2, pompopvoerdrukhoogte van tot 1.8m en 'n maksimum funksionele pompleeftyd van 13 dae is bereik. Die resultate dui verder daarop dat daar 'n goeie korrelasie tussen die verskillende statistiese lynpassings en die eksperimentele data is. Die teoretiese termies-hidrouliese-model wat ontwikkel is, toon 'n goeie ooreenkoms met die eksperimentele resultate. 'n Sensitiwiteitsanalise van die teoretiese en statistiese modelle het getoon dat die statistiese modelle swak voorspellings maak as geëkstrapoleerde data gebruik word. Verder is die meganismes wat pompweiering veroorsaak, die effek van hitte asook die effek van pompopvoerdrukhoogte op die pomp se werkverrigting geïdentifiseer. Daarna is die doeltreffendheid van waterversamelingsvermoë vir die waterpomp vasgestel op gemiddeld 98%. Verdere toetse het getoon dat die pompwerkverrigting van groter gegroepeerde "blare" minder akkuraat met die teoretiese model voorspel word as vir 'n enkele "blaar". Ten slotte: Die resultate toon dat die oppervlakspanning-aangedrewe waterpomp as 'n water vervoer stelsel gebruik kan word in 'n kunsmatige fotosinteseprojek, indien die funksionele leeftyd van die pomp verbeter kan word. Dit word aanbeveel dat 'n sterker hidrofiliese materiaal in die "blaar"-koppelvlak gebruik word en dat verskeie nouer leipype gebruik word in plaas van 'n enkele groter pyp. Bykomende toekomstige werk kan die ontwikkeling van put-agtige strukture insluit wat die verspeiding van lug deur die hele stelsel voorkom, sowel as 'n eenvoudige meganisme wat die verdampingstempo beheer.
Odeh, Rabah Y. "Simulation and forecasting of surface water quality." Ohio : Ohio University, 1992. http://www.ohiolink.edu/etd/view.cgi?ohiou1172865698.
Full textSen, Evrim. "Water Dispersed Epoxy Resin For Surface Coatings." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1211051/index.pdf.
Full textC, and stirred for 4 hours. Then the temperature was increased to 80oC and kept for 2 hours. Maleinized fatty acids were then introduced, and the reaction was carried out at 90oC for 10 hours. 1,4-dioxane was used for the removal of the water, which forms as the byproduct. Then the driers were added. The carboxylic groups of the maleinized fatty acid were neutralized by morpholine and the product was dispersed in water. The varnish was applied on test panels and left for air-drying for 24 hours and then baked at 140°
C for 5 hours. The free epoxy content was determined by pyridinium-chloride titration and it was seen that all the epoxy groups reacted. Also, produced fatty acid was characterized by FTIR spectroscopy and maleinized fatty acid was characterized by H-NMR and FTIR spectroscopy. Hardness, bending, impact resistance, gloss, and abrasion resistance tests were carried out on hardened varnish specimens. The samples generally showed good mechanical and physical properties. While the baking time was increased the hardness of product increased. Samples showed superior impact resistance, gloss, and flexibility.
Ogutverici, Abdullah. "Triclosan Removal By Nanofiltration From Surface Water." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615617/index.pdf.
Full textprü
Reservoir (Ankara) water was used as raw water. Effect of natural organic matter (NOM) content of raw water on TCS removal is searched through addition of humic acid (HA) into the raw water as to represent for NOM. Steady state permeate fluxes are monitored throughout the experiments to explore the flux behavior of the membranes. During the experiments, performance of the membranes is assessed by monitoring TCS, as well as other water quality parameters, such as UVA254 and total organic carbon (TOC) in the feed and permeates waters. Results obtained put forward that TCS removal by NF membrane is not as same as reported in the literature. In the literature, membrane removal efficiency is reported as above 90%. However, this study proved that this would be true if and only if one does not considers the adsorption of TCS by the system itself, in the absence of membrane. It is now clear that, because of adsorption of the TCS onto the experimental set up (feed tank, pipings etc.)
the real TCS removal efficiency of the nanofiltration is around 60-70%.
Braga, Maria Cristina Borba. "Surface water quality modelling of mercury contamination." Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396307.
Full textAsh, Philip Andrew. "Surface freezing in surfactant/alkane/water systems." Thesis, Durham University, 2011. http://etheses.dur.ac.uk/843/.
Full textPierre, Viera Marie. "New water-soluble polymers for surface applications." Thesis, Durham University, 2000. http://etheses.dur.ac.uk/4205/.
Full textChinnaswamy, Arulmani. "Water vapour and sea surface temperature retrievals." Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270328.
Full textCASTAGNOLI, JOAO PAULO. "NUMERICAL IMPLEMENTATION OF ACOPPLING SURFACE WATER: GROUNDWATER." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=11037@1.
Full textCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
A relação entre os processos hidrológicos de escoamento superficial e subterrâneo apresenta uma grande variabilidade espacial e temporal. Podendo ser representado de forma qualitativa como parte sequêncial do ciclo hidrológico, estes processos, demostram sua grande dependência e importância nos estudos de balanços hídricos. Visando uma representação quantitativa, este trabalho faz o acoplamento, entre os modelos numéricos de escoamento superficial e de fluxo em meios porosos. Para o meio poroso adotou-se o modelo numérico SWMS_3D (Simunek et al, 1995), o qual resolve a equação de Richards, para fluxo em meios porosos saturados e não saturados nas três dimensões. Na simulação da dinâmica superficial, foram desenvolvidos dois modelos derivados das equações de Saint- Venant: o modelo da Onda Cinemática e o modelo de Difusão. Para a solução numérica foi empregado o método dos elementos finitos através da formulaçao de Galerkin, adotando uma malha tridimensional de elementos tetraédricos, formando uma sub-malha de elementos triangulares na superfície. O modelo de escoamento superficial emprega a malha triangular e interage com o programa SWMS_3D modificado (que utiliza a malha de tetraédros) através das imposições das condições de contorno transientes. Este, responderá com uma parcela de fluxo correspondente à recarga ou descarga no contorno a cada passo de tempo. Com isso, o modelo gerado é capaz de quantificar espacialmente e temporalmente as cargas de pressão em todos os pontos do domínio de estudo.
While analyzing the interaction between the hydrological processes of surface and groundwater flow, it is seen that there is a big difference in its interaction in the space and time. These processes can be represented in a qualitative form as part of the hydrological cycle, demonstrating its dependences and importance in the hydrological balance. This work does the numerical coupling of the surface and groundwater flow. This work adopted the SWMS_3D numerical model (Simunek et. al., 1995), which resolves the Richards equation for saturated and non saturated porous media flow in 3D. In order to simulate the superficial dynamic flow, two models from Saint-Vennat equation were developed, these models are: the cinematic wave model and the diffusion model. These two models consider the average outflow in sections in a 2D scenario. For the numerical solution the finite element method was adopted through the Galerkin formulation. Adopting a 3D domain mesh of tetrahedral elements, seen from above, in 2D, we can see a triangular element mesh. The superficial flow model uses the triangular mesh and iterates with the SWMS_3D modified software, which uses the tetrahedral elements mesh. This was done by changes in the boundary conditions to the models. The SWMS_3D will answer with a flow portion corresponding to a sink or source action in the surface, in each time step. Finally the generated model is able to quantify in space and in time the pressure head in the study domain.
Bedard, Robert J. A. "Laboratory scale experiments with water surface waves." Thesis, University of Hull, 2013. http://hydra.hull.ac.uk/resources/hull:7242.
Full textWu, Liuming. "Surface complexation at calcium mineral-water interfaces." Doctoral thesis, Luleå, 1994. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-25727.
Full textGodkänd; 1994; 20070429 (ysko)
Illiash, O. E., and S. S. Sen. "Investigation of surface water bodies Poltava region." Thesis, Сумський державний університет, 2012. http://essuir.sumdu.edu.ua/handle/123456789/30169.
Full textKirby, Laura Rebecca. "Surface Water Impacts from Active Underground Mining." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23290.
Full textThe SDPS program is used to conduct an analysis of ground movements to assess optimal barrier pillar size for stream protection. Typical analytical and empirical methods used in mine planning were compared against SDPS methods to ensure the validity and advantage to the use of SDPS for this purpose.
Finally, underground mining effects on stream chemistry and health were explored by studying the heavily mined and industrialized watershed of Dumps Creek located in Russell County, Virginia. This watershed has been identified as being impaired since the Virginia 303(d) List of Impaired Waters was created in 1994. Currently, there are two pumps staged in the headwaters region of Dumps Creek that help to maintain water levels in an inactive underground mine. The pumping is necessary to control methane levels that rising water could force into an active underground mine that lies stratigraphically above the inactive mine. Water is pumped on an as-needed basis and discharges directly into Dumps Creek. Historic measurements of stream conductivity and benthic health scores were compared to assess whether a correlation exists between the two measurements. These measurements were compared based on regulatory decisions that emphasized that conductivity is a direct indicator of stream health in all watersheds.
Scientific contributions associated with this research include: Further developments in the use of SDPS programming in order to account for stream protection on a case by case basis for both mine panel and surface water protection by optimizing barrier pillar size in relation to a nearby stream; the analysis of available and currently obtained water chemistry data in a mining impacted watershed in attempt to further research to appropriately characterize and mitigate specific problems in order to improve stream health; and, assessment of the complexity of water chemistry impacts from underground mining as related to stream health indicators in different chemically dominated watersheds.
Master of Science
Gunukula, Sampath Reddy. "ELECTROCOAGULATION/FLOTATION TREATMENT OF SYNTHETIC SURFACE WATER." Cleveland State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=csu1304363574.
Full textMorehead, Donald. "Spatiotemporal Patterns of Contamination in Surface Water." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1572879201471779.
Full textJones, Cullen Brandon. "Groundwater-Surface Water Interactions near Mosier, Oregon." PDXScholar, 2016. https://pdxscholar.library.pdx.edu/open_access_etds/3414.
Full textPERICO, ROBERTA. "GROUNDWATER-SURFACE WATER INTERACTION IN ALPINE CATCHMENT." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/374727.
Full textThe recognized evidence of global warming demands assessment of the present and future water cycle in Europe and worldwide. Recently, evidence of modified hydrological regime in the Alps under climate change has been documented. However, according to the IPCC Fifth Assessment Report, it is still necessary to deepen our understanding of the impact of climate change and land use on groundwater storage in the alpine catchment areas. A major limitation to the analysis of the surface water-groundwater interaction in alpine terrain are the difficultly of data acquisition as well as the limited presence of meteorological stations. These two factors considerably increase the uncertainty of a holistic representation of the hydrological processes and a reliable estimation of groundwater recharge. The aim of this research work is to improve the current knowledge on the interaction between surface water and shallow aquifers and to define a method for an integrated modelling of the main components of the water cycle at the catchment scale to be used as input for groundwater modelling. The collection and use of data and methods that allow for the maximum discretisation of the heterogeneity of the elements involved is the guiding thread of this work. The scientific approach is demonstrated for a complex case study, the Valtellina valley (northern Italy), to investigate the interaction among the components of hydrogeologic cycle and their future projections according to climate dynamics. This valley could be considered a perfect case study because it is characterized by an active system that rapidly reacts to meteorological and climatic variations. This is visible by the fluctuation of the groundwater and of the main river, Adda River, during extreme precipitation events and with snow melts during the spring/summer periods. The thesis is divided into three main sections. The first provides a description of hydro-stratigraphy of the Valtellina valley floodplain. This section includes the groundwater flow model in a steady state condition, developed by using FeFlow 7.2, and the relative automatic calibration process for the hydrogeologic parametrization. 5 The second shows the quantification of seasonal groundwater storage volume according to the residual water budget method for two hydrologic years. For the estimation of the main components (Precipitation, Evapotranspiration and Snow water equivalent), new promising satellite-based database and methods are tested. The last one describes the tranFinally, the flow model has been used to evaluate the impact on groundwater of possible climate change scenarios.sient groundwater flow model developed with dynamic boundary conditions obtained from satellite-based methods.
Elbag, Mark A. "Impact of surrounding land uses on surface water quality." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-050306-155834/.
Full textKeywords: Conductivity, pH, Dissolved Oxygen, UV absorbance, Source Water, Surface Water, Dissolved Organic Carbon, Total Organic Carbon, Particle Counts, Turbidity, E. coli, Fecal Coliforms, West Boylston Brook, Wachusett Reservoir, source water protection, surface water protection Includes bibliographical references (p.73-77).
Telci, Ilker Tonguc. "Optimal water quality management in surface water systems and energy recovery in water distribution networks." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45861.
Full textMcCary, John. "Incorporating surficial aquifer ground-water fluxes into surface-water resource management studies." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001095.
Full textRosenberry, Donald O. "Influence of fluvial processes on exchange between ground water and surface water." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3284456.
Full textAnderson, Jacob. "Geochemical Tracers of Surface Water and Ground Water Contamination from Road Salt." Thesis, Boston College, 2013. http://hdl.handle.net/2345/3313.
Full textThe application of road de-icers has lead to increasing solute concentrations in surface and ground water across the northern US, Canada, and northern Europe. In a public water supply well field in southeastern Massachusetts, USA, chloride concentrations in ground water from an unconfined aquifer have steadily risen for the past twenty years. The objectives of this study are to understand spatial and temporal trends in road salt concentrations in order to identify contamination sources and fate. To this end, the methods of this project include field and lab work. Water samples were collected from surface, near-surface, and ground water from March 2012 to March 2013. The other major field data are specific conductance measurements from probes located in three piezometers. In the lab, all samples were analyzed for major ions with ion chromatography analysis. Additionally, trace elements were measured by inductively coupled plasma analysis on a subset of samples. The results of these hydrogeochemical procedures showed several important trends. First, the highest concentrations of sodium and chloride from near-surface samples were located near to roadways. Second, ground water samples taken from glacial sediments contained relatively high concentrations throughout the water column, whereas ground water samples from wetlands had high concentrations only near the surface. Third, there was no clear relationship between pH and cation concentrations. Finally, specific conductance data showed strong seasonal trends near to the surface, whereas values taken from deeper in the aquifer were steadily increasing. Based on these results, it is highly probable that road salt application is the dominate contamination source. The pathways of road salt in the watershed include runoff into surface water and infiltration into the vadose zone and ground water. Road salt appears to preferentially travel through glacial features rather than floodplain features. It is possible that sodium from road salt is sorbed to aquifer sediment and displaces other cations. However, the low values of trace metals suggest that cation exchange is not mobilizing heavy metals. Finally, the increasing specific conductance values deep in the aquifer suggest that road salt is retained within the aquifer and concentrations will likely increase in the future if the current road salt application procedures are continued
Thesis (MS) — Boston College, 2013
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Earth and Environmental Sciences
Mohamed, Ali Sithy Kadija. "Industrial water pollution in a surface water system in Colombo, Sri Lanka." Thesis, Durham University, 1991. http://etheses.dur.ac.uk/1180/.
Full textDiaz-Nieto, Jacqueline. "A GIS water balance approach to support surface water flood risk management." Thesis, University of Sheffield, 2012. http://etheses.whiterose.ac.uk/15005/.
Full textWang, Jialin. "AFM surface force measurements between hydrophobized gold surfaces." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/29031.
Full textPh. D.
DeGenova, John. "Oxidation and Removal of Thin Organic Films From A Wafer Surface: Fundamentals of Ozonated Water Application and Water Recycle." Diss., The University of Arizona, 2001. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_2001_386_sip1_w.pdf&type=application/pdf.
Full textWe acknowledge that the writer has two page 7's in this resource. (List of figures). Includes bibliographical references (leaves 214-218).
Gao, Guangyue. "Some Controllability and Stabilization Problems of Surface Waves on Water with Surface tension." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/64377.
Full textPh. D.
Burner, Joe Gary. "Manganese removal from an organic-laden surface water." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/104297.
Full textAbu, Rumman Malek. "Conjunctive Management of Surface Water and Groundwater Resources." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6917.
Full textGrindstad, Thorvald C., and Runar J. F. Rasmussen. "Deep water ocean surface modelling with ship simulation." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-15492.
Full textNeumann, Natasha Niki. "The ecohydrology of coupled surface water - groundwater systems." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44077.
Full textSmith, Jonathan William Neil. "Pollutant retardation at the groundwater- Surface water interface." Thesis, University of Sheffield, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.500234.
Full textBroadbridge, Simon Glenn. "A biomimetic approach to water-borne surface coatings." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243175.
Full textMcKenna, Sean Patrick. "Free-surface turbulence and air-water gas exchange." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/88474.
Full textIncludes bibliographical references (p. 299-312).
by Sean Patrick McKenna.
Ph.D.
Mallón, Pernia Laura. "Surface-functionalized and hybrid nanocatalysts for water splitting." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/673661.
Full textUna solución para conseguir una fuente de energía libre de carbono es la fotoproducción de H2 mediante la división catalítica del agua (Water splitting, WS, Ecuación 1) utilizando la luz solar. 2H2O + hv --> 2H2 + O2 (Ecuación 1) WS es un proceso en el que el agua se oxida a dioxígeno en el ánodo (reacción de evolución del oxígeno, REO, Ecuación 2), constituyendo así la fuente de electrones para reducir los protones a H2 en el cátodo (reacción de evolución del hidrógeno, REH, Ecuación 3). 2H2O --> O2 + 4H+ + 4e- (Ecuación 2) 2H+ + 2e- --> H2 (Ecuación 3) El desarrollo de catalizadores de WS altamente activos y eficientes es esencial para la correcta cinética de estas dos semireacciones. Las nanopartículas (NPs) son verdaderos catalizadores potenciales debido a su alta estabilidad y relación superficie/volumen, exponiendo altas cantidades de sitios activos. En esta tesis doctoral se han sintetizado diferentes nanoelectrocatalizadores siguiendo el método organometálico, que resulta ventajoso para obtener nanomateriales de superficie limpia. Para entender los factores que afectan a la actividad electrocatalítica de los nanomateriales, se han realizado cálculos teóricos sobre la base de conceptos bien aceptados (energía libre de adsorción de hidrógeno, δGH*, y diagramas de volcán). Dado que los ligandos presentes en la superficie de las NPs metálicas pueden influir en la actividad electrocatalítica, se realizaron cálculos DFT para determinar los modos de coordinación más favorables de diferentes ligandos y obtener los valores de δGH*, obteniéndose correlaciones satisfactorias entre los datos experimentales y los de DFT. Diferentes estudios confirman que los soportes conductores de carbono mejoran la actividad electrocatalítica al restringir la agregación de los nanocatalizadores y mejorar la transferencia de electrones desde el nanocatalizador metálico al electrodo. En esta tesis doctoral se han utilizado dos materiales de carbono, el óxido de grafeno reducido (OGr) y las microfibras de carbono (FC), como soportes de NPs metálicas. Además, se ha estudiado el efecto del dopaje de N y P sobre el OGr en la REH, obteniendo un efecto sinérgico positivo entre heteroátomos y NPs de Ru. A diferencia del grafeno, las microfibras de carbono son más fáciles de manipular y pueden utilizarse directamente como electrodos. Así, se han sintetizado NPs de Ru y Co sobre dos microfibras diferentes, que difieren en la presencia o no de grupos -COOH en la superficie. Además, se han empleado dos metodologías diferentes, in situ y ex situ, para modificar la interfaz entre las NPs y el soporte de carbono mediante la adición de diferentes disolventes (THF o 1-heptanol) o ligandos (4-fenilpiridina, 4PP). Los resultados evidencian que una adecuada interacción entre las NPs y la superficie del soporte es clave para una mejor actividad catalítica, obteniéndose mejores resultados en los sistemas en los que tienen lugar interacciones π-π entre las estructuras Ru-4PP NPs/C o enlaces H entre las NPs de Co(OH)2 y -COOH en la FC. Otra estrategia prometedora es la adición de otro metal a una nanoestructura metálica, lo que conduce a efectos electrónicos beneficiosos al cambiar el entorno químico de los centros metálicos. En este sentido, se sintetizaron sistemas bimetálicos de Ru@Ni-espuma y NPs de RuCo. Se ha estudiado la influencia de diferentes porcentajes de dopaje de Ru en los sistemas de Ru@Ni-espuma sobre la actividad catalítica hacia la REO. Finalmente, se sintetizaron NPs de RuCo utilizando tres ligandos diferentes, 4’-(4-metilfenil)-2,2’:6’,2””-terpiridina, 4-PP y 1-heptanol, con el fin de determinar la influencia del ligando y de la ratio Ru/Co en el tamaño y la morfología de las NPs. Los estudios electrocatalíticos realizados abren una nueva puerta para explorar el interés de los nanocatalizadores bimetálicos en WS y la producción de hidrógeno.
One solution to achieve a carbon free energy source is the photoproduction of H2 by the catalytic water splitting (WS, Eq. 1) using sunlight. 2H2O + hv --> 2H2 + O2 (Eq. 1) WS is a process in which water is oxidized to dioxygen in the anode (oxygen evolution reaction, OER, Eq. 2), thus constituting the source of electrons to reduce protons to H2 in the cathode (hydrogen evolution reaction, HER, Eq. 3). 2H2O --> O2 + 4H+ + 4e- (Eq. 2) 2H+ + 2e- --> H2 (Eq. 3) Developing highly efficient and active WS catalysts is essential for the proper kinetics of these two reactions. Nanoparticles (NPs) are true potential catalysts due to their high stability and surface per volume ratio, exposing high amounts of active sites. In this PhD, different nanoelectrocatalysts have been synthesized by following the organometallic approach which is advantageous for obtaining clean-surface nanomaterials compared to other synthesis methodologies. To understand the factors affecting the electrocatalytic activity of the nanomaterials, theoretical DFT calculations have been performed on the basis of well accepted concepts (hydrogen adsorption free energy, δGH*, and volcano plots). Given that the ligands present on the surface of metal NPs can influence the electrocatalytic activity, DFT calculations were performed to determine the most favorable coordination modes of different ligands and to obtain the δGH* values of the resulting NPs. Successful correlations between experimental and DFT data have been obtained. Conductive C-based supports are known to enhance the electrocatalytic activity by restraining the aggregation of the nanocatalysts and improving the electron transfer from the metal nanocatalyst to the electrode. In this PhD, two different carbon materials, reduced graphene oxide (rGO) and carbon microfibers (CF) have been used as supports for metal NPs. Furthermore, the effect of N and P doping onto rGO has been studied towards the HER, obtaining a positive synergistic effect between the heteroatoms and Ru NPs. In contrast to graphene, CF are easier to handle and can be directly used as electrodes, thus avoiding the issues related to the NPs deposition onto macroscopic electrodes (GC, FTO). Thus, Ru and Co NPs have been synthesized on top of two different CF, differing in the presence or not of –COOH moieties onto the surface. Two different methodologies, in-situ and ex-situ, have been employed in order to tune the interface between the NPs and the C support by adding different solvents (THF or 1-heptanol) for Co NPs or ligands (4-phenylpyridine, 4PP) for Ru NPs. The results evidence that a proper interaction between the NPs and the support surface is key for an improved catalytic activity of the hybrid materials, obtaining better results in the systems where π-π interactions between Ru-4PP NPs/C structures or H-bonds between Co(OH)2 and COOH moieties in the CF take place. Another promising strategy is the addition of another metal onto a metallic nanostructure, leading to beneficial synergistic electronic effects by changing the chemical environment of the metal centers and decreasing the adsorption energy of the reactants. In this sense, bimetallic Ru@Ni-foam and RuCo NPs systems were synthesized. The influence on the catalytic activity towards OER of different percentages of Ru-doping in Ru@Ni-foam systems has been studied. Finally, RuCo bimetallic systems were synthesized by using three different ligands, 4’-(4-methylphenyl)-2,2’:6’,2”-terpyridine, 4-PP and 1-heptanol. The influence of the ligand and the Ru/Co metal ratio on the size and morphology of the NPs has been determined. Preliminary electrocatalytic tests have been performed, opening a new door to explore the interest of bimetallic nanocatalysts for the water-splitting and the production of hydrogen.
Universitat Autònoma de Barcelona. Programa de Doctorat en Química
Li, Xuan. "Fate of Silver Nanoparticles in Surface Water Environments." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1320888780.
Full textAlexandrov, Alexander. "Mathematical modelling of groundwater and surface water interactions." Thesis, Alexandrov, Alexander (2000) Mathematical modelling of groundwater and surface water interactions. PhD thesis, Murdoch University, 2000. https://researchrepository.murdoch.edu.au/id/eprint/51646/.
Full textStiltner, Bridgett, and Phillip R. Scheuerman. "Microbial Enzyme Activity in Surface Water and Sediments." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/2958.
Full textOvcharenko, Roman. "Interaction of Water with the Fe2O3(0001) Surface." Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/19247.
Full textThe present study is a comprehensive systematic theoretical investigation of the water adsorption on the Fe2O3(0001) surface. It covers a broad number of problems inherent to the initial stage of the water adsorption on the transition metal oxide surface: clean surface stability, the influence of surface oxygen defects, the role of the crystallographic and electronic structures on the adsorption configuration, elementary kinetics, the particular qualities of the low and high adsorption coverage regimes and the effect of the hydrogen bonding on adsorption and on the XPS spectra simulation. The low and high coverage regimes from 0.25 up to 1 monolayer water coverage were considered to form a basis for the following increase of water loading mainly observed in experiments. A single adsorption energy picture was expanded to take into account the water vapour environment through the Gibbs free energy. The statistical ensemble was employed to classify and interpret the averaged values of the adsorption configurations set rather than the ``invisible'' in experiment quantities intrinsic to the particular single adsorption configuration. In order to make the statistical analysis feasible an effective distance matrix scheme was developed. It helped to reduce the total number of structures to consider without loss of generality by virtue of the surface space symmetry. Based on the statistical contribution of each individual adsorption configuration, the O-1s XPS was simulated for the various water vapour environments. A good agreement between the simulated and experimental spectra was found. Wherever it was important, the similarities and differences between water adsorption on the Fe2O3, Al2O3 and Fe3O4 surfaces were stressed and the main tendencies were deduced. Based on the present study, the whole picture of the initial stage of the Fe2O3(0001) surface wetting process was established.
Wang, Xiaolu. "Janus Colloids Surfing at the Surface of Water." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS272/document.
Full textAt the single-particle level, the main difference between active colloids and passive ones is the time scale over which the motion crosses over from ballistic to diffusive regime. In both cases, friction coefficients or equivalently diffusion coefficients determine this time scale. For instance, the motion of a passive colloid of 1m radius is diffusive when observed over lag times longer than a microsecond, once the direction of its momentum has been randomized by collisions with solvent molecules. At the macroscopic scale these collisions are accounted for by the translational friction coefficient. For an active colloid the effective diffusive behavior observed over lag times larger than few seconds results from the randomization of the direction of self-propulsion by rotational diffusion. In this thesis we investigated the motion of an active Janus colloid trapped at air-water interface. Spherical catalytic Janus colloids have been prepared through the deposition of platinum metal at the surface of silica particles. Immersion depth of the Janus colloid as well as their orientation with respect to the water surface, has been characterized and interpreted in terms of the non-uniform wetting properties of the Janus particles. The motion of the active Janus colloids in the presence of various concentration of hydrogen peroxide H2O2 as fuel was characterized by video microscopy and the trajectories analyzed through the mean square displacement and the velocity autocorrelation function. The types of trajectories, directional and circular ones that we observed in our experiments, revealed the effective force and torque induced by the catalytic decomposition of H2O2. At the water surface, active colloids perform more persistent directional motions as compared to the motions performed in the bulk. This has been interpreted as due to the loss of degrees of freedom resulting from the confinement at interface and also to the partial wetting conditions that possibly bring new contributions to the rotational friction at interface
Oqielat, Moa'ath Nasser. "Modelling water droplet movement on a leaf surface." Thesis, Queensland University of Technology, 2009. https://eprints.qut.edu.au/30232/1/Moa%27ath_Oqielat_Thesis.pdf.
Full textOqielat, Moa'ath Nasser. "Modelling water droplet movement on a leaf surface." Queensland University of Technology, 2009. http://eprints.qut.edu.au/30232/.
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