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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.
541

Implementing Municipal Water Conservation Policy: Goals, Practices and the Case of Texas

Sokulsky, Kariann Elizabeth 05 1900 (has links)
This study examines whether water conservation is actually being incorporated into municipal water management practices. The development of a conservation policy from a general goal declaration to specific programmatic practices is reviewed for a Texas state water agency, the Texas Water Development Board. From January 1986 through September 1989, 102 political units in Texas applied to the Board for water-related loan funds and thus were required to implement municipal water conservation plans. Two aspects of this conversation policy are assessed: one, the Board's procedural arrangements for the development and review of water conservation plans, and two, the conservation plans of each political unit. It is concluded that Texas state water managers, and local manager also, have yet to incorporate conservation as a significant planning tool for the achievement of water management goals.
542

Time series analysis of water quality data

Bhargava, Navin K January 2010 (has links)
Digitized by Kansas Correctional Industries
543

A comparative study of health of rednose labeo baded on the quantitative health assessment index, bioaccumulation and histopathology in the Olifants Rive

Lebepe, Jeffrey January 2012 (has links)
Thesis (M. Sc. (Zoology)) -- University of Limpopo, 2012 / The Olifants River System is one of the most polluted river systems in Southern Africa. The Olifants River catchment is characterized by large-scale mining, power generation, heavy industry and inadequate domestic sewage treatment. Fish and crocodile kills have become commonplace over the past decade, especially in the upper catchment and Kruger National Park. The present study was carried out at Loskop and Flag Boshielo dams, two major impoundments in the Olifants River. Water and sediment samples were collected at each dam during winter (July 2011) and summer (November 2011), frozen and sent to an accredited water lab for chemical analysis. Atleast fifteen fish specimens from each dam were collected during each survey using gill nets. To evaluate the health of red-nose labeo, (Labeo rosae) in the two dams, fish organs were assessed macroscopically using the fish Health Assessment Index (HAI) protocol and a section of liver tissue and gills were dissected out, frozen and sent to an accredited water lab for metal analysis. The remainder liver samples were fixed in 10% buffered formalin and sent to University of Pretoria Pathology Laboratory for histopathological analysis. The concentration of nutrients and ions were higher at Loskop Dam whereas most metal concentrations were found to be higher at Flag Boshielo Dam. The present study categorised Flag Boshielo Dam as oligotrophic with Loskop Dam being mesotrophic. The concentration of aluminium, copper, antimony, iron, lead, selenium and strontium was higher at Flag Boshielo Dam with manganese, silica and zinc being higher at Loskop Dam. Although the concentrations of these toxic constituents varied, there were no significant differences between localities (p>0.05). The constituents that showed high concentrations in sediment were iron and aluminium. The general trend of accumulation in sediment was as follows: Fe > Al > Si > Mn > Zn > Cu > Sb > Sr > Pb > Se at Loskop Dam whereas at Flag Boshielo Dam was as follows: Fe > Al > Mn > Si > Zn > Cu > Sr > Pb > Sb > Se. The liver generally accumulated higher concentrations of metals than the other tissue. General trend of liver > gills > muscle was reported for Al, Cu, Fe, Pb, Sb, Se, Si and Zn with gills > liver > muscle trend being reported for Mn and Sr at both localities. Macroscopic abnormalities were observed for some gills and liver at both localities. Parasite (Lernaea cyprinacea) induced lesions on the skin and mild erosion on the tail fin of some fish were recorded at Flag Boshielo Dam. Most of the histopathological alterations were common at both localities but hydropic glycogen and hyaline droplets were observed only at Loskop Dam, with haemosiderin being observed at Flag Boshielo Dam. Both quantitative HAI results and histopathology have shown that the fish population from Flag Boshielo Dam are in better condition/health than the population Abstract Abstract Page iv from Loskop Dam. There might be a correlation between the nutrient levels and fish health. The overall ecological state is better at Flag Boshielo Dam than Loskop Dam.
544

Planning for sustainable urban water: systems-approaches and distributed strategies.

Fane, Simon Anthony January 2005 (has links)
This thesis develops and applies a number of methods for systems analysis and assessment within the field of sustainable urban water. These focus on the evaluation of distributed strategies. In line with arguments made within the thesis, the methods developed assess urban water on a whole-system basis, with the system defined in terms of the services provided. Further, the thesis argues for sustainable urban water planning to take a pluralist stance; both in the conception of sustainable urban water and the strategies considered. The challenges of sustainability and sustainable development are fundamentally problems of complex systems. Planning and assessment of sustainable urban water therefore require a systems-approach. Systems-thinking is not, however, a unified body of knowledge and this thesis develops a unique perspective on systems-thinking which is used to critically review the fields of sustainable urban water and its assessment. Within these reviews, the thesis develops a framework for understanding sustainable urban water in terms of a number of varied approaches, and describes a feasible theoretical basis for assessing sustainable urban water. Many, so called, sustainable strategies are small-scale and distributed in nature. Distributed strategies include decentralised systems, embedded technologies, and local measures for conservation. Traditional systems analysis methods have failed to account for distributed strategies. To adequately include distributed strategies, this thesis argues that assessment methods will need to be based on whole-system modelling, utilise end-use models of service provision, and include - in the form of a demand forecast - a time dimension in relation to service provision. This thesis proposes new methods for microbial risk assessment on a whole-system basis and Least cost planning for (urban water) Sustainable Scenarios (LeSS). A novel evaluation framework for least cost planning for water supply, which provides an equivalent comparison of demand- and supply-side options, is also developed. These methods are illustrated through case studies. These case studies illustrate the potential of distributed strategies. When assessed on an equivalent basis, in various examples, distributed strategies are shown to be particularly cost effective. Decentralised wastewater reuse systems are also shown to impose a theoretically lower level of pathogen risk on the community than equivalent centralised reuse schemes. Despite the advances in assessment methodologies made within the thesis, further development of practical tools for assessing and planning sustainable urban water remains an urgent goal.
545

Kinetic modelling studies of As(III) oxidation in dark pH 3 and 8 Fenton - mediated and pH 8 Cu(II) - H2O2 systems

Botfield, Andrew, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2006 (has links)
In this thesis, a combination of laboratory experimentation under well defined conditions coupled with a kinetic modelling approach is used to verify the existence and respective kinetic rates of previously unconfirmed or postulated mechanisms that drive and limit dark Fenton (Fe(II)/H2O2) - mediated As(III) oxidation at pH 3 and 8 and dark Cu(II) - H2O2 - mediated As(III) oxidation at pH 8. Dark Fenton - mediated oxidation of As(III) at pH 3 is first examined and the effects of the variation in the concentration of reactants (As(III), Fe(II) and H2O2), oxygen, phosphate and organics (2 - propanol, formate, and citrate) are reported and analysed. The kinetic models developed for these systems show high applicability to full scale water treatment application and key mechanistic findings include the significance of the cycling of Fe(II) / Fe(III) via HO2 ???/O2 ??????, the effects of As(IV) termination reactions in the absence of oxygen and the retarding effects of phosphate due to the postulated formation of a Fe(III) - phosphate complex (at a derived rate constant of 2.2 x 106 M-1s-1, that also appears to have negligible kinetic activity in terms of reduction to Fe(II) by HO2 ???/O2 ??????). The work also demonstrates the significance of the free radical by products of formate and citrate oxidation by ???OH (HCOO???/CO2 ?????? and 3HGA???2???). The examination of the dark Cu(II) - H2O2 - mediated oxidation of As(III) at pH 8 with variation in the concentration of reactants (As(III), Fe(II) and H2O2), carbonate and organics (2 - propanol, formate and citrate) demonstrated for the first time the high applicability of this system to the pre - oxidation of As(III) in water treatment and mechanistically that ???OH and CO3 ?????? are the dominant As(III) oxidants in this system. The As(III) oxidant CO3 ??????, is suggested to be generated by the interaction of ???OH and O2 ?????? with the carbonate matrix, at the respective rate constants of 4.9 x 107 M-1s-1 and 5.5 x 106 M-1s-1. Examination of the dark Fenton - mediated oxidation of As(III) at pH 8 and the effects of variation in the concentration of reactants (As(III), Fe(II) and H2O2), carbonate, organics (2 - propanol, formate and citrate) and Cu(II) demonstrates the varied potential mechanistic pathways in relation to the generation of As(III) oxidants from the Fenton reaction, Fe(II) + H2O2 such as Fe(IV) and CO3 ?????? and the previously dismissed ???OH, due to the presence of Fe(II) - citrate complexes. This work also demonstrates and models the enhancement of As(III) oxidation in the presence of an additional transitional metal ion, Cu(II).
546

Planning for sustainable urban water: systems-approaches and distributed strategies.

Fane, Simon. January 2005 (has links)
This thesis develops and applies a number of methods for systems analysis and assessment within the field of sustainable urban water. These focus on the evaluation of distributed strategies. In line with arguments made within the thesis, the methods developed assess urban water on a whole-system basis, with the system defined in terms of the services provided. Further, the thesis argues for sustainable urban water planning to take a pluralist stance; both in the conception of sustainable urban water and the strategies considered. The challenges of sustainability and sustainable development are fundamentally problems of complex systems. Planning and assessment of sustainable urban water therefore require a systems-approach. Systems-thinking is not, however, a unified body of knowledge and this thesis develops a unique perspective on systems-thinking which is used to critically review the fields of sustainable urban water and its assessment. Within these reviews, the thesis develops a framework for understanding sustainable urban water in terms of a number of varied approaches, and describes a feasible theoretical basis for assessing sustainable urban water. Many, so called, sustainable strategies are small-scale and distributed in nature. Distributed strategies include decentralised systems, embedded technologies, and local measures for conservation. Traditional systems analysis methods have failed to account for distributed strategies. To adequately include distributed strategies, this thesis argues that assessment methods will need to be based on whole-system modelling, utilise end-use models of service provision, and include - in the form of a demand forecast - a time dimension in relation to service provision. This thesis proposes new methods for microbial risk assessment on a whole-system basis and Least cost planning for (urban water) Sustainable Scenarios (LeSS). A novel evaluation framework for least cost planning for water supply, which provides an equivalent comparison of demand- and supply-side options, is also developed. These methods are illustrated through case studies. These case studies illustrate the potential of distributed strategies. When assessed on an equivalent basis, in various examples, distributed strategies are shown to be particularly cost effective. Decentralised wastewater reuse systems are also shown to impose a theoretically lower level of pathogen risk on the community than equivalent centralised reuse schemes. Despite the advances in assessment methodologies made within the thesis, further development of practical tools for assessing and planning sustainable urban water remains an urgent goal.
547

The effects of using a cation exchange water softener on blood pressure

Kang, Ki Sung 29 August 1990 (has links)
Water in 70 percent of the cities in the United States is hard enough that softening is either required or recommended. It is estimated that approximately 30 percent of all homes in the United States use water softeners. Water softeners, the cation exchange types suited for residential use, exchange sodium for the calcium and magnesium in water. The increase in sodium levels in the softened water caused by cation exchange softening is a direct function of the hardness level of the untreated water. For people who use groundwater, which has a relatively high level of naturally occurring sodium, magnesium and calcium, the additional sodium from cation exchange water softeners may create health hazards for the general population and could adversely affect those who are sensitive to salt or on low sodium diets. To prevent potential health hazards for the general population, no consumption of softened water by cation exchange water softeners should be recommended. If soft water is needed for some practical reasons, a "Separate Water Line System" should be recommended for homeowners. / Graduation date: 1991
548

Hållbart nyttjande av vattenresurser på Gotland : vision och verklighet

Holén, Elinor January 2011 (has links)
Fresh water has become more and more of a scarce commodity. Water scarcity isn't first and foremost a cause of drought and wasting, but a cause of inequality and mismanagement. This is not only a problem for developing countries, and there can also be variations within countries. The municipality of Gotland has a development program called Vision Gotland 2025, with goals for growth and sustainable development. The aim of this study is to examine whether the use and management of water resources on Gotland and Vision Gotland 2025 is conformed to the Water Framework Directive and the Ecosystem Approach in terms of sustainability. Focus is on the quantitative aspects of water supply. The study has mainly been done by studying publications from the authorities concerned. Although annual precipitation in general is enough to provide fresh water for the population, water shortage occurs in some areas during the summers. Three of the four main catchment areas on Gotland have unsatisfactory quantitative status, and is likely to have so also when the time limit of the next evaluation is due in 2015. Since both the population and tourism is presumed to increase, according to Vision Gotland 2025, the conclusion drawn is that the use of water resources is not sustainable, even though the management per se does conform to the ecosystem approach.
549

Development of a complementary chemiluminescence/HPLC method for predicting the chemical fate of 1-Bromo-3-Chloro-5,5-Dimethylhydantoin under aqueous conditions /

Jones, Jennifer Ruth Miller. January 2003 (has links)
Thesis (M.S.)--University of North Carolina at Wilmington, 2003. / Includes bibliographical references (leaves : [65]-67).
550

Water Conservation for Domestic Users: With Special Reference to Warm Desert Climates

DeCook, K. James, Haney, Richard A., Stone, Mary Ann, Doran, Thomas E., Fangmeier, D. D., Fazio, Steve, Frobel, Ronald K., Halderman, Allan, Johnson, Gordon, Jones, Warren, Kneebone, William, Matlock, W. G., Phillips, Robert A., Sacamano, Charles, Welchert, W. T., Brooks, Frank, Brice, Robert, Graffius, Paul January 1977 (has links)
A Handbook Prepared by The University of Arizona for the City of Tucson.

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