Buoyant plumes in cold fresh water are of interest because of the possibility of buoyancy reversal due to the nonlinear relation between temperature and density in water. Thus an initially rising plume may become a fountain. This project aims to mathematically model such plumes and fountains using numerical simulation by the means of a commercial software, Comsol Multiphysics. Both turbulent and lam- inar cases were investigated in different geometries, and with the assumption that density is a quadratic function of temperature. The turbulent flow cases as con- sidered here in this thesis are relevant to practical applications such as industrial discharge in cold lakes: whereas, the laminar flow case relates to laboratory experi- ments which are typically at scales too small for the flow to be turbulent. Previous investigation on warm discharge placed more attention on the biological implications of the spread along the lake bed, and not interested in analysing the dynamics of such flow, which turns out to be our focus. Furthermore, investigations on buoyant plumes that become negatively buoyant at later time (fountain flow) as considered previously, are based on the assumption that density is a linear function of tem- perature: where entrainment always reduces buoyancy. Whereas, the consideration of the temperature of maximum density is crucial and realistic in many practical situations, especially the power station warm discharge. Mixing is then bound to produce a mixture that is denser than both the discharge and the ambient water if receiving water is less than Tm: where this situation differs from plumes with linear mixing properties. Therefore, our focus is to better fathom the behaviour of warm discharge so as to give a detailed description of the flow, and also to observe buoyancy reversal whenever water that is denser than both the discharge and the receiving water is produced. The simulations were carried out for Prandtl number Pr = 7 & 11.4 and over the ranges of Froude number 0.1 ≤ Fr ≤ 5 and Reynolds numbers 50 ≤ Re ≤ 106, with source temperatures that are assumed to be higher than the temperature of maximum density Tm, and the ambient water below the Tm. Our results show some distinct behaviours from those experimental investigations by Bukreev, who also considered warm discharge where water that has temperature above the temperature Tm is initiated into a medium below Tm. The results here also showed some differences from those investigations with the linear dependence relation assumption.

This study aims to investigate the stable isotopic characteristics of meteoric and ground waters, and to obtain spring flow rates in the Coronet Peak Skifield, Queenstown. Spring flows were gathered during the winters of 2008 and 2009, whilst water samples were collected from precipitation, springs, reservoirs and groundwater during July, August and September 2009. The spring flows were examined and the water samples were analysed for δD and δ¹⁸O values using the CF-IRMS at the University of Canterbury. A database has been gathered from all natural water sources to give a local meteoric water line (LMWL) for the area that fits clearly with the global meteoric water line. The LMWL has an R2 value of 0.97 and the equation is δD = 8 δ¹⁸O +10. An understanding of evaporation as it occurs in the water storage reservoirs of the mountain has also been obtained, giving rise to a local evaporation line. The stable isotope ratios of hydrogen and oxygen within precipitation have been used extensively to characterise the hydrogeology with emphasis on altitude effects, storm duration and variations in storm track trajectories. Of these three phenomena, it is the trajectory of the storm track that is best shown to affect the composition of precipitation in this area. The air masses advancing on the study area from the north being more depleted in their isotopic signatures, with approximate δD and δ¹⁸O values of –130‰ and -16‰. The air masses approaching from a southerly direction are more positive in comparison, having approximate δD and δ¹⁸O values of –65‰ and -9‰. The altitude effect in precipitation on the Skifield has led to an altitude gradient being found: for every 100-metre increase in elevation, δ¹⁸O decreases by 0.71‰. However there were some inconsistencies. The influence on precipitation from storm duration is also inconsistent in this area. The R2 values range from 0.14 to 0.99, but this method does not take into account the position of the individual samples. Some samples did not plot in the expected order that is governed by a decrease in stable isotopic ratios with storm duration. The stable isotopic compositions within meteoric waters can be used as tracers of water sources. The isotope date of the springs also infers an altitude effect. The springs gave an altitude gradient of a decrease –0.43‰ with each 100-metre increase in elevation. This indicates that precipitation is the main influence on the stable isotopic composition of the springs in this area. However, data shows differences between the current precipitation and the groundwater compositions, indicating that present precipitation is not flowing from the springs, past precipitation is. The stable isotopic compositions of the springs have also been correlated with groundwater isotope data and suggest the sources of the springs are groundwater dominated. Although some springs compositions indicate an influence by current precipitation. This is shown by a negative stable isotopic trend in the precipitation sampled in August, corresponding with a relatively negative stable isotopic composition in some springs during this time period. Monitoring of spring flows on Coronet Peak have led to an average winter flow rate being established of 26.5 litres per second. Spring flow rates range from 0.25 – 6 litres per second. This monitoring has indicated the springs of the greatest yield that are not already being utilised on the Skifield. It is these springs that should be further investigated as to whether they would provide a sustainable source of water on the mountain. This locally derived water would then be utilised for the purposes of artificial snowmaking and other activities and amenities that are currently operated by NZ Ski on Coronet Peak.

Made available in DSpace on 2014-06-11T19:32:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-26Bitstream added on 2014-06-13T20:24:18Z : No. of bitstreams: 1 oliveira_ac_dr_jabo.pdf: 650394 bytes, checksum: 3022a3790349efbed366f6fa0374267e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foram estudadas 180 amostras de água de 45 consultórios odontológicos da cidade de Barretos-SP, com o objetivo de isolar, identificar, determinar a contagem de isolados de Pseudomonas aeruginosa UFC/mL, determinar o perfil clonal e avaliar a diversidade genômica dos isolados e a suscetibilidade das mesmas frente a diferentes antibióticos. As amostras de água foram filtradas em filtro Millipore® e a membrana colocada sobre o centro de uma placa de Petri contendo agar cetrimida, As colônias típicas de bactérias do gênero Pseudomonas foram identificadas pelo método de Gram, inoculação em TSI agar (Triple Sugar Iron), crescimento a 42ºC, produção de pigmento, produção de alginato, oxidase, motilidade e alcalinização da acetamida. O teste utilizado para análise genômica foi o ERIC-PCR. Dos 76 (42,2%) isolados de Pseudomonas aeruginosa, 15 eram provenientes das amostras de torneira de lavagem das mãos, 18 de reservatório de garrafa pet, 23 de seringa tríplice e 20 do motor de alta rotação. Todos os isolados de Pseudomonas aeruginosa foram submetidos ao teste de suscetibilidade segundo a técnica de Kirby- Bauer. Dos antibióticos testados o que apresentou melhor resultado quanto à sensibilidade (65,8%) foi a ciprofloxacina. Quanto à similaridade genética dos isolados dos diferentes pontos analisados, foram encontrados nove “clusters” de 100% de similaridade. / The biofilm found in water supplies and lines of hospitals and dental units is extremely important because it presents a large number of bacteria, leading to risk of infection in immunocompromised patients vulnerable to opportunistic pathogens such as the Pseudomonas aeruginosa. One hundred eighty water samples from dental units of the city of Barretos-SP were evaluated. The water samples filtered in Millipore® filter were incubated in plates containing Cetrimide ágar. The bacteria colonies were identified through the gram-staining test, inoculation in agar T.S.I (triple sugar Iron), growth at 42 ° C, pigment production, production of alginate, oxidase acetamide alkalization and motility observation. All Pseudomonas aeruginosa bacteria were submitted to the susceptibility test according to the Kirby-Bauer technique. The test used for genomic analysis was the ERIC-PCR. From the total microorganisms studied, 76 (42,2%) were positive for Pseudomonas aeruginosa, isolates from 180 water samples, where 15 strains were from hand washing incoming local water supplies, 18 from PET bottled water, 23 from 3-in-1 syringes and 20 from the high speed handpiece. In relation to the antibiotics tested, the one presenting the best result with regard to sensibility was ciprofloxacin with 65.8%. The genetic similarity of isolates from different points analyzed, there were nine clusters of 100% similarity.

Orientador: Fernando Antônio de Ávila / Banca: José Moacir Marim / Banca: Patricia Amoroso / Banca: Simone Barone Salgado Marques / Banca: Tammy Priscilla Chioda Delfino / Resumo: Foram estudadas 180 amostras de água de 45 consultórios odontológicos da cidade de Barretos-SP, com o objetivo de isolar, identificar, determinar a contagem de isolados de Pseudomonas aeruginosa UFC/mL, determinar o perfil clonal e avaliar a diversidade genômica dos isolados e a suscetibilidade das mesmas frente a diferentes antibióticos. As amostras de água foram filtradas em filtro Millipore® e a membrana colocada sobre o centro de uma placa de Petri contendo agar cetrimida, As colônias típicas de bactérias do gênero Pseudomonas foram identificadas pelo método de Gram, inoculação em TSI agar (Triple Sugar Iron), crescimento a 42ºC, produção de pigmento, produção de alginato, oxidase, motilidade e alcalinização da acetamida. O teste utilizado para análise genômica foi o ERIC-PCR. Dos 76 (42,2%) isolados de Pseudomonas aeruginosa, 15 eram provenientes das amostras de torneira de lavagem das mãos, 18 de reservatório de garrafa pet, 23 de seringa tríplice e 20 do motor de alta rotação. Todos os isolados de Pseudomonas aeruginosa foram submetidos ao teste de suscetibilidade segundo a técnica de Kirby- Bauer. Dos antibióticos testados o que apresentou melhor resultado quanto à sensibilidade (65,8%) foi a ciprofloxacina. Quanto à similaridade genética dos isolados dos diferentes pontos analisados, foram encontrados nove "clusters" de 100% de similaridade. / Abstract: The biofilm found in water supplies and lines of hospitals and dental units is extremely important because it presents a large number of bacteria, leading to risk of infection in immunocompromised patients vulnerable to opportunistic pathogens such as the Pseudomonas aeruginosa. One hundred eighty water samples from dental units of the city of Barretos-SP were evaluated. The water samples filtered in Millipore® filter were incubated in plates containing Cetrimide ágar. The bacteria colonies were identified through the gram-staining test, inoculation in agar T.S.I (triple sugar Iron), growth at 42 ° C, pigment production, production of alginate, oxidase acetamide alkalization and motility observation. All Pseudomonas aeruginosa bacteria were submitted to the susceptibility test according to the Kirby-Bauer technique. The test used for genomic analysis was the ERIC-PCR. From the total microorganisms studied, 76 (42,2%) were positive for Pseudomonas aeruginosa, isolates from 180 water samples, where 15 strains were from hand washing incoming local water supplies, 18 from PET bottled water, 23 from 3-in-1 syringes and 20 from the high speed handpiece. In relation to the antibiotics tested, the one presenting the best result with regard to sensibility was ciprofloxacin with 65.8%. The genetic similarity of isolates from different points analyzed, there were nine clusters of 100% similarity. / Doutor

There are four distinguishable groundwater systems in the Boise area, Idaho, U.S.A., identified as modern batholith, thermal batholith, Boise frontal fault, and Nampa-Caldwell systems (Figure 1). Modern batholith and thermal batholith groundwaters are located in Tertiary to Cretaceous aged granites and granodiorites of the Atlanta lobe of the Idaho Batholith. The frontal fault system near Boise, ID defines the southeastern edge of the Idaho Batholith, and divides the batholith from the western Snake River Plain. The Nampa-Caldwell system is in the volcanic, fluvial and pluvial sediments of the western Snake River Plain. Groundwater ages for these systems are modern, 5-15 ka, 10-20 ka, and 20-40 ka respectively. Local meteoric water lines (LMWL) using the delta 2H and delta 18O composition of the groundwater were defined for each system using linear regression techniques. LMWL had variable and defined single slopes of 6.94 and 8. Deuterium excess values (d) were found for each system for each linear regression method. Relative differences of the deuterium excess value assuming the two single slope methods were similar. Changes in moisture source humidity and temperature, and Boise area recharge temperatures calculated from stable isotopic data and the deuterium excess factor agree with other published data. At the moisture source there was a 9% humidity increase and a 7-6 °C decrease of sea surface temperature between the present and the last glacial maximum (LGM). The local temperature decreased 4-5 °C from the present to the LGM for the Boise area.

The Reconstruction of the Central Wastewater Treatment Plant in Prague constitutes a fundamental challenge for the Czech capital city of Prague. The existing wastewater treatment plant is obsolete and fails to comply with limits set forth by the Council Directive 91/271/EEC concerning urban waste-water treatment. Thus, it is necessary to build a new waterline and reconstruct the old one. As such a project would be financially demanding, its implementation is dependent upon a subsidy from the EU Operational Programme "Environment". There are also more variants of the reconstruction of the Central Wastewater Treatment Plant in Prague. In the thesis, the author compares the contemplated options of re-building and reconstruction of the Central Wastewater Treatment Plant in Prague. He also examines the influence of negotiations with European Commission representatives and of the amount of the subsidy upon the choice of the final option. A hypothesis of the study is that due to the subsidy policy creates pressure on the final form of the reconstruction of the Prague Central Wastewater Treatment Plant, which directly interact its economic efficiency.

The Master‘s thesis addresses sanitation installation and gas installation in the indoor swimming pool in Litomyšl. The theoretical part focuses on the use of greywater and rainwater as service water. The thesis includes the design of several variants with their assessment. The project for construction is also part ofthe thesis.

PhDENV / Department of Hydrology and Water Resources / Geothermal springs are natural geological phenomena that occur throughout the world. South Africa is endowed with several springs of this nature. Thirty-one percent of all geothermal springs in the country are found in Limpopo province. The springs are classified according to the residing mountain: Soutpansberg, Waterberg and Drakensberg. This study focused on the geothermal springs within the Soutpansberg region; that is, Mphephu, Siloam, Sagole and Tshipise. The study was aimed at elucidating on the isotopic signatures and trace metals concentrations from the geothermal springs to their environmental media in Soutpansberg region. This study also assessed the interconnectivity of the isotopic signatures within the ecosystem and evaluated the potential human health risks associated with trace metals from geothermal springs and surrounding soils in the study areas. Geothermal springs and boreholes were sampled for a period of twelve months (May 2016 – May, 2017) to accommodate two major seasons in the study areas. The surrounding soils were sampled vertically from a depth of 10 cm to 50 cm for trace metals and isotopic compositions. Three different plants were sampled at each of the study sites, namely, Amarula tree, Guava tree and Mango tree at Siloam; Acacia tree, Fig tree and Amarula tree at Mphephu; Amarula tree, Lowveld mangosteen and Leadwood tree at Sagole; Sausage tree, Amarula tree and Acacia tree at Tshipise. To achieve the objectives, the physicochemical, geochemical and isotopic compositions of the geothermal springs, boreholes, soils and vegetation were analysed using ion chromatography (IC) (Dionex Model DX 500), inductively coupled plasma-mass spectrometer (ICP-MS), HTP-Elemental analyzer, Liquid water isotope analyzer (LWIA-45-EP) and Liquid scintillation analyzer. The temperature, electrical conductivity (EC), pH and total dissolved solid (TDS) of the geothermal springs and boreholes samples were measeured in situ and in the laboratory. Trace metals analysed in geothermal springs, boreholes, soil and vegetation include Beryllium (Be), Chromium (Cr), Manganese (Mn), Cobalt (Co), Nickel (Ni), Copper (Cu), Arsenic (As), Selenium (Se), Cadmium (Cd), Antimony (Sb), Barium (Ba), Vanadium (V), Zinc (Zn), and Mercury (Hg). vii | Isotopic signatures and trace metals in geothermal springs and their environmental media within Soutpansberg Results obtained from this study in the studied geothermal springs and boreholes were classified according to their temperature as hot and scalding; except for tepid boreholes. This study has provided comprehensive physicochemical, geochemical and isotopic compositions of the geothermal springs within the Soutpansberg region (Siloam, Mphephu, Sagole and Tshipise). The local meteoric line (δD = 7.56δ18O + 10.64) was generated from rainwater in Vhembe district. This is a crucial component for depicting the source and flow path of the geothermal springs/boreholes; and could be used for future isotopic hydrological studies within the locality. Rain formation processes within Soutpansberg occurred under isotopic equilibrium conditions with minor evaporation effect during rainfall. The δD and δ18O values of the geothermal spring water/boreholes confirm that the waters are of meteoric origin, which implies that rainfall is the fundamental component of these groundwaters because they were derived from the infiltration of rainwater, with significant contribution of another type of water in the deeper part of the aquifer. Na-Cl and Na-HCO3 were established as the water types, which are typical of marine and deep groundwaters which are influenced by the ion - exchange process. The reservoir/aquifer temperature of these springs ranges between 95 – 185°C (Na-K geothermometer), which implies most of the waters are mature water (not native). Hence, geothermal springs water is a mixture of the rainwater and salt water. Radiocarbon values of the geothermal springs ranged from 2700 to 7350 BP, this implies that they are submodern and a mixture of submodern and modern waters. Tritium relative age also corroborates with radiocarbon age, that is the groundwaters were recharged before and after 1952. This gives an indication that the rainfall contributes to the geothermal springs recharge. Various radiocarbon correction models were employed and constrained by tritium relative age. Ingerson and Pearson, Eichinger and Fontes and Garnier correction models have been shown to be the most appropriate models for radiocarbon correction of groundwater in this semi-arid region. Although, geothermal springs water and boreholes are not fit for drinking due to high fluoride content, they could be used for the following: domestic uses (drinking exclusive) due to its softness, direct heating in refrigeration, green-housing, spa, therapeutic uses, aquaculture, sericulture, concrete curing, coal washing and power generation. In contrast with mentioned uses, viii | Isotopic signatures and trace metals in geothermal springs and their environmental media within Soutpansberg the studied geothermal springs are currently used for domestic purposes (drinking inclusive), limited irrigation and spa (swimming and relaxation). This is an eco-hydrological study that shows the interconnectivity of isotopic signatures among water (rainwater, geothermal springs and boreholes), soils and vegetation. The soil-water reflects the rainwater/geothermal springs water in isotopic composition, which is more depleted as a result of isotopic fractionation in soil. δD values of soil-water increase, whereas δ13C values in soil-water decrease with the soil depth at all sites. Two equations connecting δD and δ13C in soil-water were deduced per season for soil-water; δ13C = 0.0812δD - 10.657 in winter; δ13C = -0.0278δD - 21.945 for summer. δ13C in soil-water is induced by Crassulacean Acid Metabolism (CAM) (mixture of C3 and C4 photosynthetic cycles) with a stronger C4 trend, which corroborates with δ13C of the geothermal springs. From literature, Amarula and Acacia trees have been documented for isotopic compositions, while this study has given additional information on other plants including Lowveld, Leadwood, Sausage, Fig, Guava and Mango trees. These plants are categorised as C3, C4 and CAM plants. C3 plants include Amarula, Lowveld and Leadwood trees; C4 plants include Acacia and Sausage trees; and CAM plants include Fig, Guava and Mango trees. This study shows that with CAM soils, there is a possibility of having either C3, C4 or CAM vegetation. This finding has shown that the δD and δ13C isotopes in water, soil and vegetation are interrelated, which has been statistically justified. This study has shown the potential human health risks associated with trace metals concentrations from geothermal springs and their surrounding soils. From the geothermal spring’s water, it was found that As, Cr and Cd were the highest contributors to the cancer risk with children having a higher risk than adults. Whereas in soils, it was found that Cr, As and Co were the highest contributors to the cancer risk in the studied communities. Therefore, the cancer risk is high in the general population; that is 1 in 72-162 individuals in children and 1 in 7-107 individuals for adults. The ingestion route seems to be the major contributor to excess lifetime cancer risk followed by the dermal pathway. Therefore, proper monitoring and control measures to protect human health, particularly in children, should be implemented for safety. The study also explored the use of surrounding trees ix | Isotopic signatures and trace metals in geothermal springs and their environmental media within Soutpansberg for phytoremediation and found their uptake capacity to be high, thus, they could be used as bio-indicators to assess the level of contamination of trace metals in the soil. In conclusion, this study has eludicated on the isotopic signatures and trace metals concentrations from the geothermal springs and their surrounding soils and vegetation within Soutpansberg. This study has contributed towards the advancement and enhancement of the existing knowledge of the geothermal systems, such that water resource management could be applied successfully in the respective areas with similar characteristics for the benefit of the local communities and society at large. Hence, this study recommends that proper monitoring and control measures need to be put in place to protect human health, especially in children. / NRF