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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.
11

Détection moléculaire du parasite Cryptosporidium dans des échantillons d'eau

Fontaine, Mélanie Miegeville, Michel. Moisan, Jean-Paul January 2003 (has links) (PDF)
Thèse doctorat : Médecine. Parasitologie : Université de Nantes : 2003. / Bibliogr. f. 197-217.
12

Stratégies hydrauliques pour améliorer la qualité de l'eau potable en réseau de distribution

Simard, Andréanne. January 1900 (has links) (PDF)
Thèse (M.Sc.)--Université Laval, 2008. / Titre de l'écran-titre (visionné le 12 janvier 2009). Bibliogr.
13

Drinking water perception : the influence of water quality and consumer location in the distribution system = Perception de l'eau du robinet : l'influence de la qualité de l'eau et de la localisation des consommateurs dans le réseau de distribution /

Turgeon, Steve. January 2002 (has links)
Thèse (de maîtrise)--Université Laval, 2002. / Bibliogr.: f. 44-47. Publié aussi en version électronique.
14

De l'Alimentation d'une ville en eau potable.

Marais, Eugène. January 1905 (has links)
Th.--Méd.--Paris, 1904-1905. / Paris, 1904-1905, t. 29, n ° 480.
15

Clarification des eaux potables en Algérie par l'utilisation des polymères basiques d'aluminium.

Kettab, Ahmed, January 1900 (has links)
Th. doct.-ing.--Nancy, I.N.P.L., 1981.
16

Dureza en aguas de consumo humano y uso industrial, impactos y medidas de mitigación. Estudio de caso: Chile

Neira Gutiérrez, Marco Antonio January 2006 (has links)
No description available.
17

Aplicación de los sistemas de información geográfica a la gestión técnica de redes de distribución de agua potable.

Martínez Solano, Francisco Javier 13 January 2015 (has links)
El estudio de una red de distribución de agua potable, bien para conocer su comportamiento hidráulico, bien para ejercer una gestión eficaz de los recursos que la componen, exige el manejo de una importante cantidad de información. Esta información posee distinta naturaleza, aunque podría ser agrupada en tres grandes grupos según la misma y el uso a que será sometida. Estos grupos son: información física de los elementos de la red, información económica del sistema de abastecimiento e información espacial sobre la ubicación de los anteriores. Tradicionalmente, esta información se ha guardado en distintos formatos. La información sobre los elementos de la red (diámetros, longitudes, fechas de puesta en operación, proveedores, etc.) quedaba guardada en planos de obra o pequeñas bases de datos de inventario. La información económica quedaba como la base de datos más cuidada del sistema, donde quedaban registrados todos los datos relativos a los abonados, sus consumos, direcciones, fechas de alta y otros datos necesarios para una correcta gestión económica del abastecimiento. Por último, la información espacial se encontraba dispersa en distintos planos topográficos donde aparecían las curvas de nivel del área geográfica abastecida, la ubicación de las tuberías principales y los trazados de las conducciones de distribución, en muchas ocasiones sin actualizar y realizados a mano. En cualquier caso, rara vez existía conexión entre estos tres sistemas de información. Sin embargo, hoy en día es cada vez más frecuente la necesidad de ligar la información sobre las infraestructuras con la económica y ambas a su vez con la componente espacial. Esto es posible gracias a la implantación de un adecuado Sistema de Información Geográfica (SIG). Este sistema nos permite, no sólo relacionar datos de carácter geográfico o espacial con otros datos alfanuméricos, sino también actualizar de una manera sencilla los datos contenidos, a través de una apropiada interfaz gráfica..... / Martínez Solano, FJ. (2002). Aplicación de los sistemas de información geográfica a la gestión técnica de redes de distribución de agua potable [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/46025 / Palancia
18

Legionella pneumophila in Domestic Hot Water Systems: Evaluation of Detection Methods and Environmental Factors Affecting Survival

Strickhouser, Amanda 29 January 2008 (has links)
Legionella is the causative agent of Legionnaires' disease which hospitalizes 8,000 to 18,000 people in the United States each year. The disease in transmitted through inhalation or aspiration of water containing the bacterium and can be acquired within the home. Studies have found that 0-37% of domestic water heaters contain Legionella, making household hot water systems a potential route of exposure. The objective of this research was to evaluate different methods for testing environmental samples for Legionella pneumophila and to analyze potable water conditions that affect survival of free living Legionella pneumophila in hot water tanks. Three heat pretreatment methods (50ºC for 30 minutes, 55ºC for 15 minutes, and 60ºC for 3 minutes) were not effective at recovering Legionella in this study. There was no statistically significant difference between the three acid pretreatment methods that were tested (pH 2.0 with a neutralizing solution, pH 2.2, and the CDC method). Six media (BCYE, DGVP, PCV, GPCV, CCVC, and GPVA) exhibited similar Legionella recovery, except for when high levels of non-Legionella organisms were present, in which case BCYE demonstrated lower recovery. When disinfectant was present, if sodium thiosulfate was not added before the disinfectant, Legionella recovery was lower. However, this result was not statistically significant for free chlorine until after 5 minutes. Pseudomonas aeruginosa (up to 67.5 cfu/ml) and pyocyanin (up to 9 mg/l) did not have an effect on Legionella recovery under the tested conditions. Environmental factors affecting survival of free living Legionella pneumophila in hot water tanks were also studied. After one day exposure in small-scale simulated water heaters at 55ºC, viable Legionella could not be recovered. At 44ºC, Legionellae were recovered after one day but only at very low levels after eight days. Between 23 and 37ºC, Legionella could survive longer than eight days. Copper (Cu²⁺) concentrations above 2160 ppb were found to be toxic to Legionella, but iron (Fe³⁺) between 1 and 2160 ppb did not affect survival. Above pH 11 survival was greatly reduced. No effect was observed between pH 5-10. When glass fiber filters were added to the reactors and they were seeded with tap water and sediment slurry, Legionellae were retained in 7 of 16 reactors for 327 days. The results of this work will assist in optimal identification of Legionella via microbial analysis of potable water samples, thereby assisting in prevention and diagnosis of factors contributing to Legionnaires' disease, especially in settings with high-risk patients (e.g. hospitals). Water systems studying Legionella amplification in domestic hot water systems can use simulated or real distribution system sampling to reproduce and study factors that prevent or reduce Legionella growth and persistence. / Master of Science
19

Microorganisms and Functional Genes Associated with Cometabolic Degradation of 1,4-Dioxane in Biologically-Active Carbon Biofilters Applied for Potable Reuse Treatment

Scott, Katherine Denise 26 June 2024 (has links)
1,4-dioxane is a probable human carcinogen frequently found in water and wastewater systems at concentrations above the EPA one-in-one-million cancer risk level of 0.35 ug/L. 1,4-dioxane is not well removed through conventional treatment methods due to its polarity and resistance to biodegradation, especially when present at low (μg/L) concentrations. Cometabolic degradation of 1,4-dioxane has been achieved in groundwater remediation by stimulating bacteria carrying cyclic ether-degrading soluble diiron monooxygenases (SDIMOs) through the addition of simple alkane gases, such as propane. A recent pilot-scale study demonstrated that addition of such co-substrates prior to biological active filtration (BAF) holds potential as a novel potable reuse treatment approach that can effectively remove 1,4-dioxane. Characterization of the microbial communities associated with propane-induced cometabolism of 1,4-dioxane has largely been limited to culture or polymerase chain reaction (PCR)-dependent methods, which are highly limited in throughput, generally providing information about one organism or one gene at a time. Shotgun metagenomic sequencing is a high-throughput nontargeted means of broadly profiling microbial taxa and functional genes involved in various metabolic processes. In this thesis, methods for DNA extraction from granular activated carbon applied to full-scale BAF amended with propane for the purpose of 1,4-dioxane cometabolism were optimized and metagenomic sequencing was performed. Insights were gained into the microbes and functional genes involved in 1,4-dioxane biodegradation, furthering our understanding of a potentially powerful new water reuse treatment technology that effectively polishes recalcitrant contaminants. / Master of Science / Water reuse systems use advanced wastewater treatment technologies to treat wastewater to such high standards that it can even be used as a source for drinking water. Expanding water reuse is a vital means of protecting water resources, but the treatments can be very costly. Biofiltration is a reuse treatment technology in which water is filtered through media - such as activated carbon - that is commonly used in household filtration systems, providing surface area for the growth of beneficial microorganisms that can naturally biodegrade contaminants in the water. Some contaminants are more difficult to degrade than others, especially trace levels of pharmaceuticals and personal care products. One common manufacturing ingredient that ends up in wastewater and is difficult to biodegrade is 1,4-dioxane, a compound that is potentially carcinogenic to humans at μg/L concentrations when consumed via drinking water over a lifetime. It was recently discovered that adding propane to a biofilter can help to improve biodegradation of 1,4-dioxane down to very low levels. Propane acts as a co-metabolite, i.e., providing a food source on which 1,4-dioxane-degrading bacteria can thrive. In this study, DNA sequencing technology was applied to help identify the bacteria that are responsible for co-metabolic degradation of 1,4-dioxane in a granular activated carbon biofilter. The research was conducted at a demonstration-scale research facility that is investigating innovative ways to treat wastewater to levels that are suitable for recharging a groundwater aquifer that is used as a drinking water source. The main contributions of this study include an optimized protocol for obtaining DNA from the BAF media for DNA sequencing and new insight into the bacteria and enzymes involved in co-metabolic degradation of 1,4-dioxane.
20

Estudio Hidro - Oceanográfico del proyecto de ampliación y mejoramiento de los sistemas de agua potable y alcantarillado del macro proyecto Pachacutec - Ventanilla

Figueroa Torres, Edgar Orlando January 2013 (has links)
El presente Estudio Hidro-Oceanográfico es de suma importancia en el proyecto, para una concepción de la ingeniería de detalle. Asimismo sin este, podríamos encarecer el proyecto por varios motivos, tales como: sobredimensionamiento en la longitud del emisor submarino, excesivo dragado, mayor pago por el derecho de uso de área acuática, etc. Es más, podríamos fracasar con todo el proyecto, debido al retorno de los efluentes hacia la costa, causando una alta contaminación costera. El informe comprende aspectos relacionados con la Hidrografía, Oceanografía, Meteorología y Cartografía de la zona en estudio. El informe técnico se desarrollará en tres capítulos, en el Capítulo I se describe el objetivo del estudio y las especificaciones técnicas de los trabajos geodésicos, topográficos, batimétricos, oceanográficos y la cartografía de la zona de estudio.

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