555 research outputs found
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Innovating on Well Biofouling Remediation: A Bacteriophage Cocktail Approach
Waller Creek Working Grou
Interregional Interdependence among Ecuadorian Provinces: An Input-Output Analysis
In this paper, we explore the structural characteristics of the interregional input-output system developed for Ecuador for the year 2007. As part of an ongoing project that aims to develop an interregional CGE model for the country, this database was developed under conditions of limited information. It provides the opportunity to better understand the spatial linkage structure associated with the national economy in the context of its 22 provinces, 15 sectors and 60 different products. This exploratory analysis is based on the description structural coefficients and the use of traditional input-output techniques. Finally, we further explore the spatial linkage structure by looking at the decomposition of final demand components. It is hoped that this exercise might result in a better appreciation of a broader set of dimensions that might improve our understanding of the integrated interregional economic system in Ecuador.
Interregional input-ouptut system for Ecuador, 2007: methodology and results
In this paper, we explore the structural characteristics of the interregional input-output system developed for Ecuador for the year 2007. As part of an ongoing project that aims to develop an interregional CGE model for the country, this database was developed under conditions of limited information. It provides the opportunity to better understand the spatial linkage structure associated with the national economy in the context of its 22 provinces, 15 sectors and 60 different products. This exploratory analysis is based on the description of structural coefficients and the use of traditional input-output techniques. Finally, we further explore the spatial linkage structure by looking at the regional decomposition of final demand. It is hoped that this exercise might result in a better appreciation of a broader set of dimensions that might improve our understanding of the integrated interregional economic system in Ecuador.Interregional input-output model; Ecuador; spatial linkages
Diseño de micro/nanomotores tipo Jano de ZnO/Fe3O4 y estudio de sus mecanismos de movimiento
En el presente trabajo se empleó el método de
control térmico de partículas embebidas, con el objetivo de diseñar partículas tipo
Jano, esto es, partículas asimétricas conformadas en un extremo por un material y
en el otro extremo por otro material, generando así dos “caras” en la misma
partícula. Para ello, se llevó a cabo la síntesis de magnetita mediante
coprecipitación y las partículas obtenidas fueron encapsuladas con SiO2 mediante
el método de Stöber, con el fin de incrementar su tamaño. Posteriormente, dichas
partículas se depositaron sobre un sustrato de polimetilmetaacrilato mediante spin
coating, después se trató térmicamente a 120 °C durante 1 h para provocar una
inmersión parcial de las partículas, y la cara expuesta se hizo reaccionar con Zn(OH)2 para finalmente desprender las partículas mediante lavados con solventes orgánicos y realizar un tratamiento térmico a 300 °C durante 4 h para obtener las partículas de ZnO/Fe3O4@SiO2. Los materiales obtenidos fueron caracterizados mediante difracción de rayos X, microscopía electrónica de barrido y espectroscopía de energías dispersivas de rayos X
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A phage cocktail approach for the control of iron bacteria from biofouled water supply wells
Biofouling refers to the accumulation of biofilm and biogenic precipitates on wetted surfaces and is one of the major problems associated with groundwater production. Groundwaters rich in ferrous iron (Fe(II)) are particularly susceptible to biofouling due to the low energetic yield of Fe(II) oxidation, which forces ironoxidizing bacteria to convert large quantities of soluble Fe(II) to insoluble ferric iron (Fe(III)) to sustain growth. Bacteria-specific viruses, known as bacteriophages or phages, are particularly promising for biofilm control given their specificity and ability to spread from one host cell to another. Phage therapy for biofilm control has been most successful with pure cultures and low-diversity bacterial communities. However, the applicability of phages to control mixed bacterial communities, in particular those of groundwater supply wells, remains largely unexplored. To assess whether phages constitute an effective alternative to treat well biofouling, the microbial communities of two biofouled wells were interrogated by 16S rRNA gene sequencing. Potential key species of iron bacteria (FeB) were identified and enriched by repeated subculturing in vii Modified Wolfe and Winogradsky media. Mixed phage suspensions were extracted by filtration from activated sludge, and this suspension was enriched against bacterial enrichment cultures developed from well water inocula. Batch tests showed a decrease in cell density and an impairment in iron redox cycling on well enrichment cultures when exposed to phage suspensions. Future work includes testing the phage suspensions against mixed biofilms of FeB, characterizing the specificity of these phage suspensions, and evaluating the impact of the phage on iron redox cycling under other culture conditions. Overall, this work is a first step toward a sustainable rehabilitation approach for biofouled wells.Civil, Architectural, and Environmental Engineerin
Microfluidic synthesis and assembly of noble metal nanoparticle for surface-enhanced vibrational spectroscopies
Dans le présent travail, différents réacteurs microfluidiques ont été conçus et fabriqués pour la synthèse microfluidique de nanoparticules d'Ag et d'Au, en utilisant un système de génération de gouttelettes par flux segmenté. Tout d'abord, la fabrication de dispositifs microfluidiques PDMS/verre a été réalisée en utilisant la méthode de lithographie douce qui permet leur obtention de manière reproductible. Cependant, le mélange des propriétés de surface entre les matériaux ne permettait pas de contrôler la reproductibilité des synthèses en raison de problèmes de colmatage à travers les canaux et de coalescence au sein des gouttelettes, provoquant des perturbations de vitesses sur les fluides, et des dépôts de croissance d'Ag au sein des canaux. Pour cette raison, un réacteur microfluidique tubulaire a été fabriqué. Ceci,ayant la même propriété de surface dans tout le réacteur, a permis l'obtention de nanoparticules d'Ag et d'Au avec des morphologies sphériques et des tailles de 7 et 15 nm, respectivement. De plus, ces nanoparticules présentaient unLSPR à 400 nm pour Ag et 520 nm pour Au, caractéristiques de ces métaux. D'autre part, les dispositifs microfluidiques Si/Pyrex sont conditionnés et fabriqués pour une utilisation ultérieure en tant que substrat microfluidique SERS. Celles-ci ont été fonctionnalisées par un procédé de silanisation avec du 3-mercaptopropyltriméthoxysilane pour assembler les nanoparticules de métaux nobles à la surface de leurs microcanaux. Par la suite, des nanoparticules d'Au ont été passées à travers les microcanaux des dispositifs microfluidiques à 80 μL h-1, puis du 4-aminothiophénol a été passé à 20 μL h-1 comme molécule test pour son évaluation dans la spectroscopie Raman augmentée sur des surfaces, en observant une analyse facteur de grossissement de 17 sur les signaux caractéristiques de cette molécule à 1590 et 1080 cm-1, concluant que la synthèse et l'assemblage microfluidique de nanoparticules de métaux nobles est une alternative pour l'analyse SERS.In the present work, different microfluidic reactors were designed and fabricated for the microfluidic synthesis of Ag and Au nanoparticles, using a droplet generation system through segmented flow. First, the fabrication of PDMS/glass microfluidic devices was carried out using the soft lithography method which allow their obtainment in a reproducible way. However, the mixture of surface properties between the materials did not allow to control the reproducibility of the syntheses due to clogging problems through the channels and coalescence within the droplets, causing velocities disruptions on the fluids, and Ag growth deposits within the channels.Because of this, a tubular microfluidic reactor was fabricated. This, having the same surface property throughout the reactor, allowed the obtaining of Ag and Au nanoparticles with spherical morphologies and sizes of 7 and 15 nm, respectively. In addition, these nanoparticles presented an LSPR at 400 nm for Ag and 520 nm for Au, characteristics of these metals.On the other hand, Si/Pyrex microfluidic devices are conditioned and manufactured for later use as a SERS microfluidic substrate. These were functionalized through a silanization process with 3-mercaptopropyltrimethoxysilane to assemble the noble metal nanoparticles on the surface of their microchannels.Subsequently, Au nanoparticles were flowed through the microchannels of the microfluidic devices at 80 μL h-1 and then 4-aminothiophenol was flowed at 20 μL h-1 as a test molecule for its evaluation in the augmented Raman spectroscopy on surfaces, observing An analytical magnification factor of 17 on the characteristic signals of this molecule at 1590 and 1080 cm-1, concluding that the synthesis and microfluidic assembly of noble metal nanoparticles is an alternative for SERS analysis
Avaliação do efeito de usinas eólicas sobre a capacidade de regularização de um sistema hidrelétrico
Orientador : Prof. Dr. Daniel Henrique Marco DetzelCo-Orientadora: Prof.a Dra. Miriam Rita Moro MineDissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia de Recursos Hídricos e Ambiental. Defesa : Curitiba, 13/12/2017Inclui referênciasResumo: A participação da energia eólica na matriz energética brasileira tem aumentado consideravelmente. Dentre os principais desafios técnicos oferecidos por esse tipo de energia se encontram a variabilidade e a incerteza do vento, que exigem atenção na operação e no planejamento do sistema elétrico e não permitem uma regularização própria. Para garantir uma geração firme é necessário dispor de outra fonte com capacidade de regularização que complemente a energia eólica, tal como a geração hidráulica, usando a energia armazenada nos reservatórios de regularização do sistema hidrelétrico. A presente dissertação procura quantificar os impactos na energia armazenável e a perda de energia firme de um sistema hidrelétrico ao usar parte dos reservatórios hidrelétricos para regularizar a geração eólica. O problema foi analisado através de um estudo de caso considerando o sistema hidrelétrico da bacia do rio São Francisco, que possui 97% da capacidade de armazenamento da região Nordeste, e um parque eólico fictício localizado no município brasileiro de Parnaíba, no extremo norte do Estado do Piauí. Para o sistema hidrelétrico foram utilizados dados mensais de vazão natural e para a geração eólica foram utilizados dados horários de velocidade de vento. Para a avaliação da energia hidrelétrica foi aplicado o Método da Energia Natural e foram geradas séries sintéticas a partir de um modelo Markoviano de primeira ordem. Para a avaliação da geração eólica foram gerados diferentes cenários a partir de um incremento gradual da potência instalada do parque eólico e do aumento gradual da variabilidade do vento alterando o Coeficiente de Variação da série de velocidade de vento. A máxima potência dos cenários avaliados delimitou-se em base à capacidade eólica instalada atualmente no Nordeste e o máximo incremento do Coeficiente de Variação foi determinado com base no comportamento do vento em diferentes regiões do Brasil. A avaliação hidroeólica foi baseada na determinação e no uso das Curvas de Regularização do sistema hidrelétrico e dos diferentes cenários de geração eólica determinados. Os resultados para os sistemas avaliados mostram que, em porcentagem, a máxima redução do armazenamento hidrelétrico para garantir uma energia firme eólica com um nível de regularização de 90% é de 28%, representando uma redução de 8,6% da energia firme hidrelétrica. Os resultados também mostram que a variabilidade na produção horária de energia eólica tem um grande impacto no âmbito energético já que para um nível de regularização eólica de 90%, o armazenamento se reduz em 41%, representando uma redução de 12,7% da energia firme eólica para o cenário com maior incremento do Coeficiente de Variação na série de velocidade de vento. Palavras-chave: Energia eólica. Complementação hidroeólica. Regularização de vazões.Abstract: The participation of wind power in the Brazilian energy matrix has increased considerably. One of the main technical challenges offered by this type of energy is the wind variability and uncertainty, which requires attention in the operation and planning of the electric system and does not allow proper energy regulation. To guarantee a firm generation it is necessary to have another source with regulation capability that complements the wind energy, such as a reservoir-based hydroelectric system. The importance of water storage is increasing and a careful analysis is needed so that the system guarantees supply in the most critical situations. The main purpose of this work is to analyze the impacts on water storage and the loss of firm energy in a hydroelectric system by the use of hydroelectric reservoirs to regulate wind generation. The problem was analyzed via a case study considering the hydroelectric system of the São Francisco river basin, which has 97% of the water storage capacity of the Northeast region, and a fictitious wind farm located in the Brazilian municipality of Parnaíba, in the State of Piauí. For the hydroelectric system monthly natural flow data where used and for the wind generation hourly wind speed data were considered. For the hydroelectric evaluation, the Natural Energy Hydrograph method was applied, together with a first order Markovian model to synthetic series generation. For the evaluation of wind generation, different scenarios were obtained from a gradual increase of the wind farm installed capacity and the gradual increase of wind variability by increasing the wind speed series coefficient of variation. The maximum installed capacity of the wind farm's scenarios was delimited based on the actual wind energy installed capacity of the Northeast region. The maximum increase of the coefficient of variation was determined based on the wind behavior in different regions of Brazil. The hydro-wind evaluation was based on the determination and use of the Regularization Curves of the hydroelectric system and the different wind generation scenarios. The results show that, in percentage, the maximum reduction of hydroelectric water storage to guarantee a firm wind energy with a 90% regularization level is 28%, representing a reduction of 8,6 % of the hydroelectric firm energy. The results also show that the variability in the hourly production of wind energy has a great energy impact since at a level of wind regulation of 90%, the hydroelectric water storage reduces by 41%, representing a reduction of 12,7% of the hydroelectric firm energy for the scenario with the greatest coefficient of variation increase in the wind speed series. Keywords: Wind energy. Hydro-wind complementation. Streamflow regulation
Aplicación de termoplásticos en la industria colombiana
Se describen los productos diseñados para manejar fluidos líquidos y para solucionar los problemas de abrasión y corrosión con los materiales que tradicionalmente se manejaban.
Análisis de los procesos de recreación y construcción audiovisual de la película La muralla verde de Armando Robles Godoy
Explica el proceso el proceso de recreación de la novela La muralla verde, escrita entre 1955 y 1956 por Armando Robles Godoy, en la película homónima que dirigió él mismo en 1969. Para tal fin, se plantea comprender el concepto de “recreación” aplicado por el autor en dicho procedimiento e identificar las características de cada uno de los textos para poder, finalmente, reconocer y explicar las analogías y las divergencias existentes entre ambos. Se explica el proceso de construcción audiovisual de la película La muralla verde y para ello propone reconocer las influencias cinematográficas para realizar el film así como identificar los recursos expresivos aplicados en su construcción audiovisual
Rol de la Defensoría del Pueblo en la solución de conflictos de Babahoyo, Ecuador 2018
El estudio nace porque se ha evidencia que, en la Defensoría del Pueblo de la ciudad de
Babahoyo, no se ha trabajado considerando una planificación estratégica que permita una
gestión eficiente, esto ha generado problemas que afecta a la ciudadanía, que se refleja en
la poca asistencia en búsqueda de ayuda, a su vez esto desmotiva a los funcionarios a
desarrollar su accionar con eficiencia y eficacia.
Por ello, se buscó Determinar el rol de la Defensoría del Pueblo y su relación con la
solución de conflictos de Babahoyo, Ecuador 2018; la investigación fue realizada bajo el
paradigma positivista y el enfoque cuantitativo; fue de nivel descriptivo y tipo
correlacional. Se usó la técnica de la encuesta con los instrumentos cuestionario sobre las
variables rol de la Defensoría del Pueblo y solución de conflictos, ambos instrumentos
fueron validados por expertos y se sometieron a pruebas de confiabilidad. Se aplicaron
ambos instrumentos a 35 abogados que tienen a su cargo casos por resolver en la
Defensoría del Pueblo, la selección de la muestra fue no probabilística.
La variable rol de la Defensoría del Pueblo estuvo compuesta por 3 dimensiones: Rol
defensa de los derechos, atención de quejas y rol conciliador, variable solución de
conflictos se dimensionó a través de 4 aspectos: Supervisión preventiva, acciones legales,
intermediación y mediación. Las principales conclusiones a las que arribo el siguiente
estudio fueron:
Se rechaza la hipótesis general nula y se acepta la hipótesis general positiva; el rol que
cumple la Defensoría del Pueblo se relaciona significativamente con la solución de
conflictos, estos resultados se contrastan con las teorías planteadas y con los antecedentes
de investigación citados; respecto a las dimensiones resultó que las tres dimensiones rol
defensa de los derechos, atención de quejas y rol conciliador correlacionan
significativamente con la variable solución de conflictos en la Defensoría del Pueblo de
Babahoyo, Ecuador – 2018
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