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Impact of a Programme for Water Affordability on Residential Consumption: Implementation of the <em>“Programa Mínimo Vital de Agua Potable”</em> in Bogotá, Colombia Texte intégral
2018
Vargas, Laura | Mingoti, Sueli Aparecida | Heller, Léo
Impact of a Programme for Water Affordability on Residential Consumption: Implementation of the <em>“Programa Mínimo Vital de Agua Potable”</em> in Bogotá, Colombia Texte intégral
2018
Vargas, Laura | Mingoti, Sueli Aparecida | Heller, Léo
Affordability of services is a determinant for people’s level of access to water. In this study, we analyse the effect of a programme aimed at improving the affordability of water services on users’ water consumption. The programme was implemented in 2012 by the local government of the city of Bogotá, Colombia, intending to provide an essential “lifeline” volume of water to poor households free of charge. Our assessment was carried out with secondary data and used difference-in-difference estimators in a panel data analysis of a two-period sample: 2011 and 2014. The unit of analysis was defined based on the city’s administrative divisions and the socio-economic stratification of residences. Over the period analysed, beneficiaries’ household consumption increased, reaching per capita consumption levels closer to those of the upper strata of users. Results suggest that the programme contributes to increased consumption and equity among users.
Afficher plus [+] Moins [-]Impact of a Programme for Water Affordability on Residential Consumption: Implementation of the “Programa Mínimo Vital de Agua Potable” in Bogotá, Colombia Texte intégral
2018
Laura Vargas | Sueli Aparecida Mingoti | Léo Heller
Affordability of services is a determinant for people’s level of access to water. In this study, we analyse the effect of a programme aimed at improving the affordability of water services on users’ water consumption. The programme was implemented in 2012 by the local government of the city of Bogotá, Colombia, intending to provide an essential “lifeline” volume of water to poor households free of charge. Our assessment was carried out with secondary data and used difference-in-difference estimators in a panel data analysis of a two-period sample: 2011 and 2014. The unit of analysis was defined based on the city’s administrative divisions and the socio-economic stratification of residences. Over the period analysed, beneficiaries’ household consumption increased, reaching per capita consumption levels closer to those of the upper strata of users. Results suggest that the programme contributes to increased consumption and equity among users.
Afficher plus [+] Moins [-]Water quality of the Grijalva river on the Chiapas - Tabasco border/ Calidad de agua del río Grijalva en la frontera de Chiapas y Tabasco Texte intégral
2018
Musálem-Castillejos, Karim | Laino-Guanes, Rafaela | Bello Mendoza, Ricardo | González-Espinosa, Mario | Ramírez-Marcial, Neptalí
Water quality of the Grijalva river on the Chiapas - Tabasco border/ Calidad de agua del río Grijalva en la frontera de Chiapas y Tabasco
2018
Musálem-Castillejos, Karim | Laino-Guanes, Rafaela | Bello Mendoza, Ricardo | González-Espinosa, Mario | Ramírez-Marcial, Neptalí
he objective was to characterize the water quality in a section of the Grijalva River and in some of its tributaries on the border between the States of Chiapas and Tabasco, in the rainy and dry seasons. Twenty-three physical, chemical and microbiological parameters as well as contaminants were determined. The values obtained were compared with the maximum permissible limits (MPLs) for water use and human consumption set out in O cial Mexican standard NOM-127-SSA1-1994, and with the water quality classi cation scale of the Comisión Nacional del Agua (CONAGUA). The water quality in the studied section of the Grijalva River decreases as it descends to more populated areas of the State of Tabasco. Water turbidity and E. coli coliform levels increase, both in the river channels and in sources destined for human consumption. For the other variables evaluated, there are acceptable water quality characteristics, mainly in the dry season, except for mercury, which occurs at levels higher than those recommended. Further studies on the presence of mercury in the Grijalva River basin are recommended.
Afficher plus [+] Moins [-]Water quality of the Grijalva river on the Chiapas - Tabasco border/ Calidad de agua del río Grijalva en la frontera de Chiapas y Tabasco Texte intégral
2018
Karim Musálem-Castillejos | Rafaela Laino-Guanes | Ricardo Bello-Mendoza | Mario González-Espinosa | Neptalí Ramírez-Marcial
he objective was to characterize the water quality in a section of the Grijalva River and in some of its tributaries on the border between the States of Chiapas and Tabasco, in the rainy and dry seasons. Twenty-three physical, chemical and microbiological parameters as well as contaminants were determined. The values obtained were compared with the maximum permissible limits (MPLs) for water use and human consumption set out in O cial Mexican standard NOM-127-SSA1-1994, and with the water quality classi cation scale of the Comisión Nacional del Agua (CONAGUA). The water quality in the studied section of the Grijalva River decreases as it descends to more populated areas of the State of Tabasco. Water turbidity and E. coli coliform levels increase, both in the river channels and in sources destined for human consumption. For the other variables evaluated, there are acceptable water quality characteristics, mainly in the dry season, except for mercury, which occurs at levels higher than those recommended. Further studies on the presence of mercury in the Grijalva River basin are recommended.
Afficher plus [+] Moins [-]Sensor colorimétrico à base de polidiacetileno para detecção de agrotóxicos em água | Colorimetric sensor based on polydiacetylene for the detection of pesticides in water Texte intégral
2017
Carioca, Leonardo Justino | Andrade, Nélio José de | http://lattes.cnpq.br/3277248021770910 | Pires, Ana Clarissa dos Santos | Peña, Wilmer Edgard Luera
Os agrotóxicos são produtos e agentes de processos físicos, químicos ou biológicos utilizados para o controle de pragas, doenças e plantas daninhas que acometem as plantações de todo o mundo. Eles representam um grande risco à saúde da população por conter compostos cancerígenos e provocarem doenças que podem levar à morte. Geralmente, a detecção desses compostos na água é realizada por métodos cromatográficos que envolvem alto custo e requer profissionais capacitados. O objetivo dessa pesquisa foi desenvolver um método alternativo para detecção de determinados agrotóxicos em água por meio um sensor colorimétrico utilizando vesículas de polidiacetileno (PDA). Para desenvolver o sensor, foram prepadas vesículas de 10,12 ácido pentacosadinóico (PCDA) + 10, 12- ácido tricosadinóico (TRCDA) com adição de esfingomielina (ES) + colesterol (CO). Dentre nove produtos comerciais testados, apenas quatro suspensões mudaram a cor quando incubados em banho-maria a 32 oC nos tempos de 0 h, 24 h e 48 h. Os produtos comerciais testados foram Roundup Original® (herbicida) 52% m/v, Tacora® 250EW (fungicida) 25% m/v, Decis® 25EC (deltametrina) 2,5% m/v (inseticida) e FEGATEX® (tensoativo/fungicida) 10% m/v. Ao avaliar a quantidade mínima de detecção (QMD) pode-se observar que a transição de cor ocorreu, sendo o fungicida o que obteve a menor QMD (300 mg/L) e o inseticida a maior (720 mg/L). As suspensões de vesículas foram contaminadas com s oluções desses agrotóxicos nas seguintes concentrações 0 μg·L -1 , 180 μg·L - , 250 μg·L -1 , 400 μg·L -1 , 500 μg·L -1 , 600 μg·L -1 , 750 μg·L -1 , 850 μg·L -1 , 1000 μg·L -1 , 1200 μg·L -1 e 1500 μg·L -1 dos princípios ativos .A mudança da cor azul foi percebida sem, no entanto, diferenciar as concentrações. Essas diferenças foram detectadas somente pela determinação das Respostas Colorimétricas (RC). | Agrochemicals are products and agents of physical, chemical or biological processes used to control pests, diseases and weeds that occur as plantations all over the world. They pose a major health risk to the population because they contain carcinogenic compounds and cause diseases that can lead to death. Generally, a detection of compounds in water is performed by chromatographic methods that involve high cost and trained professional requirements. The objective of this research is to develop an alternative method for the detection of certain pesticides in water by means of the colorimetric sensor using the polydiacetylene vesicles (PDA). For the development of the sensor, vesicles of 10.12 pentacosadinoic acid (PCDA) + 10, 12-tricosadinoic acid (TRCDA) were prepared with addition of sphingomyelin (ES) + cholesterol (CO). Among nine commercial products tested, only four suspensions changed color when incubated in a water bath at 32 ° C at 0 h, 24 h and 48 h times. The commercial products tested were Roundup Original® (herbicide) 52% m / v, Tacora® 250EW (fungicide) 25% m / v, Decis® 25EC (deltamethrin) 2.5% m / v (insecticide) and FEGATEX® / fungicide) 10% m / v. In order to evaluate a minimum amount of detection (QMD), it can be observed that a transition of labor, with the fungicide being the lowest QMD (300 mg / L) and the largest insecticide (720 mg / L) . A-1, 180 μg · L-1, 250 μg · L-1, 400 μg · L-1, 500 μg · L-1, 600 μg · L-1, 750 μg · L-1, 850 μg · L-1, 1000 μg · L-1, 1200 μg · L-1 and 1500 μg · L-1 of the active principles. The change of the blue color was perceived without, however, differentiating the concentrations. These images were detected only by determination of the Colorimetric Responses (CR). | Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Afficher plus [+] Moins [-]Caracterização do lodo de estações de tratamento de água de Porto Alegre/RS | Characterization of sludge of water treatment stations os Porto Alegre/RS Texte intégral
2017
Acquolini, Gabriela Tirello | Camargo, Flavio Anastacio de Oliveira | Ojeda, Telmo Francisco Manfron
O grande adensamento antrópico nas metrópoles tem aumentado a contaminação e a poluição dos recursos hídricos, que na maioria das vezes abastecem esta mesma população. Com isso, o saneamento básico e seus resíduos relacionados, como o lodo das Estações de Tratamento de Água (ETA) devem ter uma destinação ambientalmente adequada, uma vez que possuem na sua composição predominantemente orgânica, agrotóxicos, metais e produtos químicos. Desta forma, o objetivo desse estudo foi caracterizar o lodo residual de duas estações de tratamento de água do município de Porto Alegre (RS), por meio de análises químicas, biológicas e físicas do lodo, assim como determinar o efeito do lodo em plantas ornamentais a partir da sua disposição no solo. Em complementação foi também realizado a avaliação de alguns parâmetros de qualidade da água do manancial de captação: Guaíba. O lodo foi submetido a análises laboratoriais para diagnóstico de presença de metais, agrotóxicos, coliformes fecais, bem como análises microscópicas e de difratometria de raios X. Além disso, o lodo foi disposto em um Latossolo, com o cultivo de duas espécies ornamentais: Cynodon dactylon e Lobularia marítima (L.) Desv. Também foram realizadas análises de alguns parâmetros de qualidade da água em 28 pontos do Guaíba. Os resultados da análise do lodo residual de duas ETAs identificaram elevadas concentrações de carbono orgânico e de coliformes fecais e não houve detecção de agrotóxicos, classificando o lodo como resíduo Classe II-A – Não-inerte. O uso diluído de lodo no solo em diferentes concentrações não influenciou significativamente a produção de matéria seca de Cynodon dactylon e Lobularia marítima (L.) Desv. A água no lago Guaíba apresenta diferentes níveis de qualidade, sendo que a região mais ao norte do lago apresenta uma qualidade inferior à região sul, que se aproxima da foz. A região próxima ao centro de Porto Alegre é onde a qualidade da água é menor, com destaque para a presença de coliformes fecais em grande quantidade. Entre as fontes de poluição pontual destaca-se a contribuição do Arroio Dilúvio. | The population increase in the big cities has increased contamination and pollution of water resources, which usually could be used to supply this same population. Basic sanitation and its related waste, such as water treatment plant sludge (ETA), must have an environmentally appropriate destination, since they have predominantly organic composition, agrochemicals, metals and chemicals. Thus, the objective of this study was to characterize the residual sludge from two water treatment plants in the city of Porto Alegre (RS), by means of the Guaíba water quality assessment, using chemical, biological and physical analyzes of the sludge as well to determine the effect of sludge addiction to the soil on ornamental plants growth. The sludge was subjected to laboratory analysis to diagnose the presence of metals, pesticides, fecal coliforms, as well as microscopic analysis and X-ray diffraction. In addition, the sludge was disposed in an Oxisol, with the cultivation of two ornamental plants: Cynodon Dactylon and Lobularia maritime (L.) Desv. Guaíba water quality analyzes were also carried out. The results of the residual sludge analysis of two ETAs identified high concentrations of organic carbon and fecal coliforms and no pesticides were detected, classifying the sludge as Class II-A non-inert residue. The diluted use of soil sludge in different concentrations not influenced significantly the dry matter production of Cynodon dactylon and Lobularia maritime (L.) Desv. The water in Lake Guaíba presents different levels of quality, being that the region more to the north of the lake presents a inferior quality to the south region, that approaches the mouth. The region near the downtown of Porto Alegre is more polluted and the quality of water is lower, especially by the presence of fecal coliforms in great quantity. Dilúvio strem is among the main punctual sources of pollution of the Guaiba Lake.
Afficher plus [+] Moins [-]Alternative crop sequences for increasing the forage potential and water productivity | Secuencias de cultivo alternativas para incrementar el potencial forrajero y productividad del agua Texte intégral
2017
Reta Sánchez, David Guadalupe | Serrato Corona, J. Santos | Quiroga Garza, Héctor Mario | Gaytán Mascorro, Arturo | Figueroa Viramontes, Uriel
Intensification of forage production during fall-winter season may improve productivity of cropping systems. The objective of this study was to determine the forage potential and water productivity (WP) of alternative crop sequences with double-crop during fall-winter season. The study was conducted during 2012-2013 y 2013-2014 cycles in Matamoros, Coahuila, México. The alternative crop sequences canola-triticale-corn, canola-barley-corn, canola-safflower-corn and canola-triticale-pearl millet were compared with the conventional crop sequences oat-corn-corn and oat-sorghum-sorghum. Forage chemical composition, dry matter (DM) and nutrient yields, and WP values for DM, crude protein (CP) and net energy for lactation (NEL) production were determined. Alternative crop sequences showed higher yields (11.4-53.3 %) and superior WP values (23.1-58.9 %) in CP production (P<0.05), besides they had water savings from 5.7 to 36 cm as compared with the conventional crop sequence oat-corn-corn. The best alternative sequences were those with the incorporation of canola in fall, barley or triticale in winter, and corn in spring, due to their higher yield and WP in CP (P<0.05). In addition, their WP values for DM (1.92-2.05 kg m-3) and NEL (12.22-13.64 MJ m-3) were similar (P>0.05) or higher (P<0.05) to those for the sequence oat-corn-corn, with 1.65-1.99 kg m-3 for DM and 11.09-13.72 MJ m-3 for NEL. The results show that alternative crop sequences with double-crop during fall-winter season can improve the efficiency of forage production. | La intensificación de la producción de forraje durante el período otoño-invierno puede incrementar la productividad de los sistemas de producción. El objetivo de este estudio fue determinar el potencial forrajero y productividad del agua (PA) de secuencias de cultivo alternativas con doble cosecha en otoño-invierno. El estudio se realizó durante los ciclos 2012-2013 y 2013-2014 en Matamoros, Coahuila, México. Se compararon las secuencias alternativas canola-triticale-maíz, canola-cebada-maíz, canola-cártamo-maíz y canola-triticale-mijo perla con las secuencias convencionales avena-maíz-maíz y avena-sorgo-sorgo. Se determinó la composición química del forraje, los rendimientos de materia seca (MS), nutrientes y PA en la producción de MS, proteína cruda (PC) y energía neta para lactancia (ENL). Las secuencias alternativas mostraron mayores rendimientos (11.4-53.3 %) y valores superiores de PA (23.1-58.9 %) en la producción de PC (P<0.05), además de ahorros en lámina de riego anual de 5.7 a 36.0 cm al compararse con la secuencia convencional avena-maíz-maíz. Las mejores secuencias alternativas fueron las que incluyeron canola en otoño, cebada o triticale en invierno, y maíz en primavera, debido a su mayor rendimiento y PA en PC (P<0.05); además, sus valores de PA para MS (1.92-2.05 kg m-3) y ENL (12.22-13.64 MJ m-3) fueron similares (P>0.05) o mayores (P<0.05) a los de la secuencia avena-maíz-maíz con 1.65-1.99 kg m-3 para MS y 11.09-13.72 MJ m-3 para ENL. Los resultados indican que las secuencias alternativas con doble cosecha en otoño-invierno pueden mejorar la eficiencia de producción de forraje.
Afficher plus [+] Moins [-]Tendencias en el consumo urbano de agua en el litoral alicantino (2000-2014) | Trends in urban water consumption in the Alicante coastline (2000-2014) Texte intégral
2017
Villar Navascués, Rubén Alejandro | Universidad de Alicante. Instituto Interuniversitario de Geografía
Este trabajo pretende analizar la evolución del consumo urbano de agua y sus principales causas para la mayor parte de los municipios del litoral alicantino durante el periodo 2000-2014. A partir de la elaboración de una base de datos sobre consumo urbano de agua se han analizado las tendencias observadas para cuatro ámbitos territoriales del litoral, que coinciden con los límites comarcales. Los resultados de este análisis muestran que, tras un periodo de crecimiento de la demanda a principios de la década del 2000, se produjo una tendencia decreciente generalizada en toda la costa. Algunos de los factores que explican la evolución y desigual distribución de las demandas urbanas de agua entre los municipios litorales son analizados. Sin embargo, los datos de consumo urbano de agua en los últimos años parecen indicar el final de la reducción del consumo e incluso, en algunos casos, un posible crecimiento de la demanda coincidiendo con una caída de la población. Por ello, será necesario que futuras investigaciones identifiquen qué factores están motivando esta evolución para mejorar la planificación y las previsiones sobre el consumo. | This paper analyzes the evolution of urban consumption of water and their main causes for the greater part of the municipalities of the Alicante coast during the period 2000-2014. The results of this analysis show that, after a period of growth in demand at the beginning of the 2000s, there was a decreasing trend in the coast. Some of the factors that explain the evolution and unequal distribution of urban coastal municipalities water demands are analyzed. However, the data of urban water consumption in recent years seem to indicate the end of the reduction of consumption and even, in some cases, a possible growth of demand coinciding with a fall in the population. Therefore, it will be necessary for future research to identify which factors are motivating this evolution to improve the planning and forecasting of consumption. | Este artículo se inserta en una beca pre-doctoral de Formación de Personal Universitario del Programa Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (FPU15/01144) y en el proyecto de investigación “Uso y Gestión de recursos hídricos no convencionales en el litoral de las regiones de Valencia y Murcia como estrategia de adaptación a la sequía” (CSO2015-65182-CS-2-P), financiado por el Ministerio de Economía y Competitividad.
Afficher plus [+] Moins [-]Aportes para la gobernanza del agua en el municipio de La Mesa Cundinamarca | Contributions to water governance in the municipality of La Mesa Cundinamarca Texte intégral
2016
Lucumi Rodríguez, Cindy Johana | Avellaneda Cusaria, Jose Alfonso
El agua es un recurso no renovable, imprescindible y principal componente para todos los seres vivos. Aproximadamente, el ser humano está compuesto por el 72% de agua y necesita de este recurso para realizar sus actividades cotidianas. Muchas de las normativas internacionales y nacionales, velan por este recurso, ya que el agua es indispensable para una vida digna y es un derecho de cada ser humano que disponga de agua suficiente, de calidad y asequible para su uso personal y doméstico. A pesar de la época muchas personas no cuentan con el suministro de agua potable diariamente, dando lugar a problemas de subsistencia, desempleo y de progreso. Para ello es importante conocer quiénes son los responsables de la prestación del servicio en el territorio, del manejo del agua y las instituciones involucradas. Hay que tener en cuenta que las actividades de los seres humanos han conllevado a la disminución de las fuentes hídricas, como la tala indiscriminada de árboles, los vertimientos directamente en los afluentes, por esta razón es necesario involucrar a la población entorno a la problemática del agua. Inquiriendo en la conservación y preservación del agua, asegurando las funciones y haciendo posible el uso racional actual y futuro, evitando el momento de no contar con ella. La Mesa es un municipio del departamento de Cundinamarca, donde el suministro de agua potable es deficiente, donde llega dos veces a la semana, hasta el mediodía y en algunas ocasiones tres horas al día o llega por medio de carrotanques, es un municipio que se caracteriza por dominio agrícola cultivos de frutas cítricas, pero con la escasez del agua, los cultivos tiene que esperar el agua lluvia, para cumplir sus ciclo productivo. Las fuentes hídricas presentes, han disminuido su caudal debido al cambio climático y la deforestación, originando un desequilibrio ecológico. El enfoque de esta investigación es cualitativo, donde el instrumento predominante para la recolección de información, se dio por la observación directa, sumada a entrevistas semiestructuradas a la población de las veredas, encuentros de los actores involucrados del uso y manejo del recurso hídrico, con la posibilidad de conocer el escenario actual del municipio y conocer las problemáticas vigentes. Enfocando el término gobernanza del agua en el municipio, se dio una breve reseña del concepto, conociendo las normas vigentes con respecto al agua, tanto internacional como nacional. Damos a conocer la importancia y la necesidad de la participación ciudadana “toma de decisiones”, en la gestión del agua y todo lo relacionado con ella. Este mecanismo promoverá un intercambio de conocimientos, diálogos, sentido de pertenencia, responsabilidades y actividades compartidas, decisiones colectivas, resultados productivos y positivos, no solo se garantizara una justicia social, ni ambiental, lo que se procurar son actividades y proyectos, orientados a una visión integral, contemplando dimensiones políticos, ambientales, sociales y ambientales. El municipio se dividió es cuatro sectores, que corresponden al sector La Mesa, San Joaquín, San Javier y La Esperanza, se realizó un total de 84 encuestas, con preguntas referentes a la disponibilidad del agua, a la conformidad del servicio, a la utilización pozos sépticos, que considera un tema prioritario para su municipio, si hay participación entre otras. Se permio conocer las percepción de cada actor en los encuentros Y finalmente se realizó una búsqueda con respecto a la crisis del suministro de agua, por parte de la prensa nacional. | Ingeniero Ambiental | Pregrado | Main component for all living beings. Approximately 72% of human beings are made up of water and they need this resource to carry out their daily activities. Many of the international and national regulations, watch over this resource, since water is indispensable for a dignified life and it is a right of every human being to have sufficient, quality and affordable water for personal and domestic use. In spite of the times, many people do not have a daily supply of drinking water, giving rise to problems of subsistence, unemployment and progress. For this it is important to know who is responsible for the provision of the service in the territory, water management and the institutions involved. It should be taken into account that human activities have led to the reduction of water sources, such as the indiscriminate felling of trees and direct discharge into the tributaries, for this reason it is necessary to involve the population in the water problem. Inquiring in the conservation and preservation of water, ensuring the functions and making possible the current and future rational use, avoiding the moment of not having it. La Mesa is a municipality in the department of Cundinamarca, where the supply of drinking water is deficient, where it arrives twice a week, until noon and sometimes three hours a day or it arrives by means of tanker trucks, it is a municipality characterized by agricultural domain citrus fruit crops, but with the scarcity of water, the crops have to wait for rainwater to fulfill their productive cycle. The present water sources have decreased their flow due to climate change and deforestation, causing an ecological imbalance. Information was collected through direct observation, in addition to semi-structured interviews with the population of the villages, meetings of the actors involved in the use and management of water resources, with the possibility of knowing the current scenario of the municipality and the current problems. Focusing on the term water governance in the municipality, a brief review of the concept was given, knowing the current norms regarding water, both international and national. The importance and the need for citizen participation "decision making" in water management and everything related to it was made known. This mechanism will promote an exchange of knowledge, dialogues, sense of belonging, shared responsibilities and activities, collective decisions, productive and positive results, not only social and environmental justice will be guaranteed, but also activities and projects oriented to an integral vision, contemplating political, environmental, social and environmental dimensions. The municipality was divided into four sectors, corresponding to La Mesa, San Joaquín, San Javier and La Esperanza. A total of 84 surveys were conducted, with questions regarding the availability of water, the conformity of the service, the use of septic tanks, what is considered a priority issue for the municipality, if there is participation, among others. Finally, a search was carried out in the national press regarding the water supply crisis.
Afficher plus [+] Moins [-]Experimental study of water infiltration on an unsaturated soil-geosynthetic system | Estudio experimental de infiltración de agua en un sistema suelo-geosintético parcialmente saturado Texte intégral
2016
Vega Posada, Carlos Alberto | Gallego Hernández, Alba Nury | Grupo de Ingeniería y Gestión Ambiental (GIGA)
RESUMEN: Esta investigación presenta resultados experimentales de columnas de suelo-geosintético construidas para estudiar la capacidad de drenaje de geosintéticos instalados en suelos parcialmente saturados y sometidos a procesos de infiltración de agua. Se ensayaron dos tipos diferentes de geosintéticos permeables denominados geotextil no tejido y geocompuesto tejido-no tejido. El proceso de infiltración se monitoreó usando sensores de presión de poros negativa/positiva y de contenido volumétrico de agua, los cuales se colocaron por encima y por debajo del geosintético. Los resultados mostraron que los geosintéticos se comportaron como una capa impermeable hasta que el suelo circundante estaba casi saturado. Los geosintéticos empezaron a drenar agua lateralmente solo cuando la presión de poros en el suelo arriba de él era positiva o negativa pero cercana a cero. Este estudio busca proveer algunas ideas sobre la física del funcionamiento de suelo con geotextil y complementar la información técnica existente usada para realizar simulaciones numéricas de estructuras de suelo complejas sometidas a procesos de infiltración. | ABSTRACT: This investigation presents experimental results from soil-geosynthetic column tests constructed to study the drainage capability of geosynthetics installed within an unsaturated soil and subjected to a water infiltration process. Two different types of permeable geosynthetics were tested; namely, non-woven geotextile and woven non-woven geocomposite. The infiltration process was monitored using negative/positive pore water pressure and volumetric water content transducers placed above and below the geosynthetic. The results showed that the geosynthetics behaved as an impermeable layer until the surrounding soil was nearly saturated. The geosynthetics started draining water laterally only when the pore water pressure within the soil above it was positive or negative but close to zero. This study intends to provide some insights into the physics of soil-geosynthetics performance, and to complement the available technical data used to conduct numerical simulations of complex soil-structures subjected to water infiltration processes.
Afficher plus [+] Moins [-]Efeito da aplicação da água eletrolisada fracamente ácida em peitos de frango resfriados | Effects of slight acid electolyzed water of frozen chicken breast meat Texte intégral
2015
Ruviaro, Amanda Roggia | Cichoski, Alexandre José | http://lattes.cnpq.br/8253591322909707 | Barin, Juliano Smanioto | http://lattes.cnpq.br/7545847424095994 | Wagner, Roger | http://lattes.cnpq.br/4780821244553957 | Nespolo, Cássia Regina | http://lattes.cnpq.br/9101858681342985
Chicken meat may suffer rapid deterioration because of spoilage microorganisms. The type and number of microorganisms define quality of the product. Many stuidies show the use of slight acid electrolyzed water (sAEA) with high free clorine concentration (FCC) has been investigated to control and reduce the microbial growth of chiken meat. However sAEA with low levels of free clorine were not studied. In the current study, the stability of sAEA with low free clorine concentration and its application in chicken breast meat was assessed by evolution of microorganisms and lipid oxidation during storage. To acess the stability, sAEA with pH 6 and 10 mg/L of FCC was diluted for 2 and 5 mg/L and its oxidation-redution potential (ORP), pH and FCC were determining over 5 days of storage at 4 °C. The sAEA was applied in chicken breast meat by immersion and by the combination of spray and immersion to evaluate the shelf-life during storad 4 °C for 6 days. The shelf-life was evaluated by mesophilic and psychotrophic bacteria growth, pH value and lipi oxidation by TBARS levels. All of sAEA maintained their ORP, pH and FCC characteristics during the storage. The chicken breast meat showed varied initial number of microorganisms, which influence the redution promoted by sAEA treatment. Higher mesophilic bacteria number show lower redution by sAEA. In general, sAEA was more effective in reducing mesophilic than psychotrophic bacteria after treatment application. The chicken breast pH were not affected by sAEFA. However, anyone sAEA application mode increase the shelf-life of chicken breast meat. TBARS values were confuse, and further studies are necessary to clarify the sAEA action mechanism front lipid oxidation. | Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq | Devido à sua composição, a carne de frango pode sofrer rápida deterioração pela presença de microrganismos, sendo que o tipo e número de microrganismos definem a qualidade higiênico-sanitária do produto. O uso da água eletrolisada fracamente ácida (AEFA) com alta concentração de cloro livre tem sido investigado na redução da carga microbiana de frangos de corte, mas com baixa concentração não se tem relatos. Esse trabalho teve como objetivo avaliar a estabilidade e método de aplicação da AEFA com 2, 5 e 10 mg/L de cloro livre em peitos de frango, e acompanhar a evolução dos microrganismos deteriorantes e a oxidação dos lipídios durante o armazenamento refrigerado. Estudou-se a estabilidade da AEFA com pH 6,0 com 2, 5 e 10 mg/L de cloro livre, determinando o potencial de oxirredução (POR), pH e concentração de cloro livre (CCL) ao longo de 5 dias de armazenamento a 4 °C. As AEFAs foram aplicadas nos peitos de frango pelo método de imersão e pela combinação de spray e imersão para avaliação da vida-útil de peitos de frango armazenados a 4 °C durante 6 dias. A vida-útil foi acompanhada pelo crescimento de bactérias mesófilas e psicrotróficas, valor de pH e a evolução da oxidação lipídica foi acompanhada pelos níveis de TBARS. As AEFAs elaboradas mantiveram suas características de POR, pH e CCL durante o período de armazenamento estudado. Os peitos de frango apresentaram número inicial de microrganismos variado, o que influenciou na redução promovida pelo tratamento com AEFA, sendo que quanto maior a carga de bactérias mesófilas, menor a percentagem de redução promovida pela AEFA. Notou-se, em todos os métodos de aplicação, que a AEFA foi mais efetiva frente às bactérias mesófilas do que as psicrotróficas logo após a aplicação dos tratamentos, e que o pH dos peitos de frango não foram influenciados pela aplicação da AEFA. Entretanto, os diferentes tratamentos de AEFA aplicados não aumentaram o tempo de vida-útil dos peitos de frango, pois apresentaram carga microbiológica e pH considerados impróprios para o consumo no sexto dia de armazenamento. Mais estudos são necessários para esclarecer melhor o mecanismo de ação da AEFA frente às reações de oxidação lipídica
Afficher plus [+] Moins [-]PUMPING WATER IN RURAL AREAS USING A HYDRAULIC RAM LOW COST | BOMBEAMENTO DE ÁGUA NO MEIO RURAL UTILIZANDO UM CARNEIRO HIDRÁLICO DE BAIXO CUSTO Texte intégral
2013
Costa, Niedja Bezerra | Silva, Raphael Pereira | Silva, Wilson Araújo da
ABSTRACT: The recent conventional energy crisis has caused the exploitation of alternative energy sources to meet domestic uses, industrial and agricultural. The hydraulic ram or hydraulic ram is a simple machine that has features and generating tool. The energy source is the height of fall of water that, in general, is produced artificially by a small dam. The pumping of water using ram pumps is widely used in many properties, especially where electricity is scarce or no inexistent. The methodology used in constructing the equipment complies with CERPCH/2002. Based on these results we can conclude that the equipment represents an alternative option of pumping water in rural areas to small farmers in regions devoid of electricity. Assembly costs compared with conventional ram compatible with the Nº1 was below 20%. KEY-WORDS: irrigation, sustainability, water hammer. | RESUMO: A recente crise da energia convencional tem ocasionado a exploração de fontes alternativas de energias para suprir usos doméstico, industrial e agrícola. O carneiro hidráulico ou aríete hidráulico é uma máquina simples que possui características geratriz e operatriz. A fonte de energia é a altura de queda d’água que, em geral, é produzida artificialmente por meio de pequena barragem. O bombeamento de água utilizando carneiro hidráulico é amplamente empregado em muitas propriedades, principalmente onde a energia elétrica é escassa ou inexistente. A metodologia utilizada na construção do equipamento está de acordo com CERPCH/2002. Com base nos resultados encontrados pode-se concluir que o equipamento representa uma opção alternativa de bombeamento de água no meio rural para pequenos produtores em regiões desprovidas de energia elétrica. Os custos de montagem, comparado com o carneiro convencional compatível com o N°1 foi abaixo de 20%. PALAVRAS-CHAVE: golpe de aríete, irrigação, sustentabilidade.
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