978 resultados para Air pollution monitoring


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The isoprene degradation mechanism included in version 3 of the Master Chemical Mechanism (MCM v3) has been evaluated and refined, using the Statewide Air Pollution Research Center (SAPRC) environmental chamber datasets on the photo-oxidation of isoprene and its degradation products, methacrolein (MACR) and methylvinyl ketone (MVK). Prior to this, the MCM v3 butane degradation chemistry was also evaluated using chamber data on the photo-oxidation of butane, and its degradation products, methylethyl ketone (MEK), acetaldehyde (CH3CHO) and formaldehyde (HCHO), in conjunction with an initial evaluation of the chamber-dependent auxiliary mechanisms for the series of relevant chambers. The MCM v3 mechanisms for both isoprene and butane generally performed well and were found to provide an acceptable reaction framework for describing the NOx-photo-oxidation experiments on the above systems, although a number of parameter modifications and refinements were identified which resulted in an improved performance. All these relate to the magnitude of sources of free radicals from organic chemical process, such as carbonyl photolysis rates and the yields of radicals from the reactions of O3 with unsaturated oxygenates, and specific recommendations are made for refinements. In addition to this, it was necessary to include a representation of the reactions of O(3P) with isoprene, MACR and MVK (which were not previously treated in MCM v3), and conclusions are drawn concerning the required extent of free radical formation from these reactions. Throughout the study, the performance of MCM v3 was also compared with that of the SAPRC-99 mechanism, which was developed and optimized in conjunction with the chamber datasets.

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The representation of alkene degradation in version 3 of the Master Chemical Mechanism (MCM v3) has been evaluated, using environmental chamber data on the photo-oxidation of ethene, propene, 1-butene and 1-hexene in the presence of NOx, from up to five chambers at the Statewide Air Pollution Research Center (SAPRC) at the University of California. As part of this evaluation, it was necessary to include a representation of the reactions of the alkenes with O(3P), which are significant under chamber conditions but generally insignificant under atmospheric conditions. The simulations for the ethene and propene systems, in particular, were found to be sensitive to the branching ratios assigned to molecular and free radical forming pathways of the O(3P) reactions, with the extent of radical formation required for proper fitting of the model to the chamber data being substantially lower than the reported consensus. With this constraint, the MCM v3 mechanisms for ethene and propene generally performed well. The sensitivity of the simulations to the parameters applied to a series of other radical sources and sink reactions (radical formation from the alkene ozonolysis reactions and product carbonyl photolysis; radical removal from the reaction of OH with NO2 and β-hydroxynitrate formation) were also considered, and the implications of these results are discussed. Evaluation of the MCM v3 1-butene and 1-hexene degradation mechanisms, using a more limited dataset from only one chamber, was found to be inconclusive. The results of sensitivity studies demonstrate that it is impossible to reconcile the simulated and observed formation of ozone in these systems for ranges of parameter values which can currently be justified on the basis of the literature. As a result of this work, gaps and uncertainties in the kinetic, mechanistic and chamber database are identified and discussed, in relation to both tropospheric chemistry and chemistry important under chamber conditions which may compromise the evaluation procedure, and recommendations are made for future experimental studies. Throughout the study, the performance of the MCM v3 chemistry was also simultaneously compared with that of the corresponding chemistry in the SAPRC-99 mechanism, which was developed and optimized in conjunction with the chamber datasets.

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Many South Carolina residents are concerned about indoor mold after severe weather events. DHEC has compiled this informational handout with recommendations to guide decisions regarding mold in homes and workplaces.

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The South Carolina Department of Health and Environmental Control has declared an air quality alert day for fine particulates, caused by smoke from widespread forest fires. This sheet gives seven tips for protecting yourself from wildfire smoke.

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The Mt. Bachelor Observatory (MBO) is a high altitude atmospheric research station that is located at the Mt. Bachelor ski area in Central Oregon. The observatory was started by Prof. Dan Jaffe in 2004. Over this time, his time at UW has made observations of ozone, carbon monoxide, mercury, nitrogen oxides, particulate matter and other atmospheric constituents. The data for 2015 are reported in this dataset. MBO coordinates (summit building): Latitude: 43.9775 N Longitude: 121.6861 W Elevation: 2.74 km asl

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La presente investigación tiene como objetivo principal, explicar la influencia de los ODM del PNUD en la implementación de políticas públicas medioambientales de Tailandia en el periodo del 2000 al 2013, basado en la teoría de los complejos de socialización y la transferencia de normas que implican un buen comportamiento medioambiental. De esta manera, demostrar que los agentes socializadores han cumplido un papel fundamental para la implementación de políticas públicas en Tailandia en su interés por cumplir con sus compromisos internacionales. Esta monografía utilizara un método cualitativo, desde el análisis de las fuentes primarias y secundarias, realizando especial énfasis en la teoría de complejos de socialización que permita un análisis descriptivo y explicativo del fenómeno.

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La presente investigación tiene como objetivo principal, explicar la influencia de los ODM del PNUD en la implementación de políticas públicas medioambientales de Tailandia en el periodo del 2000 al 2013, basado en la teoría de los complejos de socialización y la transferencia de normas que implican un buen comportamiento medioambiental. De esta manera, demostrar que los agentes socializadores han cumplido un papel fundamental para la implementación de políticas públicas en Tailandia en su interés por cumplir con sus compromisos internacionales. Esta monografía utilizara un método cualitativo, desde el análisis de las fuentes primarias y secundarias, realizando especial énfasis en la teoría de complejos de socialización que permita un análisis descriptivo y explicativo del fenómeno.

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Introducción El material particulado son partículas sólidas y líquidas emitidas al aire, las cuales pueden generar diferentes alteraciones en la salud, variando desde cuadros respiratorios alérgicos, a episodios asmáticos, dermatitis o inclusive llegar a facilitar la génesis de enfermedades de tipo neoplásico. Estos pueden tener origen natural e industrial, encontrandose en diferentes actividades económicas. Objetivo Evaluar la exposición laboral a material particulado en empresas pertenecientes a diferentes sectores económicos afiliadas a una ARL en Colombia, en el periodo comprendido entre 2011 al 2014 Metodología Es un estudio de corte transversal, analizando una base de datos de 257 empresas con 1108 mediciones de material particulado, recolectados entre 2011 – 2014. Las variables usadas fueron: región, actividad económica, área, oficio, tiempo de exposición y concentración de material particulado. Se realizó distribuciones de frecuencia, medidas de tendencia central y de dispersión. Se evaluaron las diferencias de las distribuciones de los tiempos de exposición y el porcentaje de exposición entre los grupos con y sin riesgo (los que sobrepasaban o no los límites permisibles), con la prueba asintótica no paramétrica de Mann Whitney. Resultados Las principales mediciones ambientales en las empresas fueron en la industria química con un 31%, siendo 2 de cada 3 datos pertenecientes a la región andina, las cuales tienen como principales contaminantes químicos las partículas no fraccionadas con el 70,9%. Respecto a las concentraciones ambientales de material particulado en las empresas participantes, se encontró un promedio de 1,72 mg/m3 ± 3,613, con una mediana de 0,480 mg/m3 y un coeficiente de variación de 210,05%. El 2,9% sobrepasaron los valores límites establecidos por la ACGIH (American Conference of Governmental Industrial Hygienists) y el 92,5% según los límites de la EPA (Agencia de Protección del Ambiente), presentando mayor riesgo en el personal operativo con 93,3% (p= 0,002). Conclusión El riesgo según los límites establecidos por la ACGIH para las mediciones realizadas en Colombia fue bajo, aunque al utilizar los parámetros de la EPA, el riesgo fue alto, por lo cual se requiere hacer un seguimiento específico a estas empresas y fomentar la implementación del sistema de gestión en seguridad y salud en el trabajo.

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Since black carbon concentrations are useful to reveal changes in anthropogenic activities, measurements taken from 2007 to 2015 in a Portuguese city are used to assess to which extent the ambient air was impacted by the economic crisis. The average black carbon concentrations are representative of an urban area of small size (1.3 ± 1.3 μg m−3). The highest concentrations are observed in the heating season, being biomass combustion one of the causes for the high values. The daily cycle of black carbon concentrations presents both morning and evening peaks, mainly due to road traffic and, in the heating season, to domestic heating as well. The yearly averaged black carbon mass concentrations decreased 33 % from 2007 to 2015, possibly due to a combination of the economic recession and environmental legislation. The reduction in road traffic led to a decrease in the daily morning peak from 2007 to 2015. This reduction was not followed by a decrease in the evening peak, explained by an increase in biomass burning. Biomass is the cheapest heating fuel in Portugal, and its consumption increased in the aftermath of the economic crisis. The use of bioenergy is an alternative to fossil fuels and presents many advantages. However, energy policies should discourage inefficient biomass burning and promote better ways of exploiting the available energy resources and emission air pollution mitigation strategies.

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Nowadays, the spreading of the air pollution crisis enhanced by greenhouse gases emission is leading to the worsening of the global warming. In this context, the transportation sector plays a vital role, since it is responsible for a large part of carbon dioxide production. In order to address these issues, the present thesis deals with the development of advanced control strategies for the energy efficiency optimization of plug-in hybrid electric vehicles (PHEVs), supported by the prediction of future working conditions of the powertrain. In particular, a Dynamic Programming algorithm has been developed for the combined optimization of vehicle energy and battery thermal management. At this aim, the battery temperature and the battery cooling circuit control signal have been considered as an additional state and control variables, respectively. Moreover, an adaptive equivalent consumption minimization strategy (A-ECMS) has been modified to handle zero-emission zones, where engine propulsion is not allowed. Navigation data represent an essential element in the achievement of these tasks. With this aim, a novel simulation and testing environment has been developed during the PhD research activity, as an effective tool to retrieve routing information from map service providers via vehicle-to-everything connectivity. Comparisons between the developed and the reference strategies are made, as well, in order to assess their impact on the vehicle energy consumption. All the activities presented in this doctoral dissertation have been carried out at the Green Mobility Research Lab} (GMRL), a research center resulting from the partnership between the University of Bologna and FEV Italia s.r.l., which represents the industrial partner of the research project.

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Nowadays, the spreading of the air pollution crisis enhanced by greenhouse gases emission is leading to the worsening of global warming. Recently, several metropolitan cities introduced Zero-Emissions Zones where the use of the Internal Combustion Engine is forbidden to reduce localized pollutants emissions. This is particularly problematic for Plug-in Hybrid Electric Vehicles, which usually work in depleting mode. In order to address these issues, the present thesis presents a viable solution by exploiting vehicular connectivity to retrieve navigation data of the urban event along a selected route. The battery energy needed, in the form of a minimum State of Charge (SoC), is calculated by a Speed Profile Prediction algorithm and a Backward Vehicle Model. That value is then fed to both a Rule-Based Strategy, developed specifically for this application, and an Adaptive Equivalent Consumption Minimization Strategy (A-ECMS). The effectiveness of this approach has been tested with a Connected Hardware-in-the-Loop (C-HiL) on a driving cycle measured on-road, stimulating the predictions with multiple re-routings. However, even if hybrid electric vehicles have been recognized as a valid solution in response to increasingly tight regulations, the reduced engine load and the repeated engine starts and stops may reduce substantially the temperature of the exhaust after-treatment system (EATS), leading to relevant issues related to pollutant emission control. In this context, electrically heated catalysts (EHCs) represent a promising solution to ensure high pollutant conversion efficiency without affecting engine efficiency and performance. This work aims at studying the advantages provided by the introduction of a predictive EHC control function for a light-duty Diesel plug-in hybrid electric vehicle (PHEV) equipped with a Euro 7-oriented EATS. Based on the knowledge of future driving scenarios provided by vehicular connectivity, engine first start can be predicted and therefore an EATS pre-heating phase can be planned.

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With the development of the economy and society, air pollution has posed a huge threat to public health around the world, especially to people who live in urban areas. Typically, urban development patterns can be roughly divided into compact cities and urban sprawl. In recent years, the relationship between urban form and air quality (especially PM2.5) is gaining more and more attention from urban planners, environmentalists, and governments. This study is focusing on The New York metropolitan area and Shanghai city, which are both megacities but with different urban spatial forms. For both study areas,there are five main variables to measure the urban form metrics, naming Population Density, Artificial Land Area Per Ten Thousand People, Road Density, Green Land Area Ratio and Artificial Land Area Ratio. In addition, considering the impact of economic activities and public transportation, GDP per capita, Number of bus stop and Number of subway station are used as control variables. Based on the results of regression, a megacity like the New York metropolitan area with urban sprawl shows a low spatial correlation on PM2.5 concentration. Meanwhile, almost all the spatial form indicators effect on PM2.5 concentration is not significant. However, a compact megacity like Shanghai shows a diametrically opposite result. Urban form, especially population density, has a strong relationship with PM2.5 concentration. It can be predicted that a reduction in population density would lead to significant improvements on decrease the PM2.5 concentration in Shanghai. Meanwhile, increasing the ratio of green land and construction area per capita will get a positive influence on reducing PM2.5 concentration as well. Road density is not a significant factor for a megacity in both two urban forms. The way and type of energy used by vehicles on megacities maybe more critical.

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Esta tesis examina las implicaciones técnicas, políticas y espaciales del aire urbano, y en concreto, de la calidad del aire, para tenerlo en cuenta desde una perspectiva arquitectónica. En oposición a formas de entender el aire como un vacío o como una metáfora, este proyecto propone abordarlo desde un acercamiento material y tecnológico, trayendo el entorno al primer plano y reconociendo sus múltiples agencias. Debido a la escasa bibliografía detectada en el campo de la arquitectura, el objetivo es construir un marco teórico-analítico para considerar el aire urbano. Para ello el trabajo construye Aeropolis, una metáfora heurística que describe el ensamblaje sociotecnico de la ciudad. Situada en la intersección de determinadas ramas de la filosofía de la cultura, los estudios sobre ciencia y tecnología y estudios feministas de la ciencia este nuevo paisaje conceptual ofrece una metodología y herramientas para abordar el objeto de estudio desde distintos ángulos. Estas herramientas metodológicas han sido desarrolladas en el contexto específico de Madrid, ciudad muy contaminada cuyo aire ha sido objeto de controversias políticas y sociales, y donde las políticas y tecnologías para reducir sus niveles no han sido exitosas. Para encontrar una implicación alternativa con el aire esta tesis propone un método de investigación de agentes invisibles a partir del análisis de sus dispositivos epistémicos. Se centra, en concreto, en los instrumentos que miden, visualizan y comunican la calidad del aire, proponiendo que no sólo lo representan, sino que son también instrumentos que diseñan el aire y la ciudad. La noción de “sensing” (en castellano medir y sentir) es expandida, reconociendo distintas prácticas que reconstruyen el aire de Madrid. El resultado de esta estrategia no es sólo la ampliación de los espacios desde los que relacionarnos con el aire, sino también la legitimación de prácticas existentes fuera de contextos científicos y administrativos, como por ejemplo prácticas relacionadas con el cuerpo, así como la redistribución de agencias entre más actores. Así, esta tesis trata sobre toxicidad, la Unión Europea, producción colaborativa, modelos de computación, dolores de cabeza, kits DIY, gases, cuerpos humanos, salas de control, sangre o políticos, entre otros. Los dispositivos que sirven de datos empíricos sirven como un ejemplo excepcional para investigar infraestructuras digitales, permitiendo desafiar nociones sobre Ciudades Inteligentes. La tesis pone especial atención en los efectos del aire en el espacio público, reconociendo los procesos de invisibilización que han sufrido sus infraestructuras de monitorización. Para terminar se exponen líneas de trabajo y oportunidades para la arquitectura y el diseño urbano a través de nuevas relaciones entre infraestructuras urbanas, el medio construido, espacios domésticos y públicos y humanos y no humanos, para crear nuevas ecologías políticas urbanas (queer). ABSTRACT This thesis examines the technical, political and spatial implications of urban air, and more specifically "air quality", in order to consider it from an architectural perspective. In opposition to understandings of the air either as a void or as a metaphor, this project proposes to inspect it from a material and technical approach, bringing the background to the fore and acknowledging its multiple agencies. Due to the scarce bibliography within the architectural field, its first aim is to construct a theoretical and analytical framework from which to consider urban air. For this purpose, the work attempts the construction of Aeropolis, a heuristic metaphor that describes the city's aero socio-material assemblage. Located at the intersection of certain currents in cultural philosophy, science and technology studies as well as feminist studies in technoscience, this framework enables a methodology and toolset to be extracted in order to approach the subject matter from different angles. The methodological tools stemming from this purpose-built framework were put to the test in a specific case study: Madrid, a highly polluted city whose air has been subject to political and social controversies, and where no effective policies or technologies have been successful in reducing its levels of pollution. In order to engage with the air, the thesis suggests a method for researching invisible agents by examining the epistemic devices involved. It locates and focuses on the instruments that sense, visualise and communicate urban air, claiming that they do not only represent it, but are also instruments that design the air and the city. The notion of "sensing" is then expanded by recognising different practices which enact the air in Madrid. The work claims that the result of this is not only the opening up of spaces for engagement but also the legitimisation of existing practices outside science and policymaking environments, such as embodied practices, as well as the redistribution of agency among more actors. So this is a thesis about toxicity, the European Union, collaborative production, scientific computational models, headaches, DIY kits, gases, human bodies, control rooms, blood, or politicians, among many others. The devices found throughout the work serve as an exceptional substrate for an investigation of digital infrastructures, enabling to challenge Smart City tropes. There is special attention paid to the effects of the air on the public space, acknowledging the silencing processes these infrastructures have been subjected to. Finally there is an outline of the opportunities arising for architecture and urban design when taking the air into account, to create new (queer) urban political ecologies between the air, urban infrastructures, the built environment, public and domestic spaces, and humans and more than humans.

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High levels of marine salt deposition present in coastal areas have a relevant effect on road runoff characteristics. This study assesses this effect with the purpose of identifying the relationships between monitored water quality parameters and intrinsic site variables. To achieve this objective, an extensive monitoring program was conducted on a Portuguese coastal highway. The study included 30 rainfall events, in different weather, traffic, and salt deposition conditions. The evaluations of various water quality parameters were carried out in over 200 samples. In addition, the meteorological, hydrological, and traffic parameters were continuously measured. The salt deposition rates were determined by means of a wet candle device, which is an innovative feature of the monitoring program. The relation between road runoff pollutants and independent variables associated with weather, traffic, and salt deposition conditions was assessed. Significant correlations among pollutants were observed. A high salinity concentration and its influence on the road runoff were confirmed. Furthermore, the concentrations of the most relevant pollutants seemed to be very dependent on some meteorological variables, particularly the duration of the antecedent dry period prior to each rainfall event and the average wind speed.

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We analyze a model where firms chose a production technology which, together with some random event, determines the final emission level. We consider the coexistence of two alternative technologies: a "clean" technology, and a "dirty" technology. The environmental regulation is based on taxes over reported emissions, and on penalties over unreported emissions. We show that the optimal inspection policy is a cut-off strategy, for several scenarios concerning the observability of the adoption of the clean technology and the cost of adopting it. We also show that the optimal inspection policy induces the firm to adopt the clean technology if the adoption cost is not too high, but the cost levels for which the firm adopts it depend on the scenario.