974 resultados para Ultrafine Particles, Laser Printer, Indoor Air Quality, Aerosol Formation
Resumo:
El estudio se centra en el sector residencial de la ciudad de Cuenca, Ecuador. El objetivo es determinar hasta donde se puede reducir el consumo de energía a la vez que se obtengan óptimas condiciones de confort, estableciendo un indicador de eficiencia energética. Para ello se determina la demanda de energía eléctrica y los factores principales de consumo, mediante una metodología de investigación mixta tanto cualitativa como cuantitativa, pues el consumo energético se ve influenciado por diferentes elementos como la eficiencia de los equipos, diseño y hábitos de uso de los habitantes, entre otros. Se realizan encuestas a una muestra de 280 hogares del sector residencial de Cuenca y por otro lado se mide el consumo y calidad lumínica del ambiente interior de 6 viviendas mediante equipos, simulaciones y encuestas. Posteriormente se analizan los resultados obtenidos y se los compara con los estándares de eficiencia nacional e internacional, se proponen estrategias básicas para la reducción del consumo de energía eléctrica y finalmente el estudio define una clasificación de indicadores de consumo mínimo.
Resumo:
Carbon Monoxide (CO) and Ozone (O3) are considered to be one of the most important atmospheric pollutants in the troposphere with both having significant effects on human health. Both are included in the U.S. E.P.A list of criteria pollutants. CO is primarily emitted in the source region whereas O3 can be formed near the source, during transport of the pollution plumes containing O3 precursors or in a receptor region as the plumes subside. The long chemical lifetimes of both CO and O3 enable them to be transported over long distances. This transport is important on continental scales as well, commonly referred to as inter-continental transport and affects the concentrations of both CO and O3 in downwind receptor regions, thereby having significant implications for their air quality standards. Over the period 2001-2011, there have been decreases in the anthropogenic emissions of CO and NOx in North America and Europe whereas the emissions over Asia have increased. How these emission trends have affected concentrations at remote sites located downwind of these continents is an important question. The PICO-NARE observatory located on the Pico Mountain in Azores, Portugal is frequently impacted by North American pollution outflow (both anthropogenic and biomass burning) and is a unique site to investigate long range transport from North America. This study uses in-situ observations of CO and O3 for the period 2001-2011 at PICO-NARE coupled with output from the full chemistry (with normal and fixed anthropogenic emissions) and tagged CO simulations in GEOS-Chem, a global 3-D chemical transport model of atmospheric composition driven by meteorological input from the Goddard Earth Observing System (GEOS) of the NASA Global Modeling and Assimilation Office, to determine and interpret the trends in CO and O3 concentrations over the past decade. These trends would be useful in ascertaining the impacts emission reductions in the United States have had over Pico and in general over the North Atlantic. A regression model with sinusoidal functions and a linear trend term was fit to the in-situ observations and the GEOS-Chem output for CO and O3 at Pico respectively. The regression model yielded decreasing trends for CO and O3 with the observations (-0.314 ppbv/year & -0.208 ppbv/year respectively) and the full chemistry simulation with normal emissions (-0.343 ppbv/year & -0.526 ppbv/year respectively). Based on analysis of the results from the full chemistry simulation with fixed anthropogenic emissions and the tagged CO simulation it was concluded that the decreasing trends in CO were a consequence of the anthropogenic emission changes in regions such as USA and Asia. The emission reductions in USA are countered by Asian increases but the former have a greater impact resulting in decreasing trends for CO at PICO-NARE. For O3 however, it is the increase in water vapor content (which increases O3 destruction) along the pathways of transport from North America to PICO-NARE as well as around the site that has resulted in decreasing trends over this period. This decrease is offset by increase in O3 concentrations due to anthropogenic influence which could be due to increasing Asian emissions of O3 precursors as these emissions have decreased over the US. However, the anthropogenic influence does not change the final direction of the trend. It can thus be concluded that CO and O3 concentrations at PICO-NARE have decreased over 2001-2011.
Resumo:
Light non-aqueous phase liquid (LNAPL) sources can pose a significant threat to indoor air through vapour intrusion (VI). Most conceptual and numerical models of VI assume that the transport of volatile organic compounds (VOCs) is a diffusion-limited process. Recently, alternate conditions have been identified that could lead to faster transport, including the presence of preferential pathways and methanogenic gas production. In this study, an additional mechanism that could lead to faster transport was investigated: bubble-facilitated VOC transport from LNAPL smear zones. A laboratory investigation was preformed using pentane in one-dimensional laboratory columns and two-dimensional visualization experiments. Results of the column experiments showed that average VOC mass fluxes in the bubble-facilitated columns were over two orders of magnitude greater than in the diffusion-limited columns. In addition, the flux signal was intermittent, consistent with expectations of bubble-facilitated transport as bubbles expand, mobilize and are released to the vadose zone at various times during the test. The results from the visualization experiments showed gas fingers growing and mobilizing over time, which supports the findings of the column experiments. In conclusion, these results demonstrate the potential for bubble-facilitated VOC transport to affect mass transfer in LNAPL smear zones, and lead to increased indoor air concentrations by VI.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
Resumo:
The “Compass E-Newsletter” is published quarterly by the South Carolina Department of Health and Environmental Control and is compiled by the Office of Solid Waste Reduction and Recycling to provide environmental information from the agency.
