Air concentrations

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  • Air pollution has been a major transboundary problem and a matter of global concern for decades. High concentrations of different air pollutants are particularly harmful to large cities residents, where numerous anthropogenic activities strongly influence the quality of air. Although there are many books on the subject, the one in front of you will hopefully fulfill some of the gaps in the area of air quality monitoring and modeling, and be of help to graduate students, professionals and researchers....

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  • This book on Environmental Technology takes a look at issues such as air, soil and noise pollution problems, environmental quality assessment, monitoring, modelling and risk as- sessment, environmental health impact assessment, environmental management and envi- ronmental technology development. It represents institutional arrangements, financial mechanisms and some sustainable technologies. The user can always count on finding both introductory material and more specific material based on national interests and problems.

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  • Human beings need to breathe oxygen diluted in certain quantity of inert gas for living. In the atmosphere, there is a gas mixture of, mainly, oxygen and nitrogen, in appropriate proportions. However, the air also contains other gases, vapours and aerosols that humans incorporate when breathing and whose composition and concentration vary spatially. Some of these are physiologically inert. Air pollution has become a problem of major concern in the last few decades as it has caused negative effects on human health, nature and properties....

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  • Air pollution has always been a trans-boundary environmental problem and a matter of global concern for past many years. High concentrations of air pollutants due to numerous anthropogenic activities influence the air quality. There are many books on this subject, but the one in front of you will probably help in filling the gaps existing in the area of air quality monitoring, modelling, exposure, health and control, and can be of great help to graduate students professionals and researchers.

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  • Modern urban Air Pollution Stagnant air Continuing emissions "summer" (photochemical) smog: NO, NO2, CxHy, UV-rad: == O3 (reactions worked out on blackboard) Winter (cold weather) smog: fine or ultra-fine particles == health effects Mixture is different in different cities Traffic important source Toxicological mechanism still unknown Health effects even at low concentrations (from 40 mg/m3?)

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  • although concentrations of sulfur dioxide and black smoke have been significantly decreasing worldwide in the last ten years [20], the present air concentrations in the city of niš are still an important threat to childrens health. It is difficult to determine whether one of the mea- sured pollutants, alone or in combination, was responsible for the observed health effects in children. It is also less clear which pollutants are most responsible for anemia of children. little is known about the possible adverse ef- fects of exposure to complex mixtures of chemicals.

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  • During the past several decades, air quality in homes and office buildings has become a matter of increasing concern. Indoor air concentrations of volatile organic compounds are often significantly higher than outside due to VOC emissions from building materials, furnishings, and occupant’s activities. This problem was exacerbated following the energy crisis in the 1970s as homeowners and builders improved the energy efficiency of their buildings by decreasing air exchange rates.

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  • Risk assessment is an inexact science. Successful risk assessment practitioners rely heavily on extensive and well-documented databases.

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  • The present science book "Application of Solar Energy" is edited by Professor R. D. Rugescu in the series on Solar Power and consists of 7 chapters that begin with the proof of the high thermal efficiency of the gravitational draught through concentrated solar heating. It continues with novel technologies of producing organic fuels through solar heating, new types of photovoltaic cells, long term use of thermal solar power plants, the efficiency of thermal storage and applications in Niger of the Solar power.

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  • Since the Second World War, and especially since the publication of Rachel Carson’s Silent Spring in 1962, there has been growing concern about contamination of the environment by “man-made” chemicals. These chemicals may be present in industrial and municipal effluents, in consumer or commercial products, in mine tailings, in petroleum products, and in gaseous emissions. Some chemicals such as pesticides may be specifically designed to kill biota present in natural or agricultural ecosystems. They may be organic, inorganic, metallic, or radioactive in nature.

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  • 16 Membrane Separation 16.1 OVERVIEW Membrane separation has developed into an important technology for separating VOCs and other gaseous air pollutants from gas streams during the past 15 years. The first commercial application was installed in 1990, and more than 50 systems have been installed in the chemical process industry worldwide.1 The technology utilizes a polymeric membrane that is more permeable to condensable organic vapors, such as C3+ hydrocarbons and aromatics, than it is to noncondensable gases such as methane, ethane, nitrogen, and hydrogen.

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  • Concentrations of VOCs generated indoors may be presumed to decrease proportionally in response to increases in house ventilation. This has been documented in a new, unoccupied house for those VOCs with the highest vapor pressures (Hodgson et al., 2000). However, within chemical classes, the effectiveness of ventilation for reducing concentrations generally decreases with decreasing volatility (ibid.).

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  • When planning how to reduce the threat of global warming and how to adapt to it, a very important piece of information is how intense the change will be. That implies estimating the trends of future concentrations of greenhouse gasses, and the potential future changes in temperature, precipitation, storm events and other climatic variables. These predictions are important not only to estimate the magnitude of the changes, but also to determine the uncertainty surrounding them.

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  • Lichens have been used to study air pollution chemistry in national parks and forests since the 1980s (Figures 1 and 2). There have also been a few lichen studies on national wildlife refuges. Most of the studies have been floristic studies, reports of baseline concentrations of elements in lichen tissues and, occasionally, trends in these concentrations. Figure 1 shows park and refuge locations with tissue chemistry data. USGS Biological Resources Division maintains a web site listing lichens known from each of the national parks shown on the map (http://www.ies.wisc.

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  • The European Union has developed the draft of a “Working document on sludge” (EU 2000), to promote the use of sewage sludge in agriculture while improving the safety and harmonize quality standards. It proposes limit values for concentrations of heavy metals and organic compounds that should restrict the use of sewage sludge in agriculture if the limits are exceeded and provides suggestions for good practice in treatment and agricultural use.

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  • Edwards et al (2006) report indoor air quality monitoring in nearly 400 households in the three provinces of Hubei, Shaanxi, and Zhejiang in 2002-2003. Great care was taken to select homes that reflect the diversity of fuels and stove technology and stove performance in China. PM4 concentrations in 75 percent of kitchens and 73 percent of living rooms during the winter - and 48 percent of kitchens and 46 percent of living rooms during the summer - exceeded the national indoor air quality PM10 standard of 150 ug/m3 for a 24 hour average. If PM10...

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  • Patterns of particle emission are different from those of the other pollutants included in the first phase of the EU Framework Directive because of their extreme diversity of origin and source, both primary and secondary, natural and anthropogenic, and there are significant differences in levels between Member States and regions within states. The limited amount of reliable PM10 data makes it difficult to establish a comprehensive overview of PM10 concentrations and trends in Member States.

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  • The available data does, however, suggest that present PM10 values exceed the recommended limit values in the majority of Member States. In future projections, planned actions should be taken into consideration. These include the SOx and NOx Protocols within UNECE and the Auto-Oil programme. Abatement policies for other pollutants will also have an impact.

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  • Several attempts have been made to analyze the impacts of air pollution on wildlife . More recently, research for WWF has assessed the impacts on wildlife through a literature survey which identified effects on 1,300 species, including 11 mammals, 29 birds, 10 amphibians, 398 higher plants, 305 fungi, 238 lichens and 65 invertebrates, providing the most detailed survey to date 7 . In general, the studies have concentrated on either specific ecosystems, or individual groups of plants and animals.

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  • Some results of indoor particulate (PM) concentrations measurements in relation to type of stove and fuel from Latin-America are presented in table 2.1. The improved stoves, such as the plancha, produce PM 2.5 or PM 3.5 levels that are often only 20 percent of concentration levels from an open fire, and are even found to be less than 10 percent of that of an open fire in a study in Guatemala by McCracken and Smith (1998). The reduction in PM 2.5 seems to be even larger than reductions in PM 10. However the concentration levels...

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