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Pontiggia M - - 2009
Nowadays, thanks to the increasing CPU power the use of Computational Fluid Dynamics (CFD) is rapidly imposing also in the industrial risk assessment area, replacing integral models when particular situations, such as those involving complex terrains or large obstacles, are involved. Nevertheless, commercial CFD codes usually do not provide specific ...
Su Jason G JG Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, - - 2009
Land use regression (LUR) has emerged as an effective means of estimating exposure to air pollution in epidemiological studies. We created the first LUR models of nitric oxide (NO), nitrogen dioxide (NO2) and nitrogen oxides (NOX) for the complex megalopolis of Los Angeles (LA), California. Two-hundred and one sampling sites ...
Choi Jungsoon - - 2009
Fine particulate matter (PM(2.5)) is a mixture of pollutants that has been linked to serious health problems, including premature mortality. Since the chemical composition of PM(2.5) varies across space and time, the association between PM(2.5) and mortality could also change with space and season. In this work we develop and ...
Pratt Scott - - 2009
Two particle correlation data from the BNL Relativistic Heavy Ion Collider have provided detailed femtoscopic information describing pion emission. In contrast with the success of hydrodynamics in reproducing other classes of observables, these data had avoided description with hydrodynamic-based approaches. This failure has inspired the term "HBT puzzle," where HBT ...
Rodriguez Sébastien - - 2009
Clouds on Titan result from the condensation of methane and ethane and, as on other planets, are primarily structured by circulation of the atmosphere. At present, cloud activity mainly occurs in the southern (summer) hemisphere, arising near the pole and at mid-latitudes from cumulus updrafts triggered by surface heating and/or ...
Van de Vel Karen - - 2010
In this paper, we assess the status of the air quality in the Lake Baikal region which is strongly influenced by the presence of anthropogenic pollution sources. We combined the local data, with global databases, remote sensing imagery and modelling tools. This approach allows to inventorise the air-polluting sources and ...
Choi Jungsoon - - 2009
Fine particulate matter (PM(2.5)) is an atmospheric pollutant that has been linked to serious health problems, including mortality. PM(2.5) is a mixture of pollutants, and it has five main components: sulfate, nitrate, total carbonaceous mass, ammonium, and crustal material. These components have complex spatial-temporal dependency and cross dependency structures. It ...
Hoff Steven J - - 2009
This paper describes techniques used to determine airflow rate in multiple emission point applications typical of animal housing. An accurate measurement of building airflow rate is critical to accurate emission rate estimates. Animal housing facilities rely almost exclusively on ventilation to control inside climate at desired conditions. This strategy results ...
Hoff Raymond M - - 2009
The recent literature on satellite remote sensing of air quality is reviewed. 2009 is the 50th anniversary of the first satellite atmospheric observations. For the first 40 of those years, atmospheric composition measurements, meteorology, and atmospheric structure and dynamics dominated the missions launched. Since 1995, 42 instruments relevant to air ...
Henry Ronald - - 2009
As described in this paper, nonparametric wind regression is a source-to-receptor source apportionment model that can be used to identify and quantify the impact of possible source regions of pollutants as defined by wind direction sectors. It is described in detail with an example of its application to SO2 data ...
Fulton Larry - - 2009
In this study, we evaluate rules of allocation and planning factors that have an effect on requirements for Army air ambulance companies. The Army uses rules of allocation in scenarios drawn from strategic planning documents to determine how many units of each type are required. Army planners use these rules ...
Wang Sheng-Wei - - 2009
This study presents the Individual Based Exposure Modeling (IBEM) application of MENTOR (Modeling ENvironment for TOtal Risk studies) in a hot spot area, where there are concentrated local sources on the scale of tens to hundreds of meters, and an urban reference area in Camden, NJ, to characterize the ambient ...
Hsu H T - - 2009
Human exposure to chloroform in indoor swimming pools has been recognized as a potential health concern. Although environmental monitoring is a useful technique to investigate chloroform concentrations in indoor swimming-pool air, in practice, the interpretations of measured data would inevitably run into difficulties due to the complex interactions among the ...
Mukerjee Shaibal - - 2009
Passive ambient air sampling for nitrogen dioxide (NO(2)) and volatile organic compounds (VOCs) was conducted at 25 school and two compliance sites in Detroit and Dearborn, Michigan, USA during the summer of 2005. Geographic Information System (GIS) data were calculated at each of 116 schools. The 25 selected schools were ...
Díaz-Robles L A - - 2009
The fine and ultra fine size of diesel particulate mater (DPM) are of great health concern and significantly contribute to the overall cancer risk. In addition, diesel particles may contribute a warming effect on the planet's climate. The composition of these particles is composed principally of elemental carbon (EC) with ...
Stylianou Mario - - 2009
We examined the existence of thresholds, cumulative effects and the homogeneity of five air pollutants on the relative risk of three mortality outcomes using data from nine major US cities using data from NMMAPS. Overall, PM(10) (usually 200-day accumulation) and ozone (3-day accumulation) were the two important predictors of outcome ...
Johnson Derek R - - 2009
Diesel engine emissions for on-road, stationary and marine applications are regulated in the United States via standards set by the Environmental Protection Agency (EPA). A major component of diesel exhaust that is difficult to reduce is nitrogen oxides (NOx). Selective catalytic reduction (SCR) has been in use for many years ...
Crawford Robert H - - 2009
In Australia, there are currently two main materials used for railway sleepers: timber (river red gum, a species of eucalypt) and reinforced concrete. Within the state of Victoria alone, there are currently seven million railway sleepers that make up the rail network. It is estimated that around two million sleepers, ...
Ghazali Nurul Adyani - - 2010
Analysis and forecasting of air quality parameters are important topics of atmospheric and environmental research today due to the health impact caused by air pollution. This study examines transformation of nitrogen dioxide (NO(2)) into ozone (O(3)) at urban environment using time series plot. Data on the concentration of environmental pollutants ...
Callén M S - - 2009
Receptor models are useful to understand the chemical and physical characteristics of air pollutants by identifying their sources and by estimating contributions of each source to receptor concentrations. In this work, three receptor models based on principal component analysis with absolute principal component scores (PCA-APCS), Unmix and positive matrix factorization ...
Zeng Gengsheng L GL Utah Center for Advanced Imaging, Department of Radiology, University of Utah, Salt Lake City, UT 84108, USA. - - 2009
It is common, even with new SPECT/CT systems, that the transmission data are truncated. This paper develops a method that obtains exact attenuation correction with truncated transmission data. The emission object (e.g., the heart) is assumed to have a finite, convex support, whose emission projections are not truncated. The transmission ...
Laner David - - 2009
Within a product system of a life-cycle assessment (LCA), solid waste landfills should be treated as processes, because they are considered to be a part of the technical system. Hence, their inputs and outputs should be included in the life-cycle inventory analysis and evaluated within the life-cycle impact assessment. The ...
Serageldin Mohamed - - 2009
Knowledge of the emission rate and release characteristics is necessary for estimating pollutant fate and transport. Because emission measurements at a facility's fence line are generally not readily available, environmental agencies in many countries are using emission factors (EFs) to indicate the quantity of certain pollutants released into the atmosphere ...
Scheffe Richard D - - 2009
A current re-engineering of the United States routine ambient monitoring networks intended to improve the balance in addressing both regulatory and scientific objectives is addressed in this paper. Key attributes of these network modifications include the addition of collocated instruments to produce multiple pollutant characterizations across a range of representative ...
Krewski Daniel - - 2009
We conducted an extended follow-up and spatial analysis of the American Cancer Society (ACS) Cancer Prevention Study II (CPS-II) cohort in order to further examine associations between long-term exposure to particulate air pollution and mortality in large U.S. cities. The current study sought to clarify outstanding scientific issues that arose ...
Bordel Sergio - - 2009
A mechanistic model describing the steady-state biodegradation of inhibitory pollutants by algal-bacterial consortia in enclosed chemostat photobioreactors was developed. The modelwasthenvalidated againstexperimentaldataonsalicylate removal by a Chlorella Sorokiniana/Ralstonia basilensis consortium cultivated without external O2 supplied in an enclosed chemostat photobioreactor under various conditions of photon flux radiation, salicylate inlet concentrations, temperatures, ...
Wuebbles Donald J - - 2009
HCFC-123 (C2HCl2F3) is used in large refrigeration systems and as a fire suppression agent blend. Like other hydrochlorofluorocarbons, production and consumption of HCFC-123 is limited under the Montreal Protocol on Substances that Deplete the Ozone Layer. The purpose of this study is to update the understanding of the current and ...
Wang Xiao Yu - - 2009
This study examines the association of long-term exposure to gaseous air pollution with cardio-respiratory mortality in Brisbane, Australia, in the period 1996-2004. The pollutant concentrations were estimated using geographical information system (GIS) techniques at the statistical local area (SLA) level. The generalized estimating equations model was used to investigate the ...
Wong Heung - - 2009
It is well known that the exposure to ambient air pollution might cause serious respiratory illnesses and that the weather conditions may also contribute to the seriousness. However, quantifying the effects of pollution and the weather condition is a difficult task due to the nonlinear nature of these impacts. The ...
Lu Chunhui - - 2009
In this paper, environmentally key properties including aqueous solubilities (S(W)), vapor pressures (V(P)), sorption coefficients (K(OC)), octanol-water (K(OW)), octanol-air (K(OA)) and air-water (K(AW)) partition coefficients of 53 phthalates are studied by the quantitative structure-property relationship models by means of previously proposed Lu index. Reliable models are obtained to estimate Log ...
Aas Wenche - - 2009
A comprehensive field intercomparison at four different types of European sites (two rural, one urban and one industrial) comparing three different collectors (wet only, bulk and Bergerhoff samplers) was conducted in the framework of the European Committee for Standardization (CEN) to create an European standard for the deposition of the ...
Kasprzyk Idalia - - 2009
Forecasting the time when the atmospheric pollen season of allergenic plants begins is particularly important for doctors and their patients. The aim of this paper is to determine whether it is possible to forecast the start of the oak (Quercus) pollen season in Rzeszów, Poland. In the elaboration of the ...
Chrastansky Alena - - 2009
Lagrangian passive tracer transport simulations covering the 46-year period 1958-2003 were utilized to compare the exposures of different parts of the German North Sea coast to ship-related chronic oil pollution. Assuming the spatial distribution of oil releases to be proportional to estimated ship traffic density, detailed drift reconstructions allowed for ...
Zhang Xianming - - 2009
We adapted an indoor multimedia fugacity model to consider emissions and fate of polybrominated diphenyl ethers (PBDEs) and to understand the variability of indoor concentrations. The model was applied to an office in which an 80% decrease in PBDE air concentration was observed after an old computer was exchanged with ...
Becker Sara - - 2009
In 1974, Junge derived an empirical relationship between the variability of concentrations of volatile trace gases in air at remote locations and their atmospheric residence time. Here, the Junge relationship is adapted to incorporate the deposition and revolatilization of semivolatile chemicals and applied to interpret nearly a decade of data ...
Sidiropoulos Christos - - 2009
Solvent use and road transport are the two most significant sources of NMVOC emissions in urban environments. The allocation of emissions to solvent-related activities is of major importance since it is a major step towards providing spatially and temporally resolved accurate emission data in air quality models and assisting the ...
Beckx Carolien - - 2009
The potential advantages of using activity-based transport models for air quality purposes have been recognized for a long time but models that have been developed along these lines are still scarce. In this paper we demonstrate that an activity-based model provides useful information for predicting hourly ambient pollutant concentrations. For ...
Ainslie B - - 2009
We apply the entropy-based Bayesian optimizing approach of Le and Zidek to the spatial redesign of the extensive air pollution monitoring network operated by Metro Vancouver, in the Lower Fraser Valley, British Columbia. This method is chosen because of its statistical sophistication, relative to other possible approaches, and because of ...
Bohrerova Zuzana - - 2009
Pollen of forest trees can move on the scales of tens to hundreds of kilometers, but the question of its viability during this long distance dispersal (LDD) has yet to be answered. While empirical studies of pollen viability in forest tree species are rare, controlled and scalable data to outdoor ...
Xu Ying - - 2009
A two-room model is developed to estimate the emission rate of di-2-ethylhexyl phthalate (DEHP) from vinyl flooring and the evolving gas-phase and adsorbed surface concentrations in a realistic indoor environment. Because the DEHP emission rate measured in a test chamber may be quite different from the emission rate from the ...
Armitage James M - - 2009
The contamination of the Baltic Sea with polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) has resulted in restrictions on the marketing and consumption of Baltic Sea fish, making this a priority environmental issue in the European Union. To date there is no consensus on the relative importance of different sources of PCDD/Fs ...
Chang Ken-Hui - - 2009
The methyl tert-butyl ether (MTBE) concentration profiles near a MTBE manufacturing plant were monitored on two occasions. The US EPA's atmospheric dispersion model (industrial source complex short-term) was used to model the ambient MTBE levels with the input of local meteorological data as well as MTBE emissions from the plant. ...
Luz George - - 2009
A challenge for the proponents of soundscape analysis within the U.S. is how to integrate subjective observations with the quantitative requirements of the National Environmental Policy Act (NEPA), which, historically, emphasize physical measurements of all pollutants, including sound pollution. This paper describes a case study in which an attempt is ...
Chu Nanjun - - 2009
A simple statistical method is described for identifying the likely importance of local sources of PM2.5 in a region on days when the National Ambient Air Quality Standard is exceeded. The method requires only PM2.5 mass concentration and wind direction data, and makes use of the EPA database on PM2.5 ...
Pinder Robert W - - 2009
Because all models are a simplification of the phenomenon they aim to represent, it is often more useful to estimate the probability of an event rather than a single "best" model result. Previous air quality ensemble approaches have used computationally expensive simulations of separately developed modeling systems. We present an ...
Lipfert Frederick W - - 2009
For this paper, we considered relationships between mortality, vehicular traffic density, and ambient levels of 12 hazardous air pollutants, elemental carbon (EC), oxides of nitrogen (NOx), sulfur dioxide (SO2), and sulfate (SO4(2-)). These pollutant species were selected as markers for specific types of emission sources, including vehicular traffic, coal combustion, ...
Wood A M - - 2009
The aim of this study was to determine whether long-term air pollution exposure is associated with clinical phenotype in alpha(1)-antitrypsin deficiency. In total, 304 PiZZ subjects underwent full lung function testing and quantitative high-resolution computed tomography to identify the presence and severity of the disease. Mean annual air pollutant data ...
Su J G - - 2009
Land use regression (LUR) has emerged as an effective and economical means of estimating air pollution exposures for epidemiological studies. To date, no systematic method has been developed for optimizing the variable selection process. Traditionally, a limited number of buffer distances assumed having the highest correlations with measured pollutant concentrations ...
Ainslie B - - 2009
A means of determining air emission source regions adversely influencing the city of Prince George, British Columbia, Canada from potential burning of isolated piles of mountain pine beetle-killed lodge pole pine is presented. The analysis uses the CALPUFF atmospheric dispersion model to identify safe burning regions based on atmospheric stability ...
Bailey Robert E - - 2009
There are no longer any large scale uses of pentachlorobenzene (PeCB). Current emissions of PeCB to the environment are estimated to be about 121000kgy(-1), based on published information. The largest sources appear to be combustion of solid wastes, 32000kgy(-1), biomass burning, 45000kgy(-1) with degradation of an agricultural fungicide, quintozene, contributing ...
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