PRESENTATION AND STATISTICAL MODELING OF THE CONCENTRATION PROFILES FOR MAJOR AIR POLLUTANTS MONITORED WITHIN A ROMANIAN CITY

2019 ◽  
Author(s):  
Clementina Moldovan
Keyword(s):  
Statistical Modeling ◽  
Air Pollutants ◽  
Concentration Profiles

Characterizing the vertical concentration profiles of ship plumes with a microscale model - is it all Gaussian?

2020 ◽  
Author(s):  
Ronny Badeke ◽  
Volker Matthias ◽  
David Grawe ◽  
Heinke Schlünzen
Keyword(s):  
Air Pollutants ◽  
Least Square ◽  
Good Representation ◽  
Concentration Profiles ◽  
Microscale Model ◽  
Plume Temperature ◽  
Numerical Grid ◽  
Vertical Concentration Profile ◽  
Gaussian Polynomial ◽  
Minimization Approach

<p>Accurate modeling of ship emissions is a topic of increasing interest due to the ever-growing global fleet and its emission of air pollutants. With the increasing calculation power of modern computers, numerical grid models can nowadays be used to analyze effects of shipping emissions from global to local scales. However, modeling entire ports and larger domains still requires a good representation for the vertical concentration profile of single ship plumes. As the shape of the plume strongly varies depending on parameters like plume temperature, ship-induced turbulence and meteorological conditions, the plume dilution does not always appear to be represented by a simple Gaussian distribution. In this work, the microscale model MITRAS is used to calculate vertical concentration profiles of ship plumes under varying technical and meteorological scenarios. The resulting curves are fitted with different mathematical curves (e.g. Gaussian, Polynomial and Gamma distribution) by a least square minimization approach and the best representations for individual scenarios are discussed.</p>

British and Scandinavian lake sediment records of carbonaceous particles from fossil-fuel combustion

1990 ◽  
Vol 327 (1240) ◽  
pp. 319-323 ◽  
Keyword(s):  
Coal Combustion ◽  
Air Pollutants ◽  
Fossil Fuel ◽  
Fuel Combustion ◽  
Concentration Profiles ◽  
Fossil Fuel Combustion ◽  
Geographical Differences ◽  
Spheroidal Carbonaceous Particles ◽  
Carbonaceous Particles ◽  
Sediment Records

Spheroidal carbonaceous particles are emitted to the atmosphere during oil and coal combustion. The sedimentary record of these particles has been analysed for six Scottish, two Norwegian and one Swedish lake. Concentration profiles in the sediments parallel fuel-consumption trends. There are also large differences in carbonaceous particulate concentrations indicating geographical differences in loading of air pollutants from fossil-fuel combustion.

scholarly journals Concentration Profiles of Acidic and Basic Air Pollutants Around an Industrial Park of Taiwan

2004 ◽  
Vol 151 (1-4) ◽  
pp. 287-304 ◽  
Author(s):  
Chuen-Jinn Tsai ◽  
Shankar G. Aggarwal ◽  
Chung-Tso Chang ◽  
I-Fu Hung
Keyword(s):  
Air Pollutants ◽  
Industrial Park ◽  
Concentration Profiles

scholarly journals The use of tunnel concentration profile data to determine the ratio of NO<sub>2</sub>/NO<sub>x</sub> directly emitted from vehicles

2005 ◽  
Vol 5 (6) ◽  
pp. 12723-12740 ◽  
Author(s):  
X. Yao ◽  
N. T. Lau ◽  
C. K. Chan ◽  
M. Fang
Keyword(s):  
Air Quality ◽  
Urban Areas ◽  
Air Pollutants ◽  
Quality Data ◽  
Concentration Profiles ◽  
Profile Data ◽  
Annual Average ◽  
Air Quality Data ◽  
Monitoring Platform

Abstract. Recently, it is reported that primary vehicular NO2/NOx ratio to be 10–30% and primary vehicular NO2 has raised much interest and concern in the control of NO2 in urban areas. In this study, primary vehicular NO2/NOx ratio in Hong Kong was investigated based on intensive long tunnel (3.7–4 km in length) experiments where concentration profiles of air pollutants along the entire lengths of the tunnels were obtained. Long tunnels were selected because of the inherent low O3 concentrations in the partially enclosed environment. In addition the concentrations of pollutants from vehicles are high. Thus, the NO2 measured inside long tunnels would be more representative of the primary NO2 emitted by vehicles and contribution due to atmospheric transformation would be limited. This dataset was supported by a long-term on-road air quality dataset (June 2002–August 2003). Both datasets were obtained using the Mobile Real-time Air Monitoring Platform (MAP). The primary on-road vehicular NO2/NOx ratio was less than 2%, detected in the mid sections of tunnels investigated, where O3 concentration was at a minimum. In sections of the tunnels (entrance and exit) where O3 concentrations were relatively high, the NO2/NOx ratio could be as high as 19%. Long-term (annual average) on-road air quality data in open air yielded NO2/NOx ratios up to 28%. Thus, it is apparent that directly emitted NO2 from vehicles is not significant in atmospheric NO2 concentration. A simple model was used to segregate the contribution of background NO2 and transformed NO2 measured in vehicle plumes.

scholarly journals Statistical modeling of particle mater air pollutants in the city of Ruse, Bulgaria

2018 ◽  
Vol 145 ◽  
pp. 01010 ◽  
Author(s):  
Evelina Veleva ◽  
Ivanka Zheleva
Keyword(s):  
Air Pollution ◽  
Statistical Analysis ◽  
Statistical Modeling ◽  
Air Pollutants ◽  
Air Pollutant ◽  
Monitoring Station ◽  
Pm10 And Pm2.5 ◽  
Using Data ◽  
The City ◽  
Monitoring Stations

This paper is devoted to examine the PM10 and PM2.5 pollution in Ruse region, Bulgaria. It is a continuation of our previous work [1] where we presented a statistical analysis and modelling of the level of PM10 air pollution in Ruse using data from one of two monitoring stations (station 2) in the city. Now in this paper we present statistical analysis of the level of PM10 pollutant on the basis of data from the another monitoring station (station 1). The measurements cover the period since 2015 up to now. The results from analysis and modelling of PM2.5 air pollutant are also presented and commented in the paper.

Some Effects of Oxidant Air Pollutants (Ozone and Peroxyacetyl Nitrate) on the Ultrastructure of Leaf Tissues

1972 ◽  
Vol 30 ◽  
pp. 360-361
Author(s):  
William W. Thomson ◽  
Elizabeth S. Swanson
Keyword(s):  
Air Pollutants ◽  
Electron Microscopic Examination ◽  
Peroxyacetyl Nitrate ◽  
Electron Microscopic ◽  
Growth Physiology ◽  
Physiology And Biochemistry ◽  
Entire Plant ◽  
Leaf Tissues ◽  
Gaseous Hydrocarbons ◽  
The Individual

The oxidant air pollutants, ozone and peroxyacetyl nitrate, are produced in the atmosphere through the interaction of light with nitrogen oxides and gaseous hydrocarbons. These oxidants are phytotoxicants and are known to deleteriously affect plant growth, physiology, and biochemistry. In many instances they induce changes which lead to the death of cells, tissues, organs, and frequently the entire plant. The most obvious damage and biochemical changes are generally observed with leaves.Electron microscopic examination of leaves from bean (Phaseolus vulgaris L.) tobacco (Nicotiana tabacum L.) and cotton (Gossipyum hirsutum L.) fumigated for .5 to 2 hours with 0.3 -1 ppm of the individual oxidants revealed that changes in the ultrastructure of the cells occurred in a sequential fashion with time following the fumigation period. Although occasional cells showed severe damage immediately after fumigation, the most obvious change was an enhanced clarity of the cell membranes.

Freeze-dried dispersions for automated SEM analysis of individual submicron airborne particulates

1992 ◽  
Vol 50 (1) ◽  
pp. 408-409
Author(s):  
Karen A. Katrinak ◽  
David W. Brekke ◽  
John P. Hurley
Keyword(s):  
Air Pollutants ◽  
Size Range ◽  
Sem Analysis ◽  
Individual Particle ◽  
Chemical Data ◽  
Particle Analysis ◽  
Bulk Analysis ◽  
Airborne Particulates ◽  
Freeze Dried ◽  
Individual Particle Analysis

Individual-particle analysis is well established as an alternative to bulk analysis of airborne particulates. It yields size and chemical data on a particle-by-particle basis, information that is critical in predicting the behavior of air pollutants. Individual-particle analysis is especially important for particles with diameter < 1 μm, because particles in this size range have a disproportionately large effect on atmospheric visibility and health.

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