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Trends of PM2.5 and Chemical Composition in at a Regional Backround Site in the Western Mediteranean over the Past Nine Years
Cusack, Michael ; Alastuey, A. ; Perez, N. ; Pey, J. ; Querol, X.
The findings in this article provide good evidence that the implementation of Pollution abatement strategies in Europr is having a direct effect on the level of PM2.5 and its various components. It is also hypothesised that the current economic climate, in reccesion since mid 2008 in Spain and many counties in Europe, is also affecting atmospheric pollutants through a reduction in activities associated with a healthy economy. A reduction in PM2.5 concentrations has been observed in Spain and across Europe, in most cases, this reduction has been gradual and consistent over time, implying the success of cleaner anthropogenic activities. Additional to this progressive trend, in some cases and especially for RB stations in the IP and Ispra in nothern Italy, a marked decrease has been recorded since 2008, coinciding with the begidding of the economic crisis. Finally, large scale meteorology has been shown to be an important influental factor on ambient aerosol concentrations across the Iberian Peninsula, with the North Atlantic Oscillation controlling the frequency of Sahara dust instrusions across the Iberian Peninsula in winter. Specially at MSY, organic matter and secondary inorganic aerosol accounted for the majority of the reduction observed.
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Plný tet: SKMBT_C22013112516390 - PDF
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Identifying of Organic Aerosol Sources by Using of Advanced Factor Analysis
Makeš, Otakar ; Vodička, Petr ; Schwarz, Jaroslav ; Canonaco, F. ; Prevot, A.
Real-time measurement of submicron aerosol was performed at Prague – Suchdol site (Czech Republic) during six weeks in June and July 2012. Organic aerosol data obtained from measurement by C-ToF AMS were deconvoluted using the Multilinear Engine (ME-2) algorithm (Paatero, 1999) and analyzed with the newly developed GUI provided by Paul Scherrer Institute (Canonaco et al. in prep.). During the analysis, we obtained four factor solution which explains more than 95% of the variance. These four factors, related to four aerosol sources, were fixed by the ME-2 model: Hydrocarbon-like organic aerosol (HOA) factor related to the road traffic, biomass burning organic aerosol (BBOA) factor, and two kinds of oxygenated organic aerosol factors (LV-OOA and SV-OOA). LV-OOA factor is the most frequently interpreted as an aged aerosol with low volatility. On the contrary, diurnal patterns of SV-OOA factor exhibit maxima at night and high anti-correlation with temperature. Therefore it can be assumed that SV-OOA factor represents a volatile fraction of OOA.
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Plný tet: SKMBT_C22013101814580 - PDF
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Modelling of Sulfuric Acid Nanoparticles Growth
Škrabalová, Lenka ; Brus, D. ; Antilla, T. ; Ždímal, Vladimír ; Lihavainen, H.
Aerosol particles influence global radiative balance and climate directly through scattering and absorbing solar radiation and indirectly by acting as condensation cloud nuclei. The atmospheric nucleation is often followed by a rapid growth of freshly formed particles. The initial growth of aerosol is the crucial process determining the fraction of nucleated particles growing into cloud condensation nuclei sizes (~ 50 nm and larger). The subject of this study is modelling of growth behaviour of sulfuric acid nanoparticles produced by nucleation of water and sulfuric acid under wet and dry conditions.
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Plný tet: SKMBT_C22013101814581 - PDF
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Fog and Cloud Processingof SMPS Spectra
Zíková, Naděžda ; Ždímal, Vladimír
Atmospheric aerosols have been studied extensively due to the confirmed influence of aerosols on global climate, aerosol – clouds interactions, atmospheric visibility, human health etc. (Kerminen et al., 2005; IPCC, 2007; Wichmann et al., 2000). However, the uncertainties connected to the effects of aerosols on phenomena in the atmosphere are considerable – there are various sources of aerosol particles, having different chemical compositions and particle size distributions (PSD). Moreover, the atmospheric aerosol is exposed to both dry and wet deposition, which further inflences the PSD. In this work, we have focused on cloud and fog processing of aerosol PSD.
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Plný tet: SKMBT_C22013101814583 - PDF
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Influence of Size Effect on Evaporation of Aerosol Nanoparticles
Levdansky, V.V. ; Smolík, Jiří ; Ždímal, Vladimír
Evaporation of nanoscale particles plays a significant role in many branches of nanotechnology and also in the atmospheric physics and chemistry. The classical approach to the description of evaporation of small (nanoscale) aerosol particles is usually based on the Kelvin equation. The mentioned equation was used in (Nanda et al., 2003) to interpret the results of experiments related to evaporation of free Ag nanoparticles. The authors of the above-mentioned paper assume that the surface tension of free Ag nanoparticles can be significant greater than the mentioned value for bulk matter. It is worth noting that this assumption is in contradiction with the Tolman theory (Tolman, 1949). Below we consider the influence of the size dependence of the cohesive energy in the nanoparticle on its evaporation.
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Plný tet: SKMBT_C22013101814594 - PDF
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Synthesis of Lead and Lead Oxide Nanoparticles for Inhalation Experiments
Moravec, Pavel ; Smolík, Jiří ; Ondráček, Jakub ; Vodička, Petr ; Fajgar, Radek
From the three tested methods of NP's generation the evaporation/condensation of metallic Pb seems to be the most suitable for long lasting inhalation experiments due to its simplicity, unambiguous mechanism of NP′s formation and well defined composition. Nevertheless, NP′s can change their composition, at least on the surface layer, during the time-lag between their formation and inhalation. Thermal decomposition of PbTHD2 can produce sufficiently high concentration of NP′s but there is some uncertainty about their composition due to presence of OC in NP′s. Oxidation of PbTHD2 produces carbon free NP′s, but the number concentration of NP′s is somewhat low.
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Plný tet: SKMBT_C22013101814595 - PDF
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Mass Size Distribution of Atmospheric Aerosols and Water Soluble Ions atMlada Boleslav in Winter
Schwarz, Jaroslav ; Zíková, Naděžda ; Vodička, Petr ; Hovorka, J. ; Moravec, Pavel ; Ždímal, Vladimír
The importance of the knowledge of aerosol mass size distribution for understanding aerosol behavior is well known for at least few decades. The water soluble ions represent a driving factor controlling hygroscopicity of aerosol particles that determines how the ambient relative humidity influences aerosol particle size. Therefore, hygroscopicity is a substantial parameter in phenomena like particle deposition in the human respiratory tract, particle – cloud interactions, aerosol optical effects etc. For these reasons, the mass size distribution of atmospheric aerosols and water soluble ions was studied at a Czech medium-size-town Mladá Boleslav in winter.
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Plný tet: SKMBT_C22013101815000 - PDF
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