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Size Dependence of Incorporation of Gas Molecules into Aerosol Nanoparticles
Levdansky, V.V. ; Smolík, Jiří ; Ždímal, Vladimír ; Moravec, Pavel
The influence of size effects on the physicochemical transformations and transfer phenomena in the heterogeneous systems with nanoobjects attracts increasing attention of researchers. These problems are of interest for nanotechnology and atmospheric physics. Size effects can influence the cohesive energy as well as the activation energies of vacancy formation and diffusion of atoms in the nanoscale particles (Vanithakumari and Nanda, 2008). Phase transitions in aerosol systems with nanoscale particles (clusters) also depend on the nanoparticle size (Levdansky et al., 2010). Hear we discuss the size dependence of the mass accommodation coefficient in the aerosol system with nanoparticles.
Plný tet: SKMBT_C22013091912290 - PDF Plný text: content.csg - PDF
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Comparison of Particle Number Size Distributions in Three Central European Capital Cities
Zíková, Naděžda ; Borsós, T. ; Řimnáčová, Daniela ; Smolík, Jiří ; Wagner, Zdeněk ; Weidinger, T. ; Burkart, J. ; Steiner, G. ; Reischl, G. ; Hitzenberger, R. ; Schwarz, Jaroslav ; Salma, I. ; Ždímal, Vladimír
Health aspects of ultrafine aerosol particles in urban environment have been studied extensively in recent years (Salma et al., 2011; Putaud et al., 2010; Qian et al., 2007 etc.). Three main sources of the ultrafine particles have been defined – traffic, biomass burning, and atmospheric nucleation. However, the diurnal changes in intensities of individual sources are of considerable extent, similarly to the scale of variations in particle number concentrations due to meteorological phenomena.
Plný tet: SKMBT_C22013091814450 - PDF Plný text: content.csg - PDF
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Ultrafine Particle Concentrations: Importance of Local Sources and New Particle Formation in Two Central European Cities
Wonaschuetz, A. ; Wagner, R. ; Aschauer, I. ; Haindl, R. ; Ludwig, W. ; Zecha, G. ; Ondráček, Jakub ; Vodička, Petr ; Zíková, Naděžda ; Ždímal, Vladimír ; Schwarz, Jaroslav ; Hitzenberger, R.
In this study, the importance of local primary sources and new particle formation as sources of fine and ultrafine particles is investigated for winter and summer in two central European cities. Particular attention is given to the impact of local meteorological characteristics: air mass origins play a large role in the characteristics of the background aerosol and the concentrations of trace gases associated with new particle formation and growth, and precipitation and thus the condensational sink.
Plný tet: SKMBT_C22013091713550 - PDF Plný text: content.csg - PDF
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A 19m Deep Well – a Downward Thermal Diffusion Cloud Chamber?
Holub, R.F. ; Hopke, P.K. ; Hovorka, J. ; Otahal, P. ; Ždímal, Vladimír
An unusual phenomenon, first observed on a clear summer day after several rainy days, were droplets constantly hitting the water surface in a 19 m deep and 2.4 m diameter water well. This droplet formation was occurring during the night as well. Since the droplet formation was near continuous, we called it “the eternal rain”. The water well is about 230 years old and located in the Benedictine monastery in Broumov, Czech Republic.
Plný tet: SKMBT_C22013091713150 - PDF Plný text: content.csg - PDF
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Comparability of Methods to Measure Black and Elemental Carbon in Two European Urban Areas - Site and Seasonal Similarities and Differences
Hitzenberger, R. ; Schwarz, Jaroslav ; Aschauer, I. ; Haindl, R. ; Ludwig, W. ; Wagner, R. ; Wonaschuetz, A. ; Zecha, G. ; Ševčíková, Irena ; Vodička, Petr ; Zíková, Naděžda ; Ždímal, Vladimír
The goal of the current study is to investigate whether similar conversion factors are applicable at the sites and whether the conversion factors obtained earlier (i.e. ca. 10 years ago) for Vienna are still valid or whether changing source conditions have resulted in shifts of the carbonaceous fractions of the aerosol that would require a new set of conversion factors.
Plný tet: SKMBT_C22013091712210 - PDF Plný text: content.csg - PDF
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Number Concentration and Modal Structure of Indoor/Outdoor Fine Particles in Four European Cities
Lazaridis, M. ; Eleftheriadis, K. ; Ždímal, Vladimír ; Schwarz, Jaroslav ; Wagner, Zdeněk ; Ondráček, Jakub ; Drossinos, Y. ; Glytsos, T. ; Vratolis, S. ; Torseth, K. ; Smolík, Jiří
Indoor/outdoor measurements campaigns were performed in naturally ventilated houses and offices in four European cities to investigate the relationship between indoor and outdoor particle number concentrations and aerosol modal structures. The measurements sites were located in Oslo (Norway), Prague (Czech Republic), Milan (Italy) and Athens (Greece). A number of ordinary indoor activities (cooking, smoking, candle burning, etc.) were performed during the measurements to quantify the contribution of particles emitted from indoor sources and the contribution of outdoor particles to the change of the indoor aerosol size spectra.
Plný tet: SKMBT_C22013091712000 - PDF Plný text: content.csg - PDF
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Air Mass Back Trajectories and Dry Atmospheric Aerosol Mass Size Distributions in Prague
Schwarz, Jaroslav ; Štefancová, Lucia ; Maenhaut, W. ; Smolík, Jiří ; Ždímal, Vladimír
Ambient aerosol size distribution is an important factor influencing aerosol behavior and properties including particle deposition in lungs and aerosol influence on clouds. Both influences are also driven by aerosol hygroscopicity. Cascade impactors used for size resolved determination of chemical composition suffer from changes of ambient RH during sampling. Due to this factor the same particle might be deposited at different impactor stage when it is sampled at noon at 40% RH or in the early morning at 99% RH. Therefore, we used a diffusional aerosol dryer and a 7-stage modified Berner low pressure impactor with a back-up filter during the heating campaigns in 2008. The samples were analyzed for water-soluble ions (Cl-, SO42-, NO3-, Na+, NH4+, K+, Mg2+, Ca2+) and water-soluble organic carbon as a main species that influence aerosol hygroscopicity. Due to the drying, the aerosol size distributions were not influenced by the daily variability of ambient relative humidity.
Plný tet: SKMBT_C22013091814570 - PDF Plný text: content.csg - PDF
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