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Variability of Aerosols and Chemical Composition of PM10, PM2.5 and PM1 on the Platform of the Prague Underground Metro
Cusack, Michael ; Talbot, Nicholas ; Ondráček, Jakub ; Minguillon, M.-C. ; Schwarz, Jaroslav ; Otáhal, P. ; Klouda, K. ; Ždímal, Vladimír
The aim of this study is to describe aerosol concentrations and variability, and chemically characterise PM sampled during a 24 hour period on a platform of the Prague underground metro system. To this end, PM and particle number concentration and size distribution are described, and the chemical composition of PM in various size fractions is discussed, both for periods when the metro was out of operation and operational.
Plný tet: SKMBT_C22014102013562 -  PDF
Plný text: content.csg - PDF
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Characterization of Particulate Matter in Different Archives
Mašková, Ludmila ; Smolík, Jiří ; Vodička, Petr
Indoor air pollution in cultural heritage buildings such as museums, libraries and archives can be harmful for materials stored there. Adverse effects of most of gaseous pollutants are well described (Thomson, 1965), but less is known about airborne particles. Particles cover a wide range of sizes and have a variable composition. These characteristics determine their transport to the surfaces and also possible negative effects (Nazaroff and Cass, 1989).
Plný tet: SKMBT_C22014102013561 - PDF
Plný text: content.csg - PDF
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A Comparison of Titania Nanoparticles Production in Two Different Reactors by MOCVD Method
Moravec, Pavel ; Smolík, Jiří ; Schwarz, Jaroslav ; Vodička, Petr ; Levdansky, V.V. ; Koštejn, Martin
Nanoparticles (NP's) have attracted considerable attention, because they show a quantum size effect, for which the physical and chemical properties are strongly dependent on particle size. This change of properties can also affect the toxicity and therefore NP's cannot be treated the same way as bulk material. In spite of that, inhalation studies of NP's are still rather rare. Recently, an exposure system for inhalation experiments was constructed in the Institute of Analytical Chemistry AS CR and the first experience with this system were reported by Večeřa et al., 2012. For these studies, a method of continual long-term generation of NP's in the gas phase is necessary. Methods for long-term generation of MnOx and Pb/PbOx NP's have recently been reported. The next task was to test the method for long-term generation of TiO2 NP's suitable for subsequent inhalation experiments.
Plný tet: SKMBT_C22014102013554 - PDF
Plný text: content.csg - PDF
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Impact of Size Effects on Formation of Nanoparticles from Supersaturated Vapor
Levdansky, V.V. ; Smolík, Jiří ; Ždímal, Vladimír ; Moravec, Pavel
The mechanism of nanoparticle formation in condensation of a supersaturated vapor is of interest for different kinds of atmospheric phenomena and processes of nanotechnology (e.g. manufacture of nanoparticles). Homogeneous nucleation is the initial stage of nanoparticle formation. The critical cluster size is one from the main parameters in the classical nucleation theory. The value of the critical cluster size is usually found from the Kelvin equation which does not depend on the condensation coefficient. In the general case the size dependence of the condensation coefficient can influence the critical cluster size (Levdansky, 2002). The size dependence of the cohesive energy in the nanoparticle can also affect the size of the critical cluster. Below we consider the joint influence of above-mentioned size effects on the critical cluster size, the rate of nucleation and the growth rate of arising nanoparticles.
Plný tet: SKMBT_C22014102013552 - PDF
Plný text: content.csg - PDF
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Search for Links between Organic Aerosols Measured by Aerosol Mass Spectrometer and EC/OC Analyzer
Vodička, Petr ; Kubelová, Lucie ; Makeš, Otakar ; Schwarz, Jaroslav
Carbonaceous aerosols form a major part of particulate matter suspended in the atmosphere. The organic part of aerosol represents a diverse group of substances that can be analyzed in different ways. In this work, the possible linkages between organic fractions measured by Compact Time-of-Flight Aerosol Mass Spectrometer (AMS; from Aerodyne) and a semi-online EC/OC analyzer (from Sunset Laboratories) were search. Each of these instruments provides a different kind of information. Organic fractions from EC/OC analyzer provide knowledges about a diferent volatility of organic carbon (OC) while AMS provide informations about a chemical composition of characteristic mass fragments. Thus, the main objective of this work was to determine whether the organic fractions from EC/OC analyzer can indirectly provide also information on the chemical composition or somehow more characterize type of aerosol.
Plný tet: SKMBT_C22014102013551 - PDF
Plný text: content.csg - PDF
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Comparison of Source Apportionment Results from Summer and Winter Measuring Campaign at a Prague-Suchdol Site
Makeš, Otakar ; Vodička, Petr ; Schwarz, Jaroslav
Organic aerosol (OA) is the most abundant but still poorly characterized component of airborne particulate matter. This situation is even more complicated in large cities where many anthropogenic sources of primary organic aerosol (POA) are situated. In recent years, aerosol mass spectrometry has been increasingly applied to obtain highly time-resolved chemical composition of ambient aerosol. This is considerably important for clarification of organic aerosol life cycles and sources. Two measuring campaigns, which lasted about six weeks in summer 2012 and in winter 2013, were performed at suburban site Prague – Suchdol. Aerosol data were measured by Aerodyne compact time-of-flight aerosol mass spectrometer (AMS) which is able to characterize the size resolved chemical composition of non-refractory submicron (PM1) fraction.
Plný tet: SKMBT_C22014102013550 - PDF
Plný text: content.csg - PDF
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