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NMR Aerosolomics: A Convenient Route to Organic Aerosol Analysis.
Horník, Štěpán ; Schwarz, Jaroslav ; Sýkora, Jan
Atmospheric aerosols are a small but very important part of the Earth’s atmosphere. The proportion of inorganic and organic compounds in aerosol particles seems to be equal on average. While the inorganic composition of aerosols is well explored, knowledge about the organic part is still very limited. It is well known that the major part of organic aerosol compounds is represented by polar, water-soluble organic compounds (WSOC). So far GC-MS is the most frequently used method for WSOC analysis. GC-MS is a very sensitive technique, furthermore, it exploits huge spectra libraries accumulated over decades. Therefore, its role in the determination of aerosol composition is indisputable. Primarily owing to GC-MS, about 150 organic compounds have been identified in aerosol particles. NMR spectroscopy for the purpose of aerosol chemistry was discovered only recently as it is rather insensitive method. Nevertheless, NMR has undergone rapid development and sensitivity gain of late. Moreover, it is fully quantitative method and no sample derivatization is needed. So far, the use of NMR spectroscopy has been limited to so called Functional group analysis. In this analysis the whole NMR spectrum is divided into parts and subsequently integrated according to functional groups.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22018110212472 - PDF
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Hydroscopic Behaviours of Ammonium Sulfate/Organic Mixtures Including Dicarboxylic Acid and Oligomer.
Bouzidi, Hichem ; Zuend, A. ; Ondráček, Jakub ; Schwarz, Jaroslav ; Ždímal, Vladimír
Here, the hygroscopic behavior of submicron particles composed of ammonium sulfate (AS), dicarboxylic acids (including oxalic acid (OA), malonic acid (MA)), and oligomer Poly(ethylene glycol) (PEG-300 (-CH2OCH2-)n) is investigated with a Hygroscopicity Tandem Differential Mobility Analyzer (HTDMA), under relative humidity (RH) below 100%. The aerosol systems were varied in their complexity and ranged from single-component to more complex systems (2, 3 and 4 components). The experimental data are compared with predictions from Zdanovskii-Stokes-Robinson (ZSR) mixing rule (Stokes and Robinson, 1966) and the thermodynamic model Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients (AIOMFAC) (Zuend et al., 2011).
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22018110212480 - PDF
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ACTRIS - Contribution of the Czech Republic: National and Central Facilities.
Ondráček, Jakub ; Holubová, Adéla ; Komínková, Kateřina ; Vítková, Gabriela ; Schwarz, Jaroslav ; Klánová, J. ; Holoubek, Ivan ; Váňa, M. ; Ždímal, Vladimír
ACTRIS (Aerosols, Clouds and Trace gases Research Infrastructure) is an initiative gathering partners all over Europe concentrating on high-quality observations of different atmospheric processes. ACTRIS aims to provide high quality open access data of aerosols, clouds and trace gases and to create a platform for researchers to combine their efforts in resolving the most important environmental challenges (such as air quality, health, climate change, etc.). It is a logical continuation of 15 years of development funded by both Member States and the European Commission through the Research Infrastructure programme (including EARLINET, EUSAAR, CREATE and Cloudnet). ACTRIS has become an important pan-European research infrastructure in 2016 by being accepted into ESFRI (The European Strategy Forum on Research Infrastructure) Roadmap. Currently the ACTRIS is in the phase of becoming pan-European research infrastructure with its own legal entity and operational structure, being supported by two EU projects (ACTRIS-2 and ACTRIS PPP – Preparatory Phase Project).
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Plný tet: SKMBT_C22018110212490 - PDF
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Characterization of Equivalent Black carbon (EBC) at a Regional Background Site in Central Europe: Variability and Source Identification.
Mbengue, S. ; Serfozo, N. ; Holubová Šmejkalová, Adéla ; Holoubek, I.
Black carbon (BC) is recognized to play an important role on adverse public health and in the Earth’s climate system (Bond et al., 2013). It is the most efficient light-absorbing aerosol species in the visible spectrum emitted as primary pollutant from a variety of combustion related sources. Although measurements of Equivalent Black Carbon (EBC) with multiple wavelength aethalometer have been used to provide insights regarding the influence of fossil fuel (traffic emissions) and wood smoke in ambient air (Sandradewi et al., 2008, Vaishya et al. 2017), scarce studies have been reported in Eastern Central Europe using real-time EBC measurements.\nThis study focuses on the seasonal, diurnal and weekly trends of EBC at a regional background site in Central Europe during a 5-year measurement. Our aim is to identify the potential sources of EBC, especially the influence from fossil fuel and biomass burning.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22018110212461 - PDF
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Characterization of equivalent black carbon (ebc) at a regional backgound site in Central Europe: Variability and source identification
Mbengue, Saliou ; Šerfözö, Norbert ; Holubová Šmejkalová, Adéla ; Holoubek, Ivan
Black carbon (BC) is recognized to play an important role on adverse public health and in the Earth’s climate system (Bond et al., 2013). It is the most efficient light-absorbing aerosol species in the visible spectrum emitted as primary pollutant from a variety of combustion related sources. Although measurements of Equivalent Black Carbon (EBC) with multiple wavelength aethalometer have been used to provide insights regarding the influence of fossil fuel (traffic emissions) and wood smoke in ambient air (Sandradewi et al., 2008, Vaishya et al 2017), scarce studies have been reported in Eastern Central Europe using real-time EBC measurements.\nThis study focuses on the seasonal, diurnal and weekly trends of EBC at a regional background site in Central Europe during a 5-year measurement. Our aim is to identify the potential sources of EBC, especially the influence from fossil fuel and biomass burning.
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Use of the ceilometer data to explainig changes in pollutants concetration gradient in the air during the day
Komínková, Kateřina ; Holoubek, Ivan
For the interpretation of air pollutants concentrations, the one of the key parameter is the atmospheric boundary layer (ABL) evolution during a day and night. The ABL is a broad concept that includes different states of airflow dynamics in the part of troposphere closest to the Earth's surface (0-2 km above the surface), which has an effect in this area. A lot of air flow changes occur in the ABL during the day. For the measurement of substances concentrations in the air the development of mixing layer (ML) in the light part of the day is very important. A lot of ground remote sensing methods was developed for determination of ABL height during the day, one of them which can be very simply operated is to use data from ceilometer. However, the obtained outputs cannot be directly interpreted. In addition, in the case of the terrain measurements a lot of cases when ABL height values cannot be determined because the ceilometer measurement is disturbed can occur.\n\n
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Comparison of Atmospheric Aerosol Volatility at a Rural Site in Central Europe.
Kubelová, Lucie ; Vodička, Petr ; Makeš, Otakar ; Zíková, Naděžda ; Ondráček, Jakub ; Schwarz, Jaroslav ; Ždímal, Vladimír
Volatility is an important characteristic of atmospheric aerosols as it affects their origin, lifetime and removal. Accurate description of aerosol volatilities is important for models calculating condensation of semi-volatile species and it also enables better identification of aerosol sources (Wu et al., 2009). However, our understanding of volatilities of organic atmospheric aerosols and the related processes is still rather poor (Han et al., 2016.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22017103113060 - PDF
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Seasonal, weekly and diurnal variability of elemental and organic carbon at a rural background site in Central Europe, a four years of measurement
Mbengue, Saliou ; Fusek, M. ; Schwarz, Jaroslav ; Vodička, Petr ; Holubová, Adéla ; Holoubek, Ivan
Atmospheric organic (OC) and elemental (EC) carbon play an important role in\natmospheric chemistry, climate change and public health. There have been relatively\nfew studies dealing with EC and OC in rural background sites which are less influenced\nby urban and industrial emissions. Nevertheless, measurements at background areas are\nimportant for understanding the transport and transformation characteristics of\nanthropogenic air pollutants, and their effects on various aspects of regional and global\nenvironment changes. This work is one of the rare studies using a semi-continuous\nmeasurement technique to focus on long-term (4 years) measurements of EC and OC at\nregional background site in Europe. It focuses on the factors or phenomena influencing\nboth diurnal and weekly variability of EC and OC concentrations during various seasons\nat rural background area.
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