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Physicochemical Properties and Origin of PM1 Measured at a Rural Background Site
Pokorná, Petra ; Zíková, Naděžda ; Vodička, Petr ; Lhotka, Radek ; Mbengue, Saliou ; Holubová Šmejkalová, A. ; Riffault, V. ; Ondráček, Jakub ; Schwarz, Jaroslav ; Ždímal, Vladimír
This study assesses the variability of organic aerosol (OA) sources monitored at the rural background site Frýdlant. Non-refractory PM1 was evaluated in two seasons of\n2021. The positive matrix factorization with the multi-linear engine was used to determine the sources of OA at Frýdlant site, with four factors resolved both in winter and\nsummer.
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Planetary Boundari Layer Effect on Vertical Transport of Black Carbon Concentration under Different Meteorological Conditions
Julaha, Kajal ; Zíková, Naděžda ; Mbengue, Saliou ; Ždímal, Vladimír
In the present study, we analyzed the impact of equivalent black carbon (eBC) aerosols at two different heights (4 m and 230 m) on the PBL height under different \nmetrological conditions such as clear sky, foggy (visibility ≤ 1km), and hazy days (visibility ≤ 8km during the non-fog day), high relative humidity, temperature, and \nobservational data, also, diurnal and seasonal variability was evaluated.
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A Seven-Years Based Characterization of Aerosol Light Scattering Properties at Central European Rural Site: Variability and Source Apportionment
Suchánková, Lenka ; Mbengue, S. ; Zíková, Naděžda ; Ondráček, Jakub ; Holubová Šmejkalová, A. ; Prokeš, R. ; Holoubek, I. ; Ždímal, Vladimír
The aim of this study is to focus on the temporal variations of light-scattering properties of aerosols at a rural background site in Central Europe. The total light scattering (σsp) and backscattering (σbsp) coefficients and associated calculated optical properties such as the Ångström exponent (SAE), the backscattering ratio (b), and the asymmetry factor (g), are characterized considering different time scales (annual, seasonal, monthly, or diurnal) based on long-term measurement. The optical properties were compared with meteorological conditions (fog, cloudiness), the concentrations of gaseous pollutants such as NOx and SO2 were inspected as well as potential sources of atmospheric aerosols. In addition, radiative forcing, and the influence of other meteorological conditions (e.g., height of planetary boundary layer), chemical composition and particle size distribution at the National Atmospheric Observatory Košetice (NAOK) are being further investigated to better understand the direct effects of aerosols on the local climate.
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The Story of Teamwork and the Birth of the FFP* (Filter Backpack)
Fraenkl, M. ; Krbal, M. ; Houdek, J. ; Zmrhalová, Z. ; Prokeš, B. ; Hejda, P. ; Slang, S. ; Přikryl, J. ; Ondráček, Jakub ; Makeš, Otakar ; Kostyk, Juraj ; Nasadil, P. ; Malčík, P. ; Ždímal, Vladimír ; Vlček, M.
Soon after the outbreak of the coronavirus crisis in the Czech Republic and the first lockdown (2020), we enthusiastically decided to fight the coronavirus with scientific \nmeans. Originally materials engineers, we decided to develop an effective protective respiratory device, which was in short supply at the time. We soon found out, that every textile material (handkerchief 10%) has a certain ability to catch an aerosol particle carrying the corona virus, the slower the aerosol particle (d<300 nm) passes through the filter, the greater the chance it has of being caught, with the thickness of the filter, the amount of passed particles decreases exponentially and breathing resistance increases linearly. On this basis, we decided to experiment with a large-area filter placed on the user's back (it wouldn't fit anywhere else) and commercially available textile filter material.
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Chemical composition and sources of atmospheric aerosols at the Frýdlant background station
Lhotka, Radek ; Pokorná, Petra ; Vodička, Petr ; Zíková, Naděžda ; Ondráček, Jakub ; Arora, S. ; Poulain, L. ; Hermann, H. ; Schwarz, Jaroslav ; Ždímal, Vladimír
This study assesses the variability of organic aerosol (OA) sources monitored at the rural background site Frýdlant. Non-refractory PM1 was evaluated in two seasons of\n2021. The positive matrix factorization with the multi-linear engine was used to determine the sources of OA at Frýdlant site, with four factors resolved both in winter and\nsummer.
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The Impact of the IMO-2020 Shipping Regulation on the Atmospheric Deposition of Sulfur around the Western English Channel and the Use of the V/Ni ratio as a Shipping Marker.
Windell, L. ; Bell, T. ; White, C. ; Schwarz, Jaroslav ; Ussher, S.
Anthropogenic aerosols are shown to have a great impact on marine ecosystems and human health, with the shipping industry contributing as a significant source of these\nemissions, and annual growth on the rise. In the marine environment, shipping emissions often dominate atmospheric deposition of sulfur. With around 70% of shipping activity\nbeing carried out within 400 km of the coast, its contribution to atmospheric sulfur is of great interest. The International Maritime Organisation (IMO) introduced a regulation on\n01/01/2020 restricting global marine fuel sulfur content from 3.5% to 0.5% w/w. The vanadium/nickel (V/Ni) ratio has been widely used as a marker of shipping emissions, with the range of 2.5 to 4 indicating shipping activity. The regulation has called into question the viability of the earlier use of the V/Ni ratio.
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Total and Bioaccessible Fraction of Elements in Urban Aerosol
Mikuška, Pavel ; Cigánková, Hana ; Hegrová, J.
Atmospheric aerosols have significant impact on health and environment. Elements constitute an important particulate component which have received the attention to understand their environmental and health impacts. Elements enter the human body through inhalation of aerosols causing several health issue (asthma, cardiovascular and respiratory diseases, lung cancer).\nThe potential health effects of elements in PM depend on their toxicity, concentration, and bioaccessibility. It is assumed that the bioaccessible fraction of elements is more relevant for evaluating human health risks than the total concentration of elements. The aim of this study was to determine the total and bioaccessible concentration of elements in urban PM1 and PM2.5 aerosol during four seasons.
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Lidar Vertical Profile Analyzes at National Atmospheric Observatory Košetice during Volcano Eruption on La Palma Island.
Kostyk, Juraj ; Holubová Šmejkalová, A. ; Ištok, T. ; Ždímal, Vladimír
Volcanic eruptions are one of the most important sources of natural aerosol. Their negative impacts on air quality (the effects of volcanic exhaust) can be observed via long-range transport to locations far from the eruption. One of the most recent events of volcanic activity was a volcanic eruption on La Palma in the fall of 2021 (Cumbre Vieja Volcano, La Palma Island, Canary Islands, 28°36'54 ,N 17°52'07 ,W, 1,949 m a.s.l.). The impact of the volcanic eruption on air quality, which occurred 3600 km from the National Atmospheric Observatory Košetice, was studied using a combination of ground-based measurements and vertical profile analyzes. Since a new instrument (LIDAR) has extended the equipment of our station, vertical profile analyzes were performed.
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Čištění knihovních dokumentů pomocí dvvoufázového spreje
Mašková, Ludmila ; Smolík, Jiří ; Vávrová, P. ; Neoralová, J. ; Součková, M. ; Novotná, D. ; Jandová, Věra ; Ondráček, Jakub ; Ondráčková, Lucie ; Křížová, T. ; Kocová, K.
Bylo zkoumáno čištění částic z knihovních materiálů (papír, textil a kolagenové materiály) pomocí vysokorychlostního sněhového proudu CO2. Měření zahrnovala stanovení účinnosti čištění a vyhodnocení možných nežádoucích účinků. Metoda byla porovnána s čištěním dusíkovým proudem. Výsledky ukázaly, že sněhová tryska CO2 je schopen účinně odstraňovat částice z povrchů. U papíru a textilu nebyly pozorovány žádné nežádoucí účinky. Aplikace na kolagenové materiály však způsobila degradaci povrchu.
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