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Dissolved and gaseous nitrogen losses in forests controlled by soil nutrient stoichiometry
Oulehle, Filip; Chuman, T.; Hruška, Jakub; Krám, Pavel; Navrátil, Tomáš; Tesař, Miroslav; Ač, Alexander; Urban, Otmar
2023 - anglický
This study investigates the consequences of chronic nitrogen deposition in forests, including its effects on soil and surface water quality, and greenhouse gas emissions. To predict these effects, the authors explore the controls over dissolved and gaseous nitrogen fluxes in temperate forests. Their findings indicate that stream leaching losses of dissolved nitrogen correspond with the nutrient stoichiometry\nof the forest floor, with stream N losses increasing as ecosystems progress towards phosphorus limitation. Soil nitrogen storage increases with oxalate extractable iron and aluminium content. The authors estimate soil gaseous losses based on 15 N stocks, which averaged 2.5±2.2 kg N ha-1 year-1 , comprising 20±14% of total nitrogen deposition. They also extrapolate the current gaseous nitrogen loss flux from forests globally to be 8.9 Tg N year-1 , which represents 39% of current nitrogen deposition to forests worldwide.
Klíčová slova:
nitrogen; catchment; isotope; mass balance; denitrification; carbon; sequestration
Plné texty jsou dostupné v digitálním repozitáři Akademie Věd.
Dissolved and gaseous nitrogen losses in forests controlled by soil nutrient stoichiometry
This study investigates the consequences of chronic nitrogen deposition in forests, including its effects on soil and surface water quality, and greenhouse gas emissions. To predict these effects, the ...
Hazardous components: A case study in textile waste management
Shtukaturova, Anastasia
2023 - anglický
Textile waste, a problem that has been somewhat overlooked for many years, is now coming to the fore.1 The textile value chain is long\nand complex, with over 8000 chemicals used in different manufacturing processes.2 A wide variety of chemicals are used in the manufacture of textile products for the improvement of essential properties and performance of textiles. Chemicals used in textiles significantly improve their quality and appearance. However, the harmful effects of these chemicals can occur at various stages of textile production and processing, such as dyeing, printing and finishing, as well as during use by consumers and at the end-of-life stage.3 There is a lack of safety information on the presence and use of all of these chemicals in consumer products.
Klíčová slova:
textile waste; waste management; chemicals
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Hazardous components: A case study in textile waste management
Textile waste, a problem that has been somewhat overlooked for many years, is now coming to the fore.1 The textile value chain is long\nand complex, with over 8000 chemicals used in different ...
Properties and use of high-temperature biochar
Sedmihradská, Anežka
2023 - anglický
Despite being a hot topic in environmental research, biochar and its properties have been mainly investigated from the perspectives of feedstock type and pyrolysis temperature. Few studies have explored the effect of particle size on biochar properties.Even when the effect of particle size on crop efficiency is recognized, there is a lack of corresponding data and analysis.2–7 Therefore, we thoroughly analyzed (proximate and ultimate analysis, SEM, XRD, Raman spectroscopy) four particle size fractions (< 0.5, 0.5–2, 2–5, > 5 mm) of high-temperature biochar from a gasification power plant, the sizes reflecting those of biochar actually used in agriculture. The < 0.5 mm fraction was significantly different in terms of carbon structure, and carbon and ash content. Consequently, pH, electric conductivity and heavy metal content also differed greatly. The corresponding results for the other particle fractions were broadly similar to each other. Interestingly, for all fractions, the porosity and H/C ratio were independent of particle size, meaning that, regardless of size, the investigated biochar fractions are equally stable in soil. The 0.5–2 mm fraction was then selected to be used in different industrial or agricultural processes such as the anaerobic digestion of wastewater or livestock feeding. The effect of biochar on these processes is currently under investigation, providing only initial data so far.
Klíčová slova:
biochar; particle size on biochar; high-temperature biochar
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Properties and use of high-temperature biochar
Despite being a hot topic in environmental research, biochar and its properties have been mainly investigated from the perspectives of feedstock type and pyrolysis temperature. Few studies have ...
Vertical gradients of atmospheric aerosols chemical composition
Kovářík, Jiří
2023 - anglický
The aim of this work is to obtain data on the chemical composition of aerosols at two heights (4–5 metres above ground and at 230 metres on the atmospheric tower’s measurement platform). The following and sampling techniques will be used: Aerosol Mass\nSpectrometry) – in combination with PMF (Positive Matrix Factorisation), Aerosol Chemical Speciation Monitor and Particle Into Liquid Sampler coupled with Ion Chromatography.
Klíčová slova:
aerosols; analytical methods; chemical composition
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Vertical gradients of atmospheric aerosols chemical composition
The aim of this work is to obtain data on the chemical composition of aerosols at two heights (4–5 metres above ground and at 230 metres on the atmospheric tower’s measurement platform). The following ...
Liquid mixing time and gas holdup in a bubble column bioreactor
Terentyak, Mark
2023 - anglický
The aim of the research is the experimental study of homogenisation and saeration in a bubble column in dependence on operational conditions and aspect ratio.
Klíčová slova:
bubble column bioreactor; gas holdup; experiments
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Liquid mixing time and gas holdup in a bubble column bioreactor
The aim of the research is the experimental study of homogenisation and saeration in a bubble column in dependence on operational conditions and aspect ratio.
SUBMIKRONOVÝ AEROSOL NA DVOU MĚSTSKÝCH STANICÍCH V PRAZE
Pokorná, Petra; Zíková, Naděžda; Vodička, Petr; Lhotka, Radek; Ondráček, Jakub; Schwarz, Jaroslav; Ždímal, Vladimír; Hopke, P.
2023 - český
Cílem této práce bylo stanovit dynamiku submikronového aerosolu, jeho chemické složení a původ na dvou lokalitách v Praze na základě distribuce velikosti částic (PNSD) a chemického složení 2/12/24h vzorků atmosférického aerosolu (PM1) odebíraných paralelně po dobu půl roku/ve dvou ročních obdobích na dvou městských lokalitách (příměstské - Suchdol a dopravní - Vršovice). Byla provedena chemická analýza PM1 na uhlík (elementární, ekvivalentní černý - eBC a organický) termooptickou metodou a na anorganické ionty rozpustné ve vodě metodou IC. U většiny měsíců byl zjištěn jak početní, tak hmotnostní medián koncentrace založené na údajích SMPS lišily. Vyšší koncentrace eBC byly naměřeny ve Vršovicích, avšak koncentrace eBC vykazovaly dobrou korelaci (r=0,80, yintercept=0) na obou stanicích. Vyšší průměrné hodnoty PM1 na dopravní lokalitě v létě a na příměstské lokalitě v zimě a sezónní rozdíly v iontovém složení PM1 odrážely sezónnost místních zdrojů. Přesto nebyly mezi lokalitami zjištěny statisticky významné rozdíly v koncentraci PM1 a iontovém složení. The aim of this work was to determine the submicron aerosol dynamics, chemical compositions, and origins at two sites in Prague based on the particle number size distribution (PNSD) and chemical composition of 2/12/24h atmospheric aerosol samples (PM1) collected in parallel for half-year/within two seasons at two urban sites (suburban – Suchdol and traffic – Vršovice). Chemical analysis of PM1 for carbon (elemental, equivalent black – eBC and organic) by thermo-optical method and for water-soluble inorganic ions by IC was performed. For most months, both number and mass median \nconcentrations based on the SMPS data differed. Higher eBC concentrations were measured in Vršovice however eBC concentrations showed good correlation (r=0.80, yintercept=0) at the two stations. Higher average PM1 at the traffic site in summer and at the suburban site in winter, and seasonal differences in ionic PM1 composition reflected the seasonality of the local sources. Nevertheless, there were no statistically significant differences in PM1 concentration and ionic composition between the sites.
Klíčová slova:
particle number size distribution; chemical composition; identification sources
Plné texty jsou dostupné v digitálním repozitáři NUŠL
SUBMIKRONOVÝ AEROSOL NA DVOU MĚSTSKÝCH STANICÍCH V PRAZE
Cílem této práce bylo stanovit dynamiku submikronového aerosolu, jeho chemické složení a původ na dvou lokalitách v Praze na základě distribuce velikosti částic (PNSD) a chemického složení 2/12/24h ...
TRACERY ANTROPOGENNÍCH A BIOGENNÍCH ZDROJŮ ORGANICKÉHO AEROSOLU V PM1 FRAKCI NA POZAĎOVÉ STANICI KOŠETICE
Vodička, Petr; Kawamura, K.; Deshmukh, D.K.; Pokorná, Petra; Schwarz, Jaroslav; Ždímal, Vladimír
2023 - český
V této studii jsme podrobně zkoumali sezónní změny koncentrace cukrů, dikarboxylových kyselin a jejich oxidačních prekurzorů v jemném aerosolu na venkovském středoevropském pozadí. Cílem studie bylo identifikovat typické stopové prvky pro různé zdroje organického aerosolu a určit jejich podíl na organickém PM1. zjistili jsme zřetelný rozdíl mezi zimním a letním složením aerosolu PM1 na molekulární úrovni. Následně jsme identifikovali dva biogenní faktory (dominantní v létě), dva antropogenní faktory (hlavní příspěvek v zimě) a jeden faktor pozadí.\nPodrobnější informace bylo možné nalézt v publikaci Vodička et. al (2023). In this study, we have examined in detail the seasonal changes in the concentration of sugars, dicarboxylic acids and their oxidation precursors in fine aerosol at a rural Central European background site. The aim of the study was to identify typical tracers for different sources of organic aerosol and to determine their contributions to organic PM1.We found a clear difference between winter and summer PM1 aerosol composition at the molecular level. Subsequently, we identified two biogenic factors (dominant in summer), two anthropogenic factors (major contribution in winter) and one background factor.\nMore details could be found in Vodička et. al (2023).
Klíčová slova:
dicarboxylic acids; carbohydrates; fine aerosol
Plné texty jsou dostupné v digitálním repozitáři NUŠL
TRACERY ANTROPOGENNÍCH A BIOGENNÍCH ZDROJŮ ORGANICKÉHO AEROSOLU V PM1 FRAKCI NA POZAĎOVÉ STANICI KOŠETICE
V této studii jsme podrobně zkoumali sezónní změny koncentrace cukrů, dikarboxylových kyselin a jejich oxidačních prekurzorů v jemném aerosolu na venkovském středoevropském pozadí. Cílem studie bylo ...
PHYSICOCHEMICAL CHARACTERISTICS AND EVOLUTION OF AEROSOL FROM OPEN COMBUSTION OF BIOMASS DURING THE TRADITIONAL “BURNING OF THE WITCHES”
Mbengue, Saliou; Vodička, Petr; Komínková, Kateřina; Schwarz, Jaroslav; Zíková, Naděžda; Vítková, Gabriela; Windell, Laurence Christian; Suchánková, Lenka; Lhotka, Radek; Julaha, Kajal; Prokeš, Roman; Šmejkalová Holubová, A.; Ondráček, Jakub; Ždímal, Vladimír; Holoubek, Ivan
2023 - anglický
Open biomass burning (OBB) is a major source releasing large quantities of gaseous and particulate pollutants into the atmosphere, with global, regional and local impacts on air quality, public health and climate (Andreae, 2019, Chen et al., 2017). OBB aerosols mainly consist of carbonaceous matter, and a considerable amount of inorganic salts, which present distinctly different optical properties (Chen et al., 2017, Reid et al., 2005). In this study, we investigate the influence of OBB during the traditional Burning of the Witches (BoW), referred to in Czech as “Pálení čarodějnic”, on the physico-chemical properties of atmospheric aerosols collected at the National Atmospheric Observatory Košetice (NAOK). The BoW is a centuries-old pagan tradition very popular in the Czech Republic. Today, it is celebrated during the night from April 30 to May 1 by lighting bonfires made of woodpiles with fake witches.
Klíčová slova:
biomass burning; air pollution; size distribution; atmospheric ageing
Plné texty jsou dostupné v digitálním repozitáři Akademie Věd.
PHYSICOCHEMICAL CHARACTERISTICS AND EVOLUTION OF AEROSOL FROM OPEN COMBUSTION OF BIOMASS DURING THE TRADITIONAL “BURNING OF THE WITCHES”
Open biomass burning (OBB) is a major source releasing large quantities of gaseous and particulate pollutants into the atmosphere, with global, regional and local impacts on air quality, public health ...
PM1 UNDER THE MICROSCOPE: MULTI-ANNUAL AEROSOL OPTICAL PROPERTIES AND SIZE DISTIRBUTION OBSERVATION AT PERI-URBAN ATMOSPHERIC SITE ATOLL
Suchánková, Lenka; Bourrianne, E.; De Fillipi, R.; De Brito, J. F.; Riffault, V.; Prokeš, Roman; Holoubek, Ivan; Ždímal, V.; Crumeyrolle, S.
2023 - anglický
Atmospheric aerosols (AA) belong to short-lived climate forcers with high spatial and temporal variability. Although the radiative effects of AA are greatest on regional scales, changes in aerosol emissions can induce long-term global climate effects (Szopa et al., 2021). Thus, the measurement of aerosol properties is essential for better understanding of aerosol’s impact on health and climate. Although several international projects and platforms have been monitoring AA properties worldwide (GAW, WMO, ACTRIS, EMEP, EUCAARI, etc., Pandolfi et al., 2018), only PM10 or PM2.5 cutoff sizes have been used for measurements, and information about PM1 particles is missing. \nThe aim of this study is to present aerosol scattering properties with supporting data of absorption and particle number size distribution in PM1 in years 2018-2022 at peri-urban atmospheric site “Atmospheric Observations in LiLLE (ATOLL) in Lille, France. This study is the first to present results dedicated to aerosol scattering properties at this site.
Klíčová slova:
pm1; scattering coefficient; nephelometer; fossil fuel and biomass burning contribution; aethalometer; smps
Plné texty jsou dostupné v digitálním repozitáři Akademie Věd.
PM1 UNDER THE MICROSCOPE: MULTI-ANNUAL AEROSOL OPTICAL PROPERTIES AND SIZE DISTIRBUTION OBSERVATION AT PERI-URBAN ATMOSPHERIC SITE ATOLL
Atmospheric aerosols (AA) belong to short-lived climate forcers with high spatial and temporal variability. Although the radiative effects of AA are greatest on regional scales, changes in aerosol ...
Organoruthenium glycomimetics as selective galectin-1 inhibitors
Hamala, Vojtěch
2023 - anglický
The prepared organoruthenium glycomimetics demonstrated sin gle unit nanomolar affinity to Gal-1 and over four orders of magnitude\nhigher selectivity to Gal-1 in comparison to Gal-3. The organoruthe nium galectin inhibitors were found to be nontoxic to both cancer and\nnoncancerous cell lines. Selected complexes showed an in vitro an timigratory effect against invasive cancer cell lines MDA-MB-231 and\nSK-OV-3.
Klíčová slova:
galectin inhibitors; glycomimetcs; carbohydrates
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Organoruthenium glycomimetics as selective galectin-1 inhibitors
The prepared organoruthenium glycomimetics demonstrated sin gle unit nanomolar affinity to Gal-1 and over four orders of magnitude\nhigher selectivity to Gal-1 in comparison to Gal-3. The organoruthe ...
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