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N-alkylation of a lysergic acid derivative under PTC conditions in a continuous arrangement using sonication
Jaklová, Natalie
2023 - English
This contribution focuses on the application of sonication to the synthesis of a methyl ester of the 1-methyl-10α-methoxydihydrolysergic acid (MeLUME).
Keywords:
sonication; synthesis; methyl ester
Available in a digital repository NRGL
N-alkylation of a lysergic acid derivative under PTC conditions in a continuous arrangement using sonication
This contribution focuses on the application of sonication to the synthesis of a methyl ester of the 1-methyl-10α-methoxydihydrolysergic acid (MeLUME).
PROCESSING OF THE DATA MEASURED WITH CLOUD CONDENSATION NUCLEI COUNTER IN YEAR 2020 FOR SUBMISSION TO EBAS DATABASE
Moravec, Pavel; Jindra, Tomáš; Wagner, Zdeněk; Ždímal, Vladimír
2023 - English
Aerosol particles in the atmosphere that allow water vapor to condense and form cloud droplets are called Cloud Condensation Nuclei (CCN). Elevated concentrations of CCN tend to increase the concentration and decrease the size of cloud droplets. This can lead to suppression of precipitation in shallow and short-lived clouds and to greater convective overturning and more precipitation in deep convective clouds, Rose et al.(2010). The response of cloud properties and precipitation processes to increasing anthropogenic aerosol concentrations represents one of the largest uncertainties in the current understanding of climate change. One of the fundamental challenges is to determine the ability of aerosol particles to act as CCN under relevant atmospheric conditions. Knowledge of the spatial and temporal distribution in the atmosphere is essential to incorporate the effects of CCN into meteorological models of all scales, Huang et al. (2007). Long-term CCN measurements are performed at aerosol monitoring sites such as those forming ACTRIS (Aerosols, Clouds, and Trace Gases Research Infrastructure) network. Measured data are then submitted to the EBAS database, where they are available for the other ACTRIS researchers. In this paper, we present our experience with the processing of the data measured with CCNC for submission to the EBAS database. The data prepared for submission to EBAS from year 2020 are also presented.
Keywords:
atmospheric aerosols; CCNC; cloud condensation nuclei concentrations
Available in a digital repository NRGL
PROCESSING OF THE DATA MEASURED WITH CLOUD CONDENSATION NUCLEI COUNTER IN YEAR 2020 FOR SUBMISSION TO EBAS DATABASE
Aerosol particles in the atmosphere that allow water vapor to condense and form cloud droplets are called Cloud Condensation Nuclei (CCN). Elevated concentrations of CCN tend to increase the ...
DRONE-BASED VERTICAL MEASUREMENTS OF BLACK CARBON AEROSOLS AT A RURAL BACKGROUND AND AN URBAN SITE
Julaha, Kajal; Zíková, Naděžda; Ždímal, Vladimír
2023 - English
Black Carbon (BC) aerosols are primary particles emitted into the atmosphere as a by-product of incomplete combustion processes. BC absorbs solar radiation and altersthe radiation budget of the Earth(Bond et al., 2013). The radiative properties of BC heavily depend on its vertical profiles(Haywood and Ramaswamy, 1998). For example, BC in the free troposphere can enhance its radiative forcing by trapping energy emitted from lower cloud layers. \nThe modeling-based studies on BC vertical distribution are particularly poor (Chen et al., 2022), creating a need to measure the vertical distribution of BC on a regional scale,from areas characterized by anthropogenic emissions from the ground to those characterized by long-range transport(Ramana et al., 2010). Among all the other methods, drones have recently gained popularity because of their high-cost efficiency, flexibility, and mobility. Besides comparing BC aerosol vertical distribution at an urban and a regional background site, this study also calibrates drone measurements using a 230-meter tower.
Keywords:
vertical profile; drone; rural background
Available in a digital repository NRGL
DRONE-BASED VERTICAL MEASUREMENTS OF BLACK CARBON AEROSOLS AT A RURAL BACKGROUND AND AN URBAN SITE
Black Carbon (BC) aerosols are primary particles emitted into the atmosphere as a by-product of incomplete combustion processes. BC absorbs solar radiation and altersthe radiation budget of the ...
Simultaneous online determination of nitric acid and nitrates in ambient air
Alexa, Lukáš; Čmelíková, D.; Cigánková, Hana; Mikuška, Pavel
2023 - English
The innovated method for the simultaneous online determination of HNO3/NO3- in ambient air was developed. Due to high sensitivity of CLD (LOD = 5.1 nM in water solution, 3 s/n) no preconcentration method is required. The online methods were compared with the results obtained with the offline method based on sampling using filters and dry denuders (DD) covered by 0.5% NaF with subsequent analysis by ion chromatography (model ICS-2100, Dionex, USA) and capillary electrophoresis (model Agilent 7100, Agilent Technologies, USA).
Keywords:
nitric acid; nitrates; online analysis; CGU-ACTJU; CWEDD
Available in digital repository of the ASCR
Simultaneous online determination of nitric acid and nitrates in ambient air
The innovated method for the simultaneous online determination of HNO3/NO3- in ambient air was developed. Due to high sensitivity of CLD (LOD = 5.1 nM in water solution, 3 s/n) no preconcentration ...
Ambient organic aerosol origin at rural background site in the Czech Republic
Lhotka, Radek
2023 - English
Atmospheric aerosols (AA) are ubiquitous particles in the atmosphere that influence the Earth’s climatic system, environmental interactions, and human health. Among AA, great interest is dedicated to organic aerosols (OA) since it can represent from 20 to 90% of total submicron mass. Source apportionment of OA at background sites is one of the important tasks of current air quality protection.
Keywords:
organic aerosol; air quality protection; ural background site
Available in a digital repository NRGL
Ambient organic aerosol origin at rural background site in the Czech Republic
Atmospheric aerosols (AA) are ubiquitous particles in the atmosphere that influence the Earth’s climatic system, environmental interactions, and human health. Among AA, great interest is dedicated to ...
How can we best eliminate pharmaceuticals from wastewater?
Bourassi, Mahdi
2023 - English
Persistent pharmaceutical occurrence in different lakes and rivers usually originates from live stocks, agriculture, aquaculture, households, and hospitals. The presence of these compounds in the ecosystems leads to fatal consequences. Pharmaceuticals can threaten microorganisms in the environment, either causing its deterioration or allowing pathogens to gain resistance against antibiotics and medical treatments. These occurrences in the environment questions the ability of conventional treatment to remediate pharmaceutical wastewater.
Keywords:
wastewater; pharmaceuticals; membrane separation
Available in a digital repository NRGL
How can we best eliminate pharmaceuticals from wastewater?
Persistent pharmaceutical occurrence in different lakes and rivers usually originates from live stocks, agriculture, aquaculture, households, and hospitals. The presence of these compounds in the ...
Synthesis and cytotoxicity of fluorinated mannosamines
Krčil, Aleš
2023 - English
The aim of the project is to synthesise mono-, di- and trifluoroanalogs of N-acetylmannosamines. The cytotoxicity of the final products towards selected cancer cells will be determined. The key intermediates are the corresponding multiply fluorinated mannosazidethioglycosides prepared from deoxyfluorinated 1,6-anhydro-2-azidoβ-D-hexopyranose precursors by ring-opening reactions with phenyltrimethylsilyl sulfide.
Keywords:
synthesis; cytotoxicity; fluorinated mannosamines
Available in a digital repository NRGL
Synthesis and cytotoxicity of fluorinated mannosamines
The aim of the project is to synthesise mono-, di- and trifluoroanalogs of N-acetylmannosamines. The cytotoxicity of the final products towards selected cancer cells will be determined. The key ...
Chiral anion exchanger based on α-methylbenzylamine for enantioselective separation of racemic acids
Čížek, Jan
2023 - English
In this work, new enantioselective material based on α-methylbenzylamine as the chiral selector (recently utilized by our group in the preparation of chiral\nmembranes) covalently attached to Merrifield resin beads is proposed and discussed as a potentially cost-effective alternative to typically expensive stationary phase materials. It is shown that charged chiral methylbenzylamine works as an enantioselective anion exchanger potentially suitable for the separation of chiral acids, such as N–protected amino acid, or non-steroidal anti-inflammatory drugs (NSAID), such as ibuprofen. In a glass column chromatography experiment, racemic N–(tert–butoxycarbonyl) tryptophan was partially separated, reaching enantiomeric excess in eluates of around 10%.\n
Keywords:
chiral membranes; separation; racemic acids
Available in a digital repository NRGL
Chiral anion exchanger based on α-methylbenzylamine for enantioselective separation of racemic acids
In this work, new enantioselective material based on α-methylbenzylamine as the chiral selector (recently utilized by our group in the preparation of chiral\nmembranes) covalently attached to ...
Application of hydrodynamic cavitation in brewing
Štěrba, Jiří
2023 - English
The aim of this work is to apply these advantages in the brewery industry. In the field of beer brewing, we would like to investigate several phenomenona, such as the isomerization of bitter hop acids, the reduction of gluten concentration or the cell-walls breakdown.
Keywords:
brewery industry; hydrodynamic cavitation; experiments
Available in a digital repository NRGL
Application of hydrodynamic cavitation in brewing
The aim of this work is to apply these advantages in the brewery industry. In the field of beer brewing, we would like to investigate several phenomenona, such as the isomerization of bitter hop ...
Intercomparison of boundary layer and mixing layer height from models and ground-based measurements
Julaha, Kajal
2023 - English
In this study, we found that the boundary layer height tends to belower in ERA5 and timing for the daily peak also appears to differ\nas compared to ceilometer boundary layer data. In contrast, the ERA5 boundary layer observation was found to agree well with the mixing layer height obtained from the ceilometer. Whereas in comparison to HYSPLIT, GFS and GDAS, observations were found to agree well with ceilometer data while Reanalysis underestimated mixing layer height throughout the year. The seasonal changes in the boundary/mixing layer height were well captured by both models and the ceilometer.
Keywords:
planetary boundary layer; air pollution; measurements
Available in a digital repository NRGL
Intercomparison of boundary layer and mixing layer height from models and ground-based measurements
In this study, we found that the boundary layer height tends to belower in ERA5 and timing for the daily peak also appears to differ\nas compared to ceilometer boundary layer data. In contrast, the ...
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