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Metodika identifikace zdrojů znečišťování pomocí PMF pro strategické rozhodování při ochraně ovzduší – aktualizace 2023
Horník, Štěpán; Sýkora, Jan; Pokorná, Petra
2023 - Czech
Předkládaná metodika navrhuje využití spektroskopie nukleární magnetické rezonance (NMR) jako další analytické techniky pro identifikaci sloučenin v atmosférických aerosolech. Tato technika umožňuje výrazně zvýšit počet stanovovaných látek a tfm i případný počet markerů, které lze následně ve spojení s jinými metodami využít pro identifikaci zdrojů znečištění ovzduší pomocí pokročilé statistické analýzy. Mezi markery stanovované pomocí\nNMR spektroskopie náleží různé organické kyseliny, sulfonové kyseliny nebo sacharidy, které jsou charakteristické pro příslušné zdroje znečištění. Aktualizovaná metodika také představuje identifikaci biogenního zdroje, který předcházející metodiky nedokázaly stanovit. The presented methodology proposes utilizatíon of the spectroscopy of nuclear magnetic resonance (NMR) as another analytical technique for the identification of compounds in atmospheric aerosols. This technique makes significantly increases the number of deterined substances and thus a number of possible markers, which can be subsequently used together with other methods to identify sources of air pollution using advanced statistical\nanalysis. Among the markers determined by NMR spectroscopy there are several organic and sulfonic acids or carbohydrates, wich are characteristic for relevant sources of air pollution. The updated methodology also shows the identification of a biogenic source that previous methodologies were not able to determine.
Keywords:
NMR spectroscopy; atmospheric aerosols; markers
Available on request at various institutes of the ASCR
Metodika identifikace zdrojů znečišťování pomocí PMF pro strategické rozhodování při ochraně ovzduší – aktualizace 2023
Předkládaná metodika navrhuje využití spektroskopie nukleární magnetické rezonance (NMR) jako další analytické techniky pro identifikaci sloučenin v atmosférických aerosolech. Tato technika umožňuje ...
Utilization of electrochemically induced cleavage of various sulfonimides
Salvadori, Karolína
2023 - English
In this work, we describe the unexpected electrochemical cleavage of sulfonimides, providing a direct pathway to corresponding sulfonamides. For this purpose, 16 substances were synthesized and tested, reflecting the influence of different electron effects of -SO2Ph-R substituents, and the impact of the number of nosyl units present in molecules. In the case of octakis-nosylated calixarenes, the electrochemical cleavage via direct potential-controlled electrolysis was compared with conventional organic synthetic procedures. After electrolysis, all prepared sulfonamides were isolated in excellent yields.
Keywords:
sulfonimides; green chemistry procedures; electrochemisty
Available in a digital repository NRGL
Utilization of electrochemically induced cleavage of various sulfonimides
In this work, we describe the unexpected electrochemical cleavage of sulfonimides, providing a direct pathway to corresponding sulfonamides. For this purpose, 16 substances were synthesized and ...
Green approach for the preparation of biosourced ionic liquids and the study of their thermodynamic properties\n
Souvenir Zafindrajaona, Mahasoa-Salina
2023 - English
This presentation will address a green approach to the synthesis of ionic liquids qualified as biosourced (monocatenar or bolaform systems) from specific agro-resources, according to several principles of green chemistry. As these solvents could be used to solubilize lignocellulosic biomass and/or extract bioactive compounds (from plant sourcing), the physicochemical characteristics (density, viscosity and heat capacity) of pure ILs or mixtures of IL/water must be determined. Preliminary results concerning this last point will be presented.
Keywords:
biosourced ionic liquids; lignocellulosic biomass; thermodynamic properties
Available in a digital repository NRGL
Green approach for the preparation of biosourced ionic liquids and the study of their thermodynamic properties\n
This presentation will address a green approach to the synthesis of ionic liquids qualified as biosourced (monocatenar or bolaform systems) from specific agro-resources, according to several ...
Cultivation of Limnospira maxima and utilization of its fresh biomass in human nutrition
Vásquez, Claudia
2023 - English
This work aims to enhance productivity, efficiency and sustainability of L. maxima cultivation as well as to determine the safe microbiological conditions for the nutritional use of fresh spirulina biomass. Various parameters such as light intensity, light spectral composition, temperature, pH, CO2, and culture media composition can be optimized. A series of experiments were performed to find the most suitable configuration to cultivate L. maxima, defined by cyanobacterium productivity and yield as well as other metabolites production such as phycocyanin (C-PC) and carotenoids.
Keywords:
Limnospira maxima; fresh biomass; human nutrition
Available in a digital repository NRGL
Cultivation of Limnospira maxima and utilization of its fresh biomass in human nutrition
This work aims to enhance productivity, efficiency and sustainability of L. maxima cultivation as well as to determine the safe microbiological conditions for the nutritional use of fresh spirulina ...
Organic fluorine content and change during thermal treatmen
Hušek, Matěj
2023 - English
We have previously described how pyrolysis affected the content of selected PFAS representatives.4,5 However, we could not determine with certainty whether they were merely cleaved or mineralised. Therefore, we focused on the change in organic fluorine content (part of PFAS) and analysed its thermal behaviour in inert (sea sand) and heterogeneous (sewage sludge) material.
Keywords:
organic fluorine; sewage sludge; thermal treatment
Available in a digital repository NRGL
Organic fluorine content and change during thermal treatmen
We have previously described how pyrolysis affected the content of selected PFAS representatives.4,5 However, we could not determine with certainty whether they were merely cleaved or mineralised. ...
Separation of exosomes from polydisperse suspension in microfluidic devices
Paříková, Anna
2023 - English
The work included fine-tuning the experimental methodology, writing an in-house code for exosome tracking based on a one-way\napproach, and performing a parametric study to investigate the separation potential of the microdevice as a function of channel geometry, flow rate, and viscosity. Preliminary results show that viscoelasticmicrofluidics can be used as an alternative to conventional e xosome separation techniques.
Keywords:
separation techniques; exosomes; microfluidic devices
Available in a digital repository NRGL
Separation of exosomes from polydisperse suspension in microfluidic devices
The work included fine-tuning the experimental methodology, writing an in-house code for exosome tracking based on a one-way\napproach, and performing a parametric study to investigate the separation ...
Závěrečná zpráva o využití membránové separace solí obsahujících sírany a chloridy typických kovů z průmyslových vod
Šyc, Michal; Veselý, Václav
2023 - Czech
Cílem spolupráce bylo ověřit možné využití membránových procesů pro získávání kovů nebo jejich hydroxidů a to nejlépe v separované formě. Jako základní membránovou metodu bude-me uvažovat elektrodialýzu/elektrokoagulaci. Procesy budou ověřeny na třech typických druhů promyslových odpadních vod. Prvním druhem jsou průsakové vody, druhým pak průmyslové vody z technologie povrchových úprav a třetím pak jsou vody technologické z hydrometalur-gického zpracování odpadů. Cílem není návrh technologie na finální úpravu průmyslových odpadních vod. The aim of the collaboration was to verify the possible use of membrane processes for the recovery of metals or their hydroxides, preferably in separated form. As a basic membrane method we will consider electrodialysis/electrocoagulation. The processes will be validated on three typical types of industrial wastewater. The first type is leachate, the second is industrial water from surface treatment technology and the third is process water from hydrometallurgical waste treatment. The aim is not to design a technology for the final treatment of industrial wastewater.
Keywords:
membrane processes; industrial wastewater; metal hydroxides
Available at various institutes of the ASCR
Závěrečná zpráva o využití membránové separace solí obsahujících sírany a chloridy typických kovů z průmyslových vod
Cílem spolupráce bylo ověřit možné využití membránových procesů pro získávání kovů nebo jejich hydroxidů a to nejlépe v separované formě. Jako základní membránovou metodu bude-me uvažovat ...
Hazardous components: A case study in textile waste management
Shtukaturova, Anastasia
2023 - English
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.
Keywords:
textile waste; waste management; chemicals
Available in a digital repository NRGL
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 - English
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.
Keywords:
biochar; particle size on biochar; high-temperature biochar
Available in a digital repository NRGL
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 - English
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.
Keywords:
aerosols; analytical methods; chemical composition
Available in a digital repository NRGL
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 ...
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