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Comparison of Summer and Winter Highly Time-Resolved Submicron Aerosol Composition Measured at a Suburban Site in Prague
Kubelová, Lucie
We analyzed c-ToF-AMS data from a summer (20. 6.–31. 7. 2012) and winter (8. 1.–19. 2. 2013) measurement campaign at a suburban site Prague-Suchdol. The observed chemical composition with dominating organics in both seasons was in accordance with previous measurements at this site.The modal diameter of size distribution occurred at higher values during episodes of increased total concentration and decreased temperature. Furthermore, we compared the AMS data with organic carbon elemental carbon field analyzer (OC/EC) measurement. This comparison together with analysis of particular organic fragments revealed that winter aerosol was less oxidized and more influenced by biomass burning. Such characteristics point to an influence of local domestic heating in winter.
Fulltext: content.csg - PDF Plný tet: SKMBT_C22015061709390 - PDF
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Novel NMR Method for Organic Aerosol Analysis
Horník, Štěpán
The suitability of ChenomX was performed both on real atmospheric aerosols and model samples of coal combustion. Up to 30 compounds were found in analyzed samples. Most abundant substances were mono- and dicarboxylic acids (formic, acetic, succinic acid) and their derivatives (lactic acid), followed by carbohydrates, anhydro saccharides and sugar alcohols (levoglucosan, fructose, D-threitol), and amines (methylamine, dimethylamine). The real aerosol sample was also analyzed on four different NMR spectrometers (500, 600, 700, 800 MHz) in order to enhance the resolution and find less abundant substances. The frequencies of the spectrometers were chosen according to the ChenomX database. In the 800 MHz spectrum ca. 50 compounds were identified.
Fulltext: content.csg - PDF Plný tet: SKMBT_C22015061709380 - PDF
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Analytical Features of the Optical Biosensor for Glucose Detection
Maixnerová, Lucie
The first aim of my work was to determine boundaries of the above-mentioned parameters as maxima and minima of the weight (thickness) of the layer and the quantity of the immobilized enzyme. Glucose oxidase from Aspergilus niger (37.7 KU⋅g−1 solid) immobilized on Sepabeads® (SPB) coated together with the ruthenium oxygen sensitive complex in the organic-inorganic polymer ORMOCER® were used in all experiments. From process parameters maxima and minima concentrations of oxygen and glucose were detected. The second aim was to prepare biosensors with substantially diverse analytical characteristics via combinations of these parameters. The obtained experimental data will be a base for a detailed mathematical model of MATINOES biosensors (outlined in our previous paper1), which we are going to develop in the collaboration with ICT Prague. This model should enable a preparation of MATINOES biosensors with tailor-made analytical features.
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Influence of Structure of Ionic Liquids on the Properties of their Mixtures with Water
Rotrekl, Jan
This contribution reports on a part of the results of a project focused on imidazolium-based ILs with a bis{(trifluoromethyl)sulfonyl}imide anion. The choice of the studied ILs is motivated by a study of the influence of the cation structure on the physico-chemical properties of pure ionic liquids and their mixtures with molecular solvents. For this purpose, four isomeric ILs, namely 1-alkyl-3-butylimidazolium bis{(trifluoromethyl) sulfonyl}imides (abbreviated [C4xC5im][Tf2N], alkyl = pentyl, isopentyl, 3-pentyl, or cyclopentyl) were selected. In a previous work, fundamental physico-chemical properties such as density, isobaric heat capacity, viscosity, electrical conductivity were measured.2 In this part of the study, the properties of the studied range of ILs in systems with water were investigated.
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Progress in Helicene Stationary Phases
Cerhová, Marie
The motivation of this work is to utilize the SFE for the direct preparation of highly pure TiO2 thin films without any subsequent thermal processing. Extraction with pure and modified scCO2 was tested and compared with PLE. Different types of liquid solvents (water, ethanol, acetone etc.) were used as scCO2 modifiers at concentrations from 0 to 30 mass %. The effect of extraction temperature (40–150 °C), pressure (10–65 MPa) and the volume (50–200 g) and flow rate (0.3–1.8 g/min) of solvents passed through the extractor on microstructure and purity of TiO2 thin films were examined.
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