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Effect of Conditions on TiO2 Aerogel Crystallization Using Modified Supercritical Carbon Dioxide.
Cerhová, Marie
This work is focused on a deeper study of TiO2 aerogel SFC with scCO2 modified by mixture of ethanol and water in a ratio 1:1. The effect of temperature (40–100 °C), pressure (10–30 MPa) and modifier concentration in scCO2 (5–15 wt.%) on microstructure, purity and textural properties of TiO2 aerogel was investigated. Processed monoliths were characterized by XRD analysis, Raman spectroscopy and N2 physisorption.
Plný tet: SKMBT_C22018060408160 - PDF Plný text: content.csg - PDF
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Supercritical Fluid Extraction of Sesquiterpene Lactones from Laserpitium archangelica.
Sajfrtová, Marie ; Kraus, V. ; Wimmer, Z. ; Cerhová, Marie ; Vlk, M.
The aim of the work was to describe the SFE of two STLs, archangelolide and trilobolide, from seeds of Laserpitium archangelica (Apiaceae). The objectives consisted in: (a) optimizing, investigating the SFE condition (pressure, temperature and concentration ofmodifier in scCO2) effect on the yield and concentration of STLs in extract, (b) \nDetermination of the SFE kinetics of major components in the extracts and (c) comparing the SFE with pressurised liquid extraction (PLE) and Soxhlet extraction.\n\n\n
Plný tet: SKMBT_C22018100509461 - PDF Plný text: content.csg - PDF
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Non-Thermal Crystallization of TiO2 Thin Films using Supercritical Carbon Dioxide Modified by Ethanol-Water Mixture.
Sajfrtová, Marie ; Cerhová, Marie ; Jandová, Věra ; Dřínek, Vladislav ; Matějová, L. ; Daniš, S.
In this work, the scCO2 modified by mixture of water and ethanol was used for a preparation of crystalline and pure nanostructured TiO2 thin films in one step processing. All the experiments were performed over precursor titania thin films prepared by reverse micelles assisted sol-gel method, using hardly removable nonionic surfactant Triton X-114, however, forming uniform nano-domains. The effect of temperature (40-150 °C), pressure (10-30 MPa), modifier composition \n(20, 50 and 80 % w/w of water in ethanol) and concentration inscCO2 (5-15 wt. %) and consumed amount of solvent (50-200 g) on microstructure and purity\nof TiO2 thin films was thoroughly studied by means of Raman spectroscopy, X-ray diffraction, and contact angle measurements.
Plný tet: SKMBT_C22018100509361 - PDF Plný text: content.csg - PDF
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