National Repository of Grey Literature 16 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
Co-Mn-Al mixed oxides promoted for direct NO decomposition: preparation and properties.
Jirátová, Květa ; Pacultová, K. ; Balabánová, Jana ; Karásková, K. ; Klegová, A. ; Bílková, T. ; Jandová, Věra ; Koštejn, Martin ; Martaus, A. ; Kotarba, A. ; Obalová, L.
The catalysts investigated in this work were prepared by co-precipitation of nitrates with aqueous K2CO3/KOH solution, followed by washing the precipitates to varying degrees of potassium content and calcining the precursors at 500 °C for 4 h. Mn-Al potassium salt followed by calcination at 500 °C. Before the catalytic reaction, they were calcined at 700 °C. The catalysts and their precursors were characterized by the following measurement techniques: ICP, DTG, XRD, N2 physisorption, FTIR, H2-TPR, CO2-TPD, XPS, and thermal alkali metal desorption (SR-TAD).\n\n
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Pulsed Laser Deposition under Low Background Gas Pressure.
Koštejn, Martin ; Fajgar, Radek ; Dřínek, Vladislav ; Jandová, Věra ; Klementová, Mariana ; Bakardjieva, Snejana
The nucleation of nanoparticles was applied during gold deposition onto TiO2 layers. For nucleation, up to 10 Pa of inert gas (argon) was used. Argon molecules efficiently helped to cool temperature of evolving plume and initiated the nucleation which resulted in deposition of gold nanoislands. Gold nanoparticles incorporated in TiO2 layers provided plasmonic properties. Au/TiO2 layers were used for water splitting as proved by photoelectrochemical measurements.
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Preparation of Chitosan Based Films for Food Packaging Applications.
Soukup, Karel ; Cruz, G.J.F. ; Hanika, Jiří ; Jandová, Věra ; Hejtmánek, Vladimír ; Šolcová, Olga
In the present study, the effect both of the botanical source and proportion of starch produced from agricultural surplus on the microstructure properties of starch/chitosan/glycerin films was tested. Effective gas transport properties gas diffusion transfer was performed. Starch/chitosan/glycerol biodegradable films were obtained by casting method from giant squid (Dosidicus gigas) pen chitosan mixed with glycerin and starch. Four starch samples were prepared using exceeding or low quality biomass including broken rice grains, hard yellow corn surplus, banana surplus form exportation activity and low quality cassava in three different weight proportion (chitosan/starch) corresponding to 1/1, 2/1 and 5/1. Extraction of starch from the raw material was carried out by mixing it with a water solution of sodium disulfite (5 wt.%). Afterwards, the obtained suspension was filtered and then decanted at 5°C for 24 h. The obtained starch was washed repeatedly with distilled water and ethanol (96 vol.%). Finally, the starch samples were dried at 55°C for 48 h, crushed and sieved. It was found that the gas diffusion transport properties significantly depend on the starch source used. Differences in diffusion transport rates through the films prepared with different starches are related to the size and distribution of granules of starch in the films and/or the amylose conten.
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Regeneration of TFC PA Membrane Used for Permation of Hexane Vapours.
Petrusová, Zuzana ; Morávková, Lenka ; Štefková, V. ; Machanová, Karolina ; Jandová, Věra ; Koštejn, Martin ; Izák, Pavel ; Jansen, J.
This contribution is accomplished by the study of the membrane affinity via contact angle measurements and by structural analysis via electron he transport properties of the TFC PA were studied at various experimental conditions and the obtained results will be discussed.
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Influence of Water-Ethanol-Modified Supercritical Carbon Dioxide at the Preparation of Crystalline Monolithic TiO2 Aerogels.
Cerhová, Marie ; Sajfrtová, Marie ; Matějová, L. ; Dřínek, Vladislav ; Daniš, S. ; Jandová, Věra
This work is focused on a 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 modifie concentration in scCO2 (5-15 wt.%) and the additional drying with pure CO2 on microstructure, purity and textural properties of TiO2 aerogel was investigated. Processed monoliths were characterized by XRD analysis, Raman spectroscopy and N2 physisorption.
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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.
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Use of Water- And Ethanol-Modified Supercritical Carbon Dioxide for Direct Preparation of Crystalline Monolithic TiO2 Aerogels.
Cerhová, Marie ; Sajfrtová, Marie ; Matějová, L. ; Dřínek, Vladislav ; Daniš, E. ; Jandová, Věra
We studied a combination of supercritical CO2, water and ethanol for the preparation of crystalline and pure nanostructured TiO2 without any thermal processing. The effect of temperature (40-150 °C) and sequence on structural and textural properties was investigated at constant pressure of 30 MPa. The prepared aerogels were characterized with respect to the (micro)structural properties by Raman spectroscopy and X-ray diffraction. The textural properties such as specific surface area, content of mesoporous and volume of microporous were determined from nitrogen physisorption and skeletal density by helium pycnometry measurements.
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National Repository of Grey Literature : 16 records found   1 - 10next  jump to record:
See also: similar author names
8 JANDOVÁ, Veronika
2 JANDOVÁ, Václava
8 Jandová, Veronika
2 Jandová, Vilma
2 Jandová, Václava
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