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Fluorimetric Determination of Scandium
Holubová, Zuzana ; Komendová, Renata (referee) ; Sommer, Lumír (advisor)
The submitted thesis deals within the sensitive fluorimetric determination of scandium with a new reagent 8-Hydroxyquinoline-5-sulphonic acid. All important factors such as time, pH, reagent concentration, buffers, surfactants and selected interferents have been studied with respect to the selectivity, sensitivity, precision and detection limit on the determination by using classic fluorescence spectra and their first derivation. This reagent was also used for the determination of scandium in real waters. The new reagent was shortly compared to morin and lumogallion when used for scandium.
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Processing of Al-Sc aluminum alloy using SLM technology
Skulina, Daniel ; Náhlík, Luboš (referee) ; Koutný, Daniel (advisor)
Master's thesis deals with the experimental determination of process parameters reaching densities >99 % for scandium modified aluminium alloy (Scalmalloy®) processed by SLM. The alloy achieves higher mechanical properties than the AlSi10Mg aluminum alloy commonly used. The theoretical part deals mainly with the results of Scalmalloy® alloys. Experimental bodies, testing methodology and evaluation method were designed on the basis of the theoretical parts,. The practical part is divided into four main stages: experimental determination of process parameters, a description of the effect of the parameters used on the relative density achieved, examination of the influence of process parameters on surface quality and mechanical testing. The mechanical properties were determined for the best parameters.
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Preparation and Characterization of Iron (III) Oxide Nanocomposites Substituted with Scandium
Kaščáková, Dorota ; Nižňanský, Daniel (advisor) ; Tyrpekl, Václav (referee)
In this work a preparation and characterization of nanoparticles of iron(III) oxide substituted with scandium in SiO2 matrix is described. The nanoparticles were prepared by the sol-gel method yielding mostly β-Fe2O3 substituted with various amount of scandium(III) ions. Mossbauer spectroscopy was carried out to determine purity of the samples and the content of other iron oxides phases. System was characterized by magnetic measurements. Powder X - ray diffraction was used to verify the composition and to determine the lattice parameter and particle size. β-Fe2O3 is formed at the temperatures of 1000 and 1100 ◦ C at composition Fe2−xScxO3 for x ≥ 0.2 and at temperature 1100 ◦ C for x = 0.1. Lattice parameter is linearly dependent on the scandium content and depends also on the annealing temperature. At temperatures higher than 1250 ◦ C, β-Fe2O3 is transformed into hematite. Key words: iron(III) oxide, scandium, sol-gel, Mossbauer spectroscopy, X-ray diffraction, magnetic measurements 1
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Preparation and Characterization of Iron (III) Oxide Nanocomposites Substituted with Scandium
Kaščáková, Dorota ; Nižňanský, Daniel (advisor) ; Tyrpekl, Václav (referee)
In this work a preparation and characterization of nanoparticles of iron(III) oxide substituted with scandium in SiO2 matrix is described. The nanoparticles were prepared by the sol-gel method yielding mostly β-Fe2O3 substituted with various amount of scandium(III) ions. Mossbauer spectroscopy was carried out to determine purity of the samples and the content of other iron oxides phases. System was characterized by magnetic measurements. Powder X - ray diffraction was used to verify the composition and to determine the lattice parameter and particle size. β-Fe2O3 is formed at the temperatures of 1000 and 1100 ◦ C at composition Fe2−xScxO3 for x ≥ 0.2 and at temperature 1100 ◦ C for x = 0.1. Lattice parameter is linearly dependent on the scandium content and depends also on the annealing temperature. At temperatures higher than 1250 ◦ C, β-Fe2O3 is transformed into hematite. Key words: iron(III) oxide, scandium, sol-gel, Mossbauer spectroscopy, X-ray diffraction, magnetic measurements 1
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Processing of Al-Sc aluminum alloy using SLM technology
Skulina, Daniel ; Náhlík, Luboš (referee) ; Koutný, Daniel (advisor)
Master's thesis deals with the experimental determination of process parameters reaching densities >99 % for scandium modified aluminium alloy (Scalmalloy®) processed by SLM. The alloy achieves higher mechanical properties than the AlSi10Mg aluminum alloy commonly used. The theoretical part deals mainly with the results of Scalmalloy® alloys. Experimental bodies, testing methodology and evaluation method were designed on the basis of the theoretical parts,. The practical part is divided into four main stages: experimental determination of process parameters, a description of the effect of the parameters used on the relative density achieved, examination of the influence of process parameters on surface quality and mechanical testing. The mechanical properties were determined for the best parameters.
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Fluorimetric Determination of Scandium
Holubová, Zuzana ; Komendová, Renata (referee) ; Sommer, Lumír (advisor)
The submitted thesis deals within the sensitive fluorimetric determination of scandium with a new reagent 8-Hydroxyquinoline-5-sulphonic acid. All important factors such as time, pH, reagent concentration, buffers, surfactants and selected interferents have been studied with respect to the selectivity, sensitivity, precision and detection limit on the determination by using classic fluorescence spectra and their first derivation. This reagent was also used for the determination of scandium in real waters. The new reagent was shortly compared to morin and lumogallion when used for scandium.
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