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Detection of luminescent nanoparticles in plants by laser spectroscopy
Střítežská, Sára ; Novotný,, Karel (referee) ; Modlitbová, Pavlína (advisor)
This diploma thesis deals with evaluation of toxicity and bioaccumulation of photon-upconversion nanoparticles (UCNPs) in model plant maize (Zea mays). Lanthanide-doped UCNPs with different composition and size were tested in three different concentrations in this work. The exposure took place for 168 hours. Toxicity was assessed based on four macroscopic toxicological endpoints (mortality, the length of belowground part of the plants, the length of aboveground part of the plants and whole plants length). Spatial distribution of elements yttrium, ytterbium, erbium and gadolinium in model plants was determined using laser induced breakdown spectroscopy with spatial resolution of 100 m and 26 m. Distribution of UCNPs in plants was further studied with photon-upconversion microscanning with spatial resolution of 40 m. Stability of UCNPs during and after the plant exposure was also discussed in this thesis.
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Nuclear Fuel in Operational Conditions
Konopová, Tamara ; Novotný, Filip (referee) ; Katovský, Karel (advisor)
This thesis deals with the issue of nuclear fuel. Firstly, the problem of nuclear fuel in the implementation for certain reactors is presented. Production of nuclear fuel is introduced, which includes the performance of companies engaged in the production of this fuel. Secondly, the phenomena in the fuel burnup are discussed. Lastly, the burnable absorbers are mentioned and the analysis of burnable absorbers is carried out.
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Nuclear Fuel in Operational Conditions
Konopová, Tamara ; Novotný, Filip (referee) ; Katovský, Karel (advisor)
This thesis deals with the issue of nuclear fuel. Firstly, the problem of nuclear fuel in the implementation for pressurized water reactors is presented. Production of nuclear fuel is introduced, which includes the performance of companies engaged in the production of this fuel. Secondly, problems of nuclear fuel during operation, focusing on burnable absorbers and phenomena in the fuel burnup are discussed. Lastly, the calculation is carried out and gadolinium as a burnable absorber is compared with erbium as a burnable absorber.
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Detection of luminescent nanoparticles in plants by laser spectroscopy
Střítežská, Sára ; Novotný,, Karel (referee) ; Modlitbová, Pavlína (advisor)
This diploma thesis deals with evaluation of toxicity and bioaccumulation of photon-upconversion nanoparticles (UCNPs) in model plant maize (Zea mays). Lanthanide-doped UCNPs with different composition and size were tested in three different concentrations in this work. The exposure took place for 168 hours. Toxicity was assessed based on four macroscopic toxicological endpoints (mortality, the length of belowground part of the plants, the length of aboveground part of the plants and whole plants length). Spatial distribution of elements yttrium, ytterbium, erbium and gadolinium in model plants was determined using laser induced breakdown spectroscopy with spatial resolution of 100 m and 26 m. Distribution of UCNPs in plants was further studied with photon-upconversion microscanning with spatial resolution of 40 m. Stability of UCNPs during and after the plant exposure was also discussed in this thesis.
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Nuclear Fuel in Operational Conditions
Konopová, Tamara ; Novotný, Filip (referee) ; Katovský, Karel (advisor)
This thesis deals with the issue of nuclear fuel. Firstly, the problem of nuclear fuel in the implementation for certain reactors is presented. Production of nuclear fuel is introduced, which includes the performance of companies engaged in the production of this fuel. Secondly, the phenomena in the fuel burnup are discussed. Lastly, the burnable absorbers are mentioned and the analysis of burnable absorbers is carried out.
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Nuclear Fuel in Operational Conditions
Konopová, Tamara ; Novotný, Filip (referee) ; Katovský, Karel (advisor)
This thesis deals with the issue of nuclear fuel. Firstly, the problem of nuclear fuel in the implementation for pressurized water reactors is presented. Production of nuclear fuel is introduced, which includes the performance of companies engaged in the production of this fuel. Secondly, problems of nuclear fuel during operation, focusing on burnable absorbers and phenomena in the fuel burnup are discussed. Lastly, the calculation is carried out and gadolinium as a burnable absorber is compared with erbium as a burnable absorber.
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Fotoluminiscence erbiem dopovaných krystalů KTaO.sub.3./sub..
Potůček, Zdeněk ; Bryknar, Z. ; Trepakov, Vladimír
Photoluminescence emission spectra of KTaO3:Er crystals was studied within the wide temperature (12 – 300 K) and spectral (300 – 1200 nm) regions in order to reveal luminescence centers related to Er ions and to elucidate their optical properties. Under excitation with band-gap light at low temperatures, the KTaO3:Er crystals shoved a broad asymmetric emission band peaking near 490 nm at 12 K that belongs to well-known “green” photoluminescence of KTaO3 crystals. Erbium doping was accompanied by appearance of narrow structured emission bands in the vicinity of 550, 660, and 850 nm that were attributed to radiative transitions within Er3+ ions with 4f11 electron configuration.
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