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Element analysis of magnesium alloys using laser induced breakdown spectrometry
Veis, Samuel ; Fintová, Stanislava (referee) ; Doležal, Pavel (advisor)
Bachelor‘s thesis is aimed at assessing the possibilities of trace elements detection in magnesium alloys using laser induced breakdown spectroscopy with a focus on rare earth elements. Base materials were wrought magnesium alloy sheet ZE10 with thickness of 1,6 mm and ZE41 with thickness of 2 mm produced using Direct Chill casting method. Qualitative and quantitative ways of LIBS spectra evaluation were described in the work. Qualitative analysis confirmed the presence of La, Ce, Nd and Pr in ZE41, and La with Ce in ZE10. These informations confirm results of EDS analysis. For a demonstration, quantitative analysis of ZE10 was made, which confirmed the possibility of using LIBS for detection of REE in Mg alloys.
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The effect of yttrium and samarium oxide nanoparticles on plant development
Brandová, Zuzana ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
This thesis is based on hydroponic experiment conducted on Hordeum vulgare with nanoparticles of rare earth elements in concentration 2·10-4 mol/L and REEs chlorides in concentration 3·10-4 mol/L. The comparison of the the effect on their acumulation of another nanoparticles in the sloution and normal medium is included as well. In this case the hydroxyapatite NPs were chosen in the same concentration as yttrium and samarium NPs. The role of type and form of the elements on their acumulation and impact is also studied. Negative effect of REEs was proven by enzymatic analysis that detects reducting enzymes and determination of plant pigment levels by high performance liquid chromatography. Because both types of substances can reduce reactive oxygen radicals. Acumulation of REEs was determined by ICP spektrometry. Key words: nanoparicles, reare earth elements, reductive enzymes, plant pigments, acumulation, oxidative stress
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Recycling modern cars
Borik, Matúš ; Charvát, Pavel (referee) ; Štětina, Josef (advisor)
Zem čelí nadmernému prekračovaniu recyklačných limitov organických a anorganických surovín, čo spôsobuje nedostatočnú absorpciu skleníkových plynov. Automobilový priemysel sa v posledných desaťročiach rapídne rozbehol a má na tom svoj podiel. Významný negatívny vplyv na rast výroby automobilov má ťažba zdrojov, ktorá prináša niekoľko environmentálnych problémov, ako je vyčerpanie zdrojov, neudržateľnosť životného prostredia, ktorá vedie ku globálnemu otepľovaniu, a zdravotné problémy spojené s ťažbou zdrojov a výrobou automobilov. Ak sa má udržať úroveň používania automobilov, hlavným riešením je zamerať sa na recykláciu a výrobu ekologických vozidiel. Výskum recyklačných metód moderných vozidiel a ich analýza je zameraním tejto bakalárskej práce, ktorej konkrétnym cieľom poskytnúť náhľad rôznych typov recyklačných postupov. Prvá časť sa zaoberá všeobecnými princípmi recyklácie a recykláciou vozidiel po častiach. Následne práca presúva svoju pozornosť na obnoviteľné zdroje a ich využitie v automobilovom priemysle (elektromobily) a recykláciu moderných automobilov vyradených z prevádzky. Posledná časť prináša bližší pohľad na možnosti skladovania energie z obnoviteľných zdrojov, špecificky na vodíka (H2), jeho využitie v palivových článkoch, recykláciu vodíkových automobilov a budúcnosť pohonu. Práca konzultovaná s expert inžinierom danej oblasti.
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Rare earth elements in electronic waste
Pospíšilová, Eliška ; Šebek, Ondřej (advisor) ; Strnad, Ladislav (referee)
Rare earth elements consist of 15 lanthanides, Y and Sc. They are currently very important materials in many industrial branches (metalurgy, pollishing). One of these options is the usage as the compound of phosphors in electronic devices (television and computer displays. Because of their manufacturing cost, options of recovery from waste electrical and electronic equipment (WEEE) are investigated. This thesis deals with compoud elements of phosphors from displays of type CRT (cathode ray tube) and plasma TV. The 37 samples of phosphors from different displays were taken and processed for study of the compoud elements. Phosphors were separated to 4 subgroups in accordance with the corresponding type of displays: black-and-white CRT television displays (CRT_CB), color CRT television displays (TV_B), color PC displays (PC_B) and monochromatic PC displays (PC_M). The study was carry out by multiple features analysis that combined the inductively coupled plasma mass spectrometry (ICP-MS), the inductively coupled plasma optical emission spectrometry (ICP-OES), the resistance furnace with infrared detector (RF-IF) and the atomic absorption spectrometry (AAS). Based on the results of this analysis, main elements and potentionally hazardous elements of phosphors subgroup were defined. Concentration of rare...
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Rare earth elements in electronic waste
Pospíšilová, Eliška ; Šebek, Ondřej (advisor) ; Strnad, Ladislav (referee)
Rare earth elements consist of 15 lanthanides, Y and Sc. They are currently very important materials in many industrial branches (metalurgy, pollishing). One of these options is the usage as the compound of phosphors in electronic devices (television and computer displays. Because of their manufacturing cost, options of recovery from waste electrical and electronic equipment (WEEE) are investigated. This thesis deals with compoud elements of phosphors from displays of type CRT (cathode ray tube) and plasma TV. The 37 samples of phosphors from different displays were taken and processed for study of the compoud elements. Phosphors were separated to 4 subgroups in accordance with the corresponding type of displays: black-and-white CRT television displays (CRT_CB), color CRT television displays (TV_B), color PC displays (PC_B) and monochromatic PC displays (PC_M). The study was carry out by multiple features analysis that combined the inductively coupled plasma mass spectrometry (ICP-MS), the inductively coupled plasma optical emission spectrometry (ICP-OES), the resistance furnace with infrared detector (RF-IF) and the atomic absorption spectrometry (AAS). Based on the results of this analysis, main elements and potentionally hazardous elements of phosphors subgroup were defined. Concentration of rare...
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Element analysis of magnesium alloys using laser induced breakdown spectrometry
Veis, Samuel ; Fintová, Stanislava (referee) ; Doležal, Pavel (advisor)
Bachelor‘s thesis is aimed at assessing the possibilities of trace elements detection in magnesium alloys using laser induced breakdown spectroscopy with a focus on rare earth elements. Base materials were wrought magnesium alloy sheet ZE10 with thickness of 1,6 mm and ZE41 with thickness of 2 mm produced using Direct Chill casting method. Qualitative and quantitative ways of LIBS spectra evaluation were described in the work. Qualitative analysis confirmed the presence of La, Ce, Nd and Pr in ZE41, and La with Ce in ZE10. These informations confirm results of EDS analysis. For a demonstration, quantitative analysis of ZE10 was made, which confirmed the possibility of using LIBS for detection of REE in Mg alloys.
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