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Elemental analysis of the flat display devices for urban mining
Štípek, Radek ; Strnad, Ladislav (advisor) ; Mihaljevič, Martin (referee)
aaaaaRare earth elements (Sc, Y and group 15 lanthanides) and their compounds currently have significant practical use in metallurgy, glass industry, as highly active catalysts for the production of so-called. NiMH batteries, alloys for the manufacture of permanent magnets and e.g. moderators rods in the nuclear energy, but above all they have an irreplaceable role in modern electronics for phosphors TV screens, CRT earlier today, PDP and LCD monitors and displays, tablets, mobile phones etc., which give them a high-quality picture and sound. Unlike most base and precious metals are concentrated in the conquerable ore deposits, occur in the form of compounds as part of mixed minerals in the rarely economically exploitable concentrations, a mining and processing is costly and negative impacts on the environment, paradoxically towards the title but their overall content in the crust is relatively high, the average concentration in the range of about 150 to 220 ppm. The main world producer of REE, China, in 2010, significantly reduced exports by 40 %, making prices of some REE increased up to 1500 % during the month. Demand for REE is growing, so often talks about the recycling of valuable materials back into production, as called. "Urban mining", ie "urban mining", thereby reducing the amount of...
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Application of the laser ablation ICP-MS in the analysis of gem opals
Čimová, Nikoleta ; Strnad, Ladislav (advisor) ; Zachariáš, Jiří (referee)
15 samples of gem opals were analyzed by laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) and inductively coupled plasma mass spectrometry (ICP-MS). For this study were selected the most representative samples from Slovakia, Australia, Peru, Ethiopia, Mexico, USA and the Czech Republic. These samples were obtained from private collections. The study focuses on the geochemical relationships between various forms of opal originating from igneous and sedimentary environments based on the results from LA ICP-MS and ICP-MS. The major and trace element compositions are unique for each studied opal locality and important for understanding numerous aspects of opal formation. Major element analysis shows that opals are essentially pure SiO2 (77 - 92 wt. %). Al, Fe, Ca, K, Na and Mg are the main elemental impurities. The concentrations of the trace elements vary strongly depending on the opal locality. Differences were found, e.g., in the concentrations of REE and some refractory elements, which might be indicative for determining the provenance of opals. Many studies have been published explaining the origin of luminescence, microstructures and the thermal properties of opals. However, there are very few comprehensive studies comparing gem opals from the most important historical and...
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Spectrometric determination of selected metals in the samples from old ecological burden area
Zurynková, Pavla ; Kratzer, Jan (advisor) ; Spěváčková, Věra (referee)
This bachelor thesis is focused on heavy metals pollution in the Králíky town and its vicinity, located in the Pardubice region. This region was selected because there had been a Tesla factory producing fluorescent lamps. Moreover, there is also a waste disposal of the fluorescent lamps wasters and other dangerous waste located about two kilometers far from the former factory. Soil samples from the waste disposal area as well as river sediment, samples taken in the Tichá Orlice river and the Králický brook have been analyzed Mercury, cadmium, lead, chromium, nickel, copper and arsenic levels in the samples were measured by inductively coupled plasma - mass spectrometry. The total mercury content has also been measured with single-purpose atomic absorption spectrometer AMA-254. An optimization of leaching conditions of the elements was performed prior the analysis of the samples employing certified reference material. High levels of mercury, cadmium, lead, chromium, nickel and copper have been found in the waste disposal area. Regarding the sediment samples the highest levels of pollution have been detected near outfall of the sewage water from the industrial area in the Králíky town (former Tesla factory and recent metal plating industry). The concentration of heavy metals in other sediment...
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Determination of Pt metals in environmental samples
Kotková, Kristýna ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee)
Platinum group elements are increasingly used in various industries, and that generates their occurrence in many parts of the environment, including biota. The interest of scientists is currently focused on studying the behavior of Pt metals in the ecosystem because of the potential health risks of Pt metal compounds. There are used various techniques for this purpose, including analytical methods. This bachelor thesis deals with properties of PGE, their appearance and behavior in the environment. The aim of the bachelor thesis is to review the analytical methods used to determine the Pt metals in environmental samples. Key words: platinum group elements, determination, ICP-MS
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Speciation analysis of toxicologocally important forms of arsenic: development and comparison of hydride generation based methods with ICP-MS detection
Trojánková, Nikola ; Matoušek, Tomáš (advisor) ; Száková, Jiřina (referee)
Nowadays, arsenic is becoming an important pollutant in the environment. Chronic exposure to arsenic can cause number of serious diseases. Therefore, a development of analytical methods for trace and ultratrace speciation analysis- analysis of individual forms or phases in which As is found in the sample - is fully in place. This Thesis compares four methods of trace speciation analysis, with focus on limits of detection and quantification, and on comparison of results of analysis of river and sea water reference materials. Methods based on hydride generation with preconcentration by cryotrapping and AAS or ICP-MS detection, with limits of detection in ng or tenths of ng·dm-3 , are compared with procedures employing HPLC, with ICP-MS detection. The Thesis includes development and optimization of a pre-reduction step of postcolumn hydride generation with on-line pre-reduction of pentavalent arsenic species, in order to improve sensitivity of this method. Limits of detection around 10 ng·dm-3 are achieved. The results of analyses obtained by individual methods are in excellent agreement. Keywords: Arsenic, speciation analysis, hydride generation, atomic absorption spectrometry, inductively coupled plasma- mass spectrometry, high efficiency liquid chromatography, limits of detection.
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Speciation and isotopic composition of lead in coal samples from selected profile of the Most Basin
Semíková, Hana ; Chrastný, Vladislav (referee) ; Strnad, Ladislav (advisor)
Coal is one of the major energy sources in the world and contains most of the elements from the periodic table. During combustion of coal these elements are released and redistributed. This may lead to environmental problems. Some of these elements are considered to be very dangerous for human and animal health and ecosystems. The knowledge of concentration and speciation of elements in coal is important for the prevention of the adverse environmental phenomena associated with the use of coal. One of the hazardous elements in coal is lead. The purpose of this work is to determine the concentration of lead and its isotopic composition simultaneously with determining the speciation of lead in coal. The ICP-MS method was used to determine the concentration and isotope ratios of lead. A total of 62 samples of subbituminous coal was analyzed. The method of selective extraction analysis BCR was used on 9 samples of subbitumnious coal to identify the speciation of lead in coal. Lead concentrations in coal were measured in the range of 0.25 to 78.84 mg·kg-1 . These concentrations correspond to the average concentrations of lead in most of the coals. Isotope ratio 206 Pb/207 Pb in coal samples ranged from 1.169 to 1.219. Isotopic 208 Pb/206 Pb ratio was measured in the interval 2.047 to 2.093. The isotopic...
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Properties of Aerosol, Produced by Laser Ablation of Standard Materials for ICP-MS Analysis.
Holá, M. ; Nováková, H. ; Ondráček, Jakub ; Vojtíšek, M. ; Kanický, V.
Laser ablation (LA), together with inductively coupled plasma mass spectrometry (ICP-MS) as a detection system, has become a routine method for the direct analysis of various solid samples. The product of laser ablation contains a mixture of vapour, droplets and solid particles. All components are finally transported to a plasma by a carrier gas as a dry aerosol including mainly agglomerates of primary nanoparticles. In general, characterisation of aerosols by their particle size distribution (PSD) represents indispensable tool for fundamental studies of the interaction of laser radiation with various materials. The particle size distribution of dry aerosol originating from laser ablation of standard material was monitored by two aerosol spectrometers – Fast Mobility Particle Sizer (EEPS) and Scanning Mobility Particle Sizer (SMPS) simultaneously with laser ablation - ICP-MS analysis.\n
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22016102412241 - PDF
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Platinum group elements in waste and surface waters
Novotný, Matěj ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This assignment provides a detailed description of platinum metals, their occurrence in surface and waste water and their determination options. Currently, platinum metals are widely used in the automotive industry as a part of a catalyst, as well as in medicine and jewelery. Release of these metals in pure form and the form of oxides leads to their subsequent accumulation, which directly affects fauna and flora. Due to that, the living conditions and health status of some organisms are petting worse.
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