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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 selected elements in plant extracts by atomic absorption spectrometry
Rydlová, Lenka ; Hraníček, Jakub (advisor) ; Kratzer, Jan (referee)
The aim of this bachelor thesis was to determine selected elements (Na, Mg, K, Ca, Zn, Se) in plant extracts and juices by atomic absorption spectrometry using different types of atomization. Each method has been optimized for determination of the mentioned elements. For flame atomization it has been used optimization of height of the primary radiation from the hollow cathode lamp over the edge of the burner. The height was generally between 6.0 and 8.0 mm. Then there have been optimized flow of each component of the flame (acetylene, air, nitrous oxide) and it has been set location of the hollow cathode lamp and the flame. Under the optimized conditions basic characteristics describing the method of the determination of mentioned elements have been measured (LOD for sodium 2.13 µg L-1 , for magnesium 2.44 µg L-1 , for potassium 11.3 µg L-1 , for calcium 15.6 µg L-1 , for zinc 6.04 µg L-1 , for selenium 0.34 µg L-1 ). In the next part of the thesis the optimized methods have been used for measuring concentration of all elements in real samples. After the preparation of the samples including dilution, addition of various reagents etc., they have been atomized by flame in an atomic absorption spectrometer (Na, Mg, K, Ca, Zn) and determined, or converted to a volatile compound (Se) and determined by...
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Extraction of Selected Mercury Compounds from Real Samples for Speciation Analysis Employing RP-HPLC-UV-CVG-QTAAS
Kolorosová, Alžběta ; Červený, Václav (advisor) ; Kratzer, Jan (referee)
The extraction of mercury species (methylmercury, ethylmercury, phenylmercury and inorganic mercury(II)) from fish tissue, its determination by reverse phase HPLC, UV-photochemical generation of cold vapour, and detection by atomic absorption spectrometry is described in this work. Various extraction agents and digestion methods were compared in order to find the best alternative. The mixture of 6.25% tetramethylammonium hydroxide and 0.05 mol·l-1 hydrochloride acid was chosen as the best extraction agent. In addition to the high extraction efficiency, the solution involved positively not only UV-photochemical generation, but also separation of observed species. On the contrary, the poor repeatability was achieved with the microwave-assisted digestion due to the proved sorption of mercury species on the Teflon vessels. Therefore, the extraction by high temperature (50-60 řC) in glass bottles was preferred. The results of the determination of the mercury species after the extraction from the real samples were compared to the outcomes obtained by AMA 254. The proposed extraction technique together with the RP-HPLC-UV-CVG-QTAAS is suitable for the speciation analysis of mercury.
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Modular design for in-atomizer preconcentration of hydride forming elements with AAS detection
Novák, Petr ; Kratzer, Jan (advisor) ; Korunová, Vlasta (referee)
Modular design of hydride trap-and-atomizer device for AAS is constructed and tested. Modular design enables to test different preconcentration surfaces easily. Efficient in- atomizer preconcentration allows to reach detection limits of hydride forming elements at ultratrace levels. Bismuth and arsenic were chosen as model analytes and their preconcentration efficiencies were quantified employing quartz and sapphire as preconcentration surfaces. The results reached in the modular design were compared to those found previously in the compact quartz trap-and-atomizer device. The performance of the modular design is fully comparable with that of compact trap-and-atomizer design. Modular design can thus be employed for testing of novel preconcentration surfaces.
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Interference study by selenium determination using UV-photochemical generation of its volatile species in formic acid media with AAS detection
Duben, Ondřej ; Červený, Václav (advisor) ; Kratzer, Jan (referee)
The aim of this work was to experimentally observe the impact of various potential interferents on the determination of selenium using UV-photochemical generation of its volatile species in formic acid media with AAS detection. HNO3, As3+ , Co2+ , Cu2+ and Ni2+ were chosen as model substances affecting the analyte response. All these substances were found significant interferents. Some of these substances (HNO3, As3+ , Cu2+ , Ni2+ ) increased the signal at low concentration, but the signal of selenium decreased significantly at their higher concetration in a sample. Inverse shape of the dependence of the analyte response on the interferent concentration was observed for Co2+ ions. It was found that the reagent Chelaton II, often used in analytical chemistry to mask interferents, also caused a suppression of selenium signal. On the contrary, other maskig agents tested (triethanolamine, amonnium formate) did not lead to any interference. Key words: selenium, UV- photochemical generation of volatile compounds, formic acid, AAS, interference, masking
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Preconcentration of Hydride Forming Elements in Quartz Atomizers for Atomic Absorption Spectrometry
Kratzer, Jan ; Dědina, Jiří (advisor) ; Komárek, Josef (referee) ; Spěváčková, Věra (referee)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF SCIENCE Department of Analytical Chemistry PRECONCENTRATION OF HYDRIDE FORMING ELEMENTS IN QUARTZ ATOMIZERS FOR ATOMIC ABSORPTION SPECTROMETRY Synopsis of the PhD Thesis Prague 2008 RNDr. Jan Kratzer 2 CONTENTS CONTENTS................................................................................................................... 2 CURRICULUM VITAE............................................................................................... 4 LIST OF PUBLICATIONS ......................................................................................... 6 ABSTRACT................................................................................................................... 9 1 ULTRATRACE ANALYSIS OF HYDRIDE FORMING ELEMENTS ....... 11 2 OBJECTIVES OF THE THESIS ...................................................................... 13 3 EXPERIMENTAL .............................................................................................. 15 3.1 Apparatus ....................................................................................................... 15 3.2 Procedure........................................................................................................ 16 3.3 Detection by atomic absorption spectrometry...
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