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Variation of Pb-isotopic composition in coal basins
Čurda, Michal ; Strnad, Ladislav (advisor) ; Mihaljevič, Martin (referee)
This Bachelor Thesis is devided into three main parts. The first part has a character of a research and describes the presence of lead in coal, in deposits of ore, in peat bogs, or in lake and flood sediments. The second part briefly describes the analythic methods used to determine lead in natural material. The third - practical part is focused on measurement of samples taken from the sokolov brown coal basin. It describes the laboratory method of the preparation of the samples for the analysis of contents and isotope composition of lead using ICP - QMS.
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Lead isotopic ratio determination in soils
Kotrč, Vlastislav ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee)
This barchelor thesis deals with the issue of lead in the environment, with its main focus being on describing the right analytical method for determining the isotopic composition of lead in soil. First part this thesis summarizes the most important characteristics and properties of lead. Next part is concerned with the methodology of collection and preparation of soil samples for the analysis itself. The thesis then contains detailed description of the analytical method, which is being currently the most used for determining the isotopic composition of soil - mass spectrometry with inductively coupled plasma. Since this is not a research thesis, in the fifth part, results of studies from the Příbram region are presented, alongside other possible uses of this method. Key words: lead isotopic composition, soils
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Biogeochemical cycle of rare earth elements in the Lesní potok catchment
Dubroková, Jitka ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee) ; Chrastný, Vladislav (referee)
110 Summary The study of biogeochemical cycle of rare earth elements (REE) carried out in the Lesní potok catchment and its vicinity (located in the Nature State Reserve, Voděradské bučiny, 30 km SE of Prague) was focused on the monitoring of REE concentrations and distribution patterns in natural environment, their relationship with other analysed elements and compounds such as Al, Ca, Fe, K, Mg, Mn, Na, P, S, Si, F- , Cl- , NO3 - SO4 2- , HCO3 - and organic carbon, and its response to physicochemical conditions in various investigated ecosystem compartments. The samples of soil, stream sediment, stream and ground water, rainwater and throughfall in beech and spruce forest, samples of tree assimilatory organs, bark and stem wood of Norway spruce (Picea abies) and European beech (Fagus sylvatica) and lichens (Hypogymnia physodes) were collected in the catchment and its vicinity. Liquid samples were acidified with dilute nitric acid to prevent losses by adsorption, and filtered using a 0.45 µm membrane filter. Stream water samples sampled in months characterized by low and high discharge were processed by ion exchange chromatography and membrane dialyses. Solid samples were dried to constant weight (and sieved and homogenized in case of soil stream sediment samples) and decomposed in the microwave oven with...
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Distribution of trace elements in tectites with using LA ICP-MS
Svatá, Adéla ; Strnad, Ladislav (advisor) ; Houzar, Stanislav (referee)
The following example deals with methods of determining major and trace elements in a particular special kind of natural glasses - tektites. Measurements were performed on seventeen samples. Two of them belonged to a group of Libyan desert glass and the remaining fifteen were originally from the Australasian tektite field. For these purposes, optical microscopy was used in the preparatory phase of study of the samples. The studied samples were prepared in the form of cross-sections. Microscopy was employed to ensure the correctness of the procedure for selecting appropriate samples and precise areas of cross-sections that are suitable for analysis. The main elements were determined by electron microanalysis. The values obtained in these measurements confirmed existing knowledge about the composition of tektites. The chemistry of Libyan desert glass corresponded to 98 weight percent of SiO2. In the Australian-Asian samples, this value was equal to 73 wt.%. The other major oxides include Al2O3, FeO, MgO, etc. The contents of these elements in the Libyan desert glass were determined in the range of 0.154 to 0.727 percent by weight. The Australasian tektites contained 0.598 to 0.875 wt.% of these elements. The most important data were obtained by inductively coupled plasma mass spectrometric (ICP-MS)...
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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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Problematic of behaviour of APC residues from metallurgical recycling of Pb in soil environment
Vrtišková, Růžena ; Strnad, Ladislav (referee)
Fly ashes from the metallurgical processing of Pb represent the main pollution source of soils in the vicinity of the smelters. The purpose of this thesis was to determine the leaching behaviour of the metallurgical fly ash in simulators of soil solutions - low-molecular-weight (LMW) organic acids. Batch leaching experiment was performed in the time span of 168 hours, at the solid-to-liquid ratio of 1/10 and in 500 µM solutions of organic acids (acetate, oxalate and citrate). In the leachate of acetate and oxalate were measured high concetration of heavy metals as Pb, Cd and Zn. Whereas the leaching efficiency of citrate was lower due to higher pH of suspensions, which is the main factor in this leaching process. According to the calculations using the PHREEQC-2 program the amount of Pb and Cd organic complexes in the leachate are minor (0,1 - 2,1%). Suprasing is the amount of organics complex of Zn and Cu (ZnCitrate- , CuCitrate- ), which is expected to be less mobile due to sorption onto positively charged surface of hydrous ferric oxides and organic matter. As far as acetate and oxalate are concerned, Pb concentrations at the end of experiment are controlled by precipitation of solid Pb acetate and oxalate. This phenomenon can represent a key mechanism of Pb immobilisation in soil systems, in...
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