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Speciation and isotopic composition of lead in coal samples from selected profile of the Most Basin
Semíková, Hana ; Strnad, Ladislav (advisor) ; Chrastný, Vladislav (referee)
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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Use of trace elements and Pb isotopes for bioarchaeological research of selected burial grounds
Bartoš, Jan ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee)
SUMMARY: Aim of this thesis is to provide, by using trace elements analysis and Pb isotopes analysis of archaeological findings from Roman era and following migration period, informations about basic bioarchaeological parameters of sites Abrahám, Rusovce II and Sládkovičovo (territory of present Slovakia) and Sopianae site (area of present Pécs city in Hugary). Analyses were performed on samples of 81 bones and 21 dental enamels. For purposes of this work most important concentrations are of Ca, P, Sr, Zn, Ba, Fe, Al, Mn and Pb (and its isotopes). They were consequently used for calculating Ca/P ratio in order to assess extent of after-burial diagenetic changes. For this purpose Al and Fe concentrations were taken into account too. Sr/Ca and Sr/Zn ratios were compared to assess prevailing type of diet. The Ba/Ca and Sr/Ca ratios were compared in order to asess supposable mobility of some individuals. By using of Pb concentrations and its isotopes contamination by this metal was assessed. During interpretations of individual conclusions useability of samples outgoing from assessment of extent of diagenetic alterations were always taken into account. Little changes in chemical composition of samples arise in case of Sopianae site, samples from other sites are greatly preserved. Using of paleodietary...
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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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Lead isotopic composition of selected certified reference materials in three step extraction procedure.
Martinovský, Václav ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee)
This work deals with the issue of lead isotopic composition in reference materials. These reference materials were extracted by using method of sequential extraction analyses Isotopic composition of the lead was determined by ICP MS (Thermo scientific). The first part summarizes knowledge in the field of sequential extraction analyses; in the following section issue of using isotopic composition of lead in environmental sciences is discussed. Experimental part describes research methodology and presents results of the sequential extraction and the isotopic composition of lead contained in the analysed reference materials. Following reference materials were analysed: CRM BCR 483, CRM BCR 701, SRM NIST 2709a, SRM NIST 2710a, SRM NIST 2711a. Results of modified sequential extraction procedure BCR (three steps methodology created by Community Bureau of Reference, Belgium to harmonize technical procedure) measured in this work corresponds to the certified or indicative values. Isotopic composition expressed by isotopic ratios 206 Pb/207 Pb among fractions of BCR sequential extraction (fractions I - IV) was folloving: CRM BCR 483 (1,1168 - 1,1350); CRM BCR 701 (1,1583 - 1,1844); SRM NIST 2709a (1,1819 - 1,2118); SRM NIST 2710a (1,1583 - 1,1989); SRM NIST 2711a (1,1079 - 1,1284). Key words: lead isotopic...
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Exogenic alteration of geomaterials with anomalous content of hazardous elements
Udatný, Martin ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee) ; Vaněk, Aleš (referee)
of dissertation thesis Exogenic alteration of geomaterials with anomalous content of hazardous elements The research of waste materials from high temperature processes belongs to current issues solved in the field of modern environmental geochemistry. Current research has mainly been focused on fly ash and bottom ash coming from metallurgy, combustion and other industrial processes. In these wastes of different grain size, accumulation of hazardous elements occurs. These elements may be present in low concentrations in combusted coal or municipal solid waste or it may come from ore processing. Hazardous compounds are also intentionally added during the technological process (e.g. making of lead glass). Modern industrial plants are equipped with effective filtration systems, but this might not be in the past. In the Czech Republic and elsewhere in the world old environmental burdens are and will be addressed. Current modern filtration systems are never 100% efficient. Contamination of surrounding environment in a lesser extent can still occur. The production of lead glass (Bohemian Crystal) is based on the addition of lead compounds in the glass raw material. Additions of these substances providing a high refractive index of the finished product. Also compounds containing other hazardous elements...
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Mineralogy and genesis of gold ores hosted by porphyry dykes at Petrov and Bohuliby
Petrov, Ivan ; Zachariáš, Jiří (advisor) ; Strnad, Ladislav (referee)
This bachelor thesis is focused on mineralogy and genesis of Au-bearing ores in southwestern part of the Jílové ore district, in between Petrov and Bohuliby. Crystallization sequence of hydrothermal minerals was identified by textural relationships of mineral phases. Arsenopyrite and chlorite thermometry suggest formation of sulphides and gold at 400-300 řC. Within the scope of this thesis the paragenesis of rock-forming minerals of granodiorite porphyry dikes hosting Au-bearing ores, as well as of late-magmatic to hydrothermal minerals filling in miarolitic cavities in these porphyries, were also interpreted. A hypothesis of granodiorite dikes' origin is suggested as well, involving mixing of magmas with different geochemical signatures.
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Vnímání pojmu občanství budoucími učiteli oboru Výchova k občanství
STRNAD, Ladislav
The thesis is focused on the perception of the concept of citizenship by future teachers in the field of Education to Citizenship. It consists of two parts, theoretical and research. The theoretical part deals with the development of citizenship in the territory of the Czech Republic in connection with the historical development of our republic from 1918 until present. It also looks at the questions of when and how nationalism originated, its currents and how it manifested itself in the past of our state. The research part based on a quantitative survey maps students' awareness of the institute of citizenship, their orientation in the history of our citizenship, opinions on causes, negatives and positives of nationalism, and it points out their attitudes to the nationalities that lived in our territory.
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