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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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Restriction on Mercury in Measuring Devices according to the REACH
Šejblová, Barbora ; Bendl, Jiří (advisor) ; Mihaljevič, Martin (referee)
REACH - is the European Community Regulation on chemicals and their safe use (EC 1907/2006). It deals with the Registration, Evaluation, Authorisation and Restriction of Chemical substances. The law entered into force on 1 June 2007. The aim of REACH is to improve the protection of human health and the environment through the better and earlier identification of the intrinsic properties of chemical substances. At the same time, REACH aims to enhance innovation and competitiveness of the EU chemicals industry. The REACH Regulation places greater responsibility on industry to manage the risks from chemicals and to provide safety information on the substances. As a central point in the REACH system has the European Chemicals Agency (ECHA) based in Helsinki, which manages the data required for operation of the system. The aim of this paper is to introduce the proposed restrictions (June 15th , 2010), which refers to the use of mercury in measuring devices, and how it is prepared by the European chemicals policy and directives - REACH. Furthermore, this work describes a reliable safe and technically and economically feasible alternatives for measuring devices containing mercury. The introduction of restrictions can reduce the amount of mercury in the EU market in the measuring equipment by about 57 tons...
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Speciation Analysis of Mercury concentrated on Selective and Sequential Extraction
Martinovský, Václav ; Mihaljevič, Martin (advisor) ; Holý, Martin (referee)
This bachelor thesis deals with methods of speciation analysis of mercury concentrated to selective and sequential extraction of mercury. The first part contains the basic information about characteristics, sources of pollution, toxicity and cycle of mercury in environment. The following part defined term of speciation and speciation analysis. Next chapters are concentrated to description and characterization appropriate and often used extraction reagents and procedures and schemes of selective and sequential extraction methods of speciation analysis. Specific procedures of SEA are described in this thesis and mentioned are their major advantages nad purphose. The last chapter is devoted to listing methods of instrumentation useful to determination of extractable forms of mercury.
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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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Determination of mercury content in materials in various stages of wine production, geochemistry of mercury in the vineyard
Buchtová, Jana ; Mihaljevič, Martin (advisor) ; Száková, Jiřina (referee)
This work was focused on determination of mobility of mercury and its content in materials from each part of the wine production process. The aim of this work was to establish the most suitable analytical method for determination and evaluation of changes in content of mercury during the production process. Samples of soil, biomass, vine wood, vine leaves, berries, grapes, rough wine and cider sediment of red wine and also four liquid samples of white wine were analyzed. All the samples originated from the area of Malé Žernoseky and Rudoltice nad Bílinou, white wine samples were collected in Chrámce u Mostu in the northern part of the Czech Republic. Analyzer AMA 254 was used for determination of mercury in solid samples and liquid samples had to be prearranged by PSA analyzer. This analytical approach was not so sufficient and mercury from liquid samples had to be captured by gold-coated amalgamator in first step and then analyzed by AMA 254. Obtained results confirmed interception of mercury mostly in leaves and in the grapes peelings. The grapes from Rudoltice contained 0,0022 mg/kg in dry mass and further processed wine grapes contained 0,0068 mg/kg in dry mass. The lowest content of mercury was in cider and completed wine contained less mercury then the rough wine. Unfiltrated cider from Chrámce has...
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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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Weathering of arsenopyrite in soils in acidified environment
Soukupová, Lenka ; Drahota, Petr (referee) ; Mihaljevič, Martin (advisor)
Lenka Soukupová, Zvětrávání arsenopyritu v lesních půdách v acidifikovaném prostředí SUMMARY The weathering of arsenopyrite (FeAsS) has been studied at the experimental site Načetín in the Ore Mountains, Czech Republic. There were chosen three areas with different vegetation (beech, spruce a unforested areas) at this site. The arsenopyrite samples were placed in all soil horizons (litter, horizons A, B and C for forest areas; horizons A, B and C for unforested area), where they were exposed to ambient conditions for one year. After one-year weathering, the newly formed secondary minerals were identified and the rate of surface oxidation was determined, both depending on the environment of oxidation. Although physical-chemical parameters and content of main and trace elements of the studied soils varied, the only detected crystalline secondary mineral of arsenic was scorodite (FeAsO4∙2H2O). Nevertheless, this differences affected amount of formed scorodite. The highest concentrations were determined on the surface of the arsenopyrite grains that oxidized in the beech stand, conversely the lowest concentrations were determined on the arsenopyrite grains from the unforested area.
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