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Dating of uranium secondary minerals by the Thermal ionization mass spectrometry and α-spectroscopy
Roll, Michal ; Goliáš, Viktor (advisor) ; Strnad, Ladislav (referee)
SUMMARY: This paper is focused on analytical methods, specifically on thermal ionization mass spectrometry and alpha spectrometry; both methods are often use for dating of minerals or rocks. Goal of this paper is to compare these methods and decide which one is more suitable for dating of secondary uranium minerals. Methods are completely different and we judge them closely and take into account every fact not just technical skills as accuracy or speed which are in favor of thermal ionization mass spectrometry, but also device availability, price or published researches which are in favor of alpha spectrometry. There is also suggestion that both methods can cooperate and it seems as most effective way and there is another suggestion how studies a secondary uranium minerals.
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Rare earth elements in electronic waste
Pospíšilová, Eliška ; Šebek, Ondřej (advisor) ; Strnad, Ladislav (referee)
Rare earth elements consist of 15 lanthanides, Y and Sc. They are currently very important materials in many industrial branches (metalurgy, pollishing). One of these options is the usage as the compound of phosphors in electronic devices (television and computer displays. Because of their manufacturing cost, options of recovery from waste electrical and electronic equipment (WEEE) are investigated. This thesis deals with compoud elements of phosphors from displays of type CRT (cathode ray tube) and plasma TV. The 37 samples of phosphors from different displays were taken and processed for study of the compoud elements. Phosphors were separated to 4 subgroups in accordance with the corresponding type of displays: black-and-white CRT television displays (CRT_CB), color CRT television displays (TV_B), color PC displays (PC_B) and monochromatic PC displays (PC_M). The study was carry out by multiple features analysis that combined the inductively coupled plasma mass spectrometry (ICP-MS), the inductively coupled plasma optical emission spectrometry (ICP-OES), the resistance furnace with infrared detector (RF-IF) and the atomic absorption spectrometry (AAS). Based on the results of this analysis, main elements and potentionally hazardous elements of phosphors subgroup were defined. Concentration of rare...
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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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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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The 234U/238U isotope ratio in waters near the uranium mineral deposits
Fanta, Martin ; Goliáš, Viktor (advisor) ; Strnad, Ladislav (referee)
Uranium has three natural isotopes: 238 U, 235 U and 234 U. Isotopes 238 U and 235 U are primordial, isotope 234 U is one of the daughter products of 238 U decay series. Genetically dependent uranium isotopes 238 and 234 are fractionated in nature. The main reason is the alpha recoil in solid (crystalline) phase, where there is a preferential settling subsidiary 234 U in a higher oxidation state (VI). The isotope 234 U is then more available at the recent geochemical processes: leaching and alteration. Water then usually has 234 U/238 U activity ratio higher than 1, while the activity ratio in solid residuum is smaller than unity. Isotopic ratio in water is dependent on many factors. The most important are the nature of source rocks, weathering rate, the dynamics of geochemical processes (e.g. fluid-flow velocity) or anthropogenic influence on geological environment at mining of uranium deposits. Identification of these fractionation factors is not easy. Differences in the isotope ratios in water may be used to identify the source of uranium and to evaluate the contribution of technogenic uranium.
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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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Vlivy působící na hmotnost jehňat ve 100 dnech u plemene texel
STRNAD, Ladislav
The aim of this diploma thesis is to evaluate the chosen influences which effects the weight of lambs in the age of 100 days of breed texel. The evalution was done from 2013 to 2016 and the basic data set is consisted of 1149 lambs. The observed effects were sex, litter size, month of birth, year of birth, mother's age, father's line, and mother's father line. There was found a statistically highly significant difference in the monitoring of sex influence in male lambs (34,69 kg). A statistically significant difference was found in singles (35,14 kg) when evaluating the influence of litter size. There was found a statistically significant differences between the lambs born in May (36,78 kg) and February (37,29 kg), according to the influence of the month of birth. There is also the influence of the year of birth, a statistically highly significant difference was found between 2016 and 2015. There wasn't found a statistically significant difference in the influence of the mother's age. The influence of the father's line proved a statistically highly significant differences in the TAXI line (36,81 kg) and TAYLOR (37,76 kg). The evaluating of the influence of the mother's father line didn´t show a statistically significant difference in the TRISK line (48,50 kg). There wasn´t found a statistically significant difference in interaction of mother's father line and litter size.
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Trace elements and Pb isotopes in selected bone samples
Bartoš, Jan ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee)
The aim of this work is briefly summarize the current theoretical knowledge about trace elements and their inputs into calcified body tissues in a form of search. Here are described mechanisms of their inputs and depositing into human body and principles, which allows maintenance of their optimal levels. In this paper are also described the properties of bones and teeth and simply explained concepts such as an essential and toxic trace elements. The next part of this work is mainly about trace elements, which have the biggest potential to be used in an archeological research, particularly in paleodietary research. These elements are mainly Sr, Ba and Zn. Lead and its isotopes are discussed more here in relation to the effect of Pb to Romans in the past and to the identifying sources of pollution by this element. In the same chapter are also described principles of post-mortem alteration processes, to which are bones after burial exposed and which they have to face during analyzing and interpretations of data related to the amount of trace elements in origin bones.
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Tree rings as a Pb pollution archive
Šimeček, Martin ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee)
The Bachelor's thesis is written as a research talking about storing Pb in tree rings. The first part speaks about the basic characteristic of the pollutant, his natural and anthropogenic deposits. Following chapters are comparing the tree rings with the peat bogs, which are often used as a natural archive of the contamination by the metallic elements. Than I continue with the description of the transport of Pb into wood and subsequent radial distribution in tree rings. One of the chapters concludes the results of certain researches of tree rings. The main time sections of environmental pollution in the 20th century are shown by the results of researches on the concentrations and isotope ratios of Pb. These studies informe us also about sources causing this pollution. The thesis includes also a chapter about bark pockets, which can be used as another alternative to observe the movement of Pb in the environment. The last part describes the method ICP-MS usually used to determine Pb in natural materials.
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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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