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Quantification of main solution components by using fragments containing heavy nuclides of common elements
Horká, Blanka ; Čabala, Radomír (advisor) ; Bajer, Tomáš (referee)
Quantification of major components by gas chromatography with flame-ionization detector (GC-FID) is established in routine laboratory practice. The FID detector is considered as universal detector for gas chromatography (GC), but it does not provide a response for a wide range of compounds and GC-FID analysis provides only quantitative data. The coupling of gas chromatography with mass spectrometry is a powerful analytical tool that provides not only quantitative data but also qualitative data on the structure of substances. When quantified by GC-MS, the detector oversaturation is a problem as it is a highly sensitive detector (at ppb level). One way to avoid oversaturation of the detector is to significantly dilute the solutions, which causes a decrease in the sensitivity of the method. Another approach to bypass detector saturation is to interrupt detection during solvent elution. For quantification of the major components of solutions, only the first method of bypassing detector saturation can be applied, but it is a labor-intensive process that increases the measurement uncertainty. The interruption of detection during solvent elution is not applicable for the purpose of quantifying major components, so a new approach of quantifying major components of solutions using M+1 ions was proposed and...
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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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Tree rings dendrochemistry near Cu smelter
Jarošíková, Alice ; Mihaljevič, Martin (advisor) ; Hojdová, Marie (referee)
Nkana smelter belonged to the main sources of contamination by trace elements (especially Cu and Co) in the area of African city Kitwe (Copperbelt, Zambia). The main objective of this study was to compare elemental and isotopic composition of Zambian soils and tree rings, and to investigate biogeochemical processes between plants and soils in contaminated and uncontaminated environment. Elemental composition (Cu, Co, Cr, Mn, Fe, Zn, Pb, Cd, Hg and Tl) and isotopic composition of Cu (63 Cu/65 Cu) were determined in soils and tree rings of pine trees (Pinus latteri, Pinus kesiya) using ICP-MS , AMA and MC ICP-MS. Our results demonstrated that soils and tree rings were both affected by mining and metallurgical activity. Increasing content of elements with depth is the result of the mobility of the elements in uncontaminated soil profile. Soil from contaminated site had the highest metal contents especially in the upper part of the soil profile as a result of continuous contribution of metallurgical components during long-term smelter operation. Fractionations of Cu isotopes in soils were caused primarily by interactions with plants. Concentration changes that some elements showed in the individual tree rings could be the effect of variable intensity of pollution in the area. In the case of Cu, however,...
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Freshwater wetlands as a biogeochemical archive: Temporal changes in climate and environmental records
Zemanová, Leona ; Novák, Martin (advisor) ; Mihaljevič, Martin (referee) ; Hojdová, Marie (referee)
Worldwide, peatlands cover an area of 4.106 km2 . Plant primary production dominated over organic matter decomposition and enabled organic matter to accumulate during the last 11 000 years. Peatlands represent a reservoir of atmospheric carbon and they are a useful scientific tool for reconstructions of historical atmospheric pollution. The first part of the thesis focuses on peatlands as a dynamic carbon reservoir under predicted climate change that would influence carbon cycling and emissions of greenhouse gases into the atmosphere. Three methodological approaches were used - a mesocosm laboratory incubation, a transplant experiment and in situ gas flux measurements. The laboratory incubation studied the response of peat samples from temperate (Velké Dářko, Czech Republic) and boreal (Stor Åmyran, Sweden) zone to a temperature increase, water table decrease and their combination. Today, the warmer site exhibits ~14 times higher CH4 production potential than the colder site (28 mg m-2 hr-1 at VD, and 2 mg m-2 hr-1 at SA). Both sites respond differently to temperature increases. Changes in methane production were up to 9 fold due to different temperatures. A gradual decrease of water table level from 2 to 14 cm below the peat surface had a much stronger effect, VD exhibited a decrease in methane...
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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 stable isotopes in hair for understanding nutrition and population migration
Tomášková, Anežka ; Brůžek, Jaroslav (advisor) ; Kovačiková, Lenka (referee)
The analysis of stable isotopes of teeth and bones shines a new light on bioarcheology, understanding of nutrition as well as mobility of mankind in past. However studying stable isotopes which can be found in animal or human hair (carbon - δ13 C, nitrogen - δ15 N, oxygen - δ18 O and probably more) provide information of the same quality. This kind of information is not enriching only to bioarcheology, but also to other fields connected to antropology such as forensic science or medicine. This paper delivers basic overview of principles of determinig the content of stable isotopes in biological material and show advantages and disadvantages of using hair. Information which are used for further understanding of nutrition, mobility and geo-origins are demonstrated on examples from bioarcheology, forensic and clinical medicine.
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Soil archives of chernozems
Kolařík, Petr ; Strouhalová, Barbora (advisor) ; Trubač, Jakub (referee)
Soil archives provide valuable information on the past of the environment, in particular vegetation history (Costantini 2018). The aim of this thesis is study the feasibility of using the modern method of near-infrared spectroscopy to study the vegetation history of chernozems, using previously collected databases (Vysloužilová et al. 2015) to extract information from new sites along the grassland-woodland boundary in Minnesota, USA. The results are then analyzed and compared to known information and the results of more traditional approaches.
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Formation of realgar at the Mokrsko
Rodovská, Zuzana ; Drahota, Petr (advisor) ; Filippi, Michal (referee)
Summary: Throughout the world there are many places with a high concentration of arsenic in water. In the Czech Republic is such a place the area of Mokrsko, where arsenic in groundwater reaches the values, which are well above recommended limits for drinking water. On the studied locality arsenic is bound to secondary minerals containing iron; however, in the reducing conditions of the fluvial sediments arsenic is bound to newly-formed realgar accumulations associated with organic matter. Aim of this diploma thesis was to characterize realgar from this locality and try to determine the way and conditions of its origin. For the purpose of research, realgar and pore- water have been sampled, using lysimeters and rhizon samplers. Specimen of realgar was characterized by numerous standard techniques (XRD, SEM, TEM, chemical and isotopic composition). Water samples have been analysed for As, F and S species. Analysis of realgar using XRD, SEM and TEM techniques confirmed the presence of nanocrystalline realgar, forming clusters and needle like aggregates. Domination of divalent iron and reduced form of As3+ (4,3-7,3 mg/L) in similar concentrations has been observed within the pore- water samples. The concentration of dissolved sulfide was very low (cca 30 µg/L), on the other hand, content of sulphate was always...
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Use of stable isotopes in hair for understanding nutrition and population migration
Tomášková, Anežka ; Brůžek, Jaroslav (advisor) ; Kovačiková, Lenka (referee)
The analysis of stable isotopes of teeth and bones shines a new light on bioarcheology, understanding of nutrition as well as mobility of mankind in past. However studying stable isotopes which can be found in animal or human hair (carbon - δ13 C, nitrogen - δ15 N, oxygen - δ18 O and probably more) provide information of the same quality. This kind of information is not enriching only to bioarcheology, but also to other fields connected to antropology such as forensic science or medicine. This paper delivers basic overview of principles of determinig the content of stable isotopes in biological material and show advantages and disadvantages of using hair. Information which are used for further understanding of nutrition, mobility and geo-origins are demonstrated on examples from bioarcheology, forensic and clinical medicine.
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Preparation of radiolabelled bilirubin
Čepa, Adam ; Smrček, Stanislav (advisor) ; Moša, Marek (referee)
This thesis is dedicated to reasearch in radiolabeling bile pigment bilirubin. Minority bilirubin present in the body the form unconjugated. In this work, it was crucial synthesize radiolabeled bilirubin which could be monitored by detector in vitro experiments. A possible further applications, such bilirubin would be detectable in vivo experiments using µ-PET/SPECT (micro- positron emission tomography/single photon emission computed tomography) . The aim of this thesis propose variation for possible signs of bilirubin radioisotopes and synthesis of bilirubin derivates suitable for radioactive labeling. Another objektive of this work is the synthesis and study of the well-known derivative ranarubin called bilirubin, which could potentially have very simile characteristics, such as bilirubin and therefore would be a good candidate for radioisotope labeling and study of biological systems.
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