National Repository of Grey Literature 49 records found  beginprevious20 - 29nextend  jump to record: Search took 0.01 seconds. 
Determination of selected metals in soils and mushrooms in the vicinity of the D1 highway.
HORÁKOVÁ, Tereza
The aim of the bachelor thesis was to determine the concentrations of heavy metals in edible mushroom samples and underlying soils. The elements measured were mainly copper, iron and zinc, followed by manganese, strontium and rubidium. The literature search contains brief information on each element and their content in soils and fruiting bodies of mushrooms in other studies. The theoretical part also includes chapters on fungi, soils and their contamination, the effect of vehicular traffic on the heavy metal content of soils and the used analytical method, which was atomic absorption spectrometry. For the practical part, 24 samples of eight different species of edible mushrooms were collected in the autumn of 2020 and 2021 in the vicinity of the D1 motorway. As part of the collection, the soil beneath the mushroom was also sampled to a depth of approximately 15 cm. The samples were first perfectly dried, then processed by microwave digestion, and finally analysed by AAS. All work was carried out in the laboratories of the Department of Applied Chemistry, Faculty of Agriculture and Technology, University of South Bohemia in České Budějovice. The results of the measurements were tabulated and processed statistically and graphically. Finally, they were evaluated in a discussion. The analysis showed that birch and birch goosefoot accumulate the least heavy metals in their fruiting bodies. The spruce budworm, the pink toadflax, the celandine and the brown mushroom accumulate metals on a large scale. In total, 4.2-45 mg.kg-1 dry weight Cu, 97,4-4166 mg.kg-1 Fe, 52,1-338,7 mg.kg-1 Zn, 3-61,4 mg.kg-1 Mn, 1,3-7 mg.kg-1 Sr and 7,7-300,9 mg.kg-1 Rb were measured in mushrooms. In soils, the values were as follows: 5,2-78,6 mg.kg-1 Cu, 2 965-41 983 mg.kg-1 Fe, 25,8- 174,2 mg.kg-1 Zn, 49,7-1 868 mg.kg-1 Mn, 6,2-25,2 mg.kg-1 Sr and 12,2-114,5 mg.kg-1 Rb in dry weight. These results show that strontium was the least represented heavy metal studied and iron was the most represented.
The content of the micronutrients in consumer eggs
DUŠOVÁ, Hana
The aim of the diploma work was to analyticly verify the actual status of the micronutrients (iodine, copper, zinc and manganese) in consumer eggs. The results of the research gives information about the content of the observed micronutrients in egg yolk and the importance of eggs as a source of these micronutrients for the nutrition of people. The eggs came from 13 small flocks and 7 large flocks in both 2007 and 2008. The average content of iodine in fresh matter of yolk of the eggs from the large flocks in 2007 was 1285,2 {$\pm$} 861,6 {$\mu$}g{$\bullet$}kg-1, zinc 63,71 {$\pm$} 31,08 mg{$\bullet$}kg-1, copper 7,42 {$\pm$} 4,88 mg{$\bullet$}kg-1 and manganese 1,02 {$\pm$} 0,84 mg{$\bullet$}kg-1. The average content of iodine in fresh matter of yolk of the eggs from the small flocks in 2007 was 387,1 {$\pm$} 214,3 {$\mu$}g{$\bullet$}kg-1, Cu 10,90 {$\pm$} 5,28 mg{$\bullet$}kg-1, Zn 73,54 {$\pm$} 44,33 mg{$\bullet$}kg-1 a Mn 1,28 {$\pm$} 0,75 mg{$\bullet$}kg-1. In 2008 the average concentration of iodine in fresh matter of yolk of the eggs from the large flocks was 1071,9 {$\pm$} 543,9 {$\mu$}g{$\bullet$}kg-1, Cu 20,63 {$\pm$} 8,85 mg{$\bullet$}kg-1, Zn 29,59 {$\pm$} 8,67 mg{$\bullet$}kg-1 a Mn 1,42 {$\pm$} 0,62 mg{$\bullet$}kg-1. In 2008 the average concentration of iodine in fresh matter of yolk of the eggs from the small flocks was 340,7 {$\pm$} 330,6 {$\mu$}g{$\bullet$}kg-1, Cu 17,95 {$\pm$} 6,19 mg{$\bullet$}kg-1, Zn 33,10 {$\pm$} 7,97 mg{$\bullet$}kg-1 and Mn 1,22 {$\pm$} 0,54 mg{$\bullet$}kg-1. The Eggs from the large flocks cover 6,8 {--} 13,5% of the daily iodine requirement in adults, 13 {--} 17,3% of copper, only 2,5 {--} 3,1% of zinc and 0,4 {--} 1,1% of manganese. The gained results imply that only the content of iodine in the egg yolk is evidently affected by the intake of it in the feeding rations, the intensity of the egg production and the stage of the laying cycle. The stated relations were not definite with the other elements. The concentration of iodine in the egg yolk was assessed spectrophotometrically by the method of Sandell {--} Kolthoff, modified by Bednář et al., (1964). The content of zinc, manganese and copper in the egg yolk were assessed by the method of atomic absorption spectroscopy (AAS).
Components of the environmental monitoring and its evaluation on the locality of MAPE Mydlovary.
NEJEDLÝ, Miroslav
On the locality of MAPE Mydlovary, where was fuctioning chemical concentrator of uranium ore, were made sludge beds. The sludge beds are significant landscape component, that dramatically take effects on the environment. That is why is important to pursue the monitoring to get the datas for detecting the influences of sludge beds on the environment. The aim of this dissertation is to evaluate the components of the environmental monitoring and state the results of recultivation on the locality of MAPE Mydlovary.
Determination of selected elements in coffee samples using ICP-MS method
Švecová, Pavla ; Hraníček, Jakub (advisor) ; Červený, Václav (referee)
EN The main aim of this thesis is focused on the determination of selected elements (manganese, copper, zinc, iron) in trace levels in selected samples of grained and instant coffee. Four samples of grained coffee and one sample of instant coffee were taken for analysis. Firstly, all samples were digested in a microwave digestion system and then analysed by inductively coupled plasma mass spectrometry to determine the concentration of selected elements. Except this, one sample of grained coffee was taken for two additional experiments. The aim of these experiments was to investigate the influence of the extraction time and temperature of water used for extractions, on the element concentrations in liquid phases. The content of elements in the analysed samples shows relatively wide range of values (7.58 - 34.4, 0.21 - 13.6, 1.58 - 5.35 and 12.2 - 55.8 µg/g for manganese, copper, zinc and iron, respectively). Generally, the lowest concentrations of all elements were detected in sample of instant coffee, which cannot be regarded as a valuable source of trace elements for humans. The first additional experiment shows that the concentrations of elements in grained coffee is much higher than in its extractions. With increasing time of extraction, the concentration of elements increased as well (except of...
Study of the content of risk elements in soils and plant material
Vlčková, Renáta ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the study of the content of selected heavy metals (Zn, Ni, Fe, Mn) in soils and mushrooms. The flame atomic absorption spectrometry method was used to determine the heavy metal content. Fungi and soil samples were collected at 18 sites in the Jeseníky region. The concentrations of heavy metals in the mushrooms were in the range from 140–582 mg/kg Zn, 48–380 mg/kg Fe, 5–19 mg/kg Mn and 3–8 mg/kg Ni. Zinc had the highest concentration value in all mushroom species. In soils, the concentrations of heavy metals ranged from 10–72 g/kg Fe, 52–1,000 mg/kg Mn, 29–115 mg/kg Zn and 6–50 mg/kg Ni. Iron was the most abundant element in the soils. Mushrooms contamination was assessed as a health risk in the study area. However, the pollution of forest soils was assessed as satisfactory and thus the productive function of the soil is not impaired. The type of forest cover was found to have minimal effect on the chemical composition of the soils.
Study of the effect of myocardial fibrosis on elemental distribution in rat soft tissues using Laser Ablation ICP-MS
Machalová, Martina ; Zlámalová Gargošová, Helena (referee) ; Vašinová Galiová, Michaela (advisor)
The most common cause of death in the Czech Republic continue to be cardiovascular diseases. The field of heart failure therapy still keeps moving forward. Yet myocardial fibrosis is one of the consequences and causes of heart failure for which there exists no effective medical care. The solution would be predicting the advancement of fibrosis and a preventive therapy. Many medical methods are being developed now in this regard, and the element distribution in affected tissue could help them. That is the reason why this work centers on the research of the element distribution in rat hearts with an induced myocardial fibrosis. An influence of sample couloration on the analysis was observed during its course. Special attention was paid to the distribution of iron in the fibrotic tissue as well as to the comparisson of the images of myocardial fibrosis. It seems that the iron distribution specificly could be helpful in recognising a damaged myocardium.
Determination of selenium and manganese in cerebrospinal fluid by atomic absorption spectrometry
Jiráková, Lucie ; Kotaška, Karel (advisor) ; Klapková, Eva (referee)
The aim of this study was to confirm the use of electrothermal atomic absorption spectrometry for the determination of selenium and manganese in the cerebrospinal fluid and to investigate concentrations of selenium and manganese in selected group of patients. For selenium was determined the detection limit 2,9 μg/l, for manganese 0,26 μg/l. 73 patients were examined (31 women, 42 men) whose average age was 14,1 years. The patients were divided into two groups according to age (56 children, 17 adults) and into two subgroups according to diagnoses (oncological, neurological). The control group consists of 18 subjects (5 women, 13 men, average age 21,7 years) with non-oncological and non-neurological diagnoses. We found significantly increased selenium concentrations in cerebrospinal fluid in the control group, compared with the group with neurological diagnoses (median = 14,4 μg/l vs. 12,4 μg/l, p < 0.05). Elevated levels of manganese in cerebrospinal fluid was observed in a group of children with oncological diseases compared with control group (1,2 μg/l vs. 0,5 μg/l, p < 0.05). Determination of selenium and manganese in the cerebrospinal fluid may have diagnostic importance in selected groups of patients. Powered by TCPDF (www.tcpdf.org)
Application of Atomic Absorption Spectrometry for Determination of Selected Elements from Potential Ecological Burden Area
Juránková, Lada ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
This work is focused on the determination of selected (chemical) elements (Fe, Mn, Zn, Cr, Na, K, Mg a Ca) in a potential ecological burden area using flame atomic absorption spectrometry as a detection technique. A potential ecological burden is represented by tires which are used as a construction material or as an environment surrounding for growing decorative and consumable plants. Analytes were determined in plant origin samples. Firstly, the samples were dried in a laboratory electric dryer. The weighted amount of a dried sample (approximately 0.2 g) was digested inside a microwave decomposition device with an addition of nitric acid and hydrogen peroxide. An optimization of experimental parameters was done for each of the elements before sample measuring. A burner height was optimized and 8 mm height was chosen as a optimum for most elements. Under the optimum condition basic characteristics were measured for each element separately. These characteristics included limits of detection that were: 0.05; 0.01; 0.08; 0.21; 0.02; 0.01; 0.01; 0.01 mg L-1 for the following elements: Fe, Mn, Zn, Cr, K, Ca, Mg and Na, respectively. The limits of quantification, sensitivity and repeatability were determined for each element as well. A significant attention was paid to the content of zinc in the studied...
The role of accumulation of iron and other metals in the pathophysiology of neurodegenerative diseases
Mašková, Jana ; Dušek, Petr (advisor) ; Vymazal, Josef (referee) ; Bártová, Petra (referee)
The role of metal accumulation in the pathophysiology of neurodegenerative diseases has been a hot topic in recent years due to the possibility of its treatment by chelating agents. Although the mechanisms of neurodegeneration are well known, the role of metal accumulation is still unclear. The main limitation are unsatisfactory methods for in vivo metal imaging; the most widely used technique is magnetic resonance imaging (MRI). Our aim was to assess the possibility of using transcranial sonography (TCS) in differential diagnosis of neurodegenerative diseases and to further explore the underlying factors of echogenicity. In the first study, using TCS fusion with MRI, we focused on location verification of the commonly assessed structures (substantia nigra and nucleus lentiformis) and exclusion of possible focal structural changes affecting the echogenicity in WD and PD patients. Moreover, obtained MRI were used for semi-quantitative comparison with TCS images. Although TCS has been confirmed to be highly beneficial in differential diagnosis of Wilson's disease and it should be recommended as a screening method for extrapyramidal patients with atypical course of the disease, the direct relationship between TCS and metal deposits could not be proven. The obtained results from the ultrasound fusion...
Design and synthesis of selective manganese(II) chelators
Míka, Luděk ; Kotek, Jan (advisor) ; Tauchman, Jiří (referee)
Title: Design and synthesis of selective manganese(II) chelators Autor: Luděk Míka Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: doc. RNDr. Jan Kotek, Ph.D. Supervisor's e-mail address: modrej@natur.cuni.cz Abstract:Abstract:Abstract:Abstract: The aim of this project is to synthetize new kind of macrobicyclic ligands derived from cross-bridged cyclam for complexation of Mn2+ ions. These complexes may be potentially used as contrast agents in magnetic resonance imaging. Three macrobicyclic ligand with various pendant arms were synthesized. The ability to complex manganese(II) ions were studied by Mass Spectroscopy. Electrochemical properties of manganese(II) complexes with general chelating agents and one synthesized ligand were studied using cyclic voltammetry. Keywords:Keywords:Keywords:Keywords: cross-bridged cyclam, phosphonate, phosphinate, pendant arms, manganese

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