National Repository of Grey Literature 51 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Analysis of thermal power plants environmental impacts using radioanalytical methods
Král, Dušan ; Ing. Ondřej Huml, Ph.D., KJR FJFI ČVUT v Praze (referee) ; Katovský, Karel (advisor)
Operation of classical power sources, like coal fueled thermal power plants, causes more or less strong impact on surrounded environment. Beside to the generally discussed CO2 emissions, there are CO, SOx, NOx too; and also fly ash emissions containing various trace elements depending on coal quality. Heavy trace elements carried by fly ash generate locally distributed fallout and contaminate soil in the power plant neighborhood for many years. These elements may be detected in soil samples as well as in biomass. Objectives of this work are to find and quantify trace elements in soil samples near Oslavany hard coal fueled thermal plant, which was in operation from 1913 to 1993. Power plant did not use any advanced fly ash filters. Hard coal was used as a fuel for power plant and it was mined locally in Rosice-Oslavany coal district in very deep mines (up to 1428 m). Coal contained a lot of trace elements. A mine as well as power plant is for more than 20 year closed, but trace elements can be still find in the environment. Main goal is to find these elements using activation analysis and gamma-ray spectrometry methodology. We have assembled thirty six soil samples in square lattice drawn around Oslavany power plant brownfield. On behalf of cooperation with colleagues from the Czech Technical University in Prague and their Open-Access project, we irradiated samples in three vertical channels of VR-1 research nuclear reactor. Irradiated samples were transported to gamma spectroscopy & activation analysis laboratory and measured by HPGe detector. Gamma spectra were analyzed and some trace elements identified. We have determine relative and absolute concentration of found elements. We observe and determine activity and weight of As, U, Ba, La, Eu, Mn, K, V, Mg and Na only. Results show a real suspicion for increase of trace elements in soil samples of hard coal power plant surroundings.
Analytical methods for verifying the authenticity of the wine
Flegr, Šimon ; Štursa, Václav (referee) ; Diviš, Pavel (advisor)
This bachelor’s thesis deals with the authenticity of wine, focusing on the authenticity of geographic origin. The theoretical part of this work summarises the main components of wine and their changes during the production proces. Control techniques are introduced, including the ones used by the goverment’s control bureau (SZPI) and other documented methods. Areas recognised for growing wine are described, including the Morava area in Czechia and its imminent adjacent areas in Austria and Slovakia. Experimental part deals with the trace amount analysis of selected elements and phenolic compounds. The element analysis was conducted using mass spectrometry and optical emission spectrometry, whilst the phenolic compounds were separated using high-pressure liquid chromatography with spectrophotometric detection. The results were analysed using discrimination analysis to separate groups with different areas of origin, with the aid of data from former research.
Studying the authenticity of coffee of various geographical origins
Flegr, Šimon ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This diploma thesis researches coffee authenticity problematice, mainly focusing on the authenticity of geographic origin. In the theoretical part of this work, botanical classification is described as well as production technology and processes. The work also includes chemical composition of coffee, describing the major components and changes during production phases. It describes major production areas of the world, in terms of general description and brief history. Problematics with coffee fraud and its identification are also described. Theoretical part also includes general geological description of 17 studied coffee growing regions. Experimental part is devoted to trace amount analysis of selected elements and volatile compounds. The element analysis was conducted using mass spectrometry or optical emission spectrometry, volatile compounds were determined using gas chromatography combined with mass spectrometry detection. Results were statistically described and analyzed, resulting in several discrimination models based on geographic origin.
Vliv vybraných minerálních prvků ve vztahu ke krevnímu obrazu u skotu.
DRESLER, Sylva
The aim of the current doctoral thesis is to evaluate the influence of the composition of a total mixed ration supplemented with dietary, organically bound zinc on health status and related hematological and biochemical parameters and mineral levels in blood in cows and their calves. The experimental part is divided in two subareas. The first experiment is monitoring the effect of supplementation of the organic form of zinc on lactation performance of cows and effect of TMR composition on the blood parameters of the hematological, metabolic, and mineral profile of cows and their calves. The second experiment is focused on an effect of the addition of organic zinc on blood parameters, health, and immunological status of weaned calves - metabolic profile, concentration of vitamins A and E, trace elements Cu and Zn, and total immunoglobulin levels in blood serum.
Variscan subduction-related plutonism in the French Massif Central
Usmanova, Diana ; Janoušek, Vojtěch (advisor) ; Špillar, Václav (referee)
The French Massif Central belongs to the Moldanubian Zone, which is an internal part of the Variscan Orogen. The Massif was formed during six tectonic-metamorphic events and has a nappe structure. The Muscovite-bearing Peraluminous Granitoids (MPG), Cordierite-bearing Peraluminous Granitoids (CPG), K-rich Calc-alkaline Granitoids (KCG), and Amphibole-bearing Calc-alkaline Granitoids (ACG) types of granitoids were intruded into the nappe units during the Carboniferous. The formation of FMC granitoid plutons was predominantly linked to continental collision; only the ACG plutonites are older, typical of magmatic arcs. These amphibole-bearing calc-alkaline quartz diorites to tonalites are common in the western French Massif Central (Limousin region), where a 250 km long belt known as the "Limousin tonalite belt" is found. Its linear shape and characteristic geochemical composition suggest a subduction-related origin. Newly obtained geochemical data from the Limousin region indicate an intermediate composition (52-57 wt% SiO2), a metaluminous, subalkaline character, and place the samples in the calc-alkaline series. Furthermore, enrichment of Large Ion Lithophile Elements (LILE), depletion of High Field Strength Elements (HFSE), negative europium anomaly (Eu/Eu* = 0,63-0,92) and relatively low initial...
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...
Diel variations of selected elements in arsenic-rich stream at the Mokrsko
Nováková, Barbara ; Drahota, Petr (advisor) ; Skřivan, Petr (referee)
The filtration and ultrafiltration experiment was applied on the stream water at the Mokrsko gold deposit and the results revealed that most of the elements were in the dissolved form and the 0,45 or 0,1 m filters could be used. During two 24-h field experiments, water samples were collected at 1-h intervals in order to prove the diel changes in the concentration and speciation of several trace elements. The determination of sorption processes at the surface of or within the veneer of biofilm has been determined by collecting natural and artificial priphyton. The results showed regular diel changes of As, Sb and Mo with highest concentrations occurring after the moon and the lowest concentrations in the early morning. The dissolved concentrations of other elements are conservative or their values were closed to their detection limits. The diel cycles are caused by changes in adsorption/desorption equilibria induced by diel cycles of temperature. The samples of biofilm revealed increased concentrations of the elements under the study and their diel variation were significant (approximatelly 35-96%); however, biofilm-controlled diel cycles of dissolved concentrations have not been proved.
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...
Trace and minor elements in coal and methods of their investigation
Páchová, Helena ; Opluštil, Stanislav (advisor) ; Sýkorová, Ivana (referee)
The aim of the bachelor thesis is to provide an overview of the minor and trace elements in coal matter and to characterize their origin, distribution and effect on quality of coal in term of its industrial utilization, including potential environmental impacts. The thesis describes main methods currently used when investigating coal geochemistry and mineralogy. The thesis includes overview of the distribution of these elements in the major coal deposits of the Czech Republic.

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