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Exogenic alteration of geomaterials with anomalous content of hazardous elements
Udatný, Martin
of dissertation thesis Exogenic alteration of geomaterials with anomalous content of hazardous elements The research of waste materials from high temperature processes belongs to current issues solved in the field of modern environmental geochemistry. Current research has mainly been focused on fly ash and bottom ash coming from metallurgy, combustion and other industrial processes. In these wastes of different grain size, accumulation of hazardous elements occurs. These elements may be present in low concentrations in combusted coal or municipal solid waste or it may come from ore processing. Hazardous compounds are also intentionally added during the technological process (e.g. making of lead glass). Modern industrial plants are equipped with effective filtration systems, but this might not be in the past. In the Czech Republic and elsewhere in the world old environmental burdens are and will be addressed. Current modern filtration systems are never 100% efficient. Contamination of surrounding environment in a lesser extent can still occur. The production of lead glass (Bohemian Crystal) is based on the addition of lead compounds in the glass raw material. Additions of these substances providing a high refractive index of the finished product. Also compounds containing other hazardous elements...
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Exogenic alteration of geomaterials with anomalous content of hazardous elements
Udatný, Martin ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee) ; Vaněk, Aleš (referee)
of dissertation thesis Exogenic alteration of geomaterials with anomalous content of hazardous elements The research of waste materials from high temperature processes belongs to current issues solved in the field of modern environmental geochemistry. Current research has mainly been focused on fly ash and bottom ash coming from metallurgy, combustion and other industrial processes. In these wastes of different grain size, accumulation of hazardous elements occurs. These elements may be present in low concentrations in combusted coal or municipal solid waste or it may come from ore processing. Hazardous compounds are also intentionally added during the technological process (e.g. making of lead glass). Modern industrial plants are equipped with effective filtration systems, but this might not be in the past. In the Czech Republic and elsewhere in the world old environmental burdens are and will be addressed. Current modern filtration systems are never 100% efficient. Contamination of surrounding environment in a lesser extent can still occur. The production of lead glass (Bohemian Crystal) is based on the addition of lead compounds in the glass raw material. Additions of these substances providing a high refractive index of the finished product. Also compounds containing other hazardous elements...
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Methodology for separation and isotope analysis of magnesium in selected geomaterials
Francová, Michaela ; Farkaš, Juraj (advisor) ; Chrastný, Vladislav (referee)
An efficient methodology for separation of magnesium from different geomaterials was developed in order to determinate their isotopic composition. This methodology with 100% yield is suitable for high precision analysis of Mg isotopes by multi collector inductively coupled plasma mass spectrometry (MC-ICP-MS). Three separate stages of ion-exchange chromatography were carried out in ultra-trace laboratory equipped with laminar flowbox using cation exchange resin, AG50W-X12 and chemicals of ultrapure quality. Variations in samples 26 Mg/24 Mg and 25 Mg/24 Mg ratios are expressed as δ26 Mg and δ25 Mg units, which are deviations in parts per 103 from the same ratio in DSM3 Mg standard. The robustness of the technique was assessed by replicate analyses of magnesium standards Cambridge 1 versus DSM3. The long term repeatability of the Mg isotope ratio measurements of Cambridge 1 against DSM3 using this technique is -2.577 ± 0.10‰ on δ26 Mg and -1.328 ± 0.06‰ on δ25 Mg at 95% of confidence (2σ). Delta 26 Mg in five natural standard samples was measured in order to validate a quality of measurement in two different laboratories: Czech Geological Survey, Prague, Czech Republic and GFS Potsdam, Research centre for geoscientist, Potsdam, Germany. The results measured in this study (laboratory of CGS) are...
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Methodology for 3D visualization of buildings and structure of geomaterials using industrial X-ray computed tomography - principles for ensuring the quality of tomographic data
Souček, Kamil ; Staš, Lubomír
Worked out methodology was created for the determination of the basic procedures designed for obtaining the best possible quality tomographic data using X-ray computed tomography. The methodology was created for the needs of 3D visualization of the geomaterials internal structure (eg. rock, soil, building materials, goecomposites etc.) and for the purposes of carrying out qualitative and quantitative non-destructive material analysis of 3D internal structure of investigated geomaterials. Obtaining the high-quality tomographic data represents primarily the process of setting various parameters of X-ray CT scanners, which are described in this methodology. The indisputable advantage and the novelty of this methodology present its non-destructivity and possibility for analysis of investigated geo-materials in three-dimensional space. The methodology has been prepared and it can be used for two types of X-ray CT scanners from Nikon Metrology NV company XT H 450 2D/3D and XT H 225 ST.
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