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Preparation of WDXRF analysis cement tablets
Kozlová, Romana ; Lerch, Jiří (referee) ; Svěrák, Tomáš (advisor)
This bachelor's thesis is focused on the sample preparation for the X-ray fluorescent analysis (XRF) of cement. The thesis aims to contribute to finding optimal method of the sample preparation of cement in the form of tablets, which would then provide the most accurate XRF analysis. This activity is related with finding a method of the sample preparation with an appropriate granulometry and homogeneity of the powder material, and also is related with creating the conditions of pressing of this material in the form of compact tablets, which are not prone to fracture. Selected problem was solved by adjusting twenty possible parameters of the mill and press. The milling was evaluated by granulometric composition of the sample, which was determined by a laser diffraction. For the smallest sample the repeatability of measurement was performed. Sieve distribution was used to achieve a finer sample, followed by XRF analysis. Tests of strength of samples pressed into ringlets were performed using a three-point tensile strength in bending, for samples with the finest and most coarse composition. The chemical composition of the finest and most coarse sample, which was prepared by milling and also the sample after milling and sieve distribution, was verified with the XRF analysis. By combining the 20 parameters during the sample preparation, maximum accuracy of the XRF analysis was achieved. The final setting meet the granulometric requirements and also abrasive and strength tests of tablets after pressing the sample. The contribution of this work is an increase in accuracy of the XRF analysis to a better level than ever before. As a result the negative impacts, which directly affect he accuracy and reproducibility of the sample preparation for the XRF analysis, were minimized. The resulting sample preparation was applied to the laboratory of quality and quality control at Českomoravský cement a.s., Mokrá plant, for which this work has been performed.
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Study of particles of various cosmetic pigments
Cerevatova, Kristina ; Opravil, Tomáš (referee) ; Zemanová, Jana (advisor)
The main focus areas of this master thesis include the writing of a literature review, which contains an overview and segregation of pigments which are used in the preparation of cosmetic products. The thesis is focused on the properties and characterization of pigments for use in cosmetology. The following focus is on legislation, more specifically on pigments that the cosmetic industry allows, limits and does not allow. The main part of this thesis is an overview of methods for the characterization of pigments. The practical part deals with the characterization of particles of selected cosmetic pigments by applying methods for determination of color, elemental and phase composition, particle size and morphology. The thesis is concluded by evaluation of the achieved results.
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Mapování obsahů toxických kovů v zeminách v oblasti Hranic a Teplic nad Bečvou
Kotásková, Michaela
This thesis focuses on the occurrence of toxic metals, specifically Mo, Sr, U, Rb, Th, Pb, As, Zn, Cu, Ni, Cr, and V, in the soil environment of Hranice Karst. Forest soils, soils in the Bečva River valley, and arable soils were examined, with a focus on locations with possible contamination (waste landfill, cement plant). Samples were taken according to the manual for geochemical mapping, both from the surface and at a depth of 25 cm. Subsequently, concentrations of toxic metals were measured in the collected samples using an X-ray fluorescence spectrometer, and the basic geochemical properties of the samples were evaluated. The determined values and calculated pollution indices were compared with legislative requirements for limit concentrations of metals in soils, with a selected reference location (NPR Hůrka), and with each other. The work is supplemented with maps of the concentrations of individual elements in selected locations created in the Geographic Information System. The thesis concludes with the concentrations of measured metals and metalloids present in the soil, including the locations of their occurrence in relation to the nearby cement plant and municipal waste landfill. The mapped environment of the Hranice Karst has been evaluated as an environment with only slightly elevated levels of certain elements.
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Study of particles of various cosmetic pigments
Cerevatova, Kristina ; Opravil, Tomáš (referee) ; Zemanová, Jana (advisor)
The main focus areas of this master thesis include the writing of a literature review, which contains an overview and segregation of pigments which are used in the preparation of cosmetic products. The thesis is focused on the properties and characterization of pigments for use in cosmetology. The following focus is on legislation, more specifically on pigments that the cosmetic industry allows, limits and does not allow. The main part of this thesis is an overview of methods for the characterization of pigments. The practical part deals with the characterization of particles of selected cosmetic pigments by applying methods for determination of color, elemental and phase composition, particle size and morphology. The thesis is concluded by evaluation of the achieved results.
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Preparation of WDXRF analysis cement tablets
Kozlová, Romana ; Lerch, Jiří (referee) ; Svěrák, Tomáš (advisor)
This bachelor's thesis is focused on the sample preparation for the X-ray fluorescent analysis (XRF) of cement. The thesis aims to contribute to finding optimal method of the sample preparation of cement in the form of tablets, which would then provide the most accurate XRF analysis. This activity is related with finding a method of the sample preparation with an appropriate granulometry and homogeneity of the powder material, and also is related with creating the conditions of pressing of this material in the form of compact tablets, which are not prone to fracture. Selected problem was solved by adjusting twenty possible parameters of the mill and press. The milling was evaluated by granulometric composition of the sample, which was determined by a laser diffraction. For the smallest sample the repeatability of measurement was performed. Sieve distribution was used to achieve a finer sample, followed by XRF analysis. Tests of strength of samples pressed into ringlets were performed using a three-point tensile strength in bending, for samples with the finest and most coarse composition. The chemical composition of the finest and most coarse sample, which was prepared by milling and also the sample after milling and sieve distribution, was verified with the XRF analysis. By combining the 20 parameters during the sample preparation, maximum accuracy of the XRF analysis was achieved. The final setting meet the granulometric requirements and also abrasive and strength tests of tablets after pressing the sample. The contribution of this work is an increase in accuracy of the XRF analysis to a better level than ever before. As a result the negative impacts, which directly affect he accuracy and reproducibility of the sample preparation for the XRF analysis, were minimized. The resulting sample preparation was applied to the laboratory of quality and quality control at Českomoravský cement a.s., Mokrá plant, for which this work has been performed.
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