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Luminiscence of uranyl minerals and possibilities of its use as an analytical method
Cenek, Ondřej ; Goliáš, Viktor (advisor) ; Zachariáš, Jiří (referee)
This paper deals with the study of luminescence of uranyl minerals in ultraviolet radiation. Mineral samples of metaautunite, schröckingerite, natrozippeite and saléeite were studied. Twenty samples were selected for research and they were unambiguously determined using X-ray diffraction and energy dispersive spectrometry. For each sample, a luminescence spectrum was taken at 405 nm excitation radiation. Luminescence spectra were analyzed. The luminescence spectra of metaautunite contain 6 energy maxima. The maximum with the highest intensity is at an average position of 525.1 nm. Anomalous values are shown by two samples with an admixture of metauranocircite. The luminescence spectra of saléeite show a shift to lower wavelengths compared to metaautunite, caused by a change in the main cation (Ca - Mg). The spectra of saléeite show 5-7 energy maxima and the maximum with the highest intensity is at an average position of 521.2 nm. The spectra of schröckingerite contain 8-9 energy maxima and the maximum with the highest intensity is at an average position of 505.4 nm. An anomalous spectrum is shown by a sample with liebigite admixture. The luminescence spectra of natrozippeite are different compared to the other minerals used in this work. The spectra do not show isolated energy maxima, but one broad...
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Nutritional intake of macroelements in lactating women.
Doubková, Zuzana ; Hronek, Miloslav (advisor) ; Jílek, Petr (referee)
The thesis deals with the issue of nutrition in lactating women. The main objective of this work is to conduct a comprehensive analysis of the nutritional intake of Czech women during lactation, focusing on the intake of selected minerals, specifically sodium, potassium, calcium, magnesium, and phosphorus. Subsequently, the obtained results will be compared with the recommended daily intake of these macroelements. The results are based on the nutritional intake of six monitored women, from whom values were provided for all lactation periods L1 to L4 during the period from February 2022 to February 2023. For a larger dataset, the values of two additional women were included in the research, from whom values were obtained for periods L1 to L3. Further details of this limitation are provided in the relevant chapter 7.1.7. Limitation of the study. Women recorded their diets in questionnaire form, always a week before visiting the physiological laboratory of Professor PharmDr. Miloslav Hronek Ph.D. In the questionnaire, they recorded meals, foods, fluids, and their intake amounts. The gathered information was further processed using the NutriDan program and statistically evaluated in the Microsoft Excel program. A key finding of the study is an excessive intake of sodium, approximately 1000 mg of sodium...
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Automatic classification of geological samples using Laser-Induced Breakdown Spectroscopy and machine learning
Stříbrná, Klára ; Hrdlička, Aleš (referee) ; Prochazka, David (advisor)
This thesis focuses on creating a database of LIBS spectra from geological samples. These spectra are then used to train a Convolutional Neural Network (CNN)-based classification model for the automatic classification of the samples. The trained models are validated on unknown data and compared in terms of accuracy and training time. The aim of the thesis is to evaluate the potential of combining LIBS with Machine Learning for the automatic classification of geological samples. Current methods are often time-consuming and expensive. LIBS allows for fast chemical mapping and, compared to other methods of chemical analysis used in geology, is relatively inexpensive. Additionally, LIBS can detect light elements (such as Li and Be) that are undetectable by other methods.
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Basic characterization of selected samples of animal feeds
Svoboda, Ilona ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
The aim of the diploma thesis was to choose poper parameters for a quick and simple characterization of animal feed, to verify working procedures and to apply these on chosen samples. Within the scope of this work, samples of animal dog feed produced in a private company „Adamkovy tlacenky“ were analyzed. The feed is in the form of brawn, stored in artificial casing; it consists of up to 80% of animal components and up to 20% of vegetable components, while the rest of the weight is the pork gelatine. The feed does not contain preservatives, colourings as well as any other chemically produced additives. For the analysis three formulas were chosen: "Hovězinka", "Kuřátko" and "Srdcovka", the composition of which is protected by the patent. The choice was made to include samples of different composition. The content of raw crude protein, fat, fibre, dry basis, and ash was determined. The obtained values were compared with the standards for feed normally utilized by the feed industry. The results will be used to improve the formulas and to develop new types of feed.
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Nutritional benefit of cricket flour
Šťastná, Martina ; Zemanová, Jana (referee) ; Němcová, Andrea (advisor)
Edible insects have been part of the diet of many countries across the world for several decades. It is becoming increasingly popular in the europian developed countries, mainly because of the content of nutritionally important substances. The theoretical part of the thesis deals with the characterization of edible insects in terms of nutritional benefits, explains the reasons and method of breeding edible insects. For the analysis of nutritionally active substances, flour of house cricket (Acheta domesticus) was used. A. domesticus belongs to the representatives of insects legalized from 1.1. 2018 on the EU market. Of the significantly nutritional substances, proteins, lipids, fatty acids, fiber and selected minerals were analyzed. In this study, optimalization of vertical electrophoresis SDS-PAGE was performed to determine protein fragment sizes. In the second part the influence of acricket flour addition protein bars was investigated by sensory analysis. In the experimental part that was found that cricket flour contains protein, lipids and fatty acids in significant amounts. It also contains important minerals for human health such as magnesium, potassium, iron or zinc. However, the sensory properties of protein bars for consumers were not very attractive.
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Determination of the risk elements and other elements concentration in animal feed
Křehlíková, Jana ; Juglová, Zuzana (referee) ; Diviš, Pavel (advisor)
This thesis deals with the determination of selected microelements and macroelements and risk elements in dog and cat food. The theoretical part describes the nutrition of dogs and cats and focuses on the safety of the food in the context of contamination with risk elements. Another topic discussed is the chemical analysis of feeds, specifically the determination of nutritionally important substances, beneficial elements, and contaminants. The experimental part deals with the preparation and digestion of feed samples and the subsequent analysis of these samples using ICP-OES and AAS methods. The detected concentrations of the elements of interest in the feeds were compared with the feed standards issued by the Department of Veterinary Medicine and the decree issued by the Ministry of Agriculture. The analysed feeds were found to be deficient in some elements. The content of the risk elements in the feed met the legal limits and did not pose a health risk to the animal. Elements for which the legislation does not provide a maximum permissible limit were present in the feed-in in high concentrations that could already harm the animal's health.
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Landscape of mining
Frič, Miloslav ; Ryška, Pavel (referee) ; Vaněk, Vojtěch (advisor)
The landscape of surface mining is a visual play that expoits the land on this large format drawing. My work investigates the limits of hanged art piece through the use of video projection and camera. The spectator is not limited by a clear thought framework but urged to experience a visual experience in this very place and time.
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The study of various methods of preparation of the milk sample for milk analysis by ICP-OES technique
Kaňová, Veronika ; Vítová, Eva (referee) ; Diviš, Pavel (advisor)
The theoretical part of the thesis deals with the chemical composition of cow’s milk, with the description of chosen methods of sample pretreatment and with the description of the used technique ICP-OES. The practical part is aimed at individual preparations of samples and at analysis of chosen chemical elements (Ca, Na, K and Mg). Milk is a really complicated polydisperse system, that’s the reason why the preparation of samples with milk is very important step before the measurement itself. In addition to accuracy choosing the sample adjustment method, other factors such as time, work intensity, or cost need to be considered when. In the thesis a comparison of four selected methods of sample preparation was made: direct analyse of milk, dilution with addition of Triton X-100, wet microwave ashing and destruction of matrix with TMAH (tetramethylammonium hydroxide). Selected elements were analysed with the help of ICP-OES. This diploma thesis builds on the bachelor thesis, which deals with the same problem. Final concentrations were compared with certified values of skimmed powdered milk. Data showed that the most accurate are methods of preparation of wet microwave ashing and destruction of matrix with TMAH. By using these methods, the effect of the dairy matrix that caused problems in the analysis, was largely eliminated. The diluted samples with and without Triton X-100 showed a bigger anomaly of measuring than the mineralization of wet ashing which came to the loss of analyte because of fat elements contained in milk.
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Organomineral gel as a new concept of structural and colloidal characterization of soils
Kundera, Ondřej ; Záhora, Jaroslav (referee) ; Sedláček, Petr (advisor)
The aim of this study is the organomineral gel contained in soil, mainly the characterization using electron microscopy and available analytical methods like IR-spectrometry, thermal analysis, X-ray crystallography and emission spectrometry. The knowledge from this study may help to define function and significance of this gels to soils and nature. The theoretical part of this thesis deals with soil, humic substances and minerals occurring in soils. The experimental part solves especially the structure and further characterization of organomineral gels.
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Analysis of milk by ICP-OES technique
Kaňová, Veronika ; Hrstka, Miroslav (referee) ; Diviš, Pavel (advisor)
The theoretical part of the thesis deals with the chemical composition of cow’s milk, with the description of chosen methods of sample pretreatment and with the description of the used technique ICP-OES. The practical part is aimed at individual preparations of samples and at analysis of chosen chemical elements (Ca, Na, K, Mg a P). Milk is a really complicated polydisperse system. The preparation of samples with milk is very important step before the measurement itself. In the thesis a comparison of four selected methods of sample preparation was made: bare dilution, dilution with addition of Triton X 100, wet ashing and sonication. Selected elements were analysed with the help of ICP-OES. Final concentrations were compared with CRM of dried milk. Data showed that the most accurate are methods of preparation of diluted sample and wet ashing. Four different types of milk were analysed with the help of those two selected methods. The diluted samples showed a bigger anomaly of measuring than the mineralization of wet ashing which came to the loss of analyte because of fat elements contained in milk.
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