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HG-AAS s atomizací v plazmovém výboji s dielektrickou bariérou: optimalizace metody a analytické aplikace / HG-AAS with atomization in a dielectric barrier plasma discharge: method optimization and analytical applicationsZurynková, Pavla January 2016 (has links)
The aim of this diploma thesis was to optimize in detail atomization conditions for antimony hydride in a novel plasma atomizer based on a dielectric barrier discharge (DBD) with atomic absorption spetrometric detection. Argon was found as the best DBD discharge gas employing a flow rate of 50 ml min-1 Ar while the DBD power was optimized at 30 W. Analytical figures of merit including interference study of As, Se and Bi have been subsequently investigated and the results compared to those found in an externally heated quartz tube atomizer (QTA). The limit of detection reached in DBD (0.15 ng ml-1 Sb) is comparable to that observed in QTA (0.14 ng ml-1 Sb). Finally, possibility of stibane preconcentration in a DBD atomizer was studied. Preconcentration efficiency of 102 ± 6 % was found under optimized conditions.
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Hormony v čistírenských kalech / Hormones in sewage sludgeJagošová, Klára January 2018 (has links)
Currently there is a spate of interest in the presence of pharmacologically active substances in the environment. These substances are excreted in active or metabolized form and with wastewater pass the wastewater treatment plant. Current treatment technologies do not always eliminate all pharmaceuticals effectively and therefore they enter the environment. One of these active groups is the group of steroid hormones. Steroid hormones belong to the group of endocrine disruptors and they are considered to be dangerous for the ecosystems. Due to the hydrophobic character of steroid hormones they undergo partial or total sorption from wastewater to sludge. Sewage sludge is the by product of wastewater treatment and contains heavy metals, organic contaminants and pathogenic bacteria. A part of produced sewage sludge is used as a fertilizer in the Czech Republic. This issue follows the regulation 347/2016 – conditions of agricultural use of sewage sludge. Waste policy of EU will alter the conditions of sludge disposal, so it is necessary to obtain data about the concentration levels, fate and behaviour of those pollutants. This thesis was focused on five natural female hormones and four synthetic, which are used as a part of contraceptive pills and substitutional hormonal therapy. Determination of hormones was performed in four steps including ultrasonic assisted extraction, clean up by solid phase extraction, derivatization and final analysis by gas chromatography with mass spectrometry on triple quadrupole in MS/MS mode.
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Analýza monitorování zemní hráze vodního díla Karolinka / Analysis of the earth dam monitoring of the water structure KarolinkaKoudelková, Eva January 2019 (has links)
This diploma thesis deals with the analysis of the monitoring of the Karolinka water reservoir earth dam. For the reason of seepage detected on the downstream face of the dam, the water reservoir was operated in a limited regime practically from its beginning. One of the most significant interventions aimed at reducing them was the installation of a sealing wall realized in 2013. Since 2011, the earth dam has been pilot-monitored by probes of the electrical impedance spectrometry method. The thesis deals with the processing of the data obtained by this method and with the comparison of the determined electrical conductivity of the dam soil with the data measured on the earth dam (temperature, water level in the reservoir, seepage) before and after installation of the sealing wall.
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Kvantitativní analýza matricových prvků metodami SIMS a LEIS / Quantitative analysis of matrix elements using SIMS and LEIS methodsStaněk, Jan January 2019 (has links)
This thesis studies comparison and connection of two spectrometric methods – low energy ion scattering spektrometry (LEIS) and secondary ion mass spectrometry (SIMS). SIMS method, despite its many positive qualities, suffers of so called matrix effect, which makes quantifiaction of data very difficult. LEIS method on the other hand is immune to this effect and so it’s suitable completion of SIMS method. As a convenient sample have been chosen AlGaN samples with various concentration of gallium and aluminium. In the first part of thesis is introduced physical essence of SIMS and LEIS method, experimental details and studied samples. In second part of the thesis there’s a description of measurements and comparison of data gained by each method.
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Analýza monitorování zemní hráze malé vodní nádrže / Analysis of the earth dam monitoring of a small water reservoirKrálíková, Štěpánka January 2020 (has links)
The diploma thesis deals with the use of the electrical impedance spectrometry method (EIS) and the devices Z-meter II, Z-meter III and Z-meter VI based on it for the monitoring earth-fill dams of small water reservoirs. The devices were developed in the Laboratory of Water Management Research of the Institute of Water Structures of the Faculty of Civil Engineering of the Brno University of Technology by solving international project of applied research in the EUREKA program. The analysis of monitoring of the dam of the small water reservoir Bezedník III, which is located in the cadastre of the village Kobeřice, was carried out. Monitoring was carried out from 2006 to 2012. One-off control measurements followed by analysis of achieved results were carried out in 2016, 2018 and 2019.
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Studium chování nanočástic platiny ve složkách životního prostředí / The study of behavior of platinum nanoparticles in environmental compartmentsBerka, Michal January 2020 (has links)
Platinum nanoparticles pose a risk to environmental compartments. The aim of this diploma thesis is to conduct research on the influence of platinum nanoparticles in a wide range of concentrations on soil properties at different humidities. Specifically, it is about influencing the stability of water molecular bridges, the content of aliphatic crystallites, the retention capacity of water in the soil and the strength of water binding. Furthermore, the amount of nanoparticles sorbed on the soil was also measured. These indicators give us more information about the influence of platinum nanoparticles on evapotranspiration and soil deterioration. Methods of thermal analysis (differential scanning calorimetry) and optical methods (atomic absorption spectrometry) were used for these researches. The theoretical part of the work is devoted to a comprehensive introduction to platinum and its nanoparticles, as well as aqueous molecular bridges. It has been found that 200 nm platinum nanoparticles affect the strength of aqueous molecular bridges, have no effect on aliphatic crystallite content, have minimal effect on soil water retention, and that the water bond strength decreases due to platinum nanoparticles at high relative humidity. With 200 nm platinum nanoparticles, complete adsorption to soil occurs over the entire concentration range. With 3 nm nanoparticles, the soil is supersaturated at higher concentrations and larger amounts are not adsorbed. The results show that the larger the size of the platinum nanoparticles, the lower the negative effect on evapotranspiration and soil function itself.
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Rozměrová, tvarová a materiálová analýza bimetalových dílců s definovaným poloměrem ohybu / Dimensional, Shape and Material Analysis of Bimetal Parts with Defined Bending RadiusIvánek, Radim January 2020 (has links)
The thesis aim is an evaluation of achieved results coming from the analysis of pipe bend 180° for the critical bending / bend 1D and supercritical bending / bend 0,7D. The theoretical part is focused on material property of a bimetallic pipe and on methods applied to work out the analysis. The definition of critical points at a considered segment and possible defects arisen while bending is embodied in the thesis. The practical part of the thesis is based on presenting dimensional and proportional analysis based on using optical microscopes and 3D scanner GOM ATOS. The material analysis was aimed at macrostructure as well as microstructure of the bimetallic pipe material, at chemical composition and at the hardness when low-loaded. The analysis achieved results are assessed at the end of the thesis.
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Charakterizace rostlinné složky vybraných potravin pomocí technik molekulární biologie a instrumentálních metod / Characterization of plant-based component of selected foodstuffs using techniques of molecular biology and instrumental methodsTomíšek, Martin January 2020 (has links)
The aim of this work was to compare authenticity analysis in selected food products with fruit component by using, instrumental and molekular methods. Particularly, the presence of blueberries in fruit–based foodstuffs was verified. The theoretical part is focused on the characterization, chemical composition and botanical classification of blueberries (European blueberry and Canadian blueberry). It also contains an overview of instrumental and molecular diagnostic methods that can be used for the analysis of these fruits. The experimental part focuses on the selection of a suitable method of DNA isolation, and primers for the detection of blueberries in commercial products. DNA analysis was performed by qPCR and HRM analysis. In the experimental part, DNA was isolated in sufficient quality for PCR and the presence of blueberries in foodstuffs was verified by qPCR. Using HRM analysis, we were able to differentiate between bilberry (Vaccinium myrtillus) and blueberry (Vaccinium corymbosum) in control samples and in some commercial products. Certain phenolic acids and some flavonoids specific for blueberries were detected by HPLC. The total content of polyphenols and flavonoids was determined by UV / VIS spectrophotometry.
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Experimentální a výpočetní výzkum vlastností solí pro jaderné reaktory typu MSR z pohledu jaderných dat / Experimental and calculational salts' properties investigation for MSR reactors from nuclear data point-of-viewBurian, Jiří January 2021 (has links)
Nowadays there is research into molten salt reactors. The use of chlorine-based salts, which would be more available than known fluoride salts, is envisaged. The subject of research is not only the chemical and physical properties of chloride salts, but also their behavior in the neutron field and the influence of neutron balance inside the reactor. Many properties can also be determined using calculations that draw information from scientific nuclear libraries (endf). The purpose of this work is to compare important nuclear libraries with each other, and also to compare the reaction rates calculated from the library data with the reaction rates obtained by self-measurement. The preview will include a description of the necessary activities associated with the preparation of measurements, instructions for compiling the computer program NJOY and the process of the measurement itself. At the end of the work will be summarized the results and statements of which nuclear library is the closest in its values to the results of experiments.
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Detekce a lokalizace mikrobiálních kolonií pomocí algoritmů hlubokého učení / Detection and localization of microbial colonies by means of deep learning algorithmsČičatka, Michal January 2021 (has links)
Due to massive expansion of the mass spectrometry and constant price growth of the human labour the optimalisation of the microbial samples preparation comes into question. This master thesis deals with design and implementation of a machine learning algorithm for segmentation of images of microbial colonies cultivated on Petri dishes. This algorithm is going to be a part of a controlling software of a MBT Pathfinder device developed by the company Bruker s. r. o. that automates the process of smearing microbial colonies onto a MALDI target plates. In terms of this thesis a several models of neural networks based on the UNet, UNet++ and ENet architecture were implemented. Based on a number of experiments investigating various configurations of the networks and pre-processing of the training datatset there was chosen an ENet model with quadruplet filter count and additional convolutional block of the encoder trained on a dataset pre-processed with round mask.
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