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Information System Assessment and Proposal of ICT Modification
Krätzer, Jan ; Novák, Lukáš (referee) ; Koch, Miloš (advisor)
This diploma thesis is focused on the appraisal of the current state and the proposal for changes of the selected company Masaryk University that serves as a supporting element for the employees who deal with the actions of legally compulsory service. The appraisal of the current state of the information system is based on the analysis; the change proposals were sumbitted to the employees who are responsible for the operation and development of the information system.
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Information System Assessment and Proposal of ICT Modification
Krätzer, Jan ; Novák, Lukáš (referee) ; Koch, Miloš (advisor)
This bachelor thesis deals with the assessment of the current situation of the information system of the company and it also focuses on the proposal of changes of this system in order to provide users more comfortable and faster work by its usage. The assessment of information system is based on the analysis and consultations with the firm's employees. The result of the solution was accepted by the CEO and the changes were valued as very beneficial.
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Atomization of hydride forming elements in dielectric barrier plasma discharges
Baranová, Barbora ; Kratzer, Jan (advisor) ; Hrdlička, Aleš (referee)
The aim of this diploma thesis was to optimize the atomization conditions of two hydride forming elements - bismuth and tellurium in dielectric barrier discharge (DBD) plasma atomizers using atomic absorption spectrometry (AAS) as a detector. Two types of electrode constructions of planar DBD atomizers were studied: glued and sputtered electrodes while two construction of high voltage power supply sources were investigated employing either a sinusoidal or square wave modulation of high voltage function. The effect of the gas phase dryer included in the apparatus upstream the atomizer was also investigated. A nafion membrane tube dryer was identified as the most effective one. Its efficiency was verified using optical emission spectrometry. With the nafion tube included in the apparatus, two main parameters of DBD atomizers were optimized: the voltage of the power supply source and argon flow rate, which served as a discharge gas. Using optimal conditions, analytical characteristics were determined for all atomizers used and these were subsequently compared with those achieved in an externally heated quartz (multi)atomizer (MM)QTA. In the case of bismuth, the optimal argon flow rate was determined to be 75 cm3 min-1 for all atomizers. The optimal value for the power supply source with sinusoidal...
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Modular design for in-atomizer preconcentration of hydride forming elements with AAS detection
Novák, Petr ; Kratzer, Jan (advisor) ; Korunová, Vlasta (referee)
Modular design of hydride trap-and-atomizer device for AAS is constructed and tested. Modular design enables to test different preconcentration surfaces easily. Efficient in- atomizer preconcentration allows to reach detection limits of hydride forming elements at ultratrace levels. Bismuth and arsenic were chosen as model analytes and their preconcentration efficiencies were quantified employing quartz and sapphire as preconcentration surfaces. The results reached in the modular design were compared to those found previously in the compact quartz trap-and-atomizer device. The performance of the modular design is fully comparable with that of compact trap-and-atomizer design. Modular design can thus be employed for testing of novel preconcentration surfaces.
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Optimization of chemical generation and subsequent atomization of volatile cadmium species for atomic absorption spectrometry
Sagapova, Linda ; Kratzer, Jan (advisor) ; Marschner, Karel (referee)
Generation and atomization of cadmium volatile compounds was optimized in this work in order to determine trace Cd concentration levels by volatile compound generation (VCG) with subsequent detection by atomic absorption spectrometry (AAS). Three designs of volatile compound generators have been tested including a conventional hydride generator in flow injection analysis (FIA) mode, a batch generator as well as a generator of volatile compounds of transition metals. The generation efficiency of Cd species was quantified as low as 4 % in the conventional hydride generator. Providing that dissolved oxygen was removed from the reaction solutions, the generation efficiency of Cd increased to 12 % in the same experimental arrangement. The highest Cd generation efficiency of 54 % was reached in the generator of volatile compounds of transition metals. In this set up a detection limit of 0.07 ng ml-1 Cd and a sensitivity of 3.2 s ng-1 Cd, respectively, were reached. Moreover, the structure of the volatile Cd species generated was identified as free atoms in all experimental arrangements of the generators investigated. Keywords atomic absorption spectrometry, cadmium, generation of volatile compounds, atomization of volatile compounds
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