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Quantitative Structure-Retention Relationships of Salicylthioamide Derivatives
Kalužíková, Aneta ; Nesměrák, Karel (advisor) ; Sobotníková, Jana (referee)
The aim of the thesis is to study the relationship between the structure of N-benzylsalicylthioamide derivatives and their retention behavior in high-pressure liquid chromatography. Furthermore, the influence of various substituents on electron absorption spectra in ultraviolet spectral range was studied. All studied derivatives have two absorption maxima in ultraviolet spectral range at 260 nm and 293 nm. The substitution of an auxochrome on the acyl ring leads to bathrochromic shift and hyperchromic shift, especially of the first absorption maxima. The presence of an auxochrome on the amide ring leads to hyperchromic shift as well. HPLC reversed-phase chromatography, using XDB-C18 ZORBAX column and mobile phase with various composition of acetonitrile, was used to obtain retention times of the derivatives. Using this data, the correlation equations between retention factor (mobile phase with no acetonitrile), resp. slope of the dependence of the logarithm of retention factor on the volume fracture of acetonitrile in mobile phase, and partition coefficient octanol-water, resp. hydrophobic substituent constants, were derived. Key words: QSAR, HPLC, spectrometry, benzylsalicylthioamides
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Mineralogical speciation of the radium isotopes in Karlovy Vary hot spring sediments: Results of the selective dissolution
Supiňková, Taťána ; Goliáš, Viktor (advisor) ; Smrček, Stanislav (referee)
Thermal waters in Karlovy Vary are characterized by carbonate sedimentation in places of their emergence. These sediments contain radium. Radium bond in every type of sinter (aragonite, calcite) has been investigated experimentally by acid sinter dissolution. It has been found out, that radium can join dissoluble fraction in both sinter types . The original hypothesis that radium can bond only aragonite-type of sinter has been refuted. Additional experiments have been processed using synthetic radiobarite. Present radium in radiobarite can be partly dissoluted using acids. If radium was incorporated in radiobarite (it is known from locality Vřídlo in Karlovy Vary and elsewhere) then maybe it would be partly dissoluted in experiments.
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Wedgewise correction for laser spectroscopy measurements
Schiffer, Štěpán ; Novotný, Jan (referee) ; Klus, Jakub (advisor)
One of the areas where LIBS is used is the creation of chemical maps of studied samples. Measurements made by this method are significantly influenced by the lens to sample distance. At the wedgewise samples this distance is changing during the measurement which decreases the quality of the chemical maps created. In this bachelor’s thesis a method of wedgewise correction is proposed and experimentally verified. A part of this thesis is a description of basics of laser spectroscopy and a summary of some variables influencing the LIBS experiment. The main part of the thesis is a proposal of wedgewise correction algorithm. At the end the results of measurement with the use of the proposed method are presented.
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Detection of Braking Tracks using Laser-Induced Breakdown Spectroscopy (LIBS) and Laser-Induced Fluorescence Spectroscopy (LIBS + LIFS)
Prochazka, David ; Vémola, Aleš (referee) ; Pína,, Ladislav (referee) ; Kaiser, Jozef (advisor)
The aim of this work is to investigate the potential of Laser-Induced Breakdown Spectroscopy (LIBS) for identification of visually unrecognizable braking tracks. Identification of these tracks is based on different chemical composition of tire tread in comparison to road surface. The investigation was divided in several sequential steps – selection of suitable chemical element and its spectral line for break tracks identification; determination of the limits of detection and threshold intensity respectively for the selected chemical element; verification of LIBS ability to detect braking tracks on a real braking track. This testing braking track was prepared by exactly defined and described conditions. The detection was performed in two ways – laboratory analysis of tire treads particles collected via adhesive tape and in situ analysis via mobile apparatus. Results of both measurements showed that LIBS is able to detect visually unrecognizable braking tracks. Concepts of the devices capable of routine braking tracks identification for both possibilities were introduced.
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RF detection method of explosives and drugs - NQR
Motyčka, Lukáš ; ČR,, MBA - ÚPT AV (referee) ; Kratochvíl, Tomáš (advisor)
The thesis deals with RF spectroscopic methods, which are applicable for the detection of hazardous substances such as explosives or drugs. Particular attention is focused on promising method of nuclear quadrupole resonance. Abroad this method has recently been applied in the detection of energetic materials in hazardous locations. The cornerstone of the nuclear quadrupole resonance is to evaluate the interaction between electromagnetic radiation, in the range of medium to very short waves, and the researched substance. Observed parameter are the resonant frequencies of the substance. Spectral analysis of signal is used for their evaluation. Resonant frequencies are always typical for the crystalline structure, therefore every explosive or drug is clearly identifiable by this method.
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Analytical methods applied for the evaluation of environmental contamination by uranium ore mining
Bílek, Jiří ; Holubová, Zuzana (referee) ; Čáslavský, Josef (advisor)
This thesis deals with the testing procedures used in monitoring of environmental contamination after uranium ore mining in the uranium mine in Dolní Rožínka. It deals with the determination of radioactive elements radium, uranium and radon. The methods used for the determination of radioactive elements in mine laboratory in Dolní Rožínka are described. The thesis also mentions other applicable methods for determination of uranium. The metods of determination of manganese, iron and other metallic elements are also summarized in brief.The values of concentrations of monitored analytes in selected locations are presented at the end of the thesis. These values, which were provided by laboratories in Dolní Rožínka, are valid for 2010.
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