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Extraction Detoxification of Sensitive Components
Andrle, Marek ; Vávrová, Milada (referee) ; Mika, Otakar Jiří (referee) ; Skoumal, Miroslav (referee) ; Čáslavský, Josef (advisor)
Solvent extraction is one of the methods available for the decontamination of sensitive equipments that are contaminated with chemical warfare agents. The efficiency of extraction method have been verified on the samples, (steel or rubber) that have been contaminated with drops of mustard gas. These samples have been inserted into the extraction flow cell through which solvent (ethoxynonafluorobutane - HFE-7200) flowed. The solvent was sampled in the time intervals. These samples of solvent were analysed for the concentration of mustard gas. Process of extraction was monitored for the three operational factors (the solvent flow rate, temperature and the ultrasound power) and for three different situations (dissolution of drops of mustard gas, mustard gas desorption from the structure of the sample and dissolve drops of mustard gas with the subsequent desorption from the sample). The development of the decontamination process in time was found to consist of two stages. In the first stage the rapid dissolution of the liquid part of mustard gas in a solvent and in the second phase was such as mustard desorption from the structure of the sample and this phase was considerably slower. Extraction is to accelerate increasing the value of the flow of the solvent, the temperature and the performance of the ultrasound. These operational fac-tors have a significant impact on the thickness of the laminar layer of solvent, the solvent replacement coefficient in a cell, diffusion parameters in the process, the viscosity, the solubility of mustard gas in a solvent and the maximum achievable concentration of mustard gas in the rubber sample. The values of adjustable parameters was obtained by mathematical analysis of mathematical model. The progress of extraction under different operational conditions can be predicted by these parameters. The effect of solvents and ultrasound was experimentally verified for selected equipments of computing and communication technology. The possibility of separation of chemical warfare agents from the solvent was verified too.
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Determination of organic tin compounds in the environment
Fojt, Jakub ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
Organotin compounds are one of the most produced and most used organometallic compounds. Some of these substances are endocrine disruptors, persistent organic polutants and their high toxic effects are observed. That’s why their presence in the environment caused by human activity could endanger many organisms. The aim of this thesis is summarize their properties and their occurrence in the environment. Then the quick, easy and relatively cheap method for determination of trialkyltin compounds in heavily poluted aquatic sediments using capillary zone electrophoresis is developed.
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Utilization of Diffusive Techniques in Study on Reactivity of Biocolloids
Kalina, Michal ; Maršálek, Roman (referee) ; Mráček, Aleš (referee) ; Klučáková, Martina (advisor)
The main aim of this thesis is the utilization of simple diffusion techniques for the study on transport properties of copper ions in the systems containing humic acids with respect to the other parameters, which can affect the process (the structure of diffusion environment, the interactions between transported specie and diffusion matrices, selective blocking of binding sites of humic acids). The first part of experimental works was focused on characterization of studied materials (humic acids, humic sol and humic hydrogel). The main part of the thesis was dealing with the optimization of simple diffusion techniques, which were suitable for the study on transport of copper ions in matrices containing humic acids, taking into account the mutual interactions between studied components in the system. The obtained diffusion characteristics were compared to the data determined using sorption experiments. Consequently, the minor goal of the experimental works of this thesis was also the assessment of the influence of basic physico-chemical parameters of studied materials on transport phenomenon.
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Determination of heavy metals in waste energetic materials with using sequential extraction
Kořínková, Alena ; Sommer, Lumír (referee) ; Doležalová Weissmannová, Helena (advisor)
Tato diplomová práce pojednává o stanovení vybraných kovů v energetických odpadech, jako je úletový popílek, škvára, struska, ložový popel, produkt odsíření apod., které pocházejí ze čtyř moravských tepláren. Extrakce kovů z energetických materiálů byla provedena Tessierovou extrakcí. Za tímto účelem byla použita extrakční činidla chlorid hořečnatý (MgCl2), octan sodný (CH3COONa), hydroxylamin hydrochlorid v kyselině octové (NH2OH.HCl v CH3COOH), peroxid vodíku v kyselině dusičné (H2O2 v HNO3) a kyselina fluorovodíková (HF). Extrakce probíhala při teplotách 25°C a 40°C. Ve všech frakcích byly stanoveny olovo, měď a kadmium s využitím atomové absorpční spektrometrie (F AAS, ET AAS) a rtuť metodou AMA 254.
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Determination of ergosterol content in brewing materials
Matyáš, Martin ; Ing.Pavla Kožušníková, Ph.D. (referee) ; Benešová, Karolína (advisor)
Presented bachelor’s thesis is focused on determination of ergosterol content in barley and malt. In theoretical part the presence of ergosterol in barley and malt has been elaborated, the purposes of its determination, detailed overview of previously applied methods of extraction from samples of barley and malt as well as other biological materials and methods of quantification. Practical part is focused on optimizing of extraction and determination of ergosterol by high performance liquid chromatography with diode array detection (HPLC – DAD).
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Alkylderivatives of polycyclic aromatic hydrocarbons in the environment
Jagošová, Klára ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
This bachelor thesis deals with alkylderivatives of polycyclic aromatic hydrocarbons in the environment. Basic information about its physicochemical properties, toxicology and environmental fate is presented here. The second part of thesis is focused on suitable method for the determination of these harmful compounds, including sampling, extraction, cleaning step and final analysis. In the third part the draft of standard operating procedure for the determination of A-PAHs in the real sample is outlined. The analysis consists from three steps – Pressurized Solvent Extracttion, column chromatography and two dimensional gas chromatography with mass spectrometry. The final sections of thesis discusses the experimental part and results of determination of A-PAHs.
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Methods for the extraction of selected toxins from solid matrices and their subsequent determination by HPLC/MS
Herman, David ; Zlámalová Gargošová, Helena (referee) ; Čáslavský, Josef (advisor)
This diploma thesis is focused on the analysis of toxins and their extraction from sandyloamy soil. Particularly, saxitoxin and trichothecene mycotoxins deoxynivalenol, HT-2 and T-2 toxins are in the centre of interest of this work. Their occurrence, toxic properties and influence on living organisms are described in theoretical part of this thesis. In next chapters, currently published extraction methods for individual toxins and analytical approaches for their quantitative evaluation are summarized. In experimental part of this thesis, optimized process of sample pretreatment based on extraction of toxins from soil using 1mM HCOONH4 in 84% acetonitrile was proposed as the best option. Simultaneous determination of toxins was performed by liquid chromatography on a CN column (3.0 x 150 mm, 3 m, 100 ) in gradient elution mode. Mass spectrometer with electrospray as ion source and linear ion trap as analyzer was used as detector. Recovery of designed method was over 80% for trichothecene mycotoxins and 51% for saxitoxin.
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Evaluation of Fingerprint Morphing Methods Compared to a Real System
Kolínek, Daniel ; Kanich, Ondřej (referee) ; Drahanský, Martin (advisor)
The aim of this work is to design methods of fingerprint morphing, subsequently to implement the proposed methods and to test their effectiveness by breaking into real verification systems made by Innovatrics and Neurotechnology, two prominent companies in biometrics. Methods for morphing were designed mainly based on the article On the Feasibility of Creating Double-Identity Fingerprints where the part of the preparation of fingerprints on the input was modified and an adjustment of the output was made so that it is able to work with fingerprint images taken under different conditions. Fingerprints created by morphing were recognized as genuine in 41.72 % of cases when compared to the default threshold. The main benefit of this work is the created application for generating fingerprints using morphing and to point out that this method is a\,threat to existing systems used for fingerprint recognition.
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Possibility of further use of elderberry marc
Sedláčková, Lucie ; Pořízka, Jaromír (referee) ; Vespalcová, Milena (advisor)
This Diploma thesis talks about the production of concentrates and lyophilisate from the extract of elderberry moldlings (elderberry, Sambuvus nigra L.) and by determination by chosen chemical characteristics of these products. The theoretical part includes the botanical characteristics of the plant species Sambucus nigra L. Next is the part that is dedicated to biologicaly active substances found in elderberry and it‘s possible usage in the food industry. Next is the part where the extraction, purification and indentification of anthocyanic dyes are described. In the next part is the analyrical method HPLC described, including the description of instrumentation. The last part talks about the description of the used methods: methods for the concentration of the extract, UV-VIS spectrophotometry, determination of phenolic compounds, determination of dry matter, determination of active acidity and the overall titrating acidity. The experimental part contained the optimalization of the process of producing the extract from elderberry moldings. The extract obtained was then concentrated for preservation and characterization purposes based on selected chemical properties. The total content of anthocyanin dyes was chosen as a quality parameter. The most suitable process for the preparation of the extract was chosen to be the ratio of moldings and solvent 1:2, 4 (m/V). The most suitable solvent was chosen to be a mixture of water and ethanol in a ratio of 1:1 (V/V). According to the needs of the submitter, an extract with the use of water as the extraction agent is also provided. The prepared extract was then concentrated on a vacuum evaporator or lyophilized for storage purposes. The dye degradation while using the evaporator was the lowest in a 40 ° C water bath. The final products were characterized by the determination of soluble solids, pH, titration acidity, total phenolic compounds and total anthocyanin dyes. The anthocyanin pigments contained identified by liquid chromatography are: cyanidine-3-sambubioside, cyanidine-3-glucoside, cyanidine-3-sambubioside-5-glucoside, and cyanidine-3,5-diglucoside The total content of anthocyanins in the concentrate was determined to be equivalent to cyanidine-3-glucoside at 2.8 gl-1 and in the lyophilisate 2.5 gl-1.
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Substituted polyaromatic compounds in environmental components
Kubalík, David ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
This work is focused on substituted polycyclic aromatic hydrocarbons (PAHs) in environmental compartments. The thesis examined the development of these compounds and their entry into the ecosystem. Due to their proven negative characteristics to be addressed also their toxicology. The next section discusses the appropriate methods, including sampling, sample preparation and final determination. The conclusion of this work forms draft standard operating procedure for their determination.
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