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Microdetermination of cobalt by methods of molecular and atomic absorption spectrometry
Charuza, Martin ; Řezáčová, Veronika (referee) ; Sommer, Lumír (advisor)
This diploma thesis is focused on microdetermination of cobalt by UV-VIS spectrophotometry with organic agents and comparison with atomic absorption spectrometry. In the first part properties, occurance and importance of cobalt in the environment are desribed, complete with as a part of vitamine B12. Attention is also given to cobalt compounds, especially in the oxidative states +II and +III. Methods of preconcentration and preparation cobalt determination in real samples are adduced. In this thesis are described some optical analytical methods with accept on spectrophotometric agents for determination of cobalt. The experimental part of this thesis icludes optimalization of the spectrophotometric determination of cobalt with choosen organic agents 4-(2-pyridylazo)resorcin and 2-(5-Brom-2-pyridylazo)-5-diethylaminophenol and optimalization of atomic absorption spectrometry for cobalt determination. All of real samples of water (surface, underground, mineral and waste) were measured by both 4-(2-pyridylazo)resorcin and 2-(5-Brom-2-pyridylazo)-5-diethylaminophenol via UV-VIS and via atomic absorption spectrometry. Results of determinations were compared. A sample of vitamine B12 was measured too by all techniques.
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Phosphorus and its compounds in the environment
Lefnerová, Marcela ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor´s thesis deal with problems of phosphorus in waters, mainly in garden pond. This thesis analyse phosphorus attributes, forms of occurrence and negative effect in excessive occurrence. Next part is concentrate on common methods for remove phosphorus from water and methods of determination in waters and soils. For thesis on important mainly chapter about mobile analyse. Last part deals directly with bathing ecological ponds and Union of founding and maintenance of green. This part occupy with goals this union and introduction of control of materials, mainly from point of view of volume of phosphorus infuse to pond water.
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Characterization of the resin gels for mercury determination by DGT technique.
Finsterlová, Hana ; Řezáčová, Veronika (referee) ; Diviš, Pavel (advisor)
The aim of this thesis is testing of resin gels used in diffusive gradients in thin films technique (DGT) for determination of mercury in natural waters. The sorbets, chosen for preparation of resing gels were: Duolit GT- 73, Spheron- Thiol, and Chelex 100 and newly modified sorbent Iontosorb AV. At the beginning of work, the preparation procedure of all resing gels was optimized. After optimalization of preparation procedure the resin gels were tested in mercury model solutions. The recovery test and time dependence test were performed. When the basic tests were finished, they were followed by the tests of influence of natural ligand (humic acids and chlorides), and other parameters (above all pH and ionic strenght), on mercury determination by DGT technique.
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Modern herbs in the food industry
Adamczyková, Michaela ; Řezáčová, Veronika (referee) ; Vítová, Eva (advisor)
The bachelor thesis deals with the issue of volatile (aromatic) compounds of Plectranthus spp. and Echinacea purpurea. The theoretical part focuses on the general characteristics of the above mentioned herbs, the content of their bioactive and volatile compounds, and on their importance as well as on their potential use in the food industry. Using the HS-SPME-GC-MS method, the volatile compounds of the herbs and extracts prepared from them were identified and quantified in the experimental part. A total of 11 volatile compounds were found in all the samples. The most frequent one in the sample of a fresh Plectranthus was 3-carene (13,78%) as well as in the sample of dried Plectranthus (14,85%). However, in the Plectranthus extract it was -selinene (17,84%). As for Echinacea, it is germacrene D (18,64%) in the sample of a fresh one, camphor (58,46%) in the one of dried Echinacea and -copaene (20,42%) in its extract.
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Study of the availability of antibiotics in soil
Hroncová, Michala ; Landová, Pavlína (referee) ; Řezáčová, Veronika (advisor)
The diploma thesis is focused on the determination of tetracyclines, sulfonamides and fluoroquinolones from soil. Antibiotics such as tetracycline, chlortetracycline, oxytetracycline. ciprofloxacin, trimethoprim, sulfamethaxazole and sulfadiazin were selected due to frequent use in veterinary medicine. Due to the fact that the soil is a complex matrix and contains many components that can interfere with the detection signal of analytes, it was necessary to use the MAX column in the SPE method, which removes fulvic aned humic acid from analytes and the HLB column Final analysis of the analytes was performed by liquid chromatography with mass detesction (LC-MS). The method was also used for real soil samples, which were delivered from ÚKZUS.
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Study of the content of risk elements in soils and plant material
Vlčková, Renáta ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the study of the content of selected heavy metals (Zn, Ni, Fe, Mn) in soils and mushrooms. The flame atomic absorption spectrometry method was used to determine the heavy metal content. Fungi and soil samples were collected at 18 sites in the Jeseníky region. The concentrations of heavy metals in the mushrooms were in the range from 140–582 mg/kg Zn, 48–380 mg/kg Fe, 5–19 mg/kg Mn and 3–8 mg/kg Ni. Zinc had the highest concentration value in all mushroom species. In soils, the concentrations of heavy metals ranged from 10–72 g/kg Fe, 52–1,000 mg/kg Mn, 29–115 mg/kg Zn and 6–50 mg/kg Ni. Iron was the most abundant element in the soils. Mushrooms contamination was assessed as a health risk in the study area. However, the pollution of forest soils was assessed as satisfactory and thus the productive function of the soil is not impaired. The type of forest cover was found to have minimal effect on the chemical composition of the soils.
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Analysis of organic substances present in biochar
Bača, Ondřej ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This master's thesis deals with the analysis of organic substances, which are present in biochar. Biochar contains a number of organic compounds, that can be toxic and also carcinogenic to living organisms. In order for biochar to be used to improve soil quality or to be used for other applications, its safety must be declared by European or international certifications. Relevant European and international standards have been created for the determination of organic substances, that could be present in biochar. The theoretical part of the thesis was focused on selected organic substances, the process of pyrolysis and thermochemolysis, biochar characterisation and the used analytical methods. The experimental part of the thesis consisted of extraction with toluene and after that the determination of concentration of the 38 polycyclic aromatic hydrocarbons was performed. Qualitative analysis was performed by two-dimensional gas chromatography. Biochar samples were also subjected to thermochemolysis method and then they were analysed on GC-MS again. In both analytical methods, a large number of substances from groups such as PAHs, carboxylic acids, amines, substituted naphthalenes etc. was found, as well as smaller number of eg. polychlorinated biphenyls.
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Study of the interaction of selected pharmaceuticals with microplastics
Ioani, Aldina ; Řezáčová, Veronika (referee) ; Doležalová Weissmannová, Helena (advisor)
The bachelor thesis aims to study the interaction of selected pharmaceuticals from the group of analgesics and antibiotics with microplastics. The analysis was conducted in the mid-infrared region, which is used to identify chemical structure of the substances. Fourier transform infrared spectroscopy was used as an analytical method. The samples were subjected to technique attenuated total reflection. Ibuprofen and trimethoprim were chosen as analytes due to their common usage in the population. Sorption of pharmaceuticals was undergoing on polyhydroxybutyrate, which is a kind of biodegradable plastics and polyethene terephthalate, which is synthetic. Measured results showed that for the study of interaction with pharmaceuticals, it is more suitable to use biodegradable plastic polyhydroxybutyrate than polyethene terephthalate because of its better results. Infrared spectra output is very influenced by a selection of a solvent.
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Use of liquid chromatography to analyze caffeine solutions exposed to plasma
Brabcová, Kristýna ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This thesis deals with the current problem of increasing concentration of caffeine in water that is connected with caffeine consumption among people. This problem is not that urgent becusase the concentration is not high and for human is not so harmful. The bigger populaton is, the more caffeine people consume and the amount of caffeine in wastewater rises. This fact could be considered as a future problem. An appropriate method effective for elimination of harmful substances are advanced oxidation processes (AOP). Theoretical part describes purine alkaloids with detail desctription of caffeine. Plasma was chosen as a method for caffeine degradation and there are some facts described. There is a chapter about appropriate analytical methods. The samples were picked after periodical time intervals. These samples were analyzed by UHPLC. The results were compared with study dealing with this theme.
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Determination of volatile substances of natural extracts intended for cosmetic application
Paskevych, Olha ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Tato bakalářská práce je soustředěná na zkoumaní přírodních komerčně dostupných extraktů, které se používají do přírodní kosmetiky. Literární rešerše byla zaměřena na téma obsahu těkavých látek v přírodních extraktech používaných v kosmetice, jejich charakterizace a možnosti stanovení, problematika výskytu alergenů v přírodní kosmetice. Na základě tohoto přehledu byla navržena optimální metoda pro analýzu vzorků přírodních extraktů s přihlédnutím k dostupné analytické instrumentaci. Následující výtažky byly studovány se zaměřením na kvalitativní stanovení: mandle, aloe vera, hřebíček, Etiopská káva, zázvor, cibule.
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