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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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Selected inorganic pollutants in foodstuffs
Kroupová, Kateřina ; Vítová, Eva (referee) ; Vitoulová, Eva (advisor)
This bachelor thesis is focus on occurrence of inorganic pollutants in foodstuffs. The introduction is dedicated to apperance of individual selected elements in foodstuffs. Concentration of these elements is very important factor for examination of toxic effects for the human organism. If we want to avoid the harmful effects to the human organism, we have to define border limits. Work is based on the legislative of Czech republic. Second part of this study is focused on the biological monitoring. The biological monitoring is important for precautionary measures. In the third part of this study are described toxical effects of these elements to the human organism. Before qualitative and quantitative analysis by instrumental techniques is important to properly take the sample. In the fourth and fifth part of this work are mentioned methods used for determination of these elements and metods of taking samples. This bachelor thesis provide complex view on the problems of pollutants in foodstuffs and it should be used as a base for following diploma thesis.
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Contamination of soil and sediment by hazardous metals
Pidima, Tomáš ; Komendová, Renata (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor thesis deals with soil and sediments from the environmental perspective. For selected heavy metals – cadmium, lead and mercury are given information about their occurrence, characteristics and potential sources of environmental contamination. It is also mentioned legislation dealing with the topic. The limit concentrations in soil and sediments, determination methodology and principles of the most commonly used instrumental analytical methods for these elements are described.
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The study of behavior of platinum nanoparticles in environmental compartments
Berka, Michal ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
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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Spectrophotometric determination of Chromium(III) with organic reagents
Nevrlá, Jana ; Komendová, Renata (referee) ; Sommer, Lumír (advisor)
The theoretical part of this master’s thesis is mainly focused on the physical and chemical properties of chromium, its toxicity and possibility of entering of various forms of chromium into the environment. There are also described the most common analytical methods for determination of chromium in water, including ways of modification and preconcentration water samples. The aim of experimental part is the optimalization and assessing the conditions spectrophotometric determination of Cr(III) by selected organic reagents (chromazurol S, eriochromcyanine R, 4-(2-thiazolylazo)resorcinol) and their comparison with the determination of total chromium, as Cr(III), using atomic absorption spectrometry with electrothermic atomization. The analytical procedure for spectrophotometric determination of chromium with chromazurol S, which was found to be most suitable and ET-AAS, were applied to real water samples.
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Determination of platinum in Brno's agglomeration
Dvořák, Rostislav ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This thesis is focused on the determination of platinum in samples of road dust and soil by atomic absorption spectrometry. The theoretical part describes the basic physical and chemical properties of platinum, platinum function in automotive converters and its behavior in the environment. In the experimental section summarizes the methods used to decompositions samples, concentration of the analyte and the main results of the measurements.
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The use of ion exchanges for preconcentration of platinum group metals
Sýkora, Jiří ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
The aim of this thesis is the elaboration of a detailed literature review on the use of ion exchangers for the preconcentration of platinum group metals. This work contains an actual literature review on this issue. In this work you will find information about the current occurrence of platinum metals in the environment, their impact on health, properties, resources and the use. There are also described ways of decomposition, extraction and use of ion exchangers. In the experimental part this thesis deals with optimization of ion exchangers and following application of real samples from the city of Brno.
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Generation of volatile zinc chelates from aqueous matrix
Kračmarová, Aneta ; Nováková, Eliška (advisor) ; Červený, Václav (referee)
The topic of this work was optimization of the conditions for the generation of volatile zinc chelates. The aim was to develop an alternative method for generating volatile Zn speciates to its reduction by sodium tetrahydridoborate. Detection was carried out by atomic absorption spectrometry. Optimization of the conditions of the chelation reaction itself included the selection of a suitable chelating agent and appropriate modifiers, pH adjustment, suitable reagent and carrier gas flow rates, and appropriate apparatus arrangement. The following method characteristics were obtained under optimal conditions: LOD 1.55 mg L-1 , LOQ 5.17 mg L-1 and sensitivity 0.245 s L mg-1 . The repeatability was 13,7 %. The addition of modifiers was then tested to increase the efficiency of generation of volatile zinc chelates. Potential modifiers included transition metals, organic solvents, heterocyclic organic compounds, compounds from the carbamate group and surfactants. The heterocyclic 1,10-phenanthroline and the carbamate NaPDC were included in the optimal conditions because without them it was not possible to distinguish the signal from noise. Acetonitrile proved to be the most effective modifier, increasing the efficiency to 1547 %. With the addition of acetonitrile, the LOD decreased to 0.191 mg L-1 , the...
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Analýza obsahu významných nutrientů v tropickém ovoci a v jejich škůdcích
Remencová, Julie
The diploma thesis is focused on analysis of selected elements of tropical fruits and their pests. The aim of the thesis was to find a relationship between mineral content of tropical fruits and their pests and to clarify whether the found correlations can be used for targeted pest management. The mediterranean fruit fly (Ceratitis capitata) and peach fruit fly (Bactrocera zonata) are one of the most dangerous and economically important species of Tephritidae family causing significant economical looses estimated in hundreds of millions of dollars per year. The theoretical part focuses on general description, production and consumption, chemical content and importance of individual analysed tropical fruit species. Literature review deals with selected elements – calcium, magnesium, iron, zinc, manganese and copper from the point of view of importance in human nutrition. The practical part describes analyses of the above mentioned elements using flame absorption spectrometry in samples of mango (Mangifera indica), mandarin (Citrus unshiu), kaki (Diospyros kaki) and pomegranate (Punica granatum) and samples of two fruit fly species C. capitata and B. zonata. From the correlations of elements contents in tropical fruits and their pests follows that the determination of calcium can be used for identification of the origin of the pest because a significant correlation was found only between the content of calcium in mandarin and C. capitata fed on mandarin.
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