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Development of Gel Techniques for in situ Measurement of Bioavailable Metals in Soils and Sediments
Kovaříková, Vladěna ; Sommer, Lumír (referee) ; Janoš, Pavel (referee) ; Dočekalová, Hana (advisor)
The doctoral thesis deals with usage of gel techniques for in situ measurement of bioavailable metals in soils and sediments. The DGT technique was applied to soil samples from the localities of Zlín, Tuřany and Chrlice for estimation of bioavailable metals in soils. These soils were amended by sewage sludges in years 1980-1987. The experiment using diffusive gels with different pore size, APA and RG gels, has shown that the DGT can be used for assessment of trace metal soil complexes - small inorganic and larger organic. The results obtained by DGT measurements were approximately up to two orders of magnitude lower than metal concentrations obtained by leaching with sodium nitrate. The leaching with sodium nitrate does not provide true reflection of metal availability to plant root system and soil microorganisms and the DGT technique seems to be a better predictor of metal bioavailability. Only small differences between undisturbed and homogenized soil samples were found out by application of DGT to soil samples from localities of Veverská Bítýška and Ostrovačice. The undisturbed soil is not homogenous and the DGT unit gives information only about the part of the soil which is in direct contact with the unit. The procedure with soil slurry can be recommended for the characterization of large soil areas and estimation of bioavailable metals in soils. Gel techniques were also used for the study of processes occuring in sediments. Mercury species and other metals were analysed in surface water, pore water and sediments collected from two sampling sites in the Dele River in northern France. This river had been polluted during the last century by the activity of Métaleurop factory, which dealt with metal ore treatment. The application of DGT technique using two specific ion-exchange resins, Chelex-100 and Duolite GT-73, provided assessment of mercury in sediment pore water. DGT and DET techniques together with centrifugation provided also high resolution depth profiles of Fe, Mn, Zn, Pb, Cr and Cd in pore water. It is not possible to determine which sampling site was more contaminated. Only small differences in mercury species and metal content were observed between sampling sites. The Dele River can be classified as contaminated river according to total mercury content in sediments and as slightly contaminated river from the point of view of methylmercury content. Correlations between mercury species and sulphide content confirm that total mercury and sulphide content count among factors influencing the mercury release to pore water and controlling processes of methylation and demethylation. Only low toxicity of sediment slurries was found out by the bioluminiscence test with Vibrio fischeri. The results of doctoral thesis demonstrate gel techniques as a very good tool in environmental analysis.
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Removal of lead and other metals from water
Šopíková, Lucie ; Vybíralová, Pavla (referee) ; Biela, Renata (advisor)
This work covers the topic of metals and semimetals in water. It is divided into three parts. First, each element is characterized by its properties and behavior in water. Incidence in the environment, utilization and effects of intake on human body are described for each element. Second, means of elimination from water are introduced. Different chemical, mechanical and biological methods are discussed. In greater detail, precipitate method, cementation, electrochemical processes, sorption and biosorption are reviewed. Third, hands-on filtration experiment of polluted water with the help of different filtration materials is included. This experiment was done in a laboratory belonging to the Institute of Municipal Water Management, Faculty of Civil Engineering, Brno University of Technology.
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Removal of selected metals from the water
Pěkný, Mojmír ; Vybíralová, Pavla (referee) ; Biela, Renata (advisor)
In my thesis I focused on the problem of removal of some heavy metals from water. Heavy metals cause deterioration of quality of water sources and bring about a need of complicated water treatment technologies. In particular it is the case of mercury, arsenic, cadmium, lead, chromium and nickel. This diploma thesis focuses on the utilization of adsorption using suitable adsorption materials to reduce concentrations of nickel in drinking water. At the same time it investigates the effectiveness of these materials in the process of removing iron and manganese from water. The first part of my thesis presents an overview of these metals. I write about their occurrence, its forms, properties and significance. The second part of the work focuses on the laboratory observations of the effectiveness in removing iron, manganese and nickel from water. The description of the used sorptive materials is also included.
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Determination of selected metals in fruit compotes
Hauerlandová, Petra ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This diploma thesis deals with the determination of some metals in fruit compotes packed in cans. There is described the production of fruit compotes and metal packaging legislation relating to the studied issues, the possibility of contamination of food packaging components, packaging corrosion, metal migration from packaging and techniques used for the analysis of metals in the food industry. Concentrations of metals in 14 different fruit compotes from a commercial network in the Czech Republic were determined by ICP-MS technique in the experimental part. Concentrations of metals were detected only in the juice of stewed fruit, because the juice is in direct contact with the surface of packaging, and metals are transferred first into it. The measured values were compared with the maximum permissible levels of metals in fruit compote determined by European legislation. In some cases there were found higher concentrations of tin, but other metals did not exceed the allowable amounts. Concentrations of metals in the compote varied depending on the kind of compote, which could be due to a different chemical composition of compotes depending on the origin of food and process of the fruit production, or a different cans coating material.
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Determination of alergenic and potential alergenic metals in cosmetics
Krakovková, Lenka ; Zemanová, Jana (referee) ; Diviš, Pavel (advisor)
The aim of the diploma thesis was to provide an overview of the prevalence of allergenic and potentially allergenic metals in eye shadows. The diploma thesis gives an overview of the legislation on cosmetics and description of the types of allergenic reactions caused by allergenic and potential allergenic metals in eye shadows. Listed below are the preparation methods of the samples for analysis and the list of the methods by which can the selected metals be analyzed. The experimental part of the diploma thesis deals with an analysis of selected allergenic and potentially allergenic metals in eye shadows. In the experimental part of diploma thesis method of sample preparation for analysis of eye shadows and a method of analysis of sample of eye shadows by ICP-MS have been optimized. Monitored analytes were selected metals. Altogether 6 samples of eye shadows from different manufacturers were chosen. Measured results have been statistically processed, confronted with the applicable legislation and assessed in terms of possible allergic reactions.
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Overview of rapid prototyping technology for metallic parts
Žaba, Tomáš ; Nevrlý, Josef (referee) ; Paloušek, David (advisor)
The aim of this bachelor paper is to make a survey of Rapid Prototyping methods which enable workability of metal materials. It explains the principles of older methods as well as the latest ones including Selective Laser Sintering, Direct Metal Laser Sintering, and Laser Engineered Net Shaping, Direct Metal Deposition and Electron Beam Melting. The paper presents the examples of practical applications on component parts. The latest equipment and machinery available on present market and their technical specification are listed at the end of the description of individual methods. The paper is completed with visual documentation. The final part of the paper contains the analysis of gained pieces of knowledge and future possible development is outlined.
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