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Chemical composition of photovoltaic panels
Koudelová, Marta ; Šebek, Ondřej (advisor) ; Tejnecký, Václav (referee)
The bachelor's thesis is focused on the issue of photovoltaic cells and panels. The literature search was formed from selected available literature with the purpose to characterize different types of the crystalline silicon photovoltaic cells and thin-films photovoltaic cells and describe the application of photovoltaic cells in the world and in the Czech Republic. In the next part of this thesis is a summary of current knowledge about recycling of photovoltaic cells and other utilization of layers and their possible impact on the environment. The practical part of the thesis deals with selected samples of PV panels. A few samples of photovoltaic panels were taken for chemical analyses. Chemical analyses are performed of the five samples of the photovoltaic panels. The results of chemical analyses were compared with acquired data from the literature. The results of the multielementary analysis of selected samples was that the photovoltaic panels contain a risk elements (e. g. As, Cd, Sb, Mo). The PV panels also contain economics utilizable elements (Ag). Content of silicon is up to 78,18 % SiO2. Key words Photovoltaic panel, photovoltaic cell, chemical analysis, risk elements, recycling
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The study of PET bottles in terms of the content of risk elements
Kryštofová, Petra ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of PET bottles in terms of the possible content of risk elements. The contents of antimony, copper and lead were determined in the PET packaging material and in the beverages contained in the bottles. A total of 15 samples of bottled still and infant water available in the Czech sales network were analyzed. The PET material was decomposed in an acidic medium under the action of microwave radiation under optimized conditions. Atomic absorption spectrometric methods with flame or graphite cuvette atomization were used to determine selected risk elements based on the predicted analyte concentrations. In the PET packaging material, 159.35 to 265.68 mgkg-1 of antimony were determined, the determined values of lead concentration were in the range of 10.96-20.23 mg·kg-1 and the copper concentration in the range of 0.11-7,52 mg·kg-1. In bottled water and in bottled infant water, antimony was identified only in samples labeled 6a, 8a, 9a and 15a, all lead concentrations were measured below LODPb, copper was determined only in samples 2a, 6a and 8a. In none of the samples did the concentrations given by the valid legislation be exceeded. The limits of these metals are not set in legislation in the packaging materials, only specific migration limits and they have not been exceeded. However, the high concentration of antimony in PET poses a potential risk of contamination of the contents of these packages.
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Geologická a geobiocenologická charakteristika vybraných lomů na Kutnohorsku
Votlučka, Martin
The thesis Geobiocenologické geological characteristics of selected quarries the Kutná Hora, is related to the antropogenic montainery landscape unites and theeir wider sur-roundings with a special focus on soil environment, tree evolution and succession and their ecophysiology affected by their habitat, environment, soil and bedrock geochem-istry. The thesis describes the geological phenomens and history if mining and uses of select-ed quarries Vlastějovice, Bernartice, Malešova and their surroundings in relation to the studied localities. Furthermore, quarries of Vlastějovice and Bernartice are currently still in operation. The author gives an overview of a number of characteristics of the territory. In the practical part are compared pedological conditions in quarries, with regard to the diversity of soils and their chemical composition in relation to bedrock. Greater emphasis is placed on influencing tree evolution and their ecophysiology in relation to soil, parental bedrock and distribution of elements contained in different soil horizons and trees. Comparison is based on the author's own field investigations and laboratory analyzes of soil chemistry conquered by XRF spectrometry analysis, as well as soil physics and influence to trees by all these mentioned factors. The paper also describes botanical and climatic characteristics of all quarries, forest typology and phytocenology in quarries and surrounding regions. The results are briefly discussed in chapter discussion and results of thesis are ilustrated by graphs, photographs and tables placed in the Annexes to this thesis.
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Geochemická charakteristika půdního prostředí se zaměřením na kontaminaci lesních půd podél vybraných silničních komunikací
Petr, Jan
There was investigation of elemental composition through XRF analysis. Seventeen samples were collected from around Vír and Brno dam. Samples were taken from sites with emphasis on the difference in traffic density. After analyzing the samples three of the eleven risk elements were found, including arsenic (As), lead (Pb) and zinc (Zn). Contamination level was compared with limits given by Czech Ministry of the Environment. Two samples showed increased limits in contamination, arsenic (As) and zinc (Zn). However, after statistical investigation there was not discovered a link between traffic volume and increased concentration of risk elements in the soil.
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Exogenic alteration of geomaterials with anomalous content of hazardous elements
Udatný, Martin ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee) ; Vaněk, Aleš (referee)
of dissertation thesis Exogenic alteration of geomaterials with anomalous content of hazardous elements The research of waste materials from high temperature processes belongs to current issues solved in the field of modern environmental geochemistry. Current research has mainly been focused on fly ash and bottom ash coming from metallurgy, combustion and other industrial processes. In these wastes of different grain size, accumulation of hazardous elements occurs. These elements may be present in low concentrations in combusted coal or municipal solid waste or it may come from ore processing. Hazardous compounds are also intentionally added during the technological process (e.g. making of lead glass). Modern industrial plants are equipped with effective filtration systems, but this might not be in the past. In the Czech Republic and elsewhere in the world old environmental burdens are and will be addressed. Current modern filtration systems are never 100% efficient. Contamination of surrounding environment in a lesser extent can still occur. The production of lead glass (Bohemian Crystal) is based on the addition of lead compounds in the glass raw material. Additions of these substances providing a high refractive index of the finished product. Also compounds containing other hazardous elements...
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Methodical practice of taking samples fertilizers, plants and soil for determination of risk elements in agro-ecosystems and other parameters of soil fertility: applied methodology with certification
Kunzová, Eva ; Menšík, Ladislav ; Hejcman, Michal ; Dostál, Jiří
The methodology is describing latest findings on methods of sampling of barnyard manure, organic and organomineral fertilizers, samplings of vegetable material and soil for determination of risk elements content. As a part of the methodology there is description of laboratory methods for determination of dry matter content, pH, content of essential nutrients and risk elements in samples (of farmyard manure, organic and organomineral fertilizers, vegetable material and soil). Methodology is describing methods of characterization of quality of soil organic matter (SOM) and most important limit valuables of risk elements in fertilisers, substrates and soils. The application of methodology will be in the corporation farming on arable soil, grassland, classical and also ecological agriculture. It will be used also by accredited laboratories, agricultural consultant and in advisory framework of Ministry of Agriculture of Czech Republic etc. Methodology can be used by civil servants, students and teachers in secondary schools and agricultural universities etc.
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Chemical composition of photovoltaic panels
Koudelová, Marta ; Šebek, Ondřej (advisor) ; Tejnecký, Václav (referee)
The bachelor's thesis is focused on the issue of photovoltaic cells and panels. The literature search was formed from selected available literature with the purpose to characterize different types of the crystalline silicon photovoltaic cells and thin-films photovoltaic cells and describe the application of photovoltaic cells in the world and in the Czech Republic. In the next part of this thesis is a summary of current knowledge about recycling of photovoltaic cells and other utilization of layers and their possible impact on the environment. The practical part of the thesis deals with selected samples of PV panels. A few samples of photovoltaic panels were taken for chemical analyses. Chemical analyses are performed of the five samples of the photovoltaic panels. The results of chemical analyses were compared with acquired data from the literature. The results of the multielementary analysis of selected samples was that the photovoltaic panels contain a risk elements (e. g. As, Cd, Sb, Mo). The PV panels also contain economics utilizable elements (Ag). Content of silicon is up to 78,18 % SiO2. Key words Photovoltaic panel, photovoltaic cell, chemical analysis, risk elements, recycling
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Short and long term re-distribution of potentially toxic elements fractions in solid environmental samples
Jeřábková, Julie ; Drábek, Ondřej (advisor)
The fractionation of potentially toxic elements (PTE) in environmental and anthropogenic solid samples has a crucial influence on their leaching, mobility and bioavailability, or conversely, their immobilization. Redistribution of PTE in different fractions is affected by various soil properties, such as soil reaction, redox conditions, and soil organic matter composition and its content. Fractionation of PTE in soils and other environmental materials is therefore dynamic, as it is controlled by external conditions. Certain changes of soil conditions caused by, for example, climatic events (floods, soil washing, etc.) and human activities (eg. liming) may lead to significant changes in the distribution of fractions of PTE in soils and anthropogenic materials.
The aim of this study is to assess the impact of changes of conditions on the short- and long-term diferences in fractionation of selected PTE (As, Cd, Cr, Cu, Pb, Zn) in soils and other solid samples mainly of anthropogenic origin (e.g., smelter slag) in the environment.
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Risk elements contamination in Kutná Hora region and possibilities of its usage in paleoenvironmental research
Horák, Jan ; Hejcman, Michal (advisor) ; Jaromír, Jaromír (referee)
The dissertation focuses on topic of using risk elements contamination as a stratigraphic marker in palaeoenvironmental research. The contamination is not studied only as itself, but is viewed as a way to analyse and interpret the sedimentary record of historical events. The contamination carries the information about its original place, its original activity, about development of the landscape.
The Kutná Hora region (central Bohemia; 49°57'0.170"N, 15°15'59.877"E) is a region of important historic mining and smelting activity. The mining started in 13th century and lasted until half of 16th century. Then only sporadic attempts of renewal were made. Spatially limited mining was renewed in second half of the 20th century. Therefore, it is highly probable to find here the contaminants in the role of stratigraphic markers. In the research were used mainly As, Be, Cd, Co, Cr, Cu, Hg, Pb, V and Zn as these are the most analysed in contamination studies performed in the region.
The aims of the dissertation were to answer these questions:
To characterize the contamination
- Are some risk elements typical for the contamination originating from the mining and smelting?
- If so, is their environmental (spatial, sedimentary) manifestation diversified?
- Is possible diversity spatially related to particular landscape features or areas?
- Is possible diversity connected to particular activities?
To use the answers in analysis of particular sites
- Is it possible to use the risk elements contamination as stratigraphic marker in fluvial sediments?
- How is the interpretation of particular site influenced by the whole context of regional contamination?
The core of the research is the metaanalysis of contamination data coming from region (the data obtained by our research and also from other studies). The results have brought not only basic characteristics of contamination, mainly concentrations. The crucial result was the structure of studied elemental complex. Only As, Cd, Cu, Pb and Zn are connected to contamination originating in mining and smelting. Other elements - their concentrations and spatial distributions - are uninfluenced by mining and smelting activities. More, the information about connection of As and Cd to mining and Cu, Pb and Zn to smelting was revealed. Both groups recorded with different spatial distributions. Also comparison of results by different approaches has shown that some statistical processing (clr-transformation) of such dataset was much better for interpretation than analyses of only concentrations values.
We studied also the area of confluence of two rivers - Klejnárka (main river draining contaminated region), which is tributary to Labe (Elbe) river. The contamination is still recognizable here, but the diversity between contamination elements is not. The confluence of rivers strongly dilutes the contaminated material. The concentrations decrease. Also here clr-transformation of data enabled to analyse structures of contaminants spatial distribution unrecognizable by concentrations values.
We performed also two vertical profiles analyses. It was shown, that it is highly risky to interpret data of such origin without the complex information about regional contamination context. It was revealed by contextual interpretation of data from one of the profiles, that there is a mixing of geochemical data coming from different statistical populations. The contamination works there as only one of the factors influencing sedimentary record. The site is therefore suitable for statistical testing of two populations mixing, outliers` detection and the like.
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The effect of cadmium on oxidative stress in plants
Zemanová, Veronika ; Pavlíková, Daniela (advisor) ; Tomáš, Tomáš (referee)
The two ecotypes of Noccaea caerulescens originating from two differently contaminated sites (Redlschlag, Austria; Ganges, France), N. praecox (Mežica, Slovenia), Arabidopsis halleri and Spinacia oleracea were studied to compare Cd accumulation and tolerance. After 30, 60, 90 and 120 days of cultivation in Cd contaminated soil (30, 60 and 90 mg Cd/kg soil) for hyperaccumulators and 25, 40, 55 and 75 days of cultivation in Cd contaminated soil (30, 60 and 90 mg Cd/kg soil) for spinach gas-exchange parameters (net photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO2 concentration), fatty acids, macro- and microelements were determined as well as N utilization by plants. Noccaea species and A. halleri showed similar changes in yield of biomass, Cd content and total content of amino acids. These species confirmed differences in the profile and contents of individual free amino acids. The comparison between Noccaea species showed that Cd stress resulted in similar changes of gas-exchange parameters. Contrasting responses of plants to Cd contamination were confirmed in macro- and microelements contents, fatty acids and amino acids metabolism. Spinach showed contrasting response to cadmium compared to hyperaccumulators, especially in profile of free amino acids and fatty acids.
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