National Repository of Grey Literature 181 records found  beginprevious108 - 117nextend  jump to record: Search took 0.02 seconds. 
Heavy metals contamination of selected Brno city localities
Debnárová, Andrea ; Adamec, Vladimír (referee) ; Doležalová Weissmannová, Helena (advisor)
This thesis is focused on the degree of soil contamination with heavy metals in urban area of Brno. Samples were collected in three periods from October 2009 to March 2010, to represent different seasons and their impact on the concentration of heavy metals in examined soil. Ten locations was chosen, each with different level of concentration, starting with busy traffic area where the concentration of means was high continuing to areas located around habitation or parks. As result four elements were determined in every sample: Cu, Cd, Hg and Pb. Presence of copper and lead were detected by flame atomic absortion spectroscopy (F-AAS) and, cadmium by the help of electrothermal atomic absortion spectroscopy (ET-AAS). For the determination of mercury was used advanced mercury analyzer (AMA).
Heavy metal contamination of selected Brno city localities
Šebková, Michaela ; Sommer, Lumír (referee) ; Dočekalová, Hana (advisor)
The aim of this work is to study the soil and plant contamination by heavy metals (lead, cadmium and mercury) in five selected places of Brno city. The sampling place Opuštěná represents the heavily polluted locality with high traffic density situated in the city centre. Sampling places Vídeňská and Podstránská belong to medium polluted localities, that are situated close to frequented roads. Relatively clean localities are represented by Musorgského and Šrámkova places, which are situated in peripheral city district with smaller traffic density. Soil and plants were sampled at two time periods (November 2008 and January 2009). Average amounts of mercury, cadmium and lead in collected soil samples are lower then limits of the Directive number 13/1994 of the Code of Ministry of the Environment. The content of heavy metals in soils corresponds to the sampling place. The highest value of metals content was found in the soil sampled at Opuštěná site. The content of lead and mercury in leaves of common dandelion was higher than the content in roots. In the case of cadmium the situation was opposite, the highest content was measured in underground part of the plant. It was found, that the content of heavy metals in leafy and underground part showed only small difference between sampling places. Nevertheless, the locality Opuštěná is found again as the highest contaminated place. Values of pH of collected soil samples were ranged in neutral area between 7 and 7,5.
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.
The presence of pollutants in matrices of bioindicators
Vlček, Ladislav ; Vávrová, Milada (referee) ; Doležalová Weissmannová, Helena (advisor)
This master‘s thesis concerns with occurrence of heavy metals in the environment, mainly in the matrices of bioindicators. Special attention is given to occurrence of mercury in the environment and its quantification in bioindicators. Mercury and its compounds are today considered as one of the most significant contaminants in the environment. Some sorts of mushrooms cumulate sizable amounts of mercury in their fruiting body and therefore we can use them to consider loading of different areas. Eight areas in Vizovice and its surroundings were chosen for these purposes and during the years 2006 – 2008 harvested 50 samples from 19 sorts of mushrooms from there. The concentrations of Hg were determined in all samples by single-purpose absorption spectrometer AMA 254. Comparison of the mercury content between individual sorts of mushrooms in the same area as well as comparison of loading of areas was performed and also bioaccumulation ability of individual sorts of mushrooms was determined.
Analysis of alkyl-derivatives of mercury at biotic matrixes.
Tuhovčáková, Lenka ; Vávrová, Milada (referee) ; Doležalová Weissmannová, Helena (advisor)
At diploma thesis will be used for determination of alkyl - derivatives of mercury especially gass chromatography. At diploma thesis will be developed metod for it´s identification, quantification, standard operating procedure and validation of the method of determination of alkyl - derivatives of mercury in animal tissues. There will be evaluated level of contamination by the polutants.
Mercury in waste water
Paříková, Lucie ; Čelechovská, Olga (referee) ; Dočekalová, Hana (advisor)
In the time period from November to April of the academic year 2007/2008 presence of mercury and its forms was monitored in the waste waters of Faculty of Chemistry, VUT in Brno. The level of mercury was determined as total mercury with help of the atomic absorption spectrometry method and in available forms by diffusive gradient in thin film technique.
Testing of modified Iontosorb resins for its use in diffusive gradient in thin films technique
Szkandera, Roman ; Řezáčová, Veronika (referee) ; Diviš, Pavel (advisor)
6-mercaptopurine was joined by diazotation and copulation reactions on Iontosorb AV. Presence of thiol groups in modified resin was showed by infrared spectrometry. Amount of thiol groups was determined by iodometric titration. Resin gel was preparated from modified resin and agarose and both of them were tested for mercury determination by DGT technique.
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.
Pollutants in laboratory waste waters
Červenka, Jiří ; Zmrzlý, Martin (referee) ; Sponar, Jan (advisor)
Mercury is a very consequential pollutant. It´s contained in all components of environment. Analysis of mercury is very demanding. Since mercury is ranked among dangerous chemicals, its quantity is limited and checked not only in environment. The aim of this thesis was to determine concentration of mercury in water from labs and in influent and effluent water from neutralization station of Brno university of Technology, Faculty of Chemistry. Water from neutralization is also mixed with sewage. Advanced mercury spectrometer AMA 254 was used or analysis. Results confirmed, that water flows out from lab to neutralization with relatively high concentration of mercury, highly exceeding limits of drainline. Water from neutralizing station also doesn´t show so high concentration of mercury, because it is mixed with waters from other labs and pH of water is amended. Special waste bottles for liquid waste with risk elements and dangerous compounds are available; from results can be decided, that not everybody follows the rules and some people might pour the waste right in to the sink. Resolution could have been safer acquisitions in labs. Students, who manipulate with dangerous chemicals should be alive to risk, which threatens with pouring into the sink, contamination and dangerous for all components of environment.
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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