National Repository of Grey Literature 108 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
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.
The study of vertical mobility of heavy metals and their transfer to mushrooms
Jurnečka, Roman ; Doležalová Weissmannová, Helena (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of contamination of forest soils and edible mushrooms with lead, cadmium, copper and zinc in the Jeseníky Mountains, specifically in the Domašov and Vápenná forests. Sampling took place at 12 localities, divided into spruce and beech stands. Atomic absorption spectrometry AAS ContrAA 800D was chosen to determine the content of selected heavy metals. Based on the measured values of the concentrations of the studied metals and other soil properties, dependences were created to determine the vertical mobility of selected metals in the soil profile. Vertical mobility depends on the physico-chemical properties of the soil (pH, C and S content). The dependence of the content of selected heavy metals in the soil on the pH value of the soil was found. In the case of lead, the sorption capacity of the soil organic component was confirmed. The risk and above-limit content of Pb, Cd and Cu was found on the yellow-boletus mushroom. Cadmium shows the highest bioavailability. Lead was evaluated as the element with the lowest mobility.
Study of road dust pollution using ICP mass spectrometry
Chalabala, Jan ; Komendová, Renata (referee) ; Vašinová Galiová, Michaela (advisor)
Nowadays, there are many studies focused on road dust as a matrix of interest because of its ability to accumulate contamination with contribution from road traffic. This master thesis is turned into study of road dust pollution from aglomeration of Ulaanbaatar, capital city of Mongolia. There are 113 samples devided on nine sets corresponding to major roads in Ulaanbaatar. Samples have been sieved on three size fractions and then decomposed by aqua regia. Middle size fraction 45–63 µm has been analyzed using ICP-MS mass spektrometry. For purposes of contamination assesment, analyzed elements have been devided into two groups: contaminants (Cr, Cu, Zn, Pb and As) and rare earth elements (REE). Measured contents for elements have been compared with values of geochemical backgroud. Firstly for each set of samples and secondly for each sampling point. For first group of elements (contaminants), antropogenic contamination have been found, especially in the centre of Ulaanbaatar. As a probable source of this contamination, road traffic for Cu, Zn and Pb and coal combustion for Pb a As, have been identified. For REE group hasn´t been found any antropogenic enrichment.
Issues of boron in water
Šípková, Helena ; Nevrlá, Jana (referee) ; Komendová, Renata (advisor)
This bachelor thesis is focused on boron and its compounds. It is dedicated to properties, sources and the use of these substances and their effects on living organisms. The emphasis is put on the issue of boron in water. In this work are possible forms of this element in water, legislative rules and regulations and methods of its determination described. The experimental part is focused on azomethine-H spectrophotometric analysis to identify the stability of boron samples and their possible preservation.
Classification of material used for the construction of garden ponds
Sýkora, Jiří ; Repková, Martina (referee) ; Komendová, Renata (advisor)
This thesis deals with the study of the occurrence forms of inorganic phosphorus in water garden ponds and used material impact on the amount of releasable amount of phosphorus in the form of phosphates in the water medium. The practical part of this work focuses on the analysis and subsequent classification of building materials for the production of garden ponds just by releasing ability of phosphorus in the form of phosphates in the water.
Monitoring of water and sediments contamination after uranium ore mining
Kurfürst, Vlastimil ; Komendová, Renata (referee) ; Čáslavský, Josef (advisor)
This paper deals with the monitoring of water contamination and sediments in the area of Olší - Drahonín. Firstly, the water contamination released into the river Hadůvka is evaluated. Secondly, the sediments in the river are monitored and the surface water flow is evaluated. Finally, the water treatment technology and sampling is described. A description of the separation methods and choice of standard methods is outlined.
Nanoparticles of platinum metals in the environment
Berka, Michal ; Kučerík, Jiří (referee) ; Komendová, Renata (advisor)
Platinum nanoparticles, mainly released from automotive catalysts, pose a potential risk to the environment. The aim of this bachelor thesis is to investigate the effect of platinum nanoparticles on soil properties at different humidities. Specifically, how nanoparticles affect the stability of hydrogen bridges, the stability of aliphatic crystals, and water retention in soil. For the analysis of relations between platinum nanoparticles, water and soil, a method of thermal analysis was used, namely differential scanning calorimetry. The theoretical part is devoted to the general introduction to platinum metals and nanoparticles. And the preparation of nanoparticles, their characterization and their properties. The result of the experiments is that platinum nanoparticles affect the soil properties relatively significantly.
Use of biomarkers for assessing environmental pollution by platinum group metals
Nedvědická, Lucie ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This diploma thesis in the theoretical part analyses the characteristic feature of individual platinum group elements, their toxicity, anthropogenic sources and the presence of platinum group elements in the environment of the Czech Republic. In addition, there are specified types of bioindicators focusing mainly on lichens, mosses and needles. There are described individual bioindication techniques and pre-treatment of samples for platinum metals determination in bioindicators. The subject of the experimental part is to verify the sorption efficiency and ability of platinum and palladium using the SPE method and to determine the actual platinum metal contamination in selected localities in the city of Brno. There was also the additionally subject to verify the sorption potential of selected bioindicators and determination of the environmental pollution by platinum metals using the bag technique. In the experimental part, the bioindicators of moss Pleurozium schreberi, lichen Xanthoria parietina, lichen Flavoparmelia caperata and needles Pinus nigra were used.
Application of mosses and lichnes for the evaluation of presence of the metals in the environment
Pavlovičová, Adriána ; Vávrová, Milada (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the use of mosses and lichens as plant bioindicators, to assess environmental pollution by metals. Defines the sources of metals in the environment, describes the morphology of species of mosses and lichens. The last part refers to methods of active biomonitoring which use mosses and lichens and proposes concrete species of mosses and lichens, which could be used to assess environmental platinum metal pollution.
Methods of water samples processing with subsequent in vitro detection of endocrine disrupters
Daniel, Romain Oliver ; Komendová, Renata (referee) ; Bittner,, Michal (advisor)
In recent years, interest in monitoring of estrogenic compounds in water environment due to their adverse effects on human and animal health has been increased. Partiucular attention is paid to analytical techniques used to quantify estrogens in water samples, such as instrumental and biological techniques (in vitro, in vivo). Water samples need to be concentrated due to very low estrogen levels (ng·L-1) and low limit of detection of used analytical methods. Solid phase extraction (SPE) or liquid-liquid extraction (LLE) are comonly used to concentrate water samples. This bachelor thesis represents reverse osmosis (RO) and nanofiltration (NF) as another possible methods for this purpose. This thesis is focused on the preconcentration of water samples spiked with four estrogens (estrone E1, 17-estradiol E2, estriol E3 and 17-ethynylestradiol EE2) and surface water samples taken from three watercourses in city of Brno using RO and SPE and its comparison of their effeciency. This was evaluated by in vitro estrogenicity assay on the stably transfected cell line hER-HeLa-9903. By using RO, estrogens were concentrated with different recovery – the highest recovery was reached for EE2 129.29%, lowest for E2 38.53%. No detectable amount of estrogen has been detected in surface water samples. RO appears to be a suitable method to the water samples preconcentration prior to in vitro analysis of endocrine disrupting compounds. Water samples treated by the SPE method were not measured untill the sunbmission of bachelor thesis, so the RO and SPE efficiency was not performed.

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4 Komendová, Radka
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