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Analysis of substances potentially dangerous to humans found in lipsticks
Horáková, Kristýna ; Kučerová, Simona (referee) ; Diviš, Pavel (advisor)
The diploma thesis deals with the determination of the content of risk elements and parabens in lipsticks and the assessment of possible negative effects on human health associated with the use of lipsticks. Parabens were analyzed by high performance liquid chromatography with diode array detection (HPLC-DAD). Aluminum, cadmium and lead were analyzed on an inductively coupled plasma mass spectrometer (ICP-MS). The mercury content was determined using an atomic absorption spectrometer with an UV detector (AAS-UV). A total of 36 lipstick samples from 22 cosmetic brands were selected for analysis, with a savings price in the range of CZK 50–1500. Based on the measured metal concentrations, the hazard quotients (HQ) for individual metals as well as the total hazard index (HI) for the sum of all metals were calculated. Metal concentrations in lipsticks were further processed using Kruskall-Wallis Anova to divide samples according to price categories. The relationship between the content of individual metals and the purchase price has not been proven. Furthermore, a Kolmogór-Smirnov test was performed on these data to compare groups with vegan and not vegan composition. The content of aluminum, which was about 2.5 times lower in vegan cosmetics, proved to be statistically significant for this distribution. Parabens were detected in the minimum number of lipsticks examined, but in some cases information on the content of parabens was missing on the product packaging.
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Mercury emissions in energy industry
Hlavinková, Valérie ; Klimeš, Lubomír (referee) ; Charvát, Pavel (advisor)
This bachelor thesis deals with mercury emissions in the energy industry. The main sources are described and the combustion behavior of mercury is characterized. Legislative measures limit mercury emissions, which pollute the environment and endanger human health. The application method makes it possible to reduce these emissions.
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The study of contamination of forested areas of the Czech Republic by mercury
Trávníčková, Gabriela ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of mercury in the environment. It focuses on determining the concentration of total mercury in edible mushrooms and in the soil in 12 localities in the Jeseníky Mountains. A single-purpose absorption spectrometer AMA 254 was used to determine the mercury content. The sites where sampling took place were divided into 6 sites with spruce stand and 6 sites with beech stand. No relationship was found between the type of stand and the amount of accumulated mercury in the mushrooms. On a representative sample of yellow-boletus mushrooms found in each locality, it was found that the higher the amount of mercury in the mushroom, the lower the amount of mercury in the soil. The fungi are therefore able to accumulate mercury from the environment. Thus, they can become a potential source of intoxication when ingested. The mobility of heavy metals in the soils depends on many soil properties (pH, carbon and sulfur content). Metals form more soluble compounds in lower pH environments. The soil pH was very low and the lower the soil pH, the higher mercury concentration in the soil. This fact could be supported by acid fallout. The relationship between the mercury content and the carbon content of the soil confirmed that carbon has the ability to bind mercury. The higher the amount of carbon in the soil, the higher the amount of mercury.
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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).
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Fingerprinting and Identification of TLS Connections
Hejcman, Lukáš ; Kocnová, Jitka (referee) ; Kekely, Lukáš (advisor)
TLS je dnes nejpopulárnější šifrovací protokol používaný na internetu. Jeho cílem je poskytnout vysokou úroveň zabezpečení a soukromí pro komunikaci mezi zařízeními. Představuje však výzvu z hlediska monitorování a správy sítí, protože není možné analyzovat komunikaci šifrovanou pomocí tohoto protokolu ve velkém měřítku, pomocí existujících metod založených na detailní analýze obsahu paketů. Analýza šifrované komunikace může správcům pomoci detekovat škodlivou aktivitu v jejich sítích a také jim může pomoci identifikovat potenciální bezpečnostní hrozby. V této práci představuji metodu, která nám umožňuje využít výhod dvou metod otisků TLS, JA3 a Cisco Mercury, k určení operačního systému a procesů klientů v počítačové síti. Navržená metoda je schopna dosáhnout srovnatelných nebo lepších výsledků v porovnání se stávajícím přístupem Cisco Mercury pro vybrané datové sady a zároveň poskytuje možnosti pro detailnější analýzy klasifikací než JA3. V rámci práce je dále implementován modul pro systém NEMEA, který je schopný analyzovat TLS provoz pomocí nově navrženého přístupu.
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Assessment of soils and sediments contamination by heavy metals in the region Jihlava river
Marek, Milan ; Adamec, Vladimír (referee) ; Doležalová Weissmannová, Helena (advisor)
This diploma thesis deals with a potential contamination of hazardous metals of soil and sediments. The metals cadmium, copper, lead and mercury were chosen, their specification, limited concentration and methods of determination are also described in thesis. City Jihlava and its surroundings were chosen for evaluating pollution of the soil and sediments in this area. In collected samples of the soil and sediments presence of copper, cadmium, lead and mercury were detected via atomic absorption spectrometry (F-AAS, ET-AAS, AMA 254). The metal pollution of soils and sediments by hazardous elements in Jihlava River and in Jihlava region was evaluated.
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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.
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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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Cycling of mercury and mercury species in the environment
Finsterlová, Hana ; Diviš, Pavel (referee) ; Dočekalová, Hana (advisor)
This bachelor’s thesis deals with the role of mercury in an environment. It summarizes informations about properties of mercury and its species. The thesis is engaged in the presence of mercury in atmosphere, water, soil and sediments. It deals with individual mercury intakes into the environment, anthropogenic or natural, and it follows transport of mercury between individual components of environment. Part of this thesis is given to the accumulation of mercury and mercury species into plants and organisms. It points out the toxicity of mercury, mercury species, and their effect to human organism. In the last chapter there is a resume and description of the instrumantal methods, which are commonly used for determination mercury and its compounds.
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