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Contaminant transport in karst environment and tracer tests in karst system near Turnov
Malechová, Kateřina ; Slavík, Martin (advisor) ; Weiss, Tomáš (referee)
Karst areas are an important source of drinking water but they are at significant risk of contamination. The theoretical part of the thesis focuses on different types of contaminants, their sources and their ways of transport in karst areas. Due to the high velocity of water flow in karst areas, most contaminants are transported rapidly and spread over long distances. Therefore, it is necessary to actively address the issue of contamination in karst environments, focusing mainly on contamination prevention and water flow studies. In the practical part of the thesis, a quantitative tracer test was carried out in the karst system near Turnov using NaCl as a tracer. The measurements confirmed a high water flow velocity of several kilometers per day and the dominance of advection as the main transport process. These results are consistent with previous research. The connection between the sinking stream Šálení smyslů and the Slapy and Bezednice springs was also reconfirmed, with a total recovery of around 50%. This implies that water from the Šálení smyslů most likely flows to other, yet unknown, locations. No communication with the Bartošova pec cave or with the springs used as a source for the local brewery has been demonstrated, so the question remains where all the water from the sinking stream...
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Research on the load-carrying capacity of lubricating film in rolling bearings
Šmíd, David ; Čermák, Jan (referee) ; Omasta, Milan (advisor)
This diploma thesis deals with the problem of sudden contamination of the elastohydrodynamic contact by solid particles and their influence on parameters affecting the lubricating film, such as surface texture and real film thickness, especially for line contact. The contact is operated under conditions corresponding to the operation of the main wind turbine bearings, with measurable parameters supported by optical observations. The main effort of this work is to relate the influence of the flow of solid particles in the lubricant to the parameters determining the lubrication regime. For the experiments, a taper-on-disc device was constructed to simulate linear contact. Using this device, the effects of different solid particles on the damage of a sample (roughness parameters Ra and Rq) with linear contact and the influence of this altered structure on the lubricating film thickness (hmin) are experimentally described. These remarks are partially compared with the effect of particles on point contact. The result of this paper is a better understanding of the solid particle flow in the Hertzian contact region and clarification of the influence of this flow on the surface structure and associated lubricating film thickness, especially for linear contact.
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New procedures for autonomous analyses of dried blood spots by capillary electrophoresis
Profousová, Sylvie ; Glatz, Zdeněk (referee) ; Dvořák, Miloš (advisor)
Collection of capillary blood in the form of dry blood spot (DBS) samples on cellulose sampling cards has been popular in clinical analysis for some time. However, in the diagnosis and monitoring of metabolic disorders and diseases, target analytes (e.g. inorganic and organic ions) are examined from blood plasma or serum. Determination of the target analytes from capillary blood or DBS samples is not the standard and reference values are not available due to the different composition of plasma/serum vs. capillary blood. Moreover, DBS sorbents have been found to release several ions into DBS eluates resulting in their contamination and, together with the effect of blood hematocrit and retention of target analytes, can adversely affect the quantitative analysis of DBS samples. For these reasons, this thesis addresses the design of an alternative concept for DBS collection that would eliminate the use of sampling sorbents and ensure the collection of a defined and precise volume of blood. The experimental part focuses on the determination of selected inorganic and organic ions (NH4+, K+, Na+, Ca2+, Mg2+, Cl, NO3, NO2, SO42, formate, lactate, and acetate) by capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D) in various DBS samples. All these ions are present in blood at different concentrations and can be simultaneously released as contaminants from the DBS sorbents. A non-porous polypropylene vial was used for the novel sorbentless DBS collection. A small drop of blood of defined volume (e.g. 5 l) was transferred into this vial and then dried directly therein. The selected vial is suitable for both direct DBS elution and DBS eluate analysis and is fully compatible with autosamplers of commercial CE instruments. The proposed concept of the sorbentless blood collection eliminated unwanted contamination and proved suitable for the determination of the tested cations and anions. The stability of anions was generally lower than that of cations but was still significantly better compared to standard DBS sampling sorbents. Determination of some anions appeared to be acceptable only within 0–48 hours after drying of the sorbentless DBS samples (stored at laboratory temperature), as there was a continuous increase in their content. This was probably due to microbial degradation of the blood matrix. It was confirmed that this increase could be slowed down by storing sorbentless DBS samples at low temperatures. Different blood sampling procedures have been proposed for sorbentless DBS collection that are simple, economical, convenient, and repeatable and are therefore suitable for patient-centric blood sampling as well as for sampling in medical centers. This is a basic pilot study applied only to selected analytes that served as model examples, nevertheless, based on this thesis, more extensive scientific studies will follow up to further develop the new concept of sorbentless DBS collection.
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Preservative systems for natural cosmetics
Koblasová, Dana ; Veselá, Mária (referee) ; Zemanová, Jana (advisor)
The aim of this bachelor thesis is to evaluate the antimicrobial activity of naturally derived preservatives against selected microorganisms. Theoretical part is focused on description of the most used natural, naturally derived and synthetic preservatives, on the safety of preservatives and finally, the issue of contamination of cosmetic products by microorganisms. In experimental part, antimicrobial activity of 4 naturally derived preservatives was evaluated against selected microorganisms, which were bacteria Micrococcus luteus, Kocuria rosea, Bacillus cereus, Bacillus subtilis, Serratia marcescens and one yeast Candida vini. The tested preservatives were from MinaSolve company - E-LEEN Green A, which contains pentylene glycol and phenylpropanol, E-LEEN Green OR, which is composed of citrus extracts, citric acid, ascorbic acid and pentylene glycol, Green B, which contains benzoic acid, sodium benzoate and pentylene glycol and Hexam+, which is a mixture of pentylene glycol and hexamidin diisethionate. Antimicrobial activity was evaluated by agar diffusion method. The highest antimicrobial activity showed Hexam+, the lowest E-LEEN Green OR. E-LEEN Green A and Green B did not show any antimicrobial activity against any microorganism in the 1% tested concentration. The measured values of the inhibition zones show that the most resistant microorganisms from all the tested in this thesis are Bacillus cereus and Bacillus subtilis and the least resistant are Micrococcus luteus and Kocuria rosea.
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Hair as a bioindicator of contamination of risk metals
Zmijová, Marie ; Řezáčová, Veronika (referee) ; Zlámalová Gargošová, Helena (advisor)
The use of hair as a bioindicator of environmental contamination by risk elements is becoming more and more common. This bachelor thesis deals with the use of this matrix for analysis using the voltammetric method. It focuses on the optimization of the method for determining the concentration of cadmium, copper, lead and zinc in real hair samples and monitors the effects on the incorporation of these elements into the hair fiber. The presence of zinc and copper was confirmed in all samples analyzed. Cadmium could only be quantified in one sample. The effect of gender and age on the concentration of elements has not been demonstrated. Concentration of lead has been linked to smoking, with higher concentrations found in smoker’s hair than in non-smoker’s.
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Assessmant of surfactants levels in waters
Zajícová, Markéta ; Doležalová Weissmannová, Helena (referee) ; Vávrová, Milada (advisor)
The present Bachelor Thesis deals with problem of water contamination by synthetic surfactants. Surfactants represent the main component of washing and cleaning agents, from which they enter waste waters. The goal of Thesis was to monitor and evaluate volume of surfactants in waste waters from waste water treatment plant VFU Brno. Samples were being taken in the course of 7 days and we have monitored volume of anionic and cationic tensides in samples from influent and effluent stream of waste water treatment plant. For qualitative and quantitative determination were used mobile analytic measurement devices with photometric detection by company Merck. Results were processed and interpreted in data evaluation section in the end of this Bachelor Thesis.
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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.
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Chromium and chromium species cycle in environment
Nevrlá, Jana ; Sommer, Lumír (referee) ; Dočekalová, Hana (advisor)
This work focuses in the first theoretical part mainly on the possibility of entering various forms of chromium into the environment, their accumulation and transformation in environmental compartments. There are also described methods of sampling for analytical determination of chromium, the type of treatment of these samples and the most analytical methodologies for the determination of chromium in the oxidation stage III and VI. The experimental part is focused on the quantitative determination of Cr(III) and Cr(VI) in waste water, taken from the neutralizatoin station of the Chemical faculty of Brno University of Technology, by using selected spectrophotometric methods and the obtained results are compared with the results of analytical determination of total chromium by atomic absorption spectrometry.
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Persistent Organic Pollutants in the Environment of the Southern Moravia Region
Lána, Radim ; Kráčmar, Stanislav (referee) ; Večeřa, Zbyněk (referee) ; Hajšlová, Jana (referee) ; Vávrová, Milada (advisor)
Byla provedena studie bioakumulace POP v potravním řetězci a historických trendů hladin POP v sedimentech Brněnské přehrady. Současné úrovně kontaminantů byly stanoveny v jelci tloušti z řeky Svratky a rovněž byla posouzena hygienická kvalita ryb z rekreačního rybolovu. Současné úrovně POP v terestrickém ekosystému byly posouzeny pomocí analýz jehličí jako přirozeného indikátoru znečištění. Studium jedinců tří druhů dravých ptáků z ČR bylo zaměřeno na zhodnocení kontaminace těchto vrcholných predátorů POP. S pomocí analýz vybraných druhů ryb ze Záhlinických rybníků byl rovněž studován proces bioakumulace. Posouzení parametrů dvou moderních extrakčních technik a jejich využitelnosti pro izolaci POP z různých matric bylo námětem poslední části dizertace.
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Presence of heavy metals in vicinity of the roads in Brno
Brzobohatý, Jan ; Adamec, Vladimír (referee) ; Doležalová Weissmannová, Helena (advisor)
Diploma thesis deals with the risk assessment of metals in soils near roads in the city of Brno. For samples collection has been chosen twenty-five localities which were divided into five groups depending on the traffic load, in order to compare the impact of transport on the risk of soil contamination with metals. In the soil samples were determined levels of six hazardous metals (Cd, Hg, Pb, Zn, Ni, Cu). Lead, zinc, nickel and copper were determined by the flame atomic absorption spectrometry (F-AAS), cadmium by the electrotermic atomic absorption spectrometry (ET-AAS) and mercury by the advanced mercury analyzer AMA 254.
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